godot/core/io/json.cpp
Rémi Verschelde 1426cd3b3a
One Copyright Update to rule them all
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.

It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).

We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).

Also fixed "cf." Frenchism - it's meant as "refer to / see".

Backported from #70885.
2023-01-10 15:26:54 +01:00

481 lines
12 KiB
C++

/**************************************************************************/
/* json.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 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 "core/print_string.h"
const char *JSON::tk_name[TK_MAX] = {
"'{'",
"'}'",
"'['",
"']'",
"identifier",
"string",
"number",
"':'",
"','",
"EOF",
};
static String _make_indent(const String &p_indent, int p_size) {
String indent_text = "";
if (!p_indent.empty()) {
for (int i = 0; i < p_size; i++) {
indent_text += p_indent;
}
}
return indent_text;
}
String JSON::_print_var(const Variant &p_var, const String &p_indent, int p_cur_indent, bool p_sort_keys, Set<const void *> &p_markers) {
String colon = ":";
String end_statement = "";
if (!p_indent.empty()) {
colon += " ";
end_statement += "\n";
}
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 = "[";
s += end_statement;
Array a = p_var;
ERR_FAIL_COND_V_MSG(p_markers.has(a.id()), "\"[...]\"", "Converting circular structure to JSON.");
p_markers.insert(a.id());
for (int i = 0; i < a.size(); i++) {
if (i > 0) {
s += ",";
s += end_statement;
}
s += _make_indent(p_indent, p_cur_indent + 1) + _print_var(a[i], p_indent, p_cur_indent + 1, p_sort_keys, p_markers);
}
s += end_statement + _make_indent(p_indent, p_cur_indent) + "]";
p_markers.erase(a.id());
return s;
};
case Variant::DICTIONARY: {
String s = "{";
s += end_statement;
Dictionary d = p_var;
ERR_FAIL_COND_V_MSG(p_markers.has(d.id()), "\"{...}\"", "Converting circular structure to JSON.");
p_markers.insert(d.id());
List<Variant> keys;
d.get_key_list(&keys);
if (p_sort_keys) {
keys.sort();
}
for (List<Variant>::Element *E = keys.front(); E; E = E->next()) {
if (E != keys.front()) {
s += ",";
s += end_statement;
}
s += _make_indent(p_indent, p_cur_indent + 1) + _print_var(String(E->get()), p_indent, p_cur_indent + 1, p_sort_keys, p_markers);
s += colon;
s += _print_var(d[E->get()], p_indent, p_cur_indent + 1, p_sort_keys, p_markers);
}
s += end_statement + _make_indent(p_indent, p_cur_indent) + "}";
p_markers.erase(d.id());
return s;
};
default:
return "\"" + String(p_var).json_escape() + "\"";
}
}
String JSON::print(const Variant &p_var, const String &p_indent, bool p_sort_keys) {
Set<const void *> markers;
return _print_var(p_var, p_indent, 0, p_sort_keys, markers);
}
Error JSON::_get_token(const CharType *p_str, int &index, int p_len, Token &r_token, int &line, String &r_err_str) {
while (p_len > 0) {
switch (p_str[index]) {
case '\n': {
line++;
index++;
break;
};
case 0: {
r_token.type = TK_EOF;
return OK;
} break;
case '{': {
r_token.type = TK_CURLY_BRACKET_OPEN;
index++;
return OK;
};
case '}': {
r_token.type = TK_CURLY_BRACKET_CLOSE;
index++;
return OK;
};
case '[': {
r_token.type = TK_BRACKET_OPEN;
index++;
return OK;
};
case ']': {
r_token.type = TK_BRACKET_CLOSE;
index++;
return OK;
};
case ':': {
r_token.type = TK_COLON;
index++;
return OK;
};
case ',': {
r_token.type = TK_COMMA;
index++;
return OK;
};
case '"': {
index++;
String str;
while (true) {
if (p_str[index] == 0) {
r_err_str = "Unterminated String";
return ERR_PARSE_ERROR;
} else if (p_str[index] == '"') {
index++;
break;
} else if (p_str[index] == '\\') {
//escaped characters...
index++;
CharType next = p_str[index];
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[index + 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;
}
index += 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[index] == '\n') {
line++;
}
str += p_str[index];
}
index++;
}
r_token.type = TK_STRING;
r_token.value = str;
return OK;
} break;
default: {
if (p_str[index] <= 32) {
index++;
break;
}
if (p_str[index] == '-' || (p_str[index] >= '0' && p_str[index] <= '9')) {
//a number
const CharType *rptr;
double number = String::to_double(&p_str[index], &rptr);
index += (rptr - &p_str[index]);
r_token.type = TK_NUMBER;
r_token.value = number;
return OK;
} else if ((p_str[index] >= 'A' && p_str[index] <= 'Z') || (p_str[index] >= 'a' && p_str[index] <= 'z')) {
String id;
while ((p_str[index] >= 'A' && p_str[index] <= 'Z') || (p_str[index] >= 'a' && p_str[index] <= 'z')) {
id += p_str[index];
index++;
}
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;
} 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;
} 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;
}
} else if (token.type == TK_NUMBER) {
value = token.value;
} else if (token.type == TK_STRING) {
value = token.value;
} else {
r_err_str = "Expected value, got " + String(tk_name[token.type]) + ".";
return ERR_PARSE_ERROR;
}
return OK;
}
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;
}
r_err_str = "Expected ']'";
return ERR_PARSE_ERROR;
}
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;
}
}
r_err_str = "Expected '}'";
return ERR_PARSE_ERROR;
}
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);
// Check if EOF is reached
// or it's a type of the next token.
if (err == OK && idx < len) {
err = _get_token(str, idx, len, token, r_err_line, r_err_str);
if (err || token.type != TK_EOF) {
r_err_str = "Expected 'EOF'";
// Reset return value to empty `Variant`
r_ret = Variant();
return ERR_PARSE_ERROR;
}
}
return err;
}