outman/jsoncpp
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
2d55c7445f
jsoncpp/src/lib_json/json_reader.cpp
Tero Kinnunen 2d55c7445f
Parse large floats as infinity (#1349) (#1353) 
Return 1.9.1 functionality where values too large to fit in
double are converted to positive or negative infinity.

Commit 645cd04 changed functionality so that large floats cause
parse error, while version 1.9.1 accepted them as infinite.
This is problematic because writer outputs infinity values
as `1e+9999`, which could no longer be parsed back.

Fixed also legacy Reader even though it did not parse large values
even before breaking change, due to problematic output/parse asymmetry.

`>>` operator sets value to numeric_limits::max/lowest value if
representation is too large to fit to double. [1][2] In macos
value appears to be parsed to infinity.

> | value in *val*           | description |
> |--------------------------|-------------|
> | numeric_limits::max()    | The sequence represents a value too large for the type of val |
> | numeric_limits::lowest() | The sequence represents a value too large negative for the type of val |

[1] https://www.cplusplus.com/reference/istream/istream/operator%3E%3E/
[2] https://www.cplusplus.com/reference/locale/num_get/get/

Signed-off-by: Tero Kinnunen <tero.kinnunen@vaisala.com>

Co-authored-by: Tero Kinnunen <tero.kinnunen@vaisala.com>
2021-12-14 18:00:28 -08:00

2005 lines
57 KiB
C++
Raw Blame History

// Copyright 2007-2011 Baptiste Lepilleur and The JsonCpp Authors
// Copyright (C) 2016 InfoTeCS JSC. All rights reserved.
// Distributed under MIT license, or public domain if desired and
// recognized in your jurisdiction.
// See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
#if !defined(JSON_IS_AMALGAMATION)
#include "json_tool.h"
#include <json/assertions.h>
#include <json/reader.h>
#include <json/value.h>
#endif // if !defined(JSON_IS_AMALGAMATION)
#include <algorithm>
#include <cassert>
#include <cmath>
#include <cstring>
#include <iostream>
#include <istream>
#include <limits>
#include <memory>
#include <set>
#include <sstream>
#include <utility>
#include <cstdio>
#if __cplusplus >= 201103L
#if !defined(sscanf)
#define sscanf std::sscanf
#endif
#endif //__cplusplus
#if defined(_MSC_VER)
#if !defined(_CRT_SECURE_CPP_OVERLOAD_STANDARD_NAMES)
#define _CRT_SECURE_CPP_OVERLOAD_STANDARD_NAMES 1
#endif //_CRT_SECURE_CPP_OVERLOAD_STANDARD_NAMES
#endif //_MSC_VER
#if defined(_MSC_VER)
// Disable warning about strdup being deprecated.
#pragma warning(disable : 4996)
#endif
// Define JSONCPP_DEPRECATED_STACK_LIMIT as an appropriate integer at compile
// time to change the stack limit
#if !defined(JSONCPP_DEPRECATED_STACK_LIMIT)
#define JSONCPP_DEPRECATED_STACK_LIMIT 1000
#endif
static size_t const stackLimit_g =
JSONCPP_DEPRECATED_STACK_LIMIT; // see readValue()
namespace Json {
#if __cplusplus >= 201103L || (defined(_CPPLIB_VER) && _CPPLIB_VER >= 520)
using CharReaderPtr = std::unique_ptr<CharReader>;
#else
using CharReaderPtr = std::auto_ptr<CharReader>;
#endif
// Implementation of class Features
// ////////////////////////////////
Features::Features() = default;
Features Features::all() { return {}; }
Features Features::strictMode() {
Features features;
features.allowComments_ = false;
features.strictRoot_ = true;
features.allowDroppedNullPlaceholders_ = false;
features.allowNumericKeys_ = false;
return features;
}
// Implementation of class Reader
// ////////////////////////////////
bool Reader::containsNewLine(Reader::Location begin, Reader::Location end) {
return std::any_of(begin, end, [](char b) { return b == '\n' || b == '\r'; });
}
// Class Reader
// //////////////////////////////////////////////////////////////////
Reader::Reader() : features_(Features::all()) {}
Reader::Reader(const Features& features) : features_(features) {}
bool Reader::parse(const std::string& document, Value& root,
bool collectComments) {
document_.assign(document.begin(), document.end());
const char* begin = document_.c_str();
const char* end = begin + document_.length();
return parse(begin, end, root, collectComments);
}
bool Reader::parse(std::istream& is, Value& root, bool collectComments) {
// std::istream_iterator<char> begin(is);
// std::istream_iterator<char> end;
// Those would allow streamed input from a file, if parse() were a
// template function.
// Since String is reference-counted, this at least does not
// create an extra copy.
String doc(std::istreambuf_iterator<char>(is), {});
return parse(doc.data(), doc.data() + doc.size(), root, collectComments);
}
bool Reader::parse(const char* beginDoc, const char* endDoc, Value& root,
bool collectComments) {
if (!features_.allowComments_) {
collectComments = false;
}
begin_ = beginDoc;
end_ = endDoc;
collectComments_ = collectComments;
current_ = begin_;
lastValueEnd_ = nullptr;
lastValue_ = nullptr;
commentsBefore_.clear();
errors_.clear();
while (!nodes_.empty())
nodes_.pop();
nodes_.push(&root);
bool successful = readValue();
Token token;
skipCommentTokens(token);
if (collectComments_ && !commentsBefore_.empty())
root.setComment(commentsBefore_, commentAfter);
if (features_.strictRoot_) {
if (!root.isArray() && !root.isObject()) {
// Set error location to start of doc, ideally should be first token found
// in doc
token.type_ = tokenError;
token.start_ = beginDoc;
token.end_ = endDoc;
addError(
"A valid JSON document must be either an array or an object value.",
token);
return false;
}
}
return successful;
}
bool Reader::readValue() {
// readValue() may call itself only if it calls readObject() or ReadArray().
