diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/util/pidfile.c | 131 | ||||
| -rw-r--r-- | lib/util/pidfile.h | 26 | ||||
| -rwxr-xr-x | lib/util/wscript_build | 2 |
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', |