util.c revision 7165 
1/*-
2 * Copyright (c) 1992, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	$Id: util.c,v 1.2 1994/09/24 02:56:57 davidg Exp $
34 */
35
36#ifndef lint
37static char sccsid[] = "@(#)util.c	8.2 (Berkeley) 4/2/94";
38#endif /* not lint */
39
40#include <sys/param.h>
41#include <sys/stat.h>
42#include <sys/wait.h>
43
44#include <ctype.h>
45#include <err.h>
46#include <errno.h>
47#include <paths.h>
48#include <signal.h>
49#include <stdio.h>
50#include <stdlib.h>
51#include <string.h>
52#include <unistd.h>
53
54#include "extern.h"
55
56char *
57colon(cp)
58	char *cp;
59{
60	if (*cp == ':')		/* Leading colon is part of file name. */
61		return (0);
62
63	for (; *cp; ++cp) {
64		if (*cp == ':')
65			return (cp);
66		if (*cp == '/')
67			return (0);
68	}
69	return (0);
70}
71
72void
73verifydir(cp)
74	char *cp;
75{
76	struct stat stb;
77
78	if (!stat(cp, &stb)) {
79		if (S_ISDIR(stb.st_mode))
80			return;
81		errno = ENOTDIR;
82	}
83	run_err("%s: %s", cp, strerror(errno));
84	exit(1);
85}
86
87int
88okname(cp0)
89	char *cp0;
90{
91	int c;
92	char *cp;
93
94	cp = cp0;
95	do {
96		c = *cp;
97		if (c & 0200)
98			goto bad;
99		if (!isalpha(c) && !isdigit(c) && c != '_' && c != '-')
100			goto bad;
101	} while (*++cp);
102	return (1);
103
104bad:	warnx("%s: invalid user name", cp0);
105	return (0);
106}
107
108int
109susystem(s, userid)
110	int userid;
111	char *s;
112{
113	sig_t istat, qstat;
114	int status;
115	pid_t pid;
116
117	pid = vfork();
118	switch (pid) {
119	case -1:
120		return (127);
121
122	case 0:
123		(void)setuid(userid);
124		execl(_PATH_BSHELL, "sh", "-c", s, NULL);
125		_exit(127);
126	}
127	istat = signal(SIGINT, SIG_IGN);
128	qstat = signal(SIGQUIT, SIG_IGN);
129	if (waitpid(pid, &status, 0) < 0)
130		status = -1;
131	(void)signal(SIGINT, istat);
132	(void)signal(SIGQUIT, qstat);
133	return (status);
134}
135
136BUF *
137allocbuf(bp, fd, blksize)
138	BUF *bp;
139	int fd, blksize;
140{
141	struct stat stb;
142	size_t size;
143
144	if (fstat(fd, &stb) < 0) {
145		run_err("fstat: %s", strerror(errno));
146		return (0);
147	}
148	size = roundup(stb.st_blksize, blksize);
149	if (size == 0)
150		size = blksize;
151	if (bp->cnt >= size)
152		return (bp);
153	if ((bp->buf = realloc(bp->buf, size)) == NULL) {
154		bp->cnt = 0;
155		run_err("%s", strerror(errno));
156		return (0);
157	}
158	bp->cnt = size;
159	return (bp);
160}
161
162void
163lostconn(signo)
164	int signo;
165{
166	if (!iamremote)
167		warnx("lost connection");
168	exit(1);
169}
170