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-rw-r--r--lib/util/pidfile.c131
-rw-r--r--lib/util/pidfile.h26
-rwxr-xr-xlib/util/wscript_build2
3 files changed, 158 insertions, 1 deletions
diff --git a/lib/util/pidfile.c b/lib/util/pidfile.c
new file mode 100644
index 0000000000..ac8ff8a0c3
--- /dev/null
+++ b/lib/util/pidfile.c
@@ -0,0 +1,131 @@
+/* this code is broken - there is a race condition with the unlink (tridge) */
+
+/*
+ Unix SMB/CIFS implementation.
+ pidfile handling
+ Copyright (C) Andrew Tridgell 1998
+
+ 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 3 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 program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "system/filesys.h"
+#include "lib/util/pidfile.h"
+
+/**
+ * @file
+ * @brief Pid file handling
+ */
+
+/**
+ * return the pid in a pidfile. return 0 if the process (or pidfile)
+ * does not exist
+ */
+pid_t pidfile_pid(const char *piddir, const char *name)
+{
+ int fd;
+ char pidstr[20];
+ pid_t ret;
+ char *pidFile;
+
+ if (asprintf(&pidFile, "%s/%s.pid", piddir, name) < 0) {
+ return 0;
+ }
+
+ fd = open(pidFile, O_NONBLOCK | O_RDONLY, 0644);
+
+ if (fd == -1) {
+ SAFE_FREE(pidFile);
+ return 0;
+ }
+
+ ZERO_STRUCT(pidstr);
+
+ if (read(fd, pidstr, sizeof(pidstr)-1) <= 0) {
+ goto noproc;
+ }
+
+ ret = (pid_t)atoi(pidstr);
+ if (ret <= 0) {
+ goto noproc;
+ }
+
+ if (!process_exists_by_pid(ret)) {
+ goto noproc;
+ }
+
+ if (fcntl_lock(fd,F_SETLK,0,1,F_RDLCK)) {
+ /* we could get the lock - it can't be a Samba process */
+ goto noproc;
+ }
+
+ close(fd);
+ SAFE_FREE(pidFile);
+ return ret;
+
+ noproc:
+ close(fd);
+ unlink(pidFile);
+ SAFE_FREE(pidFile);
+ return 0;
+}
+
+/**
+ * create a pid file in the pid directory. open it and leave it locked
+ */
+void pidfile_create(const char *piddir, const char *name)
+{
+ int fd;
+ char buf[20];
+ char *pidFile;
+ pid_t pid;
+
+ if (asprintf(&pidFile, "%s/%s.pid", piddir, name) < 0) {
+ DEBUG(0,("ERROR: Out of memory\n"));
+ exit(1);
+ }
+
+ pid = pidfile_pid(piddir, name);
+ if (pid != 0) {
+ DEBUG(0,("ERROR: %s is already running. File %s exists and process id %d is running.\n",
+ name, pidFile, (int)pid));
+ exit(1);
+ }
+
+ fd = open(pidFile, O_NONBLOCK | O_CREAT | O_WRONLY | O_EXCL, 0644);
+ if (fd == -1) {
+ DEBUG(0,("ERROR: can't open %s: Error was %s\n", pidFile,
+ strerror(errno)));
+ exit(1);
+ }
+
+ smb_set_close_on_exec(fd);
+
+ if (fcntl_lock(fd,F_SETLK,0,1,F_WRLCK)==false) {
+ DEBUG(0,("ERROR: %s : fcntl lock of file %s failed. Error was %s\n",
+ name, pidFile, strerror(errno)));
+ exit(1);
+ }
+
+ memset(buf, 0, sizeof(buf));
+ slprintf(buf, sizeof(buf) - 1, "%u\n", (unsigned int) getpid());
+ if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) {
+ DEBUG(0,("ERROR: can't write to file %s: %s\n",
+ pidFile, strerror(errno)));
+ exit(1);
+ }
+
+ /* Leave pid file open & locked for the duration... */
+ SAFE_FREE(pidFile);
+}
diff --git a/lib/util/pidfile.h b/lib/util/pidfile.h
new file mode 100644
index 0000000000..92a277d820
--- /dev/null
+++ b/lib/util/pidfile.h
@@ -0,0 +1,26 @@
+/*
+ Unix SMB/CIFS implementation.
+ Samba utility functions
+ Copyright (C) Jeremy Allison 2012.
+
+ 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 3 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 program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef _SAMBA_PIDFILE_H_
+#define _SAMBA_PIDFILE_H_
+
+pid_t pidfile_pid(const char *piddir, const char *name);
+void pidfile_create(const char *piddir, const char *program_name);
+
+#endif
diff --git a/lib/util/wscript_build b/lib/util/wscript_build
index 340cf12cd4..ddaf90ffc2 100755
--- a/lib/util/wscript_build
+++ b/lib/util/wscript_build
@@ -7,7 +7,7 @@ bld.SAMBA_LIBRARY('samba-util',
signal.c system.c params.c util.c util_id.c util_net.c
util_strlist.c util_paths.c idtree.c debug.c fault.c base64.c
util_str.c util_str_common.c substitute.c ms_fnmatch.c
- server_id.c dprintf.c parmlist.c bitmap.c''',
+ server_id.c dprintf.c parmlist.c bitmap.c pidfile.c''',
deps='DYNCONFIG',
public_deps='talloc execinfo uid_wrapper pthread LIBCRYPTO charset util_setid',
public_headers='debug.h attr.h byteorder.h data_blob.h memory.h safe_string.h time.h talloc_stack.h xfile.h dlinklist.h samba_util.h string_wrappers.h',