Replace homegrown PID file functions with std BSD pidfile()

- Import pidfile() v1.11 from OpenBSD and libite (-lite) project
- Import utimensat() replacement, for systems that don't have it
- Simplify syslogd and klogd program start and PID file creation
- Rip out -i and -I from klogd, uses old PID file functions, and
  they're only kill(1) wrappers anyway

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

configure.ac

@@ -40,7 +40,7 @@ AC_HEADER_STDC
 PKG_PROG_PKG_CONFIG
 
 # Check for usually missing API's, which we can replace
-AC_REPLACE_FUNCS([strlcpy strlcat])
+AC_REPLACE_FUNCS([pidfile strlcpy strlcat utimensat])
 AC_CONFIG_LIBOBJ_DIR([lib])
 
 # Command line options

lib/pidfile.c

@@ -0,0 +1,138 @@
+/*	Updated by troglobit for libite/finit/uftpd projects 2016/07/04 */
+/*	$OpenBSD: pidfile.c,v 1.11 2015/06/03 02:24:36 millert Exp $	*/
+/*	$NetBSD: pidfile.c,v 1.4 2001/02/19 22:43:42 cgd Exp $	*/
+
+/*-
+ * Copyright (c) 1999 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Jason R. Thorpe.
+ *
+ * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
+ */
+
+#define _GNU_SOURCE		/* Needed with GLIBC to get asprintf() */
+#include <sys/stat.h>		/* utimensat() */
+#include <sys/time.h>		/* utimensat() on *BSD */
+#include <sys/types.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include "compat.h"
+
+#ifndef HAVE_UTIMENSAT
+int utimensat(int dirfd, const char *pathname, const struct timespec ts[2], int flags);
+#endif
+
+static char *pidfile_path = NULL;
+static pid_t pidfile_pid  = 0;
+
+static void pidfile_cleanup(void);
+
+const  char *__pidfile_path = LOCALSTATEDIR "/run";
+const  char *__pidfile_name = NULL;
+
+int
+pidfile(const char *basename)
+{
+	int save_errno;
+	int atexit_already;
+	pid_t pid;
+	FILE *f;
+
+	if (basename == NULL)
+		basename = getprogname();
+
+	pid = getpid();
+	atexit_already = 0;
+
+	if (pidfile_path != NULL) {
+		if (!access(pidfile_path, R_OK) && pid == pidfile_pid) {
+			utimensat(0, pidfile_path, NULL, 0);
+			return (0);
+		}
+		free(pidfile_path);
+		pidfile_path = NULL;
+		__pidfile_name = NULL;
+		atexit_already = 1;
+	}
+
+	if (basename[0] != '/') {
+		if (asprintf(&pidfile_path, "%s/%s.pid", __pidfile_path, basename) == -1)
+			return (-1);
+	} else {
+		if (asprintf(&pidfile_path, "%s", basename) == -1)
+			return (-1);
+	}
+
+	if ((f = fopen(pidfile_path, "w")) == NULL) {
+		save_errno = errno;
+		free(pidfile_path);
+		pidfile_path = NULL;
+		errno = save_errno;
+		return (-1);
+	}
+
+	if (fprintf(f, "%ld\n", (long)pid) <= 0 || fflush(f) != 0) {
+		save_errno = errno;
+		(void) fclose(f);
+		(void) unlink(pidfile_path);
+		free(pidfile_path);
+		pidfile_path = NULL;
+		errno = save_errno;
+		return (-1);
+	}
+	(void) fclose(f);
+	__pidfile_name = pidfile_path;
+
+	/*
+	 * LITE extension, no need to set up another atexit() handler
+	 * if user only called us to update the mtime of the PID file
+	 */
+	if (atexit_already)
+		return (0);
+
+	pidfile_pid = pid;
+	if (atexit(pidfile_cleanup) < 0) {
+		save_errno = errno;
+		(void) unlink(pidfile_path);
+		free(pidfile_path);
+		pidfile_path = NULL;
+		pidfile_pid = 0;
+		errno = save_errno;
+		return (-1);
+	}
+
+	return (0);
+}
+
+static void
+pidfile_cleanup(void)
+{
+	if (pidfile_path != NULL && pidfile_pid == getpid()) {
+		(void) unlink(pidfile_path);
+		free(pidfile_path);
+		pidfile_path = NULL;
+	}
+}

