sbase/cmp.c

82 lines
1.3 KiB
C

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