Require Windows Vista / Server 2008 or greater.
This allows us to define pthread_cond_t as CONDITION_VARIABLE on
Windows.
I also expanded the only invocation of the WaitForSingleObject macro
and deleted the macro.
NOTE: I believe we can simply call the Windows WaitForSingleObject
function instead of WaitForSingleObjectEx(..., FALSE). The MSDN page for
WaitForSingleObject says:
To enter an alertable wait state, use the WaitForSingleObjectEx
function.
which implies that WaitForSingleObject enters a non-alertable wait state
and therefore WaitForSingleObject is equivalent to passing FALSE as the
bAlertable argument to WaitForSingleObjectEx.
Change-Id: Ief5b14b75cd3c8b02d2a26a67b3b2e6d8fa28ab2
diff --git a/aom_util/aom_thread.h b/aom_util/aom_thread.h
index bda8b75..61f3449 100644
--- a/aom_util/aom_thread.h
+++ b/aom_util/aom_thread.h
@@ -37,16 +37,10 @@
typedef HANDLE pthread_t;
typedef CRITICAL_SECTION pthread_mutex_t;
-#if _WIN32_WINNT >= 0x0600 // Windows Vista / Server 2008 or greater
-#define USE_WINDOWS_CONDITION_VARIABLE
+#if _WIN32_WINNT < 0x0600
+#error Windows Vista / Server 2008 or greater is required.
+#endif
typedef CONDITION_VARIABLE pthread_cond_t;
-#else
-typedef struct {
- HANDLE waiting_sem_;
- HANDLE received_sem_;
- HANDLE signal_event_;
-} pthread_cond_t;
-#endif // _WIN32_WINNT >= 0x600
#ifndef WINAPI_FAMILY_PARTITION
#define WINAPI_PARTITION_DESKTOP 1
@@ -64,11 +58,6 @@
#define THREADFN unsigned int __stdcall
#define THREAD_RETURN(val) (unsigned int)((DWORD_PTR)val)
-#if _WIN32_WINNT >= 0x0501 // Windows XP or greater
-#define WaitForSingleObject(obj, timeout) \
- WaitForSingleObjectEx(obj, timeout, FALSE /*bAlertable*/)
-#endif
-
static INLINE int pthread_create(pthread_t *const thread, const void *attr,
unsigned int(__stdcall *start)(void *),
void *arg) {
@@ -91,7 +80,8 @@
static INLINE int pthread_join(pthread_t thread, void **value_ptr) {
(void)value_ptr;
- return (WaitForSingleObject(thread, INFINITE) != WAIT_OBJECT_0 ||
+ return (WaitForSingleObjectEx(thread, INFINITE, FALSE /*bAlertable*/) !=
+ WAIT_OBJECT_0 ||
CloseHandle(thread) == 0);
}
@@ -99,11 +89,7 @@
static INLINE int pthread_mutex_init(pthread_mutex_t *const mutex,
void *mutexattr) {
(void)mutexattr;
-#if _WIN32_WINNT >= 0x0600 // Windows Vista / Server 2008 or greater
InitializeCriticalSectionEx(mutex, 0 /*dwSpinCount*/, 0 /*Flags*/);
-#else
- InitializeCriticalSection(mutex);
-#endif
return 0;
}
@@ -128,85 +114,31 @@
// Condition
static INLINE int pthread_cond_destroy(pthread_cond_t *const condition) {
- int ok = 1;
-#ifdef USE_WINDOWS_CONDITION_VARIABLE
(void)condition;
-#else
- ok &= (CloseHandle(condition->waiting_sem_) != 0);
- ok &= (CloseHandle(condition->received_sem_) != 0);
- ok &= (CloseHandle(condition->signal_event_) != 0);
-#endif
- return !ok;
+ return 0;
}
static INLINE int pthread_cond_init(pthread_cond_t *const condition,
void *cond_attr) {
(void)cond_attr;
-#ifdef USE_WINDOWS_CONDITION_VARIABLE
InitializeConditionVariable(condition);
-#else
- condition->waiting_sem_ = CreateSemaphore(NULL, 0, MAX_DECODE_THREADS, NULL);
- condition->received_sem_ = CreateSemaphore(NULL, 0, MAX_DECODE_THREADS, NULL);
- condition->signal_event_ = CreateEvent(NULL, FALSE, FALSE, NULL);
- if (condition->waiting_sem_ == NULL || condition->received_sem_ == NULL ||
- condition->signal_event_ == NULL) {
- pthread_cond_destroy(condition);
- return 1;
- }
-#endif
return 0;
}
static INLINE int pthread_cond_signal(pthread_cond_t *const condition) {
- int ok = 1;
-#ifdef USE_WINDOWS_CONDITION_VARIABLE
WakeConditionVariable(condition);
-#else
- if (WaitForSingleObject(condition->waiting_sem_, 0) == WAIT_OBJECT_0) {
- // a thread is waiting in pthread_cond_wait: allow it to be notified
- ok = SetEvent(condition->signal_event_);
- // wait until the event is consumed so the signaler cannot consume
- // the event via its own pthread_cond_wait.
- ok &= (WaitForSingleObject(condition->received_sem_, INFINITE) !=
- WAIT_OBJECT_0);
- }
-#endif
- return !ok;
+ return 0;
}
static INLINE int pthread_cond_broadcast(pthread_cond_t *const condition) {
- int ok = 1;
-#ifdef USE_WINDOWS_CONDITION_VARIABLE
WakeAllConditionVariable(condition);
-#else
- while (WaitForSingleObject(condition->waiting_sem_, 0) == WAIT_OBJECT_0) {
- // a thread is waiting in pthread_cond_wait: allow it to be notified
- ok &= SetEvent(condition->signal_event_);
- // wait until the event is consumed so the signaler cannot consume
- // the event via its own pthread_cond_wait.
- ok &= (WaitForSingleObject(condition->received_sem_, INFINITE) !=
- WAIT_OBJECT_0);
- }
-#endif
- return !ok;
+ return 0;
}
static INLINE int pthread_cond_wait(pthread_cond_t *const condition,
pthread_mutex_t *const mutex) {
int ok;
-#ifdef USE_WINDOWS_CONDITION_VARIABLE
ok = SleepConditionVariableCS(condition, mutex, INFINITE);
-#else
- // note that there is a consumer available so the signal isn't dropped in
- // pthread_cond_signal
- if (!ReleaseSemaphore(condition->waiting_sem_, 1, NULL)) return 1;
- // now unlock the mutex so pthread_cond_signal may be issued
- pthread_mutex_unlock(mutex);
- ok = (WaitForSingleObject(condition->signal_event_, INFINITE) ==
- WAIT_OBJECT_0);
- ok &= ReleaseSemaphore(condition->received_sem_, 1, NULL);
- pthread_mutex_lock(mutex);
-#endif
return !ok;
}
#elif defined(__OS2__)