lib/utimensat.c

@@ -0,0 +1,47 @@
+/* Replacement in case utimensat(2) is missing
+ *
+ * Copyright (C) 2017-2018  Joachim Nilsson <troglobit@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "config.h"
+
+#include <errno.h>
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#include <sys/time.h>		/* lutimes(), utimes(), utimensat() */
+
+int utimensat(int dirfd, const char *pathname, const struct timespec ts[2], int flags)
+{
+	int ret = -1;
+	struct timeval tv[2];
+
+	if (dirfd != 0) {
+		errno = ENOTSUP;
+		return -1;
+	}
+
+	TIMESPEC_TO_TIMEVAL(&tv[0], &ts[0]);
+	TIMESPEC_TO_TIMEVAL(&tv[1], &ts[1]);
+
+#ifdef AT_SYMLINK_NOFOLLOW
+	if ((flags & AT_SYMLINK_NOFOLLOW) == AT_SYMLINK_NOFOLLOW)
+		ret = lutimes(pathname, tv);
+	else
+#endif
+		ret = utimes(pathname, tv);
+
+	return ret;
+}

man/klogd.8

@@ -31,14 +31,6 @@ Enable debugging mode.  This will generate potentially LOTS of output to
 stderr.
 .It Fl f Ar FILE
 Log messages to the specified filename rather than to the syslog facility.
-.It Fl i | Fl I
-Signal the currently executing klogd daemon.  Both of these switches control
-the loading/reloading of symbol information.  The
-.Fl i
-switch signals the daemon to reload the kernel module symbols.  The
-.Fl I
-switch signals for a reload of both the static kernel symbols and the
-kernel module symbols.
 .It Fl n
 Avoid auto-backgrounding.  This is needed especially if
 .Nm
@@ -251,22 +243,23 @@ Proper and accurate resolution of addresses in kernel modules requires
 that
 .Nm
 be informed whenever the kernel module status changes.  The
-.Fl i
+.Ar SIGUSR1
 and
-.Fl I
+.Ar SIGUSR2
-switches can be used to signal the currently executing daemon that
+signals can be used to signal the currently executing
-symbol information be reloaded.  Of most importance to proper resolution
+.Nm
-of module symbols is the
+that symbol information should be reloaded.  Of most importance to
-.Fl i
+proper resolution of module symbols is
-switch.  Each time a kernel module is loaded or removed from the kernel
+.Ar SIGUSR1 .
-the following command should be executed:
+Each time a kernel module is loaded or removed from the kernel the
+following command should be executed:
 .Bd -literal -offset indent
-klogd -i
+kill -USR1 `cat /run/klogd.pid`
 .Ed
 .Pp
 The
 .Fl p
-switch can also be used to insure that module symbol information is up
+switch can also be used to ensure that module symbol information is up
 to date.  This switch instructs
 .Nm
 to reload the module symbol information whenever a protection fault

src/Makefile.am

@@ -23,19 +23,20 @@ lib_LTLIBRARIES  = libsyslog.la
 
 AM_CFLAGS        = -W -Wall -Wextra
 AM_CFLAGS       += -Wno-unused-result -Wno-unused-parameter -fno-strict-aliasing
+AM_CPPFLAGS      = -DSYSCONFDIR=\"@sysconfdir@\" -DLOCALSTATEDIR=\"@localstatedir@\"
+AM_CPPFLAGS     += -D_BSD_SOURCE -D_DEFAULT_SOURCE
 
-syslogd_SOURCES  = syslogd.c syslog.h pidfile.c pidfile.h queue.h
+syslogd_SOURCES  = syslogd.c syslog.h queue.h
-syslogd_CPPFLAGS = -D_XOPEN_SOURCE=600 -D_BSD_SOURCE -D_DEFAULT_SOURCE
+syslogd_CPPFLAGS = $(AM_CPPFLAGS) -D_XOPEN_SOURCE=600
 syslogd_LDADD    = $(LIBS) $(LIBOBJS)
 
