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785 lines
24 KiB
785 lines
24 KiB
6 years ago
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/* Copyright (c) 2013 Dropbox, Inc.
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "json11.hpp"
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#include <cassert>
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#include <cmath>
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#include <cstdlib>
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#include <cstdio>
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#include <limits>
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namespace json11 {
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static const int max_depth = 200;
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using std::string;
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using std::vector;
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using std::map;
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using std::make_shared;
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using std::initializer_list;
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using std::move;
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/* Helper for representing null - just a do-nothing struct, plus comparison
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* operators so the helpers in JsonValue work. We can't use nullptr_t because
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* it may not be orderable.
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*/
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struct NullStruct {
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bool operator==(NullStruct) const { return true; }
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bool operator<(NullStruct) const { return false; }
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};
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/* * * * * * * * * * * * * * * * * * * *
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* Serialization
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*/
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static void dump(NullStruct, string &out) {
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out += "null";
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}
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static void dump(double value, string &out) {
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if (std::isfinite(value)) {
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char buf[32];
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snprintf(buf, sizeof buf, "%.17g", value);
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out += buf;
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} else {
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out += "null";
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}
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}
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static void dump(int value, string &out) {
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char buf[32];
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snprintf(buf, sizeof buf, "%d", value);
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out += buf;
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}
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static void dump(bool value, string &out) {
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out += value ? "true" : "false";
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}
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static void dump(const string &value, string &out) {
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out += '"';
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for (size_t i = 0; i < value.length(); i++) {
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const char ch = value[i];
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if (ch == '\\') {
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out += "\\\\";
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} else if (ch == '"') {
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out += "\\\"";
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} else if (ch == '\b') {
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out += "\\b";
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} else if (ch == '\f') {
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out += "\\f";
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} else if (ch == '\n') {
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out += "\\n";
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} else if (ch == '\r') {
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out += "\\r";
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} else if (ch == '\t') {
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out += "\\t";
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} else if (static_cast<uint8_t>(ch) <= 0x1f) {
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char buf[8];
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snprintf(buf, sizeof buf, "\\u%04x", ch);
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out += buf;
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} else if (static_cast<uint8_t>(ch) == 0xe2 && static_cast<uint8_t>(value[i+1]) == 0x80
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&& static_cast<uint8_t>(value[i+2]) == 0xa8) {
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out += "\\u2028";
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i += 2;
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} else if (static_cast<uint8_t>(ch) == 0xe2 && static_cast<uint8_t>(value[i+1]) == 0x80
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&& static_cast<uint8_t>(value[i+2]) == 0xa9) {
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out += "\\u2029";
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i += 2;
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} else {
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out += ch;
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}
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}
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out += '"';
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}
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static void dump(const Json::array &values, string &out) {
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bool first = true;
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out += "[";
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for (const auto &value : values) {
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if (!first)
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out += ", ";
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value.dump(out);
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first = false;
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}
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out += "]";
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}
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static void dump(const Json::object &values, string &out) {
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bool first = true;
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out += "{";
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for (const auto &kv : values) {
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if (!first)
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out += ", ";
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dump(kv.first, out);
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out += ": ";
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kv.second.dump(out);
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first = false;
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}
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out += "}";
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}
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void Json::dump(string &out) const {
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m_ptr->dump(out);
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}
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/* * * * * * * * * * * * * * * * * * * *
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* Value wrappers
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*/
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template <Json::Type tag, typename T>
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class Value : public JsonValue {
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protected:
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// Constructors
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explicit Value(const T &value) : m_value(value) {}
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explicit Value(T &&value) : m_value(move(value)) {}
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// Get type tag
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Json::Type type() const override {
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return tag;
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}
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// Comparisons
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bool equals(const JsonValue * other) const override {
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return m_value == static_cast<const Value<tag, T> *>(other)->m_value;
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}
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bool less(const JsonValue * other) const override {
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return m_value < static_cast<const Value<tag, T> *>(other)->m_value;
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}
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const T m_value;
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void dump(string &out) const override { json11::dump(m_value, out); }
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};
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class JsonDouble final : public Value<Json::NUMBER, double> {
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double number_value() const override { return m_value; }
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int int_value() const override { return static_cast<int>(m_value); }
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bool equals(const JsonValue * other) const override { return m_value == other->number_value(); }
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bool less(const JsonValue * other) const override { return m_value < other->number_value(); }
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public:
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explicit JsonDouble(double value) : Value(value) {}
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};
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class JsonInt final : public Value<Json::NUMBER, int> {
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double number_value() const override { return m_value; }
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int int_value() const override { return m_value; }
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bool equals(const JsonValue * other) const override { return m_value == other->number_value(); }
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bool less(const JsonValue * other) const override { return m_value < other->number_value(); }
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public:
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explicit JsonInt(int value) : Value(value) {}
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};
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class JsonBoolean final : public Value<Json::BOOL, bool> {
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bool bool_value() const override { return m_value; }
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public:
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explicit JsonBoolean(bool value) : Value(value) {}
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};
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class JsonString final : public Value<Json::STRING, string> {
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const string &string_value() const override { return m_value; }
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public:
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explicit JsonString(const string &value) : Value(value) {}
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explicit JsonString(string &&value) : Value(move(value)) {}
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};
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class JsonArray final : public Value<Json::ARRAY, Json::array> {
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const Json::array &array_items() const override { return m_value; }
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const Json & operator[](size_t i) const override;
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public:
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explicit JsonArray(const Json::array &value) : Value(value) {}
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explicit JsonArray(Json::array &&value) : Value(move(value)) {}
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};
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class JsonObject final : public Value<Json::OBJECT, Json::object> {
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const Json::object &object_items() const override { return m_value; }
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const Json & operator[](const string &key) const override;
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public:
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explicit JsonObject(const Json::object &value) : Value(value) {}
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explicit JsonObject(Json::object &&value) : Value(move(value)) {}
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};
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class JsonNull final : public Value<Json::NUL, NullStruct> {
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public:
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JsonNull() : Value({}) {}
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};
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/* * * * * * * * * * * * * * * * * * * *
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* Static globals - static-init-safe
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*/
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struct Statics {
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const std::shared_ptr<JsonValue> null = make_shared<JsonNull>();
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const std::shared_ptr<JsonValue> t = make_shared<JsonBoolean>(true);
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const std::shared_ptr<JsonValue> f = make_shared<JsonBoolean>(false);
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const string empty_string;
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const vector<Json> empty_vector;
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const map<string, Json> empty_map;
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Statics() {}
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};
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static const Statics & statics() {
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static const Statics s {};
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return s;
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}
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static const Json & static_null() {
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// This has to be separate, not in Statics, because Json() accesses statics().null.
