usr.sbin/lpr/common_source/startdaemon.c

   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. 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  * @(#)startdaemon.c    8.2 (Berkeley) 4/17/94
  34  * $FreeBSD: src/usr.sbin/lpr/common_source/startdaemon.c,v 1.8.2.2 2002/04/26 18:24:40 gad Exp $
  35  * $DragonFly: src/usr.sbin/lpr/common_source/startdaemon.c,v 1.4 2004/12/18 22:48:03 swildner Exp $
  36  */
  37
  38 #include <sys/param.h>
  39 #include <sys/socket.h>
  40 #include <sys/uio.h>
  41 #include <sys/un.h>
  42
  43 #include <dirent.h>
  44 #include <err.h>
  45 #include <stdio.h>
  46 #include <string.h>
  47 #include <unistd.h>
  48 #include "lp.h"
  49 #include "pathnames.h"
  50
  51 extern uid_t    uid, euid;
  52
  53 /*
  54  * Tell the printer daemon that there are new files in the spool directory.
  55  */
  56
  57 int
  58 startdaemon(const struct printer *pp)
  59 {
  60         struct sockaddr_un un;
  61         int s, n;
  62         int connectres;
  63         char c;
  64
  65         s = socket(PF_LOCAL, SOCK_STREAM, 0);
  66         if (s < 0) {
  67                 warn("socket");
  68                 return(0);
  69         }
  70         memset(&un, 0, sizeof(un));
  71         un.sun_family = AF_LOCAL;
  72         strcpy(un.sun_path, _PATH_SOCKETNAME);
  73 #ifndef SUN_LEN
  74 #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2)
  75 #endif
  76         seteuid(euid);
  77         connectres = connect(s, (struct sockaddr *)&un, SUN_LEN(&un));
  78         seteuid(uid);
  79         if (connectres < 0) {
  80                 warn("Unable to connect to %s", _PATH_SOCKETNAME);
  81                 warnx("Check to see if the master 'lpd' process is running.");
  82                 close(s);
  83                 return(0);
  84         }
  85
  86         /*
  87          * Avoid overruns without putting artificial limitations on
  88          * the length.
  89          */
  90         if (writel(s, "\1", pp->printer, "\n", NULL) <= 0) {
  91                 warn("write");
  92                 close(s);
  93                 return(0);
  94         }
  95         if (read(s, &c, 1) == 1) {
  96                 if (c == '\0') {                /* everything is OK */
  97                         close(s);
  98                         return(1);
  99                 }
 100                 putchar(c);
 101         }
 102         while ((n = read(s, &c, 1)) > 0)
 103                 putchar(c);
 104         close(s);
 105         return(0);
 106 }