1011 lines
27 KiB
C++
1011 lines
27 KiB
C++
/* Copyright (c) 2013 Dropbox, Inc.
|
|
*
|
|
* 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 "json11.hpp"
|
|
#include <cassert>
|
|
#include <cmath>
|
|
#include <cstdio>
|
|
#include <cstdlib>
|
|
#include <limits>
|
|
#include <locale>
|
|
#include <sstream>
|
|
|
|
namespace json11
|
|
{
|
|
|
|
static const int max_depth = 200;
|
|
|
|
using std::initializer_list;
|
|
using std::make_shared;
|
|
using std::map;
|
|
using std::move;
|
|
using std::string;
|
|
using std::vector;
|
|
|
|
/* Helper for representing null - just a do-nothing struct, plus comparison
|
|
* operators so the helpers in JsonValue work. We can't use nullptr_t because
|
|
* it may not be orderable.
|
|
*/
|
|
struct NullStruct
|
|
{
|
|
bool operator==(NullStruct) const { return true; }
|
|
bool operator<(NullStruct) const { return false; }
|
|
};
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Serialization
|
|
*/
|
|
|
|
static void dump(NullStruct, string& out)
|
|
{
|
|
out += "null";
|
|
}
|
|
|
|
static void dump(double value, string& out)
|
|
{
|
|
if (std::isfinite(value))
|
|
{
|
|
std::ostringstream stm;
|
|
stm.imbue(std::locale("C"));
|
|
stm << value;
|
|
out += stm.str();
|
|
}
|
|
else
|
|
{
|
|
out += "null";
|
|
}
|
|
}
|
|
|
|
static void dump(int value, string& out)
|
|
{
|
|
char buf[32];
|
|
snprintf(buf, sizeof buf, "%d", value);
|
|
out += buf;
|
|
}
|
|
|
|
static void dump(bool value, string& out)
|
|
{
|
|
out += value ? "true" : "false";
|
|
}
|
|
|
|
static void dump(const string& value, string& out)
|
|
{
|
|
out += '"';
|
|
for (std::size_t i = 0; i < value.length(); i++)
|
|
{
|
|
const char ch = value[i];
|
|
if (ch == '\\')
|
|
{
|
|
out += "\\\\";
|
|
}
|
|
else if (ch == '"')
|
|
{
|
|
out += "\\\"";
|
|
}
|
|
else if (ch == '\b')
|
|
{
|
|
out += "\\b";
|
|
}
|
|
else if (ch == '\f')
|
|
{
|
|
out += "\\f";
|
|
}
|
|
else if (ch == '\n')
|
|
{
|
|
out += "\\n";
|
|
}
|
|
else if (ch == '\r')
|
|
{
|
|
out += "\\r";
|
|
}
|
|
else if (ch == '\t')
|
|
{
|
|
out += "\\t";
|
|
}
|
|
else if (static_cast<std::uint8_t>(ch) <= 0x1f)
|
|
{
|
|
char buf[8];
|
|
snprintf(buf, sizeof buf, "\\u%04x", ch);
|
|
out += buf;
|
|
}
|
|
else if (static_cast<std::uint8_t>(ch) == 0xe2 && static_cast<std::uint8_t>(value[i + 1]) == 0x80
|
|
&& static_cast<std::uint8_t>(value[i + 2]) == 0xa8)
|
|
{
|
|
out += "\\u2028";
|
|
i += 2;
|
|
}
|
|
else if (static_cast<std::uint8_t>(ch) == 0xe2 && static_cast<std::uint8_t>(value[i + 1]) == 0x80
|
|
&& static_cast<std::uint8_t>(value[i + 2]) == 0xa9)
|
|
{
|
|
out += "\\u2029";
|
|
i += 2;
|
|
}
|
|
else
|
|
{
|
|
out += ch;
|
|
}
|
|
}
|
|
out += '"';
|
|
}
|
|
|
|
static void dump(const Json::array& values, string& out)
|
|
{
|
|
bool first = true;
|
|
out += "[";
|
|
for (const auto& value : values)
|
|
{
|
|
if (!first)
|
|
out += ", ";
|
|
value.dump(out);
|
|
first = false;
|
|
}
|
|
out += "]";
|
|
}
|
|
|
|
static void dump(const Json::object& values, string& out)
|
|
{
|
|
bool first = true;
|
|
out += "{";
|
|
for (const auto& kv : values)
|
|
{
|
|
if (!first)
|
|
out += ", ";
|
|
dump(kv.first, out);
|
|
out += ": ";
|
|
kv.second.dump(out);
|
|
first = false;
|
|
}
|
|
out += "}";
|
|
}
|
|
|
|
void Json::dump(string& out) const
|
|
{
|
|
m_ptr->dump(out);
|
|
}
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Value wrappers
|
|
*/
|
|
|
|
template <Json::Type tag, typename T>
|
|
class Value : public JsonValue
|
|
{
|
|
protected:
|
|
// Constructors
|
|
explicit Value(const T& value)
|
|
: m_value(value)
|
|
{
|
|
}
|
|
explicit Value(T&& value)
|
|
: m_value(move(value))
