getopt \
strtonum \
resource trans res-fd res-mem res-subpool res-mempool res-eltpool \
- daemon
+ daemon daemon-ctrl
LIBUCW_MAIN_INCLUDES= \
lib.h log.h threads.h time.h \
--- /dev/null
+/*
+ * UCW Library -- Daemon Control
+ *
+ * (c) 2012 Martin Mares <mj@ucw.cz>
+ *
+ * This software may be freely distributed and used according to the terms
+ * of the GNU Lesser General Public License.
+ */
+
+#include <ucw/lib.h>
+#include <ucw/daemon.h>
+#include <ucw/process.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <signal.h>
+#include <sys/file.h>
+#include <sys/wait.h>
+
+static enum daemon_control_status
+daemon_control_err(struct daemon_control_params *dc, char *msg, ...)
+{
+ va_list args;
+ va_start(args, msg);
+ vsnprintf(dc->error_msg, DAEMON_ERR_LEN, msg, args);
+ va_end(args);
+ return DAEMON_STATUS_ERROR;
+}
+
+static int
+daemon_read_pid(struct daemon_control_params *dc, int will_wait)
+{
+ int pid_fd = open(dc->pid_file, O_RDONLY);
+ if (pid_fd < 0)
+ {
+ if (errno == ENOENT)
+ return 0;
+ daemon_control_err(dc, "Cannot open PID file `%s': %m", dc->pid_file);
+ return -1;
+ }
+
+ if (flock(pid_fd, LOCK_EX | (will_wait ? 0 : LOCK_NB)) >= 0)
+ {
+ // The lock file is stale
+ close(pid_fd);
+ return 0;
+ }
+
+ if (errno != EINTR && errno != EWOULDBLOCK)
+ {
+ daemon_control_err(dc, "Cannot lock PID file `%s': %m", dc->pid_file);
+ goto fail;
+ }
+
+ char buf[16];
+ int n = read(pid_fd, buf, sizeof(buf));
+ if (n < 0)
+ {
+ daemon_control_err(dc, "Error reading `%s': %m", dc->pid_file);
+ goto fail;
+ }
+ if (n == (int) sizeof(buf))
+ {
+ daemon_control_err(dc, "PID file `%s' is too long", dc->pid_file);
+ goto fail;
+ }
+ buf[n] = 0;
+ int pid = atoi(buf);
+ if (!pid)
+ {
+ daemon_control_err(dc, "PID file `%s' does not contain a valid PID", dc->pid_file);
+ goto fail;
+ }
+ close(pid_fd);
+ return pid;
+
+fail:
+ close(pid_fd);
+ return -1;
+}
+
+enum daemon_control_status
+daemon_control(struct daemon_control_params *dc)
+{
+ enum daemon_control_status st = DAEMON_STATUS_ERROR;
+
+ int guard_fd = open(dc->guard_file, O_RDWR | O_CREAT, 0666);
+ if (guard_fd < 0)
+ return daemon_control_err(dc, "Cannot open guard file `%s': %m", dc->guard_file);
+ if (flock(guard_fd, LOCK_EX) < 0)
+ return daemon_control_err(dc, "Cannot lock guard file `%s': %m", dc->guard_file);
