freebsd-skq/usr.bin/perl/perl.c
thomas cf69565b5f Prevent the wrapper from looping on itself forever, when there
is a symbolic link in the PATH pointing back to /usr/bin/perl.

Change WARNS from 6 to 5 to account for the fact that sys/time.h,
included from sys/stat.h, produces a warning when compiled with
-pedantic.

PR:		bin/42418
Reviewed by:	roberto
2002-09-10 13:56:30 +00:00

98 lines
3.3 KiB
C

/*-
* Copyright (c) 2002 Dag-Erling Coïdan Smørgrav
* 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
* in this position and unchanged.
* 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.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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/param.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "pathnames.h"
extern char **environ;
int
main(int argc __unused, char *argv[])
{
char path[PATH_MAX], *cp;
const char *cmd, *p, *q, *self;
size_t len;
struct stat self_stat, perl_stat;
self = argv[0];
if (stat (self, &self_stat) != 0) {
self_stat.st_dev = makedev (0, 0);
self_stat.st_ino = 0;
}
if ((cmd = strrchr(self, '/')) == NULL)
cmd = self;
else
cmd++;
/* If null path (e. g. in mailfilter scripts), use default path. */
if ((p = getenv("PATH")) == NULL) {
if (sysctlbyname("user.cs_path", (void *)NULL, &len,
(void *)NULL, 0) == -1)
err(1, "sysctlbyname(\"user.cs_path\")");
if ((cp = malloc(len + 1)) == NULL)
err(1, "malloc() failed");
if (sysctlbyname("user.cs_path", cp, &len, (void *)NULL, 0) == -1)
err(1, "sysctlbyname(\"user.cs_path\")");
setenv("PATH", cp, 1);
}
/* If default package bindir not there, append it. */
p = getenv("PATH");
if (strstr(p, PATH_PKG_BINDIR) == NULL) {
snprintf(path, sizeof path, "%s:%s", p, PATH_PKG_BINDIR);
setenv("PATH", path, 1);
}
argv[0] = path;
for (p = q = getenv("PATH"); p && *p && *q; p = q + 1) {
for (q = p; *q && *q != ':'; ++q)
/* nothing */ ;
len = snprintf(path, sizeof path, "%.*s/%s", (int)(q - p), p, cmd);
if (len >= PATH_MAX || strcmp(path, self) == 0)
continue;
if (stat (path, &perl_stat) == 0
&& self_stat.st_dev == perl_stat.st_dev
&& self_stat.st_ino == perl_stat.st_ino)
continue;
execve(path, argv, environ);
if (errno != ENOENT)
err(1, "%s", path);
}
errx(1, "Perl is not installed, try 'pkg_add -r perl'");
}