| /* vi: set sw=4 ts=4: */ |
| /* |
| * Utility routines. |
| * |
| * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> |
| * Copyright (C) 2006 Rob Landley |
| * Copyright (C) 2006 Denys Vlasenko |
| * |
| * Licensed under GPL version 2, see file LICENSE in this tarball for details. |
| */ |
| |
| /* We need to have separate xfuncs.c and xfuncs_printf.c because |
| * with current linkers, even with section garbage collection, |
| * if *.o module references any of XXXprintf functions, you pull in |
| * entire printf machinery. Even if you do not use the function |
| * which uses XXXprintf. |
| * |
| * xfuncs.c contains functions (not necessarily xfuncs) |
| * which do not pull in printf, directly or indirectly. |
| * xfunc_printf.c contains those which do. |
| */ |
| |
| #include "libbb.h" |
| |
| |
| /* All the functions starting with "x" call bb_error_msg_and_die() if they |
| * fail, so callers never need to check for errors. If it returned, it |
| * succeeded. */ |
| |
| #ifndef DMALLOC |
| /* dmalloc provides variants of these that do abort() on failure. |
| * Since dmalloc's prototypes overwrite the impls here as they are |
| * included after these prototypes in libbb.h, all is well. |
| */ |
| // Warn if we can't allocate size bytes of memory. |
| void* FAST_FUNC malloc_or_warn(size_t size) |
| { |
| void *ptr = malloc(size); |
| if (ptr == NULL && size != 0) |
| bb_error_msg(bb_msg_memory_exhausted); |
| return ptr; |
| } |
| |
| // Die if we can't allocate size bytes of memory. |
| void* FAST_FUNC xmalloc(size_t size) |
| { |
| void *ptr = malloc(size); |
| if (ptr == NULL && size != 0) |
| bb_error_msg_and_die(bb_msg_memory_exhausted); |
| return ptr; |
| } |
| |
| // Die if we can't resize previously allocated memory. (This returns a pointer |
| // to the new memory, which may or may not be the same as the old memory. |
| // It'll copy the contents to a new chunk and free the old one if necessary.) |
| void* FAST_FUNC xrealloc(void *ptr, size_t size) |
| { |
| ptr = realloc(ptr, size); |
| if (ptr == NULL && size != 0) |
| bb_error_msg_and_die(bb_msg_memory_exhausted); |
| return ptr; |
| } |
| #endif /* DMALLOC */ |
| |
| // Die if we can't allocate and zero size bytes of memory. |
| void* FAST_FUNC xzalloc(size_t size) |
| { |
| void *ptr = xmalloc(size); |
| memset(ptr, 0, size); |
| return ptr; |
| } |
| |
| // Die if we can't copy a string to freshly allocated memory. |
| char* FAST_FUNC xstrdup(const char *s) |
| { |
| char *t; |
| |
| if (s == NULL) |
| return NULL; |
| |
| t = strdup(s); |
| |
| if (t == NULL) |
| bb_error_msg_and_die(bb_msg_memory_exhausted); |
| |
| return t; |
| } |
| |
| // Die if we can't allocate n+1 bytes (space for the null terminator) and copy |
| // the (possibly truncated to length n) string into it. |
| char* FAST_FUNC xstrndup(const char *s, int n) |
| { |
| int m; |
| char *t; |
| |
| if (ENABLE_DEBUG && s == NULL) |
| bb_error_msg_and_die("xstrndup bug"); |
| |
| /* We can just xmalloc(n+1) and strncpy into it, */ |
| /* but think about xstrndup("abc", 10000) wastage! */ |
| m = n; |
| t = (char*) s; |
| while (m) { |
| if (!*t) break; |
| m--; |
| t++; |
| } |
| n -= m; |
| t = xmalloc(n + 1); |
| t[n] = '\0'; |
| |
| return memcpy(t, s, n); |