|
|
{
|
|
}
|
|
|
|
// Get type tag
|
|
Json::Type type() const override
|
|
{
|
|
return tag;
|
|
}
|
|
|
|
// Comparisons
|
|
bool equals(const JsonValue* other) const override
|
|
{
|
|
return m_value == static_cast<const Value<tag, T>*>(other)->m_value;
|
|
}
|
|
bool less(const JsonValue* other) const override
|
|
{
|
|
return m_value < static_cast<const Value<tag, T>*>(other)->m_value;
|
|
}
|
|
|
|
const T m_value;
|
|
void dump(string& out) const override { json11::dump(m_value, out); }
|
|
};
|
|
|
|
class JsonDouble final : public Value<Json::NUMBER, double>
|
|
{
|
|
double number_value() const override { return m_value; }
|
|
int int_value() const override { return static_cast<int>(m_value); }
|
|
bool equals(const JsonValue* other) const override { return m_value == other->number_value(); }
|
|
bool less(const JsonValue* other) const override { return m_value < other->number_value(); }
|
|
|
|
public:
|
|
explicit JsonDouble(double value)
|
|
: Value(value)
|
|
{
|
|
}
|
|
};
|
|
|
|
class JsonInt final : public Value<Json::NUMBER, int>
|
|
{
|
|
double number_value() const override { return m_value; }
|
|
int int_value() const override { return m_value; }
|
|
bool equals(const JsonValue* other) const override { return m_value == other->number_value(); }
|
|
bool less(const JsonValue* other) const override { return m_value < other->number_value(); }
|
|
|
|
public:
|
|
explicit JsonInt(int value)
|
|
: Value(value)
|
|
{
|
|
}
|
|
};
|
|
|
|
class JsonBoolean final : public Value<Json::BOOL, bool>
|
|
{
|
|
bool bool_value() const override { return m_value; }
|
|
|
|
public:
|
|
explicit JsonBoolean(bool value)
|
|
: Value(value)
|
|
{
|
|
}
|
|
};
|
|
|
|
class JsonString final : public Value<Json::STRING, string>
|
|
{
|
|
const string& string_value() const override { return m_value; }
|
|
|
|
public:
|
|
explicit JsonString(const string& value)
|
|
: Value(value)
|
|
{
|
|
}
|
|
explicit JsonString(string&& value)
|
|
: Value(move(value))
|
|
{
|
|
}
|
|
};
|
|
|
|
class JsonArray final : public Value<Json::ARRAY, Json::array>
|
|
{
|
|
const Json::array& array_items() const override { return m_value; }
|
|
const Json& operator[](std::size_t i) const override;
|
|
|
|
public:
|
|
explicit JsonArray(const Json::array& value)
|
|
: Value(value)
|
|
{
|
|
}
|
|
explicit JsonArray(Json::array&& value)
|
|
: Value(move(value))
|
|
{
|
|
}
|
|
};
|
|
|
|
class JsonObject final : public Value<Json::OBJECT, Json::object>
|
|
{
|
|
const Json::object& object_items() const override { return m_value; }
|
|
const Json& operator[](const string& key) const override;
|
|
|
|
public:
|
|
explicit JsonObject(const Json::object& value)
|
|
: Value(value)
|
|
{
|
|
}
|
|
explicit JsonObject(Json::object&& value)
|
|
: Value(move(value))
|
|
{
|
|
}
|
|
};
|
|
|
|
class JsonNull final : public Value<Json::NUL, NullStruct>
|
|
{
|
|
public:
|
|
JsonNull()
|
|
: Value({})
|
|
{
|
|
}
|
|
};
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Static globals - static-init-safe
|
|
*/
|
|
struct Statics
|
|
{
|
|
const std::shared_ptr<JsonValue> null = make_shared<JsonNull>();
|
|
const std::shared_ptr<JsonValue> t = make_shared<JsonBoolean>(true);
|
|
const std::shared_ptr<JsonValue> f = make_shared<JsonBoolean>(false);
|
|
const string empty_string;
|
|
const vector<Json> empty_vector;
|
|
const map<string, Json> empty_map;
|
|
Statics() {}
|
|
};
|
|
|
|
static const Statics& statics()
|
|
{
|
|
static const Statics s {};
|
|
return s;
|
|
}
|
|
|
|
static const Json& static_null()
|
|
{
|
|
// This has to be separate, not in Statics, because Json() accesses statics().null.
