xref: /dragonfly/usr.sbin/lpr/common_source/startdaemon.c (revision c81991eda56a474436edcae2c94488ec9e677aff)
1 /*
2  * Copyright (c) 1983, 1993, 1994
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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)startdaemon.c          8.2 (Berkeley) 4/17/94
30  * $FreeBSD: src/usr.sbin/lpr/common_source/startdaemon.c,v 1.8.2.2 2002/04/26 18:24:40 gad Exp $
31  * $DragonFly: src/usr.sbin/lpr/common_source/startdaemon.c,v 1.4 2004/12/18 22:48:03 swildner Exp $
32  */
33 
34 #include <sys/param.h>
35 #include <sys/socket.h>
36 #include <sys/uio.h>
37 #include <sys/un.h>
38 
39 #include <dirent.h>
40 #include <err.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <unistd.h>
44 #include "lp.h"
45 #include "pathnames.h"
46 
47 extern uid_t        uid, euid;
48 
49 /*
50  * Tell the printer daemon that there are new files in the spool directory.
51  */
52 
53 int
startdaemon(const struct printer * pp)54 startdaemon(const struct printer *pp)
55 {
56           struct sockaddr_un un;
57           int s, n;
58           int connectres;
59           char c;
60 
61           s = socket(PF_LOCAL, SOCK_STREAM, 0);
62           if (s < 0) {
63                     warn("socket");
64                     return(0);
65           }
66           memset(&un, 0, sizeof(un));
67           un.sun_family = AF_LOCAL;
68           strcpy(un.sun_path, _PATH_SOCKETNAME);
69 #ifndef SUN_LEN
70 #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2)
71 #endif
72           seteuid(euid);
73           connectres = connect(s, (struct sockaddr *)&un, SUN_LEN(&un));
74           seteuid(uid);
75           if (connectres < 0) {
76                     warn("Unable to connect to %s", _PATH_SOCKETNAME);
77                     warnx("Check to see if the master 'lpd' process is running.");
78                     close(s);
79                     return(0);
80           }
81 
82           /*
83            * Avoid overruns without putting artificial limitations on
84            * the length.
85            */
86           if (writel(s, "\1", pp->printer, "\n", NULL) <= 0) {
87                     warn("write");
88                     close(s);
89                     return(0);
90           }
91           if (read(s, &c, 1) == 1) {
92                     if (c == '\0') {              /* everything is OK */
93                               close(s);
94                               return(1);
95                     }
96                     putchar(c);
97           }
98           while ((n = read(s, &c, 1)) > 0)
99                     putchar(c);
100           close(s);
101           return(0);
102 }
103