xref: /titanic_41/usr/src/lib/libbc/libc/gen/common/execvp.c (revision ea394cb00fd96864e34d2841b4a22357b621c78f)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*      Copyright (c) 1984 AT&T */
28 /*        All Rights Reserved   */
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*LINTLIBRARY*/
33 /*
34  *	execlp(name, arg,...,0)	(like execl, but does path search)
35  *	execvp(name, argv)	(like execv, but does path search)
36  */
37 #include <errno.h>
38 #include <sys/param.h>
39 #include <stdarg.h>
40 #include <string.h>
41 #include <stdlib.h>
42 #include <unistd.h>
43 
44 static char *execat(char *, char *, char *);
45 static char *shell = "/bin/sh";
46 
47 int
48 execlp(char *name, ...)
49 {
50 	va_list	args;
51 	int	r;
52 
53 	va_start(args, name);
54 	r = execvp(name, (char **)args);
55 	va_end(args);
56 
57 	return (r);
58 }
59 
60 int
61 execvp(char *name, char **argv)
62 {
63 	char	*pathstr;
64 	char	fname[MAXPATHLEN];
65 	char	*newargs[256];
66 	int	i;
67 	char	*cp;
68 	unsigned etxtbsy = 1;
69 	int	eacces = 0;
70 
71 	if ((pathstr = getenv("PATH")) == NULL)
72 		pathstr = ":/usr/ucb:/bin:/usr/bin";
73 	cp = strchr(name, '/') ? "": pathstr;
74 
75 	do {
76 		cp = execat(cp, name, fname);
77 	retry:
78 		(void) execv(fname, argv);
79 		switch (errno) {
80 		case ENOEXEC:
81 			newargs[0] = "sh";
82 			newargs[1] = fname;
83 			for (i = 1; (newargs[i+1] = argv[i]) != NULL; ++i) {
84 				if (i >= 254) {
85 					errno = E2BIG;
86 					return(-1);
87 				}
88 			}
89 			(void) execv(shell, newargs);
90 			return (-1);
91 		case ETXTBSY:
92 			if (++etxtbsy > 5)
93 				return (-1);
94 			(void) sleep(etxtbsy);
95 			goto retry;
96 		case EACCES:
97 			++eacces;
98 			break;
99 		case ENOMEM:
100 		case E2BIG:
101 		case EFAULT:
102 			return (-1);
103 		}
104 	} while (cp);
105 	if (eacces)
106 		errno = EACCES;
107 	return (-1);
108 }
109 
110 static char *
111 execat(char *s1, char *s2, char *si)
112 {
113 	char	*s;
114 	char	*end;
115 
116 	s = si;
117 	end = s + MAXPATHLEN;
118 	while (*s1 && *s1 != ':' && s < end)
119 		*s++ = *s1++;
120 	if (si != s && s < end)
121 		*s++ = '/';
122 	while (*s2 && s < end)
123 		*s++ = *s2++;
124 	*s = '\0';
125 	return (*s1 ? ++s1: 0);
126 }
127