fdisk: code shrink without logic changes
function old new delta
create_doslabel 113 110 -3
set_start_sect 8 4 -4
set_nr_sects 8 4 -4
get_start_sect 8 4 -4
get_nr_sects 8 4 -4
store4_little_endian 21 - -21
read4_little_endian 33 - -33
is_cleared_partition 84 21 -63
------------------------------------------------------------------------------
(add/remove: 0/2 grow/shrink: 0/6 up/down: 0/-136) Total: -136 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/util-linux/fdisk.c b/util-linux/fdisk.c
index 980568b..cb15bd2 100644
--- a/util-linux/fdisk.c
+++ b/util-linux/fdisk.c
@@ -21,6 +21,13 @@
#endif
#include "libbb.h"
+#if BB_LITTLE_ENDIAN
+# define inline_if_little_endian ALWAYS_INLINE
+#else
+# define inline_if_little_endian /* nothing */
+#endif
+
+
/* Looks like someone forgot to add this to config system */
#ifndef ENABLE_FEATURE_FDISK_BLKSIZE
# define ENABLE_FEATURE_FDISK_BLKSIZE 0
@@ -181,7 +188,7 @@
sector_t offset; /* disk sector number */
char *sectorbuffer; /* disk sector contents */
#if ENABLE_FEATURE_FDISK_WRITABLE
- char changed; /* boolean */
+ char changed; /* boolean */
#endif
};
@@ -445,27 +452,6 @@
xmove_fd(xopen(bb_dev_null, O_RDONLY), dev_fd);
}
-#if ENABLE_FEATURE_FDISK_WRITABLE
-/* Read line; return 0 or first printable char */
-static int
-read_line(const char *prompt)
-{
- int sz;
-
- sz = read_line_input(prompt, line_buffer, sizeof(line_buffer), NULL);
- if (sz <= 0)
- exit(EXIT_SUCCESS); /* Ctrl-D or Ctrl-C */
-
- if (line_buffer[sz-1] == '\n')
- line_buffer[--sz] = '\0';
-
- line_ptr = line_buffer;
- while (*line_ptr != '\0' && (unsigned char)*line_ptr <= ' ')
- line_ptr++;
- return *line_ptr;
-}
-#endif
-
/*
* Return partition name - uses static storage
*/
@@ -497,30 +483,13 @@
if (lth) {
snprintf(bufp, bufsiz, "%*.*s%s%-2u",
- lth-wp-2, w, dev, p, pno);
+ lth-wp-2, w, dev, p, pno);
} else {
snprintf(bufp, bufsiz, "%.*s%s%-2u", w, dev, p, pno);
}
return bufp;
}
-#if ENABLE_FEATURE_FDISK_WRITABLE
-static void
-set_all_unchanged(void)
-{
- int i;
-
- for (i = 0; i < MAXIMUM_PARTS; i++)
- ptes[i].changed = 0;
-}
-
-static ALWAYS_INLINE void
-set_changed(int i)
-{
- ptes[i].changed = 1;
-}
-#endif /* FEATURE_FDISK_WRITABLE */
-
static ALWAYS_INLINE struct partition *
get_part_table(int i)
{
@@ -541,7 +510,67 @@
return (mbuffer[510] == 0x55 && (uint8_t)mbuffer[511] == 0xaa);
}
+static void fdisk_fatal(const char *why)
+{
+ if (listing) {
+ close_dev_fd();
+ longjmp(listingbuf, 1);
+ }
+ bb_error_msg_and_die(why, disk_device);
+}
+
+static void
+seek_sector(sector_t secno)
+{
+#if ENABLE_FDISK_SUPPORT_LARGE_DISKS
+ off64_t off = (off64_t)secno * sector_size;
+ if (lseek64(dev_fd, off, SEEK_SET) == (off64_t) -1)
+ fdisk_fatal(unable_to_seek);
+#else
+ uint64_t off = (uint64_t)secno * sector_size;
+ if (off > MAXINT(off_t)
+ || lseek(dev_fd, (off_t)off, SEEK_SET) == (off_t) -1
+ ) {
+ fdisk_fatal(unable_to_seek);
+ }
+#endif
+}
+
#if ENABLE_FEATURE_FDISK_WRITABLE
+/* Read line; return 0 or first printable char */
+static int
+read_line(const char *prompt)
+{
+ int sz;
+
+ sz = read_line_input(prompt, line_buffer, sizeof(line_buffer), NULL);
+ if (sz <= 0)
+ exit(EXIT_SUCCESS); /* Ctrl-D or Ctrl-C */
+
+ if (line_buffer[sz-1] == '\n')
+ line_buffer[--sz] = '\0';
+
+ line_ptr = line_buffer;
+ while (*line_ptr != '\0' && (unsigned char)*line_ptr <= ' ')
+ line_ptr++;
+ return *line_ptr;
+}
+
+static void
+set_all_unchanged(void)
+{
+ int i;
+
+ for (i = 0; i < MAXIMUM_PARTS; i++)
+ ptes[i].changed = 0;
+}
+
+static ALWAYS_INLINE void
+set_changed(int i)
+{
+ ptes[i].changed = 1;
+}
+
static ALWAYS_INLINE void
write_part_table_flag(char *b)
{
@@ -579,48 +608,18 @@
continue;
}
v = bb_strtoul(line_ptr, NULL, 16);
- if (v > 0xff)
- /* Bad input also triggers this */
- continue;
- return v;
+ if (v <= 0xff)
+ return v;
}
}
-#endif /* FEATURE_FDISK_WRITABLE */
-static void fdisk_fatal(const char *why)
-{
- if (listing) {
- close_dev_fd();
- longjmp(listingbuf, 1);
- }
- bb_error_msg_and_die(why, disk_device);
-}
-
-static void
-seek_sector(sector_t secno)
-{
-#if ENABLE_FDISK_SUPPORT_LARGE_DISKS
- off64_t off = (off64_t)secno * sector_size;
