util.c revision 1557 
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
34#ifndef lint
35static char sccsid[] = "@(#)util.c	8.2 (Berkeley) 4/2/94";
36#endif /* not lint */
37
38#include <sys/param.h>
39#include <sys/stat.h>
40#include <sys/wait.h>
41
42#include <ctype.h>
43#include <err.h>
44#include <errno.h>
45#include <paths.h>
46#include <signal.h>
47#include <stdio.h>
48#include <stdlib.h>
49#include <string.h>
50#include <unistd.h>
51
52#include "extern.h"
53
54char *
55colon(cp)
56	char *cp;
57{
58	if (*cp == ':')		/* Leading colon is part of file name. */
59		return (0);
60
61	for (; *cp; ++cp) {
62		if (*cp == ':')
63			return (cp);
64		if (*cp == '/')
65			return (0);
66	}
67	return (0);
68}
69
70void
71verifydir(cp)
72	char *cp;
73{
74	struct stat stb;
75
76	if (!stat(cp, &stb)) {
77		if (S_ISDIR(stb.st_mode))
78			return;
79		errno = ENOTDIR;
80	}
81	run_err("%s: %s", cp, strerror(errno));
82	exit(1);
83}
84
85int
86okname(cp0)
87	char *cp0;
88{
89	int c;
90	char *cp;
91
92	cp = cp0;
93	do {
94		c = *cp;
95		if (c & 0200)
96			goto bad;
97		if (!isalpha(c) && !isdigit(c) && c != '_' && c != '-')
98			goto bad;
99	} while (*++cp);
100	return (1);
101
102bad:	warnx("%s: invalid user name", cp0);
103	return (0);
104}
105
106int
107susystem(s, userid)
108	int userid;
109	char *s;
110{
111	sig_t istat, qstat;
112	int status, w;
113	pid_t pid;
114
115	pid = vfork();
116	switch (pid) {
117	case -1:
118		return (127);
119
120	case 0:
121		(void)setuid(userid);
122		execl(_PATH_BSHELL, "sh", "-c", s, NULL);
123		_exit(127);
124	}
125	istat = signal(SIGINT, SIG_IGN);
126	qstat = signal(SIGQUIT, SIG_IGN);
127	if (waitpid(pid, &status, 0) < 0)
128		status = -1;
129	(void)signal(SIGINT, istat);
130	(void)signal(SIGQUIT, qstat);
131	return (status);
132}
133
134BUF *
135allocbuf(bp, fd, blksize)
136	BUF *bp;
137	int fd, blksize;
138{
139	struct stat stb;
140	size_t size;
141
142	if (fstat(fd, &stb) < 0) {
143		run_err("fstat: %s", strerror(errno));
144		return (0);
145	}
146	size = roundup(stb.st_blksize, blksize);
147	if (size == 0)
148		size = blksize;
149	if (bp->cnt >= size)
150		return (bp);
151	if ((bp->buf = realloc(bp->buf, size)) == NULL) {
152		bp->cnt = 0;
153		run_err("%s", strerror(errno));
154		return (0);
155	}
156	bp->cnt = size;
157	return (bp);
158}
159
160void
161lostconn(signo)
162	int signo;
163{
164	if (!iamremote)
165		warnx("lost connection");
166	exit(1);
167}
168