ioq3/code/qcommon/json.h

353 lines
9.9 KiB
C

/*
===========================================================================
Copyright (C) 2016 James Canete
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
===========================================================================
*/
#ifndef JSON_H
#define JSON_H
enum
{
JSONTYPE_STRING, // string
JSONTYPE_OBJECT, // object
JSONTYPE_ARRAY, // array
JSONTYPE_VALUE, // number, true, false, or null
JSONTYPE_ERROR // out of data
};
// --------------------------------------------------------------------------
// Array Functions
// --------------------------------------------------------------------------
// Get pointer to first value in array
// When given pointer to an array, returns pointer to the first
// returns NULL if array is empty or not an array.
const char *JSON_ArrayGetFirstValue(const char *json, const char *jsonEnd);
// Get pointer to next value in array
// When given pointer to a value, returns pointer to the next value
// returns NULL when no next value.
const char *JSON_ArrayGetNextValue(const char *json, const char *jsonEnd);
// Get pointers to values in an array
// returns 0 if not an array, array is empty, or out of data
// returns number of values in the array and copies into index if successful
unsigned int JSON_ArrayGetIndex(const char *json, const char *jsonEnd, const char **indexes, unsigned int numIndexes);
// Get pointer to indexed value from array
// returns NULL if not an array, no index, or out of data
const char *JSON_ArrayGetValue(const char *json, const char *jsonEnd, unsigned int index);
// --------------------------------------------------------------------------
// Object Functions
// --------------------------------------------------------------------------
// Get pointer to named value from object
// returns NULL if not an object, name not found, or out of data
const char *JSON_ObjectGetNamedValue(const char *json, const char *jsonEnd, const char *name);
// --------------------------------------------------------------------------
// Value Functions
// --------------------------------------------------------------------------
// Get type of value
// returns JSONTYPE_ERROR if out of data
unsigned int JSON_ValueGetType(const char *json, const char *jsonEnd);
// Get value as string
// returns 0 if out of data
// returns length and copies into string if successful, including terminating nul.
// string values are stripped of enclosing quotes but not escaped
unsigned int JSON_ValueGetString(const char *json, const char *jsonEnd, char *outString, unsigned int stringLen);
// Get value as appropriate type
// returns 0 if value is false, value is null, or out of data
// returns 1 if value is true
// returns value otherwise
double JSON_ValueGetDouble(const char *json, const char *jsonEnd);
float JSON_ValueGetFloat(const char *json, const char *jsonEnd);
int JSON_ValueGetInt(const char *json, const char *jsonEnd);
#endif
#ifdef JSON_IMPLEMENTATION
#include <stdio.h>
// --------------------------------------------------------------------------
// Internal Functions
// --------------------------------------------------------------------------
static const char *JSON_SkipSeparators(const char *json, const char *jsonEnd);
static const char *JSON_SkipString(const char *json, const char *jsonEnd);
static const char *JSON_SkipStruct(const char *json, const char *jsonEnd);
static const char *JSON_SkipValue(const char *json, const char *jsonEnd);
static const char *JSON_SkipValueAndSeparators(const char *json, const char *jsonEnd);
#define IS_SEPARATOR(x) ((x) == ' ' || (x) == '\t' || (x) == '\n' || (x) == '\r' || (x) == ',' || (x) == ':')
#define IS_STRUCT_OPEN(x) ((x) == '{' || (x) == '[')
#define IS_STRUCT_CLOSE(x) ((x) == '}' || (x) == ']')
static const char *JSON_SkipSeparators(const char *json, const char *jsonEnd)
{
while (json < jsonEnd && IS_SEPARATOR(*json))
json++;
return json;
}
static const char *JSON_SkipString(const char *json, const char *jsonEnd)
{
for (json++; json < jsonEnd && *json != '"'; json++)
if (*json == '\\')
json++;
return (json + 1 > jsonEnd) ? jsonEnd : json + 1;
}
static const char *JSON_SkipStruct(const char *json, const char *jsonEnd)
{
json = JSON_SkipSeparators(json + 1, jsonEnd);
while (json < jsonEnd && !IS_STRUCT_CLOSE(*json))
json = JSON_SkipValueAndSeparators(json, jsonEnd);
return (json + 1 > jsonEnd) ? jsonEnd : json + 1;
}
static const char *JSON_SkipValue(const char *json, const char *jsonEnd)
{
if (json >= jsonEnd)
return jsonEnd;
else if (*json == '"')
json = JSON_SkipString(json, jsonEnd);
else if (IS_STRUCT_OPEN(*json))
json = JSON_SkipStruct(json, jsonEnd);
