summaryrefslogtreecommitdiffstats
path: root/lib/pthreadpool/pthreadpool.h
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--lib/pthreadpool/pthreadpool.h158
1 files changed, 158 insertions, 0 deletions
diff --git a/lib/pthreadpool/pthreadpool.h b/lib/pthreadpool/pthreadpool.h
new file mode 100644
index 0000000..b473358
--- /dev/null
+++ b/lib/pthreadpool/pthreadpool.h
@@ -0,0 +1,158 @@
+/*
+ * Unix SMB/CIFS implementation.
+ * threadpool implementation based on pthreads
+ * Copyright (C) Volker Lendecke 2009,2011
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __PTHREADPOOL_H__
+#define __PTHREADPOOL_H__
+
+struct pthreadpool;
+
+/**
+ * @defgroup pthreadpool The pthreadpool API
+ *
+ * This API provides a way to run threadsafe functions in a helper
+ * thread. It is initially intended to run getaddrinfo asynchronously.
+ */
+
+
+/**
+ * @brief Create a pthreadpool
+ *
+ * A struct pthreadpool is the basis for for running threads in the
+ * background.
+ *
+ * @param[in] max_threads Maximum parallelism in this pool
+ * @param[out] presult Pointer to the threadpool returned
+ * @return success: 0, failure: errno
+ *
+ * max_threads=0 means unlimited parallelism. The caller has to take
+ * care to not overload the system.
+ */
+int pthreadpool_init(unsigned max_threads, struct pthreadpool **presult,
+ int (*signal_fn)(int jobid,
+ void (*job_fn)(void *private_data),
+ void *job_fn_private_data,
+ void *private_data),
+ void *signal_fn_private_data);
+
+/**
+ * @brief Get the max threads value of pthreadpool
+ *
+ * @note This can be 0 for strict sync processing.
+ *
+ * @param[in] pool The pool
+ * @return number of possible threads
+ */
+size_t pthreadpool_max_threads(struct pthreadpool *pool);
+
+/**
+ * @brief The number of queued jobs of pthreadpool
+ *
+ * This is the number of jobs added by pthreadpool_add_job(),
+ * which are not yet processed by a thread.
+ *
+ * @param[in] pool The pool
+ * @return The number of jobs
+ */
+size_t pthreadpool_queued_jobs(struct pthreadpool *pool);
+
+/**
+ * @brief Stop a pthreadpool
+ *
+ * Stop a pthreadpool. If jobs are submitted, but not yet active in
+ * a thread, they won't get executed. If a job has already been
+ * submitted to a thread, the job function will continue running, and
+ * the signal function might still be called.
+ *
+ * This allows a multi step shutdown using pthreadpool_stop(),
+ * pthreadpool_cancel_job() and pthreadpool_destroy().
+ *
+ * @param[in] pool The pool to stop
+ * @return success: 0, failure: errno
+ *
+ * @see pthreadpool_cancel_job()
+ * @see pthreadpool_destroy()
+ */
+int pthreadpool_stop(struct pthreadpool *pool);
+
+/**
+ * @brief Destroy a pthreadpool
+ *
+ * This basically implies pthreadpool_stop() if the pool
+ * isn't already stopped.
+ *
+ * Destroy a pthreadpool. If jobs are submitted, but not yet active in
+ * a thread, they won't get executed. If a job has already been
+ * submitted to a thread, the job function will continue running, and
+ * the signal function might still be called. The caller of
+ * pthreadpool_init must make sure the required resources are still
+ * around when the pool is destroyed with pending jobs. The last
+ * thread to exit will finally free() the pool memory.
+ *
+ * @param[in] pool The pool to destroy
+ * @return success: 0, failure: errno
+ *
+ * @see pthreadpool_stop()
+ */
+int pthreadpool_destroy(struct pthreadpool *pool);
+
+/**
+ * @brief Add a job to a pthreadpool
+ *
+ * This adds a job to a pthreadpool. The job can be identified by
+ * job_id. This integer will be passed to signal_fn() when the
+ * job is completed.
+ *
+ * @param[in] pool The pool to run the job on
+ * @param[in] job_id A custom identifier
+ * @param[in] fn The function to run asynchronously
+ * @param[in] private_data Pointer passed to fn
+ * @return success: 0, failure: errno
+ */
+int pthreadpool_add_job(struct pthreadpool *pool, int job_id,
+ void (*fn)(void *private_data), void *private_data);
+
+/**
+ * @brief Try to cancel a job in a pthreadpool
+ *
+ * This tries to cancel a job in a pthreadpool. The same
+ * arguments, which were given to pthreadpool_add_job()
+ * needs to be passed.
+ *
+ * The combination of id, fn, private_data might not be unique.
+ * So the function tries to cancel as much matching jobs as possible.
+ * Note once a job is scheduled in a thread it's to late to
+ * cancel it.
+ *
+ * Canceled jobs that weren't started yet won't be reported via a
+ * pool's signal_fn.
+ *
+ * @param[in] pool The pool to run the job on
+ * @param[in] job_id A custom identifier
+ * @param[in] fn The function to run asynchronously
+ * @param[in] private_data Pointer passed to fn
+ * @return The number of canceled jobs
+ *
+ * @see pthreadpool_add_job()
+ * @see pthreadpool_stop()
+ * @see pthreadpool_destroy()
+ */
+size_t pthreadpool_cancel_job(struct pthreadpool *pool, int job_id,
+ void (*fn)(void *private_data), void *private_data);
+
+#endif