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/////////////////////////////////////////////////////////////////////////////
// Name: jsonwriter.cpp
// Purpose: the wxJSONWriter class: a JSON text generator
// Author: Luciano Cattani
// Created: 2007/10/12
// RCS-ID: $Id: jsonwriter.cpp,v 1.6 2008/03/03 19:05:47 luccat Exp $
// Copyright: (c) 2007 Luciano Cattani
// Licence: wxWidgets licence
/////////////////////////////////////////////////////////////////////////////
#ifdef __GNUG__
#pragma implementation "jsonwriter.cpp"
#endif
#include "jsonwriter.h"
#include <wx/sstream.h>
#include <wx/mstream.h>
#include <wx/debug.h>
#include <wx/log.h>
static const wxChar* writerTraceMask = _T("traceWriter");
/*! \class wxJSONWriter
\brief The JSON document writer
This class is a JSON document writer and it is used to write a
wxJSONValue object to an output stream or to a string object.
The ctor accepts some parameters which can be used to
change the style of the output.
The default output is in human-readable format that uses a three-space
indentation for object / array sub-items and separates every
value with a linefeed character.
\par Examples
Using the default writer constructor
\code
// construct the JSON value object and add values to it
wxJSONValue root;
root["key1"] = "some value";
...
// construct the string that will contain the JSON text
wxString str;
// construct a JSON writer: use the default writer's settings
wxJSONWriter writer;
// call the writer's Write() memberfunction
writer.Write( root, str );
\endcode
To write a JSON value object using a four-spaces indentation and forcing all
comment strings to apear before the value they refer to, use the following code:
\code
wxJSONWriter writer( wxJSONWRITER_STYLED | // want a styled output
wxJSONWRITER_WRITE_COMMENTS | // want comments in the document
wxJSONWRITER_COMMENTS_BEFORE, // force comments before value
0, // initial indentation
4); // indentation step
writer.Write( value, document );
\endcode
The following code construct a JSON writer that produces the most compact
text output but it is hard to read by humans:
\code
wxJSONWriter writer( wxJSONWRITER_NONE );
writer.Write( value, document );
\endcode
\par The two types of output objects
You can write JSON text to two different kind of objects:
\li a string object (\b wxString)
\li a stream object (\b wxOutputStream)
When writing to a string object, the output is platform- and mode-dependent.
In ANSI builds, the JSON text output in the string object will
contain one-byte characters: the actual characters represented is
locale dependent.
In Unicode builds, the JSON text output in the string contains
wide characters which encoding format is platform dependent: UCS-2 in
Windows, UCS-4 in GNU/Linux.
Starting from wxWidgets version 2.9 the internal encoding for Unicode
builds in linux/unix systems is UTF-8.
When writing to a stream object, the JSON text output is always
encoded in UTF-8 in both ANSI and Unicode builds.
In ANSI builds the user may want to suppress UTF-8 encoding so
that the JSON text can be stored in ANSI format.
Note that this is not valid JSON text unless all characters written
to the JSON text document are in the US-ASCII character ser (0x00..0x7F).
To know more read \ref wxjson_tutorial_unicode_ansi
\par Efficiency
In versions up to 1.0 the JSON writer wrote every character to the
output object (the string or the stream).
This is very inefficient becuase the writer converted each char to
UTF-8 when writing to streams but we have to note that only string values
have to be actually converted.
Special JSON characters, numbers and literals do not need the conversion
because they lay in the US-ASCII plane (0x00-0x7F)
and no conversion is needed as the UTF-8 encoding is the same as US-ASCII.
For more info about the unicode topic see \ref wxjson_tutorial_unicode.
\par The problem of writing doubles
You can customize the ouput of doubles by specifing the format string
that has to be used by the JSON writer class. To know more about this issue
read \ref wxjson_tutorial_write_doubles
*/
//! Ctor.
/*!
Construct the JSON writer object with the specified parameters.
Note that if \c styled is FALSE the indentation is totally suppressed
and the values of the other two parameters are simply ignored.
\param indent the initial indentation in number of spaces. Default is ZERO.
If you specify the wxJSONWRITER_TAB_INDENT flag for the \e style,
this value referes to the number of TABs in the initial indentation
\param step the indentation increment for new objects/arrays in number of spaces
(default is 3).
This value is ignored if you specify the wxJSONWRITER_TAB_INDENT flag for
the \e style: the indentation increment is only one TAB character.
\param style this is a combination of the following constants OR'ed togheter:
\li wxJSONWRITER_NONE: no indentation is performed and no LF character is
written between values.
This style produces strict JSON text but it is hard to read by humans
\li wxJSONWRITER_STYLED: output is human-readable: values are separated by
LF characters and sub-items are indented.
This style produces strict JSON text that is easy to read by humans.