// These methods execute nodes_.push() just before and nodes_.pop)() just
// after calling readValue(). parse() executes one nodes_.push(), so > instead
// of >=.
if (nodes_.size() > stackLimit_g)
throwRuntimeError("Exceeded stackLimit in readValue().");
Token token;
skipCommentTokens(token);
bool successful = true;
if (collectComments_ && !commentsBefore_.empty()) {
currentValue().setComment(commentsBefore_, commentBefore);
commentsBefore_.clear();
}
switch (token.type_) {
case tokenObjectBegin:
successful = readObject(token);
currentValue().setOffsetLimit(current_ - begin_);
break;
case tokenArrayBegin:
successful = readArray(token);
currentValue().setOffsetLimit(current_ - begin_);
break;
case tokenNumber:
successful = decodeNumber(token);
break;
case tokenString:
successful = decodeString(token);
break;
case tokenTrue: {
Value v(true);
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenFalse: {
Value v(false);
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenNull: {
Value v;
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenArraySeparator:
case tokenObjectEnd:
case tokenArrayEnd:
if (features_.allowDroppedNullPlaceholders_) {
// "Un-read" the current token and mark the current value as a null
// token.
current_--;
Value v;
currentValue().swapPayload(v);
currentValue().setOffsetStart(current_ - begin_ - 1);
currentValue().setOffsetLimit(current_ - begin_);
break;
} // Else, fall through...
default:
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return addError("Syntax error: value, object or array expected.", token);
}
if (collectComments_) {
lastValueEnd_ = current_;
lastValue_ = &currentValue();
}
return successful;
}
void Reader::skipCommentTokens(Token& token) {
if (features_.allowComments_) {
do {
readToken(token);
} while (token.type_ == tokenComment);
} else {
readToken(token);
}
}
bool Reader::readToken(Token& token) {
skipSpaces();
token.start_ = current_;
Char c = getNextChar();
bool ok = true;
switch (c) {
case '{':
token.type_ = tokenObjectBegin;
break;
case '}':
token.type_ = tokenObjectEnd;
break;
case '[':
token.type_ = tokenArrayBegin;
break;
case ']':
token.type_ = tokenArrayEnd;
break;
case '"':
token.type_ = tokenString;
ok = readString();
break;
case '/':
token.type_ = tokenComment;
ok = readComment();
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
case '-':
token.type_ = tokenNumber;
readNumber();
break;
case 't':
token.type_ = tokenTrue;
ok = match("rue", 3);
break;
case 'f':
token.type_ = tokenFalse;
ok = match("alse", 4);
break;
case 'n':
token.type_ = tokenNull;
ok = match("ull", 3);
break;
case ',':
token.type_ = tokenArraySeparator;
break;
case ':':
token.type_ = tokenMemberSeparator;
break;
case 0:
token.type_ = tokenEndOfStream;
break;
default:
ok = false;
break;
}
if (!ok)
token.type_ = tokenError;
token.end_ = current_;
return ok;
}
void Reader::skipSpaces() {
while (current_ != end_) {
Char c = *current_;
if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
++current_;
else
break;
}
}
bool Reader::match(const Char* pattern, int patternLength) {
if (end_ - current_ < patternLength)
return false;
int index = patternLength;
while (index--)
if (current_[index] != pattern[index])
return false;
current_ += patternLength;
return true;
}
bool Reader::readComment() {
Location commentBegin = current_ - 1;
Char c = getNextChar();
bool successful = false;
if (c == '*')
successful = readCStyleComment();
else if (c == '/')
successful = readCppStyleComment();
if (!successful)
return false;
if (collectComments_) {
CommentPlacement placement = commentBefore;
if (lastValueEnd_ && !containsNewLine(lastValueEnd_, commentBegin)) {
if (c != '*' || !containsNewLine(commentBegin, current_))
placement = commentAfterOnSameLine;
}
addComment(commentBegin, current_, placement);
}
return true;
}
String Reader::normalizeEOL(Reader::Location begin, Reader::Location end) {
String normalized;
normalized.reserve(static_cast<size_t>(end - begin));
Reader::Location current = begin;
while (current != end) {
char c = *current++;
if (c == '\r') {
if (current != end && *current == '\n')
// convert dos EOL
++current;
// convert Mac EOL
normalized += '\n';
} else {
normalized += c;
}
}
return normalized;
}
void Reader::addComment(Location begin, Location end,
CommentPlacement placement) {
assert(collectComments_);
const String& normalized = normalizeEOL(begin, end);
if (placement == commentAfterOnSameLine) {
assert(lastValue_ != nullptr);
lastValue_->setComment(normalized, placement);
} else {
commentsBefore_ += normalized;
}
}
bool Reader::readCStyleComment() {
while ((current_ + 1) < end_) {
Char c = getNextChar();
if (c == '*' && *current_ == '/')
break;
}
return getNextChar() == '/';
}
bool Reader::readCppStyleComment() {
while (current_ != end_) {
Char c = getNextChar();
if (c == '\n')
break;
if (c == '\r') {
// Consume DOS EOL. It will be normalized in addComment.
if (current_ != end_ && *current_ == '\n')
getNextChar();
// Break on Moc OS 9 EOL.
break;
}
}
return true;
}
void Reader::readNumber() {
Location p = current_;
char c = '0'; // stopgap for already consumed character
// integral part
while (c >= '0' && c <= '9')
c = (current_ = p) < end_ ? *p++ : '\0';
// fractional part
if (c == '.') {
c = (current_ = p) < end_ ? *p++ : '\0';
while (c >= '0' && c <= '9')
c = (current_ = p) < end_ ? *p++ : '\0';
}
// exponential part
if (c == 'e' || c == 'E') {
c = (current_ = p) < end_ ? *p++ : '\0';
if (c == '+' || c == '-')
c = (current_ = p) < end_ ? *p++ : '\0';
while (c >= '0' && c <= '9')
c = (current_ = p) < end_ ? *p++ : '\0';
}
}
bool Reader::readString() {
Char c = '\0';
while (current_ != end_) {
c = getNextChar();
if (c == '\\')
getNextChar();
else if (c == '"')
break;
}
return c == '"';
}
bool Reader::readObject(Token& token) {
Token tokenName;
String name;
Value init(objectValue);
currentValue().swapPayload(init);
currentValue().setOffsetStart(token.start_ - begin_);
while (readToken(tokenName)) {
bool initialTokenOk = true;
while (tokenName.type_ == tokenComment && initialTokenOk)
initialTokenOk = readToken(tokenName);
if (!initialTokenOk)
break;
if (tokenName.type_ == tokenObjectEnd && name.empty()) // empty object
return true;
name.clear();
if (tokenName.type_ == tokenString) {
if (!decodeString(tokenName, name))
return recoverFromError(tokenObjectEnd);
} else if (tokenName.type_ == tokenNumber && features_.allowNumericKeys_) {
Value numberName;
if (!decodeNumber(tokenName, numberName))
return recoverFromError(tokenObjectEnd);
name = numberName.asString();
} else {
break;
}
Token colon;
if (!readToken(colon) || colon.type_ != tokenMemberSeparator) {
return addErrorAndRecover("Missing ':' after object member name", colon,
tokenObjectEnd);
}
Value& value = currentValue()[name];
nodes_.push(&value);
bool ok = readValue();
nodes_.pop();
if (!ok) // error already set
return recoverFromError(tokenObjectEnd);
Token comma;
if (!readToken(comma) ||
(comma.type_ != tokenObjectEnd && comma.type_ != tokenArraySeparator &&
comma.type_ != tokenComment)) {
return addErrorAndRecover("Missing ',' or '}' in object declaration",
comma, tokenObjectEnd);
}
bool finalizeTokenOk = true;
while (comma.type_ == tokenComment && finalizeTokenOk)
finalizeTokenOk = readToken(comma);
if (comma.type_ == tokenObjectEnd)
return true;
}
return addErrorAndRecover("Missing '}' or object member name", tokenName,
tokenObjectEnd);
}
bool Reader::readArray(Token& token) {
Value init(arrayValue);
currentValue().swapPayload(init);
currentValue().setOffsetStart(token.start_ - begin_);
skipSpaces();
if (current_ != end_ && *current_ == ']') // empty array
{
Token endArray;
readToken(endArray);
return true;
}
int index = 0;
for (;;) {
Value& value = currentValue()[index++];
nodes_.push(&value);
bool ok = readValue();
nodes_.pop();
if (!ok) // error already set
return recoverFromError(tokenArrayEnd);
Token currentToken;
// Accept Comment after last item in the array.