| } |
| |
| // Die if we can't open a file and return a FILE* to it. |
| // Notice we haven't got xfread(), This is for use with fscanf() and friends. |
| FILE* FAST_FUNC xfopen(const char *path, const char *mode) |
| { |
| FILE *fp = fopen(path, mode); |
| if (fp == NULL) |
| bb_perror_msg_and_die("can't open '%s'", path); |
| return fp; |
| } |
| |
| // Die if we can't open a file and return a fd. |
| int FAST_FUNC xopen3(const char *pathname, int flags, int mode) |
| { |
| int ret; |
| |
| ret = open(pathname, flags, mode); |
| if (ret < 0) { |
| bb_perror_msg_and_die("can't open '%s'", pathname); |
| } |
| return ret; |
| } |
| |
| // Die if we can't open an existing file and return a fd. |
| int FAST_FUNC xopen(const char *pathname, int flags) |
| { |
| return xopen3(pathname, flags, 0666); |
| } |
| |
| /* Die if we can't open an existing file readonly with O_NONBLOCK |
| * and return the fd. |
| * Note that for ioctl O_RDONLY is sufficient. |
| */ |
| int FAST_FUNC xopen_nonblocking(const char *pathname) |
| { |
| return xopen(pathname, O_RDONLY | O_NONBLOCK); |
| } |
| |
| // Warn if we can't open a file and return a fd. |
| int FAST_FUNC open3_or_warn(const char *pathname, int flags, int mode) |
| { |
| int ret; |
| |
| ret = open(pathname, flags, mode); |
| if (ret < 0) { |
| bb_perror_msg("can't open '%s'", pathname); |
| } |
| return ret; |
| } |
| |
| // Warn if we can't open a file and return a fd. |
| int FAST_FUNC open_or_warn(const char *pathname, int flags) |
| { |
| return open3_or_warn(pathname, flags, 0666); |
| } |
| |
| void FAST_FUNC xunlink(const char *pathname) |
| { |
| if (unlink(pathname)) |
| bb_perror_msg_and_die("can't remove file '%s'", pathname); |
| } |
| |
| void FAST_FUNC xrename(const char *oldpath, const char *newpath) |
| { |
| if (rename(oldpath, newpath)) |
| bb_perror_msg_and_die("can't move '%s' to '%s'", oldpath, newpath); |
| } |
| |
| int FAST_FUNC rename_or_warn(const char *oldpath, const char *newpath) |
| { |
| int n = rename(oldpath, newpath); |
| if (n) |
| bb_perror_msg("can't move '%s' to '%s'", oldpath, newpath); |
| return n; |
| } |
| |
| void FAST_FUNC xpipe(int filedes[2]) |
| { |
| if (pipe(filedes)) |
| bb_perror_msg_and_die("can't create pipe"); |
| } |
| |
| void FAST_FUNC xdup2(int from, int to) |
| { |
| if (dup2(from, to) != to) |
| bb_perror_msg_and_die("can't duplicate file descriptor"); |
| } |
| |
| // "Renumber" opened fd |
| void FAST_FUNC xmove_fd(int from, int to) |
| { |
| if (from == to) |
| return; |
| xdup2(from, to); |
| close(from); |
| } |
| |
| // Die with an error message if we can't write the entire buffer. |
| void FAST_FUNC xwrite(int fd, const void *buf, size_t count) |
| { |
| if (count) { |
| ssize_t size = full_write(fd, buf, count); |
| if ((size_t)size != count) |
| bb_error_msg_and_die("short write"); |
| } |
| } |
| void FAST_FUNC xwrite_str(int fd, const char *str) |
| { |
| xwrite(fd, str, strlen(str)); |
| } |
| |
| void FAST_FUNC xclose(int fd) |
| { |
| if (close(fd)) |
| bb_perror_msg_and_die("close failed"); |
| } |
| |
| // Die with an error message if we can't lseek to the right spot. |
| off_t FAST_FUNC xlseek(int fd, off_t offset, int whence) |
| { |
| off_t off = lseek(fd, offset, whence); |
