Mutex.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2012 ARM Limited
00003  *
00004  * Permission is hereby granted, free of charge, to any person obtaining a copy
00005  * of this software and associated documentation files (the "Software"), to deal
00006  * in the Software without restriction, including without limitation the rights
00007  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00008  * copies of the Software, and to permit persons to whom the Software is
00009  * furnished to do so, subject to the following conditions:
00010  *
00011  * The above copyright notice and this permission notice shall be included in
00012  * all copies or substantial portions of the Software.
00013  *
00014  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00015  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00016  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00017  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00018  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
00020  * SOFTWARE.
00021  */
00022 #include "rtos/Mutex.h"
00023 
00024 #include <string.h>
00025 #include "mbed_error.h"
00026 #include "mbed_assert.h"
00027 
00028 namespace rtos {
00029 
00030 Mutex::Mutex(): _count(0)
00031 {
00032     constructor();
00033 }
00034 
00035 Mutex::Mutex(const char *name)
00036 {
00037     constructor(name);
00038 }
00039 
00040 void Mutex::constructor(const char *name)
00041 {
00042     memset(&_obj_mem, 0, sizeof(_obj_mem));
00043     osMutexAttr_t attr = { 0 };
00044     attr.name = name ? name : "aplication_unnamed_mutex";
00045     attr.cb_mem = &_obj_mem;
00046     attr.cb_size = sizeof(_obj_mem);
00047     attr.attr_bits = osMutexRecursive | osMutexPrioInherit | osMutexRobust;
00048     _id = osMutexNew(&attr);
00049     MBED_ASSERT(_id);
00050 }
00051 
00052 osStatus Mutex::lock(uint32_t millisec) {
00053     osStatus status = osMutexAcquire(_id, millisec);
00054     if (osOK == status) {
00055         _count++;
00056     }
00057     return status;
00058 }
00059 
00060 bool Mutex::trylock() {
00061     if (osMutexAcquire(_id, 0) == osOK) {
00062         _count++;
00063         return true;
00064     } else {
00065         return false;
00066     }
00067 }
00068 
00069 osStatus Mutex::unlock() {
00070     _count--;
00071     return osMutexRelease(_id);
00072 }
00073 
00074 osThreadId Mutex::get_owner() {
00075     return osMutexGetOwner(_id);
00076 }
00077 
00078 Mutex::~Mutex() {
00079     osMutexDelete(_id);
00080 }
00081 
00082 }