ok = readToken(currentToken);
while (currentToken.type_ == tokenComment && ok) {
ok = readToken(currentToken);
}
bool badTokenType = (currentToken.type_ != tokenArraySeparator &&
currentToken.type_ != tokenArrayEnd);
if (!ok || badTokenType) {
return addErrorAndRecover("Missing ',' or ']' in array declaration",
currentToken, tokenArrayEnd);
}
if (currentToken.type_ == tokenArrayEnd)
break;
}
return true;
}
bool Reader::decodeNumber(Token& token) {
Value decoded;
if (!decodeNumber(token, decoded))
return false;
currentValue().swapPayload(decoded);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return true;
}
bool Reader::decodeNumber(Token& token, Value& decoded) {
// Attempts to parse the number as an integer. If the number is
// larger than the maximum supported value of an integer then
// we decode the number as a double.
Location current = token.start_;
bool isNegative = *current == '-';
if (isNegative)
++current;
// TODO: Help the compiler do the div and mod at compile time or get rid of
// them.
Value::LargestUInt maxIntegerValue =
isNegative ? Value::LargestUInt(Value::maxLargestInt) + 1
: Value::maxLargestUInt;
Value::LargestUInt threshold = maxIntegerValue / 10;
Value::LargestUInt value = 0;
while (current < token.end_) {
Char c = *current++;
if (c < '0' || c > '9')
return decodeDouble(token, decoded);
auto digit(static_cast<Value::UInt>(c - '0'));
if (value >= threshold) {
// We've hit or exceeded the max value divided by 10 (rounded down). If
// a) we've only just touched the limit, b) this is the last digit, and
// c) it's small enough to fit in that rounding delta, we're okay.
// Otherwise treat this number as a double to avoid overflow.
if (value > threshold || current != token.end_ ||
digit > maxIntegerValue % 10) {
return decodeDouble(token, decoded);
}
}
value = value * 10 + digit;
}
if (isNegative && value == maxIntegerValue)
decoded = Value::minLargestInt;
else if (isNegative)
decoded = -Value::LargestInt(value);
else if (value <= Value::LargestUInt(Value::maxInt))
decoded = Value::LargestInt(value);
else
decoded = value;
return true;
}
bool Reader::decodeDouble(Token& token) {
Value decoded;
if (!decodeDouble(token, decoded))
return false;
currentValue().swapPayload(decoded);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return true;
}
bool Reader::decodeDouble(Token& token, Value& decoded) {
double value = 0;
String buffer(token.start_, token.end_);
IStringStream is(buffer);
if (!(is >> value)) {
if (value == std::numeric_limits<double>::max())
value = std::numeric_limits<double>::infinity();
else if (value == std::numeric_limits<double>::lowest())
value = -std::numeric_limits<double>::infinity();
else if (!std::isinf(value))
return addError(
"'" + String(token.start_, token.end_) + "' is not a number.", token);
}
decoded = value;
return true;
}
bool Reader::decodeString(Token& token) {
String decoded_string;
if (!decodeString(token, decoded_string))
return false;
Value decoded(decoded_string);
currentValue().swapPayload(decoded);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return true;
}
bool Reader::decodeString(Token& token, String& decoded) {
decoded.reserve(static_cast<size_t>(token.end_ - token.start_ - 2));
Location current = token.start_ + 1; // skip '"'
Location end = token.end_ - 1; // do not include '"'
while (current != end) {
Char c = *current++;
if (c == '"')
break;
if (c == '\\') {
if (current == end)
return addError("Empty escape sequence in string", token, current);
Char escape = *current++;
switch (escape) {
case '"':
decoded += '"';
break;
case '/':
decoded += '/';
break;
case '\\':
decoded += '\\';
break;
case 'b':
decoded += '\b';
break;
case 'f':
decoded += '\f';
break;
case 'n':
decoded += '\n';
break;
case 'r':
decoded += '\r';
break;
case 't':
decoded += '\t';
break;
case 'u': {
unsigned int unicode;
if (!decodeUnicodeCodePoint(token, current, end, unicode))
return false;
decoded += codePointToUTF8(unicode);
} break;
default:
return addError("Bad escape sequence in string", token, current);
}
} else {
decoded += c;
}
}
return true;
}
bool Reader::decodeUnicodeCodePoint(Token& token, Location& current,
Location end, unsigned int& unicode) {
if (!decodeUnicodeEscapeSequence(token, current, end, unicode))
return false;
if (unicode >= 0xD800 && unicode <= 0xDBFF) {
// surrogate pairs
if (end - current < 6)
return addError(
"additional six characters expected to parse unicode surrogate pair.",
token, current);
if (*(current++) == '\\' && *(current++) == 'u') {
unsigned int surrogatePair;
if (decodeUnicodeEscapeSequence(token, current, end, surrogatePair)) {
unicode = 0x10000 + ((unicode & 0x3FF) << 10) + (surrogatePair & 0x3FF);
} else
return false;
} else
return addError("expecting another \\u token to begin the second half of "
"a unicode surrogate pair",
token, current);
}
return true;
}
bool Reader::decodeUnicodeEscapeSequence(Token& token, Location& current,
Location end,
unsigned int& ret_unicode) {
if (end - current < 4)
return addError(
"Bad unicode escape sequence in string: four digits expected.", token,
current);
int unicode = 0;
for (int index = 0; index < 4; ++index) {
Char c = *current++;
unicode *= 16;
if (c >= '0' && c <= '9')
unicode += c - '0';
else if (c >= 'a' && c <= 'f')
unicode += c - 'a' + 10;
else if (c >= 'A' && c <= 'F')
unicode += c - 'A' + 10;
else
return addError(
"Bad unicode escape sequence in string: hexadecimal digit expected.",
token, current);
}
ret_unicode = static_cast<unsigned int>(unicode);
return true;
}
bool Reader::addError(const String& message, Token& token, Location extra) {
ErrorInfo info;
info.token_ = token;
info.message_ = message;
info.extra_ = extra;
errors_.push_back(info);
return false;
}
bool Reader::recoverFromError(TokenType skipUntilToken) {
size_t const errorCount = errors_.size();
Token skip;
for (;;) {
if (!readToken(skip))
errors_.resize(errorCount); // discard errors caused by recovery
if (skip.type_ == skipUntilToken || skip.type_ == tokenEndOfStream)
break;
}
errors_.resize(errorCount);
return false;
}
bool Reader::addErrorAndRecover(const String& message, Token& token,
TokenType skipUntilToken) {
addError(message, token);
return recoverFromError(skipUntilToken);
}
Value& Reader::currentValue() { return *(nodes_.top()); }
Reader::Char Reader::getNextChar() {
if (current_ == end_)
return 0;
return *current_++;
}
void Reader::getLocationLineAndColumn(Location location, int& line,
int& column) const {
Location current = begin_;
Location lastLineStart = current;
line = 0;
while (current < location && current != end_) {
Char c = *current++;
if (c == '\r') {
if (*current == '\n')
++current;
