--- /dev/null
+/*
+ * Copyright (c) 1995-2008, Index Data
+ * All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * 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.
+ * * Neither the name of Index Data 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 AND 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.
+ */
+/* $Id: daemon.h,v 1.1 2008-02-18 17:07:05 adam Exp $ */
+
+/**
+ * \file daemon.h
+ * \brief Unix daemon management
+ */
+
+#ifndef YAZ_DAEMON_H
+#define YAZ_DAEMON_H
+
+#include <stdio.h>
+#include <yaz/yconfig.h>
+
+YAZ_BEGIN_CDECL
+
+#define YAZ_DAEMON_FORK 1
+#define YAZ_DAEMON_DEBUG 2
+#define YAZ_DAEMON_KEEPALIVE 4
+
+int yaz_daemon(const char *progname,
+ unsigned int flags,
+ void (*work)(void *data), void *data,
+ const char *pidfile, const char *uid);
+
+YAZ_END_CDECL
+
+#endif
+/*
+ * Local variables:
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ * vim: shiftwidth=4 tabstop=8 expandtab
+ */
+
--- /dev/null
+/*
+ * Copyright (C) 1995-2008, Index Data ApS
+ * See the file LICENSE for details.
+ *
+ * $Id: daemon.c,v 1.1 2008-02-18 17:07:06 adam Exp $
+ */
+
+/**
+ * \file
+ * \brief Unix daemon management
+ */
+
+#if HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <signal.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <pwd.h>
+
+#include <yaz/daemon.h>
+#include <yaz/log.h>
+#include <yaz/snprintf.h>
+
+static void write_pidfile(int pid_fd)
+{
+ if (pid_fd != -1)
+ {
+ char buf[40];
+ yaz_snprintf(buf, sizeof(buf), "%ld", (long) getpid());
+ if (ftruncate(pid_fd, 0))
+ {
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "ftruncate");
+ exit(1);
+ }
+ if (write(pid_fd, buf, strlen(buf)) != strlen(buf))
+ {
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "write");
+ exit(1);
+ }
+ close(pid_fd);
+ }
+}
+
+pid_t child_pid = 0;
+static void kill_child_handler(int num)
+{
+ if (child_pid)
+ kill(child_pid, num);
+}
+
+static void keepalive(void (*work)(void *data), void *data)
+{
+ int run = 1;
+ int cont = 1;
+ void (*old_sighup)(int);
+ void (*old_sigterm)(int);
+
+ /* keep signals in their original state and make sure that some signals
+ to parent process also gets sent to the child..
+ */
+ old_sighup = signal(SIGHUP, kill_child_handler);
+ old_sigterm = signal(SIGTERM, kill_child_handler);
+ while (cont)
+ {
+ pid_t p = fork();
+ pid_t p1;
+ int status;
+ if (p == (pid_t) (-1))
+ {
+
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "fork");
+ exit(1);
+ }
+ else if (p == 0)
+ {
+ /* child */
+ signal(SIGHUP, old_sighup); /* restore */
+ signal(SIGTERM, old_sigterm);/* restore */
+
+ work(data);
+ exit(0);
+ }
+
+ /* enable signalling in kill_child_handler */
+ child_pid = p;
+
+ p1 = wait(&status);
+
+ /* disable signalling in kill_child_handler */
+ child_pid = 0;
+
+ if (p1 != p)
+ {
+ yaz_log(YLOG_FATAL, "p1=%d != p=%d", p1, p);
+ exit(1);
+ }
+
+ if (WIFSIGNALED(status))
+ {
+ /* keep the child alive in case of errors, but _log_ */
+ switch(WTERMSIG(status)) {
+ case SIGILL:
+ yaz_log(YLOG_WARN, "Received SIGILL from child %ld", (long) p);
+ cont = 1;
+ break;
+ case SIGABRT:
+ yaz_log(YLOG_WARN, "Received SIGABRT from child %ld", (long) p);
+ cont = 1;
+ break ;
+ case SIGSEGV:
+ yaz_log(YLOG_WARN, "Received SIGSEGV from child %ld", (long) p);
+ cont = 1;
+ break;
+ case SIGBUS:
+ yaz_log(YLOG_WARN, "Received SIGBUS from child %ld", (long) p);
+ cont = 1;
+ break;
+ case SIGTERM:
+ yaz_log(YLOG_LOG, "Received SIGTERM from child %ld",
+ (long) p);
+ cont = 0;
+ break;
+ default:
+ yaz_log(YLOG_WARN, "Received SIG %d from child %ld",
+ WTERMSIG(status), (long) p);
+ cont = 0;
+ }
+ }
+ else if (status == 0)
+ cont = 0; /* child exited normally */
+ else
+ { /* child exited with error */
+ yaz_log(YLOG_LOG, "Exit %d from child %ld", status, (long) p);
+ cont = 0;
+ }
+ if (cont) /* respawn slower as we get more errors */
+ sleep(1 + run/5);
+ run++;
+ }
+}
+
+int yaz_daemon(const char *progname,
+ unsigned int flags,
+ void (*work)(void *data), void *data,
+ const char *pidfile, const char *uid)
+{
+ int pid_fd = -1;
+
+ /* open pidfile .. defer write until in child and after setuid */
+ if (pidfile)
+ {
+ pid_fd = open(pidfile, O_CREAT|O_RDWR, 0666);
+ if (pid_fd == -1)
+ {
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "open %s", pidfile);
+ exit(1);
+ }
+ }
+
+ if (flags & YAZ_DAEMON_DEBUG)
+ {
+ /* in debug mode.. it's quite simple */
+ write_pidfile(pid_fd);
+ work(data);
+ exit(0);
+ }
+
+ /* running in production mode. */
+ if (uid)
+ {
+ /* OK to use the non-thread version here */
+ struct passwd *pw = getpwnam(uid);
+ if (!pw)
+ {
+ yaz_log(YLOG_FATAL, "%s: Unknown user", uid);
+ exit(1);
+ }
+ if (setuid(pw->pw_uid) < 0)
+ {
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "setuid");
+ exit(1);
+ }
+ }
+
+ if (flags & YAZ_DAEMON_FORK)
+ {
+ /* create pipe so that parent waits until child has created
+ PID (or failed) */
+ static int hand[2]; /* hand shake for child */
+ if (pipe(hand) < 0)
+ {
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "pipe");
+ return 1;
+ }
+ switch (fork())
+ {
+ case 0:
+ break;
+ case -1:
+ return 1;
+ default:
+ close(hand[1]);
+ while(1)
+ {
+ char dummy[1];
+ int res = read(hand[0], dummy, 1);
+ if (res < 0 && errno != EINTR)
+ {
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "read fork handshake");
+ break;
+ }
+ else if (res >= 0)
+ break;
+ }
+ close(hand[0]);
+ _exit(0);
+ }
+ /* child */
+ close(hand[0]);
+ if (setsid() < 0)
+ return 1;
+
+ close(0);
+ close(1);
+ close(2);
+ open("/dev/null", O_RDWR);
+ dup(0); dup(0);
+ close(hand[1]);
+ }
+
+ write_pidfile(pid_fd);
+
+ if (flags & YAZ_DAEMON_KEEPALIVE)
+ {
+ keepalive(work, data);
+ }
+ else
+ {
+ work(data);
+ }
+ return 0;
+}
+
+/*
+ * Local variables:
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ * vim: shiftwidth=4 tabstop=8 expandtab
+ */