Soldier/JSON.cpp
/*
* File JSON.cpp part of the SimpleJSON Library - http://mjpa.in/json
*
* Copyright (C) 2010 Mike Anchor
*
* 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 "JSON.h"
/**
* Blocks off the public constructor
*
* @access private
*
*/
JSON::JSON()
{
}
/**
* Parses a complete JSON encoded string
* This is just a wrapper around the UNICODE Parse().
*
* @access public
*
* @param char* data The JSON text
*
* @return JSONValue* Returns a JSON Value representing the root, or NULL on error
*/
extern wchar_t *UTF8_2_UTF16(char *str);
JSONValue *JSON::Parse(const char *data)
{
wchar_t *w_data = UTF8_2_UTF16((char *)data);
if (!w_data)
return NULL;
JSONValue *value = JSON::Parse(w_data);
free(w_data);
return value;
}
/**
* Parses a complete JSON encoded string (UNICODE input version)
*
* @access public
*
* @param wchar_t* data The JSON text
*
* @return JSONValue* Returns a JSON Value representing the root, or NULL on error
*/
JSONValue *JSON::Parse(const wchar_t *data)
{
// Skip any preceding whitespace, end of data = no JSON = fail
if (!SkipWhitespace(&data))
return NULL;
// We need the start of a value here now...
JSONValue *value = JSONValue::Parse(&data);
if (value == NULL)
return NULL;
// Can be white space now and should be at the end of the string then...
if (SkipWhitespace(&data))
{
delete value;
return NULL;
}
// We're now at the end of the string
return value;
}
/**
* Turns the passed in JSONValue into a JSON encode string
*
* @access public
*
* @param JSONValue* value The root value
*
* @return std::wstring Returns a JSON encoded string representation of the given value
*/
std::wstring JSON::Stringify(const JSONValue *value)
{
if (value != NULL)
return value->Stringify();
else
return L"";
}
/**
* Skips over any whitespace characters (space, tab, \r or \n) defined by the JSON spec
*
* @access protected
*
* @param wchar_t** data Pointer to a wchar_t* that contains the JSON text
*
* @return bool Returns true if there is more data, or false if the end of the text was reached
*/
bool JSON::SkipWhitespace(const wchar_t **data)
{
while (**data != 0 && (**data == L' ' || **data == L'\t' || **data == L'\r' || **data == L'\n'))
(*data)++;
return **data != 0;
}
/**
* Extracts a JSON String as defined by the spec - "<some chars>"
* Any escaped characters are swapped out for their unescaped values
*
* @access protected
*
* @param wchar_t** data Pointer to a wchar_t* that contains the JSON text
* @param std::wstring& str Reference to a std::wstring to receive the extracted string
*
* @return bool Returns true on success, false on failure
*/
bool JSON::ExtractString(const wchar_t **data, std::wstring &str)
{
str = L"";
while (**data != 0)
{
// Save the char so we can change it if need be
wchar_t next_char = **data;
// Escaping something?
if (next_char == L'\\')
{
// Move over the escape char
(*data)++;
// Deal with the escaped char
switch (**data)
{
case L'"': next_char = L'"'; break;
case L'\\': next_char = L'\\'; break;
case L'/': next_char = L'/'; break;
case L'b': next_char = L'\b'; break;
case L'f': next_char = L'\f'; break;
case L'n': next_char = L'\n'; break;
case L'r': next_char = L'\r'; break;
case L't': next_char = L'\t'; break;
case L'u':
{
// We need 5 chars (4 hex + the 'u') or its not valid
if (!simplejson_wcsnlen(*data, 5))
return false;
// Deal with the chars
next_char = 0;
for (int i = 0; i < 4; i++)
{
// Do it first to move off the 'u' and leave us on the
// final hex digit as we move on by one later on
(*data)++;
next_char <<= 4;
// Parse the hex digit
if (**data >= '0' && **data <= '9')
next_char |= (**data - '0');
else if (**data >= 'A' && **data <= 'F')
next_char |= (10 + (**data - 'A'));
else if (**data >= 'a' && **data <= 'f')
next_char |= (10 + (**data - 'a'));
else
{
// Invalid hex digit = invalid JSON
return false;
}
}
break;
}
// By the spec, only the above cases are allowed
default:
return false;
}
}
// End of the string?
else if (next_char == L'"')
{
(*data)++;
str.reserve(); // Remove unused capacity
return true;
}
// Disallowed char?
else if (next_char < L' ' && next_char != L'\t')
{
// SPEC Violation: Allow tabs due to real world cases
return false;
}
// Add the next char
str += next_char;
// Move on
(*data)++;
}
// If we're here, the string ended incorrectly
return false;
}
/**
* Parses some text as though it is an integer
*
* @access protected
*
* @param wchar_t** data Pointer to a wchar_t* that contains the JSON text
*
* @return double Returns the double value of the number found
*/
double JSON::ParseInt(const wchar_t **data)
{
double integer = 0;
while (**data != 0 && **data >= '0' && **data <= '9')
integer = integer * 10 + (*(*data)++ - '0');
return integer;
}
/**
* Parses some text as though it is a decimal
*
* @access protected
*
* @param wchar_t** data Pointer to a wchar_t* that contains the JSON text
*
* @return double Returns the double value of the decimal found
*/
double JSON::ParseDecimal(const wchar_t **data)
{
double decimal = 0.0;
double factor = 0.1;
while (**data != 0 && **data >= '0' && **data <= '9')
{
int digit = (*(*data)++ - '0');
decimal = decimal + digit * factor;
factor *= 0.1;
}
return decimal;
}