mirror of
https://github.com/transmission/transmission
synced 2024-12-30 11:36:07 +00:00
778 lines
24 KiB
C
778 lines
24 KiB
C
/*
|
|
* Copyright 2001-2004 Unicode, Inc.
|
|
*
|
|
* Disclaimer
|
|
*
|
|
* This source code is provided as is by Unicode, Inc. No claims are
|
|
* made as to fitness for any particular purpose. No warranties of any
|
|
* kind are expressed or implied. The recipient agrees to determine
|
|
* applicability of information provided. If this file has been
|
|
* purchased on magnetic or optical media from Unicode, Inc., the
|
|
* sole remedy for any claim will be exchange of defective media
|
|
* within 90 days of receipt.
|
|
*
|
|
* Limitations on Rights to Redistribute This Code
|
|
*
|
|
* Unicode, Inc. hereby grants the right to freely use the information
|
|
* supplied in this file in the creation of products supporting the
|
|
* Unicode Standard, and to make copies of this file in any form
|
|
* for internal or external distribution as long as this notice
|
|
* remains attached.
|
|
*/
|
|
|
|
/* ---------------------------------------------------------------------
|
|
|
|
Conversions between UTF32, UTF-16, and UTF-8. Source code file.
|
|
Author: Mark E. Davis, 1994.
|
|
Rev History: Rick McGowan, fixes & updates May 2001.
|
|
Sept 2001: fixed const & error conditions per
|
|
mods suggested by S. Parent & A. Lillich.
|
|
June 2002: Tim Dodd added detection and handling of incomplete
|
|
source sequences, enhanced error detection, added casts
|
|
to eliminate compiler warnings.
|
|
July 2003: slight mods to back out aggressive FFFE detection.
|
|
Jan 2004: updated switches in from-UTF8 conversions.
|
|
Oct 2004: updated to use UNI_MAX_LEGAL_UTF32 in UTF-32 conversions.
|
|
|
|
See the header file "ConvertUTF.h" for complete documentation.
|
|
|
|
------------------------------------------------------------------------ */
|
|
|
|
|
|
#include "ConvertUTF.h"
|
|
#ifdef CVTUTF_DEBUG
|
|
#include <stdio.h>
|
|
#endif
|
|
|
|
static const int halfShift = 10; /* used for shifting by 10 bits */
|
|
|
|
static const UTF32 halfBase = 0x0010000UL;
|
|
static const UTF32 halfMask = 0x3FFUL;
|
|
|
|
#define UNI_SUR_HIGH_START (UTF32)0xD800
|
|
#define UNI_SUR_HIGH_END (UTF32)0xDBFF
|
|
#define UNI_SUR_LOW_START (UTF32)0xDC00
|
|
#define UNI_SUR_LOW_END (UTF32)0xDFFF
|
|
#define false 0
|
|
#define true 1
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
ConversionResult
|
|
ConvertUTF32toUTF16( const UTF32** sourceStart,
|
|
const UTF32* sourceEnd,
|
|
UTF16** targetStart,
|
|
UTF16* targetEnd,
|
|
ConversionFlags flags )
|
|
{
|
|
ConversionResult result = conversionOK;
|
|
const UTF32* source = *sourceStart;
|
|
UTF16* target = *targetStart;
|
|
|
|
while( source < sourceEnd )
|
|
{
|
|
UTF32 ch;
|
|
if( target >= targetEnd )
|
|
{
|
|
result = targetExhausted; break;
|
|
}
|
|
ch = *source++;
|
|
if( ch <= UNI_MAX_BMP ) /* Target is a character <= 0xFFFF */
|
|
{ /* UTF-16 surrogate values are illegal in UTF-32; 0xffff or 0xfffe are
|
|
both reserved values */
|
|
if( ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END )
|
|
{
|
|
if( flags == strictConversion )
|
|
{
|
|
--source; /* return to the illegal value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
else
|
|
{
|
|
*target++ = UNI_REPLACEMENT_CHAR;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
*target++ = (UTF16)ch; /* normal case */
|
|
}
|
|
}
|
|
else if( ch > UNI_MAX_LEGAL_UTF32 )
|
|
{
|
|
if( flags == strictConversion )
|
|
