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Diffstat (limited to 'libdimension/concurrency/threads.c')
| -rw-r--r-- | libdimension/concurrency/threads.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/libdimension/concurrency/threads.c b/libdimension/concurrency/threads.c new file mode 100644 index 0000000..93d2ea9 --- /dev/null +++ b/libdimension/concurrency/threads.c @@ -0,0 +1,326 @@ +/************************************************************************* + * Copyright (C) 2010-2014 Tavian Barnes <tavianator@tavianator.com> * + * * + * This file is part of The Dimension Library. * + * * + * The Dimension Library is free software; you can redistribute it and/ * + * or modify it under the terms of the GNU Lesser General Public License * + * as published by the Free Software Foundation; either version 3 of the * + * License, or (at your option) any later version. * + * * + * The Dimension Library 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 * + * Lesser General Public License for more details. * + * * + * You should have received a copy of the GNU Lesser General Public * + * License along with this program. If not, see * + * <http://www.gnu.org/licenses/>. * + *************************************************************************/ + +/** + * @file + * Background threading. + */ + +#include "internal.h" +#include "internal/concurrency.h" +#include "internal/future.h" +#include <pthread.h> + +/// The payload to pass to the pthread callback. +typedef struct dmnsn_thread_payload { + dmnsn_thread_fn *thread_fn; + void *arg; + dmnsn_future *future; +} dmnsn_thread_payload; + +/// Clean up after a thread. +static void +dmnsn_thread_cleanup(void *arg) +{ + dmnsn_thread_payload *payload = arg; + dmnsn_future *future = payload->future; + dmnsn_free(payload); + + dmnsn_future_finish(future); +} + +/// pthread callback -- call the real thread callback. +static void * +dmnsn_thread(void *arg) +{ + dmnsn_thread_payload *payload = arg; + int *ret; + + pthread_cleanup_push(dmnsn_thread_cleanup, payload); + ret = DMNSN_MALLOC(int); + *ret = payload->thread_fn(payload->arg); + pthread_cleanup_pop(true); + return ret; +} + +void +dmnsn_new_thread(dmnsn_future *future, dmnsn_thread_fn *thread_fn, void *arg) +{ + dmnsn_thread_payload *payload = DMNSN_MALLOC(dmnsn_thread_payload); + payload->thread_fn = thread_fn; + payload->arg = arg; + payload->future = future; + + if (pthread_create(&future->thread, NULL, dmnsn_thread, payload) != 0) { + dmnsn_error("Couldn't start thread."); + } +} + +/// Payload for threads executed by dmnsn_execute_concurrently(). +typedef struct dmnsn_ccthread_payload { + dmnsn_future *future; + dmnsn_ccthread_fn *ccthread_fn; + void *arg; + unsigned int thread, nthreads; + int ret; + bool running; +} dmnsn_ccthread_payload; + +static void * +dmnsn_concurrent_thread(void *ptr) +{ + dmnsn_ccthread_payload *payload = ptr; + payload->ret = payload->ccthread_fn(payload->arg, payload->thread, + payload->nthreads); + if (payload->future) { + dmnsn_future_finish_thread(payload->future); + } + return NULL; +} + +typedef struct dmnsn_ccthread_cleanup_payload { + dmnsn_future *future; + pthread_t *threads; + dmnsn_ccthread_payload *payloads; + unsigned int nthreads; +} dmnsn_ccthread_cleanup_payload; + +static void +dmnsn_ccthread_cleanup(void *ptr) +{ + dmnsn_ccthread_cleanup_payload *payload = ptr; + + for (unsigned int i = 0; i < payload->nthreads; ++i) { + if (payload->payloads[i].running) { + pthread_cancel(payload->threads[i]); + } + } + + for (unsigned int i = 0; i < payload->nthreads; ++i) { + if (payload->payloads[i].running) { + dmnsn_join_thread(payload->threads[i], NULL); + } + } + + if (payload->future) { + dmnsn_future_set_nthreads(payload->future, 1); + } +} + +int +dmnsn_execute_concurrently(dmnsn_future *future, dmnsn_ccthread_fn *ccthread_fn, + void *arg, unsigned int nthreads) +{ + dmnsn_assert(nthreads > 0, "Attempt to execute using 0 concurrent threads."); + + if (future) { + dmnsn_future_set_nthreads(future, nthreads); + } + + pthread_t