xref: /netbsd-src/usr.bin/mkdep/findcc.c (revision 1c89b83dd464d704e1d3c9e71ad026804cea137f)
1 /* $NetBSD: findcc.c,v 1.10 2021/08/20 06:36:10 rillig Exp $ */
2 
3 /*-
4  * Copyright (c) 1999 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Matthias Scheler.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #if HAVE_NBTOOL_CONFIG_H
33 #include "nbtool_config.h"
34 #endif
35 
36 #include <sys/cdefs.h>
37 #if !defined(lint)
38 __COPYRIGHT("@(#) Copyright (c) 1999 The NetBSD Foundation, Inc.\
39  All rights reserved.");
40 __RCSID("$NetBSD: findcc.c,v 1.10 2021/08/20 06:36:10 rillig Exp $");
41 #endif /* not lint */
42 
43 #include <sys/param.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include "findcc.h"
50 
51 char *
findcc(const char * progname)52 findcc(const char *progname)
53 {
54 	char *cc;
55 	const char *path, *dir;
56 	char buffer[MAXPATHLEN];
57 	size_t progname_len, dir_len;
58 
59 	progname_len = strcspn(progname, " ");
60 
61 	if (memchr(progname, '/', progname_len) != NULL) {
62 		if ((cc = strndup(progname, progname_len)) == NULL)
63 			return NULL;
64 		if (access(cc, X_OK) == 0)
65 			return cc;
66 		free(cc);
67 		return NULL;
68 	}
69 
70 	if ((path = getenv("PATH")) == NULL)
71 		return NULL;
72 
73 	for (dir = path; *dir != '\0'; ) {
74 		dir_len = strcspn(dir, ":");
75 
76 		if ((size_t)snprintf(buffer, sizeof(buffer), "%.*s/%.*s",
77 			(int)dir_len, dir, (int)progname_len, progname)
78 		    < sizeof(buffer)
79 		    && access(buffer, X_OK) == 0)
80 			return strdup(buffer);
81 
82 		dir += dir_len;
83 		if (*dir == ':')
84 			dir++;
85 	}
86 
87 	return NULL;
88 }
89