thodg/libgit2/src/win32/pthread.c

• Show log

  Commit

• Hash : f087bc24
  Author :
  Date : 2013-08-27T12:08:55
  

  Convert to our own SRWLOCK type on Win32

Download

• src/win32/pthread.c

• /*
   * Copyright (C) the libgit2 contributors. All rights reserved.
   *
   * This file is part of libgit2, distributed under the GNU GPL v2 with
   * a Linking Exception. For full terms see the included COPYING file.
   */
  
  #include "pthread.h"
  
  int pthread_create(
  	pthread_t *GIT_RESTRICT thread,
  	const pthread_attr_t *GIT_RESTRICT attr,
  	void *(*start_routine)(void*),
  	void *GIT_RESTRICT arg)
  {
  	GIT_UNUSED(attr);
  	*thread = CreateThread(
  		NULL, 0, (LPTHREAD_START_ROUTINE)start_routine, arg, 0, NULL);
  	return *thread ? 0 : -1;
  }
  
  int pthread_join(pthread_t thread, void **value_ptr)
  {
  	DWORD ret = WaitForSingleObject(thread, INFINITE);
  
  	if (ret == WAIT_OBJECT_0) {
  		if (value_ptr != NULL) {
  			*value_ptr = NULL;
  			GetExitCodeThread(thread, (void *)value_ptr);
  		}
  		CloseHandle(thread);
  		return 0;
  	}
  
  	return -1;
  }
  
  int pthread_mutex_init(
  	pthread_mutex_t *GIT_RESTRICT mutex,
  	const pthread_mutexattr_t *GIT_RESTRICT mutexattr)
  {
  	GIT_UNUSED(mutexattr);
  	InitializeCriticalSection(mutex);
  	return 0;
  }
  
  int pthread_mutex_destroy(pthread_mutex_t *mutex)
  {
  	DeleteCriticalSection(mutex);
  	return 0;
  }
  
  int pthread_mutex_lock(pthread_mutex_t *mutex)
  {
  	EnterCriticalSection(mutex);
  	return 0;
  }
  
  int pthread_mutex_unlock(pthread_mutex_t *mutex)
  {
  	LeaveCriticalSection(mutex);
  	return 0;
  }
  
  int pthread_cond_init(pthread_cond_t *cond, const pthread_condattr_t *attr)
  {
  	/* We don't support non-default attributes. */
  	if (attr)
  		return EINVAL;
  
  	/* This is an auto-reset event. */
  	*cond = CreateEventW(NULL, FALSE, FALSE, NULL);
  	assert(*cond);
  
  	/* If we can't create the event, claim that the reason was out-of-memory.
  	 * The actual reason can be fetched with GetLastError(). */
  	return *cond ? 0 : ENOMEM;
  }
  
  int pthread_cond_destroy(pthread_cond_t *cond)
  {
  	BOOL closed;
  
  	if (!cond)
  		return EINVAL;
  
  	closed = CloseHandle(*cond);
  	assert(closed);
  	GIT_UNUSED(closed);
  
  	*cond = NULL;
  	return 0;
  }
  
  int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
  {
  	int error;
  	DWORD wait_result;
  
  	if (!cond || !mutex)
  		return EINVAL;
  
  	/* The caller must be holding the mutex. */
  	error = pthread_mutex_unlock(mutex);
  
  	if (error)
  		return error;
  
  	wait_result = WaitForSingleObject(*cond, INFINITE);
  	assert(WAIT_OBJECT_0 == wait_result);
  	GIT_UNUSED(wait_result);
  
  	return pthread_mutex_lock(mutex);
  }
  
  int pthread_cond_signal(pthread_cond_t *cond)
  {
  	BOOL signaled;
  
  	if (!cond)
  		return EINVAL;
  
  	signaled = SetEvent(*cond);
  	assert(signaled);
  	GIT_UNUSED(signaled);
  
  	return 0;
  }
  
  /* pthread_cond_broadcast is not implemented because doing so with just
   * Win32 events is quite complicated, and no caller in libgit2 uses it
   * yet.
   */
  int pthread_num_processors_np(void)
  {
  	DWORD_PTR p, s;
  	int n = 0;
  