+
+ // Read the PID file
+ int pid = daemon_read_pid(dc, 0);
+ if (pid < 0)
+ goto done;
+
+ switch (dc->action)
+ {
+ case DAEMON_CONTROL_CHECK:
+ if (pid)
+ st = DAEMON_STATUS_OK;
+ else
+ st = DAEMON_STATUS_NOT_RUNNING;
+ break;
+ case DAEMON_CONTROL_START:
+ if (pid)
+ st = DAEMON_STATUS_ALREADY_DONE;
+ else
+ {
+ pid_t pp = fork();
+ if (pp < 0)
+ {
+ daemon_control_err(dc, "Cannot fork: %m");
+ goto done;
+ }
+ if (pp)
+ {
+ close(guard_fd);
+ execvp(dc->argv[0], dc->argv);
+ fprintf(stderr, "Cannot execute `%s': %m\n", dc->argv[0]);
+ exit(DAEMON_STATUS_ERROR);
+ }
+ int stat;
+ int ec = waitpid(pp, &stat, 0);
+ if (ec < 0)
+ {
+ daemon_control_err(dc, "Cannot wait: %m");
+ goto done;
+ }
+ if (WIFEXITED(stat) && WEXITSTATUS(stat) == DAEMON_STATUS_ERROR)
+ {
+ daemon_control_err(dc, "Cannot execute the daemon");
+ goto done;
+ }
+ char ecmsg[EXIT_STATUS_MSG_SIZE];
+ if (format_exit_status(ecmsg, stat))
+ {
+ daemon_control_err(dc, "Daemon %s", ecmsg);
+ goto done;
+ }
+ pid = daemon_read_pid(dc, 0);
+ if (!pid)
+ daemon_control_err(dc, "Daemon failed to write the PID file `%s'", dc->pid_file);
+ else
+ st = DAEMON_STATUS_OK;
+ }
+ break;
+ case DAEMON_CONTROL_STOP:
+ if (!pid)
+ return DAEMON_STATUS_ALREADY_DONE;
+ int sig = dc->signal ? : SIGTERM;
+ if (kill(pid, sig) < 0)
+ {
+ daemon_control_err(dc, "Cannot send signal %d: %m", dc->signal);
+ goto done;
+ }
+ pid = daemon_read_pid(dc, 1);
+ ASSERT(pid <= 0);
+ if (!pid)
+ st = DAEMON_STATUS_OK;
+ break;
+ case DAEMON_CONTROL_SIGNAL:
+ if (!pid)
+ return DAEMON_STATUS_NOT_RUNNING;
+ if (kill(pid, dc->signal) < 0)
+ daemon_control_err(dc, "Cannot send signal %d: %m", dc->signal);
+ else
+ st = DAEMON_STATUS_OK;
+ break;
+ default:
+ ASSERT(0);
+ }
+
+done:
+ close(guard_fd);
+ return st;
+}
#include <ucw/lib.h>
#include <ucw/daemon.h>
#include <ucw/strtonum.h>
-#include <ucw/process.h>
#include <stdio.h>
#include <stdlib.h>
-#include <stdarg.h>
#include <fcntl.h>
#include <unistd.h>
#include <pwd.h>
#include <grp.h>
#include <errno.h>
-#include <signal.h>
#include <sys/file.h>
-#include <sys/wait.h>
static void
daemon_resolve_ugid(struct daemon_params *dp)
}
}
-static enum daemon_control_status
-daemon_control_err(struct daemon_control_params *dc, char *msg, ...)
