File content as of revision 20:505d29d5bdfc:

/*
 * Parser.cpp
 *
 * Created on: Nov 1, 2013
 * * Authors: Vincent Wochnik <v.wochnik@gmail.com>
 *
 * Copyright (c) 2013 Cumulocity GmbH
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include <assert.h>
#include <stdio.h>
#include <ctype.h>
#include "Parser.h"

#define STATE_BLANK 0
#define STATE_STRUCTURE 1
#define STATE_VALUE 2
#define STATE_INQUOTES 3
#define STATE_AFTERQUOTE 4
#define STATE_COMPLETE 5
#define STATE_ERROR 6


/*-------------------------------------------------------------------------*/
Parser::Parser()
{
	reset();
}
/*-------------------------------------------------------------------------*/
uint8_t Parser::readFrom(AbstractDataSource& source, ParsedRecord& record)
{
	reset();
	record.clear();

	int status = -1;
	char read;
	while (_state < STATE_COMPLETE) {
		read = source.read();
		status = source.status();
//		if (isprint(read)) {
//			printf("%4c: %u\n", read, status);
//		} else {
//			printf("#%04x: %u\n", read, status);
//		}
		if (read > 0 || status == DS_STATUS_OK)
			parse(read);
		else
			break;
	}
//	printf("Parser: [E]while! %u, %d\r\n", _state, status);
	if (_state == STATE_COMPLETE) { // successfully read record
		if (!record.set(_buffer, _count))
			return PARSER_INTERNAL_ERROR;
		else
			return PARSER_SUCCESS;
	} else if (_state == STATE_BLANK) {
		if (status == DS_STATUS_CLOSED)
			return PARSER_END_OF_RESPONSE;
		else if (status == DS_STATUS_TIMEOUT)
			return PARSER_TIMEOUT_ERROR;
		else
			return PARSER_INTERNAL_ERROR;
	} else {
		if (status == DS_STATUS_TIMEOUT)
			return PARSER_TIMEOUT_ERROR;
		else if (status == DS_STATUS_ERROR)
			return PARSER_INTERNAL_ERROR;
		else
			return PARSER_PARSE_ERROR;
	}
}
/*-------------------------------------------------------------------------*/
void Parser::parse(char c)
{
	if (_ptr-_buffer >= SMARTREST_PARSER_BUFFER_SIZE) {
		_state = STATE_ERROR;
		return;
	}

	switch (_state)
	{
	case STATE_BLANK: _state = STATE_STRUCTURE;
	case STATE_STRUCTURE:
		switch (c)
		{
		case ' ':
		case '\t':
		case '\r': break;
		case '"': _state = STATE_INQUOTES; break;
		case ',': close(); break;
		case '\0':
		case '\n':
			if (_count==0 && _length==0) {
				_state = STATE_BLANK;
			} else {
				close();
				_state = STATE_COMPLETE;
			}
			break;
		default:
			if (_length > 0) {
				_state = STATE_ERROR;
			} else {
				_state = STATE_VALUE;
				parse(c);
			}
			break;
		}
		break;
	case STATE_VALUE:
		switch (c)
		{
		case ',':
		case '\n':	_state = STATE_STRUCTURE; parse(c); break;
		case '"': 	_state = STATE_ERROR; break;
		default:
			if ((c == ' ') || (c == '\t') || (c == '\r'))
				_trailing++;
			else
				_trailing = 0;
			append(c);
			break;
		}
		break;
	case STATE_INQUOTES:
		switch (c)
		{
		case '"': _state = STATE_AFTERQUOTE; break;
		default: append(c);	break;
		}
		break;
	case STATE_AFTERQUOTE:
		switch (c)
		{
		case '"': append(c); _state = STATE_INQUOTES; break;
		default: _state = STATE_STRUCTURE; parse(c); break;
		}
		break;
	}
}
/*-------------------------------------------------------------------------*/
void Parser::append(char c)
{
	*_ptr++ = c;
	_length++;
}
/*-------------------------------------------------------------------------*/
void Parser::close()
{
	_ptr -= _trailing;
	*_ptr++ = 0;
	_trailing = 0;
	_length = 0;
	_count++;
}
/*-------------------------------------------------------------------------*/
void Parser::reset()
{
	_state = STATE_BLANK;
	_ptr = _buffer;
	_count = 0;
	_trailing = 0;
	_length = 0;
}
/*-------------------------------------------------------------------------*/