[apple/shell_cmds.git] / which / which.c

/**
 * Copyright (c) 2000 Dan Papasian.  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.
 * 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: src/usr.bin/which/which.c,v 1.6 2005/02/10 16:04:22 ru Exp $");

#include <sys/stat.h>
#include <sys/param.h>

#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static void	 usage(void);
static int	 print_matches(char *, char *);
	
int 	silent;
int 	allpaths;

int
main(int argc, char **argv)
{
	char *p, *path;
	ssize_t pathlen;
	int opt, status;

	status = EXIT_SUCCESS;

	while ((opt = getopt(argc, argv, "as")) != -1) {
		switch (opt) {
		case 'a':
			allpaths = 1;
			break;
		case 's':
			silent = 1;
			break;
		default:
			usage();
			break;
		}
	}

	argv += optind;
	argc -= optind;

	if (argc == 0)
		usage();

	if ((p = getenv("PATH")) == NULL)
		exit(EXIT_FAILURE);
	pathlen = strlen(p) + 1;
	path = malloc(pathlen);
	if (path == NULL)
		err(EXIT_FAILURE, NULL);

	while (argc > 0) {
		memcpy(path, p, pathlen);
	
		if (strlen(*argv) >= FILENAME_MAX ||
		    print_matches(path, *argv) == -1)
			status = EXIT_FAILURE;

		argv++;
		argc--;
	}

	exit(status);
}

static void
usage(void)
{

	(void)fprintf(stderr, "usage: which [-as] program ...\n");
	exit(EXIT_FAILURE);
}

static int
is_there(char *candidate)
{
	struct stat fin;

	/* XXX work around access(2) false positives for superuser */
	if (access(candidate, X_OK) == 0 &&
	    stat(candidate, &fin) == 0 &&
	    S_ISREG(fin.st_mode) &&
	    (getuid() != 0 ||
	    (fin.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0)) {
		if (!silent)
			printf("%s\n", candidate);
		return (1);
	}
	return (0);
}

static int
print_matches(char *path, char *filename)
{
	char candidate[PATH_MAX];
	const char *d;
	int found;

	if (strchr(filename, '/') != NULL)
		return (is_there(filename) ? 0 : -1);
	found = 0;
	while ((d = strsep(&path, ":")) != NULL) {
		if (*d == '\0')
			d = ".";
		if (snprintf(candidate, sizeof(candidate), "%s/%s", d,
		    filename) >= (int)sizeof(candidate))
			continue;
		if (is_there(candidate)) {
			found = 1;
			if (!allpaths)
				break;
		}
	}
	return (found ? 0 : -1);
}
Commit	Line	Data
e1a085ba A	1	/**
	2	* Copyright (c) 2000 Dan Papasian. All rights reserved.
	3	*
	4	* Redistribution and use in source and binary forms, with or without
	5	* modification, are permitted provided that the following conditions
	6	* are met:
	7	* 1. Redistributions of source code must retain the above copyright
	8	* notice, this list of conditions and the following disclaimer.
	9	* 2. Redistributions in binary form must reproduce the above copyright
	10	* notice, this list of conditions and the following disclaimer in the
	11	* documentation and/or other materials provided with the distribution.
	12	* 3. The name of the author may not be used to endorse or promote products
	13	* derived from this software without specific prior written permission.
	14	*
	15	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	16	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	17	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	18	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	19	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	20	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	21	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	22	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	23	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	24	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	25	*/
	26
	27	#include <sys/cdefs.h>
	28
	29	__FBSDID("$FreeBSD: src/usr.bin/which/which.c,v 1.6 2005/02/10 16:04:22 ru Exp $");
	30
	31	#include <sys/stat.h>
	32	#include <sys/param.h>
	33
	34	#include <err.h>
	35	#include <stdio.h>
	36	#include <stdlib.h>
	37	#include <string.h>
	38	#include <unistd.h>
	39
	40	static void usage(void);
	41	static int print_matches(char , char );
	42
	43	int silent;
	44	int allpaths;
	45
	46	int
	47	main(int argc, char **argv)
	48	{
	49	char p, path;
	50	ssize_t pathlen;
	51	int opt, status;
	52
	53	status = EXIT_SUCCESS;
	54
	55	while ((opt = getopt(argc, argv, "as")) != -1) {
	56	switch (opt) {
	57	case 'a':
	58	allpaths = 1;
	59	break;
	60	case 's':
	61	silent = 1;
	62	break;
	63	default:
	64	usage();
65	break;
66	}
67	}
68
69	argv += optind;
70	argc -= optind;
71
72	if (argc == 0)
73	usage();
74
75	if ((p = getenv("PATH")) == NULL)
76	exit(EXIT_FAILURE);
77	pathlen = strlen(p) + 1;
78	path = malloc(pathlen);
79	if (path == NULL)
80	err(EXIT_FAILURE, NULL);
81
82	while (argc > 0) {
83	memcpy(path, p, pathlen);
84
85	if (strlen(*argv) >= FILENAME_MAX \|\|
86	print_matches(path, *argv) == -1)
87	status = EXIT_FAILURE;
88
89	argv++;
90	argc--;
91	}
92
93	exit(status);
94	}
95
96	static void
97	usage(void)
98	{
99
100	(void)fprintf(stderr, "usage: which [-as] program ...\n");
101	exit(EXIT_FAILURE);
102	}
103
104	static int
105	is_there(char *candidate)
106	{
107	struct stat fin;
108
109	/* XXX work around access(2) false positives for superuser */
110	if (access(candidate, X_OK) == 0 &&
111	stat(candidate, &fin) == 0 &&
112	S_ISREG(fin.st_mode) &&
113	(getuid() != 0 \|\|
114	(fin.st_mode & (S_IXUSR \| S_IXGRP \| S_IXOTH)) != 0)) {
115	if (!silent)
116	printf("%s\n", candidate);
117	return (1);
118	}
119	return (0);
120	}
121
122	static int
123	print_matches(char path, char filename)
124	{
125	char candidate[PATH_MAX];
126	const char *d;
127	int found;
128
129	if (strchr(filename, '/') != NULL)
130	return (is_there(filename) ? 0 : -1);
131	found = 0;
132	while ((d = strsep(&path, ":")) != NULL) {
133	if (*d == '\0')
134	d = ".";
135	if (snprintf(candidate, sizeof(candidate), "%s/%s", d,
136	filename) >= (int)sizeof(candidate))
137	continue;
138	if (is_there(candidate)) {
139	found = 1;
140	if (!allpaths)
141	break;
142	}
143	}
144	return (found ? 0 : -1);
145	}
146