Files
rippled/src/ripple/json/impl/json_writer.cpp
2013-09-19 20:54:12 -07:00

932 lines
21 KiB
C++

//------------------------------------------------------------------------------
/*
Copyright (c) 2011-2013, OpenCoin, Inc.
*/
//==============================================================================
namespace Json
{
static bool isControlCharacter (char ch)
{
return ch > 0 && ch <= 0x1F;
}
static bool containsControlCharacter ( const char* str )
{
while ( *str )
{
if ( isControlCharacter ( * (str++) ) )
return true;
}
return false;
}
static void uintToString ( unsigned int value,
char*& current )
{
*--current = 0;
do
{
*--current = (value % 10) + '0';
value /= 10;
}
while ( value != 0 );
}
std::string valueToString ( Int value )
{
char buffer[32];
char* current = buffer + sizeof (buffer);
bool isNegative = value < 0;
if ( isNegative )
value = -value;
uintToString ( UInt (value), current );
if ( isNegative )
*--current = '-';
assert ( current >= buffer );
return current;
}
std::string valueToString ( UInt value )
{
char buffer[32];
char* current = buffer + sizeof (buffer);
uintToString ( value, current );
assert ( current >= buffer );
return current;
}
std::string valueToString ( double value )
{
char buffer[32];
#if defined(_MSC_VER) && defined(__STDC_SECURE_LIB__) // Use secure version with visual studio 2005 to avoid warning.
sprintf_s (buffer, sizeof (buffer), "%#f", value);
#else
sprintf (buffer, "%#f", value);
#endif
char* ch = buffer + strlen (buffer) - 1;
if (*ch != '0') return buffer; // nothing to truncate, so save time
while (ch > buffer && *ch == '0')
{
--ch;
}
char* last_nonzero = ch;
while (ch >= buffer)
{
switch (*ch)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
--ch;
continue;
case '.':
// Truncate zeroes to save bytes in output, but keep one.
* (last_nonzero + 2) = '\0';
return buffer;
default:
return buffer;
}
}
return buffer;
}
std::string valueToString ( bool value )
{
return value ? "true" : "false";
}
std::string valueToQuotedString ( const char* value )
{
// Not sure how to handle unicode...
if (strpbrk (value, "\"\\\b\f\n\r\t") == NULL && !containsControlCharacter ( value ))
return std::string ("\"") + value + "\"";
// We have to walk value and escape any special characters.
// Appending to std::string is not efficient, but this should be rare.
// (Note: forward slashes are *not* rare, but I am not escaping them.)
unsigned maxsize = strlen (value) * 2 + 3; // allescaped+quotes+NULL
std::string result;
result.reserve (maxsize); // to avoid lots of mallocs
result += "\"";
for (const char* c = value; *c != 0; ++c)
{
switch (*c)
{
case '\"':
result += "\\\"";
break;
case '\\':
result += "\\\\";
break;
case '\b':
result += "\\b";
break;
case '\f':
result += "\\f";
break;
case '\n':
result += "\\n";
break;
case '\r':
result += "\\r";
break;
case '\t':
result += "\\t";
break;
//case '/':
// Even though \/ is considered a legal escape in JSON, a bare
// slash is also legal, so I see no reason to escape it.
// (I hope I am not misunderstanding something.
// blep notes: actually escaping \/ may be useful in javascript to avoid </
// sequence.
// Should add a flag to allow this compatibility mode and prevent this
// sequence from occurring.
