--- /dev/null
+../../licenses/BSD
\ No newline at end of file
--- /dev/null
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * daemon_with_notify - daemonize a process, can wait for child to signal readiness
+ *
+ * Daemons should detach themselves thoroughly from the process which launched
+ * them, and not prevent any filesystems from being unmounted. daemonize()
+ * helps with the process.
+ *
+ * Daemon-with-notify is different in that the child can send a SIGUSR1 to
+ * the parent to indicate it has started (e.g. after memory allocation and
+ * other things that may fail) so that the parent can return a success or
+ * failing exit code and init scripts can pick this up easily.
+ *
+ * Example:
+ * #include <ccan/daemon_with_notify/daemon_with_notify.h>
+ * #include <ccan/str/str.h>
+ * #include <err.h>
+ * #include <unistd.h>
+ * #include <stdlib.h>
+ *
+ * static void usage(const char *name)
+ * {
+ * errx(1, "Usage: %s [--daemonize]\n", name);
+ * }
+ *
+ * // Wait for a minute, possibly as a daemon.
+ * int main(int argc, char *argv[])
+ * {
+ * if (argc != 1) {
+ * if (argc == 2 && streq(argv[1], "--daemonize")) {
+ * if (!daemonize(1, 1, 1))
+ * err(1, "Failed to become daemon");
+ * } else
+ * usage(argv[1]);
+ * }
+ * sleep(10); // do some init here
+ * daemon_is_ready();
+ * sleep(20); // will be done in child, detached from parent
+ * exit(0);
+ * }
+ *
+ * License: BSD
+ * Author: Stewart Smith <stewart@flamingspork.com>
+ */
+int main(int argc, char *argv[])
+{
+ if (argc != 2)
+ return 1;
+
+ if (strcmp(argv[1], "depends") == 0) {
+ return 0;
+ }
+
+ if (strcmp(argv[1], "libs") == 0) {
+ return 0;
+ }
+
+ return 1;
+}
+
--- /dev/null
+/*-
+ * Copyright (c) 1990, 1993
+ * The Regents of the University of California. All rights reserved.
+ * Copyright (c) 2010
+ * Stewart Smith
+ *
+ * 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. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/select.h>
+
+#include <ccan/daemon_with_notify/daemon_with_notify.h>
+
+void sigusr1_handler(int sig);
+
+pid_t parent_pid;
+
+void sigusr1_handler(int sig)
+{
+ if (sig == SIGUSR1)
+ _exit(EXIT_SUCCESS);
+}
+
+int daemon_is_ready(void)
+{
+ kill(parent_pid, SIGUSR1);
+ return 0;
+}
+
+int daemonize(int nochdir, int noclose, int wait_sigusr1)
+{
+ int fd;
+ pid_t child= -1;
+
+ parent_pid= getpid();
+ signal(SIGUSR1, sigusr1_handler);
+
+ child= fork();
+
+ switch (child)
+ {
+ case -1:
+ return (-1);
+ case 0:
+ break;
+ default:
+ if (wait_sigusr1)
+ {
+ /* parent */
+ int exit_code= -1;
+ int status;
+ while (waitpid(child, &status, 0) != child);
+ if (WIFEXITED(status))
+ {
+ exit_code= WEXITSTATUS(status);
+ }
+ if (WIFSIGNALED(status))
+ {
+ exit_code= -1;
+ }
+ _exit(exit_code);
+ }
+ else
+ {
+ _exit(EXIT_SUCCESS);
+ }
+ }
+
+ /* child */
+ if (setsid() == -1)
+ return (-1);
+
+ if (nochdir == 0) {
+ if(chdir("/") != 0) {
+ perror("chdir");
+ return (-1);
+ }
+ }
+
+ if (noclose == 0 && (fd = open("/dev/null", O_RDWR, 0)) != -1) {
+ if(dup2(fd, STDIN_FILENO) < 0) {
+ perror("dup2 stdin");
+ return (-1);
+ }
+ if(dup2(fd, STDOUT_FILENO) < 0) {
+ perror("dup2 stdout");
+ return (-1);
+ }
+ if(dup2(fd, STDERR_FILENO) < 0) {
+ perror("dup2 stderr");
+ return (-1);
+ }
+
+ if (fd > STDERR_FILENO) {
+ if(close(fd) < 0) {
+ perror("close");
+ return (-1);
+ }
+ }
+ }
+ return (0);
+}
--- /dev/null
+#ifndef CCAN_DAEMON_WITH_NOTIFY_H
+#define CCAN_DAEMON_WITH_NOTIFY_H
+
+/**
+ * daemonize - turns this process into a daemon
+ *
+ * This routine will fork() us off to become a daemon. It will return
+ * -1 on error and 0 on success.