-klogd_SOURCES    = klogd.c klogd.h syslog.h pidfile.c pidfile.h \
+klogd_SOURCES    = klogd.c klogd.h syslog.h ksym.c ksyms.h ksym_mod.c module.h
-		   ksym.c ksyms.h ksym_mod.c module.h
+klogd_CPPFLAGS   = $(AM_CPPFLAGS) -DALLOW_KERNEL_LOGGING
-klogd_CPPFLAGS   = -DALLOW_KERNEL_LOGGING -D_BSD_SOURCE -D_DEFAULT_SOURCE
 klogd_LDADD      = $(LIBS) $(LIBOBJS)
 klogd_LDADD     += libsyslog.la
 
 logger_SOURCES   = logger.c syslog.h
-logger_CPPFLAGS  = -D_XOPEN_SOURCE=600 -D_BSD_SOURCE -D_DEFAULT_SOURCE
+logger_CPPFLAGS  = $(AM_CPPFLAGS) -D_XOPEN_SOURCE=600
 logger_LDADD     = $(LIBS) $(LIBOBJS)
 logger_LDADD    += libsyslog.la
 
@@ -44,5 +45,5 @@ pkgincludedir         = $(includedir)/syslog
 pkgconfig_DATA        = libsyslog.pc
 pkginclude_HEADERS    = syslog.h
 libsyslog_la_SOURCES  = syslog.c syslog.h
-libsyslog_la_CPPFLAGS = -D_XOPEN_SOURCE=600 -D_BSD_SOURCE -D_DEFAULT_SOURCE
+libsyslog_la_CPPFLAGS = $(AM_CPPFLAGS) -D_XOPEN_SOURCE=600
 libsyslog_la_LDFLAGS  = $(AM_LDFLAGS) -version-info 0:0:0

src/compat.h

@@ -65,6 +65,10 @@ size_t strlcpy(char *dst, const char *src, size_t siz);
 size_t strlcat(char *dst, const char *src, size_t siz);
 #endif
 
+#ifndef pidfile
+int pidfile(const char *basename);
+#endif
+
 static inline char *getprogname(void)
 {
 	extern char *__progname;

src/klogd.c

@@ -23,6 +23,7 @@
  */
 
 #include "config.h"
+#include "compat.h"
 
 #include <errno.h>
 #include <getopt.h>
@@ -35,9 +36,6 @@
 #include <stdarg.h>
 #include <stdlib.h>
 #include <sys/stat.h>
-#ifndef TESTING
-#include "pidfile.h"
-#endif
 
 #define __LIBRARY__
 #include <linux/unistd.h>
@@ -47,9 +45,7 @@
 #define LOG_BUFFER_SIZE 4096
 #define LOG_LINE_LENGTH 1000
 
-#ifndef TESTING
 static char *PidFile = _PATH_VARRUN "klogd.pid";
-#endif
 
 static int kmsg;
 static int change_state      = 0;
@@ -81,7 +77,6 @@ extern void        stop_logging(int sig);
 extern void        stop_daemon(int sig);
 extern void        reload_daemon(int sig);
 static void        Terminate(void);
-static void        SignalDaemon(int);
 static void        ReloadSymbols(void);
 static void        ChangeLogging(void);
 static enum LOGSRC GetKernelLogSrc(void);
@@ -115,12 +110,10 @@ static void CloseLogSrc(void)
 /*
  * Signal handler to terminate the parent process.
  */
-#ifndef TESTING
 void doexit(int signo)
 {
 	exit(0);
 }
-#endif
 
 void restart(int signo)
 {
@@ -153,26 +146,14 @@ static void Terminate(void)
 	CloseLogSrc();
 	Syslog(LOG_INFO, "Kernel log daemon terminating.");
 	sleep(1);
+
 	if (output_file != NULL)
 		fclose(output_file);
 	closelog();
-#ifndef TESTING
+
-	(void)remove_pid(PidFile);
-#endif
 	exit(1);
 }
 
-static void SignalDaemon(int signo)
-{
-#ifndef TESTING
-	int pid = check_pid(PidFile);
-
-	kill(pid, signo);
-#else
-	kill(getpid(), signo);
-#endif
-}
-
 static void ReloadSymbols(void)
 {
 	if (symbol_lookup) {
@@ -257,7 +238,6 @@ static enum LOGSRC GetKernelLogSrc(void)
 		return kernel;
 	}
 
-#ifndef TESTING
 	if ((kmsg = open(_PATH_KLOG, O_RDONLY)) < 0) {
 		fprintf(stderr, "klogd: Cannot open proc file system, "
 		                "%d - %s.\n",
@@ -265,12 +245,10 @@ static enum LOGSRC GetKernelLogSrc(void)
 		ksyslog(7, NULL, 0);
 		exit(1);
 	}
-#else
-	kmsg = fileno(stdin);
-#endif
 
 	Syslog(LOG_INFO, "klogd v%s, log source = %s started.",
 	       VERSION, _PATH_KLOG);
+
 	return proc;
 }
 
