X-Git-Url: https://gerrit.automotivelinux.org/gerrit/gitweb?a=blobdiff_plain;f=src%2Fjobs.c;h=8725d00e6cdd4246e5014ab7b6124ad6bb74ca12;hb=b48b736097a222fdf8c6f1a33c922ee7d7bcd633;hp=f7acebf4b6f7fd1adb90b56244a4497d0812c9cd;hpb=162436f4ffbbf63d867735f7de5b78dcd684f890;p=src%2Fapp-framework-binder.git

diff --git a/src/jobs.c b/src/jobs.c
index f7acebf4..8725d00e 100644
--- a/src/jobs.c
+++ b/src/jobs.c
@@ -18,6 +18,7 @@
 #define _GNU_SOURCE
 
 #include <stdlib.h>
+#include <stdint.h>
 #include <unistd.h>
 #include <signal.h>
 #include <time.h>
@@ -26,43 +27,84 @@
 #include <errno.h>
 #include <assert.h>
 
+#include <systemd/sd-event.h>
+
 #include "jobs.h"
 #include "sig-monitor.h"
 #include "verbose.h"
 
-/* describes pending job */
+#if 0
+#define _alert_ "do you really want to remove monitoring?"
+#define sig_monitor_init_timeouts()  ((void)0)
+#define sig_monitor_clean_timeouts() ((void)0)
+#define sig_monitor(to,cb,arg)       (cb(0,arg))
+#endif
+
+#define EVENT_TIMEOUT_TOP  	((uint64_t)-1)
+#define EVENT_TIMEOUT_CHILD	((uint64_t)10000)
+
+/** Internal shortcut for callback */
+typedef void (*job_cb_t)(int, void*);
+
+/** Description of a pending job */
 struct job
 {
-	struct job *next;   /* link to the next job enqueued */
-	void *group;        /* group of the request */
-	void (*callback)(int,void*,void*,void*);     /* processing callback */
-	void *arg1;         /* first arg */
-	void *arg2;         /* second arg */
-	void *arg3;         /* second arg */
-	int timeout;        /* timeout in second for processing the request */
-	int blocked;        /* is an other request blocking this one ? */
+	struct job *next;    /**< link to the next job enqueued */
+	void *group;         /**< group of the request */
+	job_cb_t callback;   /**< processing callback */
+	void *arg;           /**< argument */
+	int timeout;         /**< timeout in second for processing the request */
+	unsigned blocked: 1; /**< is an other request blocking this one ? */
+	unsigned dropped: 1; /**< is removed ? */
 };
 
-/** control of threads */
+/** Description of handled event loops */
+struct events
+{
+	struct events *next;
+	struct sd_event *event;
+	uint64_t timeout;
+	unsigned runs: 1;
+};
+
+/** Description of threads */
 struct thread
 {
-	struct thread *next;  /**< next thread of the list */
-	struct thread *upper; /**< upper same thread */
-	struct job *job;      /**< currently processed job */
-	pthread_t tid;        /**< the thread id */
-	unsigned stop: 1;     /**< stop requested */
-	unsigned lowered: 1;  /**< has a lower same thread */
+	struct thread *next;   /**< next thread of the list */
+	struct thread *upper;  /**< upper same thread */
+	struct job *job;       /**< currently processed job */
+	struct events *events; /**< currently processed job */
+	pthread_t tid;         /**< the thread id */
+	unsigned stop: 1;      /**< stop requested */
+	unsigned lowered: 1;   /**< has a lower same thread */
+	unsigned waits: 1;     /**< is waiting? */
 };
 
+/**
+ * Description of synchonous callback
+ */
+struct sync
+{
+	struct thread thread;	/**< thread loop data */
+	union {
+		void (*callback)(int, void*);	/**< the synchronous callback */
+		void (*enter)(int signum, void *closure, struct jobloop *jobloop);
+				/**< the entering synchronous routine */
+	};
+	void *arg;		/**< the argument of the callback */
+};
+
+
 /* synchronisation of threads */
 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t  cond = PTHREAD_COND_INITIALIZER;
 
-/* count allowed, started and running threads */
+/* count allowed, started and waiting threads */
 static int allowed = 0; /** allowed count of threads */
 static int started = 0; /** started count of threads */
-static int running = 0; /** running count of threads */
-static int remains = 0; /** remaining count of jobs that can be created */
+static int waiting = 0; /** waiting count of threads */
+static int remains = 0; /** allowed count of waiting jobs */
+static int nevents = 0; /** count of events */
 