default:
if ( isControlCharacter ( *c ) )
{
std::ostringstream oss;
oss << "\\u" << std::hex << std::uppercase << std::setfill ('0') << std::setw (4) << static_cast<int> (*c);
result += oss.str ();
}
else
{
result += *c;
}
break;
}
}
result += "\"";
return result;
}
// Class Writer
// //////////////////////////////////////////////////////////////////
Writer::~Writer ()
{
}
// Class FastWriter
// //////////////////////////////////////////////////////////////////
FastWriter::FastWriter ()
: yamlCompatiblityEnabled_ ( false )
{
}
void
FastWriter::enableYAMLCompatibility ()
{
yamlCompatiblityEnabled_ = true;
}
std::string
FastWriter::write ( const Value& root )
{
document_ = "";
writeValue ( root );
document_ += "\n";
return document_;
}
void
FastWriter::writeValue ( const Value& value )
{
switch ( value.type () )
{
case nullValue:
document_ += "null";
break;
case intValue:
document_ += valueToString ( value.asInt () );
break;
case uintValue:
document_ += valueToString ( value.asUInt () );
break;
case realValue:
document_ += valueToString ( value.asDouble () );
break;
case stringValue:
document_ += valueToQuotedString ( value.asCString () );
break;
case booleanValue:
document_ += valueToString ( value.asBool () );
break;
case arrayValue:
{
document_ += "[";
int size = value.size ();
for ( int index = 0; index < size; ++index )
{
if ( index > 0 )
document_ += ",";
writeValue ( value[index] );
}
document_ += "]";
}
break;
case objectValue:
{
Value::Members members ( value.getMemberNames () );
document_ += "{";
for ( Value::Members::iterator it = members.begin ();
it != members.end ();
++it )
{
const std::string& name = *it;
if ( it != members.begin () )
document_ += ",";
document_ += valueToQuotedString ( name.c_str () );
document_ += yamlCompatiblityEnabled_ ? ": "
: ":";
writeValue ( value[name] );
}
document_ += "}";
}
break;
}
}
// Class StyledWriter
// //////////////////////////////////////////////////////////////////
StyledWriter::StyledWriter ()
: rightMargin_ ( 74 )
, indentSize_ ( 3 )
{
}
std::string
StyledWriter::write ( const Value& root )
{
document_ = "";
addChildValues_ = false;
indentString_ = "";
writeCommentBeforeValue ( root );
writeValue ( root );
writeCommentAfterValueOnSameLine ( root );
document_ += "\n";
return document_;
}
void
StyledWriter::writeValue ( const Value& value )
{
switch ( value.type () )
{
case nullValue:
pushValue ( "null" );
break;
case intValue:
pushValue ( valueToString ( value.asInt () ) );
break;
case uintValue:
pushValue ( valueToString ( value.asUInt () ) );
break;
case realValue:
pushValue ( valueToString ( value.asDouble () ) );
break;
case stringValue:
pushValue ( valueToQuotedString ( value.asCString () ) );
break;
case booleanValue:
pushValue ( valueToString ( value.asBool () ) );
break;
case arrayValue:
writeArrayValue ( value);
break;
case objectValue:
{
Value::Members members ( value.getMemberNames () );
if ( members.empty () )
pushValue ( "{}" );
else
{
writeWithIndent ( "{" );
indent ();
Value::Members::iterator it = members.begin ();
while ( true )
{
const std::string& name = *it;
const Value& childValue = value[name];
writeCommentBeforeValue ( childValue );
writeWithIndent ( valueToQuotedString ( name.c_str () ) );
document_ += " : ";
writeValue ( childValue );
if ( ++it == members.end () )
{
writeCommentAfterValueOnSameLine ( childValue );
break;
}
document_ += ",";
writeCommentAfterValueOnSameLine ( childValue );
}
unindent ();
writeWithIndent ( "}" );
}
}
break;
}
}
void
StyledWriter::writeArrayValue ( const Value& value )
{
unsigned size = value.size ();
if ( size == 0 )
pushValue ( "[]" );
else
{
bool isArrayMultiLine = isMultineArray ( value );
if ( isArrayMultiLine )
{
writeWithIndent ( "[" );
indent ();
bool hasChildValue = !childValues_.empty ();
unsigned index = 0;
while ( true )
{
const Value& childValue = value[index];
writeCommentBeforeValue ( childValue );
if ( hasChildValue )
writeWithIndent ( childValues_[index] );
else
{
writeIndent ();
writeValue ( childValue );
}
if ( ++index == size )
{
writeCommentAfterValueOnSameLine ( childValue );
break;
}
document_ += ",";
writeCommentAfterValueOnSameLine ( childValue );
}
unindent ();
writeWithIndent ( "]" );
}
else // output on a single line
{
assert ( childValues_.size () == size );
document_ += "[ ";
for ( unsigned index = 0; index < size; ++index )
{
if ( index > 0 )
document_ += ", ";