threads[nthreads]; + dmnsn_ccthread_payload payloads[nthreads]; + for (unsigned int i = 0; i < nthreads; ++i) { + payloads[i].running = false; + } + + int ret = 0; + dmnsn_ccthread_cleanup_payload cleanup_payload = { + .future = future, + .threads = threads, + .payloads = payloads, + .nthreads = nthreads, + }; + pthread_cleanup_push(dmnsn_ccthread_cleanup, &cleanup_payload); + for (unsigned int i = 0; i < nthreads; ++i) { + payloads[i].future = future; + payloads[i].ccthread_fn = ccthread_fn; + payloads[i].arg = arg; + payloads[i].thread = i; + payloads[i].nthreads = nthreads; + payloads[i].ret = -1; + if (pthread_create(&threads[i], NULL, dmnsn_concurrent_thread, + &payloads[i]) != 0) + { + dmnsn_error("Couldn't start worker thread."); + } + payloads[i].running = true; + } + + for (unsigned int i = 0; i < nthreads; ++i) { + dmnsn_join_thread(threads[i], NULL); + payloads[i].running = false; + if (payloads[i].ret != 0) { + ret = payloads[i].ret; + } + } + pthread_cleanup_pop(false); + + if (future) { + dmnsn_future_set_nthreads(future, 1); + } + + return ret; +} + +// pthread wrappers + +void +dmnsn_initialize_mutex(pthread_mutex_t *mutex) +{ + if (pthread_mutex_init(mutex, NULL) != 0) { + dmnsn_error("Couldn't initialize mutex."); + } +} + +void +dmnsn_lock_mutex_impl(pthread_mutex_t *mutex) +{ + if (pthread_mutex_lock(mutex) != 0) { + dmnsn_error("Couldn't lock mutex."); + } +} + +void +dmnsn_unlock_mutex_impl(void *mutex) +{ + if (pthread_mutex_unlock(mutex) != 0) { + dmnsn_error("Couldn't unlock mutex."); + } +} + +void +dmnsn_destroy_mutex(pthread_mutex_t *mutex) +{ + if (pthread_mutex_destroy(mutex) != 0) { + dmnsn_warning("Couldn't destroy mutex."); + } +} + +void +dmnsn_initialize_rwlock(pthread_rwlock_t *rwlock) +{ + if (pthread_rwlock_init(rwlock, NULL) != 0) { + dmnsn_error("Couldn't initialize read-write lock."); + } +} + +void +dmnsn_read_lock_impl(pthread_rwlock_t *rwlock) +{ + if (pthread_rwlock_rdlock(rwlock) != 0) { + dmnsn_error("Couldn't acquire read lock."); + } +} + +void +dmnsn_write_lock_impl(pthread_rwlock_t *rwlock) +{ + if (pthread_rwlock_wrlock(rwlock) != 0) { + dmnsn_error("Couldn't acquire write lock."); + } +} + +void +dmnsn_unlock_rwlock_impl(pthread_rwlock_t *rwlock) +{ + if (pthread_rwlock_unlock(rwlock) != 0) { + dmnsn_error("Couldn't unlock read-write lock."); + } +} + +void +dmnsn_destroy_rwlock(pthread_rwlock_t *rwlock) +{ + if (pthread_rwlock_destroy(rwlock) != 0) { + dmnsn_warning("Couldn't destroy read-write lock."); + } +} + +void +dmnsn_initialize_cond(pthread_cond_t *cond) +{ + if (pthread_cond_init(cond, NULL) != 0) { + dmnsn_error("Couldn't initialize condition variable."); + } +} + +void +dmnsn_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex) +{ + if (pthread_cond_wait(cond, mutex) != 0) { + dmnsn_error("Couldn't wait on condition variable."); + } +} + +void +dmnsn_cond_broadcast(pthread_cond_t *cond) +{ + if (pthread_cond_broadcast(cond) != 0) { + dmnsn_error("Couldn't signal condition variable."); + } +} + +void +dmnsn_destroy_cond(pthread_cond_t *cond) +{ + if (pthread_cond_destroy(cond) != 0) { + dmnsn_warning("Couldn't destroy condition variable."); + } +} + +void +dmnsn_once(pthread_once_t *once, dmnsn_once_fn *once_fn) +{ + if (pthread_once(once, once_fn) != 0) { + dmnsn_error("Couldn't call one-shot function."); + } +} + +void +dmnsn_key_create(pthread_key_t *key, dmnsn_callback_fn *destructor) +{ + if (pthread_key_create(key, destructor) != 0) { + dmnsn_error("Couldn't initialize thread-specific pointer."); + } +} + +void +dmnsn_setspecific(pthread_key_t key, const void *value) +{ + if (pthread_setspecific(key, value) != 0) { + dmnsn_error("Couldn't set thread-specific pointer."); + } +} + +void +dmnsn_key_delete(pthread_key_t key) +{ + if (pthread_key_delete(key) != 0) { + dmnsn_warning("Couldn't destroy thread-specific pointer."); + } +} + +void +dmnsn_join_thread(pthread_t thread, void **retval) +{ + if (pthread_join(thread, retval) != 0) { + dmnsn_error("Couldn't join thread."); + } +} |