external/gpl2/lvm2/dist/lib/misc/lvm-exec.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
   5  * Copyright (C) 2004-2009 Red Hat, Inc. All rights reserved.
   6  *
   7  * This file is part of LVM2.
   8  *
   9  * This copyrighted material is made available to anyone wishing to use,
  10  * modify, copy, or redistribute it subject to the terms and conditions
  11  * of the GNU Lesser General Public License v.2.1.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public License
  14  * along with this program; if not, write to the Free Software Foundation,
  15  * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16  */
  17
  18 #include "lib.h"
  19 #include "device.h"
  20 #include "locking.h"
  21 #include "lvm-exec.h"
  22 #include "toolcontext.h"
  23
  24 #include <unistd.h>
  25 #include <sys/wait.h>
  26
  27 /*
  28  * Create verbose string with list of parameters
  29  */
  30 static char *_verbose_args(const char *const argv[], char *buf, size_t sz)
  31 {
  32         int pos = 0;
  33         int len;
  34         unsigned i;
  35
  36         buf[0] = '\0';
  37         for (i = 0; argv[i]; i++) {
  38                 if ((len = dm_snprintf(buf + pos, sz - pos,
  39                                        "%s ", argv[i])) < 0)
  40                         /* Truncated */
  41                         break;
  42                 pos += len;
  43         }
  44
  45         return buf;
  46 }
  47
  48 /*
  49  * Execute and wait for external command
  50  */
  51 int exec_cmd(struct cmd_context *cmd, const char *const argv[])
  52 {
  53         pid_t pid;
  54         int status;
  55         char buf[PATH_MAX * 2];
  56
  57         log_verbose("Executing: %s", _verbose_args(argv, buf, sizeof(buf)));
  58
  59         if ((pid = fork()) == -1) {
  60                 log_error("fork failed: %s", strerror(errno));
  61                 return 0;
  62         }
  63
  64         if (!pid) {
  65                 /* Child */
  66                 reset_locking();
  67                 dev_close_all();
  68                 /* FIXME Fix effect of reset_locking on cache then include this */
  69                 /* destroy_toolcontext(cmd); */
  70                 /* FIXME Use execve directly */
  71                 execvp(argv[0], (char **const) argv);
  72                 log_sys_error("execvp", argv[0]);
  73                 _exit(errno);
  74         }
  75
  76         /* Parent */
  77         if (wait4(pid, &status, 0, NULL) != pid) {
  78                 log_error("wait4 child process %u failed: %s", pid,
  79                           strerror(errno));
  80                 return 0;
  81         }
  82
  83         if (!WIFEXITED(status)) {
  84                 log_error("Child %u exited abnormally", pid);
  85                 return 0;
  86         }
  87
  88         if (WEXITSTATUS(status)) {
  89                 log_error("%s failed: %u", argv[0], WEXITSTATUS(status));
  90                 return 0;
  91         }
  92
  93         return 1;
  94 }