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Diffstat (limited to 'include/c11/threads_win32.h')
| -rw-r--r-- | include/c11/threads_win32.h | 588 |
1 files changed, 588 insertions, 0 deletions
diff --git a/include/c11/threads_win32.h b/include/c11/threads_win32.h new file mode 100644 index 0000000..5a63e90 --- /dev/null +++ b/include/c11/threads_win32.h @@ -0,0 +1,588 @@ +/* + * 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 <assert.h> +#include <limits.h> +#include <errno.h> +#include <process.h> // MSVCRT + +/* +Configuration macro: + + EMULATED_THREADS_USE_NATIVE_CALL_ONCE + Use native WindowsAPI one-time initialization function. + (requires WinVista or later) + Otherwise emulate by mtx_trylock() + *busy loop* for WinXP. + + EMULATED_THREADS_USE_NATIVE_CV + Use native WindowsAPI condition variable object. + (requires WinVista or later) + Otherwise use emulated implementation for WinXP. + + EMULATED_THREADS_TSS_DTOR_SLOTNUM + Max registerable TSS dtor number. +*/ + +// XXX: Retain XP compatability +#if 0 +#if _WIN32_WINNT >= 0x0600 +// Prefer native WindowsAPI on newer environment. +#if !defined(__MINGW32__) +#define EMULATED_THREADS_USE_NATIVE_CALL_ONCE +#endif +#define EMULATED_THREADS_USE_NATIVE_CV +#endif +#endif +#define EMULATED_THREADS_TSS_DTOR_SLOTNUM 64 // see TLS_MINIMUM_AVAILABLE + + +#include <windows.h> + +// check configuration +#if defined(EMULATED_THREADS_USE_NATIVE_CALL_ONCE) && (_WIN32_WINNT < 0x0600) +#error EMULATED_THREADS_USE_NATIVE_CALL_ONCE requires _WIN32_WINNT>=0x0600 +#endif + +#if defined(EMULATED_THREADS_USE_NATIVE_CV) && (_WIN32_WINNT < 0x0600) +#error EMULATED_THREADS_USE_NATIVE_CV requires _WIN32_WINNT>=0x0600 +#endif + + +/*---------------------------- macros ----------------------------*/ +#ifdef EMULATED_THREADS_USE_NATIVE_CALL_ONCE +#define ONCE_FLAG_INIT INIT_ONCE_STATIC_INIT +#else +#define ONCE_FLAG_INIT {0} +#endif +#define TSS_DTOR_ITERATIONS 1 + +// FIXME: temporary non-standard hack to ease transition +#define _MTX_INITIALIZER_NP {(PCRITICAL_SECTION_DEBUG)-1, -1, 0, 0, 0, 0} + +/*---------------------------- types ----------------------------*/ +typedef struct cnd_t { +#ifdef EMULATED_THREADS_USE_NATIVE_CV + CONDITION_VARIABLE condvar; +#else + int blocked; + int gone; + int to_unblock; + HANDLE sem_queue; + HANDLE sem_gate; + CRITICAL_SECTION monitor; +#endif +} cnd_t; + +typedef HANDLE thrd_t; + +typedef DWORD tss_t; + +typedef CRITICAL_SECTION mtx_t; + +#ifdef EMULATED_THREADS_USE_NATIVE_CALL_ONCE +typedef INIT_ONCE once_flag; +#else +typedef struct once_flag_t { + volatile LONG status; +} once_flag; +#endif + + +static inline void * tss_get(tss_t key); +static inline void thrd_yield(void); +static inline int mtx_trylock(mtx_t *mtx); +static inline int mtx_lock(mtx_t *mtx); +static inline int mtx_unlock(mtx_t *mtx); + +/* +Implementation limits: + - Conditionally emulation for "Initialization functions" + (see EMULATED_THREADS_USE_NATIVE_CALL_ONCE macro) + - Emulated `mtx_timelock()' with mtx_trylock() + *busy loop* +*/ +static void impl_tss_dtor_invoke(void); // forward decl. + +struct impl_thrd_param { + thrd_start_t