busybox/coreutils/cksum.c
Denis Vlasenko 62a90cdd74 *: shrink by using [f]open_or_warn_stdin where appropriate
function                                             old     new   delta
lsattr_main                                           62     143     +81
open_or_warn_stdin                                     -      36     +36
fclose_if_not_stdin                                   20      47     +27
xfopen_stdin                                           -      20     +20
tac_main                                             336     356     +20
cksum_main                                           249     259     +10
bb_argv_dash                                           -       8      +8
su_main                                              448     455      +7
cmp_main                                             630     633      +3
passwd_main                                         1072    1074      +2
uudecode_main                                        317     315      -2
text_yank                                            110     108      -2
handle_incoming_and_exit                            2653    2651      -2
flags                                                  5       1      -4
write_leases                                         235     230      -5
fopen_or_warn_stdin                                   48      42      -6
fold_main                                            648     642      -6
static.argv_dash                                       8       -      -8
sum_main                                             142     128     -14
tail_main                                           1237    1221     -16
sed_main                                             711     695     -16
cmp_xfopen_input                                      17       -     -17
bb_cat                                               113      96     -17
catv_main                                            328     306     -22
strings_main                                         457     434     -23
hash_file                                            298     274     -24
sum_file                                             353     325     -28
sort_main                                            904     859     -45
expand_main                                          736     686     -50
cut_main                                            1116    1065     -51
md5_sha1_sum_main                                    549     493     -56
lsattr_args                                           90       -     -90
read_stduu                                           408     255    -153
------------------------------------------------------------------------------
(add/remove: 3/3 grow/shrink: 7/20 up/down: 214/-657)        Total: -443 bytes
   text    data     bss     dec     hex filename
 797417     658    7428  805503   c4a7f busybox_old
 796973     658    7428  805059   c48c3 busybox_unstripped
2008-03-17 09:07:36 +00:00

57 lines
1.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* cksum - calculate the CRC32 checksum of a file
*
* Copyright (C) 2006 by Rob Sullivan, with ideas from code by Walter Harms
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */
#include "libbb.h"
int cksum_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int cksum_main(int argc ATTRIBUTE_UNUSED, char **argv)
{
uint32_t *crc32_table = crc32_filltable(NULL, 1);
uint32_t crc;
long length, filesize;
int bytes_read;
uint8_t *cp;
#if ENABLE_DESKTOP
getopt32(argv, ""); /* coreutils 6.9 compat */
argv += optind;
#else
argv++;
#endif
do {
int fd = open_or_warn_stdin(*argv ? *argv : bb_msg_standard_input);
if (fd < 0)
continue;
crc = 0;
length = 0;
#define read_buf bb_common_bufsiz1
while ((bytes_read = safe_read(fd, read_buf, sizeof(read_buf))) > 0) {
cp = read_buf;
length += bytes_read;
do {
crc = (crc << 8) ^ crc32_table[(crc >> 24) ^ *cp++];
} while (--bytes_read);
}
close(fd);
filesize = length;
for (; length; length >>= 8)
crc = (crc << 8) ^ crc32_table[((crc >> 24) ^ length) & 0xff];
crc ^= 0xffffffffL;
printf((*argv ? "%" PRIu32 " %li %s\n" : "%" PRIu32 " %li\n"),
crc, filesize, *argv);
} while (*argv && *++argv);
fflush_stdout_and_exit(EXIT_SUCCESS);
}