|
|
static const Json json_null;
|
|
return json_null;
|
|
}
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Constructors
|
|
*/
|
|
|
|
Json::Json() noexcept
|
|
: m_ptr(statics().null)
|
|
{
|
|
}
|
|
Json::Json(std::nullptr_t) noexcept
|
|
: m_ptr(statics().null)
|
|
{
|
|
}
|
|
Json::Json(double value)
|
|
: m_ptr(make_shared<JsonDouble>(value))
|
|
{
|
|
}
|
|
Json::Json(int value)
|
|
: m_ptr(make_shared<JsonInt>(value))
|
|
{
|
|
}
|
|
Json::Json(bool value)
|
|
: m_ptr(value ? statics().t : statics().f)
|
|
{
|
|
}
|
|
Json::Json(const string& value)
|
|
: m_ptr(make_shared<JsonString>(value))
|
|
{
|
|
}
|
|
Json::Json(string&& value)
|
|
: m_ptr(make_shared<JsonString>(move(value)))
|
|
{
|
|
}
|
|
Json::Json(const char* value)
|
|
: m_ptr(make_shared<JsonString>(value))
|
|
{
|
|
}
|
|
Json::Json(const Json::array& values)
|
|
: m_ptr(make_shared<JsonArray>(values))
|
|
{
|
|
}
|
|
Json::Json(Json::array&& values)
|
|
: m_ptr(make_shared<JsonArray>(move(values)))
|
|
{
|
|
}
|
|
Json::Json(const Json::object& values)
|
|
: m_ptr(make_shared<JsonObject>(values))
|
|
{
|
|
}
|
|
Json::Json(Json::object&& values)
|
|
: m_ptr(make_shared<JsonObject>(move(values)))
|
|
{
|
|
}
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Accessors
|
|
*/
|
|
|
|
Json::Type Json::type() const { return m_ptr->type(); }
|
|
double Json::number_value() const { return m_ptr->number_value(); }
|
|
int Json::int_value() const { return m_ptr->int_value(); }
|
|
bool Json::bool_value() const { return m_ptr->bool_value(); }
|
|
const string& Json::string_value() const { return m_ptr->string_value(); }
|
|
const vector<Json>& Json::array_items() const { return m_ptr->array_items(); }
|
|
const map<string, Json>& Json::object_items() const { return m_ptr->object_items(); }
|
|
const Json& Json::operator[](std::size_t i) const { return (*m_ptr)[i]; }
|
|
const Json& Json::operator[](const string& key) const { return (*m_ptr)[key]; }
|
|
|
|
double JsonValue::number_value() const { return 0; }
|
|
int JsonValue::int_value() const { return 0; }
|
|
bool JsonValue::bool_value() const { return false; }
|
|
const string& JsonValue::string_value() const { return statics().empty_string; }
|
|
const vector<Json>& JsonValue::array_items() const { return statics().empty_vector; }
|
|
const map<string, Json>& JsonValue::object_items() const { return statics().empty_map; }
|
|
const Json& JsonValue::operator[](std::size_t) const { return static_null(); }
|
|
const Json& JsonValue::operator[](const string&) const { return static_null(); }
|
|
|
|
const Json& JsonObject::operator[](const string& key) const
|
|
{
|
|
auto iter = m_value.find(key);
|
|
return (iter == m_value.end()) ? static_null() : iter->second;
|
|
}
|
|
const Json& JsonArray::operator[](std::size_t i) const
|
|
{
|
|
if (i >= m_value.size())
|
|
return static_null();
|
|
else
|
|
return m_value[i];
|
|
}
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Comparison
|
|
*/
|
|
|
|
bool Json::operator==(const Json& other) const
|
|
{
|
|
if (m_ptr == other.m_ptr)
|
|
return true;
|
|
if (m_ptr->type() != other.m_ptr->type())
|
|
return false;
|
|
|
|
return m_ptr->equals(other.m_ptr.get());
|
|
}
|
|
|
|
bool Json::operator<(const Json& other) const
|
|
{
|
|
if (m_ptr == other.m_ptr)
|
|
return false;
|
|
if (m_ptr->type() != other.m_ptr->type())
|
|
return m_ptr->type() < other.m_ptr->type();
|
|
|
|
return m_ptr->less(other.m_ptr.get());
|
|
}
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Parsing
|
|
*/
|
|
|
|
/* esc(c)
|
|
*
|
|
* Format char c suitable for printing in an error message.
