Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 1 | /* |
| 2 | This is a version (aka dlmalloc) of malloc/free/realloc written by |
| 3 | Doug Lea and released to the public domain, as explained at |
| 4 | http://creativecommons.org/publicdomain/zero/1.0/ Send questions, |
| 5 | comments, complaints, performance data, etc to dl@cs.oswego.edu |
| 6 | */ |
| 7 | |
| 8 | #include <vppinfra/dlmalloc.h> |
| 9 | |
| 10 | /*------------------------------ internal #includes ---------------------- */ |
| 11 | |
| 12 | #ifdef _MSC_VER |
| 13 | #pragma warning( disable : 4146 ) /* no "unsigned" warnings */ |
| 14 | #endif /* _MSC_VER */ |
| 15 | #if !NO_MALLOC_STATS |
| 16 | #include <stdio.h> /* for printing in malloc_stats */ |
| 17 | #endif /* NO_MALLOC_STATS */ |
| 18 | #ifndef LACKS_ERRNO_H |
| 19 | #include <errno.h> /* for MALLOC_FAILURE_ACTION */ |
| 20 | #endif /* LACKS_ERRNO_H */ |
| 21 | #ifdef DEBUG |
| 22 | #if DLM_ABORT_ON_ASSERT_FAILURE |
| 23 | #undef assert |
| 24 | #define assert(x) if(!(x)) DLM_ABORT |
| 25 | #else /* DLM_ABORT_ON_ASSERT_FAILURE */ |
| 26 | #include <assert.h> |
| 27 | #endif /* DLM_ABORT_ON_ASSERT_FAILURE */ |
| 28 | #else /* DEBUG */ |
| 29 | #ifndef assert |
| 30 | #define assert(x) |
| 31 | #endif |
| 32 | #define DEBUG 0 |
| 33 | #endif /* DEBUG */ |
| 34 | #if !defined(WIN32) && !defined(LACKS_TIME_H) |
| 35 | #include <time.h> /* for magic initialization */ |
| 36 | #endif /* WIN32 */ |
| 37 | #ifndef LACKS_STDLIB_H |
| 38 | #include <stdlib.h> /* for abort() */ |
| 39 | #endif /* LACKS_STDLIB_H */ |
| 40 | #ifndef LACKS_STRING_H |
| 41 | #include <string.h> /* for memset etc */ |
| 42 | #endif /* LACKS_STRING_H */ |
| 43 | #if USE_BUILTIN_FFS |
| 44 | #ifndef LACKS_STRINGS_H |
| 45 | #include <strings.h> /* for ffs */ |
| 46 | #endif /* LACKS_STRINGS_H */ |
| 47 | #endif /* USE_BUILTIN_FFS */ |
| 48 | #if HAVE_MMAP |
| 49 | #ifndef LACKS_SYS_MMAN_H |
| 50 | /* On some versions of linux, mremap decl in mman.h needs __USE_GNU set */ |
| 51 | #if (defined(linux) && !defined(__USE_GNU)) |
| 52 | #define __USE_GNU 1 |
| 53 | #include <sys/mman.h> /* for mmap */ |
| 54 | #undef __USE_GNU |
| 55 | #else |
| 56 | #include <sys/mman.h> /* for mmap */ |
| 57 | #endif /* linux */ |
| 58 | #endif /* LACKS_SYS_MMAN_H */ |
| 59 | #ifndef LACKS_FCNTL_H |
| 60 | #include <fcntl.h> |
| 61 | #endif /* LACKS_FCNTL_H */ |
| 62 | #endif /* HAVE_MMAP */ |
| 63 | #ifndef LACKS_UNISTD_H |
| 64 | #include <unistd.h> /* for sbrk, sysconf */ |
| 65 | #else /* LACKS_UNISTD_H */ |
| 66 | #if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) |
| 67 | extern void* sbrk(ptrdiff_t); |
| 68 | #endif /* FreeBSD etc */ |
| 69 | #endif /* LACKS_UNISTD_H */ |
| 70 | |
| 71 | /* Declarations for locking */ |
| 72 | #if USE_LOCKS |
| 73 | #ifndef WIN32 |
| 74 | #if defined (__SVR4) && defined (__sun) /* solaris */ |
| 75 | #include <thread.h> |
| 76 | #elif !defined(LACKS_SCHED_H) |
| 77 | #include <sched.h> |
| 78 | #endif /* solaris or LACKS_SCHED_H */ |
| 79 | #if (defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0) || !USE_SPIN_LOCKS |
| 80 | #include <pthread.h> |
| 81 | #endif /* USE_RECURSIVE_LOCKS ... */ |
| 82 | #elif defined(_MSC_VER) |
| 83 | #ifndef _M_AMD64 |
| 84 | /* These are already defined on AMD64 builds */ |
| 85 | #ifdef __cplusplus |
| 86 | extern "C" { |
| 87 | #endif /* __cplusplus */ |
| 88 | LONG __cdecl _InterlockedCompareExchange(LONG volatile *Dest, LONG Exchange, LONG Comp); |
| 89 | LONG __cdecl _InterlockedExchange(LONG volatile *Target, LONG Value); |
| 90 | #ifdef __cplusplus |
| 91 | } |
| 92 | #endif /* __cplusplus */ |
| 93 | #endif /* _M_AMD64 */ |
| 94 | #pragma intrinsic (_InterlockedCompareExchange) |
| 95 | #pragma intrinsic (_InterlockedExchange) |
| 96 | #define interlockedcompareexchange _InterlockedCompareExchange |
| 97 | #define interlockedexchange _InterlockedExchange |
| 98 | #elif defined(WIN32) && defined(__GNUC__) |
| 99 | #define interlockedcompareexchange(a, b, c) __sync_val_compare_and_swap(a, c, b) |
| 100 | #define interlockedexchange __sync_lock_test_and_set |
| 101 | #endif /* Win32 */ |
| 102 | #else /* USE_LOCKS */ |
| 103 | #endif /* USE_LOCKS */ |
| 104 | |
| 105 | #ifndef LOCK_AT_FORK |
| 106 | #define LOCK_AT_FORK 0 |
| 107 | #endif |
| 108 | |
| 109 | /* Declarations for bit scanning on win32 */ |
| 110 | #if defined(_MSC_VER) && _MSC_VER>=1300 |
| 111 | #ifndef BitScanForward /* Try to avoid pulling in WinNT.h */ |
| 112 | #ifdef __cplusplus |
| 113 | extern "C" { |
| 114 | #endif /* __cplusplus */ |
| 115 | unsigned char _BitScanForward(unsigned long *index, unsigned long mask); |
| 116 | unsigned char _BitScanReverse(unsigned long *index, unsigned long mask); |
| 117 | #ifdef __cplusplus |
| 118 | } |
| 119 | #endif /* __cplusplus */ |
| 120 | |
| 121 | #define BitScanForward _BitScanForward |
| 122 | #define BitScanReverse _BitScanReverse |
| 123 | #pragma intrinsic(_BitScanForward) |
| 124 | #pragma intrinsic(_BitScanReverse) |
| 125 | #endif /* BitScanForward */ |
| 126 | #endif /* defined(_MSC_VER) && _MSC_VER>=1300 */ |
| 127 | |
| 128 | #ifndef WIN32 |
| 129 | #ifndef malloc_getpagesize |
| 130 | # ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */ |
| 131 | # ifndef _SC_PAGE_SIZE |
| 132 | # define _SC_PAGE_SIZE _SC_PAGESIZE |
| 133 | # endif |
| 134 | # endif |
| 135 | # ifdef _SC_PAGE_SIZE |
| 136 | # define malloc_getpagesize sysconf(_SC_PAGE_SIZE) |
| 137 | # else |
| 138 | # if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE) |
| 139 | extern size_t getpagesize(); |
| 140 | # define malloc_getpagesize getpagesize() |
| 141 | # else |
| 142 | # ifdef WIN32 /* use supplied emulation of getpagesize */ |
| 143 | # define malloc_getpagesize getpagesize() |
| 144 | # else |
| 145 | # ifndef LACKS_SYS_PARAM_H |
| 146 | # include <sys/param.h> |
| 147 | # endif |
| 148 | # ifdef EXEC_PAGESIZE |
| 149 | # define malloc_getpagesize EXEC_PAGESIZE |
| 150 | # else |
| 151 | # ifdef NBPG |
| 152 | # ifndef CLSIZE |
| 153 | # define malloc_getpagesize NBPG |
| 154 | # else |
| 155 | # define malloc_getpagesize (NBPG * CLSIZE) |
| 156 | # endif |
| 157 | # else |
| 158 | # ifdef NBPC |
| 159 | # define malloc_getpagesize NBPC |
| 160 | # else |
| 161 | # ifdef PAGESIZE |
| 162 | # define malloc_getpagesize PAGESIZE |
| 163 | # else /* just guess */ |
| 164 | # define malloc_getpagesize ((size_t)4096U) |
| 165 | # endif |
| 166 | # endif |
| 167 | # endif |
| 168 | # endif |
| 169 | # endif |
| 170 | # endif |
| 171 | # endif |
| 172 | #endif |
| 173 | #endif |
| 174 | |
| 175 | /* ------------------- size_t and alignment properties -------------------- */ |
| 176 | |
| 177 | /* The byte and bit size of a size_t */ |
| 178 | #define SIZE_T_SIZE (sizeof(size_t)) |
| 179 | #define SIZE_T_BITSIZE (sizeof(size_t) << 3) |
| 180 | |
| 181 | /* Some constants coerced to size_t */ |
| 182 | /* Annoying but necessary to avoid errors on some platforms */ |
| 183 | #define SIZE_T_ZERO ((size_t)0) |
| 184 | #define SIZE_T_ONE ((size_t)1) |
| 185 | #define SIZE_T_TWO ((size_t)2) |
| 186 | #define SIZE_T_FOUR ((size_t)4) |
| 187 | #define TWO_SIZE_T_SIZES (SIZE_T_SIZE<<1) |
| 188 | #define FOUR_SIZE_T_SIZES (SIZE_T_SIZE<<2) |
| 189 | #define SIX_SIZE_T_SIZES (FOUR_SIZE_T_SIZES+TWO_SIZE_T_SIZES) |
| 190 | #define HALF_MAX_SIZE_T (MAX_SIZE_T / 2U) |
| 191 | |
| 192 | /* The bit mask value corresponding to MALLOC_ALIGNMENT */ |
| 193 | #define CHUNK_ALIGN_MASK (MALLOC_ALIGNMENT - SIZE_T_ONE) |
| 194 | |
| 195 | /* True if address a has acceptable alignment */ |
| 196 | #define is_aligned(A) (((size_t)((A)) & (CHUNK_ALIGN_MASK)) == 0) |
| 197 | |
| 198 | /* the number of bytes to offset an address to align it */ |
| 199 | #define align_offset(A)\ |
| 200 | ((((size_t)(A) & CHUNK_ALIGN_MASK) == 0)? 0 :\ |
| 201 | ((MALLOC_ALIGNMENT - ((size_t)(A) & CHUNK_ALIGN_MASK)) & CHUNK_ALIGN_MASK)) |
| 202 | |
| 203 | /* -------------------------- MMAP preliminaries ------------------------- */ |
| 204 | |
| 205 | /* |
| 206 | If HAVE_MORECORE or HAVE_MMAP are false, we just define calls and |
| 207 | checks to fail so compiler optimizer can delete code rather than |
| 208 | using so many "#if"s. |
| 209 | */ |
| 210 | |
| 211 | |
| 212 | /* MORECORE and MMAP must return MFAIL on failure */ |
| 213 | #define MFAIL ((void*)(MAX_SIZE_T)) |
| 214 | #define CMFAIL ((char*)(MFAIL)) /* defined for convenience */ |
| 215 | |
| 216 | #if HAVE_MMAP |
| 217 | |
| 218 | #ifndef WIN32 |
| 219 | #define MUNMAP_DEFAULT(a, s) munmap((a), (s)) |
| 220 | #define MMAP_PROT (PROT_READ|PROT_WRITE) |
| 221 | #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON) |
| 222 | #define MAP_ANONYMOUS MAP_ANON |
| 223 | #endif /* MAP_ANON */ |
| 224 | #ifdef MAP_ANONYMOUS |
| 225 | #define MMAP_FLAGS (MAP_PRIVATE|MAP_ANONYMOUS) |
| 226 | #define MMAP_DEFAULT(s) mmap(0, (s), MMAP_PROT, MMAP_FLAGS, -1, 0) |
| 227 | #else /* MAP_ANONYMOUS */ |
| 228 | /* |
| 229 | Nearly all versions of mmap support MAP_ANONYMOUS, so the following |
| 230 | is unlikely to be needed, but is supplied just in case. |
| 231 | */ |
| 232 | #define MMAP_FLAGS (MAP_PRIVATE) |
| 233 | static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */ |
| 234 | #define MMAP_DEFAULT(s) ((dev_zero_fd < 0) ? \ |
| 235 | (dev_zero_fd = open("/dev/zero", O_RDWR), \ |
| 236 | mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \ |
| 237 | mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) |
| 238 | #endif /* MAP_ANONYMOUS */ |
| 239 | |
| 240 | #define DIRECT_MMAP_DEFAULT(s) MMAP_DEFAULT(s) |
| 241 | |
| 242 | #else /* WIN32 */ |
| 243 | |
| 244 | /* Win32 MMAP via VirtualAlloc */ |
| 245 | static FORCEINLINE void* win32mmap(size_t size) { |
| 246 | void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE); |
| 247 | return (ptr != 0)? ptr: MFAIL; |
| 248 | } |
| 249 | |
| 250 | /* For direct MMAP, use MEM_TOP_DOWN to minimize interference */ |
| 251 | static FORCEINLINE void* win32direct_mmap(size_t size) { |
| 252 | void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN, |
| 253 | PAGE_READWRITE); |
| 254 | return (ptr != 0)? ptr: MFAIL; |
| 255 | } |
| 256 | |
| 257 | /* This function supports releasing coalesed segments */ |
| 258 | static FORCEINLINE int win32munmap(void* ptr, size_t size) { |
| 259 | MEMORY_BASIC_INFORMATION minfo; |
| 260 | char* cptr = (char*)ptr; |
| 261 | while (size) { |
| 262 | if (VirtualQuery(cptr, &minfo, sizeof(minfo)) == 0) |
| 263 | return -1; |
| 264 | if (minfo.BaseAddress != cptr || minfo.AllocationBase != cptr || |
| 265 | minfo.State != MEM_COMMIT || minfo.RegionSize > size) |
| 266 | return -1; |
| 267 | if (VirtualFree(cptr, 0, MEM_RELEASE) == 0) |
| 268 | return -1; |
| 269 | cptr += minfo.RegionSize; |
| 270 | size -= minfo.RegionSize; |
| 271 | } |
| 272 | return 0; |
| 273 | } |
| 274 | |
| 275 | #define MMAP_DEFAULT(s) win32mmap(s) |
| 276 | #define MUNMAP_DEFAULT(a, s) win32munmap((a), (s)) |
| 277 | #define DIRECT_MMAP_DEFAULT(s) win32direct_mmap(s) |
| 278 | #endif /* WIN32 */ |
| 279 | #endif /* HAVE_MMAP */ |
| 280 | |
| 281 | #if HAVE_MREMAP |
| 282 | #ifndef WIN32 |
| 283 | #define MREMAP_DEFAULT(addr, osz, nsz, mv) mremap((addr), (osz), (nsz), (mv)) |
| 284 | #endif /* WIN32 */ |
| 285 | #endif /* HAVE_MREMAP */ |
| 286 | |
| 287 | /** |
| 288 | * Define CALL_MORECORE |
| 289 | */ |
| 290 | #if HAVE_MORECORE |
| 291 | #ifdef MORECORE |
| 292 | #define CALL_MORECORE(S) MORECORE(S) |
| 293 | #else /* MORECORE */ |
| 294 | #define CALL_MORECORE(S) MORECORE_DEFAULT(S) |
| 295 | #endif /* MORECORE */ |
| 296 | #else /* HAVE_MORECORE */ |
| 297 | #define CALL_MORECORE(S) MFAIL |
| 298 | #endif /* HAVE_MORECORE */ |
| 299 | |
| 300 | /** |
| 301 | * Define CALL_MMAP/CALL_MUNMAP/CALL_DIRECT_MMAP |
| 302 | */ |
| 303 | #if HAVE_MMAP |
| 304 | #define USE_MMAP_BIT (SIZE_T_ONE) |
| 305 | |
| 306 | #ifdef MMAP |
| 307 | #define CALL_MMAP(s) MMAP(s) |
| 308 | #else /* MMAP */ |
| 309 | #define CALL_MMAP(s) MMAP_DEFAULT(s) |
| 310 | #endif /* MMAP */ |
| 311 | #ifdef MUNMAP |
| 312 | #define CALL_MUNMAP(a, s) MUNMAP((a), (s)) |
| 313 | #else /* MUNMAP */ |
| 314 | #define CALL_MUNMAP(a, s) MUNMAP_DEFAULT((a), (s)) |
| 315 | #endif /* MUNMAP */ |
| 316 | #ifdef DIRECT_MMAP |
| 317 | #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s) |
| 318 | #else /* DIRECT_MMAP */ |
| 319 | #define CALL_DIRECT_MMAP(s) DIRECT_MMAP_DEFAULT(s) |
| 320 | #endif /* DIRECT_MMAP */ |
| 321 | #else /* HAVE_MMAP */ |
| 322 | #define USE_MMAP_BIT (SIZE_T_ZERO) |
| 323 | |
| 324 | #define MMAP(s) MFAIL |
| 325 | #define MUNMAP(a, s) (-1) |
| 326 | #define DIRECT_MMAP(s) MFAIL |
| 327 | #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s) |
| 328 | #define CALL_MMAP(s) MMAP(s) |
| 329 | #define CALL_MUNMAP(a, s) MUNMAP((a), (s)) |
| 330 | #endif /* HAVE_MMAP */ |
| 331 | |
| 332 | /** |
| 333 | * Define CALL_MREMAP |
| 334 | */ |
| 335 | #if HAVE_MMAP && HAVE_MREMAP |
| 336 | #ifdef MREMAP |
| 337 | #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP((addr), (osz), (nsz), (mv)) |
| 338 | #else /* MREMAP */ |
| 339 | #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP_DEFAULT((addr), (osz), (nsz), (mv)) |
| 340 | #endif /* MREMAP */ |
| 341 | #else /* HAVE_MMAP && HAVE_MREMAP */ |
| 342 | #define CALL_MREMAP(addr, osz, nsz, mv) MFAIL |
| 343 | #endif /* HAVE_MMAP && HAVE_MREMAP */ |
| 344 | |
Paul Vinciguerra | ec11b13 | 2018-09-24 05:25:00 -0700 | [diff] [blame] | 345 | /* mstate bit set if contiguous morecore disabled or failed */ |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 346 | #define USE_NONCONTIGUOUS_BIT (4U) |
| 347 | |
| 348 | /* mstate bit set if no expansion allowed */ |
| 349 | #define USE_NOEXPAND_BIT (8U) |
| 350 | |
| 351 | /* trace allocations if set */ |
| 352 | #define USE_TRACE_BIT (16U) |
| 353 | |
| 354 | /* segment bit set in create_mspace_with_base */ |
| 355 | #define EXTERN_BIT (8U) |
| 356 | |
| 357 | |
| 358 | /* --------------------------- Lock preliminaries ------------------------ */ |
| 359 | |
| 360 | /* |
| 361 | When locks are defined, there is one global lock, plus |
| 362 | one per-mspace lock. |
| 363 | |
| 364 | The global lock_ensures that mparams.magic and other unique |
| 365 | mparams values are initialized only once. It also protects |
| 366 | sequences of calls to MORECORE. In many cases sys_alloc requires |
| 367 | two calls, that should not be interleaved with calls by other |
| 368 | threads. This does not protect against direct calls to MORECORE |
| 369 | by other threads not using this lock, so there is still code to |
| 370 | cope the best we can on interference. |
| 371 | |
| 372 | Per-mspace locks surround calls to malloc, free, etc. |
| 373 | By default, locks are simple non-reentrant mutexes. |
| 374 | |
| 375 | Because lock-protected regions generally have bounded times, it is |
| 376 | OK to use the supplied simple spinlocks. Spinlocks are likely to |
| 377 | improve performance for lightly contended applications, but worsen |
| 378 | performance under heavy contention. |
| 379 | |
| 380 | If USE_LOCKS is > 1, the definitions of lock routines here are |
| 381 | bypassed, in which case you will need to define the type MLOCK_T, |
| 382 | and at least INITIAL_LOCK, DESTROY_LOCK, ACQUIRE_LOCK, RELEASE_LOCK |
| 383 | and TRY_LOCK. You must also declare a |
| 384 | static MLOCK_T malloc_global_mutex = { initialization values };. |
| 385 | |
| 386 | */ |
| 387 | |
| 388 | #if !USE_LOCKS |
| 389 | #define USE_LOCK_BIT (0U) |
| 390 | #define INITIAL_LOCK(l) (0) |
| 391 | #define DESTROY_LOCK(l) (0) |
| 392 | #define ACQUIRE_MALLOC_GLOBAL_LOCK() |
| 393 | #define RELEASE_MALLOC_GLOBAL_LOCK() |
| 394 | |
| 395 | #else |
| 396 | #if USE_LOCKS > 1 |
| 397 | /* ----------------------- User-defined locks ------------------------ */ |
| 398 | /* Define your own lock implementation here */ |
| 399 | /* #define INITIAL_LOCK(lk) ... */ |
| 400 | /* #define DESTROY_LOCK(lk) ... */ |
| 401 | /* #define ACQUIRE_LOCK(lk) ... */ |
| 402 | /* #define RELEASE_LOCK(lk) ... */ |
| 403 | /* #define TRY_LOCK(lk) ... */ |
| 404 | /* static MLOCK_T malloc_global_mutex = ... */ |
| 405 | |
| 406 | #elif USE_SPIN_LOCKS |
| 407 | |
| 408 | /* First, define CAS_LOCK and CLEAR_LOCK on ints */ |
| 409 | /* Note CAS_LOCK defined to return 0 on success */ |
| 410 | |
| 411 | #if defined(__GNUC__)&& (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)) |
| 412 | #define CAS_LOCK(sl) __sync_lock_test_and_set(sl, 1) |
| 413 | #define CLEAR_LOCK(sl) __sync_lock_release(sl) |
| 414 | |
| 415 | #elif (defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))) |
| 416 | /* Custom spin locks for older gcc on x86 */ |
| 417 | static FORCEINLINE int x86_cas_lock(int *sl) { |
| 418 | int ret; |
| 419 | int val = 1; |
| 420 | int cmp = 0; |
| 421 | __asm__ __volatile__ ("lock; cmpxchgl %1, %2" |
| 422 | : "=a" (ret) |
| 423 | : "r" (val), "m" (*(sl)), "0"(cmp) |
| 424 | : "memory", "cc"); |
| 425 | return ret; |
| 426 | } |
| 427 | |
| 428 | static FORCEINLINE void x86_clear_lock(int* sl) { |
| 429 | assert(*sl != 0); |
| 430 | int prev = 0; |
| 431 | int ret; |
| 432 | __asm__ __volatile__ ("lock; xchgl %0, %1" |
| 433 | : "=r" (ret) |
| 434 | : "m" (*(sl)), "0"(prev) |
| 435 | : "memory"); |
| 436 | } |
| 437 | |
| 438 | #define CAS_LOCK(sl) x86_cas_lock(sl) |
| 439 | #define CLEAR_LOCK(sl) x86_clear_lock(sl) |
| 440 | |
| 441 | #else /* Win32 MSC */ |
| 442 | #define CAS_LOCK(sl) interlockedexchange(sl, (LONG)1) |
| 443 | #define CLEAR_LOCK(sl) interlockedexchange (sl, (LONG)0) |
| 444 | |
| 445 | #endif /* ... gcc spins locks ... */ |
| 446 | |
| 447 | /* How to yield for a spin lock */ |
| 448 | #define SPINS_PER_YIELD 63 |
| 449 | #if defined(_MSC_VER) |
| 450 | #define SLEEP_EX_DURATION 50 /* delay for yield/sleep */ |
| 451 | #define SPIN_LOCK_YIELD SleepEx(SLEEP_EX_DURATION, FALSE) |
| 452 | #elif defined (__SVR4) && defined (__sun) /* solaris */ |
| 453 | #define SPIN_LOCK_YIELD thr_yield(); |
| 454 | #elif !defined(LACKS_SCHED_H) |
| 455 | #define SPIN_LOCK_YIELD sched_yield(); |
| 456 | #else |
| 457 | #define SPIN_LOCK_YIELD |
| 458 | #endif /* ... yield ... */ |
| 459 | |
| 460 | #if !defined(USE_RECURSIVE_LOCKS) || USE_RECURSIVE_LOCKS == 0 |
| 461 | /* Plain spin locks use single word (embedded in malloc_states) */ |
| 462 | static int spin_acquire_lock(int *sl) { |
| 463 | int spins = 0; |
| 464 | while (*(volatile int *)sl != 0 || CAS_LOCK(sl)) { |
| 465 | if ((++spins & SPINS_PER_YIELD) == 0) { |
| 466 | SPIN_LOCK_YIELD; |
| 467 | } |
| 468 | } |
| 469 | return 0; |
| 470 | } |
| 471 | |
| 472 | #define MLOCK_T int |
| 473 | #define TRY_LOCK(sl) !CAS_LOCK(sl) |
| 474 | #define RELEASE_LOCK(sl) CLEAR_LOCK(sl) |
| 475 | #define ACQUIRE_LOCK(sl) (CAS_LOCK(sl)? spin_acquire_lock(sl) : 0) |
| 476 | #define INITIAL_LOCK(sl) (*sl = 0) |
| 477 | #define DESTROY_LOCK(sl) (0) |
| 478 | static MLOCK_T malloc_global_mutex = 0; |
| 479 | |
| 480 | #else /* USE_RECURSIVE_LOCKS */ |
| 481 | /* types for lock owners */ |
| 482 | #ifdef WIN32 |
| 483 | #define THREAD_ID_T DWORD |
| 484 | #define CURRENT_THREAD GetCurrentThreadId() |
| 485 | #define EQ_OWNER(X,Y) ((X) == (Y)) |
| 486 | #else |
| 487 | /* |
| 488 | Note: the following assume that pthread_t is a type that can be |
| 489 | initialized to (casted) zero. If this is not the case, you will need to |
| 490 | somehow redefine these or not use spin locks. |
| 491 | */ |
| 492 | #define THREAD_ID_T pthread_t |
| 493 | #define CURRENT_THREAD pthread_self() |
| 494 | #define EQ_OWNER(X,Y) pthread_equal(X, Y) |
| 495 | #endif |
| 496 | |
| 497 | struct malloc_recursive_lock { |
| 498 | int sl; |
| 499 | unsigned int c; |
| 500 | THREAD_ID_T threadid; |
| 501 | }; |
| 502 | |
| 503 | #define MLOCK_T struct malloc_recursive_lock |
| 504 | static MLOCK_T malloc_global_mutex = { 0, 0, (THREAD_ID_T)0}; |
| 505 | |
| 506 | static FORCEINLINE void recursive_release_lock(MLOCK_T *lk) { |
| 507 | assert(lk->sl != 0); |
| 508 | if (--lk->c == 0) { |
| 509 | CLEAR_LOCK(&lk->sl); |
| 510 | } |
| 511 | } |
| 512 | |
| 513 | static FORCEINLINE int recursive_acquire_lock(MLOCK_T *lk) { |
| 514 | THREAD_ID_T mythreadid = CURRENT_THREAD; |
| 515 | int spins = 0; |
| 516 | for (;;) { |
| 517 | if (*((volatile int *)(&lk->sl)) == 0) { |
| 518 | if (!CAS_LOCK(&lk->sl)) { |
| 519 | lk->threadid = mythreadid; |
| 520 | lk->c = 1; |
| 521 | return 0; |
| 522 | } |
| 523 | } |
| 524 | else if (EQ_OWNER(lk->threadid, mythreadid)) { |
| 525 | ++lk->c; |
| 526 | return 0; |
| 527 | } |
| 528 | if ((++spins & SPINS_PER_YIELD) == 0) { |
| 529 | SPIN_LOCK_YIELD; |
| 530 | } |
| 531 | } |
| 532 | } |
| 533 | |
| 534 | static FORCEINLINE int recursive_try_lock(MLOCK_T *lk) { |
| 535 | THREAD_ID_T mythreadid = CURRENT_THREAD; |
| 536 | if (*((volatile int *)(&lk->sl)) == 0) { |
| 537 | if (!CAS_LOCK(&lk->sl)) { |
| 538 | lk->threadid = mythreadid; |
| 539 | lk->c = 1; |
| 540 | return 1; |
| 541 | } |
| 542 | } |
| 543 | else if (EQ_OWNER(lk->threadid, mythreadid)) { |
| 544 | ++lk->c; |
| 545 | return 1; |
| 546 | } |
| 547 | return 0; |
| 548 | } |
| 549 | |
| 550 | #define RELEASE_LOCK(lk) recursive_release_lock(lk) |
| 551 | #define TRY_LOCK(lk) recursive_try_lock(lk) |
| 552 | #define ACQUIRE_LOCK(lk) recursive_acquire_lock(lk) |
| 553 | #define INITIAL_LOCK(lk) ((lk)->threadid = (THREAD_ID_T)0, (lk)->sl = 0, (lk)->c = 0) |
| 554 | #define DESTROY_LOCK(lk) (0) |
| 555 | #endif /* USE_RECURSIVE_LOCKS */ |
| 556 | |
| 557 | #elif defined(WIN32) /* Win32 critical sections */ |
| 558 | #define MLOCK_T CRITICAL_SECTION |
| 559 | #define ACQUIRE_LOCK(lk) (EnterCriticalSection(lk), 0) |
| 560 | #define RELEASE_LOCK(lk) LeaveCriticalSection(lk) |
| 561 | #define TRY_LOCK(lk) TryEnterCriticalSection(lk) |
| 562 | #define INITIAL_LOCK(lk) (!InitializeCriticalSectionAndSpinCount((lk), 0x80000000|4000)) |
| 563 | #define DESTROY_LOCK(lk) (DeleteCriticalSection(lk), 0) |
| 564 | #define NEED_GLOBAL_LOCK_INIT |
| 565 | |
| 566 | static MLOCK_T malloc_global_mutex; |
| 567 | static volatile LONG malloc_global_mutex_status; |
| 568 | |
| 569 | /* Use spin loop to initialize global lock */ |
| 570 | static void init_malloc_global_mutex() { |
| 571 | for (;;) { |
| 572 | long stat = malloc_global_mutex_status; |
| 573 | if (stat > 0) |
| 574 | return; |
| 575 | /* transition to < 0 while initializing, then to > 0) */ |
| 576 | if (stat == 0 && |
| 577 | interlockedcompareexchange(&malloc_global_mutex_status, (LONG)-1, (LONG)0) == 0) { |
| 578 | InitializeCriticalSection(&malloc_global_mutex); |
| 579 | interlockedexchange(&malloc_global_mutex_status, (LONG)1); |
| 580 | return; |
| 581 | } |
| 582 | SleepEx(0, FALSE); |
| 583 | } |
| 584 | } |
| 585 | |
| 586 | #else /* pthreads-based locks */ |
| 587 | #define MLOCK_T pthread_mutex_t |
| 588 | #define ACQUIRE_LOCK(lk) pthread_mutex_lock(lk) |
| 589 | #define RELEASE_LOCK(lk) pthread_mutex_unlock(lk) |
| 590 | #define TRY_LOCK(lk) (!pthread_mutex_trylock(lk)) |
| 591 | #define INITIAL_LOCK(lk) pthread_init_lock(lk) |
| 592 | #define DESTROY_LOCK(lk) pthread_mutex_destroy(lk) |
| 593 | |
| 594 | #if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0 && defined(linux) && !defined(PTHREAD_MUTEX_RECURSIVE) |
| 595 | /* Cope with old-style linux recursive lock initialization by adding */ |
| 596 | /* skipped internal declaration from pthread.h */ |
| 597 | extern int pthread_mutexattr_setkind_np __P ((pthread_mutexattr_t *__attr, |
| 598 | int __kind)); |
| 599 | #define PTHREAD_MUTEX_RECURSIVE PTHREAD_MUTEX_RECURSIVE_NP |
| 600 | #define pthread_mutexattr_settype(x,y) pthread_mutexattr_setkind_np(x,y) |
| 601 | #endif /* USE_RECURSIVE_LOCKS ... */ |
| 602 | |
| 603 | static MLOCK_T malloc_global_mutex = PTHREAD_MUTEX_INITIALIZER; |
| 604 | |
| 605 | static int pthread_init_lock (MLOCK_T *lk) { |
| 606 | pthread_mutexattr_t attr; |
| 607 | if (pthread_mutexattr_init(&attr)) return 1; |
| 608 | #if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0 |
| 609 | if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) return 1; |
| 610 | #endif |
| 611 | if (pthread_mutex_init(lk, &attr)) return 1; |
| 612 | if (pthread_mutexattr_destroy(&attr)) return 1; |
| 613 | return 0; |
| 614 | } |
| 615 | |
| 616 | #endif /* ... lock types ... */ |
| 617 | |
| 618 | /* Common code for all lock types */ |
| 619 | #define USE_LOCK_BIT (2U) |
| 620 | |
| 621 | #ifndef ACQUIRE_MALLOC_GLOBAL_LOCK |
| 622 | #define ACQUIRE_MALLOC_GLOBAL_LOCK() ACQUIRE_LOCK(&malloc_global_mutex); |
| 623 | #endif |
| 624 | |
| 625 | #ifndef RELEASE_MALLOC_GLOBAL_LOCK |
| 626 | #define RELEASE_MALLOC_GLOBAL_LOCK() RELEASE_LOCK(&malloc_global_mutex); |
| 627 | #endif |
| 628 | |
| 629 | #endif /* USE_LOCKS */ |
| 630 | |
| 631 | /* ----------------------- Chunk representations ------------------------ */ |
| 632 | |
| 633 | /* |
| 634 | (The following includes lightly edited explanations by Colin Plumb.) |
| 635 | |
| 636 | The malloc_chunk declaration below is misleading (but accurate and |
| 637 | necessary). It declares a "view" into memory allowing access to |
| 638 | necessary fields at known offsets from a given base. |
| 639 | |
