freebsd-src/usr.bin/cmp/link.c
Brian Somers e1bfde1b04 Add a -h option to tell cmp not to follow symbolic links.
MFC after:	3 weeks
Sponsored by:	Sophos/ActiveState
2005-08-23 13:13:13 +00:00

94 lines
2.6 KiB
C

/*-
* Copyright (c) 2005 Brian Somers <brian@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <err.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "extern.h"
void
c_link(const char *file1, off_t skip1, const char *file2, off_t skip2)
{
char buf1[PATH_MAX], *p1;
char buf2[PATH_MAX], *p2;
int dfound, len1, len2;
off_t byte;
u_char ch;
if ((len1 = readlink(file1, buf1, sizeof(buf1) - 1)) < 0) {
if (!sflag)
err(ERR_EXIT, "%s", file1);
else
exit(ERR_EXIT);
}
if ((len2 = readlink(file2, buf2, sizeof(buf2) - 1)) < 0) {
if (!sflag)
err(ERR_EXIT, "%s", file2);
else
exit(ERR_EXIT);
}
if (skip1 > len1)
skip1 = len1;
buf1[len1] = '\0';
if (skip2 > len2)
skip2 = len2;
buf2[len2] = '\0';
dfound = 0;
byte = 1;
for (p1 = buf1 + skip1, p2 = buf2 + skip2; *p1 && *p2; p1++, p2++) {
if ((ch = *p1) != *p2) {
if (xflag) {
dfound = 1;
(void)printf("%08llx %02x %02x\n",
(long long)byte - 1, ch, *p2);
} else if (lflag) {
dfound = 1;
(void)printf("%6lld %3o %3o\n",
(long long)byte, ch, *p2);
} else
diffmsg(file1, file2, byte, 1);
/* NOTREACHED */
}
byte++;
}
if (*p1 || *p2)
eofmsg (*p1 ? file2 : file1);
if (dfound)
exit(DIFF_EXIT);
}