lastLineStart = current;
++line;
} else if (c == '\n') {
lastLineStart = current;
++line;
}
}
// column & line start at 1
column = int(location - lastLineStart) + 1;
++line;
}
String Reader::getLocationLineAndColumn(Location location) const {
int line, column;
getLocationLineAndColumn(location, line, column);
char buffer[18 + 16 + 16 + 1];
jsoncpp_snprintf(buffer, sizeof(buffer), "Line %d, Column %d", line, column);
return buffer;
}
// Deprecated. Preserved for backward compatibility
String Reader::getFormatedErrorMessages() const {
return getFormattedErrorMessages();
}
String Reader::getFormattedErrorMessages() const {
String formattedMessage;
for (const auto& error : errors_) {
formattedMessage +=
"* " + getLocationLineAndColumn(error.token_.start_) + "\n";
formattedMessage += " " + error.message_ + "\n";
if (error.extra_)
formattedMessage +=
"See " + getLocationLineAndColumn(error.extra_) + " for detail.\n";
}
return formattedMessage;
}
std::vector<Reader::StructuredError> Reader::getStructuredErrors() const {
std::vector<Reader::StructuredError> allErrors;
for (const auto& error : errors_) {
Reader::StructuredError structured;
structured.offset_start = error.token_.start_ - begin_;
structured.offset_limit = error.token_.end_ - begin_;
structured.message = error.message_;
allErrors.push_back(structured);
}
return allErrors;
}
bool Reader::pushError(const Value& value, const String& message) {
ptrdiff_t const length = end_ - begin_;
if (value.getOffsetStart() > length || value.getOffsetLimit() > length)
return false;
Token token;
token.type_ = tokenError;
token.start_ = begin_ + value.getOffsetStart();
token.end_ = begin_ + value.getOffsetLimit();
ErrorInfo info;
info.token_ = token;
info.message_ = message;
info.extra_ = nullptr;
errors_.push_back(info);
return true;
}
bool Reader::pushError(const Value& value, const String& message,
const Value& extra) {
ptrdiff_t const length = end_ - begin_;
if (value.getOffsetStart() > length || value.getOffsetLimit() > length ||
extra.getOffsetLimit() > length)
return false;
Token token;
token.type_ = tokenError;
token.start_ = begin_ + value.getOffsetStart();
token.end_ = begin_ + value.getOffsetLimit();
ErrorInfo info;
info.token_ = token;
info.message_ = message;
info.extra_ = begin_ + extra.getOffsetStart();
errors_.push_back(info);
return true;
}
bool Reader::good() const { return errors_.empty(); }
// Originally copied from the Features class (now deprecated), used internally
// for features implementation.
class OurFeatures {
public:
static OurFeatures all();
bool allowComments_;
bool allowTrailingCommas_;
bool strictRoot_;
bool allowDroppedNullPlaceholders_;
bool allowNumericKeys_;
bool allowSingleQuotes_;
bool failIfExtra_;
bool rejectDupKeys_;
bool allowSpecialFloats_;
bool skipBom_;
size_t stackLimit_;
}; // OurFeatures
OurFeatures OurFeatures::all() { return {}; }
// Implementation of class Reader
// ////////////////////////////////
// Originally copied from the Reader class (now deprecated), used internally
// for implementing JSON reading.
class OurReader {
public:
using Char = char;
using Location = const Char*;
struct StructuredError {
ptrdiff_t offset_start;
ptrdiff_t offset_limit;
String message;
};
explicit OurReader(OurFeatures const& features);
bool parse(const char* beginDoc, const char* endDoc, Value& root,
bool collectComments = true);
String getFormattedErrorMessages() const;
std::vector<StructuredError> getStructuredErrors() const;
private:
OurReader(OurReader const&); // no impl
void operator=(OurReader const&); // no impl
enum TokenType {
tokenEndOfStream = 0,
tokenObjectBegin,
tokenObjectEnd,
tokenArrayBegin,
tokenArrayEnd,
tokenString,
tokenNumber,
tokenTrue,
tokenFalse,
tokenNull,
tokenNaN,
tokenPosInf,
tokenNegInf,
tokenArraySeparator,
tokenMemberSeparator,
tokenComment,
tokenError
};
class Token {
public:
TokenType type_;
Location start_;
Location end_;
};
class ErrorInfo {
public:
Token token_;
String message_;
Location extra_;
};
using Errors = std::deque<ErrorInfo>;
bool readToken(Token& token);
void skipSpaces();
void skipBom(bool skipBom);
bool match(const Char* pattern, int patternLength);
bool readComment();
bool readCStyleComment(bool* containsNewLineResult);
bool readCppStyleComment();
bool readString();
bool readStringSingleQuote();
bool readNumber(bool checkInf);
bool readValue();
bool readObject(Token& token);
bool readArray(Token& token);
bool decodeNumber(Token& token);
bool decodeNumber(Token& token, Value& decoded);
bool decodeString(Token& token);
bool decodeString(Token& token, String& decoded);
bool decodeDouble(Token& token);
bool decodeDouble(Token& token, Value& decoded);
bool decodeUnicodeCodePoint(Token& token, Location& current, Location end,
unsigned int& unicode);
bool decodeUnicodeEscapeSequence(Token& token, Location& current,
Location end, unsigned int& unicode);
bool addError(const String& message, Token& token, Location extra = nullptr);
bool recoverFromError(TokenType skipUntilToken);
bool addErrorAndRecover(const String& message, Token& token,
TokenType skipUntilToken);
void skipUntilSpace();
Value& currentValue();
Char getNextChar();
void getLocationLineAndColumn(Location location, int& line,
int& column) const;
String getLocationLineAndColumn(Location location) const;
void addComment(Location begin, Location end, CommentPlacement placement);
void skipCommentTokens(Token& token);
static String normalizeEOL(Location begin, Location end);
static bool containsNewLine(Location begin, Location end);
using Nodes = std::stack<Value*>;
Nodes nodes_{};
Errors errors_{};
String document_{};
Location begin_ = nullptr;
Location end_ = nullptr;
Location current_ = nullptr;
Location lastValueEnd_ = nullptr;
Value* lastValue_ = nullptr;
bool lastValueHasAComment_ = false;
String commentsBefore_{};
OurFeatures const features_;
bool collectComments_ = false;
}; // OurReader
// complete copy of Read impl, for OurReader
bool OurReader::containsNewLine(OurReader::Location begin,
OurReader::Location end) {
return std::any_of(begin, end, [](char b) { return b == '\n' || b == '\r'; });
}
OurReader::OurReader(OurFeatures const& features) : features_(features) {}
bool OurReader::parse(const char* beginDoc, const char* endDoc, Value& root,
bool collectComments) {
if (!features_.allowComments_) {
collectComments = false;
}
begin_ = beginDoc;
end_ = endDoc;
collectComments_ = collectComments;
current_ = begin_;
lastValueEnd_ = nullptr;
lastValue_ = nullptr;
commentsBefore_.clear();
errors_.clear();
while (!nodes_.empty())
nodes_.pop();
nodes_.push(&root);
// skip byte order mark if it exists at the beginning of the UTF-8 text.
