busybox/coreutils/truncate.c

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/*
* Mini truncate implementation for busybox
*
* Copyright (C) 2015 by Ari Sundholm <ari@tuxera.com>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config TRUNCATE
//config: bool "truncate (4.7 kb)"
//config: default y
//config: help
//config: truncate truncates files to a given size. If a file does
//config: not exist, it is created unless told otherwise.
//applet:IF_TRUNCATE(APPLET_NOFORK(truncate, truncate, BB_DIR_USR_BIN, BB_SUID_DROP, truncate))
//kbuild:lib-$(CONFIG_TRUNCATE) += truncate.o
//usage:#define truncate_trivial_usage
//usage: "[-c] -s SIZE FILE..."
//usage:#define truncate_full_usage "\n\n"
//usage: "Truncate FILEs to the given size\n"
//usage: "\n -c Do not create files"
//usage: "\n -s SIZE Truncate to SIZE"
//usage:
//usage:#define truncate_example_usage
//usage: "$ truncate -s 1G foo"
#include "libbb.h"
#if ENABLE_LFS
# define XATOU_SFX xatoull_sfx
#else
# define XATOU_SFX xatoul_sfx
#endif
/* This is a NOFORK applet. Be very careful! */
int truncate_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int truncate_main(int argc UNUSED_PARAM, char **argv)
{
unsigned opts;
int flags = O_WRONLY | O_NONBLOCK;
int ret = EXIT_SUCCESS;
char *size_str;
off_t size;
enum {
OPT_NOCREATE = (1 << 0),
OPT_SIZE = (1 << 1),
};
getopt32: remove opt_complementary function old new delta vgetopt32 1318 1392 +74 runsvdir_main 703 713 +10 bb_make_directory 423 425 +2 collect_cpu 546 545 -1 opt_chars 3 - -3 opt_complementary 4 - -4 tftpd_main 567 562 -5 ntp_init 476 471 -5 zcip_main 1266 1256 -10 xxd_main 428 418 -10 whois_main 140 130 -10 who_main 463 453 -10 which_main 212 202 -10 wget_main 2535 2525 -10 watchdog_main 291 281 -10 watch_main 222 212 -10 vlock_main 399 389 -10 uuencode_main 332 322 -10 uudecode_main 316 306 -10 unlink_main 45 35 -10 udhcpd_main 1482 1472 -10 udhcpc_main 2762 2752 -10 tune2fs_main 290 280 -10 tunctl_main 366 356 -10 truncate_main 218 208 -10 tr_main 518 508 -10 time_main 1134 1124 -10 tftp_main 286 276 -10 telnetd_main 1873 1863 -10 tcpudpsvd_main 1785 1775 -10 taskset_main 521 511 -10 tar_main 1009 999 -10 tail_main 1644 1634 -10 syslogd_main 1967 1957 -10 switch_root_main 368 358 -10 svlogd_main 1454 1444 -10 sv 1296 1286 -10 stat_main 104 94 -10 start_stop_daemon_main 1028 1018 -10 split_main 542 532 -10 sort_main 796 786 -10 slattach_main 624 614 -10 shuf_main 504 494 -10 setsid_main 96 86 -10 setserial_main 1132 1122 -10 setfont_main 388 378 -10 setconsole_main 78 68 -10 sendmail_main 1209 1199 -10 sed_main 677 667 -10 script_main 1077 1067 -10 run_parts_main 325 315 -10 rtcwake_main 454 444 -10 rm_main 175 165 -10 