 /* list of threads */
 static struct thread *threads;
@@ -70,26 +112,22 @@ static _Thread_local struct thread *current;
 
 /* queue of pending jobs */
 static struct job *first_job;
-static struct job *first_evloop;
+static struct events *first_events;
 static struct job *free_jobs;
 
 /**
  * Create a new job with the given parameters
- * @param group the group of the job
- * @param timeout the timeout of the job (0 if none)
+ * @param group    the group of the job
+ * @param timeout  the timeout of the job (0 if none)
  * @param callback the function that achieves the job
- * @param arg1 the first argument of the callback
- * @param arg2 the second argument of the callback
- * @param arg3 the third argument of the callback
+ * @param arg      the argument of the callback
  * @return the created job unblock or NULL when no more memory
  */
 static struct job *job_create(
 		void *group,
 		int timeout,
-		void (*callback)(int, void*, void *, void*),
-		void *arg1,
-		void *arg2,
-		void *arg3)
+		job_cb_t callback,
+		void *arg)
 {
 	struct job *job;
 
@@ -111,74 +149,69 @@ static struct job *job_create(
 	job->group = group;
 	job->timeout = timeout;
 	job->callback = callback;
-	job->arg1 = arg1;
-	job->arg2 = arg2;
-	job->arg3 = arg3;
+	job->arg = arg;
 	job->blocked = 0;
+	job->dropped = 0;
 end:
 	return job;
 }
 
 /**
- * Adds 'job1' and 'job2' at the end of the list of jobs, marking it
+ * Adds 'job' at the end of the list of jobs, marking it
  * as blocked if an other job with the same group is pending.
- * @param job1 the first job to add
- * @param job2 the second job to add or NULL
+ * @param job the job to add
  */
-static void job_add2(struct job *job1, struct job *job2)
+static void job_add(struct job *job)
 {
-	void *group1, *group2, *group;
+	void *group;
 	struct job *ijob, **pjob;
 
 	/* prepare to add */
-	group1 = job1->group;
-	job1->next = job2;
-	if (!job2)
-		group2 = NULL;
-	else {
-		job2->next = NULL;
-		group2 = job2->group;
-		if (group2 && group2 == group1)
-			job2->blocked = 1;
-	}
+	group = job->group;
+	job->next = NULL;
 
-	/* search end and blackers */
+	/* search end and blockers */
 	pjob = &first_job;
 	ijob = first_job;
 	while (ijob) {
-		group = ijob->group;
-		if (group) {
-			if (group == group1)
-				job1->blocked = 1;
-			if (group == group2)
-				job2->blocked = 1;
-		}
+		if (group && ijob->group == group)
+			job->blocked = 1;
 		pjob = &ijob->next;
 		ijob = ijob->next;
 	}
 
 	/* queue the jobs */
-	*pjob = job1;
+	*pjob = job;
 }
 
 /**
  * Get the next job to process or NULL if none.
- * The returned job if any isn't removed from
- * the list of jobs.
- * @return the job to process
+ * @return the first job that isn't blocked or NULL
  */
 static inline struct job *job_get()
 {
-	struct job *job;
-
-	job = first_job;
+	struct job *job = first_job;
 	while (job && job->blocked)
 		job = job->next;
 	return job;
 }
 
 /**
- * Releases the processed 'job'
+ * Get the next events to process or NULL if none.
+ * @return the first events that isn't running or NULL
+ */
+static inline struct events *events_get()
+{
+	struct events *events = first_events;
+	while (events && events->runs)
+		events = events->next;
+	return events;
+}
+
+/**
+ * Releases the processed 'job': removes it
+ * from the list of jobs and unblock the first
+ * pending job of the same group if any.
  * @param job the job to release
  */
 static inline void job_release(struct job *job)
@@ -210,94 +243,140 @@ static inline void job_release(struct job *job)
 	free_jobs = job;
 }
 
-/** monitored call to the job */
-static void job_call(int signum, void *arg)
+/**
+ * Monitored cancel callback for a job.
+ * This function is called by the monitor
+ * to cancel the job when the safe environment
+ * is set.
+ * @param signum 0 on normal flow or the number
+ *               of the signal that interrupted the normal
+ *               flow, isn't used
+ * @param arg    the job to run
+ */
+static void job_cancel(int signum, void *arg)
 {
 	struct job *job = arg;
-	job->callback(signum, job->arg1, job->arg2, job->arg3);
+	job->callback(SIGABRT, job->arg);
 }
 