  	if (GetProcessAffinityMask(GetCurrentProcess(), &p, &s))
  		for (; p; p >>= 1)
  			n += p&1;
  
  	return n ? n : 1;
  }
  
  
  static HINSTANCE win32_kernel32_dll;
  
  typedef void (WINAPI *win32_srwlock_fn)(GIT_SRWLOCK *);
  
  static win32_srwlock_fn win32_srwlock_initialize;
  static win32_srwlock_fn win32_srwlock_acquire_shared;
  static win32_srwlock_fn win32_srwlock_release_shared;
  static win32_srwlock_fn win32_srwlock_acquire_exclusive;
  static win32_srwlock_fn win32_srwlock_release_exclusive;
  
  int pthread_rwlock_init(
  	pthread_rwlock_t *GIT_RESTRICT lock,
  	const pthread_rwlockattr_t *GIT_RESTRICT attr)
  {
  	(void)attr;
  
  	if (win32_srwlock_initialize)
  		win32_srwlock_initialize(&lock->native.srwl);
  	else
  		InitializeCriticalSection(&lock->native.csec);
  
  	return 0;
  }
  
  int pthread_rwlock_rdlock(pthread_rwlock_t *lock)
  {
  	if (win32_srwlock_acquire_shared)
  		win32_srwlock_acquire_shared(&lock->native.srwl);
  	else
  		EnterCriticalSection(&lock->native.csec);
  
  	return 0;
  }
  
  int pthread_rwlock_rdunlock(pthread_rwlock_t *lock)
  {
  	if (win32_srwlock_release_shared)
  		win32_srwlock_release_shared(&lock->native.srwl);
  	else
  		LeaveCriticalSection(&lock->native.csec);
  
  	return 0;
  }
  
  int pthread_rwlock_wrlock(pthread_rwlock_t *lock)
  {
  	if (win32_srwlock_acquire_exclusive)
  		win32_srwlock_acquire_exclusive(&lock->native.srwl);
  	else
  		EnterCriticalSection(&lock->native.csec);
  
  	return 0;
  }
  
  int pthread_rwlock_wrunlock(pthread_rwlock_t *lock)
  {
  	if (win32_srwlock_release_exclusive)
  		win32_srwlock_release_exclusive(&lock->native.srwl);
  	else
  		LeaveCriticalSection(&lock->native.csec);
  
  	return 0;
  }
  
  int pthread_rwlock_destroy(pthread_rwlock_t *lock)
  {
  	if (!win32_srwlock_initialize)
  		DeleteCriticalSection(&lock->native.csec);
  	git__memzero(lock, sizeof(*lock));
  	return 0;
  }
  
  
  int win32_pthread_initialize(void)
  {
  	if (win32_kernel32_dll)
  		return 0;
  
  	win32_kernel32_dll = LoadLibrary("Kernel32.dll");
  	if (!win32_kernel32_dll) {
  		giterr_set(GITERR_OS, "Could not load Kernel32.dll!");
  		return -1;
  	}
  
  	win32_srwlock_initialize = (win32_srwlock_fn)
  		GetProcAddress(win32_kernel32_dll, "InitializeSRWLock");
  	win32_srwlock_acquire_shared = (win32_srwlock_fn)
  		GetProcAddress(win32_kernel32_dll, "AcquireSRWLockShared");
  	win32_srwlock_release_shared = (win32_srwlock_fn)
  		GetProcAddress(win32_kernel32_dll, "ReleaseSRWLockShared");
  	win32_srwlock_acquire_exclusive = (win32_srwlock_fn)
  		GetProcAddress(win32_kernel32_dll, "AcquireSRWLockExclusive");
  	win32_srwlock_release_exclusive = (win32_srwlock_fn)
  		GetProcAddress(win32_kernel32_dll, "ReleaseSRWLockExclusive");
  
  	return 0;
  }
  
  int win32_pthread_shutdown(void)
  {
  	if (win32_kernel32_dll) {
  		FreeLibrary(win32_kernel32_dll);
  		win32_kernel32_dll = NULL;
  	}
  
  	return 0;
  }
  

Download