document_ += childValues_[index];
}
document_ += " ]";
}
}
}
bool
StyledWriter::isMultineArray ( const Value& value )
{
int size = value.size ();
bool isMultiLine = size * 3 >= rightMargin_ ;
childValues_.clear ();
for ( int index = 0; index < size && !isMultiLine; ++index )
{
const Value& childValue = value[index];
isMultiLine = isMultiLine ||
( (childValue.isArray () || childValue.isObject ()) &&
childValue.size () > 0 );
}
if ( !isMultiLine ) // check if line length > max line length
{
childValues_.reserve ( size );
addChildValues_ = true;
int lineLength = 4 + (size - 1) * 2; // '[ ' + ', '*n + ' ]'
for ( int index = 0; index < size && !isMultiLine; ++index )
{
writeValue ( value[index] );
lineLength += int ( childValues_[index].length () );
isMultiLine = isMultiLine && hasCommentForValue ( value[index] );
}
addChildValues_ = false;
isMultiLine = isMultiLine || lineLength >= rightMargin_;
}
return isMultiLine;
}
void
StyledWriter::pushValue ( const std::string& value )
{
if ( addChildValues_ )
childValues_.push_back ( value );
else
document_ += value;
}
void
StyledWriter::writeIndent ()
{
if ( !document_.empty () )
{
char last = document_[document_.length () - 1];
if ( last == ' ' ) // already indented
return;
if ( last != '\n' ) // Comments may add new-line
document_ += '\n';
}
document_ += indentString_;
}
void
StyledWriter::writeWithIndent ( const std::string& value )
{
writeIndent ();
document_ += value;
}
void
StyledWriter::indent ()
{
indentString_ += std::string ( indentSize_, ' ' );
}
void
StyledWriter::unindent ()
{
assert ( int (indentString_.size ()) >= indentSize_ );
indentString_.resize ( indentString_.size () - indentSize_ );
}
void
StyledWriter::writeCommentBeforeValue ( const Value& root )
{
if ( !root.hasComment ( commentBefore ) )
return;
document_ += normalizeEOL ( root.getComment ( commentBefore ) );
document_ += "\n";
}
void
StyledWriter::writeCommentAfterValueOnSameLine ( const Value& root )
{
if ( root.hasComment ( commentAfterOnSameLine ) )
document_ += " " + normalizeEOL ( root.getComment ( commentAfterOnSameLine ) );
if ( root.hasComment ( commentAfter ) )
{
document_ += "\n";
document_ += normalizeEOL ( root.getComment ( commentAfter ) );
document_ += "\n";
}
}
bool
StyledWriter::hasCommentForValue ( const Value& value )
{
return value.hasComment ( commentBefore )
|| value.hasComment ( commentAfterOnSameLine )
|| value.hasComment ( commentAfter );
}
std::string
StyledWriter::normalizeEOL ( const std::string& text )
{
std::string normalized;
normalized.reserve ( text.length () );
const char* begin = text.c_str ();
const char* end = begin + text.length ();
const char* current = begin;
while ( current != end )
{
char c = *current++;
if ( c == '\r' ) // mac or dos EOL
{
if ( *current == '\n' ) // convert dos EOL
++current;
normalized += '\n';
}
else // handle unix EOL & other char
normalized += c;
}
return normalized;
}
// Class StyledStreamWriter
// //////////////////////////////////////////////////////////////////
StyledStreamWriter::StyledStreamWriter ( std::string indentation )
: document_ (NULL)
, rightMargin_ ( 74 )
, indentation_ ( indentation )
{
}
void
StyledStreamWriter::write ( std::ostream& out, const Value& root )
{
document_ = &out;
addChildValues_ = false;
indentString_ = "";
writeCommentBeforeValue ( root );
writeValue ( root );
writeCommentAfterValueOnSameLine ( root );
*document_ << "\n";
document_ = NULL; // Forget the stream, for safety.
}
void
StyledStreamWriter::writeValue ( const Value& value )
{
switch ( value.type () )
{
case nullValue:
pushValue ( "null" );
break;
case intValue:
pushValue ( valueToString ( value.asInt () ) );
break;
case uintValue:
pushValue ( valueToString ( value.asUInt () ) );
break;
case realValue:
pushValue ( valueToString ( value.asDouble () ) );
break;
case stringValue:
pushValue ( valueToQuotedString ( value.asCString () ) );
break;
case booleanValue:
pushValue ( valueToString ( value.asBool () ) );
break;
case arrayValue:
writeArrayValue ( value);
break;
case objectValue:
{
Value::Members members ( value.getMemberNames () );
if ( members.empty () )
pushValue ( "{}" );
else
{
writeWithIndent ( "{" );
indent ();
Value::Members::iterator it = members.begin ();
while ( true )
{
const std::string& name = *it;
const Value& childValue = value[name];
writeCommentBeforeValue ( childValue );
writeWithIndent ( valueToQuotedString ( name.c_str () ) );