-{
- va_list args;
- va_start(args, msg);
- vsnprintf(dc->error_msg, DAEMON_ERR_LEN, msg, args);
- va_end(args);
- return DAEMON_STATUS_ERROR;
-}
-
-static int
-daemon_read_pid(struct daemon_control_params *dc, int will_wait)
-{
- int pid_fd = open(dc->pid_file, O_RDONLY);
- if (pid_fd < 0)
- {
- if (errno == ENOENT)
- return 0;
- daemon_control_err(dc, "Cannot open PID file `%s': %m", dc->pid_file);
- return -1;
- }
-
- if (flock(pid_fd, LOCK_EX | (will_wait ? 0 : LOCK_NB)) >= 0)
- {
- // The lock file is stale
- close(pid_fd);
- return 0;
- }
-
- if (errno != EINTR && errno != EWOULDBLOCK)
- {
- daemon_control_err(dc, "Cannot lock PID file `%s': %m", dc->pid_file);
- goto fail;
- }
-
- char buf[16];
- int n = read(pid_fd, buf, sizeof(buf));
- if (n < 0)
- {
- daemon_control_err(dc, "Error reading `%s': %m", dc->pid_file);
- goto fail;
- }
- if (n == (int) sizeof(buf))
- {
- daemon_control_err(dc, "PID file `%s' is too long", dc->pid_file);
- goto fail;
- }
- buf[n] = 0;
- int pid = atoi(buf);
- if (!pid)
- {
- daemon_control_err(dc, "PID file `%s' does not contain a valid PID", dc->pid_file);
- goto fail;
- }
- close(pid_fd);
- return pid;
-
-fail:
- close(pid_fd);
- return -1;
-}
-
-enum daemon_control_status
-daemon_control(struct daemon_control_params *dc)
-{
- enum daemon_control_status st = DAEMON_STATUS_ERROR;
-
- int guard_fd = open(dc->guard_file, O_RDWR | O_CREAT, 0666);
- if (guard_fd < 0)
- return daemon_control_err(dc, "Cannot open guard file `%s': %m", dc->guard_file);
- if (flock(guard_fd, LOCK_EX) < 0)
- return daemon_control_err(dc, "Cannot lock guard file `%s': %m", dc->guard_file);
-
- // Read the PID file
- int pid = daemon_read_pid(dc, 0);
- if (pid < 0)
- goto done;
-
- switch (dc->action)
- {
- case DAEMON_CONTROL_CHECK:
- if (pid)
- st = DAEMON_STATUS_OK;
- else
- st = DAEMON_STATUS_NOT_RUNNING;
- break;
- case DAEMON_CONTROL_START:
- if (pid)
- st = DAEMON_STATUS_ALREADY_DONE;
- else
- {
- pid_t pp = fork();
- if (pp < 0)
- {
- daemon_control_err(dc, "Cannot fork: %m");
- goto done;
- }
- if (pp)
- {
- close(guard_fd);
- execvp(dc->argv[0], dc->argv);
- fprintf(stderr, "Cannot execute `%s': %m\n", dc->argv[0]);
- exit(DAEMON_STATUS_ERROR);
- }
- int stat;
- int ec = waitpid(pp, &stat, 0);
- if (ec < 0)
- {
- daemon_control_err(dc, "Cannot wait: %m");
- goto done;
- }
- if (WIFEXITED(stat) && WEXITSTATUS(stat) == DAEMON_STATUS_ERROR)
- {
- daemon_control_err(dc, "Cannot execute the daemon");
- goto done;
- }
- char ecmsg[EXIT_STATUS_MSG_SIZE];
- if (format_exit_status(ecmsg, stat))
- {
- daemon_control_err(dc, "Daemon %s", ecmsg);
- goto done;
- }
- pid = daemon_read_pid(dc, 0);
- if (!pid)
- daemon_control_err(dc, "Daemon failed to write the PID file `%s'", dc->pid_file);
- else
- st = DAEMON_STATUS_OK;
- }
- break;
- case DAEMON_CONTROL_STOP:
- if (!pid)
- return DAEMON_STATUS_ALREADY_DONE;
- int sig = dc->signal ? : SIGTERM;
- if (kill(pid, sig) < 0)
- {
- daemon_control_err(dc, "Cannot send signal %d: %m", dc->signal);
- goto done;
- }
- pid = daemon_read_pid(dc, 1);
- ASSERT(pid <= 0);
- if (!pid)
- st = DAEMON_STATUS_OK;
- break;
- case DAEMON_CONTROL_SIGNAL:
- if (!pid)
- return DAEMON_STATUS_NOT_RUNNING;
- if (kill(pid, dc->signal) < 0)
- daemon_control_err(dc, "Cannot send signal %d: %m", dc->signal);
- else
- st = DAEMON_STATUS_OK;
- break;
- default:
- ASSERT(0);
- }
-
-done:
- close(guard_fd);
- return st;
-}
-
#ifdef TEST
static void body(struct daemon_params *dp)
projects / libucw.git / commitdiff