-/** monitored cancel of the job */
-static void job_cancel(int signum, void *arg)
+/**
+ * Monitored normal callback for events.
+ * This function is called by the monitor
+ * to run the event loop when the safe environment
+ * is set.
+ * @param signum 0 on normal flow or the number
+ *               of the signal that interrupted the normal
+ *               flow
+ * @param arg     the events to run
+ */
+static void events_call(int signum, void *arg)
 {
-	job_call(SIGABRT, arg);
+	struct events *events = arg;
+	if (!signum)
+		sd_event_run(events->event, events->timeout);
 }
 
-/* main loop of processing threads */
-static void thread_run(struct thread *me)
+/**
+ * Main processing loop of threads processing jobs.
+ * The loop must be called with the mutex locked
+ * and it returns with the mutex locked.
+ * @param me the description of the thread to use
+ * TODO: how are timeout handled when reentering?
+ */
+static void thread_run(volatile struct thread *me)
 {
 	struct thread **prv;
 	struct job *job;
+	struct events *events;
+	uint64_t evto;
 
-	/* init */
+	/* initialize description of itself and link it in the list */
 	me->tid = pthread_self();
 	me->stop = 0;
 	me->lowered = 0;
+	me->waits = 0;
 	me->upper = current;
-	if (current)
+	if (current) {
 		current->lowered = 1;
-	else
+		evto = EVENT_TIMEOUT_CHILD;
+	} else {
+		started++;
 		sig_monitor_init_timeouts();
-	current = me;
+		evto = EVENT_TIMEOUT_TOP;
+	}
 	me->next = threads;
-	threads = me;
+	threads = (struct thread*)me;
+	current = (struct thread*)me;
 
 	/* loop until stopped */
-	running++;
+	me->events = NULL;
 	while (!me->stop) {
 		/* get a job */
-		job = job_get();
-		if (!job && first_job && running == 0) {
-			/* sad situation!! should not happen */
-			ERROR("threads are blocked!");
-			job = first_job;
-			first_job = job->next;
-		}
+		job = job_get(first_job);
 		if (job) {
+			/* prepare running the job */
+			remains++; /* increases count of job that can wait */
+			job->blocked = 1; /* mark job as blocked */
+			me->job = job; /* record the job (only for terminate) */
+
 			/* run the job */
-			remains++;
-			job->blocked = 1;
-			me->job = job;
 			pthread_mutex_unlock(&mutex);
-			sig_monitor(job->timeout, job_call, job);
+			sig_monitor(job->timeout, job->callback, job->arg);
 			pthread_mutex_lock(&mutex);
+
+			/* release the run job */
 			job_release(job);
+
+			/* release event if any */
+			events = me->events;
+			if (events) {
+				events->runs = 0;
+				me->events = NULL;
+			}
 		} else {
-			/* no job, check evloop */
-			job = first_evloop;
-			if (job) {
-				/* evloop */
-				first_evloop = job->next;
+			/* no job, check events */
+			events = events_get();
+			if (events) {
+				/* run the events */
+				events->runs = 1;
+				events->timeout = evto;
+				me->events = events;
 				pthread_mutex_unlock(&mutex);
-				sig_monitor(job->timeout, job_call, job);
+				sig_monitor(0, events_call, events);
 				pthread_mutex_lock(&mutex);
-				job->next = first_evloop;
-				first_evloop = job;
+				events->runs = 0;
+				me->events = NULL;
 			} else {
-				/* no job and not evloop */
-				running--;
+				/* no job and not events */
+				waiting++;
+				me->waits = 1;
 				pthread_cond_wait(&cond, &mutex);
-				running++;
+				me->waits = 0;
+				waiting--;
 			}
 		}
 	}
-	running--;
 
-	/* uninit */
+	/* unlink the current thread and cleanup */
 	prv = &threads;
 	while (*prv != me)
 		prv = &(*prv)->next;
 	*prv = me->next;
 	current = me->upper;
-	if (current)
+	if (current) {
 		current->lowered = 0;
-	else
+	} else {
 		sig_monitor_clean_timeouts();
-	pthread_mutex_unlock(&mutex);
+		started--;
+	}
 }
 
-/* main loop of processing threads */
-static void *thread_create(void *data)
+/**
+ * Entry point for created threads.
+ * @param data not used
+ * @return NULL
+ */
+static void *thread_main(void *data)
 {
 	struct thread me;
 
