godot/core/io/json.cpp

474 lines
9.9 KiB
C++

/*************************************************************************/
/* json.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
/* */
/* 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"
#include "print_string.h"
const char * JSON::tk_name[TK_MAX] = {
"'{'",
"'}'",
"'['",
"']'",
"identifier",
"string",
"number",
"':'",
"','",
"EOF",
};
String JSON::_print_var(const Variant& p_var) {
switch(p_var.get_type()) {
case Variant::NIL: return "null";
case Variant::BOOL: return p_var.operator bool() ? "true": "false";
case Variant::INT: return itos(p_var);
case Variant::REAL: return rtos(p_var);
case Variant::POOL_INT_ARRAY:
case Variant::POOL_REAL_ARRAY:
case Variant::POOL_STRING_ARRAY:
case Variant::ARRAY: {
String s = "[";
Array a = p_var;
for(int i=0;i<a.size();i++) {
if (i>0)
s+=", ";
s+=_print_var(a[i]);
}
s+="]";
return s;
};
case Variant::DICTIONARY: {
String s = "{";
Dictionary d = p_var;
List<Variant> keys;
d.get_key_list(&keys);
for (List<Variant>::Element *E=keys.front();E;E=E->next()) {
if (E!=keys.front())
s+=", ";
s+=_print_var(String(E->get()));
s+=":";
s+=_print_var(d[E->get()]);
}
s+="}";
return s;
};
default: return "\""+String(p_var).json_escape()+"\"";
}
}
String JSON::print(const Variant& p_var) {
return _print_var(p_var);
}
Error JSON::_get_token(const CharType *p_str, int &idx, int p_len, Token& r_token,int &line,String &r_err_str) {
while (true) {
switch(p_str[idx]) {
case '\n': {
line++;
idx++;
break;
};
case 0: {
r_token.type=TK_EOF;
return OK;
} break;
case '{': {
r_token.type=TK_CURLY_BRACKET_OPEN;
idx++;
return OK;
};
case '}': {
r_token.type=TK_CURLY_BRACKET_CLOSE;
idx++;
return OK;
};
case '[': {
r_token.type=TK_BRACKET_OPEN;
idx++;
return OK;
};
case ']': {
r_token.type=TK_BRACKET_CLOSE;
idx++;
return OK;
};
case ':': {
r_token.type=TK_COLON;
idx++;
return OK;
};
case ',': {
r_token.type=TK_COMMA;
idx++;
return OK;
};
case '"': {
idx++;
String str;
while(true) {
if (p_str[idx]==0) {
r_err_str="Unterminated String";
return ERR_PARSE_ERROR;
} else if (p_str[idx]=='"') {
idx++;
break;
} else if (p_str[idx]=='\\') {
//escaped characters...
idx++;
CharType next = p_str[idx];
if (next==0) {
r_err_str="Unterminated String";
return ERR_PARSE_ERROR;
}
CharType res=0;
switch(next) {
case 'b': res=8; break;
case 't': res=9; break;
case 'n': res=10; break;
case 'f': res=12; break;
case 'r': res=13; break;
case 'u': {
//hexnumbarh - oct is deprecated
for(int j=0;j<4;j++) {
CharType c = p_str[idx+j+1];
if (c==0) {
r_err_str="Unterminated String";
return ERR_PARSE_ERROR;
}
if (!((c>='0' && c<='9') || (c>='a' && c<='f') || (c>='A' && c<='F'))) {
r_err_str="Malformed hex constant in string";
return ERR_PARSE_ERROR;
}
CharType v;
if (c>='0' && c<='9') {
v=c-'0';
} else if (c>='a' && c<='f') {
v=c-'a';
v+=10;
} else if (c>='A' && c<='F') {
v=c-'A';
v+=10;
} else {
ERR_PRINT("BUG");
v=0;
}
res<<=4;
res|=v;
}
idx+=4; //will add at the end anyway
} break;
//case '\"': res='\"'; break;
//case '\\': res='\\'; break;
//case '/': res='/'; break;
default: {
res = next;
//r_err_str="Invalid escape sequence";
//return ERR_PARSE_ERROR;
} break;
}
str+=res;
} else {
if (p_str[idx]=='\n')
line++;
str+=p_str[idx];
}
idx++;
}
r_token.type=TK_STRING;
r_token.value=str;
return OK;
} break;
default: {
if (p_str[idx]<=32) {
idx++;
break;
}
if (p_str[idx]=='-' || (p_str[idx]>='0' && p_str[idx]<='9')) {
//a number
const CharType *rptr;