@@ -333,18 +311,12 @@ extern void Syslog(int priority, char *fmt, ...)
 		}
 		syslog(priority, fmt, argl);
 		va_end(ap);
-#ifdef TESTING
-		putchar('\n');
-#endif
 		return;
 	}
 
 	va_start(ap, fmt);
 	vsyslog(priority, fmt, ap);
 	va_end(ap);
-#ifdef TESTING
-	printf("\n");
-#endif
 }
 
 /*
@@ -648,6 +620,8 @@ int usage(int code)
 	        "  -v        Show program version and exit\n"
 	        "  -x        Omit EIP translation, i.e. do not read System.map file\n"
 	        "\n"
+		"SIGUSR1 reloads kernel module symbols, SIGUSR2 reloads all kernel symbols.\n"
+	        "\n"
 	        "Bug report address: %s\n",
 	        PACKAGE_BUGREPORT);
 	exit(code);
@@ -659,14 +633,10 @@ int main(int argc, char *argv[])
 	char *output = NULL;
 	int use_output = 0;
 	int ch;
-#ifndef TESTING
 	pid_t ppid = getpid();
 
-	chdir("/");
-#endif
-
 	/* Parse the command-line. */
-	while ((ch = getopt(argc, argv, "c:df:iIk:nopsvx2?")) != EOF) {
+	while ((ch = getopt(argc, argv, "c:df:k:nopsvx2?")) != EOF) {
 		switch (ch) {
 		case '2': /* Print lines with symbols twice. */
 			symbols_twice = 1;
@@ -685,14 +655,6 @@ int main(int argc, char *argv[])
 			use_output++;
 			break;
 
-		case 'i': /* Reload module symbols. */
-			SignalDaemon(SIGUSR1);
-			return 0;
-
-		case 'I':
-			SignalDaemon(SIGUSR2);
-			return 0;
-
 		case 'k': /* Kernel symbol file. */
 			symfile = optarg;
 			break;
@@ -743,7 +705,6 @@ int main(int argc, char *argv[])
 		console_log_level = *log_level - '0';
 	}
 
-#ifndef TESTING
 	/*
 	 * The following code allows klogd to auto-background itself.
 	 * What happens is that the program forks and the parent quits.
@@ -756,48 +717,40 @@ int main(int argc, char *argv[])
 	 * such process running.
 	 */
 	if ((!one_shot) && (!no_fork)) {
-		if (!check_pid(PidFile)) {
+		signal(SIGTERM, doexit);
-			signal(SIGTERM, doexit);
+		if (fork() == 0) {
-			if (fork() == 0) {
+			int num_fds = getdtablesize();
-				int num_fds = getdtablesize();
+			int fl;
-				int fl;
 
-				signal(SIGTERM, SIG_DFL);
+			signal(SIGTERM, SIG_DFL);
 
-				/* This is the child closing its file descriptors. */
+			/* This is the child closing its file descriptors. */
-				for (fl = 0; fl <= num_fds; ++fl) {
+			for (fl = 0; fl <= num_fds; ++fl) {
-					if (fileno(stdout) == fl && use_output)
+				if (fileno(stdout) == fl && use_output)
-						if (strcmp(output, "-") == 0)
+					if (strcmp(output, "-") == 0)
-							continue;
+						continue;
-					close(fl);
+				close(fl);
-				}
-
-				setsid();
-			} else {
-				/*
-				 * Parent process
-				 */
-				sleep(300);
-				/*
-				 * Not reached unless something major went wrong.
-				 */
-				exit(1);
 			}
+
+			chdir("/");
+			setsid();
 		} else {
-			fputs("klogd: Already running.\n", stderr);
+			/*
+			 * Parent process
+			 */
+			sleep(300);
+			/*
+			 * Not reached unless something major went wrong.
+			 */
 			exit(1);
-		}
+			}
 	}
 
-	/* tuck my process id away */
+	if (pidfile(PidFile)) {
-	if (!check_pid(PidFile)) {
+		Syslog(LOG_ERR, "Failed creating PID file %s: %s",
-		if (!write_pid(PidFile))
+		       PidFile, strerror(errno));
-			Terminate();
-	} else {
-		fputs("klogd: Already running.\n", stderr);
 		Terminate();
 	}
-#endif
 