|
|
*/
|
|
static inline string esc(char c)
|
|
{
|
|
char buf[12];
|
|
if (static_cast<std::uint8_t>(c) >= 0x20 && static_cast<std::uint8_t>(c) <= 0x7f)
|
|
{
|
|
snprintf(buf, sizeof buf, "'%c' (%d)", c, c);
|
|
}
|
|
else
|
|
{
|
|
snprintf(buf, sizeof buf, "(%d)", c);
|
|
}
|
|
return string(buf);
|
|
}
|
|
|
|
static inline bool in_range(long x, long lower, long upper)
|
|
{
|
|
return (x >= lower && x <= upper);
|
|
}
|
|
|
|
namespace
|
|
{
|
|
/* JsonParser
|
|
*
|
|
* Object that tracks all state of an in-progress parse.
|
|
*/
|
|
struct JsonParser final
|
|
{
|
|
|
|
/* State
|
|
*/
|
|
const string& str;
|
|
std::size_t i;
|
|
string& err;
|
|
bool failed;
|
|
const JsonParse strategy;
|
|
|
|
/* fail(msg, err_ret = Json())
|
|
*
|
|
* Mark this parse as failed.
|
|
*/
|
|
Json fail(string&& msg)
|
|
{
|
|
return fail(move(msg), Json());
|
|
}
|
|
|
|
template <typename T>
|
|
T fail(string&& msg, const T err_ret)
|
|
{
|
|
if (!failed)
|
|
err = std::move(msg);
|
|
failed = true;
|
|
return err_ret;
|
|
}
|
|
|
|
/* consume_whitespace()
|
|
*
|
|
* Advance until the current character is non-whitespace.
|
|
*/
|
|
void consume_whitespace()
|
|
{
|
|
while (str[i] == ' ' || str[i] == '\r' || str[i] == '\n' || str[i] == '\t')
|
|
i++;
|
|
}
|
|
|
|
/* consume_comment()
|
|
*
|
|
* Advance comments (c-style inline and multiline).
|
|
*/
|
|
bool consume_comment()
|
|
{
|
|
bool comment_found = false;
|
|
if (str[i] == '/')
|
|
{
|
|
i++;
|
|
if (i == str.size())
|
|
return fail("unexpected end of input after start of comment", false);
|
|
if (str[i] == '/')
|
|
{ // inline comment
|
|
i++;
|
|
// advance until next line, or end of input
|
|
while (i < str.size() && str[i] != '\n')
|
|
{
|
|
i++;
|
|
}
|
|
comment_found = true;
|
|
}
|
|
else if (str[i] == '*')
|
|
{ // multiline comment
|
|
i++;
|
|
if (i > str.size() - 2)
|
|
return fail("unexpected end of input inside multi-line comment", false);
|
|
// advance until closing tokens
|
|
while (!(str[i] == '*' && str[i + 1] == '/'))
|
|
{
|
|
i++;
|
|
if (i > str.size() - 2)
|
|
return fail(
|
|
"unexpected end of input inside multi-line comment", false);
|
|
}
|
|
i += 2;
|
|
comment_found = true;
|
|
}
|
|
else
|
|
return fail("malformed comment", false);
|
|
}
|
|
return comment_found;
|
|
}
|
|
|
|
/* consume_garbage()
|
|
*
|
|
* Advance until the current character is non-whitespace and non-comment.