@@ -307,73 +386,46 @@ static void *thread_create(void *data)
 	return NULL;
 }
 
-/* start a new thread */
+/**
+ * Starts a new thread
+ * @return 0 in case of success or -1 in case of error
+ */
 static int start_one_thread()
 {
 	pthread_t tid;
 	int rc;
 
-	assert(started < allowed);
-
-	started++;
-	rc = pthread_create(&tid, NULL, thread_create, NULL);
+	rc = pthread_create(&tid, NULL, thread_main, NULL);
 	if (rc != 0) {
-		started--;
-		errno = rc;
+		/* errno = rc; */
 		WARNING("not able to start thread: %m");
 		rc = -1;
 	}
 	return rc;
 }
 
-static int start_one_thread_if_needed()
-{
-	int rc;
-
-	if (started == running && started < allowed) {
-		/* all threads are busy and a new can be started */
-		rc = start_one_thread();
-		if (rc < 0 && started == 0)
-			return rc; /* no thread available */
-	}
-	return 0;
-}
-
-int jobs_queue0(
-		void *group,
-		int timeout,
-		void (*callback)(int signum))
-{
-	return jobs_queue3(group, timeout, (void(*)(int,void*,void*,void*))callback, NULL, NULL, NULL);
-}
-
+/**
+ * Queues a new asynchronous job represented by 'callback' and 'arg'
+ * for the 'group' and the 'timeout'.
+ * Jobs are queued FIFO and are possibly executed in parallel
+ * concurrently except for job of the same group that are
+ * executed sequentially in FIFO order.
+ * @param group    The group of the job or NULL when no group.
+ * @param timeout  The maximum execution time in seconds of the job
+ *                 or 0 for unlimited time.
+ * @param callback The function to execute for achieving the job.
+ *                 Its first parameter is either 0 on normal flow
+ *                 or the signal number that broke the normal flow.
+ *                 The remaining parameter is the parameter 'arg1'
+ *                 given here.
+ * @param arg      The second argument for 'callback'
+ * @return 0 in case of success or -1 in case of error
+ */
 int jobs_queue(
 		void *group,
 		int timeout,
 		void (*callback)(int, void*),
 		void *arg)
-{
-	return jobs_queue3(group, timeout, (void(*)(int,void*,void*,void*))callback, arg, NULL, NULL);
-}
-
-int jobs_queue2(
-		void *group,
-		int timeout,
-		void (*callback)(int, void*, void*),
-		void *arg1,
-		void *arg2)
-{
-	return jobs_queue3(group, timeout, (void(*)(int,void*,void*,void*))callback, arg1, arg2, NULL);
-}
-
-/* queue the job to the 'callback' using a separate thread if available */
-int jobs_queue3(
-		void *group,
-		int timeout,
-		void (*callback)(int, void*, void *, void*),
-		void *arg1,
-		void *arg2,
-		void *arg3)
 {
 	const char *info;
 	struct job *job;
@@ -382,7 +434,7 @@ int jobs_queue3(
 	pthread_mutex_lock(&mutex);
 
 	/* allocates the job */
-	job = job_create(group, timeout, callback, arg1, arg2, arg3);
+	job = job_create(group, timeout, callback, arg);
 	if (!job) {
 		errno = ENOMEM;
 		info = "out of memory";
@@ -397,20 +449,22 @@ int jobs_queue3(
 	}
 
 	/* start a thread if needed */
-	rc = start_one_thread_if_needed();
-	if (rc < 0) {
-		/* failed to start threading */
-		info = "can't start first thread";
-		goto error2;
+	if (waiting == 0 && started < allowed) {
+		/* all threads are busy and a new can be started */
+		rc = start_one_thread();
+		if (rc < 0 && started == 0) {
+			info = "can't start first thread";
+			goto error2;
+		}
 	}
 
 	/* queues the job */
 	remains--;
-	job_add2(job, NULL);
-	pthread_mutex_unlock(&mutex);
+	job_add(job);
 