skipBom(features_.skipBom_);
bool successful = readValue();
nodes_.pop();
Token token;
skipCommentTokens(token);
if (features_.failIfExtra_ && (token.type_ != tokenEndOfStream)) {
addError("Extra non-whitespace after JSON value.", token);
return false;
}
if (collectComments_ && !commentsBefore_.empty())
root.setComment(commentsBefore_, commentAfter);
if (features_.strictRoot_) {
if (!root.isArray() && !root.isObject()) {
// Set error location to start of doc, ideally should be first token found
// in doc
token.type_ = tokenError;
token.start_ = beginDoc;
token.end_ = endDoc;
addError(
"A valid JSON document must be either an array or an object value.",
token);
return false;
}
}
return successful;
}
bool OurReader::readValue() {
// To preserve the old behaviour we cast size_t to int.
if (nodes_.size() > features_.stackLimit_)
throwRuntimeError("Exceeded stackLimit in readValue().");
Token token;
skipCommentTokens(token);
bool successful = true;
if (collectComments_ && !commentsBefore_.empty()) {
currentValue().setComment(commentsBefore_, commentBefore);
commentsBefore_.clear();
}
switch (token.type_) {
case tokenObjectBegin:
successful = readObject(token);
currentValue().setOffsetLimit(current_ - begin_);
break;
case tokenArrayBegin:
successful = readArray(token);
currentValue().setOffsetLimit(current_ - begin_);
break;
case tokenNumber:
successful = decodeNumber(token);
break;
case tokenString:
successful = decodeString(token);
break;
case tokenTrue: {
Value v(true);
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenFalse: {
Value v(false);
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenNull: {
Value v;
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenNaN: {
Value v(std::numeric_limits<double>::quiet_NaN());
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenPosInf: {
Value v(std::numeric_limits<double>::infinity());
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenNegInf: {
Value v(-std::numeric_limits<double>::infinity());
currentValue().swapPayload(v);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
} break;
case tokenArraySeparator:
case tokenObjectEnd:
case tokenArrayEnd:
if (features_.allowDroppedNullPlaceholders_) {
// "Un-read" the current token and mark the current value as a null
// token.
current_--;
Value v;
currentValue().swapPayload(v);
currentValue().setOffsetStart(current_ - begin_ - 1);
currentValue().setOffsetLimit(current_ - begin_);
break;
} // else, fall through ...
default:
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return addError("Syntax error: value, object or array expected.", token);
}
if (collectComments_) {
lastValueEnd_ = current_;
lastValueHasAComment_ = false;
lastValue_ = &currentValue();
}
return successful;
}
void OurReader::skipCommentTokens(Token& token) {
if (features_.allowComments_) {
do {
readToken(token);
} while (token.type_ == tokenComment);
} else {
readToken(token);
}
}
bool OurReader::readToken(Token& token) {
skipSpaces();
token.start_ = current_;
Char c = getNextChar();
bool ok = true;
switch (c) {
case '{':
token.type_ = tokenObjectBegin;
break;
case '}':
token.type_ = tokenObjectEnd;
break;
case '[':
token.type_ = tokenArrayBegin;
break;
case ']':
token.type_ = tokenArrayEnd;
break;
case '"':
token.type_ = tokenString;
ok = readString();
break;
case '\'':
if (features_.allowSingleQuotes_) {
token.type_ = tokenString;
ok = readStringSingleQuote();
} else {
// If we don't allow single quotes, this is a failure case.
ok = false;
}
break;
case '/':
token.type_ = tokenComment;
ok = readComment();
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
token.type_ = tokenNumber;
readNumber(false);
break;
case '-':
if (readNumber(true)) {
token.type_ = tokenNumber;
} else {
token.type_ = tokenNegInf;
ok = features_.allowSpecialFloats_ && match("nfinity", 7);
}
break;
case '+':
if (readNumber(true)) {
token.type_ = tokenNumber;
} else {
token.type_ = tokenPosInf;
ok = features_.allowSpecialFloats_ && match("nfinity", 7);
}
break;
case 't':
token.type_ = tokenTrue;
ok = match("rue", 3);
break;
case 'f':
token.type_ = tokenFalse;
ok = match("alse", 4);
break;
case 'n':
token.type_ = tokenNull;
ok = match("ull", 3);
break;
case 'N':
if (features_.allowSpecialFloats_) {
token.type_ = tokenNaN;
ok = match("aN", 2);
} else {
ok = false;
}
break;
case 'I':
if (features_.allowSpecialFloats_) {
token.type_ = tokenPosInf;
ok = match("nfinity", 7);
} else {
ok = false;
}
break;
case ',':
token.type_ = tokenArraySeparator;
break;
case ':':
token.type_ = tokenMemberSeparator;
break;
case 0:
token.type_ = tokenEndOfStream;
break;
default:
ok = false;
break;
}
if (!ok)
token.type_ = tokenError;
token.end_ = current_;
return ok;
}
void OurReader::skipSpaces() {
while (current_ != end_) {
Char c = *current_;
if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
++current_;
else
break;
}
}
void OurReader::skipBom(bool skipBom) {
// The default behavior is to skip BOM.