|
|
*/
|
|
void consume_garbage()
|
|
{
|
|
consume_whitespace();
|
|
if (strategy == JsonParse::COMMENTS)
|
|
{
|
|
bool comment_found = false;
|
|
do
|
|
{
|
|
comment_found = consume_comment();
|
|
if (failed)
|
|
return;
|
|
consume_whitespace();
|
|
} while (comment_found);
|
|
}
|
|
}
|
|
|
|
/* get_next_token()
|
|
*
|
|
* Return the next non-whitespace character. If the end of the input is reached,
|
|
* flag an error and return 0.
|
|
*/
|
|
char get_next_token()
|
|
{
|
|
consume_garbage();
|
|
if (failed)
|
|
return (char)0;
|
|
if (i == str.size())
|
|
return fail("unexpected end of input", (char)0);
|
|
|
|
return str[i++];
|
|
}
|
|
|
|
/* encode_utf8(pt, out)
|
|
*
|
|
* Encode pt as UTF-8 and add it to out.
|
|
*/
|
|
void encode_utf8(long pt, string& out)
|
|
{
|
|
if (pt < 0)
|
|
return;
|
|
|
|
if (pt < 0x80)
|
|
{
|
|
out += static_cast<char>(pt);
|
|
}
|
|
else if (pt < 0x800)
|
|
{
|
|
out += static_cast<char>((pt >> 6) | 0xC0);
|
|
out += static_cast<char>((pt & 0x3F) | 0x80);
|
|
}
|
|
else if (pt < 0x10000)
|
|
{
|
|
out += static_cast<char>((pt >> 12) | 0xE0);
|
|
out += static_cast<char>(((pt >> 6) & 0x3F) | 0x80);
|
|
out += static_cast<char>((pt & 0x3F) | 0x80);
|
|
}
|
|
else
|
|
{
|
|
out += static_cast<char>((pt >> 18) | 0xF0);
|
|
out += static_cast<char>(((pt >> 12) & 0x3F) | 0x80);
|
|
out += static_cast<char>(((pt >> 6) & 0x3F) | 0x80);
|
|
out += static_cast<char>((pt & 0x3F) | 0x80);
|
|
}
|
|
}
|
|
|
|
/* parse_string()
|
|
*
|
|
* Parse a string, starting at the current position.
|
|
*/
|
|
string parse_string()
|
|
{
|
|
string out;
|
|
long last_escaped_codepoint = -1;
|
|
while (true)
|
|
{
|
|
if (i == str.size())
|
|
return fail("unexpected end of input in string", "");
|
|
|
|
char ch = str[i++];
|
|
|
|
if (ch == '"')
|
|
{
|
|
encode_utf8(last_escaped_codepoint, out);
|
|
return out;
|
|
}
|
|
|
|
if (in_range(ch, 0, 0x1f))
|
|
return fail("unescaped " + esc(ch) + " in string", "");
|
|
|
|
// The usual case: non-escaped characters
|
|
if (ch != '\\')
|
|
{
|
|
encode_utf8(last_escaped_codepoint, out);
|
|
last_escaped_codepoint = -1;
|
|
out += ch;
|
|
continue;
|
|
}
|
|
|
|
// Handle escapes
|
|
if (i == str.size())
|
|
return fail("unexpected end of input in string", "");
|
|
|
|
ch = str[i++];
|
|
|
|
if (ch == 'u')
|
|
{
|
|
// Extract 4-byte escape sequence
|
|
string esc = str.substr(i, 4);
|
|
// Explicitly check length of the substring. The following loop
|
|
// relies on std::string returning the terminating NUL when
|
|
// accessing str[length]. Checking here reduces brittleness.
|
|
if (esc.length() < 4)
|
|
{
|
|
return fail("bad \\u escape: " + esc, "");
|
|
}
|
|
for (std::size_t j = 0; j < 4; j++)
|
|
{
|
|
if (!in_range(esc[j], 'a', 'f') && !in_range(esc[j], 'A', 'F')
|
|
&& !in_range(esc[j], '0', '9'))
|
|
return fail("bad \\u escape: " + esc, "");
|
|
}
|
|
|
|
long codepoint = strtol(esc.data(), nullptr, 16);
|
|
|
|
// JSON specifies that characters outside the BMP shall be encoded as a pair
|
|
// of 4-hex-digit \u escapes encoding their surrogate pair components. Check
|
|
// whether we're in the middle of such a beast: the previous codepoint was an
|
|
// escaped lead (high) surrogate, and this is a trail (low) surrogate.