| 640 | Chunks of memory are maintained using a `boundary tag' method as |
| 641 | originally described by Knuth. (See the paper by Paul Wilson |
| 642 | ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a survey of such |
| 643 | techniques.) Sizes of free chunks are stored both in the front of |
| 644 | each chunk and at the end. This makes consolidating fragmented |
| 645 | chunks into bigger chunks fast. The head fields also hold bits |
| 646 | representing whether chunks are free or in use. |
| 647 | |
| 648 | Here are some pictures to make it clearer. They are "exploded" to |
| 649 | show that the state of a chunk can be thought of as extending from |
| 650 | the high 31 bits of the head field of its header through the |
| 651 | prev_foot and PINUSE_BIT bit of the following chunk header. |
| 652 | |
| 653 | A chunk that's in use looks like: |
| 654 | |
| 655 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 656 | | Size of previous chunk (if P = 0) | |
| 657 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 658 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P| |
| 659 | | Size of this chunk 1| +-+ |
| 660 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 661 | | | |
| 662 | +- -+ |
| 663 | | | |
| 664 | +- -+ |
| 665 | | : |
| 666 | +- size - sizeof(size_t) available payload bytes -+ |
| 667 | : | |
| 668 | chunk-> +- -+ |
| 669 | | | |
| 670 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 671 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1| |
| 672 | | Size of next chunk (may or may not be in use) | +-+ |
| 673 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 674 | |
| 675 | And if it's free, it looks like this: |
| 676 | |
| 677 | chunk-> +- -+ |
| 678 | | User payload (must be in use, or we would have merged!) | |
| 679 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 680 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P| |
| 681 | | Size of this chunk 0| +-+ |
| 682 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 683 | | Next pointer | |
| 684 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 685 | | Prev pointer | |
| 686 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 687 | | : |
| 688 | +- size - sizeof(struct chunk) unused bytes -+ |
| 689 | : | |
| 690 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 691 | | Size of this chunk | |
| 692 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 693 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0| |
| 694 | | Size of next chunk (must be in use, or we would have merged)| +-+ |
| 695 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 696 | | : |
| 697 | +- User payload -+ |
| 698 | : | |
| 699 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 700 | |0| |
| 701 | +-+ |
| 702 | Note that since we always merge adjacent free chunks, the chunks |
| 703 | adjacent to a free chunk must be in use. |
| 704 | |
| 705 | Given a pointer to a chunk (which can be derived trivially from the |
| 706 | payload pointer) we can, in O(1) time, find out whether the adjacent |
| 707 | chunks are free, and if so, unlink them from the lists that they |
| 708 | are on and merge them with the current chunk. |
| 709 | |
| 710 | Chunks always begin on even word boundaries, so the mem portion |
| 711 | (which is returned to the user) is also on an even word boundary, and |
| 712 | thus at least double-word aligned. |
| 713 | |
| 714 | The P (PINUSE_BIT) bit, stored in the unused low-order bit of the |
| 715 | chunk size (which is always a multiple of two words), is an in-use |
| 716 | bit for the *previous* chunk. If that bit is *clear*, then the |
| 717 | word before the current chunk size contains the previous chunk |
| 718 | size, and can be used to find the front of the previous chunk. |
| 719 | The very first chunk allocated always has this bit set, preventing |
| 720 | access to non-existent (or non-owned) memory. If pinuse is set for |
| 721 | any given chunk, then you CANNOT determine the size of the |
| 722 | previous chunk, and might even get a memory addressing fault when |
| 723 | trying to do so. |
| 724 | |
| 725 | The C (CINUSE_BIT) bit, stored in the unused second-lowest bit of |
| 726 | the chunk size redundantly records whether the current chunk is |
| 727 | inuse (unless the chunk is mmapped). This redundancy enables usage |
| 728 | checks within free and realloc, and reduces indirection when freeing |
| 729 | and consolidating chunks. |
| 730 | |
| 731 | Each freshly allocated chunk must have both cinuse and pinuse set. |
| 732 | That is, each allocated chunk borders either a previously allocated |
| 733 | and still in-use chunk, or the base of its memory arena. This is |
| 734 | ensured by making all allocations from the `lowest' part of any |
| 735 | found chunk. Further, no free chunk physically borders another one, |
| 736 | so each free chunk is known to be preceded and followed by either |
| 737 | inuse chunks or the ends of memory. |
| 738 | |
| 739 | Note that the `foot' of the current chunk is actually represented |
| 740 | as the prev_foot of the NEXT chunk. This makes it easier to |
| 741 | deal with alignments etc but can be very confusing when trying |
| 742 | to extend or adapt this code. |
| 743 | |
| 744 | The exceptions to all this are |
| 745 | |
| 746 | 1. The special chunk `top' is the top-most available chunk (i.e., |
| 747 | the one bordering the end of available memory). It is treated |
| 748 | specially. Top is never included in any bin, is used only if |
| 749 | no other chunk is available, and is released back to the |
| 750 | system if it is very large (see M_TRIM_THRESHOLD). In effect, |
| 751 | the top chunk is treated as larger (and thus less well |
| 752 | fitting) than any other available chunk. The top chunk |
| 753 | doesn't update its trailing size field since there is no next |
| 754 | contiguous chunk that would have to index off it. However, |
| 755 | space is still allocated for it (TOP_FOOT_SIZE) to enable |
| 756 | separation or merging when space is extended. |
| 757 | |
| 758 | 3. Chunks allocated via mmap, have both cinuse and pinuse bits |
| 759 | cleared in their head fields. Because they are allocated |
| 760 | one-by-one, each must carry its own prev_foot field, which is |
| 761 | also used to hold the offset this chunk has within its mmapped |
| 762 | region, which is needed to preserve alignment. Each mmapped |
| 763 | chunk is trailed by the first two fields of a fake next-chunk |
| 764 | for sake of usage checks. |
| 765 | |
| 766 | */ |
| 767 | |
| 768 | struct malloc_chunk { |
| 769 | size_t prev_foot; /* Size of previous chunk (if free). */ |
| 770 | size_t head; /* Size and inuse bits. */ |
| 771 | struct malloc_chunk* fd; /* double links -- used only if free. */ |
| 772 | struct malloc_chunk* bk; |
| 773 | }; |
| 774 | |
| 775 | typedef struct malloc_chunk mchunk; |
| 776 | typedef struct malloc_chunk* mchunkptr; |
| 777 | typedef struct malloc_chunk* sbinptr; /* The type of bins of chunks */ |
| 778 | typedef unsigned int bindex_t; /* Described below */ |
| 779 | typedef unsigned int binmap_t; /* Described below */ |
| 780 | typedef unsigned int flag_t; /* The type of various bit flag sets */ |
| 781 | |
| 782 | /* ------------------- Chunks sizes and alignments ----------------------- */ |
| 783 | |
| 784 | #define MCHUNK_SIZE (sizeof(mchunk)) |
| 785 | |
| 786 | #if FOOTERS |
| 787 | #define CHUNK_OVERHEAD (TWO_SIZE_T_SIZES) |
| 788 | #else /* FOOTERS */ |
| 789 | #define CHUNK_OVERHEAD (SIZE_T_SIZE) |
| 790 | #endif /* FOOTERS */ |
| 791 | |
| 792 | /* MMapped chunks need a second word of overhead ... */ |
| 793 | #define MMAP_CHUNK_OVERHEAD (TWO_SIZE_T_SIZES) |
| 794 | /* ... and additional padding for fake next-chunk at foot */ |
| 795 | #define MMAP_FOOT_PAD (FOUR_SIZE_T_SIZES) |
| 796 | |
| 797 | /* The smallest size we can malloc is an aligned minimal chunk */ |
| 798 | #define MIN_CHUNK_SIZE\ |
| 799 | ((MCHUNK_SIZE + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK) |
| 800 | |
| 801 | /* conversion from malloc headers to user pointers, and back */ |
| 802 | #define chunk2mem(p) ((void*)((char*)(p) + TWO_SIZE_T_SIZES)) |
| 803 | #define mem2chunk(mem) ((mchunkptr)((char*)(mem) - TWO_SIZE_T_SIZES)) |
| 804 | /* chunk associated with aligned address A */ |
| 805 | #define align_as_chunk(A) (mchunkptr)((A) + align_offset(chunk2mem(A))) |
| 806 | |
| 807 | /* Bounds on request (not chunk) sizes. */ |
| 808 | #define MAX_REQUEST ((-MIN_CHUNK_SIZE) << 2) |
| 809 | #define MIN_REQUEST (MIN_CHUNK_SIZE - CHUNK_OVERHEAD - SIZE_T_ONE) |
| 810 | |
| 811 | /* pad request bytes into a usable size */ |
| 812 | #define pad_request(req) \ |
| 813 | (((req) + CHUNK_OVERHEAD + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK) |
| 814 | |
| 815 | /* pad request, checking for minimum (but not maximum) */ |
| 816 | #define request2size(req) \ |
| 817 | (((req) < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(req)) |
| 818 | |
| 819 | |
| 820 | /* ------------------ Operations on head and foot fields ----------------- */ |
| 821 | |
| 822 | /* |
| 823 | The head field of a chunk is or'ed with PINUSE_BIT when previous |
| 824 | adjacent chunk in use, and or'ed with CINUSE_BIT if this chunk is in |
| 825 | use, unless mmapped, in which case both bits are cleared. |
| 826 | |
| 827 | FLAG4_BIT is not used by this malloc, but might be useful in extensions. |
| 828 | */ |
| 829 | |
| 830 | #define PINUSE_BIT (SIZE_T_ONE) |
| 831 | #define CINUSE_BIT (SIZE_T_TWO) |
| 832 | #define FLAG4_BIT (SIZE_T_FOUR) |
| 833 | #define INUSE_BITS (PINUSE_BIT|CINUSE_BIT) |
| 834 | #define FLAG_BITS (PINUSE_BIT|CINUSE_BIT|FLAG4_BIT) |
| 835 | |
| 836 | /* Head value for fenceposts */ |
| 837 | #define FENCEPOST_HEAD (INUSE_BITS|SIZE_T_SIZE) |
| 838 | |
| 839 | /* extraction of fields from head words */ |
| 840 | #define cinuse(p) ((p)->head & CINUSE_BIT) |
| 841 | #define pinuse(p) ((p)->head & PINUSE_BIT) |
| 842 | #define flag4inuse(p) ((p)->head & FLAG4_BIT) |
| 843 | #define is_inuse(p) (((p)->head & INUSE_BITS) != PINUSE_BIT) |
| 844 | #define is_mmapped(p) (((p)->head & INUSE_BITS) == 0) |
| 845 | |
| 846 | #define chunksize(p) ((p)->head & ~(FLAG_BITS)) |
| 847 | |
| 848 | #define clear_pinuse(p) ((p)->head &= ~PINUSE_BIT) |
| 849 | #define set_flag4(p) ((p)->head |= FLAG4_BIT) |
| 850 | #define clear_flag4(p) ((p)->head &= ~FLAG4_BIT) |
| 851 | |
| 852 | /* Treat space at ptr +/- offset as a chunk */ |
| 853 | #define chunk_plus_offset(p, s) ((mchunkptr)(((char*)(p)) + (s))) |
| 854 | #define chunk_minus_offset(p, s) ((mchunkptr)(((char*)(p)) - (s))) |
| 855 | |
| 856 | /* Ptr to next or previous physical malloc_chunk. */ |
| 857 | #define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->head & ~FLAG_BITS))) |
| 858 | #define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_foot) )) |
| 859 | |
| 860 | /* extract next chunk's pinuse bit */ |
| 861 | #define next_pinuse(p) ((next_chunk(p)->head) & PINUSE_BIT) |
| 862 | |
| 863 | /* Get/set size at footer */ |
| 864 | #define get_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot) |
| 865 | #define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot = (s)) |
| 866 | |
| 867 | /* Set size, pinuse bit, and foot */ |
| 868 | #define set_size_and_pinuse_of_free_chunk(p, s)\ |
| 869 | ((p)->head = (s|PINUSE_BIT), set_foot(p, s)) |
| 870 | |
| 871 | /* Set size, pinuse bit, foot, and clear next pinuse */ |
| 872 | #define set_free_with_pinuse(p, s, n)\ |
| 873 | (clear_pinuse(n), set_size_and_pinuse_of_free_chunk(p, s)) |
| 874 | |
| 875 | /* Get the internal overhead associated with chunk p */ |
| 876 | #define overhead_for(p)\ |
| 877 | (is_mmapped(p)? MMAP_CHUNK_OVERHEAD : CHUNK_OVERHEAD) |
| 878 | |
| 879 | /* Return true if malloced space is not necessarily cleared */ |
| 880 | #if MMAP_CLEARS |
| 881 | #define calloc_must_clear(p) (!is_mmapped(p)) |
| 882 | #else /* MMAP_CLEARS */ |
| 883 | #define calloc_must_clear(p) (1) |
| 884 | #endif /* MMAP_CLEARS */ |
| 885 | |
| 886 | /* ---------------------- Overlaid data structures ----------------------- */ |
| 887 | |
| 888 | /* |
| 889 | When chunks are not in use, they are treated as nodes of either |
| 890 | lists or trees. |
| 891 | |
| 892 | "Small" chunks are stored in circular doubly-linked lists, and look |
| 893 | like this: |
| 894 | |
| 895 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 896 | | Size of previous chunk | |
| 897 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 898 | `head:' | Size of chunk, in bytes |P| |
| 899 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 900 | | Forward pointer to next chunk in list | |
| 901 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 902 | | Back pointer to previous chunk in list | |
| 903 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 904 | | Unused space (may be 0 bytes long) . |
| 905 | . . |
| 906 | . | |
| 907 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 908 | `foot:' | Size of chunk, in bytes | |
| 909 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 910 | |
| 911 | Larger chunks are kept in a form of bitwise digital trees (aka |
| 912 | tries) keyed on chunksizes. Because malloc_tree_chunks are only for |
| 913 | free chunks greater than 256 bytes, their size doesn't impose any |
| 914 | constraints on user chunk sizes. Each node looks like: |
| 915 | |
| 916 | chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 917 | | Size of previous chunk | |
| 918 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 919 | `head:' | Size of chunk, in bytes |P| |
| 920 | mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 921 | | Forward pointer to next chunk of same size | |
| 922 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 923 | | Back pointer to previous chunk of same size | |
| 924 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 925 | | Pointer to left child (child[0]) | |
| 926 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 927 | | Pointer to right child (child[1]) | |
| 928 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 929 | | Pointer to parent | |
| 930 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 931 | | bin index of this chunk | |
| 932 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 933 | | Unused space . |
| 934 | . | |
| 935 | nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 936 | `foot:' | Size of chunk, in bytes | |
| 937 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 938 | |
| 939 | Each tree holding treenodes is a tree of unique chunk sizes. Chunks |
| 940 | of the same size are arranged in a circularly-linked list, with only |
| 941 | the oldest chunk (the next to be used, in our FIFO ordering) |
| 942 | actually in the tree. (Tree members are distinguished by a non-null |
| 943 | parent pointer.) If a chunk with the same size an an existing node |
| 944 | is inserted, it is linked off the existing node using pointers that |
| 945 | work in the same way as fd/bk pointers of small chunks. |
| 946 | |
| 947 | Each tree contains a power of 2 sized range of chunk sizes (the |
| 948 | smallest is 0x100 <= x < 0x180), which is is divided in half at each |
| 949 | tree level, with the chunks in the smaller half of the range (0x100 |
| 950 | <= x < 0x140 for the top nose) in the left subtree and the larger |
| 951 | half (0x140 <= x < 0x180) in the right subtree. This is, of course, |
| 952 | done by inspecting individual bits. |
| 953 | |
| 954 | Using these rules, each node's left subtree contains all smaller |
| 955 | sizes than its right subtree. However, the node at the root of each |
| 956 | subtree has no particular ordering relationship to either. (The |
| 957 | dividing line between the subtree sizes is based on trie relation.) |
| 958 | If we remove the last chunk of a given size from the interior of the |
| 959 | tree, we need to replace it with a leaf node. The tree ordering |
| 960 | rules permit a node to be replaced by any leaf below it. |
| 961 | |
| 962 | The smallest chunk in a tree (a common operation in a best-fit |
| 963 | allocator) can be found by walking a path to the leftmost leaf in |
| 964 | the tree. Unlike a usual binary tree, where we follow left child |
| 965 | pointers until we reach a null, here we follow the right child |
| 966 | pointer any time the left one is null, until we reach a leaf with |
| 967 | both child pointers null. The smallest chunk in the tree will be |
| 968 | somewhere along that path. |
| 969 | |
| 970 | The worst case number of steps to add, find, or remove a node is |
| 971 | bounded by the number of bits differentiating chunks within |
| 972 | bins. Under current bin calculations, this ranges from 6 up to 21 |
| 973 | (for 32 bit sizes) or up to 53 (for 64 bit sizes). The typical case |
| 974 | is of course much better. |
| 975 | */ |
| 976 | |
| 977 | struct malloc_tree_chunk { |
| 978 | /* The first four fields must be compatible with malloc_chunk */ |
| 979 | size_t prev_foot; |
| 980 | size_t head; |
| 981 | struct malloc_tree_chunk* fd; |
| 982 | struct malloc_tree_chunk* bk; |
| 983 | |
| 984 | struct malloc_tree_chunk* child[2]; |
| 985 | struct malloc_tree_chunk* parent; |
| 986 | bindex_t index; |
| 987 | }; |
| 988 | |
| 989 | typedef struct malloc_tree_chunk tchunk; |
| 990 | typedef struct malloc_tree_chunk* tchunkptr; |
| 991 | typedef struct malloc_tree_chunk* tbinptr; /* The type of bins of trees */ |
| 992 | |
| 993 | /* A little helper macro for trees */ |
| 994 | #define leftmost_child(t) ((t)->child[0] != 0? (t)->child[0] : (t)->child[1]) |
| 995 | |
| 996 | /* ----------------------------- Segments -------------------------------- */ |
| 997 | |
| 998 | /* |
| 999 | Each malloc space may include non-contiguous segments, held in a |
| 1000 | list headed by an embedded malloc_segment record representing the |
| 1001 | top-most space. Segments also include flags holding properties of |
| 1002 | the space. Large chunks that are directly allocated by mmap are not |
| 1003 | included in this list. They are instead independently created and |
| 1004 | destroyed without otherwise keeping track of them. |
| 1005 | |
| 1006 | Segment management mainly comes into play for spaces allocated by |
| 1007 | MMAP. Any call to MMAP might or might not return memory that is |
| 1008 | adjacent to an existing segment. MORECORE normally contiguously |
| 1009 | extends the current space, so this space is almost always adjacent, |
| 1010 | which is simpler and faster to deal with. (This is why MORECORE is |
| 1011 | used preferentially to MMAP when both are available -- see |
| 1012 | sys_alloc.) When allocating using MMAP, we don't use any of the |
| 1013 | hinting mechanisms (inconsistently) supported in various |
| 1014 | implementations of unix mmap, or distinguish reserving from |
| 1015 | committing memory. Instead, we just ask for space, and exploit |
| 1016 | contiguity when we get it. It is probably possible to do |
| 1017 | better than this on some systems, but no general scheme seems |
| 1018 | to be significantly better. |
| 1019 | |
| 1020 | Management entails a simpler variant of the consolidation scheme |
| 1021 | used for chunks to reduce fragmentation -- new adjacent memory is |
| 1022 | normally prepended or appended to an existing segment. However, |
| 1023 | there are limitations compared to chunk consolidation that mostly |
| 1024 | reflect the fact that segment processing is relatively infrequent |
| 1025 | (occurring only when getting memory from system) and that we |
| 1026 | don't expect to have huge numbers of segments: |
| 1027 | |
| 1028 | * Segments are not indexed, so traversal requires linear scans. (It |
| 1029 | would be possible to index these, but is not worth the extra |
| 1030 | overhead and complexity for most programs on most platforms.) |
| 1031 | * New segments are only appended to old ones when holding top-most |
| 1032 | memory; if they cannot be prepended to others, they are held in |
| 1033 | different segments. |
| 1034 | |
| 1035 | Except for the top-most segment of an mstate, each segment record |
| 1036 | is kept at the tail of its segment. Segments are added by pushing |
| 1037 | segment records onto the list headed by &mstate.seg for the |
| 1038 | containing mstate. |
| 1039 | |
| 1040 | Segment flags control allocation/merge/deallocation policies: |
| 1041 | * If EXTERN_BIT set, then we did not allocate this segment, |
| 1042 | and so should not try to deallocate or merge with others. |
| 1043 | (This currently holds only for the initial segment passed |
| 1044 | into create_mspace_with_base.) |
| 1045 | * If USE_MMAP_BIT set, the segment may be merged with |
| 1046 | other surrounding mmapped segments and trimmed/de-allocated |
| 1047 | using munmap. |
| 1048 | * If neither bit is set, then the segment was obtained using |
| 1049 | MORECORE so can be merged with surrounding MORECORE'd segments |
| 1050 | and deallocated/trimmed using MORECORE with negative arguments. |
| 1051 | */ |
| 1052 | |
| 1053 | struct malloc_segment { |
| 1054 | char* base; /* base address */ |
| 1055 | size_t size; /* allocated size */ |
| 1056 | struct malloc_segment* next; /* ptr to next segment */ |
| 1057 | flag_t sflags; /* mmap and extern flag */ |
| 1058 | }; |
| 1059 | |
| 1060 | #define is_mmapped_segment(S) ((S)->sflags & USE_MMAP_BIT) |
| 1061 | #define is_extern_segment(S) ((S)->sflags & EXTERN_BIT) |
| 1062 | |
| 1063 | typedef struct malloc_segment msegment; |
| 1064 | typedef struct malloc_segment* msegmentptr; |
| 1065 | |
| 1066 | /* ---------------------------- malloc_state ----------------------------- */ |
| 1067 | |
| 1068 | /* |
| 1069 | A malloc_state holds all of the bookkeeping for a space. |
| 1070 | The main fields are: |
| 1071 | |
| 1072 | Top |
| 1073 | The topmost chunk of the currently active segment. Its size is |
| 1074 | cached in topsize. The actual size of topmost space is |
| 1075 | topsize+TOP_FOOT_SIZE, which includes space reserved for adding |
| 1076 | fenceposts and segment records if necessary when getting more |
| 1077 | space from the system. The size at which to autotrim top is |
| 1078 | cached from mparams in trim_check, except that it is disabled if |
| 1079 | an autotrim fails. |
| 1080 | |
| 1081 | Designated victim (dv) |
| 1082 | This is the preferred chunk for servicing small requests that |
| 1083 | don't have exact fits. It is normally the chunk split off most |
| 1084 | recently to service another small request. Its size is cached in |
| 1085 | dvsize. The link fields of this chunk are not maintained since it |
| 1086 | is not kept in a bin. |
| 1087 | |
| 1088 | SmallBins |
| 1089 | An array of bin headers for free chunks. These bins hold chunks |
| 1090 | with sizes less than MIN_LARGE_SIZE bytes. Each bin contains |
| 1091 | chunks of all the same size, spaced 8 bytes apart. To simplify |
| 1092 | use in double-linked lists, each bin header acts as a malloc_chunk |
| 1093 | pointing to the real first node, if it exists (else pointing to |
| 1094 | itself). This avoids special-casing for headers. But to avoid |
| 1095 | waste, we allocate only the fd/bk pointers of bins, and then use |
| 1096 | repositioning tricks to treat these as the fields of a chunk. |
| 1097 | |
| 1098 | TreeBins |
| 1099 | Treebins are pointers to the roots of trees holding a range of |
| 1100 | sizes. There are 2 equally spaced treebins for each power of two |
| 1101 | from TREE_SHIFT to TREE_SHIFT+16. The last bin holds anything |
| 1102 | larger. |
| 1103 | |
| 1104 | Bin maps |
| 1105 | There is one bit map for small bins ("smallmap") and one for |
| 1106 | treebins ("treemap). Each bin sets its bit when non-empty, and |
| 1107 | clears the bit when empty. Bit operations are then used to avoid |
| 1108 | bin-by-bin searching -- nearly all "search" is done without ever |
| 1109 | looking at bins that won't be selected. The bit maps |
| 1110 | conservatively use 32 bits per map word, even if on 64bit system. |
| 1111 | For a good description of some of the bit-based techniques used |
| 1112 | here, see Henry S. Warren Jr's book "Hacker's Delight" (and |
| 1113 | supplement at http://hackersdelight.org/). Many of these are |
| 1114 | intended to reduce the branchiness of paths through malloc etc, as |
| 1115 | well as to reduce the number of memory locations read or written. |
| 1116 | |
| 1117 | Segments |
| 1118 | A list of segments headed by an embedded malloc_segment record |
| 1119 | representing the initial space. |
| 1120 | |
| 1121 | Address check support |
| 1122 | The least_addr field is the least address ever obtained from |
| 1123 | MORECORE or MMAP. Attempted frees and reallocs of any address less |
| 1124 | than this are trapped (unless INSECURE is defined). |
| 1125 | |
| 1126 | Magic tag |
| 1127 | A cross-check field that should always hold same value as mparams.magic. |
| 1128 | |
| 1129 | Max allowed footprint |
| 1130 | The maximum allowed bytes to allocate from system (zero means no limit) |
| 1131 | |
| 1132 | Flags |
| 1133 | Bits recording whether to use MMAP, locks, or contiguous MORECORE |
| 1134 | |
| 1135 | Statistics |
| 1136 | Each space keeps track of current and maximum system memory |