+ *
+ * It has a few optional behaviours:
+ * @nochdir: if nochdir is set, it won't chdir to /
+ * this means we could hold onto mounts
+ * @noclose: if noclose is set, we won't close stdout, stdin and stderr.
+ * @wait_sigusr1: if wait_sigusr1 is set, the parent will not exit until the
+ * child has either exited OR it receives a SIGUSR1 signal. You can use this
+ * to have the parent only exit when your process has done all the
+ * danegerous initialization that could cause it to fail to start
+ * (e.g. allocating large amounts of memory, replaying REDO logs).
+ * This allows init scripts starting the daemon to easily report
+ * success/failure.
+ */
+int daemonize(int nochdir, int noclose, int wait_sigusr1);
+
+/**
+ * daemon_is_ready - signals parent that it can exit, we started okay
+ *
+ * After a daemonize() call, this function will send a SIGUSR1 to the parent
+ * telling it to exit as we have started up okay.
+ */
+int daemon_is_ready(void);
+
+#endif /* CCAN_DAEMON_WITH_NOTIFY_H */
--- /dev/null
+#include <ccan/daemon_with_notify/daemon_with_notify.h>
+#include <ccan/daemon_with_notify/daemon_with_notify.c>
+#include <ccan/tap/tap.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <err.h>
+#include <errno.h>
+#include <string.h>
+
+struct child_data {
+ pid_t pid;
+ pid_t ppid;
+ int in_root_dir;
+ int read_from_stdin, write_to_stdout, write_to_stderr;
+};
+
+int main(int argc, char *argv[])
+{
+ int fds[2];
+ struct child_data daemonized;
+ pid_t pid;
+
+ plan_tests(6);
+
+ if (pipe(fds) != 0)
+ err(1, "Failed pipe");
+
+ /* Since daemonize forks and parent exits, we need to fork
+ * that parent. */
+ pid = fork();
+ if (pid == -1)
+ err(1, "Failed fork");
+
+ if (pid == 0) {
+ char buffer[2];
+ pid = getpid();
+ daemonize(0, 0, 1);
+ daemon_is_ready();
+ /* Keep valgrind happy about uninitialized bytes. */
+ memset(&daemonized, 0, sizeof(daemonized));
+ daemonized.pid = getpid();
+ daemonized.in_root_dir = (getcwd(buffer, 2) != NULL);
+ daemonized.read_from_stdin
+ = read(STDIN_FILENO, buffer, 1) == -1 ? errno : 0;
+ daemonized.write_to_stdout
+ = write(STDOUT_FILENO, buffer, 1) == -1 ? errno : 0;
+ if (write(STDERR_FILENO, buffer, 1) != 1) {
+ daemonized.write_to_stderr = errno;
+ if (daemonized.write_to_stderr == 0)
+ daemonized.write_to_stderr = -1;
+ } else
+ daemonized.write_to_stderr = 0;
+
+ /* Make sure parent exits. */
+ while (getppid() == pid)
+ sleep(1);
+ daemonized.ppid = getppid();
+ if (write(fds[1], &daemonized, sizeof(daemonized))
+ != sizeof(daemonized))
+ exit(1);
+ exit(0);
+ }
+
+ if (read(fds[0], &daemonized, sizeof(daemonized)) != sizeof(daemonized))
+ err(1, "Failed read");
+
+ ok1(daemonized.pid != pid);
+ ok1(daemonized.ppid == 1);
+ ok1(daemonized.in_root_dir);
+ ok1(daemonized.read_from_stdin == 0);
+ ok1(daemonized.write_to_stdout == 0);
+ ok1(daemonized.write_to_stderr == 0);
+
+ return exit_status();
+}
--- /dev/null
+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. Neither the name of the University nor the names of its contributors
+ may be used to endorse or promote products derived from this software
+ without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.