Imported Upstream version 5.0.1

3 files changed, 138 insertions, 221 deletions

diff --git a/src/libstrongswan/processing/jobs/callback_job.c b/src/libstrongswan/processing/jobs/callback_job.c
index 13f22e69c..a5ddc8ff6 100644
--- a/src/libstrongswan/processing/jobs/callback_job.c
+++ b/src/libstrongswan/processing/jobs/callback_job.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009 Tobias Brunner
+ * Copyright (C) 2009-2012 Tobias Brunner
  * Copyright (C) 2007-2011 Martin Willi
  * Copyright (C) 2011 revosec AG
  * Hochschule fuer Technik Rapperswil
@@ -17,10 +17,9 @@
 
 #include "callback_job.h"
 
-#include <semaphore.h>
-
 #include <threading/thread.h>
 #include <threading/condvar.h>
+#include <threading/semaphore.h>
 #include <threading/mutex.h>
 #include <utils/linked_list.h>
 
@@ -52,42 +51,9 @@ struct private_callback_job_t {
 	callback_job_cleanup_t cleanup;
 
 	/**
-	 * thread of the job, if running
-	 */
-	thread_t *thread;
-
-	/**
-	 * mutex to access jobs interna
-	 */
-	mutex_t *mutex;
-
-	/**
-	 * list of associated child jobs
-	 */
-	linked_list_t *children;
-
-	/**
-	 * parent of this job, or NULL
+	 * cancel function
 	 */
-	private_callback_job_t *parent;
-
-	/**
-	 * TRUE if the job got cancelled
-	 */
-	bool cancelled;
-
-	/**
-	 * condvar to synchronize the cancellation/destruction of the job
-	 */
-	condvar_t *destroyable;
-
-	/**
-	 * semaphore to synchronize the termination of the assigned thread.
-	 *
-	 * separately allocated during cancellation, so that we can wait on it
-	 * without risking that it gets freed too early during destruction.
-	 */
-	sem_t *terminated;
+	callback_job_cancel_t cancel;
 
 	/**
 	 * Priority of this job
@@ -95,141 +61,26 @@ struct private_callback_job_t {
 	job_priority_t prio;
 };
 
-/**
- * unregister a child from its parent, if any.
- * note: this->mutex has to be locked
- */
-static void unregister(private_callback_job_t *this)
-{
-	if (this->parent)
-	{
-		this->parent->mutex->lock(this->parent->mutex);
-		if (this->parent->cancelled && !this->cancelled)
-		{
-			/* if the parent has been cancelled but we have not yet, we do not
-			 * unregister until we got cancelled by the parent. */
-			this->parent->mutex->unlock(this->parent->mutex);
-			this->destroyable->wait(this->destroyable, this->mutex);
-			this->parent->mutex->lock(this->parent->mutex);
-		}
-		this->parent->children->remove(this->parent->children, this, NULL);
-		this->parent->mutex->unlock(this->parent->mutex);
-		this->parent = NULL;
-	}
-}
-
 METHOD(job_t, destroy, void,
 	private_callback_job_t *this)
 {
-	this->mutex->lock(this->mutex);
-	unregister(this);
 	if (this->cleanup)
 	{
 		this->cleanup(this->data);
 	}
-	if (this->terminated)
-	{
-		sem_post(this->terminated);
-	}
-	this->children->destroy(this->children);
-	this->destroyable->destroy(this->destroyable);
-	this->mutex->unlock(this->mutex);
-	this->mutex->destroy(this->mutex);
 	free(this);
 }
 
-METHOD(callback_job_t, cancel, void,
+METHOD(job_t, execute, job_requeue_t,
 	private_callback_job_t *this)
 {
-	callback_job_t *child;
-	sem_t *terminated = NULL;
-
-	this->mutex->lock(this->mutex);
-	this->cancelled = TRUE;
-	/* terminate children */
-	while (this->children->get_first(this->children, (void**)&child) == SUCCESS)
-	{
-		this->mutex->unlock(this->mutex);
-		child->cancel(child);
-		this->mutex->lock(this->mutex);
-	}
-	if (this->thread)
-	{
-		/* terminate the thread, if there is currently one executing the job.
-		 * we wait for its termination using a semaphore */
-		this->thread->cancel(this->thread);
-		terminated = this->terminated = malloc_thing(sem_t);
-		sem_init(terminated, 0, 0);
-	}
-	else
-	{
-		/* if the job is currently queued, it gets terminated later.
-		 * we can't wait, because it might not get executed at all.
-		 * we also unregister the queued job manually from its parent (the
-		 * others get unregistered during destruction) */
-		unregister(this);
-	}
-	this->destroyable->signal(this->destroyable);
-	this->mutex->unlock(this->mutex);
-
-	if (terminated)
-	{
-		sem_wait(terminated);
-		sem_destroy(terminated);
-		free(terminated);
-	}
+	return this->callback(this->data);
 }
 
