163 lines
4.0 KiB
Diff
163 lines
4.0 KiB
Diff
diff --git a/src/posix_spawn.c b/src/posix_spawn.c
|
|
new file mode 100644
|
|
index 0000000..18ceb06
|
|
--- /dev/null
|
|
+++ b/src/posix_spawn.c
|
|
@@ -0,0 +1,156 @@
|
|
+/*
|
|
+ * dhcpcd - DHCP client daemon
|
|
+ * Copyright (c) 2006-2012 Roy Marples <roy@marples.name>
|
|
+ * 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.
|
|
+ *
|
|
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
+ */
|
|
+
|
|
+/* This implementation of posix_spawn is only suitable for the needs of dhcpcd
|
|
+ * but it could easily be extended to other applications. */
|
|
+
|
|
+#include <sys/types.h>
|
|
+#include <sys/wait.h>
|
|
+
|
|
+#include <errno.h>
|
|
+#include <signal.h>
|
|
+#include <stdlib.h>
|
|
+#include <string.h>
|
|
+#include <unistd.h>
|
|
+
|
|
+#include "posix_spawn.h"
|
|
+
|
|
+#ifndef _NSIG
|
|
+#ifdef _SIG_MAXSIG
|
|
+#define _NSIG _SIG_MAXSIG + 1
|
|
+#else
|
|
+/* Guess */
|
|
+#define _NSIG SIGPWR + 1
|
|
+#endif
|
|
+#endif
|
|
+
|
|
+extern char **environ;
|
|
+
|
|
+static int
|
|
+posix_spawnattr_handle(const posix_spawnattr_t *attrp)
|
|
+{
|
|
+ struct sigaction sa;
|
|
+ int i;
|
|
+
|
|
+ if (attrp->posix_attr_flags & POSIX_SPAWN_SETSIGMASK)
|
|
+ sigprocmask(SIG_SETMASK, &attrp->posix_attr_sigmask, NULL);
|
|
+
|
|
+ if (attrp->posix_attr_flags & POSIX_SPAWN_SETSIGDEF) {
|
|
+ memset(&sa, 0, sizeof(sa));
|
|
+ sa.sa_handler = SIG_DFL;
|
|
+ for (i = 1; i < _NSIG; i++) {
|
|
+ if (sigismember(&attrp->posix_attr_sigdefault, i)) {
|
|
+ if (sigaction(i, &sa, NULL) == -1)
|
|
+ return -1;
|
|
+ }
|
|
+ }
|
|
+ }
|
|
+
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+inline static int
|
|
+is_vfork_safe(short int flags)
|
|
+{
|
|
+ return !(flags & (POSIX_SPAWN_SETSIGDEF | POSIX_SPAWN_SETSIGMASK));
|
|
+}
|
|
+
|
|
+int
|
|
+posix_spawn(pid_t *pid, const char *path,
|
|
+ const posix_spawn_file_actions_t *file_actions,
|
|
+ const posix_spawnattr_t *attrp,
|
|
+ char *const argv[], char *const envp[])
|
|
+{
|
|
+ short int flags;
|
|
+ pid_t p;
|
|
+ volatile int error;
|
|
+
|
|
+ error = 0;
|
|
+ flags = attrp ? attrp->posix_attr_flags : 0;
|
|
+ if (file_actions == NULL && is_vfork_safe(flags))
|
|
+ p = vfork();
|
|
+ else
|
|
+#ifdef THERE_IS_NO_FORK
|
|
+ return ENOSYS;
|
|
+#else
|
|
+ p = fork();
|
|
+#endif
|
|
+ switch (p) {
|
|
+ case -1:
|
|
+ return errno;
|
|
+ case 0:
|
|
+ if (attrp) {
|
|
+ error = posix_spawnattr_handle(attrp);
|
|
+ if (error)
|
|
+ _exit(127);
|
|
+ }
|
|
+ execve(path, argv, envp);
|
|
+ error = errno;
|
|
+ _exit(127);
|
|
+ default:
|
|
+ if (error != 0)
|
|
+ waitpid(p, NULL, WNOHANG);
|
|
+ else if (pid != NULL)
|
|
+ *pid = p;
|
|
+ return error;
|
|
+ }
|
|
+}
|
|
+
|
|
+int
|
|
+posix_spawnattr_init(posix_spawnattr_t *attr)
|
|
+{
|
|
+
|
|
+ memset(attr, 0, sizeof(*attr));
|
|
+ attr->posix_attr_flags = 0;
|
|
+ sigprocmask(0, NULL, &attr->posix_attr_sigmask);
|
|
+ sigemptyset(&attr->posix_attr_sigdefault);
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+int
|
|
+posix_spawnattr_setflags(posix_spawnattr_t *attr, short flags)
|
|
+{
|
|
+
|
|
+ attr->posix_attr_flags = flags;
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+int
|
|
+posix_spawnattr_setsigmask(posix_spawnattr_t *attr, const sigset_t *sigmask)
|
|
+{
|
|
+
|
|
+ attr->posix_attr_sigmask = *sigmask;
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+int
|
|
+posix_spawnattr_setsigdefault(posix_spawnattr_t *attr, const sigset_t *sigmask)
|
|
+{
|
|
+
|
|
+ attr->posix_attr_sigdefault = *sigmask;
|
|
+ return 0;
|
|
+}
|