if (skipBom) {
if ((end_ - begin_) >= 3 && strncmp(begin_, "\xEF\xBB\xBF", 3) == 0) {
begin_ += 3;
current_ = begin_;
}
}
}
bool OurReader::match(const Char* pattern, int patternLength) {
if (end_ - current_ < patternLength)
return false;
int index = patternLength;
while (index--)
if (current_[index] != pattern[index])
return false;
current_ += patternLength;
return true;
}
bool OurReader::readComment() {
const Location commentBegin = current_ - 1;
const Char c = getNextChar();
bool successful = false;
bool cStyleWithEmbeddedNewline = false;
const bool isCStyleComment = (c == '*');
const bool isCppStyleComment = (c == '/');
if (isCStyleComment) {
successful = readCStyleComment(&cStyleWithEmbeddedNewline);
} else if (isCppStyleComment) {
successful = readCppStyleComment();
}
if (!successful)
return false;
if (collectComments_) {
CommentPlacement placement = commentBefore;
if (!lastValueHasAComment_) {
if (lastValueEnd_ && !containsNewLine(lastValueEnd_, commentBegin)) {
if (isCppStyleComment || !cStyleWithEmbeddedNewline) {
placement = commentAfterOnSameLine;
lastValueHasAComment_ = true;
}
}
}
addComment(commentBegin, current_, placement);
}
return true;
}
String OurReader::normalizeEOL(OurReader::Location begin,
OurReader::Location end) {
String normalized;
normalized.reserve(static_cast<size_t>(end - begin));
OurReader::Location current = begin;
while (current != end) {
char c = *current++;
if (c == '\r') {
if (current != end && *current == '\n')
// convert dos EOL
++current;
// convert Mac EOL
normalized += '\n';
} else {
normalized += c;
}
}
return normalized;
}
void OurReader::addComment(Location begin, Location end,
CommentPlacement placement) {
assert(collectComments_);
const String& normalized = normalizeEOL(begin, end);
if (placement == commentAfterOnSameLine) {
assert(lastValue_ != nullptr);
lastValue_->setComment(normalized, placement);
} else {
commentsBefore_ += normalized;
}
}
bool OurReader::readCStyleComment(bool* containsNewLineResult) {
*containsNewLineResult = false;
while ((current_ + 1) < end_) {
Char c = getNextChar();
if (c == '*' && *current_ == '/')
break;
if (c == '\n')
*containsNewLineResult = true;
}
return getNextChar() == '/';
}
bool OurReader::readCppStyleComment() {
while (current_ != end_) {
Char c = getNextChar();
if (c == '\n')
break;
if (c == '\r') {
// Consume DOS EOL. It will be normalized in addComment.
if (current_ != end_ && *current_ == '\n')
getNextChar();
// Break on Moc OS 9 EOL.
break;
}
}
return true;
}
bool OurReader::readNumber(bool checkInf) {
Location p = current_;
if (checkInf && p != end_ && *p == 'I') {
current_ = ++p;
return false;
}
char c = '0'; // stopgap for already consumed character
// integral part
while (c >= '0' && c <= '9')
c = (current_ = p) < end_ ? *p++ : '\0';
// fractional part
if (c == '.') {
c = (current_ = p) < end_ ? *p++ : '\0';
while (c >= '0' && c <= '9')
c = (current_ = p) < end_ ? *p++ : '\0';
}
// exponential part
if (c == 'e' || c == 'E') {
c = (current_ = p) < end_ ? *p++ : '\0';
if (c == '+' || c == '-')
c = (current_ = p) < end_ ? *p++ : '\0';
while (c >= '0' && c <= '9')
c = (current_ = p) < end_ ? *p++ : '\0';
}
return true;
}
bool OurReader::readString() {
Char c = 0;
while (current_ != end_) {
c = getNextChar();
if (c == '\\')
getNextChar();
else if (c == '"')
break;
}
return c == '"';
}
bool OurReader::readStringSingleQuote() {
Char c = 0;
while (current_ != end_) {
c = getNextChar();
if (c == '\\')
getNextChar();
else if (c == '\'')
break;
}
return c == '\'';
}
bool OurReader::readObject(Token& token) {
Token tokenName;
String name;
Value init(objectValue);
currentValue().swapPayload(init);
currentValue().setOffsetStart(token.start_ - begin_);
while (readToken(tokenName)) {
bool initialTokenOk = true;
while (tokenName.type_ == tokenComment && initialTokenOk)
initialTokenOk = readToken(tokenName);
if (!initialTokenOk)
break;
if (tokenName.type_ == tokenObjectEnd &&
(name.empty() ||
features_.allowTrailingCommas_)) // empty object or trailing comma
return true;
name.clear();
if (tokenName.type_ == tokenString) {
if (!decodeString(tokenName, name))
return recoverFromError(tokenObjectEnd);
} else if (tokenName.type_ == tokenNumber && features_.allowNumericKeys_) {
Value numberName;
if (!decodeNumber(tokenName, numberName))
return recoverFromError(tokenObjectEnd);
name = numberName.asString();
} else {
break;
}
if (name.length() >= (1U << 30))
throwRuntimeError("keylength >= 2^30");
if (features_.rejectDupKeys_ && currentValue().isMember(name)) {
String msg = "Duplicate key: '" + name + "'";
return addErrorAndRecover(msg, tokenName, tokenObjectEnd);
}
Token colon;
if (!readToken(colon) || colon.type_ != tokenMemberSeparator) {
return addErrorAndRecover("Missing ':' after object member name", colon,
tokenObjectEnd);
}
Value& value = currentValue()[name];
nodes_.push(&value);
bool ok = readValue();
nodes_.pop();
if (!ok) // error already set
return recoverFromError(tokenObjectEnd);
Token comma;
if (!readToken(comma) ||
(comma.type_ != tokenObjectEnd && comma.type_ != tokenArraySeparator &&
comma.type_ != tokenComment)) {
return addErrorAndRecover("Missing ',' or '}' in object declaration",
comma, tokenObjectEnd);
}
bool finalizeTokenOk = true;
while (comma.type_ == tokenComment && finalizeTokenOk)
finalizeTokenOk = readToken(comma);
if (comma.type_ == tokenObjectEnd)
return true;
}
return addErrorAndRecover("Missing '}' or object member name", tokenName,
tokenObjectEnd);
}
bool OurReader::readArray(Token& token) {
Value init(arrayValue);
currentValue().swapPayload(init);
currentValue().setOffsetStart(token.start_ - begin_);
int index = 0;
for (;;) {
skipSpaces();
if (current_ != end_ && *current_ == ']' &&
(index == 0 ||
(features_.allowTrailingCommas_ &&
!features_.allowDroppedNullPlaceholders_))) // empty array or trailing
// comma
{
Token endArray;
readToken(endArray);
return true;
}
Value& value = currentValue()[index++];
nodes_.push(&value);
bool ok = readValue();
nodes_.pop();
if (!ok) // error already set
return recoverFromError(tokenArrayEnd);
Token currentToken;
// Accept Comment after last item in the array.
ok = readToken(currentToken);
while (currentToken.type_ == tokenComment && ok) {
ok = readToken(currentToken);
}
bool badTokenType = (currentToken.type_ != tokenArraySeparator &&
currentToken.type_ != tokenArrayEnd);
if (!ok || badTokenType) {
return addErrorAndRecover("Missing ',' or ']' in array declaration",
currentToken, tokenArrayEnd);
}
if (currentToken.type_ == tokenArrayEnd)
break;
}
return true;
}
bool OurReader::decodeNumber(Token& token) {
Value decoded;
if (!decodeNumber(token, decoded))
return false;
currentValue().swapPayload(decoded);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return true;
}
bool OurReader::decodeNumber(Token& token, Value& decoded) {
// Attempts to parse the number as an integer. If the number is
// larger than the maximum supported value of an integer then
// we decode the number as a double.