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static const Json json_null;
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return json_null;
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}
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/* * * * * * * * * * * * * * * * * * * *
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* Constructors
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*/
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Json::Json() noexcept : m_ptr(statics().null) {}
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Json::Json(std::nullptr_t) noexcept : m_ptr(statics().null) {}
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Json::Json(double value) : m_ptr(make_shared<JsonDouble>(value)) {}
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Json::Json(int value) : m_ptr(make_shared<JsonInt>(value)) {}
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Json::Json(bool value) : m_ptr(value ? statics().t : statics().f) {}
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Json::Json(const string &value) : m_ptr(make_shared<JsonString>(value)) {}
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Json::Json(string &&value) : m_ptr(make_shared<JsonString>(move(value))) {}
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Json::Json(const char * value) : m_ptr(make_shared<JsonString>(value)) {}
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Json::Json(const Json::array &values) : m_ptr(make_shared<JsonArray>(values)) {}
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Json::Json(Json::array &&values) : m_ptr(make_shared<JsonArray>(move(values))) {}
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Json::Json(const Json::object &values) : m_ptr(make_shared<JsonObject>(values)) {}
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Json::Json(Json::object &&values) : m_ptr(make_shared<JsonObject>(move(values))) {}
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/* * * * * * * * * * * * * * * * * * * *
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* Accessors
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*/
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Json::Type Json::type() const { return m_ptr->type(); }
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double Json::number_value() const { return m_ptr->number_value(); }
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int Json::int_value() const { return m_ptr->int_value(); }
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bool Json::bool_value() const { return m_ptr->bool_value(); }
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const string & Json::string_value() const { return m_ptr->string_value(); }
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const vector<Json> & Json::array_items() const { return m_ptr->array_items(); }
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const map<string, Json> & Json::object_items() const { return m_ptr->object_items(); }
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const Json & Json::operator[] (size_t i) const { return (*m_ptr)[i]; }
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const Json & Json::operator[] (const string &key) const { return (*m_ptr)[key]; }
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double JsonValue::number_value() const { return 0; }
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int JsonValue::int_value() const { return 0; }
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bool JsonValue::bool_value() const { return false; }
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const string & JsonValue::string_value() const { return statics().empty_string; }
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const vector<Json> & JsonValue::array_items() const { return statics().empty_vector; }
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const map<string, Json> & JsonValue::object_items() const { return statics().empty_map; }
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const Json & JsonValue::operator[] (size_t) const { return static_null(); }
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const Json & JsonValue::operator[] (const string &) const { return static_null(); }
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const Json & JsonObject::operator[] (const string &key) const {
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auto iter = m_value.find(key);
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return (iter == m_value.end()) ? static_null() : iter->second;
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}
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const Json & JsonArray::operator[] (size_t i) const {
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if (i >= m_value.size()) return static_null();
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else return m_value[i];
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}
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/* * * * * * * * * * * * * * * * * * * *
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* Comparison
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*/
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bool Json::operator== (const Json &other) const {
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if (m_ptr->type() != other.m_ptr->type())
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return false;
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return m_ptr->equals(other.m_ptr.get());
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}
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bool Json::operator< (const Json &other) const {
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if (m_ptr->type() != other.m_ptr->type())
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return m_ptr->type() < other.m_ptr->type();
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return m_ptr->less(other.m_ptr.get());
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}
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/* * * * * * * * * * * * * * * * * * * *
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* Parsing
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*/
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/* esc(c)
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*
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* Format char c suitable for printing in an error message.
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*/
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static inline string esc(char c) {
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char buf[12];
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if (static_cast<uint8_t>(c) >= 0x20 && static_cast<uint8_t>(c) <= 0x7f) {
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snprintf(buf, sizeof buf, "'%c' (%d)", c, c);
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} else {
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snprintf(buf, sizeof buf, "(%d)", c);
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}
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return string(buf);
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}
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static inline bool in_range(long x, long lower, long upper) {
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return (x >= lower && x <= upper);
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}
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namespace {
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/* JsonParser
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*
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* Object that tracks all state of an in-progress parse.
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*/
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struct JsonParser final {
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/* State
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*/
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const string &str;
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size_t i;
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string &err;
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bool failed;
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const JsonParse strategy;
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|
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/* fail(msg, err_ret = Json())
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*
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* Mark this parse as failed.
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||
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*/
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Json fail(string &&msg) {
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return fail(move(msg), Json());
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}
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template <typename T>
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|
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 (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() {
|
||
|
|
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<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++;
|
||
|
|
}
|
||
|
|
|
||
|
|
return std::strtod(str.c_str() + start_pos, nullptr);
|
||
|
|
}
|
||
|
|
|
||
|
|
/* 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
|