{
|
|
result = sourceIllegal;
|
|
}
|
|
else
|
|
{
|
|
*target++ = UNI_REPLACEMENT_CHAR;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* target is a character in range 0xFFFF - 0x10FFFF. */
|
|
if( target + 1 >= targetEnd )
|
|
{
|
|
--source; /* Back up source pointer! */
|
|
result = targetExhausted; break;
|
|
}
|
|
ch -= halfBase;
|
|
*target++ = (UTF16)( ( ch >> halfShift ) + UNI_SUR_HIGH_START );
|
|
*target++ = (UTF16)( ( ch & halfMask ) + UNI_SUR_LOW_START );
|
|
}
|
|
}
|
|
|
|
*sourceStart = source;
|
|
*targetStart = target;
|
|
return result;
|
|
}
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
ConversionResult
|
|
ConvertUTF16toUTF32( const UTF16** sourceStart,
|
|
const UTF16* sourceEnd,
|
|
UTF32** targetStart,
|
|
UTF32* targetEnd,
|
|
ConversionFlags flags )
|
|
{
|
|
ConversionResult result = conversionOK;
|
|
const UTF16* source = *sourceStart;
|
|
UTF32* target = *targetStart;
|
|
UTF32 ch, ch2;
|
|
|
|
while( source < sourceEnd )
|
|
{
|
|
const UTF16* oldSource = source; /* In case we have to back up because
|
|
of target overflow. */
|
|
ch = *source++;
|
|
/* If we have a surrogate pair, convert to UTF32 first. */
|
|
if( ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END )
|
|
{
|
|
/* If the 16 bits following the high surrogate are in the source
|
|
buffer... */
|
|
if( source < sourceEnd )
|
|
{
|
|
ch2 = *source;
|
|
/* If it's a low surrogate, convert to UTF32. */
|
|
if( ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END )
|
|
{
|
|
ch = ( ( ch - UNI_SUR_HIGH_START ) << halfShift )
|
|
+ ( ch2 - UNI_SUR_LOW_START ) + halfBase;
|
|
++source;
|
|
}
|
|
else if( flags == strictConversion ) /* it's an unpaired high
|
|
surrogate */
|
|
{
|
|
--source; /* return to the illegal value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
}
|
|
else /* We don't have the 16 bits following the high surrogate. */
|
|
{
|
|
--source; /* return to the high surrogate */
|
|
result = sourceExhausted;
|
|
break;
|
|
}
|
|
}
|
|
else if( flags == strictConversion )
|
|
{
|
|
/* UTF-16 surrogate values are illegal in UTF-32 */
|
|
if( ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END )
|
|
{
|
|
--source; /* return to the illegal value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
}
|
|
if( target >= targetEnd )
|
|
{
|
|
source = oldSource; /* Back up source pointer! */
|
|
result = targetExhausted; break;
|
|
}
|
|
*target++ = ch;
|
|
}
|
|
|
|
*sourceStart = source;
|
|
*targetStart = target;
|
|
#ifdef CVTUTF_DEBUG
|
|
if( result == sourceIllegal )
|
|
{
|
|
fprintf( stderr, "ConvertUTF16toUTF32 illegal seq 0x%04x,%04x\n",
|
|
ch,
|
|
ch2 );
|
|
fflush( stderr );
|
|
}
|
|
#endif
|
|
return result;
|
|
}
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* Index into the table below with the first byte of a UTF-8 sequence to
|
|
* get the number of trailing bytes that are supposed to follow it.
|
|
* Note that *legal* UTF-8 values can't have 4 or 5-bytes. The table is
|
|
* left as-is for anyone who may want to do such conversion, which was
|
|
* allowed in earlier algorithms.
|
|
*/
|
|
static const char trailingBytesForUTF8[256] = {
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
|
0, 0, 0, 0, 0, 0, 0, 0,
|
|
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
|
|
1, 1, 1, 1, 1, 1, 1, 1,
|
|
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3,
|
|
4, 4, 4, 4, 5, 5, 5, 5
|
|
};
|
|
|
|
/*
|
|
* Magic values subtracted from a buffer value during UTF8 conversion.