Location current = token.start_;
const bool isNegative = *current == '-';
if (isNegative) {
++current;
}
// We assume we can represent the largest and smallest integer types as
// unsigned integers with separate sign. This is only true if they can fit
// into an unsigned integer.
static_assert(Value::maxLargestInt <= Value::maxLargestUInt,
"Int must be smaller than UInt");
// We need to convert minLargestInt into a positive number. The easiest way
// to do this conversion is to assume our "threshold" value of minLargestInt
// divided by 10 can fit in maxLargestInt when absolute valued. This should
// be a safe assumption.
static_assert(Value::minLargestInt <= -Value::maxLargestInt,
"The absolute value of minLargestInt must be greater than or "
"equal to maxLargestInt");
static_assert(Value::minLargestInt / 10 >= -Value::maxLargestInt,
"The absolute value of minLargestInt must be only 1 magnitude "
"larger than maxLargest Int");
static constexpr Value::LargestUInt positive_threshold =
Value::maxLargestUInt / 10;
static constexpr Value::UInt positive_last_digit = Value::maxLargestUInt % 10;
// For the negative values, we have to be more careful. Since typically
// -Value::minLargestInt will cause an overflow, we first divide by 10 and
// then take the inverse. This assumes that minLargestInt is only a single
// power of 10 different in magnitude, which we check above. For the last
// digit, we take the modulus before negating for the same reason.
static constexpr auto negative_threshold =
Value::LargestUInt(-(Value::minLargestInt / 10));
static constexpr auto negative_last_digit =
Value::UInt(-(Value::minLargestInt % 10));
const Value::LargestUInt threshold =
isNegative ? negative_threshold : positive_threshold;
const Value::UInt max_last_digit =
isNegative ? negative_last_digit : positive_last_digit;
Value::LargestUInt value = 0;
while (current < token.end_) {
Char c = *current++;
if (c < '0' || c > '9')
return decodeDouble(token, decoded);
const auto digit(static_cast<Value::UInt>(c - '0'));
if (value >= threshold) {
// We've hit or exceeded the max value divided by 10 (rounded down). If
// a) we've only just touched the limit, meaing value == threshold,
// b) this is the last digit, or
// c) it's small enough to fit in that rounding delta, we're okay.
// Otherwise treat this number as a double to avoid overflow.
if (value > threshold || current != token.end_ ||
digit > max_last_digit) {
return decodeDouble(token, decoded);
}
}
value = value * 10 + digit;
}
if (isNegative) {
// We use the same magnitude assumption here, just in case.
const auto last_digit = static_cast<Value::UInt>(value % 10);
decoded = -Value::LargestInt(value / 10) * 10 - last_digit;
} else if (value <= Value::LargestUInt(Value::maxLargestInt)) {
decoded = Value::LargestInt(value);
} else {
decoded = value;
}
return true;
}
bool OurReader::decodeDouble(Token& token) {
Value decoded;
if (!decodeDouble(token, decoded))
return false;
currentValue().swapPayload(decoded);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return true;
}
bool OurReader::decodeDouble(Token& token, Value& decoded) {
double value = 0;
const String buffer(token.start_, token.end_);
IStringStream is(buffer);
if (!(is >> value)) {
if (value == std::numeric_limits<double>::max())
value = std::numeric_limits<double>::infinity();
else if (value == std::numeric_limits<double>::lowest())
value = -std::numeric_limits<double>::infinity();
else if (!std::isinf(value))
return addError(
"'" + String(token.start_, token.end_) + "' is not a number.", token);
}
decoded = value;
return true;
}
bool OurReader::decodeString(Token& token) {
String decoded_string;
if (!decodeString(token, decoded_string))
return false;
Value decoded(decoded_string);
currentValue().swapPayload(decoded);
currentValue().setOffsetStart(token.start_ - begin_);
currentValue().setOffsetLimit(token.end_ - begin_);
return true;
}
bool OurReader::decodeString(Token& token, String& decoded) {
decoded.reserve(static_cast<size_t>(token.end_ - token.start_ - 2));
Location current = token.start_ + 1; // skip '"'
Location end = token.end_ - 1; // do not include '"'
while (current != end) {
Char c = *current++;
if (c == '"')
break;
if (c == '\\') {
if (current == end)
return addError("Empty escape sequence in string", token, current);
Char escape = *current++;
switch (escape) {
case '"':
decoded += '"';
break;
case '/':
decoded += '/';
break;
case '\\':
decoded += '\\';
break;
case 'b':
decoded += '\b';
break;
case 'f':
decoded += '\f';
break;
case 'n':
decoded += '\n';
break;
case 'r':
decoded += '\r';
break;
case 't':
decoded += '\t';
break;
case 'u': {
unsigned int unicode;
if (!decodeUnicodeCodePoint(token, current, end, unicode))
return false;
decoded += codePointToUTF8(unicode);
} break;
default:
return addError("Bad escape sequence in string", token, current);
}
} else {
decoded += c;
}
}
return true;
}
bool OurReader::decodeUnicodeCodePoint(Token& token, Location& current,
Location end, unsigned int& unicode) {
if (!decodeUnicodeEscapeSequence(token, current, end, unicode))
return false;
if (unicode >= 0xD800 && unicode <= 0xDBFF) {
// surrogate pairs
if (end - current < 6)
return addError(
"additional six characters expected to parse unicode surrogate pair.",
token, current);
if (*(current++) == '\\' && *(current++) == 'u') {
unsigned int surrogatePair;
if (decodeUnicodeEscapeSequence(token, current, end, surrogatePair)) {
unicode = 0x10000 + ((unicode & 0x3FF) << 10) + (surrogatePair & 0x3FF);
} else
return false;
} else
return addError("expecting another \\u token to begin the second half of "
"a unicode surrogate pair",
token, current);
}
return true;
}
bool OurReader::decodeUnicodeEscapeSequence(Token& token, Location& current,
Location end,
unsigned int& ret_unicode) {
if (end - current < 4)
return addError(
"Bad unicode escape sequence in string: four digits expected.", token,
current);
int unicode = 0;
for (int index = 0; index < 4; ++index) {
Char c = *current++;
unicode *= 16;
if (c >= '0' && c <= '9')
unicode += c - '0';
else if (c >= 'a' && c <= 'f')
unicode += c - 'a' + 10;
else if (c >= 'A' && c <= 'F')
unicode += c - 'A' + 10;
else
return addError(
"Bad unicode escape sequence in string: hexadecimal digit expected.",
token, current);
}
ret_unicode = static_cast<unsigned int>(unicode);
return true;
}
bool OurReader::addError(const String& message, Token& token, Location extra) {
ErrorInfo info;
info.token_ = token;
