busybox/coreutils/sort.c

93 lines
2.2 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini sort implementation for busybox
*
*
* Copyright (C) 2000 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <getopt.h>
#include <string.h>
#include <stdlib.h>
#include "busybox.h"
static int compare_ascii(const void *x, const void *y)
{
return strcmp(*(char **)x, *(char **)y);
}
static int compare_numeric(const void *x, const void *y)
{
int z = atoi(*(char **)x) - atoi(*(char **)y);
return z ? z : strcmp(*(char **)x, *(char **)y);
}
int sort_main(int argc, char **argv)
{
FILE *fp;
char *line, **lines = NULL;
int i, opt, nlines = 0;
int (*compare)(const void *, const void *) = compare_ascii;
#ifdef BB_FEATURE_SORT_REVERSE
int reverse = FALSE;
#endif
while ((opt = getopt(argc, argv, "nr")) != -1) {
switch (opt) {
case 'n':
compare = compare_numeric;
break;
#ifdef BB_FEATURE_SORT_REVERSE
case 'r':
reverse = TRUE;
break;
#endif
default:
show_usage();
}
}
/* read the input */
for (i = optind; i == optind || i < argc; i++) {
if (argv[i] == NULL)
fp = stdin;
else
fp = xfopen(argv[i], "r");
while ((line = get_line_from_file(fp)) != NULL) {
lines = xrealloc(lines, sizeof(char *) * (nlines + 1));
line[strlen(line) - 1] = '\0';
lines[nlines++] = line;
}
}
/* sort it */
qsort(lines, nlines, sizeof(char *), compare);
/* print it */
#ifdef BB_FEATURE_SORT_REVERSE
if (reverse)
for (i = nlines - 1; 0 <= i; i--)
puts(lines[i]);
else
#endif
for (i = 0; i < nlines; i++)
puts(lines[i]);
return EXIT_SUCCESS;
}