mbed-os/drivers/RawSerial.cpp

94 lines
2.4 KiB
C++

/* mbed Microcontroller Library
* Copyright (c) 2006-2013 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "drivers/RawSerial.h"
#include "platform/mbed_wait_api.h"
#include <cstdarg>
#if DEVICE_SERIAL
#define STRING_STACK_LIMIT 120
namespace mbed {
RawSerial::RawSerial(PinName tx, PinName rx, int baud) : SerialBase(tx, rx, baud) {
// No lock needed in the constructor
}
int RawSerial::getc() {
lock();
int ret = _base_getc();
unlock();
return ret;
}
int RawSerial::putc(int c) {
lock();
int ret = _base_putc(c);
unlock();
return ret;
}
int RawSerial::puts(const char *str) {
lock();
while (*str)
putc(*str ++);
unlock();
return 0;
}
// Experimental support for printf in RawSerial. No Stream inheritance
// means we can't call printf() directly, so we use sprintf() instead.
// We only call malloc() for the sprintf() buffer if the buffer
// length is above a certain threshold, otherwise we use just the stack.
int RawSerial::printf(const char *format, ...) {
lock();
std::va_list arg;
va_start(arg, format);
// ARMCC microlib does not properly handle a size of 0.
// As a workaround supply a dummy buffer with a size of 1.
char dummy_buf[1];
int len = vsnprintf(dummy_buf, sizeof(dummy_buf), format, arg);
if (len < STRING_STACK_LIMIT) {
char temp[STRING_STACK_LIMIT];
vsprintf(temp, format, arg);
puts(temp);
} else {
char *temp = new char[len + 1];
vsprintf(temp, format, arg);
puts(temp);
delete[] temp;
}
va_end(arg);
unlock();
return len;
}
/** Acquire exclusive access to this serial port
*/
void RawSerial::lock() {
// No lock used - external synchronization required
}
/** Release exclusive access to this serial port
*/
void RawSerial::unlock() {
// No lock used - external synchronization required
}
} // namespace mbed
#endif