 	/* Signal setups. */
 	for (ch = 1; ch < NSIG; ++ch)

src/pidfile.c

@@ -1,147 +0,0 @@
-/*-
- * SPDX-License-Identifier: GPL-2.0-or-later
- *
- * pidfile.c - interact with pidfiles
- * Copyright (c) 1995  Martin Schulze <Martin.Schulze@Linux.DE>
- *
- * This file is part of the sysklogd package, a kernel and system log daemon.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this file; see the file COPYING.  If not, write to the
- * Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
- * MA 02110-1301, USA.
- */
-
-#include <errno.h>
-#include <fcntl.h>
-#include <signal.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/file.h>
-#include <sys/stat.h>
-#include <unistd.h>
-
-/* read_pid
- *
- * Reads the specified pidfile and returns the read pid.
- * 0 is returned if either there's no pidfile, it's empty
- * or no pid can be read.
- */
-int read_pid(char *pidfile)
-{
-	FILE *fp;
-	int pid;
-
-	fp = fopen(pidfile, "r");
-	if (!fp)
-		return 0;
-
-	fscanf(fp, "%d", &pid);
-	fclose(fp);
-
-	return pid;
-}
-
-/* check_pid
- *
- * Reads the pid using read_pid and looks up the pid in the process
- * table (using /proc) to determine if the process already exists. If
- * so 1 is returned, otherwise 0.
- */
-int check_pid(char *pidfile)
-{
-	int pid = read_pid(pidfile);
-
-	/* Amazing ! _I_ am already holding the pid file... */
-	if ((!pid) || (pid == getpid()))
-		return 0;
-
-	/*
-	 * The 'standard' method of doing this is to try and do a 'fake' kill
-	 * of the process.  If an ESRCH error is returned the process cannot
-	 * be found -- GW
-	 */
-	/* But... errno is usually changed only on error.. */
-	if (kill(pid, 0) && errno == ESRCH)
-		return 0;
-
-	return pid;
-}
-
-/* write_pid
- *
- * Writes the pid to the specified file. If that fails 0 is
- * returned, otherwise the pid.
- */
-int write_pid(char *pidfile)
-{
-	FILE *fp;
-	int   fd;
-	int   pid;
-
-	if (((fd = open(pidfile, O_RDWR | O_CREAT | O_TRUNC, 0644)) == -1) || ((fp = fdopen(fd, "r+")) == NULL)) {
-		fprintf(stderr, "Can't open or create %s.\n", pidfile);
-		return 0;
-	}
-
-	if (flock(fd, LOCK_EX | LOCK_NB) == -1) {
-		fscanf(fp, "%d", &pid);
-		fclose(fp);
-		printf("Can't lock, lock is held by pid %d.\n", pid);
-		return 0;
-	}
-
-	pid = getpid();
-	if (!fprintf(fp, "%d\n", pid)) {
-		printf("Can't write pid , %s.\n", strerror(errno));
-		close(fd);
-		return 0;
-	}
-	fflush(fp);
-
-	if (flock(fd, LOCK_UN) == -1) {
-		printf("Can't unlock pidfile %s, %s.\n", pidfile, strerror(errno));
-		close(fd);
-		return 0;
-	}
-	close(fd);
-
-	return pid;
-}
-
-/* touch_pid
- *
- * Touches the specified pidfile f.ex. when receiving a SIGHUP
- * The result from utimensat() is returned
- */
-int touch_pid(char *pidfile)
-{
-	return utimensat(0, pidfile, NULL, 0);
-}
-
-/* remove_pid
- *
- * Remove the the specified file. The result from unlink(2)
- * is returned
- */
-int remove_pid(char *pidfile)
-{
-	return unlink(pidfile);
-}
-
-/**
- * Local Variables:
- *  indent-tabs-mode: t
- *  c-file-style: "linux"
- * End:
- */

