hush/coreutils/uniq.c
Denys Vlasenko 1249dbb2c7 uniq: code shrink
function                                             old     new   delta
xgetoptfile_uniq_s                                    44      51      +7
uniq_main                                            389     368     -21
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 7/-21)             Total: -14 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-08-30 19:35:06 +02:00

109 lines
2.3 KiB
C

/* vi: set sw=4 ts=4: */
/*
* uniq implementation for busybox
*
* Copyright (C) 2005 Manuel Novoa III <mjn3@codepoet.org>
*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
/* BB_AUDIT SUSv3 compliant */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/uniq.html */
#include "libbb.h"
static void xgetoptfile_uniq_s(const char *n, int fd)
{
if (n == NULL)
return;
if ((n[0] == '-') && !n[1])
return;
/* close(fd); - optimization */
xmove_fd(
xopen3(n,
(fd == STDIN_FILENO) ? O_RDONLY : (O_WRONLY | O_CREAT | O_TRUNC),
0666),
fd);
}
int uniq_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int uniq_main(int argc UNUSED_PARAM, char **argv)
{
const char *input_filename;
unsigned skip_fields, skip_chars, max_chars;
unsigned opt;
char *cur_line;
const char *cur_compare;
enum {
OPT_c = 0x1,
OPT_d = 0x2, /* print only dups */
OPT_u = 0x4, /* print only uniq */
OPT_f = 0x8,
OPT_s = 0x10,
OPT_w = 0x20,
};
skip_fields = skip_chars = 0;
max_chars = INT_MAX;
opt_complementary = "f+:s+:w+";
opt = getopt32(argv, "cduf:s:w:", &skip_fields, &skip_chars, &max_chars);
argv += optind;
input_filename = *argv;
xgetoptfile_uniq_s(*argv, STDIN_FILENO);
if (*argv) {
++argv;
}
xgetoptfile_uniq_s(*argv, STDOUT_FILENO);
if (*argv && argv[1]) {
bb_show_usage();
}
cur_compare = cur_line = NULL; /* prime the pump */
do {
unsigned i;
unsigned long dups;
char *old_line;
const char *old_compare;
old_line = cur_line;
old_compare = cur_compare;
dups = 0;
/* gnu uniq ignores newlines */
while ((cur_line = xmalloc_fgetline(stdin)) != NULL) {
cur_compare = cur_line;
for (i = skip_fields; i; i--) {
cur_compare = skip_whitespace(cur_compare);
cur_compare = skip_non_whitespace(cur_compare);
}
for (i = skip_chars; *cur_compare && i; i--) {
++cur_compare;
}
if (!old_line || strncmp(old_compare, cur_compare, max_chars)) {
break;
}
free(cur_line);
++dups; /* testing for overflow seems excessive */
}
if (old_line) {
if (!(opt & (OPT_d << !!dups))) { /* (if dups, opt & OPT_u) */
printf("\0%lu " + (opt & 1), dups + 1); /* 1 == OPT_c */
printf("%s\n", old_line);
}
free(old_line);
}
} while (cur_line);
die_if_ferror(stdin, input_filename);
fflush_stdout_and_exit(EXIT_SUCCESS);
}