1 /*-------------------------------------------------------------------------
2  * drawElements Thread Library
3  * ---------------------------
4  *
5  * Copyright 2014 The Android Open Source Project
6  *
7  * Licensed under the Apache License, Version 2.0 (the "License");
8  * you may not use this file except in compliance with the License.
9  * You may obtain a copy of the License at
10  *
11  *      http://www.apache.org/licenses/LICENSE-2.0
12  *
13  * Unless required by applicable law or agreed to in writing, software
14  * distributed under the License is distributed on an "AS IS" BASIS,
15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16  * See the License for the specific language governing permissions and
17  * limitations under the License.
18  *
19  *//*!
20  * \file
21  * \brief Win32 implementation of semaphore.
22  *//*--------------------------------------------------------------------*/
23 
24 #include "deSemaphore.h"
25 
26 #if (DE_OS == DE_OS_WIN32 || DE_OS == DE_OS_WINCE)
27 
28 #define VC_EXTRALEAN
29 #define WIN32_LEAN_AND_MEAN
30 #include <windows.h>
31 
32 #define WIN32_SEM_MAX_VALUE 0x7fffffff
33 
34 DE_STATIC_ASSERT(sizeof(deSemaphore) >= sizeof(HANDLE));
35 
deSemaphore_create(int initialValue,const deSemaphoreAttributes * attributes)36 deSemaphore deSemaphore_create (int initialValue, const deSemaphoreAttributes* attributes)
37 {
38 	HANDLE	handle;
39 
40 	DE_UNREF(attributes);
41 
42 	handle = CreateSemaphore(DE_NULL, initialValue, WIN32_SEM_MAX_VALUE, DE_NULL);
43 	if (!handle)
44 		return 0;
45 
46 	DE_ASSERT((deSemaphore)handle != 0);
47 
48 	return (deSemaphore)handle;
49 }
50 
deSemaphore_destroy(deSemaphore semaphore)51 void deSemaphore_destroy (deSemaphore semaphore)
52 {
53 	HANDLE	handle	= (HANDLE)semaphore;
54 	CloseHandle(handle);
55 }
56 
deSemaphore_increment(deSemaphore semaphore)57 void deSemaphore_increment (deSemaphore semaphore)
58 {
59 	HANDLE	handle	= (HANDLE)semaphore;
60 	BOOL	ret		= ReleaseSemaphore(handle, 1, DE_NULL);
61 	DE_ASSERT(ret);
62 	DE_UNREF(ret);
63 }
64 
deSemaphore_decrement(deSemaphore semaphore)65 void deSemaphore_decrement (deSemaphore semaphore)
66 {
67 	HANDLE	handle	= (HANDLE)semaphore;
68 	DWORD	ret		= WaitForSingleObject(handle, INFINITE);
69 	DE_ASSERT(ret == WAIT_OBJECT_0);
70 	DE_UNREF(ret);
71 }
72 
deSemaphore_tryDecrement(deSemaphore semaphore)73 deBool deSemaphore_tryDecrement (deSemaphore semaphore)
74 {
75 	HANDLE	handle	= (HANDLE)semaphore;
76 	DWORD	ret		= WaitForSingleObject(handle, 0);
77 	return (ret == WAIT_OBJECT_0);
78 }
79 
80 #endif /* DE_OS */
81