info.message_ = message;
info.extra_ = extra;
errors_.push_back(info);
return false;
}
bool OurReader::recoverFromError(TokenType skipUntilToken) {
size_t errorCount = errors_.size();
Token skip;
for (;;) {
if (!readToken(skip))
errors_.resize(errorCount); // discard errors caused by recovery
if (skip.type_ == skipUntilToken || skip.type_ == tokenEndOfStream)
break;
}
errors_.resize(errorCount);
return false;
}
bool OurReader::addErrorAndRecover(const String& message, Token& token,
TokenType skipUntilToken) {
addError(message, token);
return recoverFromError(skipUntilToken);
}
Value& OurReader::currentValue() { return *(nodes_.top()); }
OurReader::Char OurReader::getNextChar() {
if (current_ == end_)
return 0;
return *current_++;
}
void OurReader::getLocationLineAndColumn(Location location, int& line,
int& column) const {
Location current = begin_;
Location lastLineStart = current;
line = 0;
while (current < location && current != end_) {
Char c = *current++;
if (c == '\r') {
if (*current == '\n')
++current;
lastLineStart = current;
++line;
} else if (c == '\n') {
lastLineStart = current;
++line;
}
}
// column & line start at 1
column = int(location - lastLineStart) + 1;
++line;
}
String OurReader::getLocationLineAndColumn(Location location) const {
int line, column;
getLocationLineAndColumn(location, line, column);
char buffer[18 + 16 + 16 + 1];
jsoncpp_snprintf(buffer, sizeof(buffer), "Line %d, Column %d", line, column);
return buffer;
}
String OurReader::getFormattedErrorMessages() const {
String formattedMessage;
for (const auto& error : errors_) {
formattedMessage +=
"* " + getLocationLineAndColumn(error.token_.start_) + "\n";
formattedMessage += " " + error.message_ + "\n";
if (error.extra_)
formattedMessage +=
"See " + getLocationLineAndColumn(error.extra_) + " for detail.\n";
}
return formattedMessage;
}
std::vector<OurReader::StructuredError> OurReader::getStructuredErrors() const {
std::vector<OurReader::StructuredError> allErrors;
for (const auto& error : errors_) {
OurReader::StructuredError structured;
structured.offset_start = error.token_.start_ - begin_;
structured.offset_limit = error.token_.end_ - begin_;
structured.message = error.message_;
allErrors.push_back(structured);
}
return allErrors;
}
class OurCharReader : public CharReader {
bool const collectComments_;
OurReader reader_;
public:
OurCharReader(bool collectComments, OurFeatures const& features)
: collectComments_(collectComments), reader_(features) {}
bool parse(char const* beginDoc, char const* endDoc, Value* root,
String* errs) override {
bool ok = reader_.parse(beginDoc, endDoc, *root, collectComments_);
if (errs) {
*errs = reader_.getFormattedErrorMessages();
}
return ok;
}
};
CharReaderBuilder::CharReaderBuilder() { setDefaults(&settings_); }
CharReaderBuilder::~CharReaderBuilder() = default;
CharReader* CharReaderBuilder::newCharReader() const {
bool collectComments = settings_["collectComments"].asBool();
OurFeatures features = OurFeatures::all();
features.allowComments_ = settings_["allowComments"].asBool();
features.allowTrailingCommas_ = settings_["allowTrailingCommas"].asBool();
features.strictRoot_ = settings_["strictRoot"].asBool();
features.allowDroppedNullPlaceholders_ =
settings_["allowDroppedNullPlaceholders"].asBool();
features.allowNumericKeys_ = settings_["allowNumericKeys"].asBool();
features.allowSingleQuotes_ = settings_["allowSingleQuotes"].asBool();
// Stack limit is always a size_t, so we get this as an unsigned int
// regardless of it we have 64-bit integer support enabled.
features.stackLimit_ = static_cast<size_t>(settings_["stackLimit"].asUInt());
features.failIfExtra_ = settings_["failIfExtra"].asBool();
features.rejectDupKeys_ = settings_["rejectDupKeys"].asBool();
features.allowSpecialFloats_ = settings_["allowSpecialFloats"].asBool();
features.skipBom_ = settings_["skipBom"].asBool();
return new OurCharReader(collectComments, features);
}
bool CharReaderBuilder::validate(Json::Value* invalid) const {
static const auto& valid_keys = *new std::set<String>{
"collectComments",
"allowComments",
"allowTrailingCommas",
"strictRoot",
"allowDroppedNullPlaceholders",
"allowNumericKeys",
"allowSingleQuotes",
"stackLimit",
"failIfExtra",
"rejectDupKeys",
"allowSpecialFloats",
"skipBom",
};
for (auto si = settings_.begin(); si != settings_.end(); ++si) {
auto key = si.name();
if (valid_keys.count(key))
continue;
if (invalid)
(*invalid)[key] = *si;
else
return false;
}
return invalid ? invalid->empty() : true;
}
Value& CharReaderBuilder::operator[](const String& key) {
return settings_[key];
}
// static
void CharReaderBuilder::strictMode(Json::Value* settings) {
//! [CharReaderBuilderStrictMode]
(*settings)["allowComments"] = false;
(*settings)["allowTrailingCommas"] = false;
(*settings)["strictRoot"] = true;
(*settings)["allowDroppedNullPlaceholders"] = false;
(*settings)["allowNumericKeys"] = false;
(*settings)["allowSingleQuotes"] = false;
(*settings)["stackLimit"] = 1000;
(*settings)["failIfExtra"] = true;
(*settings)["rejectDupKeys"] = true;
(*settings)["allowSpecialFloats"] = false;
(*settings)["skipBom"] = true;
//! [CharReaderBuilderStrictMode]
}
// static
void CharReaderBuilder::setDefaults(Json::Value* settings) {
//! [CharReaderBuilderDefaults]
(*settings)["collectComments"] = true;
(*settings)["allowComments"] = true;
(*settings)["allowTrailingCommas"] = true;
(*settings)["strictRoot"] = false;
(*settings)["allowDroppedNullPlaceholders"] = false;
(*settings)["allowNumericKeys"] = false;
(*settings)["allowSingleQuotes"] = false;
(*settings)["stackLimit"] = 1000;
(*settings)["failIfExtra"] = false;
(*settings)["rejectDupKeys"] = false;
(*settings)["allowSpecialFloats"] = false;
(*settings)["skipBom"] = true;
//! [CharReaderBuilderDefaults]
}
//////////////////////////////////
// global functions
bool parseFromStream(CharReader::Factory const& fact, IStream& sin, Value* root,
String* errs) {
OStringStream ssin;
ssin << sin.rdbuf();
String doc = ssin.str();
char const* begin = doc.data();
char const* end = begin + doc.size();
// Note that we do not actually need a null-terminator.
CharReaderPtr const reader(fact.newCharReader());
return reader->parse(begin, end, root, errs);
}
IStream& operator>>(IStream& sin, Value& root) {
CharReaderBuilder b;
String errs;
bool ok = parseFromStream(b, sin, &root, &errs);
if (!ok) {
throwRuntimeError(errs);
}
return sin;
}
} // namespace Json
Reference in New Issue View Git Blame Copy Permalink