rtcm.cpp 2.58 KB
/****************************************************************************
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 * modification, are permitted provided that the following conditions
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 *    used to endorse or promote products derived from this software
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#include "rtcm.h"
#include <cstring>

RTCMParsing::RTCMParsing()
{
	reset();
}

RTCMParsing::~RTCMParsing()
{
	delete[] _buffer;
}

void RTCMParsing::reset()
{
	if (!_buffer) {
		_buffer = new uint8_t[RTCM_INITIAL_BUFFER_LENGTH];
		_buffer_len = RTCM_INITIAL_BUFFER_LENGTH;
	}

	_pos = 0;
	_message_length = _buffer_len;
}

bool RTCMParsing::addByte(uint8_t b)
{
	if (!_buffer) {
		return false;
	}

	_buffer[_pos++] = b;

	if (_pos == 3) {
		_message_length = (((uint16_t)_buffer[1] & 3) << 8) | (_buffer[2]);

		if (_message_length + 6 > _buffer_len) {
			uint16_t new_buffer_len = _message_length + 6;
			uint8_t *new_buffer = new uint8_t[new_buffer_len];

			if (!new_buffer) {
				delete[](_buffer);
				_buffer = nullptr;
				return false;
			}

			memcpy(new_buffer, _buffer, 3);
			delete[](_buffer);
			_buffer = new_buffer;
			_buffer_len = new_buffer_len;
		}
	}

	return _message_length + 6 == _pos;
}