| 1137 | obtained via MORECORE or MMAP. |
| 1138 | |
| 1139 | Trim support |
| 1140 | Fields holding the amount of unused topmost memory that should trigger |
| 1141 | trimming, and a counter to force periodic scanning to release unused |
| 1142 | non-topmost segments. |
| 1143 | |
| 1144 | Locking |
| 1145 | If USE_LOCKS is defined, the "mutex" lock is acquired and released |
| 1146 | around every public call using this mspace. |
| 1147 | |
| 1148 | Extension support |
| 1149 | A void* pointer and a size_t field that can be used to help implement |
| 1150 | extensions to this malloc. |
| 1151 | */ |
| 1152 | |
| 1153 | /* Bin types, widths and sizes */ |
| 1154 | #define NSMALLBINS (32U) |
| 1155 | #define NTREEBINS (32U) |
| 1156 | #define SMALLBIN_SHIFT (3U) |
| 1157 | #define SMALLBIN_WIDTH (SIZE_T_ONE << SMALLBIN_SHIFT) |
| 1158 | #define TREEBIN_SHIFT (8U) |
| 1159 | #define MIN_LARGE_SIZE (SIZE_T_ONE << TREEBIN_SHIFT) |
| 1160 | #define MAX_SMALL_SIZE (MIN_LARGE_SIZE - SIZE_T_ONE) |
| 1161 | #define MAX_SMALL_REQUEST (MAX_SMALL_SIZE - CHUNK_ALIGN_MASK - CHUNK_OVERHEAD) |
| 1162 | |
| 1163 | struct malloc_state { |
| 1164 | binmap_t smallmap; |
| 1165 | binmap_t treemap; |
| 1166 | size_t dvsize; |
| 1167 | size_t topsize; |
| 1168 | char* least_addr; |
| 1169 | mchunkptr dv; |
| 1170 | mchunkptr top; |
| 1171 | size_t trim_check; |
| 1172 | size_t release_checks; |
| 1173 | size_t magic; |
| 1174 | mchunkptr smallbins[(NSMALLBINS+1)*2]; |
| 1175 | tbinptr treebins[NTREEBINS]; |
| 1176 | size_t footprint; |
| 1177 | size_t max_footprint; |
| 1178 | size_t footprint_limit; /* zero means no limit */ |
| 1179 | flag_t mflags; |
| 1180 | #if USE_LOCKS |
| 1181 | MLOCK_T mutex; /* locate lock among fields that rarely change */ |
| 1182 | #endif /* USE_LOCKS */ |
| 1183 | msegment seg; |
| 1184 | void* extp; /* Unused but available for extensions */ |
| 1185 | size_t exts; |
| 1186 | }; |
| 1187 | |
| 1188 | typedef struct malloc_state* mstate; |
| 1189 | |
| 1190 | /* ------------- Global malloc_state and malloc_params ------------------- */ |
| 1191 | |
| 1192 | /* |
| 1193 | malloc_params holds global properties, including those that can be |
| 1194 | dynamically set using mallopt. There is a single instance, mparams, |
| 1195 | initialized in init_mparams. Note that the non-zeroness of "magic" |
| 1196 | also serves as an initialization flag. |
| 1197 | */ |
| 1198 | |
| 1199 | struct malloc_params { |
| 1200 | size_t magic; |
| 1201 | size_t page_size; |
| 1202 | size_t granularity; |
| 1203 | size_t mmap_threshold; |
| 1204 | size_t trim_threshold; |
| 1205 | flag_t default_mflags; |
| 1206 | }; |
| 1207 | |
| 1208 | static struct malloc_params mparams; |
| 1209 | |
| 1210 | /* Ensure mparams initialized */ |
| 1211 | #define ensure_initialization() (void)(mparams.magic != 0 || init_mparams()) |
| 1212 | |
| 1213 | #if !ONLY_MSPACES |
| 1214 | |
| 1215 | /* The global malloc_state used for all non-"mspace" calls */ |
| 1216 | static struct malloc_state _gm_; |
| 1217 | #define gm (&_gm_) |
| 1218 | #define is_global(M) ((M) == &_gm_) |
| 1219 | |
| 1220 | #endif /* !ONLY_MSPACES */ |
| 1221 | |
| 1222 | #define is_initialized(M) ((M)->top != 0) |
| 1223 | |
| 1224 | /* -------------------------- system alloc setup ------------------------- */ |
| 1225 | |
| 1226 | /* Operations on mflags */ |
| 1227 | |
| 1228 | #define use_lock(M) ((M)->mflags & USE_LOCK_BIT) |
| 1229 | #define enable_lock(M) ((M)->mflags |= USE_LOCK_BIT) |
| 1230 | #if USE_LOCKS |
| 1231 | #define disable_lock(M) ((M)->mflags &= ~USE_LOCK_BIT) |
| 1232 | #else |
| 1233 | #define disable_lock(M) |
| 1234 | #endif |
| 1235 | |
| 1236 | #define use_mmap(M) ((M)->mflags & USE_MMAP_BIT) |
| 1237 | #define enable_mmap(M) ((M)->mflags |= USE_MMAP_BIT) |
| 1238 | #if HAVE_MMAP |
| 1239 | #define disable_mmap(M) ((M)->mflags &= ~USE_MMAP_BIT) |
| 1240 | #else |
| 1241 | #define disable_mmap(M) |
| 1242 | #endif |
| 1243 | |
| 1244 | #define use_noncontiguous(M) ((M)->mflags & USE_NONCONTIGUOUS_BIT) |
| 1245 | #define disable_contiguous(M) ((M)->mflags |= USE_NONCONTIGUOUS_BIT) |
| 1246 | #define use_noexpand(M) ((M)->mflags & USE_NOEXPAND_BIT) |
| 1247 | #define disable_expand(M) ((M)->mflags |= USE_NOEXPAND_BIT) |
| 1248 | #define use_trace(M) ((M)->mflags & USE_TRACE_BIT) |
| 1249 | #define enable_trace(M) ((M)->mflags |= USE_TRACE_BIT) |
| 1250 | #define disable_trace(M) ((M)->mflags |= USE_TRACE_BIT) |
| 1251 | |
| 1252 | #define set_lock(M,L)\ |
| 1253 | ((M)->mflags = (L)?\ |
| 1254 | ((M)->mflags | USE_LOCK_BIT) :\ |
| 1255 | ((M)->mflags & ~USE_LOCK_BIT)) |
| 1256 | |
| 1257 | /* page-align a size */ |
| 1258 | #define page_align(S)\ |
| 1259 | (((S) + (mparams.page_size - SIZE_T_ONE)) & ~(mparams.page_size - SIZE_T_ONE)) |
| 1260 | |
| 1261 | /* granularity-align a size */ |
| 1262 | #define granularity_align(S)\ |
| 1263 | (((S) + (mparams.granularity - SIZE_T_ONE))\ |
| 1264 | & ~(mparams.granularity - SIZE_T_ONE)) |
| 1265 | |
| 1266 | |
| 1267 | /* For mmap, use granularity alignment on windows, else page-align */ |
| 1268 | #ifdef WIN32 |
| 1269 | #define mmap_align(S) granularity_align(S) |
| 1270 | #else |
| 1271 | #define mmap_align(S) page_align(S) |
| 1272 | #endif |
| 1273 | |
| 1274 | /* For sys_alloc, enough padding to ensure can malloc request on success */ |
| 1275 | #define SYS_ALLOC_PADDING (TOP_FOOT_SIZE + MALLOC_ALIGNMENT) |
| 1276 | |
| 1277 | #define is_page_aligned(S)\ |
| 1278 | (((size_t)(S) & (mparams.page_size - SIZE_T_ONE)) == 0) |
| 1279 | #define is_granularity_aligned(S)\ |
| 1280 | (((size_t)(S) & (mparams.granularity - SIZE_T_ONE)) == 0) |
| 1281 | |
| 1282 | /* True if segment S holds address A */ |
| 1283 | #define segment_holds(S, A)\ |
| 1284 | ((char*)(A) >= S->base && (char*)(A) < S->base + S->size) |
| 1285 | |
| 1286 | /* Return segment holding given address */ |
| 1287 | static msegmentptr segment_holding(mstate m, char* addr) { |
| 1288 | msegmentptr sp = &m->seg; |
| 1289 | for (;;) { |
| 1290 | if (addr >= sp->base && addr < sp->base + sp->size) |
| 1291 | return sp; |
| 1292 | if ((sp = sp->next) == 0) |
| 1293 | return 0; |
| 1294 | } |
| 1295 | } |
| 1296 | |
| 1297 | /* Return true if segment contains a segment link */ |
| 1298 | static int has_segment_link(mstate m, msegmentptr ss) { |
| 1299 | msegmentptr sp = &m->seg; |
| 1300 | for (;;) { |
| 1301 | if ((char*)sp >= ss->base && (char*)sp < ss->base + ss->size) |
| 1302 | return 1; |
| 1303 | if ((sp = sp->next) == 0) |
| 1304 | return 0; |
| 1305 | } |
| 1306 | } |
| 1307 | |
| 1308 | #ifndef MORECORE_CANNOT_TRIM |
| 1309 | #define should_trim(M,s) ((s) > (M)->trim_check) |
| 1310 | #else /* MORECORE_CANNOT_TRIM */ |
| 1311 | #define should_trim(M,s) (0) |
| 1312 | #endif /* MORECORE_CANNOT_TRIM */ |
| 1313 | |
| 1314 | /* |
| 1315 | TOP_FOOT_SIZE is padding at the end of a segment, including space |
| 1316 | that may be needed to place segment records and fenceposts when new |
| 1317 | noncontiguous segments are added. |
| 1318 | */ |
| 1319 | #define TOP_FOOT_SIZE\ |
| 1320 | (align_offset(chunk2mem(0))+pad_request(sizeof(struct malloc_segment))+MIN_CHUNK_SIZE) |
| 1321 | |
| 1322 | |
| 1323 | /* ------------------------------- Hooks -------------------------------- */ |
| 1324 | |
| 1325 | /* |
| 1326 | PREACTION should be defined to return 0 on success, and nonzero on |
| 1327 | failure. If you are not using locking, you can redefine these to do |
| 1328 | anything you like. |
| 1329 | */ |
| 1330 | |
| 1331 | #if USE_LOCKS |
| 1332 | #define PREACTION(M) ((use_lock(M))? ACQUIRE_LOCK(&(M)->mutex) : 0) |
| 1333 | #define POSTACTION(M) { if (use_lock(M)) RELEASE_LOCK(&(M)->mutex); } |
| 1334 | #else /* USE_LOCKS */ |
| 1335 | |
| 1336 | #ifndef PREACTION |
| 1337 | #define PREACTION(M) (0) |
| 1338 | #endif /* PREACTION */ |
| 1339 | |
| 1340 | #ifndef POSTACTION |
| 1341 | #define POSTACTION(M) |
| 1342 | #endif /* POSTACTION */ |
| 1343 | |
| 1344 | #endif /* USE_LOCKS */ |
| 1345 | |
| 1346 | /* |
| 1347 | CORRUPTION_ERROR_ACTION is triggered upon detected bad addresses. |
| 1348 | USAGE_ERROR_ACTION is triggered on detected bad frees and |
| 1349 | reallocs. The argument p is an address that might have triggered the |
| 1350 | fault. It is ignored by the two predefined actions, but might be |
| 1351 | useful in custom actions that try to help diagnose errors. |
| 1352 | */ |
| 1353 | |
| 1354 | #if PROCEED_ON_ERROR |
| 1355 | |
| 1356 | /* A count of the number of corruption errors causing resets */ |
| 1357 | int malloc_corruption_error_count; |
| 1358 | |
| 1359 | /* default corruption action */ |
| 1360 | static void reset_on_error(mstate m); |
| 1361 | |
| 1362 | #define CORRUPTION_ERROR_ACTION(m) reset_on_error(m) |
| 1363 | #define USAGE_ERROR_ACTION(m, p) |
| 1364 | |
| 1365 | #else /* PROCEED_ON_ERROR */ |
| 1366 | |
| 1367 | #ifndef CORRUPTION_ERROR_ACTION |
| 1368 | #define CORRUPTION_ERROR_ACTION(m) DLM_ABORT |
| 1369 | #endif /* CORRUPTION_ERROR_ACTION */ |
| 1370 | |
| 1371 | #ifndef USAGE_ERROR_ACTION |
| 1372 | #define USAGE_ERROR_ACTION(m,p) DLM_ABORT |
| 1373 | #endif /* USAGE_ERROR_ACTION */ |
| 1374 | |
| 1375 | #endif /* PROCEED_ON_ERROR */ |
| 1376 | |
| 1377 | |
| 1378 | /* -------------------------- Debugging setup ---------------------------- */ |
| 1379 | |
| 1380 | #if ! DEBUG |
| 1381 | |
| 1382 | #define check_free_chunk(M,P) |
| 1383 | #define check_inuse_chunk(M,P) |
| 1384 | #define check_malloced_chunk(M,P,N) |
| 1385 | #define check_mmapped_chunk(M,P) |
| 1386 | #define check_malloc_state(M) |
| 1387 | #define check_top_chunk(M,P) |
| 1388 | |
| 1389 | #else /* DEBUG */ |
| 1390 | #define check_free_chunk(M,P) do_check_free_chunk(M,P) |
| 1391 | #define check_inuse_chunk(M,P) do_check_inuse_chunk(M,P) |
| 1392 | #define check_top_chunk(M,P) do_check_top_chunk(M,P) |
| 1393 | #define check_malloced_chunk(M,P,N) do_check_malloced_chunk(M,P,N) |
| 1394 | #define check_mmapped_chunk(M,P) do_check_mmapped_chunk(M,P) |
| 1395 | #define check_malloc_state(M) do_check_malloc_state(M) |
| 1396 | |
| 1397 | static void do_check_any_chunk(mstate m, mchunkptr p); |
| 1398 | static void do_check_top_chunk(mstate m, mchunkptr p); |
| 1399 | static void do_check_mmapped_chunk(mstate m, mchunkptr p); |
| 1400 | static void do_check_inuse_chunk(mstate m, mchunkptr p); |
| 1401 | static void do_check_free_chunk(mstate m, mchunkptr p); |
| 1402 | static void do_check_malloced_chunk(mstate m, void* mem, size_t s); |
| 1403 | static void do_check_tree(mstate m, tchunkptr t); |
| 1404 | static void do_check_treebin(mstate m, bindex_t i); |
| 1405 | static void do_check_smallbin(mstate m, bindex_t i); |
| 1406 | static void do_check_malloc_state(mstate m); |
| 1407 | static int bin_find(mstate m, mchunkptr x); |
| 1408 | static size_t traverse_and_check(mstate m); |
| 1409 | #endif /* DEBUG */ |
| 1410 | |
| 1411 | /* ---------------------------- Indexing Bins ---------------------------- */ |
| 1412 | |
| 1413 | #define is_small(s) (((s) >> SMALLBIN_SHIFT) < NSMALLBINS) |
| 1414 | #define small_index(s) (bindex_t)((s) >> SMALLBIN_SHIFT) |
| 1415 | #define small_index2size(i) ((i) << SMALLBIN_SHIFT) |
| 1416 | #define MIN_SMALL_INDEX (small_index(MIN_CHUNK_SIZE)) |
| 1417 | |
| 1418 | /* addressing by index. See above about smallbin repositioning */ |
| 1419 | #define smallbin_at(M, i) ((sbinptr)((char*)&((M)->smallbins[(i)<<1]))) |
| 1420 | #define treebin_at(M,i) (&((M)->treebins[i])) |
| 1421 | |
| 1422 | /* assign tree index for size S to variable I. Use x86 asm if possible */ |
| 1423 | #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) |
| 1424 | #define compute_tree_index(S, I)\ |
| 1425 | {\ |
| 1426 | unsigned int X = S >> TREEBIN_SHIFT;\ |
| 1427 | if (X == 0)\ |
| 1428 | I = 0;\ |
| 1429 | else if (X > 0xFFFF)\ |
| 1430 | I = NTREEBINS-1;\ |
| 1431 | else {\ |
| 1432 | unsigned int K = (unsigned) sizeof(X)*__CHAR_BIT__ - 1 - (unsigned) __builtin_clz(X); \ |
| 1433 | I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\ |
| 1434 | }\ |
| 1435 | } |
| 1436 | |
| 1437 | #elif defined (__INTEL_COMPILER) |
| 1438 | #define compute_tree_index(S, I)\ |
| 1439 | {\ |
| 1440 | size_t X = S >> TREEBIN_SHIFT;\ |
| 1441 | if (X == 0)\ |
| 1442 | I = 0;\ |
| 1443 | else if (X > 0xFFFF)\ |
| 1444 | I = NTREEBINS-1;\ |
| 1445 | else {\ |
| 1446 | unsigned int K = _bit_scan_reverse (X); \ |
| 1447 | I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\ |
| 1448 | }\ |
| 1449 | } |
| 1450 | |
| 1451 | #elif defined(_MSC_VER) && _MSC_VER>=1300 |
| 1452 | #define compute_tree_index(S, I)\ |
| 1453 | {\ |
| 1454 | size_t X = S >> TREEBIN_SHIFT;\ |
| 1455 | if (X == 0)\ |
| 1456 | I = 0;\ |
| 1457 | else if (X > 0xFFFF)\ |
| 1458 | I = NTREEBINS-1;\ |
| 1459 | else {\ |
| 1460 | unsigned int K;\ |
| 1461 | _BitScanReverse((DWORD *) &K, (DWORD) X);\ |
| 1462 | I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\ |
| 1463 | }\ |
| 1464 | } |
| 1465 | |
| 1466 | #else /* GNUC */ |
| 1467 | #define compute_tree_index(S, I)\ |
| 1468 | {\ |
| 1469 | size_t X = S >> TREEBIN_SHIFT;\ |
| 1470 | if (X == 0)\ |
| 1471 | I = 0;\ |
| 1472 | else if (X > 0xFFFF)\ |
| 1473 | I = NTREEBINS-1;\ |
| 1474 | else {\ |
| 1475 | unsigned int Y = (unsigned int)X;\ |
| 1476 | unsigned int N = ((Y - 0x100) >> 16) & 8;\ |
| 1477 | unsigned int K = (((Y <<= N) - 0x1000) >> 16) & 4;\ |
| 1478 | N += K;\ |
| 1479 | N += K = (((Y <<= K) - 0x4000) >> 16) & 2;\ |
| 1480 | K = 14 - N + ((Y <<= K) >> 15);\ |
| 1481 | I = (K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1));\ |
| 1482 | }\ |
| 1483 | } |
| 1484 | #endif /* GNUC */ |
| 1485 | |
| 1486 | /* Bit representing maximum resolved size in a treebin at i */ |
| 1487 | #define bit_for_tree_index(i) \ |
| 1488 | (i == NTREEBINS-1)? (SIZE_T_BITSIZE-1) : (((i) >> 1) + TREEBIN_SHIFT - 2) |
| 1489 | |
| 1490 | /* Shift placing maximum resolved bit in a treebin at i as sign bit */ |
| 1491 | #define leftshift_for_tree_index(i) \ |
| 1492 | ((i == NTREEBINS-1)? 0 : \ |
| 1493 | ((SIZE_T_BITSIZE-SIZE_T_ONE) - (((i) >> 1) + TREEBIN_SHIFT - 2))) |
| 1494 | |
| 1495 | /* The size of the smallest chunk held in bin with index i */ |
| 1496 | #define minsize_for_tree_index(i) \ |
| 1497 | ((SIZE_T_ONE << (((i) >> 1) + TREEBIN_SHIFT)) | \ |
| 1498 | (((size_t)((i) & SIZE_T_ONE)) << (((i) >> 1) + TREEBIN_SHIFT - 1))) |
| 1499 | |
| 1500 | |
| 1501 | /* ------------------------ Operations on bin maps ----------------------- */ |
| 1502 | |
| 1503 | /* bit corresponding to given index */ |
| 1504 | #define idx2bit(i) ((binmap_t)(1) << (i)) |
| 1505 | |
| 1506 | /* Mark/Clear bits with given index */ |
| 1507 | #define mark_smallmap(M,i) ((M)->smallmap |= idx2bit(i)) |
| 1508 | #define clear_smallmap(M,i) ((M)->smallmap &= ~idx2bit(i)) |
| 1509 | #define smallmap_is_marked(M,i) ((M)->smallmap & idx2bit(i)) |
| 1510 | |
| 1511 | #define mark_treemap(M,i) ((M)->treemap |= idx2bit(i)) |
| 1512 | #define clear_treemap(M,i) ((M)->treemap &= ~idx2bit(i)) |
| 1513 | #define treemap_is_marked(M,i) ((M)->treemap & idx2bit(i)) |
| 1514 | |
| 1515 | /* isolate the least set bit of a bitmap */ |
| 1516 | #define least_bit(x) ((x) & -(x)) |
| 1517 | |
| 1518 | /* mask with all bits to left of least bit of x on */ |
| 1519 | #define left_bits(x) ((x<<1) | -(x<<1)) |
| 1520 | |
| 1521 | /* mask with all bits to left of or equal to least bit of x on */ |
| 1522 | #define same_or_left_bits(x) ((x) | -(x)) |
| 1523 | |
| 1524 | /* index corresponding to given bit. Use x86 asm if possible */ |
| 1525 | |
| 1526 | #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) |
| 1527 | #define compute_bit2idx(X, I)\ |
| 1528 | {\ |
| 1529 | unsigned int J;\ |
| 1530 | J = __builtin_ctz(X); \ |
| 1531 | I = (bindex_t)J;\ |
| 1532 | } |
| 1533 | |
| 1534 | #elif defined (__INTEL_COMPILER) |
| 1535 | #define compute_bit2idx(X, I)\ |
| 1536 | {\ |
| 1537 | unsigned int J;\ |
| 1538 | J = _bit_scan_forward (X); \ |
| 1539 | I = (bindex_t)J;\ |
| 1540 | } |
| 1541 | |
| 1542 | #elif defined(_MSC_VER) && _MSC_VER>=1300 |
| 1543 | #define compute_bit2idx(X, I)\ |
| 1544 | {\ |
| 1545 | unsigned int J;\ |
| 1546 | _BitScanForward((DWORD *) &J, X);\ |
| 1547 | I = (bindex_t)J;\ |
| 1548 | } |
| 1549 | |
| 1550 | #elif USE_BUILTIN_FFS |
| 1551 | #define compute_bit2idx(X, I) I = ffs(X)-1 |
| 1552 | |
| 1553 | #else |
| 1554 | #define compute_bit2idx(X, I)\ |
| 1555 | {\ |
| 1556 | unsigned int Y = X - 1;\ |
| 1557 | unsigned int K = Y >> (16-4) & 16;\ |
| 1558 | unsigned int N = K; Y >>= K;\ |
| 1559 | N += K = Y >> (8-3) & 8; Y >>= K;\ |
| 1560 | N += K = Y >> (4-2) & 4; Y >>= K;\ |
| 1561 | N += K = Y >> (2-1) & 2; Y >>= K;\ |
| 1562 | N += K = Y >> (1-0) & 1; Y >>= K;\ |
| 1563 | I = (bindex_t)(N + Y);\ |
| 1564 | } |
| 1565 | #endif /* GNUC */ |
| 1566 | |
| 1567 | |
| 1568 | /* ----------------------- Runtime Check Support ------------------------- */ |
| 1569 | |
| 1570 | /* |
| 1571 | For security, the main invariant is that malloc/free/etc never |
| 1572 | writes to a static address other than malloc_state, unless static |
| 1573 | malloc_state itself has been corrupted, which cannot occur via |
| 1574 | malloc (because of these checks). In essence this means that we |
| 1575 | believe all pointers, sizes, maps etc held in malloc_state, but |
| 1576 | check all of those linked or offsetted from other embedded data |
| 1577 | structures. These checks are interspersed with main code in a way |
| 1578 | that tends to minimize their run-time cost. |
| 1579 | |
| 1580 | When FOOTERS is defined, in addition to range checking, we also |
| 1581 | verify footer fields of inuse chunks, which can be used guarantee |
| 1582 | that the mstate controlling malloc/free is intact. This is a |
| 1583 | streamlined version of the approach described by William Robertson |
| 1584 | et al in "Run-time Detection of Heap-based Overflows" LISA'03 |
| 1585 | http://www.usenix.org/events/lisa03/tech/robertson.html The footer |
| 1586 | of an inuse chunk holds the xor of its mstate and a random seed, |
| 1587 | that is checked upon calls to free() and realloc(). This is |
Paul Vinciguerra | ec11b13 | 2018-09-24 05:25:00 -0700 | [diff] [blame] | 1588 | (probabilistically) unguessable from outside the program, but can be |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 1589 | computed by any code successfully malloc'ing any chunk, so does not |
| 1590 | itself provide protection against code that has already broken |
| 1591 | security through some other means. Unlike Robertson et al, we |
| 1592 | always dynamically check addresses of all offset chunks (previous, |
| 1593 | next, etc). This turns out to be cheaper than relying on hashes. |
| 1594 | */ |
| 1595 | |
| 1596 | #if !INSECURE |
| 1597 | /* Check if address a is at least as high as any from MORECORE or MMAP */ |
| 1598 | #define ok_address(M, a) ((char*)(a) >= (M)->least_addr) |
| 1599 | /* Check if address of next chunk n is higher than base chunk p */ |
| 1600 | #define ok_next(p, n) ((char*)(p) < (char*)(n)) |
| 1601 | /* Check if p has inuse status */ |
| 1602 | #define ok_inuse(p) is_inuse(p) |
| 1603 | /* Check if p has its pinuse bit on */ |
| 1604 | #define ok_pinuse(p) pinuse(p) |
| 1605 | |
| 1606 | #else /* !INSECURE */ |
| 1607 | #define ok_address(M, a) (1) |
| 1608 | #define ok_next(b, n) (1) |
| 1609 | #define ok_inuse(p) (1) |
| 1610 | #define ok_pinuse(p) (1) |
| 1611 | #endif /* !INSECURE */ |
| 1612 | |
| 1613 | #if (FOOTERS && !INSECURE) |
| 1614 | /* Check if (alleged) mstate m has expected magic field */ |
Neale Ranns | a88c916 | 2018-08-06 08:16:29 -0400 | [diff] [blame] | 1615 | static inline int |
| 1616 | ok_magic (const mstate m) |
| 1617 | { |
| 1618 | return (m->magic == mparams.magic); |
| 1619 | } |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 1620 | #else /* (FOOTERS && !INSECURE) */ |
| 1621 | #define ok_magic(M) (1) |
| 1622 | #endif /* (FOOTERS && !INSECURE) */ |
| 1623 | |
| 1624 | /* In gcc, use __builtin_expect to minimize impact of checks */ |
| 1625 | #if !INSECURE |
| 1626 | #if defined(__GNUC__) && __GNUC__ >= 3 |
| 1627 | #define RTCHECK(e) __builtin_expect(e, 1) |
| 1628 | #else /* GNUC */ |
| 1629 | #define RTCHECK(e) (e) |
| 1630 | #endif /* GNUC */ |
| 1631 | #else /* !INSECURE */ |
| 1632 | #define RTCHECK(e) (1) |
| 1633 | #endif /* !INSECURE */ |
| 1634 | |
| 1635 | /* macros to set up inuse chunks with or without footers */ |
| 1636 | |
| 1637 | #if !FOOTERS |
| 1638 | |
| 1639 | #define mark_inuse_foot(M,p,s) |
| 1640 | |
| 1641 | /* Macros for setting head/foot of non-mmapped chunks */ |
| 1642 | |
| 1643 | /* Set cinuse bit and pinuse bit of next chunk */ |
| 1644 | #define set_inuse(M,p,s)\ |
| 1645 | ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\ |
| 1646 | ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT) |
| 1647 | |
| 1648 | /* Set cinuse and pinuse of this chunk and pinuse of next chunk */ |
| 1649 | #define set_inuse_and_pinuse(M,p,s)\ |
| 1650 | ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\ |
| 1651 | ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT) |
| 1652 | |
| 1653 | /* Set size, cinuse and pinuse bit of this chunk */ |
| 1654 | #define set_size_and_pinuse_of_inuse_chunk(M, p, s)\ |
| 1655 | ((p)->head = (s|PINUSE_BIT|CINUSE_BIT)) |
| 1656 | |
| 1657 | #else /* FOOTERS */ |
| 1658 | |
| 1659 | /* Set foot of inuse chunk to be xor of mstate and seed */ |
| 1660 | #define mark_inuse_foot(M,p,s)\ |
| 1661 | (((mchunkptr)((char*)(p) + (s)))->prev_foot = ((size_t)(M) ^ mparams.magic)) |
| 1662 | |
| 1663 | #define get_mstate_for(p)\ |
| 1664 | ((mstate)(((mchunkptr)((char*)(p) +\ |
| 1665 | (chunksize(p))))->prev_foot ^ mparams.magic)) |
| 1666 | |
| 1667 | #define set_inuse(M,p,s)\ |
| 1668 | ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\ |
| 1669 | (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT), \ |
| 1670 | mark_inuse_foot(M,p,s)) |
| 1671 | |
| 1672 | #define set_inuse_and_pinuse(M,p,s)\ |
| 1673 | ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\ |
| 1674 | (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT),\ |
| 1675 | mark_inuse_foot(M,p,s)) |
| 1676 | |
| 1677 | #define set_size_and_pinuse_of_inuse_chunk(M, p, s)\ |
| 1678 | ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\ |
| 1679 | mark_inuse_foot(M, p, s)) |
| 1680 | |
| 1681 | #endif /* !FOOTERS */ |
| 1682 | |
| 1683 | /* ---------------------------- setting mparams -------------------------- */ |
| 1684 | |
| 1685 | #if LOCK_AT_FORK |
| 1686 | static void pre_fork(void) { ACQUIRE_LOCK(&(gm)->mutex); } |
| 1687 | static void post_fork_parent(void) { RELEASE_LOCK(&(gm)->mutex); } |
| 1688 | static void post_fork_child(void) { INITIAL_LOCK(&(gm)->mutex); } |
| 1689 | #endif /* LOCK_AT_FORK */ |
| 1690 | |
| 1691 | /* Initialize mparams */ |
| 1692 | static int init_mparams(void) { |
| 1693 | #ifdef NEED_GLOBAL_LOCK_INIT |
| 1694 | if (malloc_global_mutex_status <= 0) |
| 1695 | init_malloc_global_mutex(); |
| 1696 | #endif |
| 1697 | |
| 1698 | ACQUIRE_MALLOC_GLOBAL_LOCK(); |
| 1699 | if (mparams.magic == 0) { |
| 1700 | size_t magic; |
| 1701 | size_t psize; |
| 1702 | size_t gsize; |
| 1703 | |
| 1704 | #ifndef WIN32 |
| 1705 | psize = malloc_getpagesize; |
| 1706 | gsize = ((DEFAULT_GRANULARITY != 0)? DEFAULT_GRANULARITY : psize); |
| 1707 | #else /* WIN32 */ |
| 1708 | { |
| 1709 | SYSTEM_INFO system_info; |
| 1710 | GetSystemInfo(&system_info); |
| 1711 | psize = system_info.dwPageSize; |
| 1712 | gsize = ((DEFAULT_GRANULARITY != 0)? |
| 1713 | DEFAULT_GRANULARITY : system_info.dwAllocationGranularity); |
| 1714 | } |
| 1715 | #endif /* WIN32 */ |
| 1716 | |
| 1717 | /* Sanity-check configuration: |
| 1718 | size_t must be unsigned and as wide as pointer type. |
| 1719 | ints must be at least 4 bytes. |
| 1720 | alignment must be at least 8. |
| 1721 | Alignment, min chunk size, and page size must all be powers of 2. |
| 1722 | */ |
| 1723 | if ((sizeof(size_t) != sizeof(char*)) || |
| 1724 | (MAX_SIZE_T < MIN_CHUNK_SIZE) || |
| 1725 | (sizeof(int) < 4) || |
| 1726 | (MALLOC_ALIGNMENT < (size_t)8U) || |
| 1727 | ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-SIZE_T_ONE)) != 0) || |
| 1728 | ((MCHUNK_SIZE & (MCHUNK_SIZE-SIZE_T_ONE)) != 0) || |
| 1729 | ((gsize & (gsize-SIZE_T_ONE)) != 0) || |
| 1730 | ((psize & (psize-SIZE_T_ONE)) != 0)) |
| 1731 | DLM_ABORT; |
| 1732 | mparams.granularity = gsize; |
| 1733 | mparams.page_size = psize; |
| 1734 | mparams.mmap_threshold = DEFAULT_MMAP_THRESHOLD; |
| 1735 | mparams.trim_threshold = DEFAULT_TRIM_THRESHOLD; |
| 1736 | #if MORECORE_CONTIGUOUS |
| 1737 | mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT; |
| 1738 | #else /* MORECORE_CONTIGUOUS */ |
| 1739 | mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT|USE_NONCONTIGUOUS_BIT; |
| 1740 | #endif /* MORECORE_CONTIGUOUS */ |
| 1741 | |
| 1742 | #if !ONLY_MSPACES |
| 1743 | /* Set up lock for main malloc area */ |
| 1744 | gm->mflags = mparams.default_mflags; |
| 1745 | (void)INITIAL_LOCK(&gm->mutex); |
| 1746 | #endif |
| 1747 | #if LOCK_AT_FORK |
