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/* $OpenBSD: which.c,v 1.13 2004/09/24 19:45:27 fgsch Exp $ */
/*
* Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef lint
static const char rcsid[] = "$OpenBSD: which.c,v 1.13 2004/09/24 19:45:27 fgsch Exp $";
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <err.h>
#include <errno.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define PROG_WHICH 1
#define PROG_WHEREIS 2
extern char *__progname;
int findprog(char *, char *, int, int);
__dead void usage(void);
/*
* which(1) -- find an executable(s) in the user's path
* whereis(1) -- find an executable(s) in the default user path
*
* Return values:
* 0 - all executables found
* 1 - some found, some not
* 2 - none found
*/
int
main(int argc, char *argv[])
{
char *path;
size_t n;
int ch, allmatches = 0, notfound = 0, progmode = PROG_WHICH;
(void)setlocale(LC_ALL, "");
if (argc == 1)
usage();
/* Don't accept command args but check since old whereis(1) used to */
while ((ch = getopt(argc, argv, "a")) != -1) {
switch (ch) {
case 'a':
allmatches = 1;
break;
default:
usage();
}
}
/*
* which(1) uses user's $PATH.
* whereis(1) uses user.cs_path from sysctl(3).
*/
if (strcmp(__progname, "whereis") == 0) {
int mib[2];
progmode = PROG_WHEREIS;
mib[0] = CTL_USER;
mib[1] = USER_CS_PATH;
if (sysctl(mib, 2, NULL, &n, NULL, 0) == -1)
err(1, "unable to get length of user.cs_path");
if (n == 0)
errx(1, "user.cs_path was zero length!");
if ((path = (char *)malloc(n)) == NULL)
errx(1, "can't allocate memory.");
if (sysctl(mib, 2, path, &n, NULL, 0) == -1)
err(1, "unable to get user.cs_path");
} else {
if ((path = getenv("PATH")) == NULL)
err(1, "can't get $PATH from environment");
}
/* To make access(2) do what we want */
if (setgid(getegid()))
err(1, "Can't set gid to %u", getegid());
if (setuid(geteuid()))
err(1, "Can't set uid to %u", geteuid());
for (n = optind; n < argc; n++)
if (findprog(argv[n], path, progmode, allmatches) == 0)
notfound++;
exit((notfound == 0) ? 0 : ((notfound == argc - 1) ? 2 : 1));
}
int
findprog(char *prog, char *path, int progmode, int allmatches)
{
char *p, filename[MAXPATHLEN];
int proglen, plen, rval = 0;
struct stat sbuf;
char *pathcpy;
/* Special case if prog contains '/' */
if (strchr(prog, '/')) {
if ((stat(prog, &sbuf) == 0) && S_ISREG(sbuf.st_mode) &&
access(prog, X_OK) == 0) {
(void)puts(prog);
return (1);
} else {
(void)printf("%s: Command not found.\n", prog);
return (0);
}
}
if ((path = strdup(path)) == NULL)
errx(1, "Can't allocate memory.");
pathcpy = path;
proglen = strlen(prog);
while ((p = strsep(&pathcpy, ":")) != NULL) {
if (*p == '\0')
p = ".";
plen = strlen(p);
while (p[plen-1] == '/')
p[--plen] = '\0'; /* strip trailing '/' */
if (plen + 1 + proglen >= sizeof(filename)) {
warnx("%s/%s: %s", p, prog, strerror(ENAMETOOLONG));
free(path);
return (0);
}
snprintf(filename, sizeof(filename), "%s/%s", p, prog);
if ((stat(filename, &sbuf) == 0) && S_ISREG(sbuf.st_mode) &&
access(filename, X_OK) == 0) {
(void)puts(filename);
rval = 1;
if (!allmatches) {
free(path);
return (rval);
}
}
}
(void)free(path);
/* whereis(1) is silent on failure. */
if (!rval && progmode != PROG_WHEREIS)
(void)printf("%s: Command not found.\n", prog);
return (rval);
}
__dead void
usage(void)
{
(void) fprintf(stderr, "Usage: %s [-a] name [...]\n", __progname);
exit(1);
}
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