| if (off == (off_t)-1) { |
| if (whence == SEEK_SET) |
| bb_perror_msg_and_die("lseek(%"OFF_FMT"u)", offset); |
| bb_perror_msg_and_die("lseek"); |
| } |
| return off; |
| } |
| |
| // Die with supplied filename if this FILE* has ferror set. |
| void FAST_FUNC die_if_ferror(FILE *fp, const char *fn) |
| { |
| if (ferror(fp)) { |
| /* ferror doesn't set useful errno */ |
| bb_error_msg_and_die("%s: I/O error", fn); |
| } |
| } |
| |
| // Die with an error message if stdout has ferror set. |
| void FAST_FUNC die_if_ferror_stdout(void) |
| { |
| die_if_ferror(stdout, bb_msg_standard_output); |
| } |
| |
| int FAST_FUNC fflush_all(void) |
| { |
| return fflush(NULL); |
| } |
| |
| |
| int FAST_FUNC bb_putchar(int ch) |
| { |
| return putchar(ch); |
| } |
| |
| /* Die with an error message if we can't copy an entire FILE* to stdout, |
| * then close that file. */ |
| void FAST_FUNC xprint_and_close_file(FILE *file) |
| { |
| fflush_all(); |
| // copyfd outputs error messages for us. |
| if (bb_copyfd_eof(fileno(file), STDOUT_FILENO) == -1) |
| xfunc_die(); |
| |
| fclose(file); |
| } |
| |
| // Die with an error message if we can't malloc() enough space and do an |
| // sprintf() into that space. |
| char* FAST_FUNC xasprintf(const char *format, ...) |
| { |
| va_list p; |
| int r; |
| char *string_ptr; |
| |
| va_start(p, format); |
| r = vasprintf(&string_ptr, format, p); |
| va_end(p); |
| |
| if (r < 0) |
| bb_error_msg_and_die(bb_msg_memory_exhausted); |
| return string_ptr; |
| } |
| |
| void FAST_FUNC xsetenv(const char *key, const char *value) |
| { |
| if (setenv(key, value, 1)) |
| bb_error_msg_and_die(bb_msg_memory_exhausted); |
| } |
| |
| /* Handles "VAR=VAL" strings, even those which are part of environ |
| * _right now_ |
| */ |
| void FAST_FUNC bb_unsetenv(const char *var) |
| { |
| char *tp = strchr(var, '='); |
| |
| if (!tp) { |
| unsetenv(var); |
| return; |
| } |
| |
| /* In case var was putenv'ed, we can't replace '=' |
| * with NUL and unsetenv(var) - it won't work, |
| * env is modified by the replacement, unsetenv |
| * sees "VAR" instead of "VAR=VAL" and does not remove it! |
| * horror :( */ |
| tp = xstrndup(var, tp - var); |
| unsetenv(tp); |
| free(tp); |
| } |
| |
| void FAST_FUNC bb_unsetenv_and_free(char *var) |
| { |
| bb_unsetenv(var); |
| free(var); |
| } |
| |
| // Die with an error message if we can't set gid. (Because resource limits may |
| // limit this user to a given number of processes, and if that fills up the |
| // setgid() will fail and we'll _still_be_root_, which is bad.) |
| void FAST_FUNC xsetgid(gid_t gid) |
| { |
| if (setgid(gid)) bb_perror_msg_and_die("setgid"); |
| } |
| |
| // Die with an error message if we can't set uid. (See xsetgid() for why.) |
| void FAST_FUNC xsetuid(uid_t uid) |
| { |
| if (setuid(uid)) bb_perror_msg_and_die("setuid"); |
| } |
| |
| // Die if we can't chdir to a new path. |
| void FAST_FUNC xchdir(const char *path) |
| { |
| if (chdir(path)) |
| bb_perror_msg_and_die("chdir(%s)", path); |
| } |
| |
| void FAST_FUNC xchroot(const char *path) |
| { |
| if (chroot(path)) |
| bb_perror_msg_and_die("can't change root directory to %s", path); |
| } |
| |
| // Print a warning message if opendir() fails, but don't die. |
