usr/src/cmd/mail/pipletr.c

   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, 1986, 1987, 1988, 1989 AT&T */
  28 /*        All Rights Reserved   */
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 #include "mail.h"
  33
  34 int
  35 dowait(pid_t pidval)
  36 {
  37         pid_t w;
  38         int status;
  39         void (*istat)(), (*qstat)();
  40
  41         /*
  42                 Parent temporarily ignores signals so it will remain
  43                 around for command to finish
  44         */
  45         istat = signal(SIGINT, SIG_IGN);
  46         qstat = signal(SIGQUIT, SIG_IGN);
  47
  48         while ((w = wait(&status)) != pidval && w != CERROR);
  49         if (w == CERROR) {
  50                 status = -errno;
  51                 signal(SIGINT, istat);
  52                 signal(SIGQUIT, qstat);
  53                 return (status);
  54         }
  55
  56         signal(SIGINT, istat);
  57         signal(SIGQUIT, qstat);
  58         status = ((status>>8)&0xFF);            /* extract 8 high order bits */
  59         return (status);
  60 }
  61
  62 /*
  63         invoke shell to execute command waiting for command to terminate
  64                 s       -> command string
  65         return:
  66                 status  -> command exit status
  67 */
  68 int
  69 systm(char *s)
  70 {
  71         pid_t   pid;
  72
  73         /*
  74                 Spawn the shell to execute command, however, since the
  75                 mail command runs setgid mode reset the effective group
  76                 id to the real group id so that the command does not
  77                 acquire any special privileges
  78         */
  79         if ((pid = fork()) == CHILD) {
  80                 setuid(my_uid);
  81                 setgid(my_gid);
  82 #ifdef SVR3
  83                 execl("/bin/sh", "sh", "-c", s, NULL);
  84 #else
  85                 execl("/usr/bin/sh", "sh", "-c", s, NULL);
  86 #endif
  87                 exit(127);
  88         }
  89         return (dowait(pid));
  90 }