reformime_main 119 109 -10 readlink_main 123 113 -10 rdate_main 246 236 -10 pwdx_main 189 179 -10 pstree_main 317 307 -10 pscan_main 663 653 -10 popmaildir_main 818 808 -10 pmap_main 80 70 -10 nc_main 1042 1032 -10 mv_main 558 548 -10 mountpoint_main 477 467 -10 mount_main 1264 1254 -10 modprobe_main 768 758 -10 modinfo_main 333 323 -10 mktemp_main 200 190 -10 mkswap_main 324 314 -10 mkfs_vfat_main 1489 1479 -10 microcom_main 715 705 -10 md5_sha1_sum_main 521 511 -10 man_main 867 857 -10 makedevs_main 1052 1042 -10 ls_main 563 553 -10 losetup_main 432 422 -10 loadfont_main 89 79 -10 ln_main 524 514 -10 link_main 75 65 -10 ipcalc_main 544 534 -10 iostat_main 2397 2387 -10 install_main 768 758 -10 id_main 480 470 -10 i2cset_main 1239 1229 -10 i2cget_main 380 370 -10 i2cdump_main 1482 1472 -10 i2cdetect_main 682 672 -10 hwclock_main 406 396 -10 httpd_main 741 731 -10 grep_main 837 827 -10 getty_main 1559 1549 -10 fuser_main 297 287 -10 ftpgetput_main 345 335 -10 ftpd_main 2232 2222 -10 fstrim_main 251 241 -10 fsfreeze_main 77 67 -10 fsck_minix_main 2921 2911 -10 flock_main 314 304 -10 flashcp_main 740 730 -10 flash_eraseall_main 833 823 -10 fdformat_main 532 522 -10 expand_main 680 670 -10 eject_main 335 325 -10 dumpleases_main 630 620 -10 du_main 314 304 -10 dos2unix_main 441 431 -10 diff_main 1350 1340 -10 df_main 1064 1054 -10 date_main 1095 1085 -10 cut_main 961 951 -10 cryptpw_main 228 218 -10 crontab_main 575 565 -10 crond_main 1149 1139 -10 cp_main 370 360 -10 common_traceroute_main 3834 3824 -10 common_ping_main 1767 1757 -10 comm_main 239 229 -10 cmp_main 655 645 -10 chrt_main 379 369 -10 chpst_main 704 694 -10 chpasswd_main 308 298 -10 chown_main 171 161 -10 chmod_main 158 148 -10 cat_main 428 418 -10 bzip2_main 120 110 -10 blkdiscard_main 264 254 -10 base64_main 221 211 -10 arping_main 1665 1655 -10 ar_main 556 546 -10 adjtimex_main 406 396 -10 adduser_main 882 872 -10 addgroup_main 411 401 -10 acpid_main 1198 1188 -10 optstring 11 - -11 opt_string 18 - -18 OPT_STR 25 - -25 ubi_tools_main 1288 1258 -30 ls_options 31 - -31 ------------------------------------------------------------------------------ (add/remove: 0/6 grow/shrink: 3/129 up/down: 86/-1383) Total: -1297 bytes text data bss dec hex filename 915428 485 6876 922789 e14a5 busybox_old 914629 485 6872 921986 e1182 busybox_unstripped Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-08-09 01:25:02 +05:30
opts = getopt32(argv, "^" "cs:" "\0" "s:-1", &size_str);
if (!(opts & OPT_NOCREATE))
flags |= O_CREAT;
// TODO: coreutils 8.17 also support "m" (lowercase) suffix
// with truncate, but not with dd!
// We share kMG_suffixes[], so we can't make both tools
// compatible at once...