\li wxJSONWRITER_WRITE_COMMENTS: this flag force the writer to write C/C++
comment strings, if any. The comments will be written in their original position.
C/C++ comments may not be recognized by other JSON implementations because
they are not strict JSON text.
\li wxJSONWRITER_COMMENTS_BEFORE: this flag force the writer to write C/C++ comments
always before the value they refer to.
In order for this style to take effect, you also have to specify the
wxJSONWRITER_WRITE_COMMENTS flag.
\li wxJSONWRITER_COMMENTS_AFTER: this flag force the writer to write C/C++ comments
always after the value they refer to.
In order for this style to take effect, you also have to specify the
wxJSONWRITER_WRITE_COMMENTS flag.
\li wxJSONWRITER_SPLIT_STRINGS: this flag cause the writer to split strings
in more than one line if they are too long.
\li wxJSONWRITER_NO_LINEFEEDS: this flag cause the JSON writer to not add
newlines between values. It is ignored if wxJSONWRITER_STYLED is not set.
This style produces strict JSON text.
\li wxJSONWRITER_ESCAPE_SOLIDUS: the solidus character (/) should only be
escaped if the JSON text is meant for embedding in HTML.
Unlike in older 0.x versions, it is disabled by default and this flag cause
the solidus char to be escaped.
This style produces strict JSON text.
\li wxJSONWRITER_MULTILINE_STRING:this is a multiline-string mode where newlines
and tabs are not escaped. This is not strict JSON, but it helps immensely when
manually editing json files with multiline strings
\li wxJSONWRITER_RECOGNIZE_UNSIGNED: this flag cause the JSON writer to prepend
a plus sign (+) to unsigned integer values. This is used by the wxJSON reader to
force the integer to be stored in an \b unsigned \b int. Note that this
feature may be incompatible with other JSON implementations.
\li wxJSONWRITER_TAB_INDENT: this flag cause the indentation of sub-objects / arrays
to be done using a TAB character instead of SPACES.
In order for this style to take effect, you also have to specify the
wxJSONWRITER_STYLED flag.
This style produces strict JSON text.
\li wxJSONWRITER_NO_INDENTATION: this flag cause the JSON writer to not add
indentation. It is ignored if wxJSONWRITER_STYLED is not set.
This style produces strict JSON text.
\li wxJSONWRITER_NOUTF8_STREAM: suppress UTF-8 conversion when writing string
values to the stream thus producing ANSI text output; only meaningfull in
ANSI builds, this flag is simply ignored in Unicode builds.
\li wxJSONWRITER_MEMORYBUFF:
Note that for the style wxJSONWRITER_NONE the JSON text output is a bit
different from that of old 0.x versions although it is syntactically equal.
If you rely on the old JSON output formatting read the following page
\ref wxjson_tutorial_style_none.
To know more about the writer's styles see \ref wxjson_tutorial_style
*/
wxJSONWriter::wxJSONWriter( int style, int indent, int step )
{
m_indent = indent;
m_step = step;
m_style = style;
m_noUtf8 = false;
if ( m_style == wxJSONWRITER_NONE ) {
m_indent = 0;
m_step = 0;
}
// set the default format string for doubles as
// 10 significant digits and suppress trailing ZEROes
SetDoubleFmtString( "%.10g") ;
#if !defined( wxJSON_USE_UNICODE )
// in ANSI builds we can suppress UTF-8 conversion for both the writer and the reader
if ( m_style == wxJSONWRITER_NOUTF8_STREAM ) {
m_noUtf8 = true;
}
#endif
}
//! Dtor - does nothing
wxJSONWriter::~wxJSONWriter()
{
}
//! Write the JSONvalue object to a JSON text.
/*!
The two overloaded versions of this function let the user choose
the output object which can be:
\li a string object (\b wxString)
\li a stream object ( \b wxOutputStream)
The two types of output object are very different because the
text outputted is encoded in different formats depending on the
build mode.
When writing to a string object, the JSON text output is encoded
differently depending on the build mode and the platform.
Writing to a stream always produce UTF-8 encoded text.
To know more about this topic read \ref wxjson_tutorial_unicode.
Also note that the Write() function does not return a status code.
If you are writing to a string, you do not have to warry about this
issue: no errors can occur when writing to strings.
On the other hand, wehn writing to a stream there could be errors
in the write operation.
If an error occurs, the \c Write(9 function immediatly returns
without trying further output operations.
