mod_url progress

[assman] / src / tpool.h

diff --git a/src/tpool.h b/src/tpool.h
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+++ b/src/tpool.h
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+/* worker thread pool based on POSIX threads
+ * author: John Tsiombikas <nuclear@member.fsf.org>
+ * This code is public domain.
+ */
+#ifndef ASSMAN_THREADPOOL_H_
+#define ASSMAN_THREADPOOL_H_
+
+struct thread_pool;
+
+/* type of the function accepted as work or completion callback */
+typedef void (*tpool_callback)(void*);
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* if num_threads == 0, auto-detect how many threads to spawn */
+struct thread_pool *ass_tpool_create(int num_threads);
+void ass_tpool_destroy(struct thread_pool *tpool);
+
+/* optional reference counting interface for thread pool sharing */
+int ass_tpool_addref(struct thread_pool *tpool);
+int ass_tpool_release(struct thread_pool *tpool);      /* will ass_tpool_destroy on nref 0 */
+
+/* if begin_batch is called before an enqueue, the worker threads will not be
+ * signalled to start working until end_batch is called.
+ */
+void ass_tpool_begin_batch(struct thread_pool *tpool);
+void ass_tpool_end_batch(struct thread_pool *tpool);
+
+/* if enqueue is called without calling begin_batch first, it will immediately
+ * wake up the worker threads to start working on the enqueued item
+ */
+int ass_tpool_enqueue(struct thread_pool *tpool, void *data,
+               tpool_callback work_func, tpool_callback done_func);
+/* clear the work queue. does not cancel any currently running jobs */
+void ass_tpool_clear(struct thread_pool *tpool);
+
+/* returns the number of queued work items */
+int ass_tpool_queued_jobs(struct thread_pool *tpool);
+/* returns the number of active (working) threads */
+int ass_tpool_active_jobs(struct thread_pool *tpool);
+/* returns the number of pending jobs, both in queue and active */
+int ass_tpool_pending_jobs(struct thread_pool *tpool);
+
+/* wait for all pending jobs to be completed */
+void ass_tpool_wait(struct thread_pool *tpool);
+/* wait until the pending jobs are down to the target specified
+ * for example, to wait until a single job has been completed:
+ *   ass_tpool_wait_pending(tpool, ass_tpool_pending_jobs(tpool) - 1);
+ * this interface is slightly awkward to avoid race conditions. */
+void ass_tpool_wait_pending(struct thread_pool *tpool, int pending_target);
+/* wait for all pending jobs to be completed for up to "timeout" milliseconds */
+long ass_tpool_timedwait(struct thread_pool *tpool, long timeout);
+
+/* return a file descriptor which can be used to wait for pending job
+ * completion events. A single char is written every time a job completes.
+ * You should empty the pipe every time you receive such an event.
+ *
+ * This is a UNIX-specific call. On windows it does nothing.
+ */
+int ass_tpool_get_wait_fd(struct thread_pool *tpool);
+
+/* return an auto-resetting Event HANDLE which can be used to wait for
+ * pending job completion events.
+ *
+ * This is a Win32-specific call. On UNIX it does nothing.
+ */
+void *ass_tpool_get_wait_handle(struct thread_pool *tpool);
+
+/* When called by a work/done callback, it returns the thread number executing
+ * it. From the main thread it returns -1.
+ */
+int ass_tpool_thread_id(struct thread_pool *tpool);
+
+/* returns the number of processors on the system.
+ * individual cores in multi-core processors are counted as processors.
+ */
+int ass_tpool_num_processors(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* ASSMAN_THREADPOOL_H_ */