| 1748 | pthread_atfork(&pre_fork, &post_fork_parent, &post_fork_child); |
| 1749 | #endif |
| 1750 | |
| 1751 | { |
Florin Coras | d3ca8ff | 2018-07-28 04:53:30 -0700 | [diff] [blame] | 1752 | #ifndef DLM_MAGIC_CONSTANT |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 1753 | #if USE_DEV_RANDOM |
| 1754 | int fd; |
| 1755 | unsigned char buf[sizeof(size_t)]; |
| 1756 | /* Try to use /dev/urandom, else fall back on using time */ |
| 1757 | if ((fd = open("/dev/urandom", O_RDONLY)) >= 0 && |
| 1758 | read(fd, buf, sizeof(buf)) == sizeof(buf)) { |
| 1759 | magic = *((size_t *) buf); |
| 1760 | close(fd); |
| 1761 | } |
| 1762 | else |
| 1763 | #endif /* USE_DEV_RANDOM */ |
| 1764 | #ifdef WIN32 |
| 1765 | magic = (size_t)(GetTickCount() ^ (size_t)0x55555555U); |
| 1766 | #elif defined(LACKS_TIME_H) |
| 1767 | magic = (size_t)&magic ^ (size_t)0x55555555U; |
| 1768 | #else |
| 1769 | magic = (size_t)(time(0) ^ (size_t)0x55555555U); |
| 1770 | #endif |
| 1771 | magic |= (size_t)8U; /* ensure nonzero */ |
| 1772 | magic &= ~(size_t)7U; /* improve chances of fault for bad values */ |
Florin Coras | d3ca8ff | 2018-07-28 04:53:30 -0700 | [diff] [blame] | 1773 | #else |
Florin Coras | d055475 | 2018-07-27 11:30:46 -0700 | [diff] [blame] | 1774 | magic = DLM_MAGIC_CONSTANT; |
| 1775 | #endif |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 1776 | /* Until memory modes commonly available, use volatile-write */ |
| 1777 | (*(volatile size_t *)(&(mparams.magic))) = magic; |
| 1778 | } |
| 1779 | } |
| 1780 | |
| 1781 | RELEASE_MALLOC_GLOBAL_LOCK(); |
| 1782 | return 1; |
| 1783 | } |
| 1784 | |
| 1785 | /* support for mallopt */ |
| 1786 | static int change_mparam(int param_number, int value) { |
| 1787 | size_t val; |
| 1788 | ensure_initialization(); |
| 1789 | val = (value == -1)? MAX_SIZE_T : (size_t)value; |
| 1790 | switch(param_number) { |
| 1791 | case M_TRIM_THRESHOLD: |
| 1792 | mparams.trim_threshold = val; |
| 1793 | return 1; |
| 1794 | case M_GRANULARITY: |
| 1795 | if (val >= mparams.page_size && ((val & (val-1)) == 0)) { |
| 1796 | mparams.granularity = val; |
| 1797 | return 1; |
| 1798 | } |
| 1799 | else |
| 1800 | return 0; |
| 1801 | case M_MMAP_THRESHOLD: |
| 1802 | mparams.mmap_threshold = val; |
| 1803 | return 1; |
| 1804 | default: |
| 1805 | return 0; |
| 1806 | } |
| 1807 | } |
| 1808 | |
| 1809 | #if DEBUG |
| 1810 | /* ------------------------- Debugging Support --------------------------- */ |
| 1811 | |
| 1812 | /* Check properties of any chunk, whether free, inuse, mmapped etc */ |
| 1813 | static void do_check_any_chunk(mstate m, mchunkptr p) { |
| 1814 | assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD)); |
| 1815 | assert(ok_address(m, p)); |
| 1816 | } |
| 1817 | |
| 1818 | /* Check properties of top chunk */ |
| 1819 | static void do_check_top_chunk(mstate m, mchunkptr p) { |
| 1820 | msegmentptr sp = segment_holding(m, (char*)p); |
| 1821 | size_t sz = p->head & ~INUSE_BITS; /* third-lowest bit can be set! */ |
| 1822 | assert(sp != 0); |
| 1823 | assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD)); |
| 1824 | assert(ok_address(m, p)); |
| 1825 | assert(sz == m->topsize); |
| 1826 | assert(sz > 0); |
| 1827 | assert(sz == ((sp->base + sp->size) - (char*)p) - TOP_FOOT_SIZE); |
| 1828 | assert(pinuse(p)); |
| 1829 | assert(!pinuse(chunk_plus_offset(p, sz))); |
| 1830 | } |
| 1831 | |
| 1832 | /* Check properties of (inuse) mmapped chunks */ |
| 1833 | static void do_check_mmapped_chunk(mstate m, mchunkptr p) { |
| 1834 | size_t sz = chunksize(p); |
| 1835 | size_t len = (sz + (p->prev_foot) + MMAP_FOOT_PAD); |
| 1836 | assert(is_mmapped(p)); |
| 1837 | assert(use_mmap(m)); |
| 1838 | assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD)); |
| 1839 | assert(ok_address(m, p)); |
| 1840 | assert(!is_small(sz)); |
| 1841 | assert((len & (mparams.page_size-SIZE_T_ONE)) == 0); |
| 1842 | assert(chunk_plus_offset(p, sz)->head == FENCEPOST_HEAD); |
| 1843 | assert(chunk_plus_offset(p, sz+SIZE_T_SIZE)->head == 0); |
| 1844 | } |
| 1845 | |
| 1846 | /* Check properties of inuse chunks */ |
| 1847 | static void do_check_inuse_chunk(mstate m, mchunkptr p) { |
| 1848 | do_check_any_chunk(m, p); |
| 1849 | assert(is_inuse(p)); |
| 1850 | assert(next_pinuse(p)); |
| 1851 | /* If not pinuse and not mmapped, previous chunk has OK offset */ |
| 1852 | assert(is_mmapped(p) || pinuse(p) || next_chunk(prev_chunk(p)) == p); |
| 1853 | if (is_mmapped(p)) |
| 1854 | do_check_mmapped_chunk(m, p); |
| 1855 | } |
| 1856 | |
| 1857 | /* Check properties of free chunks */ |
| 1858 | static void do_check_free_chunk(mstate m, mchunkptr p) { |
| 1859 | size_t sz = chunksize(p); |
| 1860 | mchunkptr next = chunk_plus_offset(p, sz); |
| 1861 | do_check_any_chunk(m, p); |
| 1862 | assert(!is_inuse(p)); |
| 1863 | assert(!next_pinuse(p)); |
| 1864 | assert (!is_mmapped(p)); |
| 1865 | if (p != m->dv && p != m->top) { |
| 1866 | if (sz >= MIN_CHUNK_SIZE) { |
| 1867 | assert((sz & CHUNK_ALIGN_MASK) == 0); |
| 1868 | assert(is_aligned(chunk2mem(p))); |
| 1869 | assert(next->prev_foot == sz); |
| 1870 | assert(pinuse(p)); |
| 1871 | assert (next == m->top || is_inuse(next)); |
| 1872 | assert(p->fd->bk == p); |
| 1873 | assert(p->bk->fd == p); |
| 1874 | } |
| 1875 | else /* markers are always of size SIZE_T_SIZE */ |
| 1876 | assert(sz == SIZE_T_SIZE); |
| 1877 | } |
| 1878 | } |
| 1879 | |
| 1880 | /* Check properties of malloced chunks at the point they are malloced */ |
| 1881 | static void do_check_malloced_chunk(mstate m, void* mem, size_t s) { |
| 1882 | if (mem != 0) { |
| 1883 | mchunkptr p = mem2chunk(mem); |
| 1884 | size_t sz = p->head & ~INUSE_BITS; |
| 1885 | do_check_inuse_chunk(m, p); |
| 1886 | assert((sz & CHUNK_ALIGN_MASK) == 0); |
| 1887 | assert(sz >= MIN_CHUNK_SIZE); |
| 1888 | assert(sz >= s); |
| 1889 | /* unless mmapped, size is less than MIN_CHUNK_SIZE more than request */ |
| 1890 | assert(is_mmapped(p) || sz < (s + MIN_CHUNK_SIZE)); |
| 1891 | } |
| 1892 | } |
| 1893 | |
| 1894 | /* Check a tree and its subtrees. */ |
| 1895 | static void do_check_tree(mstate m, tchunkptr t) { |
| 1896 | tchunkptr head = 0; |
| 1897 | tchunkptr u = t; |
| 1898 | bindex_t tindex = t->index; |
| 1899 | size_t tsize = chunksize(t); |
| 1900 | bindex_t idx; |
| 1901 | compute_tree_index(tsize, idx); |
| 1902 | assert(tindex == idx); |
| 1903 | assert(tsize >= MIN_LARGE_SIZE); |
| 1904 | assert(tsize >= minsize_for_tree_index(idx)); |
| 1905 | assert((idx == NTREEBINS-1) || (tsize < minsize_for_tree_index((idx+1)))); |
| 1906 | |
| 1907 | do { /* traverse through chain of same-sized nodes */ |
| 1908 | do_check_any_chunk(m, ((mchunkptr)u)); |
| 1909 | assert(u->index == tindex); |
| 1910 | assert(chunksize(u) == tsize); |
| 1911 | assert(!is_inuse(u)); |
| 1912 | assert(!next_pinuse(u)); |
| 1913 | assert(u->fd->bk == u); |
| 1914 | assert(u->bk->fd == u); |
| 1915 | if (u->parent == 0) { |
| 1916 | assert(u->child[0] == 0); |
| 1917 | assert(u->child[1] == 0); |
| 1918 | } |
| 1919 | else { |
| 1920 | assert(head == 0); /* only one node on chain has parent */ |
| 1921 | head = u; |
| 1922 | assert(u->parent != u); |
| 1923 | assert (u->parent->child[0] == u || |
| 1924 | u->parent->child[1] == u || |
| 1925 | *((tbinptr*)(u->parent)) == u); |
| 1926 | if (u->child[0] != 0) { |
| 1927 | assert(u->child[0]->parent == u); |
| 1928 | assert(u->child[0] != u); |
| 1929 | do_check_tree(m, u->child[0]); |
| 1930 | } |
| 1931 | if (u->child[1] != 0) { |
| 1932 | assert(u->child[1]->parent == u); |
| 1933 | assert(u->child[1] != u); |
| 1934 | do_check_tree(m, u->child[1]); |
| 1935 | } |
| 1936 | if (u->child[0] != 0 && u->child[1] != 0) { |
| 1937 | assert(chunksize(u->child[0]) < chunksize(u->child[1])); |
| 1938 | } |
| 1939 | } |
| 1940 | u = u->fd; |
| 1941 | } while (u != t); |
| 1942 | assert(head != 0); |
| 1943 | } |
| 1944 | |
| 1945 | /* Check all the chunks in a treebin. */ |
| 1946 | static void do_check_treebin(mstate m, bindex_t i) { |
| 1947 | tbinptr* tb = treebin_at(m, i); |
| 1948 | tchunkptr t = *tb; |
| 1949 | int empty = (m->treemap & (1U << i)) == 0; |
| 1950 | if (t == 0) |
| 1951 | assert(empty); |
| 1952 | if (!empty) |
| 1953 | do_check_tree(m, t); |
| 1954 | } |
| 1955 | |
| 1956 | /* Check all the chunks in a smallbin. */ |
| 1957 | static void do_check_smallbin(mstate m, bindex_t i) { |
| 1958 | sbinptr b = smallbin_at(m, i); |
| 1959 | mchunkptr p = b->bk; |
| 1960 | unsigned int empty = (m->smallmap & (1U << i)) == 0; |
| 1961 | if (p == b) |
| 1962 | assert(empty); |
| 1963 | if (!empty) { |
| 1964 | for (; p != b; p = p->bk) { |
| 1965 | size_t size = chunksize(p); |
| 1966 | mchunkptr q; |
| 1967 | /* each chunk claims to be free */ |
| 1968 | do_check_free_chunk(m, p); |
| 1969 | /* chunk belongs in bin */ |
| 1970 | assert(small_index(size) == i); |
| 1971 | assert(p->bk == b || chunksize(p->bk) == chunksize(p)); |
| 1972 | /* chunk is followed by an inuse chunk */ |
| 1973 | q = next_chunk(p); |
| 1974 | if (q->head != FENCEPOST_HEAD) |
| 1975 | do_check_inuse_chunk(m, q); |
| 1976 | } |
| 1977 | } |
| 1978 | } |
| 1979 | |
| 1980 | /* Find x in a bin. Used in other check functions. */ |
| 1981 | static int bin_find(mstate m, mchunkptr x) { |
| 1982 | size_t size = chunksize(x); |
| 1983 | if (is_small(size)) { |
| 1984 | bindex_t sidx = small_index(size); |
| 1985 | sbinptr b = smallbin_at(m, sidx); |
| 1986 | if (smallmap_is_marked(m, sidx)) { |
| 1987 | mchunkptr p = b; |
| 1988 | do { |
| 1989 | if (p == x) |
| 1990 | return 1; |
| 1991 | } while ((p = p->fd) != b); |
| 1992 | } |
| 1993 | } |
| 1994 | else { |
| 1995 | bindex_t tidx; |
| 1996 | compute_tree_index(size, tidx); |
| 1997 | if (treemap_is_marked(m, tidx)) { |
| 1998 | tchunkptr t = *treebin_at(m, tidx); |
| 1999 | size_t sizebits = size << leftshift_for_tree_index(tidx); |
| 2000 | while (t != 0 && chunksize(t) != size) { |
| 2001 | t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]; |
| 2002 | sizebits <<= 1; |
| 2003 | } |
| 2004 | if (t != 0) { |
| 2005 | tchunkptr u = t; |
| 2006 | do { |
| 2007 | if (u == (tchunkptr)x) |
| 2008 | return 1; |
| 2009 | } while ((u = u->fd) != t); |
| 2010 | } |
| 2011 | } |
| 2012 | } |
| 2013 | return 0; |
| 2014 | } |
| 2015 | |
| 2016 | /* Traverse each chunk and check it; return total */ |
| 2017 | static size_t traverse_and_check(mstate m) { |
| 2018 | size_t sum = 0; |
| 2019 | if (is_initialized(m)) { |
| 2020 | msegmentptr s = &m->seg; |
| 2021 | sum += m->topsize + TOP_FOOT_SIZE; |
| 2022 | while (s != 0) { |
| 2023 | mchunkptr q = align_as_chunk(s->base); |
| 2024 | mchunkptr lastq = 0; |
| 2025 | assert(pinuse(q)); |
| 2026 | while (segment_holds(s, q) && |
| 2027 | q != m->top && q->head != FENCEPOST_HEAD) { |
| 2028 | sum += chunksize(q); |
| 2029 | if (is_inuse(q)) { |
| 2030 | assert(!bin_find(m, q)); |
| 2031 | do_check_inuse_chunk(m, q); |
| 2032 | } |
| 2033 | else { |
| 2034 | assert(q == m->dv || bin_find(m, q)); |
| 2035 | assert(lastq == 0 || is_inuse(lastq)); /* Not 2 consecutive free */ |
| 2036 | do_check_free_chunk(m, q); |
| 2037 | } |
| 2038 | lastq = q; |
| 2039 | q = next_chunk(q); |
| 2040 | } |
| 2041 | s = s->next; |
| 2042 | } |
| 2043 | } |
| 2044 | return sum; |
| 2045 | } |
| 2046 | |
| 2047 | |
| 2048 | /* Check all properties of malloc_state. */ |
| 2049 | static void do_check_malloc_state(mstate m) { |
| 2050 | bindex_t i; |
| 2051 | size_t total; |
| 2052 | /* check bins */ |
| 2053 | for (i = 0; i < NSMALLBINS; ++i) |
| 2054 | do_check_smallbin(m, i); |
| 2055 | for (i = 0; i < NTREEBINS; ++i) |
| 2056 | do_check_treebin(m, i); |
| 2057 | |
| 2058 | if (m->dvsize != 0) { /* check dv chunk */ |
| 2059 | do_check_any_chunk(m, m->dv); |
| 2060 | assert(m->dvsize == chunksize(m->dv)); |
| 2061 | assert(m->dvsize >= MIN_CHUNK_SIZE); |
| 2062 | assert(bin_find(m, m->dv) == 0); |
| 2063 | } |
| 2064 | |
| 2065 | if (m->top != 0) { /* check top chunk */ |
| 2066 | do_check_top_chunk(m, m->top); |
| 2067 | /*assert(m->topsize == chunksize(m->top)); redundant */ |
| 2068 | assert(m->topsize > 0); |
| 2069 | assert(bin_find(m, m->top) == 0); |
| 2070 | } |
| 2071 | |
| 2072 | total = traverse_and_check(m); |
| 2073 | assert(total <= m->footprint); |
| 2074 | assert(m->footprint <= m->max_footprint); |
| 2075 | } |
| 2076 | #endif /* DEBUG */ |
| 2077 | |
| 2078 | /* ----------------------------- statistics ------------------------------ */ |
| 2079 | |
| 2080 | #if !NO_MALLINFO |
Dave Barach | af7dd5b | 2018-08-23 17:08:44 -0400 | [diff] [blame] | 2081 | static struct dlmallinfo internal_mallinfo(mstate m) { |
| 2082 | struct dlmallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 2083 | ensure_initialization(); |
| 2084 | if (!PREACTION(m)) { |
| 2085 | check_malloc_state(m); |
| 2086 | if (is_initialized(m)) { |
| 2087 | size_t nfree = SIZE_T_ONE; /* top always free */ |
| 2088 | size_t mfree = m->topsize + TOP_FOOT_SIZE; |
| 2089 | size_t sum = mfree; |
| 2090 | msegmentptr s = &m->seg; |
| 2091 | while (s != 0) { |
| 2092 | mchunkptr q = align_as_chunk(s->base); |
| 2093 | while (segment_holds(s, q) && |
| 2094 | q != m->top && q->head != FENCEPOST_HEAD) { |
| 2095 | size_t sz = chunksize(q); |
| 2096 | sum += sz; |
| 2097 | if (!is_inuse(q)) { |
| 2098 | mfree += sz; |
| 2099 | ++nfree; |
| 2100 | } |
| 2101 | q = next_chunk(q); |
| 2102 | } |
| 2103 | s = s->next; |
| 2104 | } |
| 2105 | |
| 2106 | nm.arena = sum; |
| 2107 | nm.ordblks = nfree; |
| 2108 | nm.hblkhd = m->footprint - sum; |
| 2109 | nm.usmblks = m->max_footprint; |
| 2110 | nm.uordblks = m->footprint - mfree; |
| 2111 | nm.fordblks = mfree; |
| 2112 | nm.keepcost = m->topsize; |
| 2113 | } |
| 2114 | |
| 2115 | POSTACTION(m); |
| 2116 | } |
| 2117 | return nm; |
| 2118 | } |
| 2119 | #endif /* !NO_MALLINFO */ |
| 2120 | |
| 2121 | #if !NO_MALLOC_STATS |
| 2122 | static void internal_malloc_stats(mstate m) { |
| 2123 | ensure_initialization(); |
| 2124 | if (!PREACTION(m)) { |
| 2125 | size_t maxfp = 0; |
| 2126 | size_t fp = 0; |
| 2127 | size_t used = 0; |
| 2128 | check_malloc_state(m); |
| 2129 | if (is_initialized(m)) { |
| 2130 | msegmentptr s = &m->seg; |
| 2131 | maxfp = m->max_footprint; |
| 2132 | fp = m->footprint; |
| 2133 | used = fp - (m->topsize + TOP_FOOT_SIZE); |
| 2134 | |
| 2135 | while (s != 0) { |
| 2136 | mchunkptr q = align_as_chunk(s->base); |
| 2137 | while (segment_holds(s, q) && |
| 2138 | q != m->top && q->head != FENCEPOST_HEAD) { |
| 2139 | if (!is_inuse(q)) |
| 2140 | used -= chunksize(q); |
| 2141 | q = next_chunk(q); |
| 2142 | } |
| 2143 | s = s->next; |
| 2144 | } |
| 2145 | } |
| 2146 | POSTACTION(m); /* drop lock */ |
| 2147 | fprintf(stderr, "max system bytes = %10lu\n", (unsigned long)(maxfp)); |
| 2148 | fprintf(stderr, "system bytes = %10lu\n", (unsigned long)(fp)); |
| 2149 | fprintf(stderr, "in use bytes = %10lu\n", (unsigned long)(used)); |
| 2150 | } |
| 2151 | } |
| 2152 | #endif /* NO_MALLOC_STATS */ |
| 2153 | |
| 2154 | /* ----------------------- Operations on smallbins ----------------------- */ |
| 2155 | |
| 2156 | /* |
| 2157 | Various forms of linking and unlinking are defined as macros. Even |
| 2158 | the ones for trees, which are very long but have very short typical |
| 2159 | paths. This is ugly but reduces reliance on inlining support of |
| 2160 | compilers. |
| 2161 | */ |
| 2162 | |
| 2163 | /* Link a free chunk into a smallbin */ |
| 2164 | #define insert_small_chunk(M, P, S) {\ |
| 2165 | bindex_t I = small_index(S);\ |
| 2166 | mchunkptr B = smallbin_at(M, I);\ |
| 2167 | mchunkptr F = B;\ |
| 2168 | assert(S >= MIN_CHUNK_SIZE);\ |
| 2169 | if (!smallmap_is_marked(M, I))\ |
| 2170 | mark_smallmap(M, I);\ |
| 2171 | else if (RTCHECK(ok_address(M, B->fd)))\ |
| 2172 | F = B->fd;\ |
| 2173 | else {\ |
| 2174 | CORRUPTION_ERROR_ACTION(M);\ |
| 2175 | }\ |
| 2176 | B->fd = P;\ |
| 2177 | F->bk = P;\ |
| 2178 | P->fd = F;\ |
| 2179 | P->bk = B;\ |
| 2180 | } |
| 2181 | |
| 2182 | /* Unlink a chunk from a smallbin */ |
| 2183 | #define unlink_small_chunk(M, P, S) {\ |
| 2184 | mchunkptr F = P->fd;\ |
| 2185 | mchunkptr B = P->bk;\ |
| 2186 | bindex_t I = small_index(S);\ |
| 2187 | assert(P != B);\ |
| 2188 | assert(P != F);\ |
| 2189 | assert(chunksize(P) == small_index2size(I));\ |
| 2190 | if (RTCHECK(F == smallbin_at(M,I) || (ok_address(M, F) && F->bk == P))) { \ |
| 2191 | if (B == F) {\ |
| 2192 | clear_smallmap(M, I);\ |
| 2193 | }\ |
| 2194 | else if (RTCHECK(B == smallbin_at(M,I) ||\ |
| 2195 | (ok_address(M, B) && B->fd == P))) {\ |
| 2196 | F->bk = B;\ |
| 2197 | B->fd = F;\ |
| 2198 | }\ |
| 2199 | else {\ |
| 2200 | CORRUPTION_ERROR_ACTION(M);\ |
| 2201 | }\ |
| 2202 | }\ |
| 2203 | else {\ |
| 2204 | CORRUPTION_ERROR_ACTION(M);\ |
| 2205 | }\ |
| 2206 | } |
| 2207 | |
| 2208 | /* Unlink the first chunk from a smallbin */ |
| 2209 | #define unlink_first_small_chunk(M, B, P, I) {\ |
| 2210 | mchunkptr F = P->fd;\ |
| 2211 | assert(P != B);\ |
| 2212 | assert(P != F);\ |
| 2213 | assert(chunksize(P) == small_index2size(I));\ |
| 2214 | if (B == F) {\ |
| 2215 | clear_smallmap(M, I);\ |
| 2216 | }\ |
| 2217 | else if (RTCHECK(ok_address(M, F) && F->bk == P)) {\ |
| 2218 | F->bk = B;\ |
| 2219 | B->fd = F;\ |
| 2220 | }\ |
| 2221 | else {\ |
| 2222 | CORRUPTION_ERROR_ACTION(M);\ |
| 2223 | }\ |
| 2224 | } |
| 2225 | |
| 2226 | /* Replace dv node, binning the old one */ |
| 2227 | /* Used only when dvsize known to be small */ |
| 2228 | #define replace_dv(M, P, S) {\ |
| 2229 | size_t DVS = M->dvsize;\ |
| 2230 | assert(is_small(DVS));\ |
| 2231 | if (DVS != 0) {\ |
| 2232 | mchunkptr DV = M->dv;\ |
| 2233 | insert_small_chunk(M, DV, DVS);\ |
| 2234 | }\ |
| 2235 | M->dvsize = S;\ |
| 2236 | M->dv = P;\ |
| 2237 | } |
| 2238 | |
| 2239 | /* ------------------------- Operations on trees ------------------------- */ |
| 2240 | |
| 2241 | /* Insert chunk into tree */ |
| 2242 | #define insert_large_chunk(M, X, S) {\ |
| 2243 | tbinptr* H;\ |
| 2244 | bindex_t I;\ |
| 2245 | compute_tree_index(S, I);\ |
| 2246 | H = treebin_at(M, I);\ |
| 2247 | X->index = I;\ |
| 2248 | X->child[0] = X->child[1] = 0;\ |
| 2249 | if (!treemap_is_marked(M, I)) {\ |
| 2250 | mark_treemap(M, I);\ |
| 2251 | *H = X;\ |
| 2252 | X->parent = (tchunkptr)H;\ |
| 2253 | X->fd = X->bk = X;\ |
| 2254 | }\ |
| 2255 | else {\ |
| 2256 | tchunkptr T = *H;\ |
| 2257 | size_t K = S << leftshift_for_tree_index(I);\ |
| 2258 | for (;;) {\ |
| 2259 | if (chunksize(T) != S) {\ |
| 2260 | tchunkptr* C = &(T->child[(K >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]);\ |
| 2261 | K <<= 1;\ |
| 2262 | if (*C != 0)\ |
| 2263 | T = *C;\ |
| 2264 | else if (RTCHECK(ok_address(M, C))) {\ |
| 2265 | *C = X;\ |
| 2266 | X->parent = T;\ |
| 2267 | X->fd = X->bk = X;\ |
| 2268 | break;\ |
| 2269 | }\ |
| 2270 | else {\ |
| 2271 | CORRUPTION_ERROR_ACTION(M);\ |
| 2272 | break;\ |
| 2273 | }\ |
| 2274 | }\ |
| 2275 | else {\ |
| 2276 | tchunkptr F = T->fd;\ |
| 2277 | if (RTCHECK(ok_address(M, T) && ok_address(M, F))) {\ |
| 2278 | T->fd = F->bk = X;\ |
| 2279 | X->fd = F;\ |
| 2280 | X->bk = T;\ |
| 2281 | X->parent = 0;\ |
| 2282 | break;\ |
| 2283 | }\ |
| 2284 | else {\ |
| 2285 | CORRUPTION_ERROR_ACTION(M);\ |
| 2286 | break;\ |
| 2287 | }\ |
| 2288 | }\ |
| 2289 | }\ |
| 2290 | }\ |
| 2291 | } |
| 2292 | |
| 2293 | /* |
| 2294 | Unlink steps: |
| 2295 | |
| 2296 | 1. If x is a chained node, unlink it from its same-sized fd/bk links |
| 2297 | and choose its bk node as its replacement. |
| 2298 | 2. If x was the last node of its size, but not a leaf node, it must |
| 2299 | be replaced with a leaf node (not merely one with an open left or |
| 2300 | right), to make sure that lefts and rights of descendents |
| 2301 | correspond properly to bit masks. We use the rightmost descendent |
| 2302 | of x. We could use any other leaf, but this is easy to locate and |
| 2303 | tends to counteract removal of leftmosts elsewhere, and so keeps |
| 2304 | paths shorter than minimally guaranteed. This doesn't loop much |
| 2305 | because on average a node in a tree is near the bottom. |
| 2306 | 3. If x is the base of a chain (i.e., has parent links) relink |
| 2307 | x's parent and children to x's replacement (or null if none). |
| 2308 | */ |
| 2309 | |
| 2310 | #define unlink_large_chunk(M, X) {\ |
| 2311 | tchunkptr XP = X->parent;\ |
| 2312 | tchunkptr R;\ |
| 2313 | if (X->bk != X) {\ |
| 2314 | tchunkptr F = X->fd;\ |
| 2315 | R = X->bk;\ |
| 2316 | if (RTCHECK(ok_address(M, F) && F->bk == X && R->fd == X)) {\ |
| 2317 | F->bk = R;\ |
| 2318 | R->fd = F;\ |
| 2319 | }\ |
| 2320 | else {\ |
| 2321 | CORRUPTION_ERROR_ACTION(M);\ |
| 2322 | }\ |
| 2323 | }\ |
| 2324 | else {\ |
| 2325 | tchunkptr* RP;\ |
| 2326 | if (((R = *(RP = &(X->child[1]))) != 0) ||\ |
| 2327 | ((R = *(RP = &(X->child[0]))) != 0)) {\ |
| 2328 | tchunkptr* CP;\ |
| 2329 | while ((*(CP = &(R->child[1])) != 0) ||\ |
| 2330 | (*(CP = &(R->child[0])) != 0)) {\ |
| 2331 | R = *(RP = CP);\ |
| 2332 | }\ |
| 2333 | if (RTCHECK(ok_address(M, RP)))\ |
| 2334 | *RP = 0;\ |
| 2335 | else {\ |
| 2336 | CORRUPTION_ERROR_ACTION(M);\ |
| 2337 | }\ |
| 2338 | }\ |
| 2339 | }\ |
| 2340 | if (XP != 0) {\ |
| 2341 | tbinptr* H = treebin_at(M, X->index);\ |
| 2342 | if (X == *H) {\ |
| 2343 | if ((*H = R) == 0) \ |
| 2344 | clear_treemap(M, X->index);\ |
| 2345 | }\ |
| 2346 | else if (RTCHECK(ok_address(M, XP))) {\ |
| 2347 | if (XP->child[0] == X) \ |
| 2348 | XP->child[0] = R;\ |
| 2349 | else \ |
| 2350 | XP->child[1] = R;\ |
| 2351 | }\ |
| 2352 | else\ |
| 2353 | CORRUPTION_ERROR_ACTION(M);\ |
| 2354 | if (R != 0) {\ |
| 2355 | if (RTCHECK(ok_address(M, R))) {\ |
| 2356 | tchunkptr C0, C1;\ |
| 2357 | R->parent = XP;\ |
| 2358 | if ((C0 = X->child[0]) != 0) {\ |
| 2359 | if (RTCHECK(ok_address(M, C0))) {\ |
| 2360 | R->child[0] = C0;\ |
| 2361 | C0->parent = R;\ |
| 2362 | }\ |
| 2363 | else\ |
| 2364 | CORRUPTION_ERROR_ACTION(M);\ |
| 2365 | }\ |
| 2366 | if ((C1 = X->child[1]) != 0) {\ |
| 2367 | if (RTCHECK(ok_address(M, C1))) {\ |
| 2368 | R->child[1] = C1;\ |
| 2369 | C1->parent = R;\ |
| 2370 | }\ |
| 2371 | else\ |
| 2372 | CORRUPTION_ERROR_ACTION(M);\ |
| 2373 | }\ |
| 2374 | }\ |
| 2375 | else\ |
| 2376 | CORRUPTION_ERROR_ACTION(M);\ |
| 2377 | }\ |
| 2378 | }\ |
| 2379 | } |
| 2380 | |
| 2381 | /* Relays to large vs small bin operations */ |
| 2382 | |
| 2383 | #define insert_chunk(M, P, S)\ |
| 2384 | if (is_small(S)) insert_small_chunk(M, P, S)\ |
| 2385 | else { tchunkptr TP = (tchunkptr)(P); insert_large_chunk(M, TP, S); } |
| 2386 | |
| 2387 | #define unlink_chunk(M, P, S)\ |
| 2388 | if (is_small(S)) unlink_small_chunk(M, P, S)\ |
| 2389 | else { tchunkptr TP = (tchunkptr)(P); unlink_large_chunk(M, TP); } |
| 2390 | |
| 2391 | |
| 2392 | /* Relays to internal calls to malloc/free from realloc, memalign etc */ |
| 2393 | |
| 2394 | #if ONLY_MSPACES |
| 2395 | #define internal_malloc(m, b) mspace_malloc(m, b) |
| 2396 | #define internal_free(m, mem) mspace_free(m,mem); |
| 2397 | #else /* ONLY_MSPACES */ |
| 2398 | #if MSPACES |
| 2399 | #define internal_malloc(m, b)\ |
| 2400 | ((m == gm)? dlmalloc(b) : mspace_malloc(m, b)) |
| 2401 | #define internal_free(m, mem)\ |
| 2402 | if (m == gm) dlfree(mem); else mspace_free(m,mem); |
| 2403 | #else /* MSPACES */ |
| 2404 | #define internal_malloc(m, b) dlmalloc(b) |
| 2405 | #define internal_free(m, mem) dlfree(mem) |
| 2406 | #endif /* MSPACES */ |
| 2407 | #endif /* ONLY_MSPACES */ |
| 2408 | |
| 2409 | /* ----------------------- Direct-mmapping chunks ----------------------- */ |
| 2410 | |
| 2411 | /* |
| 2412 | Directly mmapped chunks are set up with an offset to the start of |
| 2413 | the mmapped region stored in the prev_foot field of the chunk. This |
| 2414 | allows reconstruction of the required argument to MUNMAP when freed, |
| 2415 | and also allows adjustment of the returned chunk to meet alignment |
| 2416 | requirements (especially in memalign). |
| 2417 | */ |
| 2418 | |
| 2419 | /* Malloc using mmap */ |
| 2420 | static void* mmap_alloc(mstate m, size_t nb) { |
| 2421 | size_t mmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK); |
| 2422 | if (m->footprint_limit != 0) { |
| 2423 | size_t fp = m->footprint + mmsize; |
| 2424 | if (fp <= m->footprint || fp > m->footprint_limit) |
| 2425 | return 0; |
| 2426 | } |
| 2427 | if (mmsize > nb) { /* Check for wrap around 0 */ |
| 2428 | char* mm = (char*)(CALL_DIRECT_MMAP(mmsize)); |
| 2429 | if (mm != CMFAIL) { |
| 2430 | size_t offset = align_offset(chunk2mem(mm)); |
| 2431 | size_t psize = mmsize - offset - MMAP_FOOT_PAD; |
| 2432 | mchunkptr p = (mchunkptr)(mm + offset); |
| 2433 | p->prev_foot = offset; |
| 2434 | p->head = psize; |
| 2435 | mark_inuse_foot(m, p, psize); |
| 2436 | chunk_plus_offset(p, psize)->head = FENCEPOST_HEAD; |
| 2437 | chunk_plus_offset(p, psize+SIZE_T_SIZE)->head = 0; |
| 2438 | |
| 2439 | if (m->least_addr == 0 || mm < m->least_addr) |
| 2440 | m->least_addr = mm; |
| 2441 | if ((m->footprint += mmsize) > m->max_footprint) |
| 2442 | m->max_footprint = m->footprint; |
| 2443 | assert(is_aligned(chunk2mem(p))); |
| 2444 | check_mmapped_chunk(m, p); |