You have to check the status of the stream by calling the stream's
memberfunctions. Example:
\code
// construct the JSON value object and add values to it
wxJSONValue root;
root["key1"] = "some value";
// write to a stream
wxMemoryOutputStream mem;
wxJSONWriter writer;
writer.Write( root, mem );
wxStreamError err = mem.GetLastError();
if ( err != wxSTREAM_NO_ERROR ) {
MessageBox( _T("ERROR: cannot write the JSON text output"));
}
\endcode
*/
void
wxJSONWriter::Write( const wxJSONValue& value, wxString& str )
{
#if !defined( wxJSON_USE_UNICODE )
// in ANSI builds output to a string never use UTF-8 conversion
bool noUtf8_bak = m_noUtf8; // save the current setting
m_noUtf8 = true;
#endif
wxMemoryOutputStream os;
Write( value, os );
// get the address of the buffer
wxFileOffset len = os.GetLength();
wxStreamBuffer* osBuff = os.GetOutputStreamBuffer();
void* buffStart = osBuff->GetBufferStart();
if ( m_noUtf8 ) {
str = wxString::From8BitData( (const char*) buffStart, len );
}
else {
str = wxString::FromUTF8( (const char*) buffStart, len );
}
#if !defined( wxJSON_USE_UNICODE )
m_noUtf8 = noUtf8_bak; // restore the old setting
#endif
}
//! \overload Write( const wxJSONValue&, wxString& )
void
wxJSONWriter::Write( const wxJSONValue& value, wxOutputStream& os )
{
m_level = 0;
DoWrite( os, value, 0, false );
}
//! Set the format string for double values.
/*!
This function sets the format string used for printing double values.
Double values are outputted to JSON text using the \b snprintf function
with a default format string of:
\code
%.10g
\endcode
which prints doubles with a precision of 10 decimal digits and suppressing
trailing ZEROes.
Note that the parameter is a pointer to \b char and not to \b wxChar. This
is because the JSON writer always procudes UTF-8 encoded text and decimal
digits in UTF-8 are made of only one UTF-8 code-unit (1 byte).
*/
void
wxJSONWriter::SetDoubleFmtString( const char* fmt )
{
m_fmt = (char*) fmt;
}
//! Perform the real write operation.
/*!
This is a recursive function that gets the type of the \c value object and
calls several protected functions depending on the type:
\li \c WriteNullvalue for type NULL
\li \c WriteStringValue() for STRING and CSTRING types
\li \c WriteIntValue for INT types
\li \c WriteUIntValue for UINT types
\li \c WriteBoolValue for BOOL types
\li \c WriteDoubleValue for DOUBLE types
\li \c WriteMemoryBuff for MEMORYBUFF types
If the value is an array or key/value map (types ARRAY and OBJECT), the function
iterates through all JSON value object in the array/map and calls itself for every
item in the container.
*/
int
wxJSONWriter::DoWrite( wxOutputStream& os, const wxJSONValue& value, const wxString* key, bool comma )
{
// note that this function is recursive
// some variables that cannot be allocated in the switch statement
const wxJSONInternalMap* map = 0;
int size;
m_colNo = 1; m_lineNo = 1;
// determine the comment position; it is one of:
//
// wxJSONVALUE_COMMENT_BEFORE
// wxJSONVALUE_COMMENT_AFTER
// wxJSONVALUE_COMMENT_INLINE
//
// or -1 if comments have not to be written
int commentPos = -1;
if ( value.GetCommentCount() > 0 && (m_style & wxJSONWRITER_WRITE_COMMENTS)) {
commentPos = value.GetCommentPos();
if ( ( m_style & wxJSONWRITER_COMMENTS_BEFORE) != 0 ) {
commentPos = wxJSONVALUE_COMMENT_BEFORE;
}
else if ( (m_style & wxJSONWRITER_COMMENTS_AFTER) != 0 ) {
commentPos = wxJSONVALUE_COMMENT_AFTER;
}
}
int lastChar = 0; // check if WriteComment() writes the last LF char
// first write the comment if it is BEFORE
if ( commentPos == wxJSONVALUE_COMMENT_BEFORE ) {
lastChar = WriteComment( os, value, true );
if ( lastChar < 0 ) {
return lastChar;
}
else if ( lastChar != '\n' ) {
WriteSeparator( os );
}
}
lastChar = WriteIndent( os );
if ( lastChar < 0 ) {
return lastChar;
}
// now write the key if it is not NULL
if ( key ) {
lastChar = WriteKey( os, *key );
}
if ( lastChar < 0 ) {
return lastChar;
}
// now write the value
wxJSONInternalMap::const_iterator it; // declare the map object
long int count = 0;
wxJSONType t = value.GetType();
switch ( t ) {
case wxJSONTYPE_INVALID :
WriteInvalid( os );