 	/* signal an existing job */
 	pthread_cond_signal(&cond);
+	pthread_mutex_unlock(&mutex);
 	return 0;
 
 error2:
@@ -422,116 +476,289 @@ error:
 	return -1;
 }
 
-/* initialise the threads */
-int jobs_init(int allowed_count, int start_count, int waiter_count)
+/**
+ * Internal helper function for 'jobs_enter'.
+ * @see jobs_enter, jobs_leave
+ */
+static void enter_cb(int signum, void *closure)
 {
-	/* records the allowed count */
-	allowed = allowed_count;
-	started = 0;
-	running = 0;
-	remains = waiter_count;
+	struct sync *sync = closure;
+	sync->enter(signum, sync->arg, (void*)&sync->thread);
+}
+
+/**
+ * Internal helper function for 'jobs_call'.
+ * @see jobs_call
+ */
+static void call_cb(int signum, void *closure)
+{
+	struct sync *sync = closure;
+	sync->callback(signum, sync->arg);
+	jobs_leave((void*)&sync->thread);
+}
+
+/**
+ * Internal helper for synchronous jobs. It enters
+ * a new thread loop for evaluating the given job
+ * as recorded by the couple 'sync_cb' and 'sync'.
+ * @see jobs_call, jobs_enter, jobs_leave
+ */
+static int do_sync(
+		void *group,
+		int timeout,
+		void (*sync_cb)(int signum, void *closure),
+		struct sync *sync
+)
+{
+	struct job *job;
 
-	/* start at least one thread */
 	pthread_mutex_lock(&mutex);
-	while (started < start_count && start_one_thread() == 0);
-	pthread_mutex_unlock(&mutex);
 
-	/* end */
-	return -(started != start_count);
+	/* allocates the job */
+	job = job_create(group, timeout, sync_cb, sync);
+	if (!job) {
+		ERROR("out of memory");
+		errno = ENOMEM;
+		pthread_mutex_unlock(&mutex);
+		return -1;
+	}
+
+	/* queues the job */
+	job_add(job);
+
+	/* run until stopped */
+	thread_run(&sync->thread);
+	pthread_mutex_unlock(&mutex);
+	return 0;
 }
 
-int jobs_invoke0(
+/**
+ * Enter a synchronisation point: activates the job given by 'callback'
+ * and 'closure' using 'group' and 'timeout' to control sequencing and
+ * execution time.
+ * @param group the group for sequencing jobs
+ * @param timeout the time in seconds allocated to the job
+ * @param callback the callback that will handle the job.
+ *                 it receives 3 parameters: 'signum' that will be 0
+ *                 on normal flow or the catched signal number in case
+ *                 of interrupted flow, the context 'closure' as given and
+ *                 a 'jobloop' reference that must be used when the job is
+ *                 terminated to unlock the current execution flow.
+ * @param arg the argument to the callback
+ * @return 0 on success or -1 in case of error
+ */
+int jobs_enter(
+		void *group,
 		int timeout,
-		void (*callback)(int signum))
+		void (*callback)(int signum, void *closure, struct jobloop *jobloop),
+		void *closure
+)
 {
-	return jobs_invoke3(timeout, (void(*)(int,void*,void*,void*))callback, NULL, NULL, NULL);
+	struct sync sync;
+
+	sync.enter = callback;
+	sync.arg = closure;
+	return do_sync(group, timeout, enter_cb, &sync);
 }
 
-int jobs_invoke(
-		int timeout,
-		void (*callback)(int, void*),
-		void *arg)
+/**
+ * Unlocks the execution flow designed by 'jobloop'.
+ * @param jobloop indication of the flow to unlock
+ * @return 0 in case of success of -1 on error
+ */
+int jobs_leave(struct jobloop *jobloop)
 {
-	return jobs_invoke3(timeout, (void(*)(int,void*,void*,void*))callback, arg, NULL, NULL);
+	struct thread *t;
+
+	pthread_mutex_lock(&mutex);
+	t = threads;
+	while (t && t != (struct thread*)jobloop)
+		t = t->next;
+	if (!t) {
+		errno = EINVAL;
+	} else {
+		t->stop = 1;
+		if (t->waits)
+			pthread_cond_broadcast(&cond);
+	}
+	pthread_mutex_unlock(&mutex);
+	return -!t;
 }
 