-METHOD(job_t, execute, void,
+METHOD(job_t, cancel, bool,
 	private_callback_job_t *this)
 {
-	bool cleanup = FALSE, requeue = FALSE;
-
-	thread_cleanup_push((thread_cleanup_t)destroy, this);
-
-	this->mutex->lock(this->mutex);
-	this->thread = thread_current();
-	this->mutex->unlock(this->mutex);
-
-	while (TRUE)
-	{
-		this->mutex->lock(this->mutex);
-		if (this->cancelled)
-		{
-			this->mutex->unlock(this->mutex);
-			cleanup = TRUE;
-			break;
-		}
-		this->mutex->unlock(this->mutex);
-		switch (this->callback(this->data))
-		{
-			case JOB_REQUEUE_DIRECT:
-				continue;
-			case JOB_REQUEUE_FAIR:
-			{
-				requeue = TRUE;
-				break;
-			}
-			case JOB_REQUEUE_NONE:
-			default:
-			{
-				cleanup = TRUE;
-				break;
-			}
-		}
-		break;
-	}
-	this->mutex->lock(this->mutex);
-	this->thread = NULL;
-	this->mutex->unlock(this->mutex);
-	/* manually create a cancellation point to avoid that a cancelled thread
-	 * goes back into the thread pool */
-	thread_cancellation_point();
-	if (requeue)
-	{
-		lib->processor->queue_job(lib->processor, &this->public.job);
-	}
-	thread_cleanup_pop(cleanup);
+	return this->cancel(this->data);
 }
 
 METHOD(job_t, get_priority, job_priority_t,
@@ -242,8 +93,8 @@ METHOD(job_t, get_priority, job_priority_t,
  * Described in header.
  */
 callback_job_t *callback_job_create_with_prio(callback_job_cb_t cb, void *data,
-					callback_job_cleanup_t cleanup, callback_job_t *parent,
-					job_priority_t prio)
+				callback_job_cleanup_t cleanup, callback_job_cancel_t cancel,
+				job_priority_t prio)
 {
 	private_callback_job_t *this;
 
@@ -254,24 +105,17 @@ callback_job_t *callback_job_create_with_prio(callback_job_cb_t cb, void *data,
 				.get_priority = _get_priority,
 				.destroy = _destroy,
 			},
-			.cancel = _cancel,
 		},
-		.mutex = mutex_create(MUTEX_TYPE_DEFAULT),
 		.callback = cb,
 		.data = data,
 		.cleanup = cleanup,
-		.children = linked_list_create(),
-		.parent = (private_callback_job_t*)parent,
-		.destroyable = condvar_create(CONDVAR_TYPE_DEFAULT),
+		.cancel = cancel,
 		.prio = prio,
 	);
 
-	/* register us at parent */
-	if (parent)
+	if (cancel)
 	{
-		this->parent->mutex->lock(this->parent->mutex);
-		this->parent->children->insert_last(this->parent->children, this);
-		this->parent->mutex->unlock(this->parent->mutex);
+		this->public.job.cancel = _cancel;
 	}
 
 	return &this->public;
@@ -282,8 +126,8 @@ callback_job_t *callback_job_create_with_prio(callback_job_cb_t cb, void *data,
  */
 callback_job_t *callback_job_create(callback_job_cb_t cb, void *data,
 									callback_job_cleanup_t cleanup,
-									callback_job_t *parent)
+									callback_job_cancel_t cancel)
 {
-	return callback_job_create_with_prio(cb, data, cleanup, parent,
+	return callback_job_create_with_prio(cb, data, cleanup, cancel,
 										 JOB_PRIO_MEDIUM);
 }
diff --git a/src/libstrongswan/processing/jobs/callback_job.h b/src/libstrongswan/processing/jobs/callback_job.h
index 3e92b01c0..6f2e39eb8 100644
--- a/src/libstrongswan/processing/jobs/callback_job.h
+++ b/src/libstrongswan/processing/jobs/callback_job.h
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2012 Tobias Brunner
  * Copyright (C) 2007-2011 Martin Willi
  * Copyright (C) 2011 revosec AG
  * Hochschule fuer Technik Rapperswil
@@ -27,33 +28,6 @@ typedef struct callback_job_t callback_job_t;
 #include <library.h>
 #include <processing/jobs/job.h>
 