wxFAIL_MSG( _T("wxJSONWriter::WriteEmpty() cannot be called (not a valid JSON text"));
break;
case wxJSONTYPE_INT :
case wxJSONTYPE_SHORT :
case wxJSONTYPE_LONG :
case wxJSONTYPE_INT64 :
lastChar = WriteIntValue( os, value );
break;
case wxJSONTYPE_UINT :
case wxJSONTYPE_USHORT :
case wxJSONTYPE_ULONG :
case wxJSONTYPE_UINT64 :
lastChar = WriteUIntValue( os, value );
break;
case wxJSONTYPE_NULL :
lastChar = WriteNullValue( os );
break;
case wxJSONTYPE_BOOL :
lastChar = WriteBoolValue( os, value );
break;
case wxJSONTYPE_DOUBLE :
lastChar = WriteDoubleValue( os, value );
break;
case wxJSONTYPE_STRING :
case wxJSONTYPE_CSTRING :
lastChar = WriteStringValue( os, value.AsString());
break;
case wxJSONTYPE_MEMORYBUFF :
lastChar = WriteMemoryBuff( os, value.AsMemoryBuff());
break;
case wxJSONTYPE_ARRAY :
++m_level;
os.PutC( '[' );
// the inline comment for objects and arrays are printed in the open char
if ( commentPos == wxJSONVALUE_COMMENT_INLINE ) {
commentPos = -1; // we have already written the comment
lastChar = WriteComment( os, value, false );
if ( lastChar < 0 ) {
return lastChar;
}
if ( lastChar != '\n' ) {
lastChar = WriteSeparator( os );
}
}
else { // comment is not to be printed inline, so write a LF
lastChar = WriteSeparator( os );
if ( lastChar < 0 ) {
return lastChar;
}
}
// now iterate through all sub-items and call DoWrite() recursively
size = value.Size();
for ( int i = 0; i < size; i++ ) {
bool comma = false;
if ( i < size - 1 ) {
comma = true;
}
wxJSONValue v = value.ItemAt( i );
lastChar = DoWrite( os, v, 0, comma );
if ( lastChar < 0 ) {
return lastChar;
}
}
--m_level;
lastChar = WriteIndent( os );
if ( lastChar < 0 ) {
return lastChar;
}
os.PutC( ']' );
break;
case wxJSONTYPE_OBJECT :
++m_level;
os.PutC( '{' );
// the inline comment for objects and arrays are printed in the open char
if ( commentPos == wxJSONVALUE_COMMENT_INLINE ) {
commentPos = -1; // we have already written the comment
lastChar = WriteComment( os, value, false );
if ( lastChar < 0 ) {
return lastChar;
}
if ( lastChar != '\n' ) {
WriteSeparator( os );
}
}
else {
lastChar = WriteSeparator( os );
}
map = value.AsMap();
size = value.Size();
count = 0;
for ( it = map->begin(); it != map->end(); ++it ) {
// get the key and the value
wxString key = it->first;
const wxJSONValue& v = it->second;
bool comma = false;
if ( count < size - 1 ) {
comma = true;
}
lastChar = DoWrite( os, v, &key, comma );
if ( lastChar < 0 ) {
return lastChar;
}
count++;
}
--m_level;
lastChar = WriteIndent( os );
if ( lastChar < 0 ) {
return lastChar;
}
os.PutC( '}' );
break;
default :
// a not yet defined wxJSONType: we FAIL
wxFAIL_MSG( _T("wxJSONWriter::DoWrite() undefined wxJSONType type"));
break;
}
// writes the comma character before the inline comment
if ( comma ) {
os.PutC( ',' );
}
if ( commentPos == wxJSONVALUE_COMMENT_INLINE ) {
lastChar = WriteComment( os, value, false );
if ( lastChar < 0 ) {
return lastChar;
}
}
else if ( commentPos == wxJSONVALUE_COMMENT_AFTER ) {
WriteSeparator( os );
lastChar = WriteComment( os, value, true );
if ( lastChar < 0 ) {
return lastChar;
}
}
if ( lastChar != '\n' ) {
lastChar = WriteSeparator( os );
}
return lastChar;
}
//! Write the comment strings, if any.
int
wxJSONWriter::WriteComment( wxOutputStream& os, const wxJSONValue& value, bool indent )
{
// the function returns the last character written which should be
// a LF char or -1 in case of errors
// if nothing is written, returns ZERO
int lastChar = 0;
// only write comments if the style include the WRITE_COMMENTS flag
if ( (m_style & wxJSONWRITER_WRITE_COMMENTS ) == 0 ) {
return lastChar;
}
const wxArrayString cmt = value.GetCommentArray();
int cmtSize = cmt.GetCount();
for ( int i = 0; i < cmtSize; i++ ) {
if ( indent ) {
WriteIndent( os );
}
else {
os.PutC( '\t' );
}
WriteString( os, cmt[i]);
lastChar = cmt[i].Last();
if ( lastChar != '\n' ) {
os.PutC( '\n' );
lastChar = '\n';
}
}
return lastChar;
}
//! Writes the indentation to the JSON text.
/*!
The two functions write the indentation as \e spaces in the JSON output
text. When called with a int parameter, the function
writes the specified number of spaces.