|
|
if (in_range(last_escaped_codepoint, 0xD800, 0xDBFF)
|
|
&& in_range(codepoint, 0xDC00, 0xDFFF))
|
|
{
|
|
// Reassemble the two surrogate pairs into one astral-plane character, per
|
|
// the UTF-16 algorithm.
|
|
encode_utf8((((last_escaped_codepoint - 0xD800) << 10)
|
|
| (codepoint - 0xDC00))
|
|
+ 0x10000,
|
|
out);
|
|
last_escaped_codepoint = -1;
|
|
}
|
|
else
|
|
{
|
|
encode_utf8(last_escaped_codepoint, out);
|
|
last_escaped_codepoint = codepoint;
|
|
}
|
|
|
|
i += 4;
|
|
continue;
|
|
}
|
|
|
|
encode_utf8(last_escaped_codepoint, out);
|
|
last_escaped_codepoint = -1;
|
|
|
|
if (ch == 'b')
|
|
{
|
|
out += '\b';
|
|
}
|
|
else if (ch == 'f')
|
|
{
|
|
out += '\f';
|
|
}
|
|
else if (ch == 'n')
|
|
{
|
|
out += '\n';
|
|
}
|
|
else if (ch == 'r')
|
|
{
|
|
out += '\r';
|
|
}
|
|
else if (ch == 't')
|
|
{
|
|
out += '\t';
|
|
}
|
|
else if (ch == '"' || ch == '\\' || ch == '/')
|
|
{
|
|
out += ch;
|
|
}
|
|
else
|
|
{
|
|
return fail("invalid escape character " + esc(ch), "");
|
|
}
|
|
}
|
|
}
|
|
|
|
/* parse_number()
|
|
*
|
|
* Parse a double.
|
|
*/
|
|
Json parse_number()
|
|
{
|
|
std::size_t start_pos = i;
|
|
|
|
if (str[i] == '-')
|
|
i++;
|
|
|
|
// Integer part
|
|
if (str[i] == '0')
|
|
{
|
|
i++;
|
|
if (in_range(str[i], '0', '9'))
|
|
return fail("leading 0s not permitted in numbers");
|
|
}
|
|
else if (in_range(str[i], '1', '9'))
|
|
{
|
|
i++;
|
|
while (in_range(str[i], '0', '9'))
|
|
i++;
|
|
}
|
|
else
|
|
{
|
|
return fail("invalid " + esc(str[i]) + " in number");
|
|
}
|
|
|
|
if (str[i] != '.' && str[i] != 'e' && str[i] != 'E'
|
|
&& (i - start_pos) <= static_cast<std::size_t>(std::numeric_limits<int>::digits10))
|
|
{
|
|
return std::atoi(str.c_str() + start_pos);
|
|
}
|
|
|
|
// Decimal part
|
|
if (str[i] == '.')
|
|
{
|
|
i++;
|
|
if (!in_range(str[i], '0', '9'))
|
|
return fail("at least one digit required in fractional part");
|
|
|
|
while (in_range(str[i], '0', '9'))
|
|
i++;
|
|
}
|
|
|
|
// Exponent part
|
|
if (str[i] == 'e' || str[i] == 'E')
|
|
{
|
|
i++;
|
|
|
|
if (str[i] == '+' || str[i] == '-')
|
|
i++;
|
|
|
|
if (!in_range(str[i], '0', '9'))
|
|
return fail("at least one digit required in exponent");
|
|
|
|
while (in_range(str[i], '0', '9'))
|
|
i++;
|
|
}
|
|
|
|
std::istringstream stm(std::string(str.begin() + start_pos, str.end()));
|
|
stm.imbue(std::locale("C"));
|
|
double result;
|
|
stm >> result;
|
|
return result;
|
|
}
|
|
|
|
/* expect(str, res)
|
|
*
|
|
* Expect that 'str' starts at the character that was just read. If it does, advance
|
|
* the input and return res. If not, flag an error.
|
|
*/
|
|
Json expect(const string& expected, Json res)
|
|
{
|
|
assert(i != 0);
|
|
i--;
|
|
if (str.compare(i, expected.length(), expected) == 0)
|
|
{
|
|
i += expected.length();
|
|
return res;
|
|
}
|
|
else
|
|
{
|
|
return fail("parse error: expected " + expected + ", got " + str.substr(i, expected.length()));
|
|
}
|
|
}
|
|
|
|
/* parse_json()
|
|
*
|
|
* Parse a JSON object.
