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Diffstat (limited to 'include/c11/threads_posix.h')
| -rw-r--r-- | include/c11/threads_posix.h | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/include/c11/threads_posix.h b/include/c11/threads_posix.h new file mode 100644 index 0000000000..463c93f45c --- /dev/null +++ b/include/c11/threads_posix.h @@ -0,0 +1,346 @@ +/* + * C11 <threads.h> emulation library + * + * (C) Copyright yohhoy 2012. + * Distributed under the Boost Software License, Version 1.0. + * (See copy at http://www.boost.org/LICENSE_1_0.txt) + */ +#include <stdlib.h> +#include <assert.h> +#include <limits.h> +#include <errno.h> +#include <unistd.h> +#include <sched.h> +#include <stdint.h> /* for intptr_t */ + +/* +Configuration macro: + + EMULATED_THREADS_USE_NATIVE_TIMEDLOCK + Use pthread_mutex_timedlock() for `mtx_timedlock()' + Otherwise use mtx_trylock() + *busy loop* emulation. +*/ +#if !defined(__CYGWIN__) +#define EMULATED_THREADS_USE_NATIVE_TIMEDLOCK +#endif + + +#include <pthread.h> + +/*---------------------------- macros ----------------------------*/ +#define ONCE_FLAG_INIT PTHREAD_ONCE_INIT +#ifdef INIT_ONCE_STATIC_INIT +#define TSS_DTOR_ITERATIONS PTHREAD_DESTRUCTOR_ITERATIONS +#else +#define TSS_DTOR_ITERATIONS 1 // assume TSS dtor MAY be called at least once. +#endif + +// FIXME: temporary non-standard hack to ease transition +#define _MTX_INITIALIZER_NP PTHREAD_MUTEX_INITIALIZER + +/*---------------------------- types ----------------------------*/ +typedef pthread_cond_t cnd_t; +typedef pthread_t thrd_t; +typedef pthread_key_t tss_t; +typedef pthread_mutex_t mtx_t; +typedef pthread_once_t once_flag; + + +/* +Implementation limits: + - Conditionally emulation for "mutex with timeout" + (see EMULATED_THREADS_USE_NATIVE_TIMEDLOCK macro) +*/ +struct impl_thrd_param { + thrd_start_t func; + void *arg; +}; + +static inline void * +impl_thrd_routine(void *p) +{ + struct impl_thrd_param pack = *((struct impl_thrd_param *)p); + free(p); + return (void*)(intptr_t)pack.func(pack.arg); +} + + +/*--------------- 7.25.2 Initialization functions ---------------*/ +// 7.25.2.1 +static inline void +call_once(once_flag *flag, void (*func)(void)) +{ + pthread_once(flag, func); +} + + +/*------------- 7.25.3 Condition variable functions -------------*/ +// 7.25.3.1 +static inline int +cnd_broadcast(cnd_t *cond) +{ + if (!cond) return thrd_error; + pthread_cond_broadcast(cond); + return thrd_success; +} + +// 7.25.3.2 +static inline void +cnd_destroy(cnd_t *cond) +{ + assert(cond); + pthread_cond_destroy(cond); +} + +// 7.25.3.3 +static inline int +cnd_init(cnd_t *cond) +{ + if (!cond) return thrd_error; + pthread_cond_init(cond, NULL); + return thrd_success; +} + +// 7.25.3.4 +static inline int +cnd_signal(cnd_t *cond) +{ + if (!cond) return thrd_error; + pthread_cond_signal(cond); + return thrd_success; +} + +// 7.25.3.5 +static inline int +cnd_timedwait(cnd_t *cond, mtx_t *mtx, const xtime *xt) +{ + struct timespec abs_time; + int rt; + if (!cond || !mtx || !xt) return thrd_error; + rt = pthread_cond_timedwait(cond, mtx, &abs_time); + if (rt == ETIMEDOUT) + return thrd_busy; + return (rt == 0) ? thrd_success : thrd_error; +} + +// 7.25.3.6 +static inline int +cnd_wait(cnd_t *cond, mtx_t *mtx) +{ + if (!cond || !mtx) return thrd_error; + pthread_cond_wait(cond, mtx); + return thrd_success; +} + + +/*-------------------- 7.25.4 Mutex functions --------------------*/ +// 7.25.4.1 +static inline void +mtx_destroy(mtx_t *mtx) +{ + assert(mtx); + pthread_mutex_destroy(mtx); +} + +// 7.25.4.2 +static inline int +mtx_init(mtx_t *mtx, int type) +{ + pthread_mutexattr_t attr; + if (!mtx) return thrd_error; + if (type != mtx_plain && type != mtx_timed && type != mtx_try + && type != (mtx_plain|mtx_recursive) + && type != (mtx_timed|mtx_recursive) + && type != (mtx_try|mtx_recursive)) + return thrd_error; + pthread_mutexattr_init(&attr); + if ((type & mtx_recursive) != 0) { +#if defined(__linux__) || defined(__linux) + pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE_NP); +#else + pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); +#endif + } + pthread_mutex_init(mtx, &attr); + pthread_mutexattr_destroy(&attr); + return thrd_success; +} + +// 7.25.4.3 +static inline int +mtx_lock(mtx_t *mtx) +{ + if (!mtx) return thrd_error; + pthread_mutex_lock(mtx); + return thrd_success; +} + +// 7.25.4.4 +static inline int +mtx_timedlock(mtx_t *mtx, const xtime *xt) +{ + if (!mtx || !xt) return thrd_error; + { +#ifdef EMULATED_THREADS_USE_NATIVE_TIMEDLOCK + struct timespec ts; + int rt; + ts.tv_sec = xt->sec; + ts.tv_nsec = xt->nsec; + rt = pthread_mutex_timedlock(mtx, &ts); + if (rt == 0) + return thrd_success; + return (rt == ETIMEDOUT) ? thrd_busy : thrd_error; +#else + time_t expire = time(NULL); + expire += xt->sec; + while (mtx_trylock(mtx) != thrd_success) { + time_t now = time(NULL); + if (expire < now) + return thrd_busy; + // busy loop! + thrd_yield(); + } + return thrd_success; +#endif + } +} + +// 7.25.4.5 +static inline int +mtx_trylock(mtx_t *mtx) +{ + if (!mtx) return thrd_error; + return (pthread_mutex_trylock(mtx) == 0) ? thrd_success : thrd_busy; +} + +// 7.25.4.6 +static inline int +mtx_unlock(mtx_t *mtx) +{ + if (!mtx) return thrd_error; + pthread_mutex_unlock(mtx); + return thrd_success; +} + + +/*------------------- 7.25.5 Thread functions -------------------*/ +// 7.25.5.1 +static inline int +thrd_create(thrd_t *thr, thrd_start_t func, void *arg) +{ + struct impl_thrd_param *pack; + if (!thr) return thrd_error; + pack = (struct impl_thrd_param *)malloc(sizeof(struct impl_thrd_param)); + if (!pack) return thrd_nomem; + pack->func = func; + pack->arg = arg; + if (pthread_create(thr, NULL, impl_thrd_routine, pack) != 0) { + free(pack); + return thrd_error; + } + return thrd_success; +} + +// 7.25.5.2 +static inline thrd_t +thrd_current(void) +{ + return pthread_self(); +} + +// 7.25.5.3 +static inline int +thrd_detach(thrd_t thr) +{ + return (pthread_detach(thr) == 0) ? thrd_success : thrd_error; +} + +// 7.25.5.4 +static inline int +thrd_equal(thrd_t thr0, thrd_t thr1) +{ + return pthread_equal(thr0, thr1); +} + +// 7.25.5.5 +static inline void +thrd_exit(int res) +{ + pthread_exit((void*)(intptr_t)res); +} + +// 7.25.5.6 +static inline int +thrd_join(thrd_t thr, int *res) +{ + void *code; + if (pthread_join(thr, &code) != 0) + return thrd_error; + if (res) + *res = (int)(intptr_t)code; + return thrd_success; +} + +// 7.25.5.7 +static inline void +thrd_sleep(const xtime *xt) +{ + struct timespec req; + assert(xt); + req.tv_sec = xt->sec; + req.tv_nsec = xt->nsec; + nanosleep(&req, NULL); +} + +// 7.25.5.8 +static inline void +thrd_yield(void) +{ + sched_yield(); +} + + +/*----------- 7.25.6 Thread-specific storage functions -----------*/ +// 7.25.6.1 +static inline int +tss_create(tss_t *key, tss_dtor_t dtor) +{ + if (!key) return thrd_error; + return (pthread_key_create(key, dtor) == 0) ? thrd_success : thrd_error; +} + +// 7.25.6.2 +static inline void +tss_delete(tss_t key) +{ + pthread_key_delete(key); +} + +// 7.25.6.3 +static inline void * +tss_get(tss_t key) +{ + return pthread_getspecific(key); +} + +// 7.25.6.4 +static inline int +tss_set(tss_t key, void *val) +{ + return (pthread_setspecific(key, val) == 0) ? thrd_success : thrd_error; +} + + +/*-------------------- 7.25.7 Time functions --------------------*/ +// 7.25.6.1 +static inline int +xtime_get(xtime *xt, int base) +{ + if (!xt) return 0; + if (base == TIME_UTC) { + xt->sec = time(NULL); + xt->nsec = 0; + return base; + } + return 0; +} |