If no parameter is given, the function computes the number of spaces
using the following formula:
If the wxJSONWRITER_TAB_INDENT flag is used in the writer's cnstructor,
the function calls WriteTabIndent().
The function also checks that wxJSONWRITER_STYLED is set and the
wxJSONWRITER_NO_INDENTATION is not set.
*/
int
wxJSONWriter::WriteIndent( wxOutputStream& os )
{
int lastChar = WriteIndent( os, m_level );
return lastChar;
}
//! Write the specified number of indentation (spaces or tabs)
/*!
The function is called by WriteIndent() and other writer's functions.
It writes the indentation as specified in the \c num parameter which is
the actual \b level of annidation.
The function checks if wxJSONWRITER_STYLED is set: if not, no indentation
is performed.
Also, the function checks if wxJSONWRITER_TAB_INDENT is set: if it is,
indentation is done by writing \b num TAB characters otherwise,
it is performed by writing a number of spaces computed as:
\code
numSpaces = m_indent + ( m_step * num )
\endcode
*/
int
wxJSONWriter::WriteIndent( wxOutputStream& os, int num )
{
int lastChar = 0;
if ( !(m_style & wxJSONWRITER_STYLED) || (m_style & wxJSONWRITER_NO_INDENTATION)) {
return lastChar;
}
int numChars = m_indent + ( m_step * num );
char c = ' ';
if ( m_style & wxJSONWRITER_TAB_INDENT ) {
c = '\t';
numChars = num;
}
for ( int i = 0; i < numChars; i++ ) {
os.PutC( c );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
}
return c;
}
//! Write the provided string to the output object.
/*!
The function writes the string \c str to the output object that
was specified in the wxJSONWriter::Write() function.
The function may split strings in two or more lines if the
string contains LF characters if the \c m_style data member contains
the wxJSONWRITER_SPLIT_STRING flag.
The function does not actually write the string: for every character
in the provided string the function calls WriteChar() which does
the actual character output.
The function returns ZERO on success or -1 in case of errors.
*/
int
wxJSONWriter::WriteStringValue( wxOutputStream& os, const wxString& str )
{
// JSON values of type STRING are written by converting the whole string
// to UTF-8 and then copying the UTF-8 buffer to the 'os' stream
// one byte at a time and processing them
os.PutC( '\"' ); // open quotes
// the buffer that has to be written is either UTF-8 or ANSI c_str() depending
// on the 'm_noUtf8' flag
char* writeBuff = 0;
wxCharBuffer utf8CB = str.ToUTF8(); // the UTF-8 buffer
#if !defined( wxJSON_USE_UNICODE )
wxCharBuffer ansiCB( str.c_str()); // the ANSI buffer
if ( m_noUtf8 ) {
writeBuff = ansiCB.data();
}
else {
writeBuff = utf8CB.data();
}
#else
writeBuff = utf8CB.data();
#endif
// NOTE: in ANSI builds UTF-8 conversion may fail (see samples/test5.cpp,
// test 7.3) although I do not know why
if ( writeBuff == 0 ) {
const char* err = "<wxJSONWriter::WriteStringValue(): error converting the string to a UTF8 buffer>";
os.Write( err, strlen( err ));
return 0;
}
size_t len = strlen( writeBuff );
int lastChar = 0;
// store the column at which the string starts
// splitting strings only happen if the string starts within
// column wxJSONWRITER_LAST_COL (default 50)
// see 'include/wx/json_defs.h' for the defines
int tempCol = m_colNo;
// now write the UTF8 buffer processing the bytes
size_t i;
for ( i = 0; i < len; i++ ) {
bool shouldEscape = false;
unsigned char ch = *writeBuff;
++writeBuff; // point to the next byte
// the escaped character
char escCh = 0;
// for every character we have to check if it is a character that
// needs to be escaped: note that characters that should be escaped
// may be not if some writer's flags are specified
switch ( ch ) {
case '\"' : // quotes
shouldEscape = true;
escCh = '\"';
break;
case '\\' : // reverse solidus
shouldEscape = true;
escCh = '\\';
break;
case '/' : // solidus
shouldEscape = true;
escCh = '/';
break;
case '\b' : // backspace
shouldEscape = true;
escCh = 'b';
break;
case '\f' : // formfeed
shouldEscape = true;
escCh = 'f';
break;
case '\n' : // newline
shouldEscape = true;
escCh = 'n';
break;
case '\r' : // carriage-return