else
{
while (json < jsonEnd && !IS_SEPARATOR(*json) && !IS_STRUCT_CLOSE(*json))
json++;
}
return json;
}
static const char *JSON_SkipValueAndSeparators(const char *json, const char *jsonEnd)
{
json = JSON_SkipValue(json, jsonEnd);
return JSON_SkipSeparators(json, jsonEnd);
}
// returns 0 if value requires more parsing, 1 if no more data/false/null, 2 if true
static unsigned int JSON_NoParse(const char *json, const char *jsonEnd)
{
if (!json || json >= jsonEnd || *json == 'f' || *json == 'n')
return 1;
if (*json == 't')
return 2;
return 0;
}
// --------------------------------------------------------------------------
// Array Functions
// --------------------------------------------------------------------------
const char *JSON_ArrayGetFirstValue(const char *json, const char *jsonEnd)
{
if (!json || json >= jsonEnd || !IS_STRUCT_OPEN(*json))
return NULL;
json = JSON_SkipSeparators(json + 1, jsonEnd);
return (json >= jsonEnd || IS_STRUCT_CLOSE(*json)) ? NULL : json;
}
const char *JSON_ArrayGetNextValue(const char *json, const char *jsonEnd)
{
if (!json || json >= jsonEnd || IS_STRUCT_CLOSE(*json))
return NULL;
json = JSON_SkipValueAndSeparators(json, jsonEnd);
return (json >= jsonEnd || IS_STRUCT_CLOSE(*json)) ? NULL : json;
}
unsigned int JSON_ArrayGetIndex(const char *json, const char *jsonEnd, const char **indexes, unsigned int numIndexes)
{
unsigned int length = 0;
for (json = JSON_ArrayGetFirstValue(json, jsonEnd); json; json = JSON_ArrayGetNextValue(json, jsonEnd))
{
if (indexes && numIndexes)
{
*indexes++ = json;
numIndexes--;
}
length++;
}
return length;
}
const char *JSON_ArrayGetValue(const char *json, const char *jsonEnd, unsigned int index)
{
for (json = JSON_ArrayGetFirstValue(json, jsonEnd); json && index; json = JSON_ArrayGetNextValue(json, jsonEnd))
index--;
return json;
}
// --------------------------------------------------------------------------
// Object Functions
// --------------------------------------------------------------------------
const char *JSON_ObjectGetNamedValue(const char *json, const char *jsonEnd, const char *name)
{
unsigned int nameLen = strlen(name);
for (json = JSON_ArrayGetFirstValue(json, jsonEnd); json; json = JSON_ArrayGetNextValue(json, jsonEnd))
{
if (*json == '"')
{
const char *thisNameStart, *thisNameEnd;
thisNameStart = json + 1;
json = JSON_SkipString(json, jsonEnd);
thisNameEnd = json - 1;
json = JSON_SkipSeparators(json, jsonEnd);
if ((unsigned int)(thisNameEnd - thisNameStart) == nameLen)
if (strncmp(thisNameStart, name, nameLen) == 0)
return json;
}
}
return NULL;
}
// --------------------------------------------------------------------------
// Value Functions
// --------------------------------------------------------------------------
unsigned int JSON_ValueGetType(const char *json, const char *jsonEnd)
{
if (!json || json >= jsonEnd)
return JSONTYPE_ERROR;
else if (*json == '"')
return JSONTYPE_STRING;
else if (*json == '{')
return JSONTYPE_OBJECT;
else if (*json == '[')
return JSONTYPE_ARRAY;
return JSONTYPE_VALUE;
}
unsigned int JSON_ValueGetString(const char *json, const char *jsonEnd, char *outString, unsigned int stringLen)
{
const char *stringEnd, *stringStart;
if (!json)
{
*outString = '\0';
return 0;
}
stringStart = json;
stringEnd = JSON_SkipValue(stringStart, jsonEnd);
if (stringEnd >= jsonEnd)
{
*outString = '\0';
return 0;
}
// skip enclosing quotes if they exist
if (*stringStart == '"')
stringStart++;
if (*(stringEnd - 1) == '"')
stringEnd--;
stringLen--;
if (stringLen > stringEnd - stringStart)
stringLen = stringEnd - stringStart;
json = stringStart;
while (stringLen--)
*outString++ = *json++;
*outString = '\0';
return stringEnd - stringStart;
}
double JSON_ValueGetDouble(const char *json, const char *jsonEnd)
{
char cValue[256];
double dValue = 0.0;
unsigned int np = JSON_NoParse(json, jsonEnd);
if (np)
return (double)(np - 1);
if (!JSON_ValueGetString(json, jsonEnd, cValue, 256))
return 0.0;
sscanf(cValue, "%lf", &dValue);
return dValue;
}
float JSON_ValueGetFloat(const char *json, const char *jsonEnd)
{
char cValue[256];
float fValue = 0.0f;
unsigned int np = JSON_NoParse(json, jsonEnd);
if (np)
return (float)(np - 1);
if (!JSON_ValueGetString(json, jsonEnd, cValue, 256))
return 0.0f;
sscanf(cValue, "%f", &fValue);
return fValue;
}
int JSON_ValueGetInt(const char *json, const char *jsonEnd)
{
char cValue[256];
int iValue = 0;
unsigned int np = JSON_NoParse(json, jsonEnd);
if (np)
return np - 1;
if (!JSON_ValueGetString(json, jsonEnd, cValue, 256))
return 0;
sscanf(cValue, "%d", &iValue);
return iValue;
}
#undef IS_SEPARATOR
#undef IS_STRUCT_OPEN
#undef IS_STRUCT_CLOSE
#endif