src/pidfile.h

@@ -1,65 +0,0 @@
-/*-
- * SPDX-License-Identifier: GPL-2.0-or-later
- *
- * pidfile.h - interact with pidfiles
- * Copyright (c) 1995  Martin Schulze <Martin.Schulze@Linux.DE>
- *
- * This file is part of the sysklogd package, a kernel and system log daemon.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this file; see the file COPYING.  If not, write to the
- * Free Software Foundation, 51 Franklin Street - Fifth Floor, Boston,
- * MA 02110-1301, USA.
- */
-
-#ifndef SYSKLOGD_PIDFILE_H_
-#define SYSKLOGD_PIDFILE_H_
-
-/* read_pid
- *
- * Reads the specified pidfile and returns the read pid.
- * 0 is returned if either there's no pidfile, it's empty
- * or no pid can be read.
- */
-int read_pid (char *pidfile);
-
-/* check_pid
- *
- * Reads the pid using read_pid and looks up the pid in the process
- * table (using /proc) to determine if the process already exists. If
- * so 1 is returned, otherwise 0.
- */
-int check_pid (char *pidfile);
-
-/* write_pid
- *
- * Writes the pid to the specified file. If that fails 0 is
- * returned, otherwise the pid.
- */
-int write_pid (char *pidfile);
-
-/* touch_pid
- *
- * Touches the specified pidfile f.ex. when receiving a SIGHUP
- * The result from utimensat() is returned
- */
-int touch_pid (char *pidfile);
-
-/* remove_pid
- *
- * Remove the the specified file. The result from unlink(2)
- * is returned
- */
-int remove_pid (char *pidfile);
-
-#endif /* SYSKLOGD_PIDFILE_H_ */

src/syslogd.c

@@ -96,7 +96,6 @@ static char sccsid[] __attribute__((unused)) =
 #include <syscall.h>
 #include <paths.h>
 
-#include "pidfile.h"
 #include "syslogd.h"
 #include "compat.h"
 
@@ -448,52 +447,39 @@ int main(int argc, char *argv[])
 		usage(1);
 
 	if ((!Foreground) && (!Debug)) {
-		logit("Checking pidfile.\n");
+		signal(SIGTERM, doexit);
-		if (!check_pid(PidFile)) {
+		chdir("/");
-			signal(SIGTERM, doexit);
-			chdir("/");
 
-			if (fork()) {
+		if (fork()) {
-				/*
+			/*
-				 * Parent process
+			 * Parent process
-				 */
+			 */
-				sleep(300);
+			sleep(300);
-				/*
+			/*
-				 * Not reached unless something major went wrong.  5
+			 * Not reached unless something major went wrong.  5
-				 * minutes should be a fair amount of time to wait.
+			 * minutes should be a fair amount of time to wait.
-				 * Please note that this procedure is important since
+			 * Please note that this procedure is important since
-				 * the father must not exit before syslogd isn't
+			 * the father must not exit before syslogd isn't
-				 * initialized or the klogd won't be able to flush its
+			 * initialized or the klogd won't be able to flush its
-				 * logs.  -Joey
+			 * logs.  -Joey
-				 */
+			 */
-				exit(1);
-			}
-			signal(SIGTERM, SIG_DFL);
-			num_fds = getdtablesize();
-			for (i = 0; i < num_fds; i++)
-				(void)close(i);
-			untty();
-		} else {
-			fputs("syslogd: Already running.\n", stderr);
 			exit(1);
 		}
+
+		signal(SIGTERM, SIG_DFL);
+		num_fds = getdtablesize();
+		for (i = 0; i < num_fds; i++)
+			(void)close(i);
+		untty();
 	} else {
 		debugging_on = 1;
 		setlinebuf(stdout);
 	}
 
-	/* tuck my process id away */
 	if (!Debug) {
-		logit("Writing pidfile.\n");
+		if (pidfile(PidFile)) {
-		if (!check_pid(PidFile)) {
+			logit("Failed creating PID file %s: %s",
-			if (!write_pid(PidFile)) {
+			      PidFile, strerror(errno));
-				logit("Can't write pid.\n");
-				if (getpid() != ppid)
-					kill(ppid, SIGTERM);
-				exit(1);
-			}
-		} else {
-			logit("Pidfile (and pid) already exist.\n");
 			if (getpid() != ppid)
 				kill(ppid, SIGTERM);
 			exit(1);
@@ -593,13 +579,8 @@ int main(int argc, char *argv[])
 			logit("\nReceived SIGHUP, reloading syslogd.\n");
 			init();
 
-			if (check_pid(PidFile)) {
+			if (pidfile(PidFile))
-				if (touch_pid(PidFile))
+				flog(LOG_SYSLOG | LOG_ERR, "Failed writing %s", PidFile);
-					logerror("Not possible to touch pidfile");
-			} else {
-				if (!write_pid(PidFile))
-					logerror("Failed to write pidfile");
-			}
 			continue;
 		}
 
@@ -2267,7 +2248,6 @@ void die(int signo)
 	if (parts)
 		free(parts);
 
-	(void)remove_pid(PidFile);
 	exit(0);
 }