Files
ArduinoJson/src/Internals/JsonParser.cpp
Benoit Blanchon e25eaed75a Cleaned #includes
2014-11-04 10:01:21 +01:00

166 lines
3.7 KiB
C++

// Copyright Benoit Blanchon 2014
// MIT License
//
// Arduino JSON library
// https://github.com/bblanchon/ArduinoJson
#include "../../include/ArduinoJson/Internals/JsonParser.hpp"
#include <stdlib.h> // for strtol, strtod
#include <ctype.h>
#include "../../include/ArduinoJson/Internals/QuotedString.hpp"
#include "../../include/ArduinoJson/JsonArray.hpp"
#include "../../include/ArduinoJson/JsonBuffer.hpp"
#include "../../include/ArduinoJson/JsonObject.hpp"
using namespace ArduinoJson;
using namespace ArduinoJson::Internals;
void JsonParser::skipSpaces() {
while (isspace(*_ptr)) _ptr++;
}
bool JsonParser::skip(char charToSkip) {
skipSpaces();
if (*_ptr != charToSkip) return false;
_ptr++;
skipSpaces();
return true;
}
bool JsonParser::skip(const char *wordToSkip) {
const char *charToSkip = wordToSkip;
while (*charToSkip && *_ptr == *charToSkip) {
charToSkip++;
_ptr++;
}
return *charToSkip == '\0';
}
void JsonParser::parseAnythingTo(JsonVariant &destination) {
skipSpaces();
switch (*_ptr) {
case '[':
destination = parseArray();
break;
case 't':
case 'f':
parseBooleanTo(destination);
break;
case '-':
case '.':
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
parseNumberTo(destination);
break;
case 'n':
parseNullTo(destination);
break;
case '{':
destination = parseObject();
break;
case '\'':
case '\"':
destination = parseString();
break;
}
}
JsonArray &JsonParser::parseArray() {
if (!skip('[')) return JsonArray::invalid(); // missing opening bracket
if (isEnd()) return JsonArray::invalid(); // end of stream
JsonArray &array = _buffer->createArray();
if (skip(']')) return array; // empty array
for (;;) {
JsonVariant &child = array.add();
parseAnythingTo(child);
if (!child.success()) return JsonArray::invalid(); // child parsing failed
if (skip(']')) return array; // end of the array
if (!skip(',')) return JsonArray::invalid(); // comma is missing
}
}
void JsonParser::parseBooleanTo(JsonVariant &destination) {
bool value = *_ptr == 't';
if (skip(value ? "true" : "false"))
destination = value;
else
destination = JsonVariant::invalid();
}
void JsonParser::parseNumberTo(JsonVariant &destination) {
char *endOfLong;
long longValue = strtol(_ptr, &endOfLong, 10);
if (*endOfLong == '.') {
// stopped on a decimal separator
double doubleValue = strtod(_ptr, &_ptr);
uint8_t decimals = _ptr - endOfLong - 1;
destination.set(doubleValue, decimals);
} else {
_ptr = endOfLong;
destination = longValue;
}
}
void JsonParser::parseNullTo(JsonVariant &destination) {
if (skip("null"))
destination = static_cast<const char *>(NULL);
else
destination = JsonVariant::invalid();
}
JsonObject &JsonParser::parseObject() {
if (!skip('{')) return JsonObject::invalid(); // missing opening brace
if (isEnd()) return JsonObject::invalid(); // premature ending
JsonObject &object = _buffer->createObject();
if (skip('}')) return object; // empty object
for (;;) {
const char *key = parseString();
if (!key) break; // key parsing failed
if (!skip(':')) break; // colon is missing
JsonVariant &value = object[key];
parseAnythingTo(value);
if (!value.success()) break; // value parsing failed
if (skip('}')) return object; // end of the object
if (!skip(',')) break; // comma is missing
}
return JsonObject::invalid();
}
const char *JsonParser::parseString() {
return QuotedString::extractFrom(_ptr, &_ptr);
}