| 2445 | return chunk2mem(p); |
| 2446 | } |
| 2447 | } |
| 2448 | return 0; |
| 2449 | } |
| 2450 | |
| 2451 | /* Realloc using mmap */ |
| 2452 | static mchunkptr mmap_resize(mstate m, mchunkptr oldp, size_t nb, int flags) { |
| 2453 | size_t oldsize = chunksize(oldp); |
| 2454 | (void)flags; /* placate people compiling -Wunused */ |
| 2455 | if (is_small(nb)) /* Can't shrink mmap regions below small size */ |
| 2456 | return 0; |
| 2457 | /* Keep old chunk if big enough but not too big */ |
| 2458 | if (oldsize >= nb + SIZE_T_SIZE && |
| 2459 | (oldsize - nb) <= (mparams.granularity << 1)) |
| 2460 | return oldp; |
| 2461 | else { |
| 2462 | size_t offset = oldp->prev_foot; |
| 2463 | size_t oldmmsize = oldsize + offset + MMAP_FOOT_PAD; |
| 2464 | size_t newmmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK); |
| 2465 | char* cp = (char*)CALL_MREMAP((char*)oldp - offset, |
| 2466 | oldmmsize, newmmsize, flags); |
| 2467 | if (cp != CMFAIL) { |
| 2468 | mchunkptr newp = (mchunkptr)(cp + offset); |
| 2469 | size_t psize = newmmsize - offset - MMAP_FOOT_PAD; |
| 2470 | newp->head = psize; |
| 2471 | mark_inuse_foot(m, newp, psize); |
| 2472 | chunk_plus_offset(newp, psize)->head = FENCEPOST_HEAD; |
| 2473 | chunk_plus_offset(newp, psize+SIZE_T_SIZE)->head = 0; |
| 2474 | |
| 2475 | if (cp < m->least_addr) |
| 2476 | m->least_addr = cp; |
| 2477 | if ((m->footprint += newmmsize - oldmmsize) > m->max_footprint) |
| 2478 | m->max_footprint = m->footprint; |
| 2479 | check_mmapped_chunk(m, newp); |
| 2480 | return newp; |
| 2481 | } |
| 2482 | } |
| 2483 | return 0; |
| 2484 | } |
| 2485 | |
| 2486 | |
| 2487 | /* -------------------------- mspace management -------------------------- */ |
| 2488 | |
| 2489 | /* Initialize top chunk and its size */ |
| 2490 | static void init_top(mstate m, mchunkptr p, size_t psize) { |
| 2491 | /* Ensure alignment */ |
| 2492 | size_t offset = align_offset(chunk2mem(p)); |
| 2493 | p = (mchunkptr)((char*)p + offset); |
| 2494 | psize -= offset; |
| 2495 | |
| 2496 | m->top = p; |
| 2497 | m->topsize = psize; |
| 2498 | p->head = psize | PINUSE_BIT; |
| 2499 | /* set size of fake trailing chunk holding overhead space only once */ |
| 2500 | chunk_plus_offset(p, psize)->head = TOP_FOOT_SIZE; |
| 2501 | m->trim_check = mparams.trim_threshold; /* reset on each update */ |
| 2502 | } |
| 2503 | |
| 2504 | /* Initialize bins for a new mstate that is otherwise zeroed out */ |
| 2505 | static void init_bins(mstate m) { |
| 2506 | /* Establish circular links for smallbins */ |
| 2507 | bindex_t i; |
| 2508 | for (i = 0; i < NSMALLBINS; ++i) { |
| 2509 | sbinptr bin = smallbin_at(m,i); |
| 2510 | bin->fd = bin->bk = bin; |
| 2511 | } |
| 2512 | } |
| 2513 | |
| 2514 | #if PROCEED_ON_ERROR |
| 2515 | |
| 2516 | /* default corruption action */ |
| 2517 | static void reset_on_error(mstate m) { |
| 2518 | int i; |
| 2519 | ++malloc_corruption_error_count; |
| 2520 | /* Reinitialize fields to forget about all memory */ |
| 2521 | m->smallmap = m->treemap = 0; |
| 2522 | m->dvsize = m->topsize = 0; |
| 2523 | m->seg.base = 0; |
| 2524 | m->seg.size = 0; |
| 2525 | m->seg.next = 0; |
| 2526 | m->top = m->dv = 0; |
| 2527 | for (i = 0; i < NTREEBINS; ++i) |
| 2528 | *treebin_at(m, i) = 0; |
| 2529 | init_bins(m); |
| 2530 | } |
| 2531 | #endif /* PROCEED_ON_ERROR */ |
| 2532 | |
| 2533 | /* Allocate chunk and prepend remainder with chunk in successor base. */ |
| 2534 | static void* prepend_alloc(mstate m, char* newbase, char* oldbase, |
| 2535 | size_t nb) { |
| 2536 | mchunkptr p = align_as_chunk(newbase); |
| 2537 | mchunkptr oldfirst = align_as_chunk(oldbase); |
| 2538 | size_t psize = (char*)oldfirst - (char*)p; |
| 2539 | mchunkptr q = chunk_plus_offset(p, nb); |
| 2540 | size_t qsize = psize - nb; |
| 2541 | set_size_and_pinuse_of_inuse_chunk(m, p, nb); |
| 2542 | |
| 2543 | assert((char*)oldfirst > (char*)q); |
| 2544 | assert(pinuse(oldfirst)); |
| 2545 | assert(qsize >= MIN_CHUNK_SIZE); |
| 2546 | |
| 2547 | /* consolidate remainder with first chunk of old base */ |
| 2548 | if (oldfirst == m->top) { |
| 2549 | size_t tsize = m->topsize += qsize; |
| 2550 | m->top = q; |
| 2551 | q->head = tsize | PINUSE_BIT; |
| 2552 | check_top_chunk(m, q); |
| 2553 | } |
| 2554 | else if (oldfirst == m->dv) { |
| 2555 | size_t dsize = m->dvsize += qsize; |
| 2556 | m->dv = q; |
| 2557 | set_size_and_pinuse_of_free_chunk(q, dsize); |
| 2558 | } |
| 2559 | else { |
| 2560 | if (!is_inuse(oldfirst)) { |
| 2561 | size_t nsize = chunksize(oldfirst); |
| 2562 | unlink_chunk(m, oldfirst, nsize); |
| 2563 | oldfirst = chunk_plus_offset(oldfirst, nsize); |
| 2564 | qsize += nsize; |
| 2565 | } |
| 2566 | set_free_with_pinuse(q, qsize, oldfirst); |
| 2567 | insert_chunk(m, q, qsize); |
| 2568 | check_free_chunk(m, q); |
| 2569 | } |
| 2570 | |
| 2571 | check_malloced_chunk(m, chunk2mem(p), nb); |
| 2572 | return chunk2mem(p); |
| 2573 | } |
| 2574 | |
| 2575 | /* Add a segment to hold a new noncontiguous region */ |
| 2576 | static void add_segment(mstate m, char* tbase, size_t tsize, flag_t mmapped) { |
| 2577 | /* Determine locations and sizes of segment, fenceposts, old top */ |
| 2578 | char* old_top = (char*)m->top; |
| 2579 | msegmentptr oldsp = segment_holding(m, old_top); |
| 2580 | char* old_end = oldsp->base + oldsp->size; |
| 2581 | size_t ssize = pad_request(sizeof(struct malloc_segment)); |
| 2582 | char* rawsp = old_end - (ssize + FOUR_SIZE_T_SIZES + CHUNK_ALIGN_MASK); |
| 2583 | size_t offset = align_offset(chunk2mem(rawsp)); |
| 2584 | char* asp = rawsp + offset; |
| 2585 | char* csp = (asp < (old_top + MIN_CHUNK_SIZE))? old_top : asp; |
| 2586 | mchunkptr sp = (mchunkptr)csp; |
| 2587 | msegmentptr ss = (msegmentptr)(chunk2mem(sp)); |
| 2588 | mchunkptr tnext = chunk_plus_offset(sp, ssize); |
| 2589 | mchunkptr p = tnext; |
| 2590 | int nfences = 0; |
| 2591 | |
| 2592 | /* reset top to new space */ |
| 2593 | init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE); |
| 2594 | |
| 2595 | /* Set up segment record */ |
| 2596 | assert(is_aligned(ss)); |
| 2597 | set_size_and_pinuse_of_inuse_chunk(m, sp, ssize); |
| 2598 | *ss = m->seg; /* Push current record */ |
| 2599 | m->seg.base = tbase; |
| 2600 | m->seg.size = tsize; |
| 2601 | m->seg.sflags = mmapped; |
| 2602 | m->seg.next = ss; |
| 2603 | |
| 2604 | /* Insert trailing fenceposts */ |
| 2605 | for (;;) { |
| 2606 | mchunkptr nextp = chunk_plus_offset(p, SIZE_T_SIZE); |
| 2607 | p->head = FENCEPOST_HEAD; |
| 2608 | ++nfences; |
| 2609 | if ((char*)(&(nextp->head)) < old_end) |
| 2610 | p = nextp; |
| 2611 | else |
| 2612 | break; |
| 2613 | } |
| 2614 | assert(nfences >= 2); |
| 2615 | |
| 2616 | /* Insert the rest of old top into a bin as an ordinary free chunk */ |
| 2617 | if (csp != old_top) { |
| 2618 | mchunkptr q = (mchunkptr)old_top; |
| 2619 | size_t psize = csp - old_top; |
| 2620 | mchunkptr tn = chunk_plus_offset(q, psize); |
| 2621 | set_free_with_pinuse(q, psize, tn); |
| 2622 | insert_chunk(m, q, psize); |
| 2623 | } |
| 2624 | |
| 2625 | check_top_chunk(m, m->top); |
| 2626 | } |
| 2627 | |
| 2628 | /* -------------------------- System allocation -------------------------- */ |
| 2629 | |
| 2630 | /* Get memory from system using MORECORE or MMAP */ |
| 2631 | static void* sys_alloc(mstate m, size_t nb) { |
| 2632 | char* tbase = CMFAIL; |
| 2633 | size_t tsize = 0; |
| 2634 | flag_t mmap_flag = 0; |
| 2635 | size_t asize; /* allocation size */ |
| 2636 | |
| 2637 | ensure_initialization(); |
| 2638 | |
| 2639 | if (use_noexpand(m)) |
| 2640 | return 0; |
| 2641 | |
| 2642 | /* Directly map large chunks, but only if already initialized */ |
| 2643 | if (use_mmap(m) && nb >= mparams.mmap_threshold && m->topsize != 0) { |
| 2644 | void* mem = mmap_alloc(m, nb); |
| 2645 | if (mem != 0) |
| 2646 | return mem; |
| 2647 | } |
| 2648 | |
| 2649 | asize = granularity_align(nb + SYS_ALLOC_PADDING); |
| 2650 | if (asize <= nb) |
| 2651 | return 0; /* wraparound */ |
| 2652 | if (m->footprint_limit != 0) { |
| 2653 | size_t fp = m->footprint + asize; |
| 2654 | if (fp <= m->footprint || fp > m->footprint_limit) |
| 2655 | return 0; |
| 2656 | } |
| 2657 | |
| 2658 | /* |
| 2659 | Try getting memory in any of three ways (in most-preferred to |
| 2660 | least-preferred order): |
| 2661 | 1. A call to MORECORE that can normally contiguously extend memory. |
| 2662 | (disabled if not MORECORE_CONTIGUOUS or not HAVE_MORECORE or |
| 2663 | or main space is mmapped or a previous contiguous call failed) |
| 2664 | 2. A call to MMAP new space (disabled if not HAVE_MMAP). |
| 2665 | Note that under the default settings, if MORECORE is unable to |
| 2666 | fulfill a request, and HAVE_MMAP is true, then mmap is |
| 2667 | used as a noncontiguous system allocator. This is a useful backup |
| 2668 | strategy for systems with holes in address spaces -- in this case |
| 2669 | sbrk cannot contiguously expand the heap, but mmap may be able to |
| 2670 | find space. |
| 2671 | 3. A call to MORECORE that cannot usually contiguously extend memory. |
| 2672 | (disabled if not HAVE_MORECORE) |
| 2673 | |
| 2674 | In all cases, we need to request enough bytes from system to ensure |
| 2675 | we can malloc nb bytes upon success, so pad with enough space for |
| 2676 | top_foot, plus alignment-pad to make sure we don't lose bytes if |
| 2677 | not on boundary, and round this up to a granularity unit. |
| 2678 | */ |
| 2679 | |
| 2680 | if (MORECORE_CONTIGUOUS && !use_noncontiguous(m)) { |
| 2681 | char* br = CMFAIL; |
| 2682 | size_t ssize = asize; /* sbrk call size */ |
| 2683 | msegmentptr ss = (m->top == 0)? 0 : segment_holding(m, (char*)m->top); |
| 2684 | ACQUIRE_MALLOC_GLOBAL_LOCK(); |
| 2685 | |
| 2686 | if (ss == 0) { /* First time through or recovery */ |
| 2687 | char* base = (char*)CALL_MORECORE(0); |
| 2688 | if (base != CMFAIL) { |
| 2689 | size_t fp; |
| 2690 | /* Adjust to end on a page boundary */ |
| 2691 | if (!is_page_aligned(base)) |
| 2692 | ssize += (page_align((size_t)base) - (size_t)base); |
| 2693 | fp = m->footprint + ssize; /* recheck limits */ |
| 2694 | if (ssize > nb && ssize < HALF_MAX_SIZE_T && |
| 2695 | (m->footprint_limit == 0 || |
| 2696 | (fp > m->footprint && fp <= m->footprint_limit)) && |
| 2697 | (br = (char*)(CALL_MORECORE(ssize))) == base) { |
| 2698 | tbase = base; |
| 2699 | tsize = ssize; |
| 2700 | } |
| 2701 | } |
| 2702 | } |
| 2703 | else { |
| 2704 | /* Subtract out existing available top space from MORECORE request. */ |
| 2705 | ssize = granularity_align(nb - m->topsize + SYS_ALLOC_PADDING); |
| 2706 | /* Use mem here only if it did continuously extend old space */ |
| 2707 | if (ssize < HALF_MAX_SIZE_T && |
| 2708 | (br = (char*)(CALL_MORECORE(ssize))) == ss->base+ss->size) { |
| 2709 | tbase = br; |
| 2710 | tsize = ssize; |
| 2711 | } |
| 2712 | } |
| 2713 | |
| 2714 | if (tbase == CMFAIL) { /* Cope with partial failure */ |
| 2715 | if (br != CMFAIL) { /* Try to use/extend the space we did get */ |
| 2716 | if (ssize < HALF_MAX_SIZE_T && |
| 2717 | ssize < nb + SYS_ALLOC_PADDING) { |
| 2718 | size_t esize = granularity_align(nb + SYS_ALLOC_PADDING - ssize); |
| 2719 | if (esize < HALF_MAX_SIZE_T) { |
| 2720 | char* end = (char*)CALL_MORECORE(esize); |
| 2721 | if (end != CMFAIL) |
| 2722 | ssize += esize; |
| 2723 | else { /* Can't use; try to release */ |
| 2724 | (void) CALL_MORECORE(-ssize); |
| 2725 | br = CMFAIL; |
| 2726 | } |
| 2727 | } |
| 2728 | } |
| 2729 | } |
| 2730 | if (br != CMFAIL) { /* Use the space we did get */ |
| 2731 | tbase = br; |
| 2732 | tsize = ssize; |
| 2733 | } |
| 2734 | else |
| 2735 | disable_contiguous(m); /* Don't try contiguous path in the future */ |
| 2736 | } |
| 2737 | |
| 2738 | RELEASE_MALLOC_GLOBAL_LOCK(); |
| 2739 | } |
| 2740 | |
| 2741 | if (HAVE_MMAP && tbase == CMFAIL) { /* Try MMAP */ |
| 2742 | char* mp = (char*)(CALL_MMAP(asize)); |
| 2743 | if (mp != CMFAIL) { |
| 2744 | tbase = mp; |
| 2745 | tsize = asize; |
| 2746 | mmap_flag = USE_MMAP_BIT; |
| 2747 | } |
| 2748 | } |
| 2749 | |
| 2750 | if (HAVE_MORECORE && tbase == CMFAIL) { /* Try noncontiguous MORECORE */ |
| 2751 | if (asize < HALF_MAX_SIZE_T) { |
| 2752 | char* br = CMFAIL; |
| 2753 | char* end = CMFAIL; |
| 2754 | ACQUIRE_MALLOC_GLOBAL_LOCK(); |
| 2755 | br = (char*)(CALL_MORECORE(asize)); |
| 2756 | end = (char*)(CALL_MORECORE(0)); |
| 2757 | RELEASE_MALLOC_GLOBAL_LOCK(); |
| 2758 | if (br != CMFAIL && end != CMFAIL && br < end) { |
| 2759 | size_t ssize = end - br; |
| 2760 | if (ssize > nb + TOP_FOOT_SIZE) { |
| 2761 | tbase = br; |
| 2762 | tsize = ssize; |
| 2763 | } |
| 2764 | } |
| 2765 | } |
| 2766 | } |
| 2767 | |
| 2768 | if (tbase != CMFAIL) { |
| 2769 | |
| 2770 | if ((m->footprint += tsize) > m->max_footprint) |
| 2771 | m->max_footprint = m->footprint; |
| 2772 | |
| 2773 | if (!is_initialized(m)) { /* first-time initialization */ |
| 2774 | if (m->least_addr == 0 || tbase < m->least_addr) |
| 2775 | m->least_addr = tbase; |
| 2776 | m->seg.base = tbase; |
| 2777 | m->seg.size = tsize; |
| 2778 | m->seg.sflags = mmap_flag; |
| 2779 | m->magic = mparams.magic; |
| 2780 | m->release_checks = MAX_RELEASE_CHECK_RATE; |
| 2781 | init_bins(m); |
| 2782 | #if !ONLY_MSPACES |
| 2783 | if (is_global(m)) |
| 2784 | init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE); |
| 2785 | else |
| 2786 | #endif |
| 2787 | { |
| 2788 | /* Offset top by embedded malloc_state */ |
| 2789 | mchunkptr mn = next_chunk(mem2chunk(m)); |
| 2790 | init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) -TOP_FOOT_SIZE); |
| 2791 | } |
| 2792 | } |
| 2793 | |
| 2794 | else { |
| 2795 | /* Try to merge with an existing segment */ |
| 2796 | msegmentptr sp = &m->seg; |
| 2797 | /* Only consider most recent segment if traversal suppressed */ |
| 2798 | while (sp != 0 && tbase != sp->base + sp->size) |
| 2799 | sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next; |
| 2800 | if (sp != 0 && |
| 2801 | !is_extern_segment(sp) && |
| 2802 | (sp->sflags & USE_MMAP_BIT) == mmap_flag && |
| 2803 | segment_holds(sp, m->top)) { /* append */ |
| 2804 | sp->size += tsize; |
| 2805 | init_top(m, m->top, m->topsize + tsize); |
| 2806 | } |
| 2807 | else { |
| 2808 | if (tbase < m->least_addr) |
| 2809 | m->least_addr = tbase; |
| 2810 | sp = &m->seg; |
| 2811 | while (sp != 0 && sp->base != tbase + tsize) |
| 2812 | sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next; |
| 2813 | if (sp != 0 && |
| 2814 | !is_extern_segment(sp) && |
| 2815 | (sp->sflags & USE_MMAP_BIT) == mmap_flag) { |
| 2816 | char* oldbase = sp->base; |
| 2817 | sp->base = tbase; |
| 2818 | sp->size += tsize; |
| 2819 | return prepend_alloc(m, tbase, oldbase, nb); |
| 2820 | } |
| 2821 | else |
| 2822 | add_segment(m, tbase, tsize, mmap_flag); |
| 2823 | } |
| 2824 | } |
| 2825 | |
| 2826 | if (nb < m->topsize) { /* Allocate from new or extended top space */ |
| 2827 | size_t rsize = m->topsize -= nb; |
| 2828 | mchunkptr p = m->top; |
| 2829 | mchunkptr r = m->top = chunk_plus_offset(p, nb); |
| 2830 | r->head = rsize | PINUSE_BIT; |
| 2831 | set_size_and_pinuse_of_inuse_chunk(m, p, nb); |
| 2832 | check_top_chunk(m, m->top); |
| 2833 | check_malloced_chunk(m, chunk2mem(p), nb); |
| 2834 | return chunk2mem(p); |
| 2835 | } |
| 2836 | } |
| 2837 | |
| 2838 | MALLOC_FAILURE_ACTION; |
| 2839 | return 0; |
| 2840 | } |
| 2841 | |
| 2842 | /* ----------------------- system deallocation -------------------------- */ |
| 2843 | |
| 2844 | /* Unmap and unlink any mmapped segments that don't contain used chunks */ |
| 2845 | static size_t release_unused_segments(mstate m) { |
| 2846 | size_t released = 0; |
| 2847 | int nsegs = 0; |
| 2848 | msegmentptr pred = &m->seg; |
| 2849 | msegmentptr sp = pred->next; |
| 2850 | while (sp != 0) { |
| 2851 | char* base = sp->base; |
| 2852 | size_t size = sp->size; |
| 2853 | msegmentptr next = sp->next; |
| 2854 | ++nsegs; |
| 2855 | if (is_mmapped_segment(sp) && !is_extern_segment(sp)) { |
| 2856 | mchunkptr p = align_as_chunk(base); |
| 2857 | size_t psize = chunksize(p); |
| 2858 | /* Can unmap if first chunk holds entire segment and not pinned */ |
| 2859 | if (!is_inuse(p) && (char*)p + psize >= base + size - TOP_FOOT_SIZE) { |
| 2860 | tchunkptr tp = (tchunkptr)p; |
| 2861 | assert(segment_holds(sp, (char*)sp)); |
| 2862 | if (p == m->dv) { |
| 2863 | m->dv = 0; |
| 2864 | m->dvsize = 0; |
| 2865 | } |
| 2866 | else { |
| 2867 | unlink_large_chunk(m, tp); |
| 2868 | } |
| 2869 | if (CALL_MUNMAP(base, size) == 0) { |
| 2870 | released += size; |
| 2871 | m->footprint -= size; |
| 2872 | /* unlink obsoleted record */ |
| 2873 | sp = pred; |
| 2874 | sp->next = next; |
| 2875 | } |
| 2876 | else { /* back out if cannot unmap */ |
| 2877 | insert_large_chunk(m, tp, psize); |
| 2878 | } |
| 2879 | } |
| 2880 | } |
| 2881 | if (NO_SEGMENT_TRAVERSAL) /* scan only first segment */ |
| 2882 | break; |
| 2883 | pred = sp; |
| 2884 | sp = next; |
| 2885 | } |
| 2886 | /* Reset check counter */ |
| 2887 | m->release_checks = (((size_t) nsegs > (size_t) MAX_RELEASE_CHECK_RATE)? |
| 2888 | (size_t) nsegs : (size_t) MAX_RELEASE_CHECK_RATE); |
| 2889 | return released; |
| 2890 | } |
| 2891 | |
| 2892 | static int sys_trim(mstate m, size_t pad) { |
| 2893 | size_t released = 0; |
| 2894 | ensure_initialization(); |
| 2895 | if (pad < MAX_REQUEST && is_initialized(m)) { |
| 2896 | pad += TOP_FOOT_SIZE; /* ensure enough room for segment overhead */ |
| 2897 | |
| 2898 | if (m->topsize > pad) { |
| 2899 | /* Shrink top space in granularity-size units, keeping at least one */ |
| 2900 | size_t unit = mparams.granularity; |
| 2901 | size_t extra = ((m->topsize - pad + (unit - SIZE_T_ONE)) / unit - |
| 2902 | SIZE_T_ONE) * unit; |
| 2903 | msegmentptr sp = segment_holding(m, (char*)m->top); |
| 2904 | |
| 2905 | if (!is_extern_segment(sp)) { |
| 2906 | if (is_mmapped_segment(sp)) { |
| 2907 | if (HAVE_MMAP && |
| 2908 | sp->size >= extra && |
| 2909 | !has_segment_link(m, sp)) { /* can't shrink if pinned */ |
| 2910 | size_t newsize = sp->size - extra; |
| 2911 | (void)newsize; /* placate people compiling -Wunused-variable */ |
| 2912 | /* Prefer mremap, fall back to munmap */ |
| 2913 | if ((CALL_MREMAP(sp->base, sp->size, newsize, 0) != MFAIL) || |
| 2914 | (CALL_MUNMAP(sp->base + newsize, extra) == 0)) { |
| 2915 | released = extra; |
| 2916 | } |
| 2917 | } |
| 2918 | } |
| 2919 | else if (HAVE_MORECORE) { |
| 2920 | if (extra >= HALF_MAX_SIZE_T) /* Avoid wrapping negative */ |
| 2921 | extra = (HALF_MAX_SIZE_T) + SIZE_T_ONE - unit; |
| 2922 | ACQUIRE_MALLOC_GLOBAL_LOCK(); |
| 2923 | { |
| 2924 | /* Make sure end of memory is where we last set it. */ |
| 2925 | char* old_br = (char*)(CALL_MORECORE(0)); |
| 2926 | if (old_br == sp->base + sp->size) { |
| 2927 | char* rel_br = (char*)(CALL_MORECORE(-extra)); |
| 2928 | char* new_br = (char*)(CALL_MORECORE(0)); |
| 2929 | if (rel_br != CMFAIL && new_br < old_br) |
| 2930 | released = old_br - new_br; |
| 2931 | } |
| 2932 | } |
| 2933 | RELEASE_MALLOC_GLOBAL_LOCK(); |
| 2934 | } |
| 2935 | } |
| 2936 | |
| 2937 | if (released != 0) { |
| 2938 | sp->size -= released; |
| 2939 | m->footprint -= released; |
| 2940 | init_top(m, m->top, m->topsize - released); |
| 2941 | check_top_chunk(m, m->top); |
| 2942 | } |
| 2943 | } |
| 2944 | |
| 2945 | /* Unmap any unused mmapped segments */ |
| 2946 | if (HAVE_MMAP) |
| 2947 | released += release_unused_segments(m); |
| 2948 | |
| 2949 | /* On failure, disable autotrim to avoid repeated failed future calls */ |
| 2950 | if (released == 0 && m->topsize > m->trim_check) |
| 2951 | m->trim_check = MAX_SIZE_T; |
| 2952 | } |
| 2953 | |
| 2954 | return (released != 0)? 1 : 0; |
| 2955 | } |
| 2956 | |
| 2957 | /* Consolidate and bin a chunk. Differs from exported versions |
| 2958 | of free mainly in that the chunk need not be marked as inuse. |
| 2959 | */ |
| 2960 | static void dispose_chunk(mstate m, mchunkptr p, size_t psize) { |
| 2961 | mchunkptr next = chunk_plus_offset(p, psize); |
| 2962 | if (!pinuse(p)) { |
| 2963 | mchunkptr prev; |
| 2964 | size_t prevsize = p->prev_foot; |
| 2965 | if (is_mmapped(p)) { |
| 2966 | psize += prevsize + MMAP_FOOT_PAD; |
| 2967 | if (CALL_MUNMAP((char*)p - prevsize, psize) == 0) |
| 2968 | m->footprint -= psize; |
| 2969 | return; |
| 2970 | } |
| 2971 | prev = chunk_minus_offset(p, prevsize); |
| 2972 | psize += prevsize; |
| 2973 | p = prev; |
| 2974 | if (RTCHECK(ok_address(m, prev))) { /* consolidate backward */ |
| 2975 | if (p != m->dv) { |
| 2976 | unlink_chunk(m, p, prevsize); |
| 2977 | } |
| 2978 | else if ((next->head & INUSE_BITS) == INUSE_BITS) { |
| 2979 | m->dvsize = psize; |
| 2980 | set_free_with_pinuse(p, psize, next); |
| 2981 | return; |
| 2982 | } |
| 2983 | } |
| 2984 | else { |
| 2985 | CORRUPTION_ERROR_ACTION(m); |
| 2986 | return; |
| 2987 | } |
| 2988 | } |
| 2989 | if (RTCHECK(ok_address(m, next))) { |
| 2990 | if (!cinuse(next)) { /* consolidate forward */ |
| 2991 | if (next == m->top) { |
| 2992 | size_t tsize = m->topsize += psize; |
| 2993 | m->top = p; |
| 2994 | p->head = tsize | PINUSE_BIT; |
| 2995 | if (p == m->dv) { |
| 2996 | m->dv = 0; |
| 2997 | m->dvsize = 0; |
| 2998 | } |
| 2999 | return; |
| 3000 | } |
| 3001 | else if (next == m->dv) { |
| 3002 | size_t dsize = m->dvsize += psize; |
| 3003 | m->dv = p; |
| 3004 | set_size_and_pinuse_of_free_chunk(p, dsize); |
| 3005 | return; |
| 3006 | } |
| 3007 | else { |
| 3008 | size_t nsize = chunksize(next); |
| 3009 | psize += nsize; |
| 3010 | unlink_chunk(m, next, nsize); |
| 3011 | set_size_and_pinuse_of_free_chunk(p, psize); |
| 3012 | if (p == m->dv) { |
| 3013 | m->dvsize = psize; |
| 3014 | return; |
| 3015 | } |
| 3016 | } |
| 3017 | } |
| 3018 | else { |
| 3019 | set_free_with_pinuse(p, psize, next); |
| 3020 | } |
| 3021 | insert_chunk(m, p, psize); |
| 3022 | } |
| 3023 | else { |
| 3024 | CORRUPTION_ERROR_ACTION(m); |
| 3025 | } |
| 3026 | } |
| 3027 | |
| 3028 | /* ---------------------------- malloc --------------------------- */ |
| 3029 | |
| 3030 | /* allocate a large request from the best fitting chunk in a treebin */ |
| 3031 | static void* tmalloc_large(mstate m, size_t nb) { |
| 3032 | tchunkptr v = 0; |
| 3033 | size_t rsize = -nb; /* Unsigned negation */ |
| 3034 | tchunkptr t; |
| 3035 | bindex_t idx; |
| 3036 | compute_tree_index(nb, idx); |
| 3037 | if ((t = *treebin_at(m, idx)) != 0) { |
| 3038 | /* Traverse tree for this bin looking for node with size == nb */ |
| 3039 | size_t sizebits = nb << leftshift_for_tree_index(idx); |
| 3040 | tchunkptr rst = 0; /* The deepest untaken right subtree */ |
| 3041 | for (;;) { |
| 3042 | tchunkptr rt; |
| 3043 | size_t trem = chunksize(t) - nb; |
| 3044 | if (trem < rsize) { |
| 3045 | v = t; |
| 3046 | if ((rsize = trem) == 0) |
| 3047 | break; |
| 3048 | } |
| 3049 | rt = t->child[1]; |
| 3050 | t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]; |
| 3051 | if (rt != 0 && rt != t) |
| 3052 | rst = rt; |
| 3053 | if (t == 0) { |
| 3054 | t = rst; /* set t to least subtree holding sizes > nb */ |
| 3055 | break; |
| 3056 | } |
| 3057 | sizebits <<= 1; |
| 3058 | } |
| 3059 | } |
| 3060 | if (t == 0 && v == 0) { /* set t to root of next non-empty treebin */ |
| 3061 | binmap_t leftbits = left_bits(idx2bit(idx)) & m->treemap; |
| 3062 | if (leftbits != 0) { |
| 3063 | bindex_t i; |
| 3064 | binmap_t leastbit = least_bit(leftbits); |
| 3065 | compute_bit2idx(leastbit, i); |
| 3066 | t = *treebin_at(m, i); |
| 3067 | } |
| 3068 | } |
| 3069 | |
| 3070 | while (t != 0) { /* find smallest of tree or subtree */ |
| 3071 | size_t trem = chunksize(t) - nb; |
| 3072 | if (trem < rsize) { |
| 3073 | rsize = trem; |
| 3074 | v = t; |
| 3075 | } |
| 3076 | t = leftmost_child(t); |
| 3077 | } |
| 3078 | |
| 3079 | /* If dv is a better fit, return 0 so malloc will use it */ |
| 3080 | if (v != 0 && rsize < (size_t)(m->dvsize - nb)) { |
| 3081 | if (RTCHECK(ok_address(m, v))) { /* split */ |
| 3082 | mchunkptr r = chunk_plus_offset(v, nb); |
| 3083 | assert(chunksize(v) == rsize + nb); |
| 3084 | if (RTCHECK(ok_next(v, r))) { |
| 3085 | unlink_large_chunk(m, v); |
| 3086 | if (rsize < MIN_CHUNK_SIZE) |
| 3087 | set_inuse_and_pinuse(m, v, (rsize + nb)); |
| 3088 | else { |
| 3089 | set_size_and_pinuse_of_inuse_chunk(m, v, nb); |
| 3090 | set_size_and_pinuse_of_free_chunk(r, rsize); |
| 3091 | insert_chunk(m, r, rsize); |
| 3092 | } |
| 3093 | return chunk2mem(v); |
| 3094 | } |
| 3095 | } |
| 3096 | CORRUPTION_ERROR_ACTION(m); |
| 3097 | } |
| 3098 | return 0; |
| 3099 | } |
| 3100 | |
| 3101 | /* allocate a small request from the best fitting chunk in a treebin */ |
| 3102 | static void* tmalloc_small(mstate m, size_t nb) { |
| 3103 | tchunkptr t, v; |
| 3104 | size_t rsize; |
| 3105 | bindex_t i; |
| 3106 | binmap_t leastbit = least_bit(m->treemap); |
| 3107 | compute_bit2idx(leastbit, i); |
| 3108 | v = t = *treebin_at(m, i); |
| 3109 | rsize = chunksize(t) - nb; |
| 3110 | |
| 3111 | while ((t = leftmost_child(t)) != 0) { |
| 3112 | size_t trem = chunksize(t) - nb; |
| 3113 | if (trem < rsize) { |
| 3114 | rsize = trem; |
| 3115 | v = t; |
| 3116 | } |
| 3117 | } |
