compat/lib/system.c

   1 /*
   2  *      Ported to Linux's Second Extended File System as part of the
   3  *      dump and restore backup suit
   4  *      Remy Card <card@Linux.EU.Org>, 1994-1997
   5  *      Stelian Pop <pop@noos.fr>, 1999-2000
   6  *      Stelian Pop <pop@noos.fr> - Alcôve <www.alcove.fr>, 2000
   7  */
   8
   9 /*-
  10  * Copyright (c) 1980, 1991, 1993
  11  *      The Regents of the University of California.  All rights reserved.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions and the following disclaimer.
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  * 3. All advertising materials mentioning features or use of this software
  22  *    must display the following acknowledgement:
  23  *      This product includes software developed by the University of
  24  *      California, Berkeley and its contributors.
  25  * 4. Neither the name of the University nor the names of its contributors
  26  *    may be used to endorse or promote products derived from this software
  27  *    without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  39  * SUCH DAMAGE.
  40  */
  41
  42 #ifndef lint
  43 static const char rcsid[] =
  44         "$Id: system.c,v 1.2 2001/08/13 16:17:52 stelian Exp $";
  45 #endif /* not lint */
  46
  47 #include <config.h>
  48 #include <errno.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <unistd.h>
  53 #include <sys/types.h>
  54 #include <sys/wait.h>
  55 #include "system.h"
  56
  57 /*
  58  * Executes the command in a shell.
  59  * Returns -1 if an error occured, the exit status of
  60  * the command on success.
  61  */
  62 int system_command(const char *command, const char *device, int volnum) {
  63         int pid, status;
  64         char commandstr[4096];
  65
  66         pid = fork();
  67         if (pid == -1) {
  68                 perror("  DUMP: unable to fork");
  69                 return -1;
  70         }
  71         if (pid == 0) {
  72                 setuid(getuid());
  73                 setgid(getgid());
  74 #if OLD_STYLE_FSCRIPT
  75                 snprintf(commandstr, sizeof(commandstr), "%s", command);
  76 #else
  77                 snprintf(commandstr, sizeof(commandstr), "%s %s %d", command, device, volnum);
  78 #endif
  79                 commandstr[sizeof(commandstr) - 1] = '\0';
  80                 execl("/bin/sh", "sh", "-c", commandstr, NULL);
  81                 perror("unable to execute shell");
  82                 exit(-1);
  83         }
  84         do {
  85                 if (waitpid(pid, &status, 0) == -1) {
  86                         if (errno != EINTR) {
  87                                 perror("waitpid error");
  88                                 return -1;
  89                         }
  90                 } else {
  91                         if (WIFEXITED(status))
  92                                 return WEXITSTATUS(status);
  93                         else
  94                                 return -1;
  95                 }
  96         } while(1);
  97 }
  98