-
-typedef enum job_requeue_t job_requeue_t;
-
-/**
- * Job requeueing policy.
- *
- * The job requeueing policy defines how a job is handled when the callback
- * function returns.
- */
-enum job_requeue_t {
-
-	/**
-	 * Do not requeue job, destroy it
-	 */
-	JOB_REQUEUE_NONE,
-
-	/**
-	 * Reque the job fairly, meaning it has to requeue as any other job
-	 */
-	JOB_REQUEUE_FAIR,
-
-	/**
-	 * Reexecute the job directly, without the need of requeueing it
-	 */
-	JOB_REQUEUE_DIRECT,
-};
-
 /**
  * The callback function to use for the callback job.
  *
@@ -73,11 +47,22 @@ typedef job_requeue_t (*callback_job_cb_t)(void *data);
  * to supply to the constructor.
  *
  * @param data			param supplied to job
- * @return				requeing policy how to requeue the job
  */
 typedef void (*callback_job_cleanup_t)(void *data);
 
 /**
+ * Cancellation function to use for the callback job.
+ *
+ * Optional function to be called when a job has to be canceled.
+ *
+ * See job_t.cancel() for details on the return value.
+ *
+ * @param data			param supplied to job
+ * @return				TRUE if canceled, FALSE to explicitly cancel the thread
+ */
+typedef bool (*callback_job_cancel_t)(void *data);
+
+/**
  * Class representing an callback Job.
  *
  * This is a special job which allows a simple callback function to
@@ -91,14 +76,6 @@ struct callback_job_t {
 	 */
 	job_t job;
 
-	/**
-	 * Cancel the job's thread and wait for its termination.
-	 *
-	 * This only works reliably for jobs that always use JOB_REQUEUE_FAIR or
-	 * JOB_REQUEUE_DIRECT, otherwise the job may already be destroyed when
-	 * cancel is called.
-	 */
-	void (*cancel)(callback_job_t *this);
 };
 
 /**
@@ -106,19 +83,20 @@ struct callback_job_t {
  *
  * The cleanup function is called when the job gets destroyed to destroy
  * the associated data.
- * If parent is not NULL, the specified job gets an association. Whenever
- * the parent gets cancelled (or runs out), all of its children are cancelled,
- * too.
+ *
+ * The cancel function is optional and should only be provided if the callback
+ * function calls potentially blocking functions and/or always returns
+ * JOB_REQUEUE_DIRECT.
  *
  * @param cb				callback to call from the processor
  * @param data				user data to supply to callback
  * @param cleanup			destructor for data on destruction, or NULL
- * @param parent			parent of this job
+ * @param cancel			function to cancel the job, or NULL
  * @return					callback_job_t object
  */
 callback_job_t *callback_job_create(callback_job_cb_t cb, void *data,
 									callback_job_cleanup_t cleanup,
-									callback_job_t *parent);
+									callback_job_cancel_t cancel);
 
 /**
  * Creates a callback job, with priority.
@@ -128,12 +106,12 @@ callback_job_t *callback_job_create(callback_job_cb_t cb, void *data,
  * @param cb				callback to call from the processor
  * @param data				user data to supply to callback
  * @param cleanup			destructor for data on destruction, or NULL
- * @param parent			parent of this job
+ * @param cancel			function to cancel the job, or NULL
  * @param prio				job priority
  * @return					callback_job_t object
  */
 callback_job_t *callback_job_create_with_prio(callback_job_cb_t cb, void *data,
-					callback_job_cleanup_t cleanup, callback_job_t *parent,
-					job_priority_t prio);
+				callback_job_cleanup_t cleanup, callback_job_cancel_t cancel,
+				job_priority_t prio);
 
 #endif /** CALLBACK_JOB_H_ @}*/
diff --git a/src/libstrongswan/processing/jobs/job.h b/src/libstrongswan/processing/jobs/job.h
index d25cee03e..64454718a 100644
--- a/src/libstrongswan/processing/jobs/job.h
+++ b/src/libstrongswan/processing/jobs/job.h
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2012 Tobias Brunner
  * Copyright (C) 2005-2006 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -24,6 +25,9 @@
 
 typedef struct job_t job_t;
 typedef enum job_priority_t job_priority_t;
+typedef enum job_status_t job_status_t;
+typedef enum job_requeue_type_t job_requeue_type_t;
+typedef struct job_requeue_t job_requeue_t;
 
 #include <library.h>
 
@@ -48,18 +52,107 @@ enum job_priority_t {
 extern enum_name_t *job_priority_names;
 
