busybox/coreutils/uniq.c
Denis Vlasenko 6ca409e0e4 trylink: produce even more info about final link stage
trylink: explain how to modify link and drastically decrease amount
  of padding (unfortunately, needs hand editing ATM).
*: add ALIGN1 / ALIGN2 to global strings and arrays of bytes and shorts

size saving: 0.5k
2007-08-12 20:58:27 +00:00

104 lines
2.0 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 const char uniq_opts[] ALIGN1 = "cdu" "f:s:" "cdu\0\1\2\4";
static FILE *xgetoptfile_uniq_s(char **argv, int read0write2)
{
const char *n;
n = *argv;
if (n != NULL) {
if ((*n != '-') || n[1]) {
return xfopen(n, "r\0w" + read0write2);
}
}
return (read0write2) ? stdout : stdin;
}
int uniq_main(int argc, char **argv);
int uniq_main(int argc, char **argv)
{
FILE *in, *out;
unsigned long dups, skip_fields, skip_chars, i;
const char *s0, *e0, *s1, *e1, *input_filename;
unsigned opt;
enum {
OPT_c = 0x1,
OPT_d = 0x2,
OPT_u = 0x4,
OPT_f = 0x8,
OPT_s = 0x10,
};
skip_fields = skip_chars = 0;
opt = getopt32(argc, argv, "cduf:s:", &s0, &s1);
if (opt & OPT_f)
skip_fields = xatoul(s0);
if (opt & OPT_s)
skip_chars = xatoul(s1);
argv += optind;
input_filename = *argv;
in = xgetoptfile_uniq_s(argv, 0);
if (*argv) {
++argv;
}
out = xgetoptfile_uniq_s(argv, 2);
if (*argv && argv[1]) {
bb_show_usage();
}
s1 = e1 = NULL; /* prime the pump */
do {
s0 = s1;
e0 = e1;
dups = 0;
/* gnu uniq ignores newlines */
while ((s1 = xmalloc_getline(in)) != NULL) {
e1 = s1;
for (i = skip_fields; i; i--) {
e1 = skip_whitespace(e1);
e1 = skip_non_whitespace(e1);
}
for (i = skip_chars; *e1 && i; i--) {
++e1;
}
if (!s0 || strcmp(e0, e1)) {
break;
}
++dups; /* Note: Testing for overflow seems excessive. */
}
if (s0) {
if (!(opt & (OPT_d << !!dups))) { /* (if dups, opt & OPT_e) */
fprintf(out, "\0%d " + (opt & 1), dups + 1);
fprintf(out, "%s\n", s0);
}
free((void *)s0);
}
} while (s1);
die_if_ferror(in, input_filename);
fflush_stdout_and_exit(EXIT_SUCCESS);
}