shadow/lib/spawn.c
Thomas Abraham 82fa6eccf9 lib/spawn.c run_command: don't loop forever if waitpid() is returning ECHILD
If SIGCHILD is being ignored, waitpid() will forever error with ECHILD and
this loop with never end, so don't loop if it errors with ECHILD.
2019-05-06 14:26:14 -04:00

85 lines
2.7 KiB
C

/*
* Copyright (c) 2011 , Jonathan Nieder
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the copyright holders or contributors may not be used to
* endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <config.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include "exitcodes.h"
#include "prototypes.h"
int run_command (const char *cmd, const char *argv[],
/*@null@*/const char *envp[], /*@out@*/int *status)
{
pid_t pid, wpid;
if (NULL == envp) {
envp = (const char **)environ;
}
(void) fflush (stdout);
(void) fflush (stderr);
pid = fork ();
if (0 == pid) {
(void) execve (cmd, (char * const *) argv,
(char * const *) envp);
if (ENOENT == errno) {
exit (E_CMD_NOTFOUND);
}
fprintf (stderr, "%s: cannot execute %s: %s\n",
Prog, cmd, strerror (errno));
exit (E_CMD_NOEXEC);
} else if ((pid_t)-1 == pid) {
fprintf (stderr, "%s: cannot execute %s: %s\n",
Prog, cmd, strerror (errno));
return -1;
}
do {
wpid = waitpid (pid, status, 0);
if ((pid_t)-1 == wpid && errno == ECHILD)
break;
} while ( ((pid_t)-1 == wpid && errno == EINTR)
|| ((pid_t)-1 != wpid && wpid != pid));
if ((pid_t)-1 == wpid) {
fprintf (stderr, "%s: waitpid (status: %d): %s\n",
Prog, *status, strerror (errno));
return -1;
}
return 0;
}