| 3118 | |
| 3119 | if (RTCHECK(ok_address(m, v))) { |
| 3120 | mchunkptr r = chunk_plus_offset(v, nb); |
| 3121 | assert(chunksize(v) == rsize + nb); |
| 3122 | if (RTCHECK(ok_next(v, r))) { |
| 3123 | unlink_large_chunk(m, v); |
| 3124 | if (rsize < MIN_CHUNK_SIZE) |
| 3125 | set_inuse_and_pinuse(m, v, (rsize + nb)); |
| 3126 | else { |
| 3127 | set_size_and_pinuse_of_inuse_chunk(m, v, nb); |
| 3128 | set_size_and_pinuse_of_free_chunk(r, rsize); |
| 3129 | replace_dv(m, r, rsize); |
| 3130 | } |
| 3131 | return chunk2mem(v); |
| 3132 | } |
| 3133 | } |
| 3134 | |
| 3135 | CORRUPTION_ERROR_ACTION(m); |
| 3136 | return 0; |
| 3137 | } |
| 3138 | |
| 3139 | #if !ONLY_MSPACES |
| 3140 | |
| 3141 | void* dlmalloc(size_t bytes) { |
| 3142 | /* |
| 3143 | Basic algorithm: |
| 3144 | If a small request (< 256 bytes minus per-chunk overhead): |
| 3145 | 1. If one exists, use a remainderless chunk in associated smallbin. |
| 3146 | (Remainderless means that there are too few excess bytes to |
| 3147 | represent as a chunk.) |
| 3148 | 2. If it is big enough, use the dv chunk, which is normally the |
| 3149 | chunk adjacent to the one used for the most recent small request. |
| 3150 | 3. If one exists, split the smallest available chunk in a bin, |
| 3151 | saving remainder in dv. |
| 3152 | 4. If it is big enough, use the top chunk. |
| 3153 | 5. If available, get memory from system and use it |
| 3154 | Otherwise, for a large request: |
| 3155 | 1. Find the smallest available binned chunk that fits, and use it |
| 3156 | if it is better fitting than dv chunk, splitting if necessary. |
| 3157 | 2. If better fitting than any binned chunk, use the dv chunk. |
| 3158 | 3. If it is big enough, use the top chunk. |
| 3159 | 4. If request size >= mmap threshold, try to directly mmap this chunk. |
| 3160 | 5. If available, get memory from system and use it |
| 3161 | |
| 3162 | The ugly goto's here ensure that postaction occurs along all paths. |
| 3163 | */ |
| 3164 | |
| 3165 | #if USE_LOCKS |
| 3166 | ensure_initialization(); /* initialize in sys_alloc if not using locks */ |
| 3167 | #endif |
| 3168 | |
| 3169 | if (!PREACTION(gm)) { |
| 3170 | void* mem; |
| 3171 | size_t nb; |
| 3172 | if (bytes <= MAX_SMALL_REQUEST) { |
| 3173 | bindex_t idx; |
| 3174 | binmap_t smallbits; |
| 3175 | nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes); |
| 3176 | idx = small_index(nb); |
| 3177 | smallbits = gm->smallmap >> idx; |
| 3178 | |
| 3179 | if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */ |
| 3180 | mchunkptr b, p; |
| 3181 | idx += ~smallbits & 1; /* Uses next bin if idx empty */ |
| 3182 | b = smallbin_at(gm, idx); |
| 3183 | p = b->fd; |
| 3184 | assert(chunksize(p) == small_index2size(idx)); |
| 3185 | unlink_first_small_chunk(gm, b, p, idx); |
| 3186 | set_inuse_and_pinuse(gm, p, small_index2size(idx)); |
| 3187 | mem = chunk2mem(p); |
| 3188 | check_malloced_chunk(gm, mem, nb); |
| 3189 | goto postaction; |
| 3190 | } |
| 3191 | |
| 3192 | else if (nb > gm->dvsize) { |
| 3193 | if (smallbits != 0) { /* Use chunk in next nonempty smallbin */ |
| 3194 | mchunkptr b, p, r; |
| 3195 | size_t rsize; |
| 3196 | bindex_t i; |
| 3197 | binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx)); |
| 3198 | binmap_t leastbit = least_bit(leftbits); |
| 3199 | compute_bit2idx(leastbit, i); |
| 3200 | b = smallbin_at(gm, i); |
| 3201 | p = b->fd; |
| 3202 | assert(chunksize(p) == small_index2size(i)); |
| 3203 | unlink_first_small_chunk(gm, b, p, i); |
| 3204 | rsize = small_index2size(i) - nb; |
| 3205 | /* Fit here cannot be remainderless if 4byte sizes */ |
| 3206 | if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE) |
| 3207 | set_inuse_and_pinuse(gm, p, small_index2size(i)); |
| 3208 | else { |
| 3209 | set_size_and_pinuse_of_inuse_chunk(gm, p, nb); |
| 3210 | r = chunk_plus_offset(p, nb); |
| 3211 | set_size_and_pinuse_of_free_chunk(r, rsize); |
| 3212 | replace_dv(gm, r, rsize); |
| 3213 | } |
| 3214 | mem = chunk2mem(p); |
| 3215 | check_malloced_chunk(gm, mem, nb); |
| 3216 | goto postaction; |
| 3217 | } |
| 3218 | |
| 3219 | else if (gm->treemap != 0 && (mem = tmalloc_small(gm, nb)) != 0) { |
| 3220 | check_malloced_chunk(gm, mem, nb); |
| 3221 | goto postaction; |
| 3222 | } |
| 3223 | } |
| 3224 | } |
| 3225 | else if (bytes >= MAX_REQUEST) |
| 3226 | nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */ |
| 3227 | else { |
| 3228 | nb = pad_request(bytes); |
| 3229 | if (gm->treemap != 0 && (mem = tmalloc_large(gm, nb)) != 0) { |
| 3230 | check_malloced_chunk(gm, mem, nb); |
| 3231 | goto postaction; |
| 3232 | } |
| 3233 | } |
| 3234 | |
| 3235 | if (nb <= gm->dvsize) { |
| 3236 | size_t rsize = gm->dvsize - nb; |
| 3237 | mchunkptr p = gm->dv; |
| 3238 | if (rsize >= MIN_CHUNK_SIZE) { /* split dv */ |
| 3239 | mchunkptr r = gm->dv = chunk_plus_offset(p, nb); |
| 3240 | gm->dvsize = rsize; |
| 3241 | set_size_and_pinuse_of_free_chunk(r, rsize); |
| 3242 | set_size_and_pinuse_of_inuse_chunk(gm, p, nb); |
| 3243 | } |
| 3244 | else { /* exhaust dv */ |
| 3245 | size_t dvs = gm->dvsize; |
| 3246 | gm->dvsize = 0; |
| 3247 | gm->dv = 0; |
| 3248 | set_inuse_and_pinuse(gm, p, dvs); |
| 3249 | } |
| 3250 | mem = chunk2mem(p); |
| 3251 | check_malloced_chunk(gm, mem, nb); |
| 3252 | goto postaction; |
| 3253 | } |
| 3254 | |
| 3255 | else if (nb < gm->topsize) { /* Split top */ |
| 3256 | size_t rsize = gm->topsize -= nb; |
| 3257 | mchunkptr p = gm->top; |
| 3258 | mchunkptr r = gm->top = chunk_plus_offset(p, nb); |
| 3259 | r->head = rsize | PINUSE_BIT; |
| 3260 | set_size_and_pinuse_of_inuse_chunk(gm, p, nb); |
| 3261 | mem = chunk2mem(p); |
| 3262 | check_top_chunk(gm, gm->top); |
| 3263 | check_malloced_chunk(gm, mem, nb); |
| 3264 | goto postaction; |
| 3265 | } |
| 3266 | |
| 3267 | mem = sys_alloc(gm, nb); |
| 3268 | |
| 3269 | postaction: |
| 3270 | POSTACTION(gm); |
| 3271 | return mem; |
| 3272 | } |
| 3273 | |
| 3274 | return 0; |
| 3275 | } |
| 3276 | |
| 3277 | /* ---------------------------- free --------------------------- */ |
| 3278 | |
| 3279 | void dlfree(void* mem) { |
| 3280 | /* |
Paul Vinciguerra | ec11b13 | 2018-09-24 05:25:00 -0700 | [diff] [blame] | 3281 | Consolidate freed chunks with preceding or succeeding bordering |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 3282 | free chunks, if they exist, and then place in a bin. Intermixed |
| 3283 | with special cases for top, dv, mmapped chunks, and usage errors. |
| 3284 | */ |
| 3285 | |
| 3286 | if (mem != 0) { |
| 3287 | mchunkptr p = mem2chunk(mem); |
| 3288 | #if FOOTERS |
| 3289 | mstate fm = get_mstate_for(p); |
| 3290 | if (!ok_magic(fm)) { |
| 3291 | USAGE_ERROR_ACTION(fm, p); |
| 3292 | return; |
| 3293 | } |
| 3294 | #else /* FOOTERS */ |
| 3295 | #define fm gm |
| 3296 | #endif /* FOOTERS */ |
| 3297 | if (!PREACTION(fm)) { |
| 3298 | check_inuse_chunk(fm, p); |
| 3299 | if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) { |
| 3300 | size_t psize = chunksize(p); |
| 3301 | mchunkptr next = chunk_plus_offset(p, psize); |
| 3302 | if (!pinuse(p)) { |
| 3303 | size_t prevsize = p->prev_foot; |
| 3304 | if (is_mmapped(p)) { |
| 3305 | psize += prevsize + MMAP_FOOT_PAD; |
| 3306 | if (CALL_MUNMAP((char*)p - prevsize, psize) == 0) |
| 3307 | fm->footprint -= psize; |
| 3308 | goto postaction; |
| 3309 | } |
| 3310 | else { |
| 3311 | mchunkptr prev = chunk_minus_offset(p, prevsize); |
| 3312 | psize += prevsize; |
| 3313 | p = prev; |
| 3314 | if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */ |
| 3315 | if (p != fm->dv) { |
| 3316 | unlink_chunk(fm, p, prevsize); |
| 3317 | } |
| 3318 | else if ((next->head & INUSE_BITS) == INUSE_BITS) { |
| 3319 | fm->dvsize = psize; |
| 3320 | set_free_with_pinuse(p, psize, next); |
| 3321 | goto postaction; |
| 3322 | } |
| 3323 | } |
| 3324 | else |
| 3325 | goto erroraction; |
| 3326 | } |
| 3327 | } |
| 3328 | |
| 3329 | if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) { |
| 3330 | if (!cinuse(next)) { /* consolidate forward */ |
| 3331 | if (next == fm->top) { |
| 3332 | size_t tsize = fm->topsize += psize; |
| 3333 | fm->top = p; |
| 3334 | p->head = tsize | PINUSE_BIT; |
| 3335 | if (p == fm->dv) { |
| 3336 | fm->dv = 0; |
| 3337 | fm->dvsize = 0; |
| 3338 | } |
| 3339 | if (should_trim(fm, tsize)) |
| 3340 | sys_trim(fm, 0); |
| 3341 | goto postaction; |
| 3342 | } |
| 3343 | else if (next == fm->dv) { |
| 3344 | size_t dsize = fm->dvsize += psize; |
| 3345 | fm->dv = p; |
| 3346 | set_size_and_pinuse_of_free_chunk(p, dsize); |
| 3347 | goto postaction; |
| 3348 | } |
| 3349 | else { |
| 3350 | size_t nsize = chunksize(next); |
| 3351 | psize += nsize; |
| 3352 | unlink_chunk(fm, next, nsize); |
| 3353 | set_size_and_pinuse_of_free_chunk(p, psize); |
| 3354 | if (p == fm->dv) { |
| 3355 | fm->dvsize = psize; |
| 3356 | goto postaction; |
| 3357 | } |
| 3358 | } |
| 3359 | } |
| 3360 | else |
| 3361 | set_free_with_pinuse(p, psize, next); |
| 3362 | |
| 3363 | if (is_small(psize)) { |
| 3364 | insert_small_chunk(fm, p, psize); |
| 3365 | check_free_chunk(fm, p); |
| 3366 | } |
| 3367 | else { |
| 3368 | tchunkptr tp = (tchunkptr)p; |
| 3369 | insert_large_chunk(fm, tp, psize); |
| 3370 | check_free_chunk(fm, p); |
| 3371 | if (--fm->release_checks == 0) |
| 3372 | release_unused_segments(fm); |
| 3373 | } |
| 3374 | goto postaction; |
| 3375 | } |
| 3376 | } |
| 3377 | erroraction: |
| 3378 | USAGE_ERROR_ACTION(fm, p); |
| 3379 | postaction: |
| 3380 | POSTACTION(fm); |
| 3381 | } |
| 3382 | } |
| 3383 | #if !FOOTERS |
| 3384 | #undef fm |
| 3385 | #endif /* FOOTERS */ |
| 3386 | } |
| 3387 | |
| 3388 | void* dlcalloc(size_t n_elements, size_t elem_size) { |
| 3389 | void* mem; |
| 3390 | size_t req = 0; |
| 3391 | if (n_elements != 0) { |
| 3392 | req = n_elements * elem_size; |
| 3393 | if (((n_elements | elem_size) & ~(size_t)0xffff) && |
| 3394 | (req / n_elements != elem_size)) |
| 3395 | req = MAX_SIZE_T; /* force downstream failure on overflow */ |
| 3396 | } |
| 3397 | mem = dlmalloc(req); |
| 3398 | if (mem != 0 && calloc_must_clear(mem2chunk(mem))) |
| 3399 | memset(mem, 0, req); |
| 3400 | return mem; |
| 3401 | } |
| 3402 | |
| 3403 | #endif /* !ONLY_MSPACES */ |
| 3404 | |
| 3405 | /* ------------ Internal support for realloc, memalign, etc -------------- */ |
| 3406 | |
| 3407 | /* Try to realloc; only in-place unless can_move true */ |
| 3408 | static mchunkptr try_realloc_chunk(mstate m, mchunkptr p, size_t nb, |
| 3409 | int can_move) { |
| 3410 | mchunkptr newp = 0; |
| 3411 | size_t oldsize = chunksize(p); |
| 3412 | mchunkptr next = chunk_plus_offset(p, oldsize); |
| 3413 | if (RTCHECK(ok_address(m, p) && ok_inuse(p) && |
| 3414 | ok_next(p, next) && ok_pinuse(next))) { |
| 3415 | if (is_mmapped(p)) { |
| 3416 | newp = mmap_resize(m, p, nb, can_move); |
| 3417 | } |
| 3418 | else if (oldsize >= nb) { /* already big enough */ |
| 3419 | size_t rsize = oldsize - nb; |
| 3420 | if (rsize >= MIN_CHUNK_SIZE) { /* split off remainder */ |
| 3421 | mchunkptr r = chunk_plus_offset(p, nb); |
| 3422 | set_inuse(m, p, nb); |
| 3423 | set_inuse(m, r, rsize); |
| 3424 | dispose_chunk(m, r, rsize); |
| 3425 | } |
| 3426 | newp = p; |
| 3427 | } |
| 3428 | else if (next == m->top) { /* extend into top */ |
| 3429 | if (oldsize + m->topsize > nb) { |
| 3430 | size_t newsize = oldsize + m->topsize; |
| 3431 | size_t newtopsize = newsize - nb; |
| 3432 | mchunkptr newtop = chunk_plus_offset(p, nb); |
| 3433 | set_inuse(m, p, nb); |
| 3434 | newtop->head = newtopsize |PINUSE_BIT; |
| 3435 | m->top = newtop; |
| 3436 | m->topsize = newtopsize; |
| 3437 | newp = p; |
| 3438 | } |
| 3439 | } |
| 3440 | else if (next == m->dv) { /* extend into dv */ |
| 3441 | size_t dvs = m->dvsize; |
| 3442 | if (oldsize + dvs >= nb) { |
| 3443 | size_t dsize = oldsize + dvs - nb; |
| 3444 | if (dsize >= MIN_CHUNK_SIZE) { |
| 3445 | mchunkptr r = chunk_plus_offset(p, nb); |
| 3446 | mchunkptr n = chunk_plus_offset(r, dsize); |
| 3447 | set_inuse(m, p, nb); |
| 3448 | set_size_and_pinuse_of_free_chunk(r, dsize); |
| 3449 | clear_pinuse(n); |
| 3450 | m->dvsize = dsize; |
| 3451 | m->dv = r; |
| 3452 | } |
| 3453 | else { /* exhaust dv */ |
| 3454 | size_t newsize = oldsize + dvs; |
| 3455 | set_inuse(m, p, newsize); |
| 3456 | m->dvsize = 0; |
| 3457 | m->dv = 0; |
| 3458 | } |
| 3459 | newp = p; |
| 3460 | } |
| 3461 | } |
| 3462 | else if (!cinuse(next)) { /* extend into next free chunk */ |
| 3463 | size_t nextsize = chunksize(next); |
| 3464 | if (oldsize + nextsize >= nb) { |
| 3465 | size_t rsize = oldsize + nextsize - nb; |
| 3466 | unlink_chunk(m, next, nextsize); |
| 3467 | if (rsize < MIN_CHUNK_SIZE) { |
| 3468 | size_t newsize = oldsize + nextsize; |
| 3469 | set_inuse(m, p, newsize); |
| 3470 | } |
| 3471 | else { |
| 3472 | mchunkptr r = chunk_plus_offset(p, nb); |
| 3473 | set_inuse(m, p, nb); |
| 3474 | set_inuse(m, r, rsize); |
| 3475 | dispose_chunk(m, r, rsize); |
| 3476 | } |
| 3477 | newp = p; |
| 3478 | } |
| 3479 | } |
| 3480 | } |
| 3481 | else { |
| 3482 | USAGE_ERROR_ACTION(m, chunk2mem(p)); |
| 3483 | } |
| 3484 | return newp; |
| 3485 | } |
| 3486 | |
| 3487 | static void* internal_memalign(mstate m, size_t alignment, size_t bytes) { |
| 3488 | void* mem = 0; |
| 3489 | if (alignment < MIN_CHUNK_SIZE) /* must be at least a minimum chunk size */ |
| 3490 | alignment = MIN_CHUNK_SIZE; |
| 3491 | if ((alignment & (alignment-SIZE_T_ONE)) != 0) {/* Ensure a power of 2 */ |
| 3492 | size_t a = MALLOC_ALIGNMENT << 1; |
| 3493 | while (a < alignment) a <<= 1; |
| 3494 | alignment = a; |
| 3495 | } |
| 3496 | if (bytes >= MAX_REQUEST - alignment) { |
| 3497 | if (m != 0) { /* Test isn't needed but avoids compiler warning */ |
| 3498 | MALLOC_FAILURE_ACTION; |
| 3499 | } |
| 3500 | } |
| 3501 | else { |
| 3502 | size_t nb = request2size(bytes); |
| 3503 | size_t req = nb + alignment + MIN_CHUNK_SIZE - CHUNK_OVERHEAD; |
| 3504 | mem = internal_malloc(m, req); |
| 3505 | if (mem != 0) { |
| 3506 | mchunkptr p = mem2chunk(mem); |
| 3507 | if (PREACTION(m)) |
| 3508 | return 0; |
| 3509 | if ((((size_t)(mem)) & (alignment - 1)) != 0) { /* misaligned */ |
| 3510 | /* |
| 3511 | Find an aligned spot inside chunk. Since we need to give |
| 3512 | back leading space in a chunk of at least MIN_CHUNK_SIZE, if |
| 3513 | the first calculation places us at a spot with less than |
| 3514 | MIN_CHUNK_SIZE leader, we can move to the next aligned spot. |
| 3515 | We've allocated enough total room so that this is always |
| 3516 | possible. |
| 3517 | */ |
| 3518 | char* br = (char*)mem2chunk((size_t)(((size_t)((char*)mem + alignment - |
| 3519 | SIZE_T_ONE)) & |
| 3520 | -alignment)); |
| 3521 | char* pos = ((size_t)(br - (char*)(p)) >= MIN_CHUNK_SIZE)? |
| 3522 | br : br+alignment; |
| 3523 | mchunkptr newp = (mchunkptr)pos; |
| 3524 | size_t leadsize = pos - (char*)(p); |
| 3525 | size_t newsize = chunksize(p) - leadsize; |
| 3526 | |
| 3527 | if (is_mmapped(p)) { /* For mmapped chunks, just adjust offset */ |
| 3528 | newp->prev_foot = p->prev_foot + leadsize; |
| 3529 | newp->head = newsize; |
| 3530 | } |
| 3531 | else { /* Otherwise, give back leader, use the rest */ |
| 3532 | set_inuse(m, newp, newsize); |
| 3533 | set_inuse(m, p, leadsize); |
| 3534 | dispose_chunk(m, p, leadsize); |
| 3535 | } |
| 3536 | p = newp; |
| 3537 | } |
| 3538 | |
| 3539 | /* Give back spare room at the end */ |
| 3540 | if (!is_mmapped(p)) { |
| 3541 | size_t size = chunksize(p); |
| 3542 | if (size > nb + MIN_CHUNK_SIZE) { |
| 3543 | size_t remainder_size = size - nb; |
| 3544 | mchunkptr remainder = chunk_plus_offset(p, nb); |
| 3545 | set_inuse(m, p, nb); |
| 3546 | set_inuse(m, remainder, remainder_size); |
| 3547 | dispose_chunk(m, remainder, remainder_size); |
| 3548 | } |
| 3549 | } |
| 3550 | |
| 3551 | mem = chunk2mem(p); |
| 3552 | assert (chunksize(p) >= nb); |
| 3553 | assert(((size_t)mem & (alignment - 1)) == 0); |
| 3554 | check_inuse_chunk(m, p); |
| 3555 | POSTACTION(m); |
| 3556 | } |
| 3557 | } |
| 3558 | return mem; |
| 3559 | } |
| 3560 | |
| 3561 | /* |
| 3562 | Common support for independent_X routines, handling |
| 3563 | all of the combinations that can result. |
| 3564 | The opts arg has: |
| 3565 | bit 0 set if all elements are same size (using sizes[0]) |
| 3566 | bit 1 set if elements should be zeroed |
| 3567 | */ |
| 3568 | static void** ialloc(mstate m, |
| 3569 | size_t n_elements, |
| 3570 | size_t* sizes, |
| 3571 | int opts, |
| 3572 | void* chunks[]) { |
| 3573 | |
| 3574 | size_t element_size; /* chunksize of each element, if all same */ |
| 3575 | size_t contents_size; /* total size of elements */ |
| 3576 | size_t array_size; /* request size of pointer array */ |
| 3577 | void* mem; /* malloced aggregate space */ |
| 3578 | mchunkptr p; /* corresponding chunk */ |
| 3579 | size_t remainder_size; /* remaining bytes while splitting */ |
| 3580 | void** marray; /* either "chunks" or malloced ptr array */ |
| 3581 | mchunkptr array_chunk; /* chunk for malloced ptr array */ |
| 3582 | flag_t was_enabled; /* to disable mmap */ |
| 3583 | size_t size; |
| 3584 | size_t i; |
| 3585 | |
| 3586 | ensure_initialization(); |
| 3587 | /* compute array length, if needed */ |
| 3588 | if (chunks != 0) { |
| 3589 | if (n_elements == 0) |
| 3590 | return chunks; /* nothing to do */ |
| 3591 | marray = chunks; |
| 3592 | array_size = 0; |
| 3593 | } |
| 3594 | else { |
| 3595 | /* if empty req, must still return chunk representing empty array */ |
| 3596 | if (n_elements == 0) |
| 3597 | return (void**)internal_malloc(m, 0); |
| 3598 | marray = 0; |
| 3599 | array_size = request2size(n_elements * (sizeof(void*))); |
| 3600 | } |
| 3601 | |
| 3602 | /* compute total element size */ |
| 3603 | if (opts & 0x1) { /* all-same-size */ |
| 3604 | element_size = request2size(*sizes); |
| 3605 | contents_size = n_elements * element_size; |
| 3606 | } |
| 3607 | else { /* add up all the sizes */ |
| 3608 | element_size = 0; |
| 3609 | contents_size = 0; |
| 3610 | for (i = 0; i != n_elements; ++i) |
| 3611 | contents_size += request2size(sizes[i]); |
| 3612 | } |
| 3613 | |
| 3614 | size = contents_size + array_size; |
| 3615 | |
| 3616 | /* |
| 3617 | Allocate the aggregate chunk. First disable direct-mmapping so |
| 3618 | malloc won't use it, since we would not be able to later |
| 3619 | free/realloc space internal to a segregated mmap region. |
| 3620 | */ |
| 3621 | was_enabled = use_mmap(m); |
| 3622 | disable_mmap(m); |
| 3623 | mem = internal_malloc(m, size - CHUNK_OVERHEAD); |
| 3624 | if (was_enabled) |
| 3625 | enable_mmap(m); |
| 3626 | if (mem == 0) |
| 3627 | return 0; |
| 3628 | |
| 3629 | if (PREACTION(m)) return 0; |
| 3630 | p = mem2chunk(mem); |
| 3631 | remainder_size = chunksize(p); |
| 3632 | |
| 3633 | assert(!is_mmapped(p)); |
| 3634 | |
| 3635 | if (opts & 0x2) { /* optionally clear the elements */ |
| 3636 | memset((size_t*)mem, 0, remainder_size - SIZE_T_SIZE - array_size); |
| 3637 | } |
| 3638 | |
| 3639 | /* If not provided, allocate the pointer array as final part of chunk */ |
| 3640 | if (marray == 0) { |
| 3641 | size_t array_chunk_size; |
| 3642 | array_chunk = chunk_plus_offset(p, contents_size); |
| 3643 | array_chunk_size = remainder_size - contents_size; |
| 3644 | marray = (void**) (chunk2mem(array_chunk)); |
| 3645 | set_size_and_pinuse_of_inuse_chunk(m, array_chunk, array_chunk_size); |
| 3646 | remainder_size = contents_size; |
| 3647 | } |
| 3648 | |
| 3649 | /* split out elements */ |
| 3650 | for (i = 0; ; ++i) { |
| 3651 | marray[i] = chunk2mem(p); |
| 3652 | if (i != n_elements-1) { |
| 3653 | if (element_size != 0) |
| 3654 | size = element_size; |
| 3655 | else |
| 3656 | size = request2size(sizes[i]); |
| 3657 | remainder_size -= size; |
| 3658 | set_size_and_pinuse_of_inuse_chunk(m, p, size); |
| 3659 | p = chunk_plus_offset(p, size); |
| 3660 | } |
| 3661 | else { /* the final element absorbs any overallocation slop */ |
| 3662 | set_size_and_pinuse_of_inuse_chunk(m, p, remainder_size); |
| 3663 | break; |
| 3664 | } |
| 3665 | } |
| 3666 | |
| 3667 | #if DEBUG |
| 3668 | if (marray != chunks) { |
| 3669 | /* final element must have exactly exhausted chunk */ |
| 3670 | if (element_size != 0) { |
| 3671 | assert(remainder_size == element_size); |
| 3672 | } |
| 3673 | else { |
| 3674 | assert(remainder_size == request2size(sizes[i])); |
| 3675 | } |
| 3676 | check_inuse_chunk(m, mem2chunk(marray)); |
| 3677 | } |
| 3678 | for (i = 0; i != n_elements; ++i) |
| 3679 | check_inuse_chunk(m, mem2chunk(marray[i])); |
| 3680 | |
| 3681 | #endif /* DEBUG */ |
| 3682 | |
| 3683 | POSTACTION(m); |
| 3684 | return marray; |
| 3685 | } |
| 3686 | |
| 3687 | /* Try to free all pointers in the given array. |
| 3688 | Note: this could be made faster, by delaying consolidation, |
| 3689 | at the price of disabling some user integrity checks, We |
| 3690 | still optimize some consolidations by combining adjacent |
| 3691 | chunks before freeing, which will occur often if allocated |
| 3692 | with ialloc or the array is sorted. |
| 3693 | */ |
| 3694 | static size_t internal_bulk_free(mstate m, void* array[], size_t nelem) { |
| 3695 | size_t unfreed = 0; |
| 3696 | if (!PREACTION(m)) { |
| 3697 | void** a; |
| 3698 | void** fence = &(array[nelem]); |
| 3699 | for (a = array; a != fence; ++a) { |
| 3700 | void* mem = *a; |
| 3701 | if (mem != 0) { |
| 3702 | mchunkptr p = mem2chunk(mem); |
| 3703 | size_t psize = chunksize(p); |
| 3704 | #if FOOTERS |
| 3705 | if (get_mstate_for(p) != m) { |
| 3706 | ++unfreed; |
| 3707 | continue; |
| 3708 | } |
| 3709 | #endif |
| 3710 | check_inuse_chunk(m, p); |
| 3711 | *a = 0; |
| 3712 | if (RTCHECK(ok_address(m, p) && ok_inuse(p))) { |
| 3713 | void ** b = a + 1; /* try to merge with next chunk */ |
| 3714 | mchunkptr next = next_chunk(p); |
| 3715 | if (b != fence && *b == chunk2mem(next)) { |
| 3716 | size_t newsize = chunksize(next) + psize; |
| 3717 | set_inuse(m, p, newsize); |
| 3718 | *b = chunk2mem(p); |
| 3719 | } |
| 3720 | else |
| 3721 | dispose_chunk(m, p, psize); |
| 3722 | } |
| 3723 | else { |
| 3724 | CORRUPTION_ERROR_ACTION(m); |
| 3725 | break; |
| 3726 | } |
| 3727 | } |
| 3728 | } |
| 3729 | if (should_trim(m, m->topsize)) |
| 3730 | sys_trim(m, 0); |
| 3731 | POSTACTION(m); |
| 3732 | } |
| 3733 | return unfreed; |
| 3734 | } |
| 3735 | |
| 3736 | /* Traversal */ |
| 3737 | #if MALLOC_INSPECT_ALL |
| 3738 | static void internal_inspect_all(mstate m, |
| 3739 | void(*handler)(void *start, |
| 3740 | void *end, |
| 3741 | size_t used_bytes, |
| 3742 | void* callback_arg), |
| 3743 | void* arg) { |
| 3744 | if (is_initialized(m)) { |
| 3745 | mchunkptr top = m->top; |
| 3746 | msegmentptr s; |
| 3747 | for (s = &m->seg; s != 0; s = s->next) { |
| 3748 | mchunkptr q = align_as_chunk(s->base); |
| 3749 | while (segment_holds(s, q) && q->head != FENCEPOST_HEAD) { |
| 3750 | mchunkptr next = next_chunk(q); |
| 3751 | size_t sz = chunksize(q); |
| 3752 | size_t used; |
| 3753 | void* start; |
| 3754 | if (is_inuse(q)) { |
| 3755 | used = sz - CHUNK_OVERHEAD; /* must not be mmapped */ |
| 3756 | start = chunk2mem(q); |
| 3757 | } |
| 3758 | else { |
| 3759 | used = 0; |
| 3760 | if (is_small(sz)) { /* offset by possible bookkeeping */ |
| 3761 | start = (void*)((char*)q + sizeof(struct malloc_chunk)); |
| 3762 | } |
| 3763 | else { |
| 3764 | start = (void*)((char*)q + sizeof(struct malloc_tree_chunk)); |
| 3765 | } |
| 3766 | } |
| 3767 | if (start < (void*)next) /* skip if all space is bookkeeping */ |
| 3768 | handler(start, next, used, arg); |
| 3769 | if (q == top) |
| 3770 | break; |
| 3771 | q = next; |
| 3772 | } |
| 3773 | } |
| 3774 | } |
| 3775 | } |
| 3776 | #endif /* MALLOC_INSPECT_ALL */ |
| 3777 | |
| 3778 | /* ------------------ Exported realloc, memalign, etc -------------------- */ |
| 3779 | |
| 3780 | #if !ONLY_MSPACES |
| 3781 | |
| 3782 | void* dlrealloc(void* oldmem, size_t bytes) { |
| 3783 | void* mem = 0; |
| 3784 | if (oldmem == 0) { |
| 3785 | mem = dlmalloc(bytes); |
| 3786 | } |
| 3787 | else if (bytes >= MAX_REQUEST) { |
| 3788 | MALLOC_FAILURE_ACTION; |
| 3789 | } |
| 3790 | #ifdef REALLOC_ZERO_BYTES_FREES |
| 3791 | else if (bytes == 0) { |
| 3792 | dlfree(oldmem); |
| 3793 | } |
| 3794 | #endif /* REALLOC_ZERO_BYTES_FREES */ |
| 3795 | else { |
| 3796 | size_t nb = request2size(bytes); |
| 3797 | mchunkptr oldp = mem2chunk(oldmem); |
| 3798 | #if ! FOOTERS |
| 3799 | mstate m = gm; |
| 3800 | #else /* FOOTERS */ |
| 3801 | mstate m = get_mstate_for(oldp); |
| 3802 | if (!ok_magic(m)) { |
| 3803 | USAGE_ERROR_ACTION(m, oldmem); |
| 3804 | return 0; |
| 3805 | } |
| 3806 | #endif /* FOOTERS */ |
| 3807 | if (!PREACTION(m)) { |
| 3808 | mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1); |
| 3809 | POSTACTION(m); |
| 3810 | if (newp != 0) { |
| 3811 | check_inuse_chunk(m, newp); |
| 3812 | mem = chunk2mem(newp); |
| 3813 | } |
| 3814 | else { |
| 3815 | mem = internal_malloc(m, bytes); |
| 3816 | if (mem != 0) { |
| 3817 | size_t oc = chunksize(oldp) - overhead_for(oldp); |
| 3818 | memcpy(mem, oldmem, (oc < bytes)? oc : bytes); |
| 3819 | internal_free(m, oldmem); |
