diff options
author | Jelmer Vernooij <jelmer@samba.org> | 2006-02-23 15:52:24 +0000 |
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committer | Gerald (Jerry) Carter <jerry@samba.org> | 2007-10-10 13:52:05 -0500 |
commit | dfc517b05395d925a4d7b1ce9633a849f9468e70 (patch) | |
tree | a81c020c89022980e6fbb68116648da217fbb0fc /source4/lib/util/pidfile.c | |
parent | 80c8a522861068e7b0974986936f65052dd6f70f (diff) | |
download | samba-dfc517b05395d925a4d7b1ce9633a849f9468e70.tar.gz samba-dfc517b05395d925a4d7b1ce9633a849f9468e70.tar.bz2 samba-dfc517b05395d925a4d7b1ce9633a849f9468e70.zip |
r13658: More moving around of files:
- Collect the generic utility functions into a lib/util/ (a la GLib is
for the GNOME folks)
- Remove even more files from include/
(This used to be commit ba62880f5b05c2a505dc7f54676b231197a7e707)
Diffstat (limited to 'source4/lib/util/pidfile.c')
-rw-r--r-- | source4/lib/util/pidfile.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/source4/lib/util/pidfile.c b/source4/lib/util/pidfile.c new file mode 100644 index 0000000000..9a7c197f70 --- /dev/null +++ b/source4/lib/util/pidfile.c @@ -0,0 +1,116 @@ +/* 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 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 program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#include "includes.h" +#include "system/filesys.h" + +#ifndef O_NONBLOCK +#define O_NONBLOCK +#endif + +/* return the pid in a pidfile. return 0 if the process (or pidfile) + does not exist */ +pid_t pidfile_pid(const char *name) +{ + int fd; + char pidstr[20]; + uint_t ret; + char *pidFile; + + asprintf(&pidFile, "%s/%s.pid", lp_piddir(), name); + + 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 = atoi(pidstr); + + if (!process_exists((pid_t)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 (pid_t)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 *name) +{ + int fd; + char buf[20]; + char *pidFile; + pid_t pid; + + asprintf(&pidFile, "%s/%s.pid", lp_piddir(), name); + + pid = pidfile_pid(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); + } + + 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", (uint_t) 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); +} |