shouldEscape = true;
escCh = 'r';
break;
case '\t' : // horizontal tab
shouldEscape = true;
escCh = 't';
break;
default :
shouldEscape = false;
break;
} // end switch
// if the character is a control character that is not identified by a
// lowercase letter, we should escape it
if ( !shouldEscape && ch < 32 ) {
char b[8];
snprintf( b, 8, "\\u%04X", (int) ch );
os.Write( b, 6 );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
}
// the char is not a control character
else {
// some characters that should be escaped are not escaped
// if the writer was constructed with some flags
if ( shouldEscape && !( m_style & wxJSONWRITER_ESCAPE_SOLIDUS) ) {
if ( ch == '/' ) {
shouldEscape = false;
}
}
if ( shouldEscape && (m_style & wxJSONWRITER_MULTILINE_STRING)) {
if ( ch == '\n' || ch == '\t' ) {
shouldEscape = false;
}
}
// now write the character prepended by ESC if it should be escaped
if ( shouldEscape ) {
os.PutC( '\\' );
os.PutC( escCh );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
}
else {
// a normal char or a UTF-8 units: write the character
os.PutC( ch );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
}
}
// check if SPLIT_STRING flag is set and if the string has to
// be splitted
if ( (m_style & wxJSONWRITER_STYLED) && (m_style & wxJSONWRITER_SPLIT_STRING)) {
// split the string if the character written is LF
if ( ch == '\n' ) {
// close quotes and CR
os.Write( "\"\n", 2 );
lastChar = WriteIndent( os, m_level + 2 ); // write indentation
os.PutC( '\"' ); // reopen quotes
if ( lastChar < 0 ) {
return lastChar;
}
}
// split the string only if there is at least wxJSONWRITER_MIN_LENGTH
// character to write and the character written is a punctuation or space
// BUG: the following does not work because the columns are not counted
else if ( (m_colNo >= wxJSONWRITER_SPLIT_COL)
&& (tempCol <= wxJSONWRITER_LAST_COL )) {
if ( IsSpace( ch ) || IsPunctuation( ch )) {
if ( len - i > wxJSONWRITER_MIN_LENGTH ) {
// close quotes and CR
os.Write( "\"\n", 2 );
lastChar = WriteIndent( os, m_level + 2 ); // write indentation
os.PutC( '\"' ); // reopen quotes
if ( lastChar < 0 ) {
return lastChar;
}
}
}
}
}
} // end for
os.PutC( '\"' ); // close quotes
return 0;
}
//! Write a generic string
/*!
The function writes the wxString object \c str to the output object.
The string is written as is; you cannot use it to write JSON strings
to the output text.
The function converts the string \c str to UTF-8 and writes the buffer..
*/
int
wxJSONWriter::WriteString( wxOutputStream& os, const wxString& str )
{
wxLogTrace( writerTraceMask, _T("(%s) string to write=%s"),
__PRETTY_FUNCTION__, str.c_str() );
int lastChar = 0;
char* writeBuff = 0;
// the buffer that has to be written is either UTF-8 or ANSI c_str() depending
// on the 'm_noUtf8' flag
wxCharBuffer utf8CB = str.ToUTF8(); // the UTF-8 buffer
#if !defined( wxJSON_USE_UNICODE )
wxCharBuffer ansiCB( str.c_str()); // the ANSI buffer
if ( m_noUtf8 ) {
writeBuff = ansiCB.data();
}
else {
writeBuff = utf8CB.data();
}
#else
writeBuff = utf8CB.data();
#endif
// NOTE: in ANSI builds UTF-8 conversion may fail (see samples/test5.cpp,
// test 7.3) although I do not know why
if ( writeBuff == 0 ) {
const char* err = "<wxJSONWriter::WriteComment(): error converting the string to UTF-8>";
os.Write( err, strlen( err ));
return 0;
}
size_t len = strlen( writeBuff );
os.Write( writeBuff, len );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
wxLogTrace( writerTraceMask, _T("(%s) result=%d"),
__PRETTY_FUNCTION__, lastChar );
return lastChar;
}
//! Write the NULL JSON value to the output stream.
/*!
The function writes the \b null literal string to the output stream.
*/
int
wxJSONWriter::WriteNullValue( wxOutputStream& os )
{
os.Write( "null", 4 );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
return 0;
}
//! Writes a value of type INT.
/*!
This function is called for every value objects of INT type.
This function uses the \n snprintf function to get the US-ASCII
representation of the integer and simply copy it to the output stream.
Returns -1 on stream errors or ZERO if no errors.