| 3820 | } |
| 3821 | } |
| 3822 | } |
| 3823 | } |
| 3824 | return mem; |
| 3825 | } |
| 3826 | |
| 3827 | void* dlrealloc_in_place(void* oldmem, size_t bytes) { |
| 3828 | void* mem = 0; |
| 3829 | if (oldmem != 0) { |
| 3830 | if (bytes >= MAX_REQUEST) { |
| 3831 | MALLOC_FAILURE_ACTION; |
| 3832 | } |
| 3833 | else { |
| 3834 | size_t nb = request2size(bytes); |
| 3835 | mchunkptr oldp = mem2chunk(oldmem); |
| 3836 | #if ! FOOTERS |
| 3837 | mstate m = gm; |
| 3838 | #else /* FOOTERS */ |
| 3839 | mstate m = get_mstate_for(oldp); |
| 3840 | if (!ok_magic(m)) { |
| 3841 | USAGE_ERROR_ACTION(m, oldmem); |
| 3842 | return 0; |
| 3843 | } |
| 3844 | #endif /* FOOTERS */ |
| 3845 | if (!PREACTION(m)) { |
| 3846 | mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0); |
| 3847 | POSTACTION(m); |
| 3848 | if (newp == oldp) { |
| 3849 | check_inuse_chunk(m, newp); |
| 3850 | mem = oldmem; |
| 3851 | } |
| 3852 | } |
| 3853 | } |
| 3854 | } |
| 3855 | return mem; |
| 3856 | } |
| 3857 | |
| 3858 | void* dlmemalign(size_t alignment, size_t bytes) { |
| 3859 | if (alignment <= MALLOC_ALIGNMENT) { |
| 3860 | return dlmalloc(bytes); |
| 3861 | } |
| 3862 | return internal_memalign(gm, alignment, bytes); |
| 3863 | } |
| 3864 | |
| 3865 | int dlposix_memalign(void** pp, size_t alignment, size_t bytes) { |
| 3866 | void* mem = 0; |
| 3867 | if (alignment == MALLOC_ALIGNMENT) |
| 3868 | mem = dlmalloc(bytes); |
| 3869 | else { |
| 3870 | size_t d = alignment / sizeof(void*); |
| 3871 | size_t r = alignment % sizeof(void*); |
| 3872 | if (r != 0 || d == 0 || (d & (d-SIZE_T_ONE)) != 0) |
| 3873 | return EINVAL; |
| 3874 | else if (bytes <= MAX_REQUEST - alignment) { |
| 3875 | if (alignment < MIN_CHUNK_SIZE) |
| 3876 | alignment = MIN_CHUNK_SIZE; |
| 3877 | mem = internal_memalign(gm, alignment, bytes); |
| 3878 | } |
| 3879 | } |
| 3880 | if (mem == 0) |
| 3881 | return ENOMEM; |
| 3882 | else { |
| 3883 | *pp = mem; |
| 3884 | return 0; |
| 3885 | } |
| 3886 | } |
| 3887 | |
| 3888 | void* dlvalloc(size_t bytes) { |
| 3889 | size_t pagesz; |
| 3890 | ensure_initialization(); |
| 3891 | pagesz = mparams.page_size; |
| 3892 | return dlmemalign(pagesz, bytes); |
| 3893 | } |
| 3894 | |
| 3895 | void* dlpvalloc(size_t bytes) { |
| 3896 | size_t pagesz; |
| 3897 | ensure_initialization(); |
| 3898 | pagesz = mparams.page_size; |
| 3899 | return dlmemalign(pagesz, (bytes + pagesz - SIZE_T_ONE) & ~(pagesz - SIZE_T_ONE)); |
| 3900 | } |
| 3901 | |
| 3902 | void** dlindependent_calloc(size_t n_elements, size_t elem_size, |
| 3903 | void* chunks[]) { |
| 3904 | size_t sz = elem_size; /* serves as 1-element array */ |
| 3905 | return ialloc(gm, n_elements, &sz, 3, chunks); |
| 3906 | } |
| 3907 | |
| 3908 | void** dlindependent_comalloc(size_t n_elements, size_t sizes[], |
| 3909 | void* chunks[]) { |
| 3910 | return ialloc(gm, n_elements, sizes, 0, chunks); |
| 3911 | } |
| 3912 | |
| 3913 | size_t dlbulk_free(void* array[], size_t nelem) { |
| 3914 | return internal_bulk_free(gm, array, nelem); |
| 3915 | } |
| 3916 | |
| 3917 | #if MALLOC_INSPECT_ALL |
| 3918 | void dlmalloc_inspect_all(void(*handler)(void *start, |
| 3919 | void *end, |
| 3920 | size_t used_bytes, |
| 3921 | void* callback_arg), |
| 3922 | void* arg) { |
| 3923 | ensure_initialization(); |
| 3924 | if (!PREACTION(gm)) { |
| 3925 | internal_inspect_all(gm, handler, arg); |
| 3926 | POSTACTION(gm); |
| 3927 | } |
| 3928 | } |
| 3929 | #endif /* MALLOC_INSPECT_ALL */ |
| 3930 | |
| 3931 | int dlmalloc_trim(size_t pad) { |
| 3932 | int result = 0; |
| 3933 | ensure_initialization(); |
| 3934 | if (!PREACTION(gm)) { |
| 3935 | result = sys_trim(gm, pad); |
| 3936 | POSTACTION(gm); |
| 3937 | } |
| 3938 | return result; |
| 3939 | } |
| 3940 | |
| 3941 | size_t dlmalloc_footprint(void) { |
| 3942 | return gm->footprint; |
| 3943 | } |
| 3944 | |
| 3945 | size_t dlmalloc_max_footprint(void) { |
| 3946 | return gm->max_footprint; |
| 3947 | } |
| 3948 | |
| 3949 | size_t dlmalloc_footprint_limit(void) { |
| 3950 | size_t maf = gm->footprint_limit; |
| 3951 | return maf == 0 ? MAX_SIZE_T : maf; |
| 3952 | } |
| 3953 | |
| 3954 | size_t dlmalloc_set_footprint_limit(size_t bytes) { |
| 3955 | size_t result; /* invert sense of 0 */ |
| 3956 | if (bytes == 0) |
| 3957 | result = granularity_align(1); /* Use minimal size */ |
| 3958 | if (bytes == MAX_SIZE_T) |
| 3959 | result = 0; /* disable */ |
| 3960 | else |
| 3961 | result = granularity_align(bytes); |
| 3962 | return gm->footprint_limit = result; |
| 3963 | } |
| 3964 | |
| 3965 | #if !NO_MALLINFO |
Dave Barach | af7dd5b | 2018-08-23 17:08:44 -0400 | [diff] [blame] | 3966 | struct dlmallinfo dlmallinfo(void) { |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 3967 | return internal_mallinfo(gm); |
| 3968 | } |
| 3969 | #endif /* NO_MALLINFO */ |
| 3970 | |
| 3971 | #if !NO_MALLOC_STATS |
| 3972 | void dlmalloc_stats() { |
| 3973 | internal_malloc_stats(gm); |
| 3974 | } |
| 3975 | #endif /* NO_MALLOC_STATS */ |
| 3976 | |
| 3977 | int dlmallopt(int param_number, int value) { |
| 3978 | return change_mparam(param_number, value); |
| 3979 | } |
| 3980 | |
| 3981 | size_t dlmalloc_usable_size(void* mem) { |
| 3982 | if (mem != 0) { |
| 3983 | mchunkptr p = mem2chunk(mem); |
| 3984 | if (is_inuse(p)) |
| 3985 | return chunksize(p) - overhead_for(p); |
| 3986 | } |
| 3987 | return 0; |
| 3988 | } |
| 3989 | |
| 3990 | #endif /* !ONLY_MSPACES */ |
| 3991 | |
| 3992 | /* ----------------------------- user mspaces ---------------------------- */ |
| 3993 | |
| 3994 | #if MSPACES |
| 3995 | |
| 3996 | static mstate init_user_mstate(char* tbase, size_t tsize) { |
| 3997 | size_t msize = pad_request(sizeof(struct malloc_state)); |
| 3998 | mchunkptr mn; |
| 3999 | mchunkptr msp = align_as_chunk(tbase); |
| 4000 | mstate m = (mstate)(chunk2mem(msp)); |
| 4001 | memset(m, 0, msize); |
| 4002 | (void)INITIAL_LOCK(&m->mutex); |
| 4003 | msp->head = (msize|INUSE_BITS); |
| 4004 | m->seg.base = m->least_addr = tbase; |
| 4005 | m->seg.size = m->footprint = m->max_footprint = tsize; |
| 4006 | m->magic = mparams.magic; |
| 4007 | m->release_checks = MAX_RELEASE_CHECK_RATE; |
| 4008 | m->mflags = mparams.default_mflags; |
| 4009 | m->extp = 0; |
| 4010 | m->exts = 0; |
| 4011 | disable_contiguous(m); |
| 4012 | init_bins(m); |
| 4013 | mn = next_chunk(mem2chunk(m)); |
| 4014 | init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) - TOP_FOOT_SIZE); |
| 4015 | check_top_chunk(m, m->top); |
| 4016 | return m; |
| 4017 | } |
| 4018 | |
| 4019 | mspace create_mspace(size_t capacity, int locked) { |
| 4020 | mstate m = 0; |
| 4021 | size_t msize; |
| 4022 | ensure_initialization(); |
| 4023 | msize = pad_request(sizeof(struct malloc_state)); |
| 4024 | if (capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) { |
| 4025 | size_t rs = ((capacity == 0)? mparams.granularity : |
| 4026 | (capacity + TOP_FOOT_SIZE + msize)); |
| 4027 | size_t tsize = granularity_align(rs); |
| 4028 | char* tbase = (char*)(CALL_MMAP(tsize)); |
| 4029 | if (tbase != CMFAIL) { |
| 4030 | m = init_user_mstate(tbase, tsize); |
| 4031 | m->seg.sflags = USE_MMAP_BIT; |
| 4032 | set_lock(m, locked); |
| 4033 | } |
| 4034 | } |
| 4035 | return (mspace)m; |
| 4036 | } |
| 4037 | |
| 4038 | mspace create_mspace_with_base(void* base, size_t capacity, int locked) { |
| 4039 | mstate m = 0; |
| 4040 | size_t msize; |
| 4041 | ensure_initialization(); |
| 4042 | msize = pad_request(sizeof(struct malloc_state)); |
| 4043 | if (capacity > msize + TOP_FOOT_SIZE && |
| 4044 | capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) { |
| 4045 | m = init_user_mstate((char*)base, capacity); |
| 4046 | m->seg.sflags = EXTERN_BIT; |
| 4047 | set_lock(m, locked); |
| 4048 | } |
| 4049 | return (mspace)m; |
| 4050 | } |
| 4051 | |
| 4052 | int mspace_track_large_chunks(mspace msp, int enable) { |
| 4053 | int ret = 0; |
| 4054 | mstate ms = (mstate)msp; |
| 4055 | if (!PREACTION(ms)) { |
| 4056 | if (!use_mmap(ms)) { |
| 4057 | ret = 1; |
| 4058 | } |
| 4059 | if (!enable) { |
| 4060 | enable_mmap(ms); |
| 4061 | } else { |
| 4062 | disable_mmap(ms); |
| 4063 | } |
| 4064 | POSTACTION(ms); |
| 4065 | } |
| 4066 | return ret; |
| 4067 | } |
| 4068 | |
| 4069 | size_t destroy_mspace(mspace msp) { |
| 4070 | size_t freed = 0; |
| 4071 | mstate ms = (mstate)msp; |
| 4072 | if (ok_magic(ms)) { |
| 4073 | msegmentptr sp = &ms->seg; |
| 4074 | (void)DESTROY_LOCK(&ms->mutex); /* destroy before unmapped */ |
| 4075 | while (sp != 0) { |
| 4076 | char* base = sp->base; |
| 4077 | size_t size = sp->size; |
| 4078 | flag_t flag = sp->sflags; |
| 4079 | (void)base; /* placate people compiling -Wunused-variable */ |
| 4080 | sp = sp->next; |
| 4081 | if ((flag & USE_MMAP_BIT) && !(flag & EXTERN_BIT) && |
| 4082 | CALL_MUNMAP(base, size) == 0) |
| 4083 | freed += size; |
| 4084 | } |
| 4085 | } |
| 4086 | else { |
| 4087 | USAGE_ERROR_ACTION(ms,ms); |
| 4088 | } |
| 4089 | return freed; |
| 4090 | } |
| 4091 | |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4092 | void mspace_get_address_and_size (mspace msp, char **addrp, size_t *sizep) |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4093 | { |
| 4094 | mstate ms; |
| 4095 | msegment *this_seg; |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4096 | |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4097 | ms = (mstate)msp; |
| 4098 | this_seg = &ms->seg; |
| 4099 | |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4100 | *addrp = this_seg->base; |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4101 | *sizep = this_seg->size; |
| 4102 | } |
| 4103 | |
| 4104 | int mspace_is_heap_object (mspace msp, void *p) |
| 4105 | { |
| 4106 | msegment *this_seg; |
| 4107 | char *pp, *base; |
| 4108 | mstate ms; |
| 4109 | |
| 4110 | ms = (mstate)msp; |
| 4111 | |
| 4112 | this_seg = &ms->seg; |
| 4113 | pp = (char *) p; |
| 4114 | |
| 4115 | while (this_seg) |
| 4116 | { |
| 4117 | base = this_seg->base; |
| 4118 | if (pp >= base && pp < (base + this_seg->size)) |
| 4119 | return 1; |
| 4120 | this_seg = this_seg->next; |
| 4121 | } |
Dave Barach | b76590a | 2018-08-23 11:23:00 -0400 | [diff] [blame] | 4122 | |
| 4123 | if (pp > ms->least_addr && pp <= ms->least_addr + ms->footprint) |
| 4124 | return 1; |
| 4125 | |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4126 | return 0; |
| 4127 | } |
| 4128 | |
| 4129 | void *mspace_least_addr (mspace msp) |
| 4130 | { |
| 4131 | mstate ms = (mstate) msp; |
| 4132 | return (void *) ms->least_addr; |
| 4133 | } |
| 4134 | |
| 4135 | void mspace_disable_expand (mspace msp) |
| 4136 | { |
| 4137 | mstate ms = (mstate)msp; |
| 4138 | |
| 4139 | disable_expand (ms); |
| 4140 | } |
| 4141 | |
| 4142 | int mspace_enable_disable_trace (mspace msp, int enable) |
| 4143 | { |
| 4144 | mstate ms = (mstate)msp; |
| 4145 | int was_enabled = 0; |
| 4146 | |
Dave Barach | ed2fe93 | 2018-07-19 12:29:45 -0400 | [diff] [blame] | 4147 | if (use_trace(ms)) |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4148 | was_enabled = 1; |
| 4149 | |
| 4150 | if (enable) |
| 4151 | enable_trace (ms); |
| 4152 | else |
| 4153 | disable_trace (ms); |
| 4154 | |
| 4155 | return (was_enabled); |
| 4156 | } |
| 4157 | |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4158 | int mspace_is_traced (mspace msp) |
| 4159 | { |
| 4160 | mstate ms = (mstate)msp; |
| 4161 | |
| 4162 | if (use_trace(ms)) |
| 4163 | return 1; |
| 4164 | return 0; |
| 4165 | } |
| 4166 | |
| 4167 | void* mspace_get_aligned (mspace msp, |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4168 | unsigned long n_user_data_bytes, |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4169 | unsigned long align, |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4170 | unsigned long align_offset) { |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4171 | char *rv; |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4172 | unsigned long searchp; |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4173 | unsigned *wwp; /* "where's Waldo" pointer */ |
| 4174 | mstate ms = (mstate)msp; |
| 4175 | |
| 4176 | /* |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4177 | * Allocate space for the "Where's Waldo?" pointer |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4178 | * the base of the dlmalloc object |
| 4179 | */ |
| 4180 | n_user_data_bytes += sizeof(unsigned); |
| 4181 | |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4182 | /* |
| 4183 | * Alignment requests less than the size of an mmx vector are ignored |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4184 | */ |
Florin Coras | f5dc9fb | 2019-04-16 11:27:54 -0700 | [diff] [blame] | 4185 | if (align < sizeof (uword)) { |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4186 | rv = mspace_malloc (msp, n_user_data_bytes); |
| 4187 | if (rv == 0) |
| 4188 | return rv; |
| 4189 | |
| 4190 | if (use_trace(ms)) { |
| 4191 | mchunkptr p = mem2chunk(rv); |
| 4192 | size_t psize = chunksize(p); |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4193 | |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4194 | mheap_get_trace ((unsigned long)rv + sizeof (unsigned), psize); |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4195 | } |
| 4196 | |
| 4197 | wwp = (unsigned *)rv; |
| 4198 | *wwp = 0; |
| 4199 | rv += sizeof (unsigned); |
| 4200 | |
| 4201 | return rv; |
| 4202 | } |
| 4203 | |
| 4204 | /* |
| 4205 | * Alignment requests greater than 4K must be at offset zero, |
| 4206 | * and must be freed using mspace_free_no_offset - or never freed - |
| 4207 | * since the "Where's Waldo?" pointer would waste too much space. |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4208 | * |
| 4209 | * Waldo is the address of the chunk of memory returned by mspace_malloc, |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4210 | * which we need later to call mspace_free... |
| 4211 | */ |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4212 | if (align > 4<<10 || align_offset == ~0UL) { |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4213 | n_user_data_bytes -= sizeof(unsigned); |
| 4214 | assert(align_offset == 0); |
| 4215 | rv = internal_memalign(ms, (size_t)align, n_user_data_bytes); |
Dave Barach | d67a428 | 2019-06-15 12:46:13 -0400 | [diff] [blame^] | 4216 | |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4217 | /* Trace the allocation */ |
| 4218 | if (rv && use_trace(ms)) { |
| 4219 | mchunkptr p = mem2chunk(rv); |
| 4220 | size_t psize = chunksize(p); |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4221 | mheap_get_trace ((unsigned long)rv, psize); |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4222 | } |
| 4223 | return rv; |
| 4224 | } |
| 4225 | |
| 4226 | align = clib_max (align, MALLOC_ALIGNMENT); |
| 4227 | align = max_pow2 (align); |
| 4228 | |
| 4229 | /* Correct align offset to be smaller than alignment. */ |
| 4230 | align_offset &= (align - 1); |
| 4231 | |
| 4232 | n_user_data_bytes += align; |
| 4233 | rv = mspace_malloc (msp, n_user_data_bytes); |
| 4234 | |
| 4235 | if (rv == 0) |
| 4236 | return rv; |
| 4237 | |
| 4238 | /* Honor the alignment request */ |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4239 | searchp = (unsigned long)(rv + sizeof (unsigned)); |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4240 | |
| 4241 | #if 0 /* this is the idea... */ |
| 4242 | while ((searchp + align_offset) % align) |
| 4243 | searchp++; |
| 4244 | #endif |
| 4245 | |
| 4246 | { |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4247 | unsigned long where_now, delta; |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4248 | |
| 4249 | where_now = (searchp + align_offset) % align; |
| 4250 | delta = align - where_now; |
| 4251 | |
| 4252 | searchp += delta; |
| 4253 | } |
| 4254 | |
| 4255 | wwp = (unsigned *)(searchp - sizeof(unsigned)); |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4256 | *wwp = (searchp - (((unsigned long) rv) + sizeof (*wwp))); |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4257 | assert (*wwp < align); |
| 4258 | |
| 4259 | if (use_trace(ms)) { |
| 4260 | mchunkptr p = mem2chunk(rv); |
| 4261 | size_t psize = chunksize(p); |
Wei CHEN | 5e282e9 | 2019-04-09 12:38:40 +0800 | [diff] [blame] | 4262 | mheap_get_trace (searchp, psize); |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4263 | } |
| 4264 | return (void *) searchp; |
| 4265 | } |
| 4266 | |
| 4267 | void mspace_put (mspace msp, void *p_arg) |
| 4268 | { |
| 4269 | char *object_header; |
| 4270 | unsigned *wwp; |
| 4271 | mstate ms = (mstate)msp; |
| 4272 | |
| 4273 | /* Find the object header delta */ |
| 4274 | wwp = (unsigned *)p_arg; |
| 4275 | wwp --; |
| 4276 | |
| 4277 | /* Recover the dlmalloc object pointer */ |
| 4278 | object_header = (char *)wwp; |
| 4279 | object_header -= *wwp; |
| 4280 | |
| 4281 | /* Tracing (if enabled) */ |
| 4282 | if (use_trace(ms)) |
| 4283 | { |
| 4284 | mchunkptr p = mem2chunk(object_header); |
| 4285 | size_t psize = chunksize(p); |
| 4286 | |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4287 | mheap_put_trace ((unsigned long)p_arg, psize); |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4288 | } |
| 4289 | |
Dave Barach | 1c7bf5d | 2018-07-31 10:39:30 -0400 | [diff] [blame] | 4290 | #if CLIB_DEBUG > 0 |
| 4291 | /* Poison the object */ |
| 4292 | { |
| 4293 | size_t psize = mspace_usable_size (object_header); |
| 4294 | memset (object_header, 0x13, psize); |
| 4295 | } |
| 4296 | #endif |
| 4297 | |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4298 | /* And free it... */ |
| 4299 | mspace_free (msp, object_header); |
| 4300 | } |
| 4301 | |
| 4302 | void mspace_put_no_offset (mspace msp, void *p_arg) |
| 4303 | { |
| 4304 | mstate ms = (mstate)msp; |
| 4305 | |
| 4306 | if (use_trace(ms)) |
| 4307 | { |
| 4308 | mchunkptr p = mem2chunk(p_arg); |
| 4309 | size_t psize = chunksize(p); |
| 4310 | |
David Johnson | d9818dd | 2018-12-14 14:53:41 -0500 | [diff] [blame] | 4311 | mheap_put_trace ((unsigned long)p_arg, psize); |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4312 | } |
| 4313 | mspace_free (msp, p_arg); |
| 4314 | } |
| 4315 | |
| 4316 | size_t mspace_usable_size_with_delta (const void *p) |
| 4317 | { |
| 4318 | size_t usable_size; |
| 4319 | char *object_header; |
| 4320 | unsigned *wwp; |
| 4321 | |
| 4322 | /* Find the object header delta */ |
| 4323 | wwp = (unsigned *)p; |
| 4324 | wwp --; |
| 4325 | |
| 4326 | /* Recover the dlmalloc object pointer */ |
| 4327 | object_header = (char *)wwp; |
| 4328 | object_header -= *wwp; |
| 4329 | |
| 4330 | usable_size = mspace_usable_size (object_header); |
| 4331 | /* account for the offset and the size of the offset... */ |
| 4332 | usable_size -= (*wwp + sizeof (*wwp)); |
| 4333 | return usable_size; |
| 4334 | } |
| 4335 | |
| 4336 | /* |
| 4337 | mspace versions of routines are near-clones of the global |
| 4338 | versions. This is not so nice but better than the alternatives. |
| 4339 | */ |
| 4340 | |
| 4341 | void* mspace_malloc(mspace msp, size_t bytes) { |
| 4342 | mstate ms = (mstate)msp; |
| 4343 | if (!ok_magic(ms)) { |
| 4344 | USAGE_ERROR_ACTION(ms,ms); |
| 4345 | return 0; |
| 4346 | } |
| 4347 | if (!PREACTION(ms)) { |
| 4348 | void* mem; |
| 4349 | size_t nb; |
| 4350 | if (bytes <= MAX_SMALL_REQUEST) { |
| 4351 | bindex_t idx; |
| 4352 | binmap_t smallbits; |
| 4353 | nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes); |
| 4354 | idx = small_index(nb); |
| 4355 | smallbits = ms->smallmap >> idx; |
| 4356 | |
| 4357 | if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */ |
| 4358 | mchunkptr b, p; |
| 4359 | idx += ~smallbits & 1; /* Uses next bin if idx empty */ |
| 4360 | b = smallbin_at(ms, idx); |
| 4361 | p = b->fd; |
| 4362 | assert(chunksize(p) == small_index2size(idx)); |
| 4363 | unlink_first_small_chunk(ms, b, p, idx); |
| 4364 | set_inuse_and_pinuse(ms, p, small_index2size(idx)); |
| 4365 | mem = chunk2mem(p); |
| 4366 | check_malloced_chunk(ms, mem, nb); |
| 4367 | goto postaction; |
| 4368 | } |
| 4369 | |
| 4370 | else if (nb > ms->dvsize) { |
| 4371 | if (smallbits != 0) { /* Use chunk in next nonempty smallbin */ |
| 4372 | mchunkptr b, p, r; |
| 4373 | size_t rsize; |
| 4374 | bindex_t i; |
| 4375 | binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx)); |
| 4376 | binmap_t leastbit = least_bit(leftbits); |
| 4377 | compute_bit2idx(leastbit, i); |
| 4378 | b = smallbin_at(ms, i); |
| 4379 | p = b->fd; |
| 4380 | assert(chunksize(p) == small_index2size(i)); |
| 4381 | unlink_first_small_chunk(ms, b, p, i); |
| 4382 | rsize = small_index2size(i) - nb; |
| 4383 | /* Fit here cannot be remainderless if 4byte sizes */ |
| 4384 | if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE) |
| 4385 | set_inuse_and_pinuse(ms, p, small_index2size(i)); |
| 4386 | else { |
| 4387 | set_size_and_pinuse_of_inuse_chunk(ms, p, nb); |
| 4388 | r = chunk_plus_offset(p, nb); |
| 4389 | set_size_and_pinuse_of_free_chunk(r, rsize); |
| 4390 | replace_dv(ms, r, rsize); |
| 4391 | } |
| 4392 | mem = chunk2mem(p); |
| 4393 | check_malloced_chunk(ms, mem, nb); |
| 4394 | goto postaction; |
| 4395 | } |
| 4396 | |
| 4397 | else if (ms->treemap != 0 && (mem = tmalloc_small(ms, nb)) != 0) { |
| 4398 | check_malloced_chunk(ms, mem, nb); |
| 4399 | goto postaction; |
| 4400 | } |
| 4401 | } |
| 4402 | } |
| 4403 | else if (bytes >= MAX_REQUEST) |
| 4404 | nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */ |
| 4405 | else { |
| 4406 | nb = pad_request(bytes); |
| 4407 | if (ms->treemap != 0 && (mem = tmalloc_large(ms, nb)) != 0) { |
| 4408 | check_malloced_chunk(ms, mem, nb); |
| 4409 | goto postaction; |
| 4410 | } |
| 4411 | } |
| 4412 | |
| 4413 | if (nb <= ms->dvsize) { |
| 4414 | size_t rsize = ms->dvsize - nb; |
| 4415 | mchunkptr p = ms->dv; |
| 4416 | if (rsize >= MIN_CHUNK_SIZE) { /* split dv */ |
| 4417 | mchunkptr r = ms->dv = chunk_plus_offset(p, nb); |
| 4418 | ms->dvsize = rsize; |
| 4419 | set_size_and_pinuse_of_free_chunk(r, rsize); |
| 4420 | set_size_and_pinuse_of_inuse_chunk(ms, p, nb); |
| 4421 | } |
| 4422 | else { /* exhaust dv */ |
| 4423 | size_t dvs = ms->dvsize; |
| 4424 | ms->dvsize = 0; |
| 4425 | ms->dv = 0; |
| 4426 | set_inuse_and_pinuse(ms, p, dvs); |
| 4427 | } |
| 4428 | mem = chunk2mem(p); |
| 4429 | check_malloced_chunk(ms, mem, nb); |
| 4430 | goto postaction; |
| 4431 | } |
| 4432 | |
| 4433 | else if (nb < ms->topsize) { /* Split top */ |
| 4434 | size_t rsize = ms->topsize -= nb; |
| 4435 | mchunkptr p = ms->top; |
| 4436 | mchunkptr r = ms->top = chunk_plus_offset(p, nb); |
| 4437 | r->head = rsize | PINUSE_BIT; |
| 4438 | set_size_and_pinuse_of_inuse_chunk(ms, p, nb); |
| 4439 | mem = chunk2mem(p); |
| 4440 | check_top_chunk(ms, ms->top); |
| 4441 | check_malloced_chunk(ms, mem, nb); |
| 4442 | goto postaction; |
| 4443 | } |
| 4444 | |
| 4445 | mem = sys_alloc(ms, nb); |
| 4446 | |
| 4447 | postaction: |
| 4448 | POSTACTION(ms); |
| 4449 | return mem; |
| 4450 | } |
| 4451 | |
| 4452 | return 0; |
| 4453 | } |
| 4454 | |
| 4455 | void mspace_free(mspace msp, void* mem) { |
| 4456 | if (mem != 0) { |
| 4457 | mchunkptr p = mem2chunk(mem); |
| 4458 | #if FOOTERS |
| 4459 | mstate fm = get_mstate_for(p); |
| 4460 | (void)msp; /* placate people compiling -Wunused */ |
| 4461 | #else /* FOOTERS */ |
| 4462 | mstate fm = (mstate)msp; |
| 4463 | #endif /* FOOTERS */ |
| 4464 | if (!ok_magic(fm)) { |
| 4465 | USAGE_ERROR_ACTION(fm, p); |
| 4466 | return; |
| 4467 | } |
| 4468 | if (!PREACTION(fm)) { |
| 4469 | check_inuse_chunk(fm, p); |
| 4470 | if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) { |
| 4471 | size_t psize = chunksize(p); |
| 4472 | mchunkptr next = chunk_plus_offset(p, psize); |
| 4473 | if (!pinuse(p)) { |
| 4474 | size_t prevsize = p->prev_foot; |
| 4475 | if (is_mmapped(p)) { |
| 4476 | psize += prevsize + MMAP_FOOT_PAD; |
| 4477 | if (CALL_MUNMAP((char*)p - prevsize, psize) == 0) |
| 4478 | fm->footprint -= psize; |
| 4479 | goto postaction; |
| 4480 | } |
| 4481 | else { |
| 4482 | mchunkptr prev = chunk_minus_offset(p, prevsize); |
| 4483 | psize += prevsize; |
| 4484 | p = prev; |
| 4485 | if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */ |
| 4486 | if (p != fm->dv) { |
| 4487 | unlink_chunk(fm, p, prevsize); |
| 4488 | } |
| 4489 | else if ((next->head & INUSE_BITS) == INUSE_BITS) { |
| 4490 | fm->dvsize = psize; |
| 4491 | set_free_with_pinuse(p, psize, next); |
| 4492 | goto postaction; |
| 4493 | } |
| 4494 | } |
| 4495 | else |
| 4496 | goto erroraction; |
| 4497 | } |
| 4498 | } |
| 4499 | |
| 4500 | if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) { |
| 4501 | if (!cinuse(next)) { /* consolidate forward */ |
| 4502 | if (next == fm->top) { |
| 4503 | size_t tsize = fm->topsize += psize; |
| 4504 | fm->top = p; |
| 4505 | p->head = tsize | PINUSE_BIT; |
| 4506 | if (p == fm->dv) { |
| 4507 | fm->dv = 0; |
| 4508 | fm->dvsize = 0; |
| 4509 | } |
| 4510 | if (should_trim(fm, tsize)) |
| 4511 | sys_trim(fm, 0); |
| 4512 | goto postaction; |
| 4513 | } |
| 4514 | else if (next == fm->dv) { |
| 4515 | size_t dsize = fm->dvsize += psize; |
| 4516 | fm->dv = p; |