 /**
+ * Job status
+ */
+enum job_status_t {
+	/** The job is queued and has not yet been executed */
+	JOB_STATUS_QUEUED = 0,
+	/** During execution */
+	JOB_STATUS_EXECUTING,
+	/** If the job got canceled */
+	JOB_STATUS_CANCELED,
+	/** The job was executed successfully */
+	JOB_STATUS_DONE,
+};
+
+/**
+ * How a job is handled after is has been executed.
+ */
+enum job_requeue_type_t {
+	/** Do not requeue job, destroy it */
+	JOB_REQUEUE_TYPE_NONE = 0,
+	/** Requeue the job fairly, i.e. it is inserted at the end of the queue */
+	JOB_REQUEUE_TYPE_FAIR,
+	/** Reexecute the job directly, without the need of requeueing it */
+	JOB_REQUEUE_TYPE_DIRECT,
+	/** Rescheduled the job via scheduler_t */
+	JOB_REQUEUE_TYPE_SCHEDULE,
+};
+
+/**
+ * Job requeueing policy.
+ *
+ * The job requeueing policy defines how a job is handled after it has been
+ * executed.
+ */
+struct job_requeue_t {
+	/** How to handle the job after executing it */
+	job_requeue_type_t type;
+	/** How to reschedule the job, if so */
+	enum {
+		JOB_SCHEDULE,
+		JOB_SCHEDULE_MS,
+		JOB_SCHEDULE_TV,
+	} schedule;
+	/** Time to reschedule the job */
+	union {
+		u_int32_t rel;
+		timeval_t abs;
+	} time;
+};
+
+/**
+ * Helper macros to easily define requeueing policies.
+ */
+#define __JOB_REQUEUE(t)			(job_requeue_t){ .type = t }
+#define JOB_REQUEUE_NONE			__JOB_REQUEUE(JOB_REQUEUE_TYPE_NONE)
+#define JOB_REQUEUE_FAIR			__JOB_REQUEUE(JOB_REQUEUE_TYPE_FAIR)
+#define JOB_REQUEUE_DIRECT			__JOB_REQUEUE(JOB_REQUEUE_TYPE_DIRECT)
+#define __JOB_RESCHEDULE(t, ...)	(job_requeue_t){ .type = JOB_REQUEUE_TYPE_SCHEDULE, .schedule = t, { __VA_ARGS__ } }
+#define JOB_RESCHEDULE(s)			__JOB_RESCHEDULE(JOB_SCHEDULE, .rel = s)
+#define JOB_RESCHEDULE_MS(ms)		__JOB_RESCHEDULE(JOB_SCHEDULE_MS, .rel = ms)
+#define JOB_RESCHEDULE_TV(tv)		__JOB_RESCHEDULE(JOB_SCHEDULE_TV, .abs = tv)
+
+/**
  * Job interface as it is stored in the job queue.
  */
 struct job_t {
 
 	/**
+	 * Status of this job, is modified exclusively by the processor/scheduler
+	 */
+	job_status_t status;
+
+	/**
 	 * Execute a job.
 	 *
 	 * The processing facility executes a job using this method. Jobs are
-	 * one-shot, they destroy themself after execution, so don't use a job
-	 * once it has been executed.
+	 * one-shot, they are destroyed after execution (depending on the return
+	 * value here), so don't use a job once it has been queued.
+	 *
+	 * @return			policy how to requeue the job
+	 */
+	job_requeue_t (*execute) (job_t *this);
+
+	/**
+	 * Cancel a job.
+	 *
+	 * Implementing this method is optional.  It allows potentially blocking
+	 * jobs to be canceled during shutdown.
+	 *
+	 * If no special action is to be taken simply return FALSE then the thread
+	 * executing the job will be canceled.  If TRUE is returned the job is
+	 * expected to return from execute() itself (i.e. the thread won't be
+	 * canceled explicitly and can still be joined later).
+	 * Jobs that return FALSE have to make sure they provide the appropriate
+	 * cancellation points.
+	 *
+	 * @note Regular jobs that do not block MUST NOT implement this method.
+	 * @note This method could be called even before execute() has been called.
+	 *
+	 * @return			FALSE to cancel the thread, TRUE if canceled otherwise
 	 */
-	void (*execute) (job_t *this);
+	bool (*cancel)(job_t *this);
 
 	/**
 	 * Get the priority of a job.
@@ -71,10 +164,12 @@ struct job_t {
 	/**
 	 * Destroy a job.
 	 *
-	 * Is only called whenever a job was not executed (e.g. due daemon shutdown).
-	 * After execution, jobs destroy themself.
+	 * Is called after a job is executed or got canceled.  It is also called
+	 * for queued jobs that were never executed.
+	 *
+	 * Use the status of a job to decide what to do during destruction.
 	 */
-	void (*destroy) (job_t *this);
+	void (*destroy)(job_t *this);
 };
 
 #endif /** JOB_H_ @}*/