-int jobs_invoke2(
+/**
+ * Calls synchronously the job represented by 'callback' and 'arg1'
+ * for the 'group' and the 'timeout' and waits for its completion.
+ * @param group    The group of the job or NULL when no group.
+ * @param timeout  The maximum execution time in seconds of the job
+ *                 or 0 for unlimited time.
+ * @param callback The function to execute for achieving the job.
+ *                 Its first parameter is either 0 on normal flow
+ *                 or the signal number that broke the normal flow.
+ *                 The remaining parameter is the parameter 'arg1'
+ *                 given here.
+ * @param arg      The second argument for 'callback'
+ * @return 0 in case of success or -1 in case of error
+ */
+int jobs_call(
+		void *group,
 		int timeout,
-		void (*callback)(int, void*, void*),
-		void *arg1,
-		void *arg2)
+		void (*callback)(int, void*),
+		void *arg)
 {
-	return jobs_invoke3(timeout, (void(*)(int,void*,void*,void*))callback, arg1, arg2, NULL);
+	struct sync sync;
+
+	sync.callback = callback;
+	sync.arg = arg;
+
+	return do_sync(group, timeout, call_cb, &sync);
 }
 
-static void unlock_invoker(int signum, void *arg1, void *arg2, void *arg3)
+/**
+ * Gets a sd_event item for the current thread.
+ * @return a sd_event or NULL in case of error
+ */
+struct sd_event *jobs_get_sd_event()
 {
-	struct thread *t = arg1;
+	struct events *events;
+	struct thread *me;
+	int rc;
+
 	pthread_mutex_lock(&mutex);
-	t->stop = 1;
+
+	/* search events on stack */
+	me = current;
+	while (me && !me->events)
+		me = me->upper;
+	if (me)
+		/* return the stacked events */
+		events = me->events;
+	else {
+		/* search an available events */
+		events = events_get();
+		if (!events) {
+			/* not found, check if creation possible */
+			if (nevents >= allowed) {
+				ERROR("not possible to add a new event");
+				events = NULL;
+			} else {
+				events = malloc(sizeof *events);
+				if (events && (rc = sd_event_new(&events->event)) >= 0) {
+					if (nevents < started || start_one_thread() >= 0) {
+						events->runs = 0;
+						events->next = first_events;
+						first_events = events;
+					} else {
+						ERROR("can't start thread for events");
+						sd_event_unref(events->event);
+						free(events);
+						events = NULL;
+					}
+				} else {
+					if (!events) {
+						ERROR("out of memory");
+						errno = ENOMEM;
+					} else {
+						free(events);
+						ERROR("creation of sd_event failed: %m");
+						events = NULL;
+						errno = -rc;
+					} 
+				}
+			}
+		}
+		if (events) {
+			/* */
+			me = current;
+			if (me) {
+				events->runs = 1;
+				me->events = events;
+			} else {
+				WARNING("event returned for unknown thread!");
+			}
+		}
+	}
 	pthread_mutex_unlock(&mutex);
+	return events ? events->event : NULL;
 }
 
-/* invoke the job to the 'callback' using a separate thread if available */
-int jobs_invoke3(
-		int timeout,
-		void (*callback)(int, void*, void *, void*),
-		void *arg1,
-		void *arg2,
-		void *arg3)
+/**
+ * Enter the jobs processing loop.
+ * @param allowed_count Maximum count of thread for jobs including this one
+ * @param start_count   Count of thread to start now, must be lower.
+ * @param waiter_count  Maximum count of jobs that can be waiting.
+ * @param start         The start routine to activate (can't be NULL)
+ * @return 0 in case of success or -1 in case of error.
+ */
+int jobs_start(int allowed_count, int start_count, int waiter_count, void (*start)())
 {
-	const char *info;
-	struct job *job1, *job2;
-	int rc;
+	int rc, launched;
 	struct thread me;
-	
+	struct job *job;
+
+	assert(allowed_count >= 1);
+	assert(start_count >= 0);
+	assert(waiter_count > 0);
+	assert(start_count <= allowed_count);
+
+	rc = -1;
 	pthread_mutex_lock(&mutex);
 
-	/* allocates the job */
-	job1 = job_create(&me, timeout, callback, arg1, arg2, arg3);
-	job2 = job_create(&me, 0, unlock_invoker, &me, NULL, NULL);
-	if (!job1 || !job2) {
-		errno = ENOMEM;
-		info = "out of memory";
+	/* check whether already running */
+	if (current || allowed) {
+		ERROR("thread already started");
+		errno = EINVAL;
 		goto error;
 	}
 
-	/* start a thread if needed */
-	rc = start_one_thread_if_needed();
-	if (rc < 0) {
-		/* failed to start threading */
-		info = "can't start first thread";
+	/* start */
+	if (sig_monitor_init() < 0) {
+		ERROR("failed to initialise signal handlers");
 		goto error;
 	}
 