func; + void *arg; +}; + +static unsigned __stdcall impl_thrd_routine(void *p) +{ + struct impl_thrd_param pack; + int code; + memcpy(&pack, p, sizeof(struct impl_thrd_param)); + free(p); + code = pack.func(pack.arg); + impl_tss_dtor_invoke(); + return (unsigned)code; +} + +static DWORD impl_xtime2msec(const xtime *xt) +{ + return (DWORD)((xt->sec * 1000u) + (xt->nsec / 1000)); +} + +#ifdef EMULATED_THREADS_USE_NATIVE_CALL_ONCE +struct impl_call_once_param { void (*func)(void); }; +static BOOL CALLBACK impl_call_once_callback(PINIT_ONCE InitOnce, PVOID Parameter, PVOID *Context) +{ + struct impl_call_once_param *param = (struct impl_call_once_param*)Parameter; + (param->func)(); + ((void)InitOnce); ((void)Context); // suppress warning + return TRUE; +} +#endif // ifdef EMULATED_THREADS_USE_NATIVE_CALL_ONCE + +#ifndef EMULATED_THREADS_USE_NATIVE_CV +/* +Note: + The implementation of condition variable is ported from Boost.Interprocess + See http://www.boost.org/boost/interprocess/sync/windows/condition.hpp +*/ +static void impl_cond_do_signal(cnd_t *cond, int broadcast) +{ + int nsignal = 0; + + EnterCriticalSection(&cond->monitor); + if (cond->to_unblock != 0) { + if (cond->blocked == 0) { + LeaveCriticalSection(&cond->monitor); + return; + } + if (broadcast) { + cond->to_unblock += nsignal = cond->blocked; + cond->blocked = 0; + } else { + nsignal = 1; + cond->to_unblock++; + cond->blocked--; + } + } else if (cond->blocked > cond->gone) { + WaitForSingleObject(cond->sem_gate, INFINITE); + if (cond->gone != 0) { + cond->blocked -= cond->gone; + cond->gone = 0; + } + if (broadcast) { + nsignal = cond->to_unblock = cond->blocked; + cond->blocked = 0; + } else { + nsignal = cond->to_unblock = 1; + cond->blocked--; + } + } + LeaveCriticalSection(&cond->monitor); + + if (0 < nsignal) + ReleaseSemaphore(cond->sem_queue, nsignal, NULL); +} + +static int impl_cond_do_wait(cnd_t *cond, mtx_t *mtx, const xtime *xt) +{ + int nleft = 0; + int ngone = 0; + int timeout = 0; + DWORD w; + + WaitForSingleObject(cond->sem_gate, INFINITE); + cond->blocked++; + ReleaseSemaphore(cond->sem_gate, 1, NULL); + + mtx_unlock(mtx); + + w = WaitForSingleObject(cond->sem_queue, xt ? impl_xtime2msec(xt) : INFINITE); + timeout = (w == WAIT_TIMEOUT); + + EnterCriticalSection(&cond->monitor); + if ((nleft = cond->to_unblock) != 0) { + if (timeout) { + if (cond->blocked != 0) { + cond->blocked--; + } else { + cond->gone++; + } + } + if (--cond->to_unblock == 0) { + if (cond->blocked != 0) { + ReleaseSemaphore(cond->sem_gate, 1, NULL); + nleft = 0; + } + else if ((ngone = cond->gone) != 0) { + cond->gone = 0; + } + } + } else if (++cond->gone == INT_MAX/2) { + WaitForSingleObject(cond->sem_gate, INFINITE); + cond->blocked -= cond->gone; + ReleaseSemaphore(cond->sem_gate, 1, NULL); + cond->gone = 0; + } + LeaveCriticalSection(&cond->monitor); + + if (nleft == 1) { + while (ngone--) + WaitForSingleObject(cond->sem_queue, INFINITE); + ReleaseSemaphore(cond->sem_gate, 1, NULL); + } + + mtx_lock(mtx); + return timeout ? thrd_busy : thrd_success; +} +#endif // ifndef EMULATED_THREADS_USE_NATIVE_CV + +static struct impl_tss_dtor_entry { + tss_t key; + tss_dtor_t dtor; +} impl_tss_dtor_tbl[EMULATED_THREADS_TSS_DTOR_SLOTNUM]; + +static int impl_tss_dtor_register(tss_t key, tss_dtor_t dtor) +{ + int i; + for (i = 0; i < EMULATED_THREADS_TSS_DTOR_SLOTNUM; i++) { + if (!impl_tss_dtor_tbl[i].dtor) + break; + } + if (i == EMULATED_THREADS_TSS_DTOR_SLOTNUM) + return 1; + impl_tss_dtor_tbl[i].key = key; + impl_tss_dtor_tbl[i].dtor = dtor; + return 0; +} + +static void impl_tss_dtor_invoke() +{ + int i; + for (i = 0; i < EMULATED_THREADS_TSS_DTOR_SLOTNUM; i++) { + if (impl_tss_dtor_tbl[i].dtor) { + void* val = tss_get(impl_tss_dtor_tbl[i].key); + if (val) + (impl_tss_dtor_tbl[i].dtor)(val); + } + } +} + + +/*--------------- 7.25.2 Initialization functions ---------------*/ +// 7.25.2.1 +static inline void +call_once(once_flag *flag, void (*func)(void)) +{ + assert(!flag && !func); +#ifdef EMULATED_THREADS_USE_NATIVE_CALL_ONCE + { + struct impl_call_once_param param; + param.func = func; + InitOnceExecuteOnce(flag, impl_call_once_callback, (PVOID)¶m, NULL); + } +#else + if (InterlockedCompareExchange(&flag->status, 1, 0) == 0) { + (func)(); + InterlockedExchange(&flag->status, 2); + } else { + while (flag->status == 1) { + // busy loop! + thrd_yield(); + } + } +#endif +} + + +/*------------- 7.25.3 Condition variable functions -------------*/ +// 7.25.3.1 +static inline int +cnd_broadcast(cnd_t *cond) +{ + if (!cond) return thrd_error; +#ifdef EMULATED_THREADS_USE_NATIVE_CV + WakeAllConditionVariable(&cond->condvar); +#else + impl_cond_do_signal(cond, 1); +#endif + return thrd_success; +} + +// 7.25.3.2 +static inline void +cnd_destroy(cnd_t *cond) +{ + assert(cond); +#ifdef EMULATED_THREADS_USE_NATIVE_CV + // do nothing +#else + CloseHandle(cond->sem_queue); + CloseHandle(cond->sem_gate); + DeleteCriticalSection(&cond->monitor); +#endif +} + +// 7.25.3.3 +static inline int +cnd_init(cnd_t *cond) +{ + if (!cond) return thrd_error; +#ifdef EMULATED_THREADS_USE_NATIVE_CV + InitializeConditionVariable(&cond->condvar); +#else + cond->blocked = 0; + cond->gone = 0; + cond->to_unblock = 0; + cond->sem_queue = CreateSemaphore(NULL, 0, LONG_MAX, NULL); + cond->sem_gate = CreateSemaphore(NULL, 1, 1, NULL); + InitializeCriticalSection(&cond->monitor); +#endif + return thrd_success; +} + +// 7.25.3.4 +static inline int +cnd_signal(cnd_t *cond) +{ + if (!cond) return thrd_error; +#ifdef EMULATED_THREADS_USE_NATIVE_CV + WakeConditionVariable(&cond->condvar); +#else + impl_cond_do_signal(cond, 0); +#endif + return thrd_success; +} + +// 7.25.3.5 +static inline int +cnd_timedwait(cnd_t *cond, mtx_t *mtx, const xtime *xt) +{ + if (!cond || !mtx || !xt) return thrd_error; +#ifdef EMULATED_THREADS_USE_NATIVE_CV + if (SleepConditionVariableCS(&cond->condvar, mtx, impl_xtime2msec(xt))) + return thrd_success; + return (GetLastError() == ERROR_TIMEOUT) ? thrd_busy : thrd_error; +#else + return impl_cond_do_wait(cond, mtx, xt); +#endif +} + +// 7.25.3.6 +static inline int +cnd_wait(cnd_t *cond, mtx_t *mtx) +{ + if (!cond || !mtx) return thrd_error; +#ifdef EMULATED_THREADS_USE_NATIVE_CV + SleepConditionVariableCS(&cond->condvar, mtx, INFINITE); +#else + impl_cond_do_wait(cond, mtx, NULL); +#endif + return thrd_success; +} + + +/*-------------------- 7.25.4 Mutex functions --------------------*/ +// 7.25.4.1 +static inline void +mtx_destroy(mtx_t *mtx) +{ + assert(mtx); + DeleteCriticalSection(mtx); +} + +// 7.25.4.2 +static inline int +mtx_init(mtx_t *mtx, int type) +{ + 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; + InitializeCriticalSection(mtx); + return thrd_success; +} + +// 7.25.4.3 +static inline int +mtx_lock(mtx_t *mtx) +{ + if (!mtx) return thrd_error; + EnterCriticalSection(mtx); + return thrd_success; +} + +// 7.25.4.4 +static inline int +mtx_timedlock(mtx_t *mtx, const xtime *xt) +{ + time_t expire, now; + if (!mtx || !xt) return thrd_error; + expire = time(NULL); + expire += xt->sec; + while (mtx_trylock(mtx) != thrd_success) { + now = time(NULL); + if (expire < now) + return thrd_busy; + // busy loop! + thrd_yield(); + } + return thrd_success; +} + +// 7.25.4.5 +static inline int +mtx_trylock(mtx_t *mtx) +{ + if (!mtx) return thrd_error; + return TryEnterCriticalSection(mtx) ? thrd_success : thrd_busy; +} + +// 7.25.4.6 +static inline int +mtx_unlock(mtx_t *mtx) +{ + if (!mtx) return thrd_error; + LeaveCriticalSection(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; + uintptr_t handle; + 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; + handle = _beginthreadex(NULL, 0, impl_thrd_routine, pack, 0, NULL); + if (handle == 0) { + if (errno == EAGAIN || errno == EACCES) + return thrd_nomem; + return thrd_error; + } + *thr = (thrd_t)handle; + return thrd_success; +} + +// 7.25.5.2 +static inline thrd_t +thrd_current(void) +{ + return GetCurrentThread(); +} + +// 7.25.5.3 +static inline int +thrd_detach(thrd_t thr) +{ + CloseHandle(thr); + return thrd_success; +} + +// 7.25.5.4 +static inline int +thrd_equal(thrd_t thr0, thrd_t thr1) +{ + return (thr0 == thr1); +} + +// 7.25.5.5 +static inline void +thrd_exit(int res) +{ + impl_tss_dtor_invoke(); + _endthreadex((unsigned)res); +} + +// 7.25.5.6 +static inline int +thrd_join(thrd_t thr, int *res) +{ + DWORD w, code; + w = WaitForSingleObject(thr, INFINITE); + if (w != WAIT_OBJECT_0) + return thrd_error; + if (res) { + if (!GetExitCodeThread(thr, &code)) { + CloseHandle(thr); + return thrd_error; + } + *res = (int)code; + } + CloseHandle(thr); + return thrd_success; +} + +// 7.25.5.7 +static inline void +thrd_sleep(const xtime *xt) +{ + assert(xt); + Sleep(impl_xtime2msec(xt)); +} + +// 7.25.5.8 +static inline void +thrd_yield(void) +{ + SwitchToThread(); +} + + +/*----------- 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; + *key = TlsAlloc(); + if (dtor) { + if (impl_tss_dtor_register(*key, dtor)) { + TlsFree(*key); + return thrd_error; + } + } + return (*key != 0xFFFFFFFF) ? thrd_success : thrd_error; +} + +// 7.25.6.2 +static inline void +tss_delete(tss_t key) +{ + TlsFree(key); +} + +// 7.25.6.3 +static inline void * +tss_get(tss_t key) +{ + return TlsGetValue(key); +} + +// 7.25.6.4 +static inline int +tss_set(tss_t key, void *val) +{ + return TlsSetValue(key, val) ? 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; +} |