|
|
*/
|
|
Json parse_json(int depth)
|
|
{
|
|
if (depth > max_depth)
|
|
{
|
|
return fail("exceeded maximum nesting depth");
|
|
}
|
|
|
|
char ch = get_next_token();
|
|
if (failed)
|
|
return Json();
|
|
|
|
if (ch == '-' || (ch >= '0' && ch <= '9'))
|
|
{
|
|
i--;
|
|
return parse_number();
|
|
}
|
|
|
|
if (ch == 't')
|
|
return expect("true", true);
|
|
|
|
if (ch == 'f')
|
|
return expect("false", false);
|
|
|
|
if (ch == 'n')
|
|
return expect("null", Json());
|
|
|
|
if (ch == '"')
|
|
return parse_string();
|
|
|
|
if (ch == '{')
|
|
{
|
|
map<string, Json> data;
|
|
ch = get_next_token();
|
|
if (ch == '}')
|
|
return data;
|
|
|
|
while (1)
|
|
{
|
|
if (ch != '"')
|
|
return fail("expected '\"' in object, got " + esc(ch));
|
|
|
|
string key = parse_string();
|
|
if (failed)
|
|
return Json();
|
|
|
|
ch = get_next_token();
|
|
if (ch != ':')
|
|
return fail("expected ':' in object, got " + esc(ch));
|
|
|
|
data[std::move(key)] = parse_json(depth + 1);
|
|
if (failed)
|
|
return Json();
|
|
|
|
ch = get_next_token();
|
|
if (ch == '}')
|
|
break;
|
|
if (ch != ',')
|
|
return fail("expected ',' in object, got " + esc(ch));
|
|
|
|
ch = get_next_token();
|
|
}
|
|
return data;
|
|
}
|
|
|
|
if (ch == '[')
|
|
{
|
|
vector<Json> data;
|
|
ch = get_next_token();
|
|
if (ch == ']')
|
|
return data;
|
|
|
|
while (1)
|
|
{
|
|
i--;
|
|
data.push_back(parse_json(depth + 1));
|
|
if (failed)
|
|
return Json();
|
|
|
|
ch = get_next_token();
|
|
if (ch == ']')
|
|
break;
|
|
if (ch != ',')
|
|
return fail("expected ',' in list, got " + esc(ch));
|
|
|
|
ch = get_next_token();
|
|
(void)ch;
|
|
}
|
|
return data;
|
|
}
|
|
|
|
return fail("expected value, got " + esc(ch));
|
|
}
|
|
};
|
|
} //namespace {
|
|
|
|
Json Json::parse(const string& in, string& err, JsonParse strategy)
|
|
{
|
|
JsonParser parser {in, 0, err, false, strategy};
|
|
Json result = parser.parse_json(0);
|
|
|
|
// Check for any trailing garbage
|
|
parser.consume_garbage();
|
|
if (parser.failed)
|
|
return Json();
|
|
if (parser.i != in.size())
|
|
return parser.fail("unexpected trailing " + esc(in[parser.i]));
|
|
|
|
return result;
|
|
}
|
|
|
|
// Documented in json11.hpp
|
|
vector<Json> Json::parse_multi(const string& in,
|
|
std::string::size_type& parser_stop_pos,
|
|
string& err,
|
|
JsonParse strategy)
|
|
{
|
|
JsonParser parser {in, 0, err, false, strategy};
|
|
parser_stop_pos = 0;
|
|
vector<Json> json_vec;
|
|
while (parser.i != in.size() && !parser.failed)
|
|
{
|
|
json_vec.push_back(parser.parse_json(0));
|
|
if (parser.failed)
|
|
break;
|
|
|
|
// Check for another object
|
|
parser.consume_garbage();
|
|
if (parser.failed)
|
|
break;
|
|
parser_stop_pos = parser.i;
|
|
}
|
|
return json_vec;
|
|
}
|
|
|
|
/* * * * * * * * * * * * * * * * * * * *
|
|
* Shape-checking
|
|
*/
|
|
|
|
bool Json::has_shape(const shape& types, string& err) const
|
|
{
|
|
if (!is_object())
|
|
{
|
|
err = "expected JSON object, got " + dump();
|
|
return false;
|
|
}
|
|
|
|
for (auto& item : types)
|
|
{
|
|
if ((*this)[item.first].type() != item.second)
|
|
{
|
|
err = "bad type for " + item.first + " in " + dump();
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
} // namespace json11
|