size = XATOU_SFX(size_str, kMG_suffixes);
argv += optind;
while (*argv) {
truncate: always set mode when opening file to avoid fortify errors Busybox crashes due to no mode being given when opening: $ ./busybox truncate -s 1M foo *** invalid open64 call: O_CREAT without mode ***: ./busybox terminated ======= Backtrace: ========= /lib/x86_64-linux-gnu/libc.so.6(+0x7338f)[0x7f66d921338f] /lib/x86_64-linux-gnu/libc.so.6(__fortify_fail+0x5c)[0x7f66d92aac9c] /lib/x86_64-linux-gnu/libc.so.6(+0xeb6aa)[0x7f66d928b6aa] ./busybox[0x4899f9] ======= Memory map: ======== 00400000-004d0000 r-xp 00000000 00:1a 137559 /home/ari/busybox/busybox 006cf000-006d0000 r--p 000cf000 00:1a 137559 /home/ari/busybox/busybox 006d0000-006d1000 rw-p 000d0000 00:1a 137559 /home/ari/busybox/busybox 006d1000-006d4000 rw-p 00000000 00:00 0 014e7000-01508000 rw-p 00000000 00:00 0 [heap] 7f66d8f8a000-7f66d8fa0000 r-xp 00000000 08:07 1579008 /lib/x86_64-linux-gnu/libgcc_s.so.1 7f66d8fa0000-7f66d919f000 ---p 00016000 08:07 1579008 /lib/x86_64-linux-gnu/libgcc_s.so.1 7f66d919f000-7f66d91a0000 rw-p 00015000 08:07 1579008 /lib/x86_64-linux-gnu/libgcc_s.so.1 7f66d91a0000-7f66d935b000 r-xp 00000000 08:07 1578994 /lib/x86_64-linux-gnu/libc-2.19.so 7f66d935b000-7f66d955a000 ---p 001bb000 08:07 1578994 /lib/x86_64-linux-gnu/libc-2.19.so 7f66d955a000-7f66d955e000 r--p 001ba000 08:07 1578994 /lib/x86_64-linux-gnu/libc-2.19.so 7f66d955e000-7f66d9560000 rw-p 001be000 08:07 1578994 /lib/x86_64-linux-gnu/libc-2.19.so 7f66d9560000-7f66d9565000 rw-p 00000000 00:00 0 7f66d9565000-7f66d966a000 r-xp 00000000 08:07 1579020 /lib/x86_64-linux-gnu/libm-2.19.so 7f66d966a000-7f66d9869000 ---p 00105000 08:07 1579020 /lib/x86_64-linux-gnu/libm-2.19.so 7f66d9869000-7f66d986a000 r--p 00104000 08:07 1579020 /lib/x86_64-linux-gnu/libm-2.19.so 7f66d986a000-7f66d986b000 rw-p 00105000 08:07 1579020 /lib/x86_64-linux-gnu/libm-2.19.so 7f66d986b000-7f66d988e000 r-xp 00000000 08:07 1578981 /lib/x86_64-linux-gnu/ld-2.19.so 7f66d9a64000-7f66d9a67000 rw-p 00000000 00:00 0 7f66d9a8a000-7f66d9a8d000 rw-p 00000000 00:00 0 7f66d9a8d000-7f66d9a8e000 r--p 00022000 08:07 1578981 /lib/x86_64-linux-gnu/ld-2.19.so 7f66d9a8e000-7f66d9a8f000 rw-p 00023000 08:07 1578981 /lib/x86_64-linux-gnu/ld-2.19.so 7f66d9a8f000-7f66d9a90000 rw-p 00000000 00:00 0 7ffc47761000-7ffc47782000 rw-p 00000000 00:00 0 [stack] 7ffc477ab000-7ffc477ad000 r-xp 00000000 00:00 0 [vdso] ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall] Aborted (core dumped) $ Fix this by simply always setting the mode, as it doesn't hurt even when O_CREAT is not specified. This bug is a regression introduced in fc3e40e, as xopen(), which was originally used, would automatically set the mode. Signed-off-by: Ari Sundholm <ari@tuxera.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2016-01-04 19:10:37 +05:30
int fd = open(*argv, flags, 0666);
if (fd < 0) {
if (errno != ENOENT || !(opts & OPT_NOCREATE)) {
bb_perror_msg("%s: open", *argv);
ret = EXIT_FAILURE;
}
/* else: ENOENT && OPT_NOCREATE:
* do not report error, exitcode is also 0.
*/
} else {
if (ftruncate(fd, size) == -1) {
bb_perror_msg("%s: truncate", *argv);
ret = EXIT_FAILURE;
}
xclose(fd);
}
++argv;
}
return ret;
}