busybox/coreutils/uniq.c

108 lines
2.5 KiB
C
Raw Normal View History

/* vi: set sw=4 ts=4: */
/*
2003-03-19 14:43:01 +05:30
* uniq implementation for busybox
*
* Copyright (C) 2005 Manuel Novoa III <mjn3@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
2003-03-19 14:43:01 +05:30
/* BB_AUDIT SUSv3 compliant */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/uniq.html */
#include "libbb.h"
int uniq_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2008-07-05 14:48:54 +05:30
int uniq_main(int argc UNUSED_PARAM, char **argv)
{
const char *input_filename;
unsigned skip_fields, skip_chars, max_chars;
2007-03-31 15:49:11 +05:30
unsigned opt;
char *cur_line;
const char *cur_compare;
2007-03-31 15:49:11 +05:30
enum {
OPT_c = 0x1,
OPT_d = 0x2, /* print only dups */
OPT_u = 0x4, /* print only uniq */
2007-03-31 15:49:11 +05:30
OPT_f = 0x8,
OPT_s = 0x10,
OPT_w = 0x20,
2007-03-31 15:49:11 +05:30
};
2003-03-19 14:43:01 +05:30
2007-03-31 15:49:11 +05:30
skip_fields = skip_chars = 0;
max_chars = INT_MAX;
2007-03-31 15:49:11 +05:30
opt_complementary = "f+:s+:w+";
opt = getopt32(argv, "cduf:s:w:", &skip_fields, &skip_chars, &max_chars);
2007-03-31 15:49:11 +05:30
argv += optind;
input_filename = argv[0];
if (input_filename) {
const char *output;
2003-03-19 14:43:01 +05:30
if (input_filename[0] != '-' || input_filename[1]) {
close(STDIN_FILENO); /* == 0 */
xopen(input_filename, O_RDONLY); /* fd will be 0 */
}
output = argv[1];
if (output) {
if (argv[2])
bb_show_usage();
if (output[0] != '-' || output[1]) {
// Won't work with "uniq - FILE" and closed stdin:
//close(STDOUT_FILENO);
//xopen(output, O_WRONLY | O_CREAT | O_TRUNC);
xmove_fd(xopen(output, O_WRONLY | O_CREAT | O_TRUNC), STDOUT_FILENO);
}
}
}
2003-03-19 14:43:01 +05:30
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;
2000-01-07 05:19:21 +05:30
/* gnu uniq ignores newlines */
while ((cur_line = xmalloc_fgetline(stdin)) != NULL) {
cur_compare = cur_line;
2006-10-27 04:51:47 +05:30
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 */
2003-03-19 14:43:01 +05:30
}
if (old_line) {
if (!(opt & (OPT_d << !!dups))) { /* (if dups, opt & OPT_u) */
if (opt & OPT_c) {
/* %7lu matches GNU coreutils 6.9 */
printf("%7lu ", dups + 1);
}
printf("%s\n", old_line);
2003-03-19 14:43:01 +05:30
}
free(old_line);
}
} while (cur_line);
2000-01-07 05:19:21 +05:30
die_if_ferror(stdin, input_filename);
2003-03-19 14:43:01 +05:30
2006-10-27 04:51:47 +05:30
fflush_stdout_and_exit(EXIT_SUCCESS);
}