*/
int
wxJSONWriter::WriteIntValue( wxOutputStream& os, const wxJSONValue& value )
{
int r = 0;
char buffer[32]; // need to store 64-bits integers (max 20 digits)
size_t len;
wxJSONRefData* data = value.GetRefData();
wxASSERT( data );
#if defined( wxJSON_64BIT_INT )
#if wxCHECK_VERSION(2, 9, 0 ) || !defined( wxJSON_USE_UNICODE )
// this is fine for wxW 2.9 and for wxW 2.8 ANSI
snprintf( buffer, 32, "%" wxLongLongFmtSpec "d",
data->m_value.m_valInt64 );
#else
// this is for wxW 2.8 Unicode: in order to use the cross-platform
// format specifier, we use the wxString's sprintf() function and then
// convert to UTF-8 before writing to the stream
wxString s;
s.Printf( _T("%") wxLongLongFmtSpec _T("d"),
data->m_value.m_valInt64 );
wxCharBuffer cb = s.ToUTF8();
const char* cbData = cb.data();
len = strlen( cbData );
wxASSERT( len < 32 );
memcpy( buffer, cbData, len );
buffer[len] = 0;
#endif
#else
snprintf( buffer, 32, "%ld", data->m_value.m_valLong );
#endif
len = strlen( buffer );
os.Write( buffer, len );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
r = -1;
}
return r;
}
//! Writes a value of type UNSIGNED INT.
/*!
This function is called for every value objects of UINT type.
This function uses the \n snprintf function to get the US-ASCII
representation of the integer and simply copy it to the output stream.
The function prepends a \b plus \b sign if the \c wxJSONWRITER_RECOGNIZE_UNSIGNED
flag is set in the \c m_flags data member.
Returns -1 on stream errors or ZERO if no errors.
*/
int
wxJSONWriter::WriteUIntValue( wxOutputStream& os, const wxJSONValue& value )
{
int r = 0; size_t len;
// prepend a plus sign if the style specifies that unsigned integers
// have to be recognized by the JSON reader
if ( m_style & wxJSONWRITER_RECOGNIZE_UNSIGNED ) {
os.PutC( '+' );
}
char buffer[32]; // need to store 64-bits integers (max 20 digits)
wxJSONRefData* data = value.GetRefData();
wxASSERT( data );
#if defined( wxJSON_64BIT_INT )
#if wxCHECK_VERSION(2, 9, 0 ) || !defined( wxJSON_USE_UNICODE )
// this is fine for wxW 2.9 and for wxW 2.8 ANSI
snprintf( buffer, 32, "%" wxLongLongFmtSpec "u",
data->m_value.m_valUInt64 );
#else
// this is for wxW 2.8 Unicode: in order to use the cross-platform
// format specifier, we use the wxString's sprintf() function and then
// convert to UTF-8 before writing to the stream
wxString s;
s.Printf( _T("%") wxLongLongFmtSpec _T("u"),
data->m_value.m_valInt64 );
wxCharBuffer cb = s.ToUTF8();
const char* cbData = cb.data();
len = strlen( cbData );
wxASSERT( len < 32 );
memcpy( buffer, cbData, len );
buffer[len] = 0;
#endif
#else
snprintf( buffer, 32, "%lu", data->m_value.m_valULong );
#endif
len = strlen( buffer );
os.Write( buffer, len );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
r = -1;
}
return r;
}
//! Writes a value of type DOUBLE.
/*!
This function is called for every value objects of DOUBLE type.
This function uses the \n snprintf function to get the US-ASCII
representation of the integer and simply copy it to the output stream.
Returns -1 on stream errors or ZERO if no errors.
Note that writing a double to a decimal ASCII representation could
lay to unexpected results depending on the format string used in the
conversion.
See SetDoubleFmtString for details.
*/
int
wxJSONWriter::WriteDoubleValue( wxOutputStream& os, const wxJSONValue& value )
{
int r = 0;
char buffer[32];
wxJSONRefData* data = value.GetRefData();
wxASSERT( data );
snprintf( buffer, 32, m_fmt, data->m_value.m_valDouble );
size_t len = strlen( buffer );
os.Write( buffer, len );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
r = -1;
}
return r;
}
//! Writes a value of type BOOL.
/*!
This function is called for every value objects of BOOL type.
This function prints the literals \b true or \b false depending on the
value in \c value.
Returns -1 on stream errors or ZERO if no errors.
*/
int
wxJSONWriter::WriteBoolValue( wxOutputStream& os, const wxJSONValue& value )
{
int r = 0;
const char* f = "false"; const char* t = "true";
wxJSONRefData* data = value.GetRefData();
wxASSERT( data );
const char* c = f; // defaults to FALSE
if ( data->m_value.m_valBool ) {
c = t;
}
size_t len = strlen( c );
os.Write( c, len );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
r = -1;
}
return r;
}
//! Write the key of a key/value element to the output stream.
int
wxJSONWriter::WriteKey( wxOutputStream& os, const wxString& key )
{
wxLogTrace( writerTraceMask, _T("(%s) key write=%s"),
__PRETTY_FUNCTION__, key.c_str() );
int lastChar = WriteStringValue( os, key );
os.Write( " : ", 3 );
return lastChar;
}
//! Write the invalid JSON value to the output stream.
/*!
An invalid wxJSONValue is a value that was not initialized and it is
an error. You should never write invalid values to JSON text because
the output is not valid JSON text.