double number = String::to_double(&p_str[idx],&rptr);
idx+=(rptr - &p_str[idx]);
r_token.type=TK_NUMBER;
r_token.value=number;
return OK;
} else if ((p_str[idx]>='A' && p_str[idx]<='Z') || (p_str[idx]>='a' && p_str[idx]<='z')) {
String id;
while((p_str[idx]>='A' && p_str[idx]<='Z') || (p_str[idx]>='a' && p_str[idx]<='z')) {
id+=p_str[idx];
idx++;
}
r_token.type=TK_IDENTIFIER;
r_token.value=id;
return OK;
} else {
r_err_str="Unexpected character.";
return ERR_PARSE_ERROR;
}
}
}
}
return ERR_PARSE_ERROR;
}
Error JSON::_parse_value(Variant &value,Token& token,const CharType *p_str,int &index, int p_len,int &line,String &r_err_str) {
if (token.type==TK_CURLY_BRACKET_OPEN) {
Dictionary d;
Error err = _parse_object(d,p_str,index,p_len,line,r_err_str);
if (err)
return err;
value=d;
return OK;
} else if (token.type==TK_BRACKET_OPEN) {
Array a;
Error err = _parse_array(a,p_str,index,p_len,line,r_err_str);
if (err)
return err;
value=a;
return OK;
} else if (token.type==TK_IDENTIFIER) {
String id = token.value;
if (id=="true")
value=true;
else if (id=="false")
value=false;
else if (id=="null")
value=Variant();
else {
r_err_str="Expected 'true','false' or 'null', got '"+id+"'.";
return ERR_PARSE_ERROR;
}
return OK;
} else if (token.type==TK_NUMBER) {
value=token.value;
return OK;
} else if (token.type==TK_STRING) {
value=token.value;
return OK;
} else {
r_err_str="Expected value, got "+String(tk_name[token.type])+".";
return ERR_PARSE_ERROR;
}
return ERR_PARSE_ERROR;
}
Error JSON::_parse_array(Array &array,const CharType *p_str,int &index, int p_len,int &line,String &r_err_str) {
Token token;
bool need_comma=false;
while(index<p_len) {
Error err = _get_token(p_str,index,p_len,token,line,r_err_str);
if (err!=OK)
return err;
if (token.type==TK_BRACKET_CLOSE) {
return OK;
}
if (need_comma) {
if (token.type!=TK_COMMA) {
r_err_str="Expected ','";
return ERR_PARSE_ERROR;
} else {
need_comma=false;
continue;
}
}
Variant v;
err = _parse_value(v,token,p_str,index,p_len,line,r_err_str);
if (err)
return err;
array.push_back(v);
need_comma=true;
}
return OK;
}
Error JSON::_parse_object(Dictionary &object,const CharType *p_str,int &index, int p_len,int &line,String &r_err_str) {
bool at_key=true;
String key;
Token token;
bool need_comma=false;
while(index<p_len) {
if (at_key) {
Error err = _get_token(p_str,index,p_len,token,line,r_err_str);
if (err!=OK)
return err;
if (token.type==TK_CURLY_BRACKET_CLOSE) {
return OK;
}
if (need_comma) {
if (token.type!=TK_COMMA) {
r_err_str="Expected '}' or ','";
return ERR_PARSE_ERROR;
} else {
need_comma=false;
continue;
}
}
if (token.type!=TK_STRING) {
r_err_str="Expected key";
return ERR_PARSE_ERROR;
}
key=token.value;
err = _get_token(p_str,index,p_len,token,line,r_err_str);
if (err!=OK)
return err;
if (token.type!=TK_COLON) {
r_err_str="Expected ':'";
return ERR_PARSE_ERROR;
}
at_key=false;
} else {
Error err = _get_token(p_str,index,p_len,token,line,r_err_str);
if (err!=OK)
return err;
Variant v;
err = _parse_value(v,token,p_str,index,p_len,line,r_err_str);
if (err)
return err;
object[key]=v;
need_comma=true;
at_key=true;
}
}
return OK;
}
Error JSON::parse(const String& p_json, Variant &r_ret, String &r_err_str, int &r_err_line) {
const CharType *str = p_json.ptr();
int idx = 0;
int len = p_json.length();
Token token;
r_err_line=0;
String aux_key;
Error err = _get_token(str,idx,len,token,r_err_line,r_err_str);
if (err)
return err;
err = _parse_value(r_ret,token,str,idx,len,r_err_line,r_err_str);
return err;
}