sbase/cmp.c

87 lines
1.5 KiB
C

/* See LICENSE file for copyright and license details. */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "util.h"
enum { Same = 0, Diff = 1, Error = 2 };
static void
usage(void)
{
enprintf(Error, "usage: %s [-l | -s] file1 file2\n", argv0);
}
int
main(int argc, char *argv[])
{
int lflag = 0;
int sflag = 0;
int same = 1;
int b[2], i;
long line = 1, n = 1;
FILE *fp[2];
ARGBEGIN {
case 'l':
lflag = 1;
break;
case 's':
sflag = 1;
break;
default:
usage();
} ARGEND;
if (argc != 2 || (lflag && sflag))
usage();
if (argv[0][0] == '-' && !argv[0][1])
argv[0] = "/dev/fd/0";
fp[0] = fopen(argv[0], "r");
if (!fp[0]) {
if (!sflag)
weprintf("fopen %s:", argv[0]);
exit(Error);
}
if (argv[1][0] == '-' && !argv[1][1])
argv[1] = "/dev/fd/0";
fp[1] = fopen(argv[1], "r");
if (!fp[1]) {
if (!sflag)
weprintf("fopen %s:", argv[1]);
exit(Error);
}
for (n = 1; ; n++) {
b[0] = getc(fp[0]);
b[1] = getc(fp[1]);
if (b[0] == EOF && b[1] == EOF)
break;
if (b[0] == '\n' && b[1] == '\n')
line++;
if (b[0] == b[1])
continue;
for (i = 0; i < 2; i++) {
if (b[i] == EOF) {
if (!sflag)
fprintf(stderr, "cmp: EOF on %s\n",
!argv[i] ? "<stdin>" : argv[i]);
exit(Diff);
}
}
if (!lflag) {
if (!sflag)
printf("%s %s differ: char %ld, line %ld\n",
argv[0], !argv[1] ? "<stdin>" : argv[1], n, line);
exit(Diff);
} else {
printf("%ld %o %o\n", n, b[0], b[1]);
same = 0;
}
}
return same ? Same : Diff;
}