*document_ << " : ";
writeValue ( childValue );
if ( ++it == members.end () )
{
writeCommentAfterValueOnSameLine ( childValue );
break;
}
*document_ << ",";
writeCommentAfterValueOnSameLine ( childValue );
}
unindent ();
writeWithIndent ( "}" );
}
}
break;
}
}
void
StyledStreamWriter::writeArrayValue ( const Value& value )
{
unsigned size = value.size ();
if ( size == 0 )
pushValue ( "[]" );
else
{
bool isArrayMultiLine = isMultineArray ( value );
if ( isArrayMultiLine )
{
writeWithIndent ( "[" );
indent ();
bool hasChildValue = !childValues_.empty ();
unsigned index = 0;
while ( true )
{
const Value& childValue = value[index];
writeCommentBeforeValue ( childValue );
if ( hasChildValue )
writeWithIndent ( childValues_[index] );
else
{
writeIndent ();
writeValue ( childValue );
}
if ( ++index == size )
{
writeCommentAfterValueOnSameLine ( childValue );
break;
}
*document_ << ",";
writeCommentAfterValueOnSameLine ( childValue );
}
unindent ();
writeWithIndent ( "]" );
}
else // output on a single line
{
assert ( childValues_.size () == size );
*document_ << "[ ";
for ( unsigned index = 0; index < size; ++index )
{
if ( index > 0 )
*document_ << ", ";
*document_ << childValues_[index];
}
*document_ << " ]";
}
}
}
bool
StyledStreamWriter::isMultineArray ( const Value& value )
{
int size = value.size ();
bool isMultiLine = size * 3 >= rightMargin_ ;
childValues_.clear ();
for ( int index = 0; index < size && !isMultiLine; ++index )
{
const Value& childValue = value[index];
isMultiLine = isMultiLine ||
( (childValue.isArray () || childValue.isObject ()) &&
childValue.size () > 0 );
}
if ( !isMultiLine ) // check if line length > max line length
{
childValues_.reserve ( size );
addChildValues_ = true;
int lineLength = 4 + (size - 1) * 2; // '[ ' + ', '*n + ' ]'
for ( int index = 0; index < size && !isMultiLine; ++index )
{
writeValue ( value[index] );
lineLength += int ( childValues_[index].length () );
isMultiLine = isMultiLine && hasCommentForValue ( value[index] );
}
addChildValues_ = false;
isMultiLine = isMultiLine || lineLength >= rightMargin_;
}
return isMultiLine;
}
void
StyledStreamWriter::pushValue ( const std::string& value )
{
if ( addChildValues_ )
childValues_.push_back ( value );
else
*document_ << value;
}
void
StyledStreamWriter::writeIndent ()
{
/*
Some comments in this method would have been nice. ;-)
if ( !document_.empty() )
{
char last = document_[document_.length()-1];
if ( last == ' ' ) // already indented
return;
if ( last != '\n' ) // Comments may add new-line
*document_ << '\n';
}
*/
*document_ << '\n' << indentString_;
}
void
StyledStreamWriter::writeWithIndent ( const std::string& value )
{
writeIndent ();
*document_ << value;
}
void
StyledStreamWriter::indent ()
{
indentString_ += indentation_;
}
void
StyledStreamWriter::unindent ()
{
assert ( indentString_.size () >= indentation_.size () );
indentString_.resize ( indentString_.size () - indentation_.size () );
}
void
StyledStreamWriter::writeCommentBeforeValue ( const Value& root )
{
if ( !root.hasComment ( commentBefore ) )
return;
*document_ << normalizeEOL ( root.getComment ( commentBefore ) );
*document_ << "\n";
}
void
StyledStreamWriter::writeCommentAfterValueOnSameLine ( const Value& root )
{
if ( root.hasComment ( commentAfterOnSameLine ) )
*document_ << " " + normalizeEOL ( root.getComment ( commentAfterOnSameLine ) );
if ( root.hasComment ( commentAfter ) )
{
*document_ << "\n";
*document_ << normalizeEOL ( root.getComment ( commentAfter ) );
*document_ << "\n";
}
}
bool
StyledStreamWriter::hasCommentForValue ( const Value& value )
{
return value.hasComment ( commentBefore )
|| value.hasComment ( commentAfterOnSameLine )
|| value.hasComment ( commentAfter );
}
std::string
StyledStreamWriter::normalizeEOL ( const std::string& text )
{
std::string normalized;
normalized.reserve ( text.length () );
const char* begin = text.c_str ();
const char* end = begin + text.length ();
const char* current = begin;
while ( current != end )
{
char c = *current++;
if ( c == '\r' ) // mac or dos EOL
{
if ( *current == '\n' ) // convert dos EOL
++current;
normalized += '\n';
}
else // handle unix EOL & other char
normalized += c;
}
return normalized;
}
std::ostream& operator<< ( std::ostream& sout, const Value& root )
{
Json::StyledStreamWriter writer;
writer.write (sout, root);
return sout;
}
} // namespace Json