ardupilot/libraries/AP_HAL_ChibiOS/Semaphores.cpp

58 lines
1.5 KiB
C++

/*
* This file is free software: you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This file is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Code by Andrew Tridgell and Siddharth Bharat Purohit
*/
#include <AP_HAL/AP_HAL.h>
#if CONFIG_HAL_BOARD == HAL_BOARD_CHIBIOS
#include "Semaphores.h"
extern const AP_HAL::HAL& hal;
using namespace ChibiOS;
bool Semaphore::give()
{
chMtxUnlock(&_lock);
return true;
}
bool Semaphore::take(uint32_t timeout_ms)
{
if (timeout_ms == HAL_SEMAPHORE_BLOCK_FOREVER) {
chMtxLock(&_lock);
return true;
}
if (take_nonblocking()) {
return true;
}
uint64_t start = AP_HAL::micros64();
do {
hal.scheduler->delay_microseconds(200);
if (take_nonblocking()) {
return true;
}
} while ((AP_HAL::micros64() - start) < timeout_ms*1000);
return false;
}
bool Semaphore::take_nonblocking()
{
return chMtxTryLock(&_lock);
}
#endif // CONFIG_HAL_BOARD