| 4517 | set_size_and_pinuse_of_free_chunk(p, dsize); |
| 4518 | goto postaction; |
| 4519 | } |
| 4520 | else { |
| 4521 | size_t nsize = chunksize(next); |
| 4522 | psize += nsize; |
| 4523 | unlink_chunk(fm, next, nsize); |
| 4524 | set_size_and_pinuse_of_free_chunk(p, psize); |
| 4525 | if (p == fm->dv) { |
| 4526 | fm->dvsize = psize; |
| 4527 | goto postaction; |
| 4528 | } |
| 4529 | } |
| 4530 | } |
| 4531 | else |
| 4532 | set_free_with_pinuse(p, psize, next); |
| 4533 | |
| 4534 | if (is_small(psize)) { |
| 4535 | insert_small_chunk(fm, p, psize); |
| 4536 | check_free_chunk(fm, p); |
| 4537 | } |
| 4538 | else { |
| 4539 | tchunkptr tp = (tchunkptr)p; |
| 4540 | insert_large_chunk(fm, tp, psize); |
| 4541 | check_free_chunk(fm, p); |
| 4542 | if (--fm->release_checks == 0) |
| 4543 | release_unused_segments(fm); |
| 4544 | } |
| 4545 | goto postaction; |
| 4546 | } |
| 4547 | } |
| 4548 | erroraction: |
| 4549 | USAGE_ERROR_ACTION(fm, p); |
| 4550 | postaction: |
| 4551 | POSTACTION(fm); |
| 4552 | } |
| 4553 | } |
| 4554 | } |
| 4555 | |
| 4556 | void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size) { |
| 4557 | void* mem; |
| 4558 | size_t req = 0; |
| 4559 | mstate ms = (mstate)msp; |
| 4560 | if (!ok_magic(ms)) { |
| 4561 | USAGE_ERROR_ACTION(ms,ms); |
| 4562 | return 0; |
| 4563 | } |
| 4564 | if (n_elements != 0) { |
| 4565 | req = n_elements * elem_size; |
| 4566 | if (((n_elements | elem_size) & ~(size_t)0xffff) && |
| 4567 | (req / n_elements != elem_size)) |
| 4568 | req = MAX_SIZE_T; /* force downstream failure on overflow */ |
| 4569 | } |
| 4570 | mem = internal_malloc(ms, req); |
| 4571 | if (mem != 0 && calloc_must_clear(mem2chunk(mem))) |
| 4572 | memset(mem, 0, req); |
| 4573 | return mem; |
| 4574 | } |
| 4575 | |
| 4576 | void* mspace_realloc(mspace msp, void* oldmem, size_t bytes) { |
| 4577 | void* mem = 0; |
| 4578 | if (oldmem == 0) { |
| 4579 | mem = mspace_malloc(msp, bytes); |
| 4580 | } |
| 4581 | else if (bytes >= MAX_REQUEST) { |
| 4582 | MALLOC_FAILURE_ACTION; |
| 4583 | } |
| 4584 | #ifdef REALLOC_ZERO_BYTES_FREES |
| 4585 | else if (bytes == 0) { |
| 4586 | mspace_free(msp, oldmem); |
| 4587 | } |
| 4588 | #endif /* REALLOC_ZERO_BYTES_FREES */ |
| 4589 | else { |
| 4590 | size_t nb = request2size(bytes); |
| 4591 | mchunkptr oldp = mem2chunk(oldmem); |
| 4592 | #if ! FOOTERS |
| 4593 | mstate m = (mstate)msp; |
| 4594 | #else /* FOOTERS */ |
| 4595 | mstate m = get_mstate_for(oldp); |
| 4596 | if (!ok_magic(m)) { |
| 4597 | USAGE_ERROR_ACTION(m, oldmem); |
| 4598 | return 0; |
| 4599 | } |
| 4600 | #endif /* FOOTERS */ |
| 4601 | if (!PREACTION(m)) { |
| 4602 | mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1); |
| 4603 | POSTACTION(m); |
| 4604 | if (newp != 0) { |
| 4605 | check_inuse_chunk(m, newp); |
| 4606 | mem = chunk2mem(newp); |
| 4607 | } |
| 4608 | else { |
| 4609 | mem = mspace_malloc(m, bytes); |
| 4610 | if (mem != 0) { |
| 4611 | size_t oc = chunksize(oldp) - overhead_for(oldp); |
| 4612 | memcpy(mem, oldmem, (oc < bytes)? oc : bytes); |
| 4613 | mspace_free(m, oldmem); |
| 4614 | } |
| 4615 | } |
| 4616 | } |
| 4617 | } |
| 4618 | return mem; |
| 4619 | } |
| 4620 | |
| 4621 | void* mspace_realloc_in_place(mspace msp, void* oldmem, size_t bytes) { |
| 4622 | void* mem = 0; |
| 4623 | if (oldmem != 0) { |
| 4624 | if (bytes >= MAX_REQUEST) { |
| 4625 | MALLOC_FAILURE_ACTION; |
| 4626 | } |
| 4627 | else { |
| 4628 | size_t nb = request2size(bytes); |
| 4629 | mchunkptr oldp = mem2chunk(oldmem); |
| 4630 | #if ! FOOTERS |
| 4631 | mstate m = (mstate)msp; |
| 4632 | #else /* FOOTERS */ |
| 4633 | mstate m = get_mstate_for(oldp); |
| 4634 | (void)msp; /* placate people compiling -Wunused */ |
| 4635 | if (!ok_magic(m)) { |
| 4636 | USAGE_ERROR_ACTION(m, oldmem); |
| 4637 | return 0; |
| 4638 | } |
| 4639 | #endif /* FOOTERS */ |
| 4640 | if (!PREACTION(m)) { |
| 4641 | mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0); |
| 4642 | POSTACTION(m); |
| 4643 | if (newp == oldp) { |
| 4644 | check_inuse_chunk(m, newp); |
| 4645 | mem = oldmem; |
| 4646 | } |
| 4647 | } |
| 4648 | } |
| 4649 | } |
| 4650 | return mem; |
| 4651 | } |
| 4652 | |
| 4653 | void* mspace_memalign(mspace msp, size_t alignment, size_t bytes) { |
| 4654 | mstate ms = (mstate)msp; |
| 4655 | if (!ok_magic(ms)) { |
| 4656 | USAGE_ERROR_ACTION(ms,ms); |
| 4657 | return 0; |
| 4658 | } |
| 4659 | if (alignment <= MALLOC_ALIGNMENT) |
| 4660 | return mspace_malloc(msp, bytes); |
| 4661 | return internal_memalign(ms, alignment, bytes); |
| 4662 | } |
| 4663 | |
| 4664 | void** mspace_independent_calloc(mspace msp, size_t n_elements, |
| 4665 | size_t elem_size, void* chunks[]) { |
| 4666 | size_t sz = elem_size; /* serves as 1-element array */ |
| 4667 | mstate ms = (mstate)msp; |
| 4668 | if (!ok_magic(ms)) { |
| 4669 | USAGE_ERROR_ACTION(ms,ms); |
| 4670 | return 0; |
| 4671 | } |
| 4672 | return ialloc(ms, n_elements, &sz, 3, chunks); |
| 4673 | } |
| 4674 | |
| 4675 | void** mspace_independent_comalloc(mspace msp, size_t n_elements, |
| 4676 | size_t sizes[], void* chunks[]) { |
| 4677 | mstate ms = (mstate)msp; |
| 4678 | if (!ok_magic(ms)) { |
| 4679 | USAGE_ERROR_ACTION(ms,ms); |
| 4680 | return 0; |
| 4681 | } |
| 4682 | return ialloc(ms, n_elements, sizes, 0, chunks); |
| 4683 | } |
| 4684 | |
| 4685 | size_t mspace_bulk_free(mspace msp, void* array[], size_t nelem) { |
| 4686 | return internal_bulk_free((mstate)msp, array, nelem); |
| 4687 | } |
| 4688 | |
| 4689 | #if MALLOC_INSPECT_ALL |
| 4690 | void mspace_inspect_all(mspace msp, |
| 4691 | void(*handler)(void *start, |
| 4692 | void *end, |
| 4693 | size_t used_bytes, |
| 4694 | void* callback_arg), |
| 4695 | void* arg) { |
| 4696 | mstate ms = (mstate)msp; |
| 4697 | if (ok_magic(ms)) { |
| 4698 | if (!PREACTION(ms)) { |
| 4699 | internal_inspect_all(ms, handler, arg); |
| 4700 | POSTACTION(ms); |
| 4701 | } |
| 4702 | } |
| 4703 | else { |
| 4704 | USAGE_ERROR_ACTION(ms,ms); |
| 4705 | } |
| 4706 | } |
| 4707 | #endif /* MALLOC_INSPECT_ALL */ |
| 4708 | |
| 4709 | int mspace_trim(mspace msp, size_t pad) { |
| 4710 | int result = 0; |
| 4711 | mstate ms = (mstate)msp; |
| 4712 | if (ok_magic(ms)) { |
| 4713 | if (!PREACTION(ms)) { |
| 4714 | result = sys_trim(ms, pad); |
| 4715 | POSTACTION(ms); |
| 4716 | } |
| 4717 | } |
| 4718 | else { |
| 4719 | USAGE_ERROR_ACTION(ms,ms); |
| 4720 | } |
| 4721 | return result; |
| 4722 | } |
| 4723 | |
| 4724 | #if !NO_MALLOC_STATS |
| 4725 | void mspace_malloc_stats(mspace msp) { |
| 4726 | mstate ms = (mstate)msp; |
| 4727 | if (ok_magic(ms)) { |
| 4728 | internal_malloc_stats(ms); |
| 4729 | } |
| 4730 | else { |
| 4731 | USAGE_ERROR_ACTION(ms,ms); |
| 4732 | } |
| 4733 | } |
| 4734 | #endif /* NO_MALLOC_STATS */ |
| 4735 | |
| 4736 | size_t mspace_footprint(mspace msp) { |
| 4737 | size_t result = 0; |
| 4738 | mstate ms = (mstate)msp; |
| 4739 | if (ok_magic(ms)) { |
| 4740 | result = ms->footprint; |
| 4741 | } |
| 4742 | else { |
| 4743 | USAGE_ERROR_ACTION(ms,ms); |
| 4744 | } |
| 4745 | return result; |
| 4746 | } |
| 4747 | |
| 4748 | size_t mspace_max_footprint(mspace msp) { |
| 4749 | size_t result = 0; |
| 4750 | mstate ms = (mstate)msp; |
| 4751 | if (ok_magic(ms)) { |
| 4752 | result = ms->max_footprint; |
| 4753 | } |
| 4754 | else { |
| 4755 | USAGE_ERROR_ACTION(ms,ms); |
| 4756 | } |
| 4757 | return result; |
| 4758 | } |
| 4759 | |
| 4760 | size_t mspace_footprint_limit(mspace msp) { |
| 4761 | size_t result = 0; |
| 4762 | mstate ms = (mstate)msp; |
| 4763 | if (ok_magic(ms)) { |
| 4764 | size_t maf = ms->footprint_limit; |
| 4765 | result = (maf == 0) ? MAX_SIZE_T : maf; |
| 4766 | } |
| 4767 | else { |
| 4768 | USAGE_ERROR_ACTION(ms,ms); |
| 4769 | } |
| 4770 | return result; |
| 4771 | } |
| 4772 | |
| 4773 | size_t mspace_set_footprint_limit(mspace msp, size_t bytes) { |
| 4774 | size_t result = 0; |
| 4775 | mstate ms = (mstate)msp; |
| 4776 | if (ok_magic(ms)) { |
| 4777 | if (bytes == 0) |
| 4778 | result = granularity_align(1); /* Use minimal size */ |
| 4779 | if (bytes == MAX_SIZE_T) |
| 4780 | result = 0; /* disable */ |
| 4781 | else |
| 4782 | result = granularity_align(bytes); |
| 4783 | ms->footprint_limit = result; |
| 4784 | } |
| 4785 | else { |
| 4786 | USAGE_ERROR_ACTION(ms,ms); |
| 4787 | } |
| 4788 | return result; |
| 4789 | } |
| 4790 | |
| 4791 | #if !NO_MALLINFO |
Dave Barach | af7dd5b | 2018-08-23 17:08:44 -0400 | [diff] [blame] | 4792 | struct dlmallinfo mspace_mallinfo(mspace msp) { |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 4793 | mstate ms = (mstate)msp; |
| 4794 | if (!ok_magic(ms)) { |
| 4795 | USAGE_ERROR_ACTION(ms,ms); |
| 4796 | } |
| 4797 | return internal_mallinfo(ms); |
| 4798 | } |
| 4799 | #endif /* NO_MALLINFO */ |
| 4800 | |
| 4801 | size_t mspace_usable_size(const void* mem) { |
| 4802 | if (mem != 0) { |
| 4803 | mchunkptr p = mem2chunk(mem); |
| 4804 | if (is_inuse(p)) |
| 4805 | return chunksize(p) - overhead_for(p); |
| 4806 | } |
| 4807 | return 0; |
| 4808 | } |
| 4809 | |
| 4810 | int mspace_mallopt(int param_number, int value) { |
| 4811 | return change_mparam(param_number, value); |
| 4812 | } |
| 4813 | |
| 4814 | #endif /* MSPACES */ |
| 4815 | |
| 4816 | |
| 4817 | /* -------------------- Alternative MORECORE functions ------------------- */ |
| 4818 | |
| 4819 | /* |
| 4820 | Guidelines for creating a custom version of MORECORE: |
| 4821 | |
| 4822 | * For best performance, MORECORE should allocate in multiples of pagesize. |
| 4823 | * MORECORE may allocate more memory than requested. (Or even less, |
| 4824 | but this will usually result in a malloc failure.) |
| 4825 | * MORECORE must not allocate memory when given argument zero, but |
| 4826 | instead return one past the end address of memory from previous |
| 4827 | nonzero call. |
| 4828 | * For best performance, consecutive calls to MORECORE with positive |
| 4829 | arguments should return increasing addresses, indicating that |
| 4830 | space has been contiguously extended. |
| 4831 | * Even though consecutive calls to MORECORE need not return contiguous |
| 4832 | addresses, it must be OK for malloc'ed chunks to span multiple |
| 4833 | regions in those cases where they do happen to be contiguous. |
| 4834 | * MORECORE need not handle negative arguments -- it may instead |
| 4835 | just return MFAIL when given negative arguments. |
| 4836 | Negative arguments are always multiples of pagesize. MORECORE |
| 4837 | must not misinterpret negative args as large positive unsigned |
| 4838 | args. You can suppress all such calls from even occurring by defining |
| 4839 | MORECORE_CANNOT_TRIM, |
| 4840 | |
| 4841 | As an example alternative MORECORE, here is a custom allocator |
| 4842 | kindly contributed for pre-OSX macOS. It uses virtually but not |
| 4843 | necessarily physically contiguous non-paged memory (locked in, |
| 4844 | present and won't get swapped out). You can use it by uncommenting |
| 4845 | this section, adding some #includes, and setting up the appropriate |
| 4846 | defines above: |
| 4847 | |
| 4848 | #define MORECORE osMoreCore |
| 4849 | |
| 4850 | There is also a shutdown routine that should somehow be called for |
| 4851 | cleanup upon program exit. |
| 4852 | |
| 4853 | #define MAX_POOL_ENTRIES 100 |
| 4854 | #define MINIMUM_MORECORE_SIZE (64 * 1024U) |
| 4855 | static int next_os_pool; |
| 4856 | void *our_os_pools[MAX_POOL_ENTRIES]; |
| 4857 | |
| 4858 | void *osMoreCore(int size) |
| 4859 | { |
| 4860 | void *ptr = 0; |
| 4861 | static void *sbrk_top = 0; |
| 4862 | |
| 4863 | if (size > 0) |
| 4864 | { |
| 4865 | if (size < MINIMUM_MORECORE_SIZE) |
| 4866 | size = MINIMUM_MORECORE_SIZE; |
| 4867 | if (CurrentExecutionLevel() == kTaskLevel) |
| 4868 | ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0); |
| 4869 | if (ptr == 0) |
| 4870 | { |
| 4871 | return (void *) MFAIL; |
| 4872 | } |
| 4873 | // save ptrs so they can be freed during cleanup |
| 4874 | our_os_pools[next_os_pool] = ptr; |
| 4875 | next_os_pool++; |
| 4876 | ptr = (void *) ((((size_t) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK); |
| 4877 | sbrk_top = (char *) ptr + size; |
| 4878 | return ptr; |
| 4879 | } |
| 4880 | else if (size < 0) |
| 4881 | { |
| 4882 | // we don't currently support shrink behavior |
| 4883 | return (void *) MFAIL; |
| 4884 | } |
| 4885 | else |
| 4886 | { |
| 4887 | return sbrk_top; |
| 4888 | } |
| 4889 | } |
| 4890 | |
| 4891 | // cleanup any allocated memory pools |
| 4892 | // called as last thing before shutting down driver |
| 4893 | |
| 4894 | void osCleanupMem(void) |
| 4895 | { |
| 4896 | void **ptr; |
| 4897 | |
| 4898 | for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++) |
| 4899 | if (*ptr) |
| 4900 | { |
| 4901 | PoolDeallocate(*ptr); |
| 4902 | *ptr = 0; |
| 4903 | } |
| 4904 | } |
| 4905 | |
| 4906 | */ |
| 4907 | |
| 4908 | |
| 4909 | /* ----------------------------------------------------------------------- |
| 4910 | History: |
| 4911 | v2.8.6 Wed Aug 29 06:57:58 2012 Doug Lea |
| 4912 | * fix bad comparison in dlposix_memalign |
| 4913 | * don't reuse adjusted asize in sys_alloc |
| 4914 | * add LOCK_AT_FORK -- thanks to Kirill Artamonov for the suggestion |
| 4915 | * reduce compiler warnings -- thanks to all who reported/suggested these |
| 4916 | |
| 4917 | v2.8.5 Sun May 22 10:26:02 2011 Doug Lea (dl at gee) |
| 4918 | * Always perform unlink checks unless INSECURE |
| 4919 | * Add posix_memalign. |
| 4920 | * Improve realloc to expand in more cases; expose realloc_in_place. |
| 4921 | Thanks to Peter Buhr for the suggestion. |
| 4922 | * Add footprint_limit, inspect_all, bulk_free. Thanks |
| 4923 | to Barry Hayes and others for the suggestions. |
| 4924 | * Internal refactorings to avoid calls while holding locks |
| 4925 | * Use non-reentrant locks by default. Thanks to Roland McGrath |
| 4926 | for the suggestion. |
| 4927 | * Small fixes to mspace_destroy, reset_on_error. |
| 4928 | * Various configuration extensions/changes. Thanks |
| 4929 | to all who contributed these. |
| 4930 | |
| 4931 | V2.8.4a Thu Apr 28 14:39:43 2011 (dl at gee.cs.oswego.edu) |
| 4932 | * Update Creative Commons URL |
| 4933 | |
| 4934 | V2.8.4 Wed May 27 09:56:23 2009 Doug Lea (dl at gee) |
| 4935 | * Use zeros instead of prev foot for is_mmapped |
| 4936 | * Add mspace_track_large_chunks; thanks to Jean Brouwers |
| 4937 | * Fix set_inuse in internal_realloc; thanks to Jean Brouwers |
| 4938 | * Fix insufficient sys_alloc padding when using 16byte alignment |
| 4939 | * Fix bad error check in mspace_footprint |
| 4940 | * Adaptations for ptmalloc; thanks to Wolfram Gloger. |
| 4941 | * Reentrant spin locks; thanks to Earl Chew and others |
| 4942 | * Win32 improvements; thanks to Niall Douglas and Earl Chew |
| 4943 | * Add NO_SEGMENT_TRAVERSAL and MAX_RELEASE_CHECK_RATE options |
| 4944 | * Extension hook in malloc_state |
| 4945 | * Various small adjustments to reduce warnings on some compilers |
| 4946 | * Various configuration extensions/changes for more platforms. Thanks |
| 4947 | to all who contributed these. |
| 4948 | |
| 4949 | V2.8.3 Thu Sep 22 11:16:32 2005 Doug Lea (dl at gee) |
| 4950 | * Add max_footprint functions |
| 4951 | * Ensure all appropriate literals are size_t |
| 4952 | * Fix conditional compilation problem for some #define settings |
| 4953 | * Avoid concatenating segments with the one provided |
| 4954 | in create_mspace_with_base |
| 4955 | * Rename some variables to avoid compiler shadowing warnings |
| 4956 | * Use explicit lock initialization. |
| 4957 | * Better handling of sbrk interference. |
| 4958 | * Simplify and fix segment insertion, trimming and mspace_destroy |
| 4959 | * Reinstate REALLOC_ZERO_BYTES_FREES option from 2.7.x |
| 4960 | * Thanks especially to Dennis Flanagan for help on these. |
| 4961 | |
| 4962 | V2.8.2 Sun Jun 12 16:01:10 2005 Doug Lea (dl at gee) |
| 4963 | * Fix memalign brace error. |
| 4964 | |
| 4965 | V2.8.1 Wed Jun 8 16:11:46 2005 Doug Lea (dl at gee) |
| 4966 | * Fix improper #endif nesting in C++ |
| 4967 | * Add explicit casts needed for C++ |
| 4968 | |
| 4969 | V2.8.0 Mon May 30 14:09:02 2005 Doug Lea (dl at gee) |
| 4970 | * Use trees for large bins |
| 4971 | * Support mspaces |
| 4972 | * Use segments to unify sbrk-based and mmap-based system allocation, |
| 4973 | removing need for emulation on most platforms without sbrk. |
| 4974 | * Default safety checks |
| 4975 | * Optional footer checks. Thanks to William Robertson for the idea. |
| 4976 | * Internal code refactoring |
| 4977 | * Incorporate suggestions and platform-specific changes. |
| 4978 | Thanks to Dennis Flanagan, Colin Plumb, Niall Douglas, |
| 4979 | Aaron Bachmann, Emery Berger, and others. |
| 4980 | * Speed up non-fastbin processing enough to remove fastbins. |
| 4981 | * Remove useless cfree() to avoid conflicts with other apps. |
| 4982 | * Remove internal memcpy, memset. Compilers handle builtins better. |
| 4983 | * Remove some options that no one ever used and rename others. |
| 4984 | |
| 4985 | V2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee) |
| 4986 | * Fix malloc_state bitmap array misdeclaration |
| 4987 | |
| 4988 | V2.7.1 Thu Jul 25 10:58:03 2002 Doug Lea (dl at gee) |
| 4989 | * Allow tuning of FIRST_SORTED_BIN_SIZE |
| 4990 | * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte. |
| 4991 | * Better detection and support for non-contiguousness of MORECORE. |
| 4992 | Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger |
| 4993 | * Bypass most of malloc if no frees. Thanks To Emery Berger. |
| 4994 | * Fix freeing of old top non-contiguous chunk im sysmalloc. |
| 4995 | * Raised default trim and map thresholds to 256K. |
| 4996 | * Fix mmap-related #defines. Thanks to Lubos Lunak. |
| 4997 | * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield. |
| 4998 | * Branch-free bin calculation |
| 4999 | * Default trim and mmap thresholds now 256K. |
| 5000 | |
| 5001 | V2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee) |
| 5002 | * Introduce independent_comalloc and independent_calloc. |
| 5003 | Thanks to Michael Pachos for motivation and help. |
| 5004 | * Make optional .h file available |
| 5005 | * Allow > 2GB requests on 32bit systems. |
| 5006 | * new WIN32 sbrk, mmap, munmap, lock code from <Walter@GeNeSys-e.de>. |
| 5007 | Thanks also to Andreas Mueller <a.mueller at paradatec.de>, |
| 5008 | and Anonymous. |
| 5009 | * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for |
| 5010 | helping test this.) |
| 5011 | * memalign: check alignment arg |
| 5012 | * realloc: don't try to shift chunks backwards, since this |
| 5013 | leads to more fragmentation in some programs and doesn't |
| 5014 | seem to help in any others. |
| 5015 | * Collect all cases in malloc requiring system memory into sysmalloc |
| 5016 | * Use mmap as backup to sbrk |
| 5017 | * Place all internal state in malloc_state |
| 5018 | * Introduce fastbins (although similar to 2.5.1) |
| 5019 | * Many minor tunings and cosmetic improvements |
| 5020 | * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK |
| 5021 | * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS |
| 5022 | Thanks to Tony E. Bennett <tbennett@nvidia.com> and others. |
| 5023 | * Include errno.h to support default failure action. |
| 5024 | |
| 5025 | V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee) |
| 5026 | * return null for negative arguments |
| 5027 | * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com> |
| 5028 | * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h' |
| 5029 | (e.g. WIN32 platforms) |
| 5030 | * Cleanup header file inclusion for WIN32 platforms |
| 5031 | * Cleanup code to avoid Microsoft Visual C++ compiler complaints |
| 5032 | * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing |
| 5033 | memory allocation routines |
| 5034 | * Set 'malloc_getpagesize' for WIN32 platforms (needs more work) |
| 5035 | * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to |
| 5036 | usage of 'assert' in non-WIN32 code |
| 5037 | * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to |
| 5038 | avoid infinite loop |
| 5039 | * Always call 'fREe()' rather than 'free()' |
| 5040 | |
| 5041 | V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee) |
| 5042 | * Fixed ordering problem with boundary-stamping |
| 5043 | |
| 5044 | V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee) |
| 5045 | * Added pvalloc, as recommended by H.J. Liu |
| 5046 | * Added 64bit pointer support mainly from Wolfram Gloger |
| 5047 | * Added anonymously donated WIN32 sbrk emulation |
| 5048 | * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen |
| 5049 | * malloc_extend_top: fix mask error that caused wastage after |
| 5050 | foreign sbrks |
| 5051 | * Add linux mremap support code from HJ Liu |
| 5052 | |
| 5053 | V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee) |
| 5054 | * Integrated most documentation with the code. |
| 5055 | * Add support for mmap, with help from |
| 5056 | Wolfram Gloger (Gloger@lrz.uni-muenchen.de). |
| 5057 | * Use last_remainder in more cases. |
| 5058 | * Pack bins using idea from colin@nyx10.cs.du.edu |
Paul Vinciguerra | ec11b13 | 2018-09-24 05:25:00 -0700 | [diff] [blame] | 5059 | * Use ordered bins instead of best-fit threshold |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 5060 | * Eliminate block-local decls to simplify tracing and debugging. |
| 5061 | * Support another case of realloc via move into top |
Paul Vinciguerra | ec11b13 | 2018-09-24 05:25:00 -0700 | [diff] [blame] | 5062 | * Fix error occurring when initial sbrk_base not word-aligned. |
Dave Barach | 6a5adc3 | 2018-07-04 10:56:23 -0400 | [diff] [blame] | 5063 | * Rely on page size for units instead of SBRK_UNIT to |
| 5064 | avoid surprises about sbrk alignment conventions. |
| 5065 | * Add mallinfo, mallopt. Thanks to Raymond Nijssen |
| 5066 | (raymond@es.ele.tue.nl) for the suggestion. |
| 5067 | * Add `pad' argument to malloc_trim and top_pad mallopt parameter. |
| 5068 | * More precautions for cases where other routines call sbrk, |
| 5069 | courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de). |
| 5070 | * Added macros etc., allowing use in linux libc from |
| 5071 | H.J. Lu (hjl@gnu.ai.mit.edu) |
| 5072 | * Inverted this history list |
| 5073 | |
| 5074 | V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee) |
| 5075 | * Re-tuned and fixed to behave more nicely with V2.6.0 changes. |
| 5076 | * Removed all preallocation code since under current scheme |
| 5077 | the work required to undo bad preallocations exceeds |
| 5078 | the work saved in good cases for most test programs. |
| 5079 | * No longer use return list or unconsolidated bins since |
| 5080 | no scheme using them consistently outperforms those that don't |
| 5081 | given above changes. |
| 5082 | * Use best fit for very large chunks to prevent some worst-cases. |
| 5083 | * Added some support for debugging |
| 5084 | |
| 5085 | V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee) |
| 5086 | * Removed footers when chunks are in use. Thanks to |
| 5087 | Paul Wilson (wilson@cs.texas.edu) for the suggestion. |
| 5088 | |
| 5089 | V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee) |
| 5090 | * Added malloc_trim, with help from Wolfram Gloger |
| 5091 | (wmglo@Dent.MED.Uni-Muenchen.DE). |
| 5092 | |
| 5093 | V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g) |
| 5094 | |
| 5095 | V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g) |
| 5096 | * realloc: try to expand in both directions |
| 5097 | * malloc: swap order of clean-bin strategy; |
| 5098 | * realloc: only conditionally expand backwards |
| 5099 | * Try not to scavenge used bins |
| 5100 | * Use bin counts as a guide to preallocation |
| 5101 | * Occasionally bin return list chunks in first scan |
| 5102 | * Add a few optimizations from colin@nyx10.cs.du.edu |
| 5103 | |
| 5104 | V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g) |
| 5105 | * faster bin computation & slightly different binning |
| 5106 | * merged all consolidations to one part of malloc proper |
| 5107 | (eliminating old malloc_find_space & malloc_clean_bin) |
| 5108 | * Scan 2 returns chunks (not just 1) |
| 5109 | * Propagate failure in realloc if malloc returns 0 |
| 5110 | * Add stuff to allow compilation on non-ANSI compilers |
| 5111 | from kpv@research.att.com |
| 5112 | |
| 5113 | V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu) |
| 5114 | * removed potential for odd address access in prev_chunk |
| 5115 | * removed dependency on getpagesize.h |
| 5116 | * misc cosmetics and a bit more internal documentation |
| 5117 | * anticosmetics: mangled names in macros to evade debugger strangeness |
| 5118 | * tested on sparc, hp-700, dec-mips, rs6000 |
| 5119 | with gcc & native cc (hp, dec only) allowing |
| 5120 | Detlefs & Zorn comparison study (in SIGPLAN Notices.) |
| 5121 | |
| 5122 | Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu) |
| 5123 | * Based loosely on libg++-1.2X malloc. (It retains some of the overall |
| 5124 | structure of old version, but most details differ.) |
| 5125 | |
| 5126 | */ |