blockdev: code shrink

function                                             old     new   delta
blockdev_main                                        292     255     -37

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
This commit is contained in:
Denys Vlasenko 2010-09-06 17:37:52 +02:00
parent a35dfe6200
commit 571c5ab768

View File

@ -3,7 +3,7 @@
*
* Copyright (C) 2010 Sergey Naumov <sknaumov@gmail.com>
*
* Licensed under GPLv2, see file LICENSE in this source tree.
* Licensed under GPLv2, see file License in this tarball for details.
*/
//applet:IF_BLOCKDEV(APPLET(blockdev, _BB_DIR_SBIN, _BB_SUID_DROP))
@ -39,7 +39,8 @@ enum {
ARG_NONE = 0,
ARG_INT = 1,
ARG_ULONG = 2,
ARG_ULLONG = 3,
/* Yes, BLKGETSIZE64 takes pointer to uint64_t, not ullong! */
ARG_U64 = 3,
ARG_MASK = 3,
FL_USRARG = 4, /* argument is provided by user */
@ -92,7 +93,7 @@ static const struct bdc bdcommands[] = {
},{
.ioc = BLKGETSIZE64,
.name = "getsize64",
.flags = ARG_ULLONG,
.flags = ARG_U64,
.argval = -1,
},{
.ioc = BLKFLSBUF,
@ -125,55 +126,66 @@ int blockdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int blockdev_main(int argc, char **argv)
{
const struct bdc *bdcmd;
void *ioctl_ptr;
int fd;
int iarg;
unsigned long lu;
unsigned long long llu;
uint64_t u64;
union {
int i;
unsigned long lu;
uint64_t u64;
} ioctl_val_on_stack;
if ((unsigned)(argc - 3) > 1) /* must have 2 or 3 args */
bb_show_usage();
bdcmd = find_cmd(*++argv);
llu = (int)bdcmd->argval;
u64 = (int)bdcmd->argval;
if (bdcmd->flags & FL_USRARG)
llu = xatoi_positive(*++argv);
lu = llu;
iarg = llu;
u64 = xatoi_positive(*++argv);
if (!*++argv || argv[1])
bb_show_usage();
fd = xopen(*argv, O_RDONLY);
ioctl_ptr = NULL;
ioctl_val_on_stack.u64 = u64;
#if BB_BIG_ENDIAN
/* Store data properly wrt data size.
* (1) It's no-op for little-endian.
* (2) it's no-op for 0 and -1. Only --setro uses arg != 0 and != -1,
* and it is ARG_INT. --setbsz USER_VAL is also ARG_INT.
* Thus, we don't need to handle ARG_ULONG.
*/
switch (bdcmd->flags & ARG_MASK) {
case ARG_INT:
ioctl_ptr = &iarg;
ioctl_val_on_stack.i = (int)u64;
break;
# if 0 /* unused */
case ARG_ULONG:
ioctl_ptr = &lu;
break;
case ARG_ULLONG:
ioctl_ptr = &llu;
ioctl_val_on_stack.lu = (unsigned long)u64;
break;
# endif
}
#endif
if (ioctl(fd, bdcmd->ioc, ioctl_ptr) == -1)
if (ioctl(fd, bdcmd->ioc, &ioctl_val_on_stack.u64) == -1)
bb_simple_perror_msg_and_die(*argv);
/* Fetch it into register(s) */
u64 = ioctl_val_on_stack.u64;
/* Zero- or one-extend the value if needed, then print */
switch (bdcmd->flags & (ARG_MASK+FL_NORESULT)) {
case ARG_INT:
/* Smaller code when we use long long
* (gcc tail-merges printf call)
*/
printf("%lld\n", (long long)iarg);
printf("%lld\n", (long long)(int)u64);
break;
case ARG_ULONG:
llu = lu;
u64 = (unsigned long)u64;
/* FALLTHROUGH */
case ARG_ULLONG:
printf("%llu\n", llu);
case ARG_U64:
printf("%llu\n", (unsigned long long)u64);
break;
}