2 Create and remove pidfile
4 Copyright (C) Amitay Isaacs 2016
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, see <http://www.gnu.org/licenses/>.
21 #include "system/filesys.h"
25 #include "common/pidfile.h"
27 struct pidfile_context {
33 static int pidfile_context_destructor(struct pidfile_context *pid_ctx);
35 int pidfile_create(TALLOC_CTX *mem_ctx, const char *pidfile,
36 struct pidfile_context **result)
38 struct pidfile_context *pid_ctx;
45 pid_ctx = talloc_zero(mem_ctx, struct pidfile_context);
46 if (pid_ctx == NULL) {
50 pid_ctx->pidfile = talloc_strdup(pid_ctx, pidfile);
51 if (pid_ctx->pidfile == NULL) {
56 pid_ctx->pid = getpid();
58 fd = open(pidfile, O_CREAT|O_WRONLY|O_NONBLOCK, 0644);
66 lck = (struct flock) {
72 ret = fcntl(fd, F_SETLK, &lck);
73 } while ((ret == -1) && (errno == EINTR));
81 ret = ftruncate(fd, 0);
82 } while ((ret == -1) && (errno == EINTR));
89 len = snprintf(tmp, sizeof(tmp), "%u\n", pid_ctx->pid);
96 nwritten = write(fd, tmp, len);
97 } while ((nwritten == -1) && (errno == EINTR));
99 if ((nwritten == -1) || (nwritten != len)) {
104 talloc_set_destructor(pid_ctx, pidfile_context_destructor);
114 talloc_free(pid_ctx);
118 static int pidfile_context_destructor(struct pidfile_context *pid_ctx)
123 if (getpid() != pid_ctx->pid) {
127 lck = (struct flock) {
129 .l_whence = SEEK_SET,
132 (void) unlink(pid_ctx->pidfile);
135 ret = fcntl(pid_ctx->fd, F_SETLK, &lck);
136 } while ((ret == -1) && (errno == EINTR));
139 ret = close(pid_ctx->fd);
140 } while ((ret == -1) && (errno == EINTR));