- if (lseek64(dev_fd, off, SEEK_SET) == (off64_t) -1)
- fdisk_fatal(unable_to_seek);
-#else
- uint64_t off = (uint64_t)secno * sector_size;
- if (off > MAXINT(off_t)
- || lseek(dev_fd, (off_t)off, SEEK_SET) == (off_t) -1
- ) {
- fdisk_fatal(unable_to_seek);
- }
-#endif
-}
-
-#if ENABLE_FEATURE_FDISK_WRITABLE
static void
write_sector(sector_t secno, const void *buf)
{
seek_sector(secno);
xwrite(dev_fd, buf, sector_size);
}
-#endif
+#endif /* FEATURE_FDISK_WRITABLE */
#include "fdisk_aix.c"
@@ -713,40 +712,42 @@
#include "fdisk_sun.c"
-#if ENABLE_FEATURE_FDISK_WRITABLE
-/* start_sect and nr_sects are stored little endian on all machines */
-/* moreover, they are not aligned correctly */
-static void
-store4_little_endian(unsigned char *cp, unsigned val)
-{
- cp[0] = val;
- cp[1] = val >> 8;
- cp[2] = val >> 16;
- cp[3] = val >> 24;
-}
-#endif /* FEATURE_FDISK_WRITABLE */
-
-static unsigned
+static inline_if_little_endian unsigned
read4_little_endian(const unsigned char *cp)
{
- return cp[0] + (cp[1] << 8) + (cp[2] << 16) + (cp[3] << 24);
+ uint32_t v;
+ move_from_unaligned32(v, cp);
+ return SWAP_LE32(v);
}
-#if ENABLE_FEATURE_FDISK_WRITABLE
-static void
-set_start_sect(struct partition *p, unsigned start_sect)
-{
- store4_little_endian(p->start4, start_sect);
-}
-#endif
-
static sector_t
get_start_sect(const struct partition *p)
{
return read4_little_endian(p->start4);
}
+static sector_t
+get_nr_sects(const struct partition *p)
+{
+ return read4_little_endian(p->size4);
+}
+
#if ENABLE_FEATURE_FDISK_WRITABLE
+/* start_sect and nr_sects are stored little endian on all machines */
+/* moreover, they are not aligned correctly */
+static inline_if_little_endian void
+store4_little_endian(unsigned char *cp, unsigned val)
+{
+ uint32_t v = SWAP_LE32(val);
+ move_to_unaligned32(cp, v);
+}
+
+static void
+set_start_sect(struct partition *p, unsigned start_sect)
+{
+ store4_little_endian(p->start4, start_sect);
+}
+
static void
set_nr_sects(struct partition *p, unsigned nr_sects)
{
@@ -754,12 +755,6 @@
}
#endif
-static sector_t
-get_nr_sects(const struct partition *p)
-{
- return read4_little_endian(p->size4);
-}
-
/* Allocate a buffer and read a partition table sector */
static void
read_pte(struct pte *pe, sector_t offset)
@@ -942,7 +937,7 @@
}
#else
#define get_sys_types() i386_sys_types
-#endif /* FEATURE_FDISK_WRITABLE */
+#endif
static const char *
partition_type(unsigned char type)
@@ -957,6 +952,24 @@
return "Unknown";
}
+static int
+is_cleared_partition(const struct partition *p)
+{
+ /* We consider partition "cleared" only if it has only zeros */
+ const char *cp = (const char *)p;
+ int cnt = sizeof(*p);
+ char bits = 0;
+ while (--cnt >= 0)
+ bits |= *cp++;
+ return (bits == 0);
+}
+
+static void
+clear_partition(struct partition *p)
+{
+ if (p)
+ memset(p, 0, sizeof(*p));
+}
#if ENABLE_FEATURE_FDISK_WRITABLE
static int
@@ -998,25 +1011,7 @@
} while (done < last[0]);
bb_putchar('\n');
}
-#endif /* FEATURE_FDISK_WRITABLE */
-static int
-is_cleared_partition(const struct partition *p)
-{
- return !(!p || p->boot_ind || p->head || p->sector || p->cyl ||
- p->sys_ind || p->end_head || p->end_sector || p->end_cyl ||
- get_start_sect(p) || get_nr_sects(p));
-}
-
-static void
-clear_partition(struct partition *p)
-{
- if (!p)
- return;
- memset(p, 0, sizeof(struct partition));
-}
-
-#if ENABLE_FEATURE_FDISK_WRITABLE
static void
set_partition(int i, int doext, sector_t start, sector_t stop, int sysid)
{
@@ -1189,26 +1184,22 @@
static void
create_doslabel(void)
{
- int i;
-
printf(msg_building_new_label, "DOS disklabel");
current_label_type = LABEL_DOS;
-
#if ENABLE_FEATURE_OSF_LABEL
possibly_osf_label = 0;
#endif
g_partitions = 4;
- for (i = 510-64; i < 510; i++)
- MBRbuffer[i] = 0;
+ memset(&MBRbuffer[510 - 4*16], 0, 4*16);
write_part_table_flag(MBRbuffer);
extended_offset = 0;
set_all_unchanged();
set_changed(0);
get_boot(CREATE_EMPTY_DOS);
}
-#endif /* FEATURE_FDISK_WRITABLE */
+#endif
static void
get_sectorsize(void)
@@ -1721,9 +1712,10 @@
ptes[i] = ptes[i+1];
i++;
}
- } else
+ } else {
/* the only logical: clear only */
clear_partition(ptes[i].part_table);
+ }
}
}