-	/* queues the job */
-	job_add2(job1, job2);
-
-	/* run untill stopped */
-	thread_run(&me);
-	pthread_mutex_unlock(&mutex);
-	return 0;
+	/* records the allowed count */
+	allowed = allowed_count;
+	started = 0;
+	waiting = 0;
+	remains = waiter_count;
 
-error:
-	if (job1) {
-		job1->next = free_jobs;
-		free_jobs = job1;
+	/* start at least one thread */
+	launched = 0;
+	while ((launched + 1) < start_count) {
+		if (start_one_thread() != 0) {
+			ERROR("Not all threads can be started");
+			goto error;
+		}
+		launched++;
 	}
-	if (job2) {
-		job2->next = free_jobs;
-		free_jobs = job2;
+
+	/* queue the start job */
+	job = job_create(NULL, 0, (job_cb_t)start, NULL);
+	if (!job) {
+		ERROR("out of memory");
+		errno = ENOMEM;
+		goto error;
 	}
-	ERROR("can't process job with threads: %s, %m", info);
+	job_add(job);
+	remains--;
+
+	/* run until end */
+	thread_run(&me);
+	rc = 0;
+error:
 	pthread_mutex_unlock(&mutex);
-	return -1;
+	return rc;
 }
 
-/* terminate all the threads and all pending requests */
+/**
+ * Terminate all the threads and cancel all pending jobs.
+ */
 void jobs_terminate()
 {
 	struct job *job, *head, *tail;
-	pthread_t me, other;
+	pthread_t me, *others;
 	struct thread *t;
+	int count;
 
 	/* how am i? */
 	me = pthread_self();
@@ -539,23 +766,42 @@ void jobs_terminate()
 	/* request all threads to stop */
 	pthread_mutex_lock(&mutex);
 	allowed = 0;
-	for(;;) {
-		/* search the next thread to stop */
-		t = threads;
-		while (t && pthread_equal(t->tid, me))
-			t = t->next;
-		if (!t)
-			break;
-		/* stop it */
-		other = t->tid;
+
+	/* count the number of threads */
+	count = 0;
+	t = threads;
+	while (t) {
+		if (!t->upper && !pthread_equal(t->tid, me))
+			count++;
+		t = t->next;
+	}
+
+	/* fill the array of threads */
+	others = alloca(count * sizeof *others);
+	count = 0;
+	t = threads;
+	while (t) {
+		if (!t->upper && !pthread_equal(t->tid, me))
+			others[count++] = t->tid;
+		t = t->next;
+	}
+
+	/* stops the threads */
+	t = threads;
+	while (t) {
 		t->stop = 1;
-		pthread_mutex_unlock(&mutex);
-		pthread_cond_broadcast(&cond);
-		pthread_join(other, NULL);
-		pthread_mutex_lock(&mutex);
+		t = t->next;
 	}
 
+	/* wait the threads */
+	pthread_cond_broadcast(&cond);
+	pthread_mutex_unlock(&mutex);
+	while (count)
+		pthread_join(others[--count], NULL);
+	pthread_mutex_lock(&mutex);
+
 	/* cancel pending jobs of other threads */
+	remains = 0;
 	head = first_job;
 	first_job = NULL;
 	tail = NULL;
@@ -587,42 +833,3 @@ void jobs_terminate()
 	pthread_mutex_unlock(&mutex);
 }
 
-int jobs_add_event_loop(void *key, int timeout, void (*evloop)(int signum, void*), void *closure)
-{
-	struct job *job;
-
-	pthread_mutex_lock(&mutex);
-	job = job_create(key, timeout, (void (*)(int,  void *, void *, void *))evloop, closure, NULL, NULL);
-	if (job) {
-		/* adds the loop */
-		job->next = first_evloop;
-		first_evloop = job;
-
-		/* signal the loop */
-		pthread_cond_signal(&cond);
-	}
-	pthread_mutex_unlock(&mutex);
-	return -!job;
-}
-
-int jobs_add_me()
-{
-	struct thread me;
-
-	/* check whether already running */
-	if (current) {
-		ERROR("thread already running");
-		errno = EINVAL;
-		return -1;
-	}
-
-	/* allowed... */
-	pthread_mutex_lock(&mutex);
-	allowed++;
-	thread_run(&me);
-	allowed--;
-	pthread_mutex_unlock(&mutex);
-	return 0;
-}
-
-