| DIR* FAST_FUNC warn_opendir(const char *path) |
| { |
| DIR *dp; |
| |
| dp = opendir(path); |
| if (!dp) |
| bb_perror_msg("can't open '%s'", path); |
| return dp; |
| } |
| |
| // Die with an error message if opendir() fails. |
| DIR* FAST_FUNC xopendir(const char *path) |
| { |
| DIR *dp; |
| |
| dp = opendir(path); |
| if (!dp) |
| bb_perror_msg_and_die("can't open '%s'", path); |
| return dp; |
| } |
| |
| // Die with an error message if we can't open a new socket. |
| int FAST_FUNC xsocket(int domain, int type, int protocol) |
| { |
| int r = socket(domain, type, protocol); |
| |
| if (r < 0) { |
| /* Hijack vaguely related config option */ |
| #if ENABLE_VERBOSE_RESOLUTION_ERRORS |
| const char *s = "INET"; |
| # ifdef AF_PACKET |
| if (domain == AF_PACKET) s = "PACKET"; |
| # endif |
| # ifdef AF_NETLINK |
| if (domain == AF_NETLINK) s = "NETLINK"; |
| # endif |
| IF_FEATURE_IPV6(if (domain == AF_INET6) s = "INET6";) |
| bb_perror_msg_and_die("socket(AF_%s,%d,%d)", s, type, protocol); |
| #else |
| bb_perror_msg_and_die("socket"); |
| #endif |
| } |
| |
| return r; |
| } |
| |
| // Die with an error message if we can't bind a socket to an address. |
| void FAST_FUNC xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen) |
| { |
| if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind"); |
| } |
| |
| // Die with an error message if we can't listen for connections on a socket. |
| void FAST_FUNC xlisten(int s, int backlog) |
| { |
| if (listen(s, backlog)) bb_perror_msg_and_die("listen"); |
| } |
| |
| /* Die with an error message if sendto failed. |
| * Return bytes sent otherwise */ |
| ssize_t FAST_FUNC xsendto(int s, const void *buf, size_t len, const struct sockaddr *to, |
| socklen_t tolen) |
| { |
| ssize_t ret = sendto(s, buf, len, 0, to, tolen); |
| if (ret < 0) { |
| if (ENABLE_FEATURE_CLEAN_UP) |
| close(s); |
| bb_perror_msg_and_die("sendto"); |
| } |
| return ret; |
| } |
| |
| // xstat() - a stat() which dies on failure with meaningful error message |
| void FAST_FUNC xstat(const char *name, struct stat *stat_buf) |
| { |
| if (stat(name, stat_buf)) |
| bb_perror_msg_and_die("can't stat '%s'", name); |
| } |
| |
| // selinux_or_die() - die if SELinux is disabled. |
| void FAST_FUNC selinux_or_die(void) |
| { |
| #if ENABLE_SELINUX |
| int rc = is_selinux_enabled(); |
| if (rc == 0) { |
| bb_error_msg_and_die("SELinux is disabled"); |
| } else if (rc < 0) { |
| bb_error_msg_and_die("is_selinux_enabled() failed"); |
| } |
| #else |
| bb_error_msg_and_die("SELinux support is disabled"); |
| #endif |
| } |
| |
| int FAST_FUNC ioctl_or_perror_and_die(int fd, unsigned request, void *argp, const char *fmt,...) |
| { |
| int ret; |
| va_list p; |
| |
| ret = ioctl(fd, request, argp); |
| if (ret < 0) { |
| va_start(p, fmt); |
| bb_verror_msg(fmt, p, strerror(errno)); |
| /* xfunc_die can actually longjmp, so be nice */ |
| va_end(p); |
| xfunc_die(); |
| } |
| return ret; |
| } |
| |
| int FAST_FUNC ioctl_or_perror(int fd, unsigned request, void *argp, const char *fmt,...) |
| { |
| va_list p; |
| int ret = ioctl(fd, request, argp); |
| |
| if (ret < 0) { |
| va_start(p, fmt); |
| bb_verror_msg(fmt, p, strerror(errno)); |
| va_end(p); |
| } |
| return ret; |