Note that the NULL value is a legal JSON text and it is written:
\code
null
\endcode
This function writes a non-JSON text to the output stream:
\code
<invalid JSON value>
\endcode
In debug mode, the function always fails with an wxFAIL_MSG failure.
*/
int
wxJSONWriter::WriteInvalid( wxOutputStream& os )
{
wxFAIL_MSG( _T("wxJSONWriter::WriteInvalid() cannot be called (not a valid JSON text"));
int lastChar = 0;
os.Write( "<invalid JSON value>", 9 );
return lastChar;
}
//! Write a JSON value of type \e memory \e buffer
/*!
The type wxJSONTYPE_MEMORYBUFF is a \b wxJSON extension that is not correctly read by
other JSON implementations.
By default, the function writes such a type as an array of INTs as follows:
\code
[ 0,32,45,255,6,...]
\endcode
If the writer object was constructed using the \c wxJSONWRITER_MEMORYBUFF flag, then
the output is much more compact and recognized by the \b wxJSON reader as a memory buffer
type:
\code
'00203FFF06..'
\endcode
*/
int
wxJSONWriter::WriteMemoryBuff( wxOutputStream& os, const wxMemoryBuffer& buff )
{
#define MAX_BYTES_PER_ROW 20
char str[16];
// if STYLED and SPLIT_STRING flags are set, the function writes 20 bytes on every row
// the following is the counter of bytes written.
// the string is splitted only for the special meory buffer type, not for array of INTs
int bytesWritten = 0;
bool splitString = false;
if ( (m_style & wxJSONWRITER_STYLED) &&
(m_style & wxJSONWRITER_SPLIT_STRING)) {
splitString = true;
}
size_t buffLen = buff.GetDataLen();
unsigned char* ptr = (unsigned char*) buff.GetData();
wxASSERT( ptr );
char openChar = '\'';
char closeChar = '\'';
bool asArray = false;
if ( (m_style & wxJSONWRITER_MEMORYBUFF ) == 0 ) {
// if the special flag is not specified, write as an array of INTs
openChar = '[';
closeChar = ']';
asArray = true;
}
// write the open character
os.PutC( openChar );
for ( size_t i = 0; i < buffLen; i++ ) {
unsigned char c = *ptr;
++ptr;
if ( asArray ) {
snprintf( str, 14, "%d", c );
size_t len = strlen( str );
wxASSERT( len <= 3 );
wxASSERT( len >= 1 );
str[len] = ',';
// do not write the comma char for the last element
if ( i < buffLen - 1 ) {
++len;
}
os.Write( str, len );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
}
else {
// now convert the byte in two hex digits
char c1 = c / 16;
char c2 = c % 16;
c1 += '0';
c2 += '0';
if ( c1 > '9' ) {
c1 += 7;
}
if ( c2 > '9' ) {
c2 += 7;
}
os.PutC( c1 );
os.PutC( c2 );
if ( os.GetLastError() != wxSTREAM_NO_ERROR ) {
return -1;
}
if ( splitString ) {
++bytesWritten;
}
if (( bytesWritten >= MAX_BYTES_PER_ROW ) && ((buffLen - i ) >= 5 )) {
// split the string if we wrote 20 bytes, but only is we have to
// write at least 5 bytes
os.Write( "\'\n", 2 );
int lastChar = WriteIndent( os, m_level + 2 ); // write indentation
os.PutC( '\'' ); // reopen quotes
if ( lastChar < 0 ) {
return lastChar;
}
bytesWritten = 0;
}
}
}
// write the close character
os.PutC( closeChar );
return closeChar;
}
//! Writes the separator between values
/*!
The function is called when a value has been written to the JSON
text output and it writes the separator character: LF.
The LF char is actually written only if the wxJSONWRITER_STYLED flag
is specified and wxJSONWRITER_NO_LINEFEEDS is not set.
Returns the last character written which is LF itself or -1 in case
of errors. Note that LF is returned even if the character is not
actually written.
*/
int
wxJSONWriter::WriteSeparator( wxOutputStream& os )
{
int lastChar = '\n';
if ( (m_style & wxJSONWRITER_STYLED) && !(m_style & wxJSONWRITER_NO_LINEFEEDS )) {
os.PutC( '\n' );
}
return lastChar;
}
//! Returns TRUE if the character is a space character.
bool
wxJSONWriter::IsSpace( wxChar ch )
{
bool r = false;
switch ( ch ) {
case ' ' :
case '\t' :
case '\r' :
case '\f' :
case '\n' :
r = true;
break;
default :
break;
}
return r;
}
//! Returns TRUE if the character if a puctuation character
bool
wxJSONWriter::IsPunctuation( wxChar ch )
{
bool r = false;
switch ( ch ) {
case '.' :
case ',' :
case ';' :
case ':' :
case '!' :
case '?' :
r = true;
break;
default :
break;
}
return r;
}
/*
{
}
*/