| } |
| |
| #if ENABLE_IOCTL_HEX2STR_ERROR |
| int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp, const char *ioctl_name) |
| { |
| int ret; |
| |
| ret = ioctl(fd, request, argp); |
| if (ret < 0) |
| bb_simple_perror_msg(ioctl_name); |
| return ret; |
| } |
| int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp, const char *ioctl_name) |
| { |
| int ret; |
| |
| ret = ioctl(fd, request, argp); |
| if (ret < 0) |
| bb_simple_perror_msg_and_die(ioctl_name); |
| return ret; |
| } |
| #else |
| int FAST_FUNC bb_ioctl_or_warn(int fd, unsigned request, void *argp) |
| { |
| int ret; |
| |
| ret = ioctl(fd, request, argp); |
| if (ret < 0) |
| bb_perror_msg("ioctl %#x failed", request); |
| return ret; |
| } |
| int FAST_FUNC bb_xioctl(int fd, unsigned request, void *argp) |
| { |
| int ret; |
| |
| ret = ioctl(fd, request, argp); |
| if (ret < 0) |
| bb_perror_msg_and_die("ioctl %#x failed", request); |
| return ret; |
| } |
| #endif |
| |
| char* FAST_FUNC xmalloc_ttyname(int fd) |
| { |
| char *buf = xzalloc(128); |
| int r = ttyname_r(fd, buf, 127); |
| if (r) { |
| free(buf); |
| buf = NULL; |
| } |
| return buf; |
| } |
| |
| void FAST_FUNC generate_uuid(uint8_t *buf) |
| { |
| /* http://www.ietf.org/rfc/rfc4122.txt |
| * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | time_low | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | time_mid | time_hi_and_version | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * |clk_seq_and_variant | node (0-1) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * | node (2-5) | |
| * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| * IOW, uuid has this layout: |
| * uint32_t time_low (big endian) |
| * uint16_t time_mid (big endian) |
| * uint16_t time_hi_and_version (big endian) |
| * version is a 4-bit field: |
| * 1 Time-based |
| * 2 DCE Security, with embedded POSIX UIDs |
| * 3 Name-based (MD5) |
| * 4 Randomly generated |
| * 5 Name-based (SHA-1) |
| * uint16_t clk_seq_and_variant (big endian) |
| * variant is a 3-bit field: |
| * 0xx Reserved, NCS backward compatibility |
| * 10x The variant specified in rfc4122 |
| * 110 Reserved, Microsoft backward compatibility |
| * 111 Reserved for future definition |
| * uint8_t node[6] |
| * |
| * For version 4, these bits are set/cleared: |
| * time_hi_and_version & 0x0fff | 0x4000 |
| * clk_seq_and_variant & 0x3fff | 0x8000 |
| */ |
| pid_t pid; |
| int i; |
| |
| i = open("/dev/urandom", O_RDONLY); |
| if (i >= 0) { |
| read(i, buf, 16); |
| close(i); |
| } |
| /* Paranoia. /dev/urandom may be missing. |
| * rand() is guaranteed to generate at least [0, 2^15) range, |
| * but lowest bits in some libc are not so "random". */ |
| srand(monotonic_us()); /* pulls in printf */ |
| pid = getpid(); |
| while (1) { |
| for (i = 0; i < 16; i++) |
| buf[i] ^= rand() >> 5; |
| if (pid == 0) |
| break; |
| srand(pid); |
| pid = 0; |
| } |
| |
| /* version = 4 */ |
| buf[4 + 2 ] = (buf[4 + 2 ] & 0x0f) | 0x40; |
| /* variant = 10x */ |
| buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80; |
| } |
| |
| #if BB_MMU |
| pid_t FAST_FUNC xfork(void) |
| { |
| pid_t pid; |
| pid = fork(); |
| if (pid < 0) /* wtf? */ |
| bb_perror_msg_and_die("vfork"+1); |
| return pid; |
| } |
| #endif |