|
|
* This table contains as many values as there might be trailing bytes
|
|
* in a UTF-8 sequence.
|
|
*/
|
|
static const UTF32 offsetsFromUTF8[6] =
|
|
{ 0x00000000UL, 0x00003080UL,
|
|
0x000E2080UL,
|
|
0x03C82080UL, 0xFA082080UL,
|
|
0x82082080UL };
|
|
|
|
/*
|
|
* Once the bits are split out into bytes of UTF-8, this is a mask OR-ed
|
|
* into the first byte, depending on how many bytes follow. There are
|
|
* as many entries in this table as there are UTF-8 sequence types.
|
|
* (I.e., one byte sequence, two byte... etc.). Remember that sequencs
|
|
* for *legal* UTF-8 will be 4 or fewer bytes total.
|
|
*/
|
|
static const UTF8 firstByteMark[7] =
|
|
{ 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
/* The interface converts a whole buffer to avoid function-call overhead.
|
|
* Constants have been gathered. Loops & conditionals have been removed as
|
|
* much as possible for efficiency, in favor of drop-through switches.
|
|
* (See "Note A" at the bottom of the file for equivalent code.)
|
|
* If your compiler supports it, the "isLegalUTF8" call can be turned
|
|
* into an inline function.
|
|
*/
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
ConversionResult
|
|
ConvertUTF16toUTF8( const UTF16** sourceStart,
|
|
const UTF16* sourceEnd,
|
|
UTF8** targetStart,
|
|
UTF8* targetEnd,
|
|
ConversionFlags flags )
|
|
{
|
|
ConversionResult result = conversionOK;
|
|
const UTF16* source = *sourceStart;
|
|
UTF8* target = *targetStart;
|
|
|
|
while( source < sourceEnd )
|
|
{
|
|
UTF32 ch;
|
|
unsigned short bytesToWrite = 0;
|
|
const UTF32 byteMask = 0xBF;
|
|
const UTF32 byteMark = 0x80;
|
|
const UTF16* oldSource = source; /* In case we have to back up because
|
|
of target overflow. */
|
|
ch = *source++;
|
|
/* If we have a surrogate pair, convert to UTF32 first. */
|
|
if( ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END )
|
|
{
|
|
/* If the 16 bits following the high surrogate are in the source
|
|
buffer... */
|
|
if( source < sourceEnd )
|
|
{
|
|
UTF32 ch2 = *source;
|
|
/* If it's a low surrogate, convert to UTF32. */
|
|
if( ch2 >= UNI_SUR_LOW_START && ch2 <= UNI_SUR_LOW_END )
|
|
{
|
|
ch = ( ( ch - UNI_SUR_HIGH_START ) << halfShift )
|
|
+ ( ch2 - UNI_SUR_LOW_START ) + halfBase;
|
|
++source;
|
|
}
|
|
else if( flags == strictConversion ) /* it's an unpaired high
|
|
surrogate */
|
|
{
|
|
--source; /* return to the illegal value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
}
|
|
else /* We don't have the 16 bits following the high surrogate. */
|
|
{
|
|
--source; /* return to the high surrogate */
|
|
result = sourceExhausted;
|
|
break;
|
|
}
|
|
}
|
|
else if( flags == strictConversion )
|
|
{
|
|
/* UTF-16 surrogate values are illegal in UTF-32 */
|
|
if( ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END )
|
|
{
|
|
--source; /* return to the illegal value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
}
|
|
/* Figure out how many bytes the result will require */
|
|
if( ch < (UTF32)0x80 )
|
|
{
|
|
bytesToWrite = 1;
|
|
}
|
|
else if( ch < (UTF32)0x800 )
|
|
{
|
|
bytesToWrite = 2;
|
|
}
|
|
else if( ch < (UTF32)0x10000 )
|
|
{
|
|
bytesToWrite = 3;
|
|
}
|
|
else if( ch < (UTF32)0x110000 )
|
|
{
|
|
bytesToWrite = 4;
|
|
}
|
|
else
|
|
{
|
|
bytesToWrite = 3;
|
|
ch = UNI_REPLACEMENT_CHAR;
|
|
}
|
|
|
|
target += bytesToWrite;
|
|
if( target > targetEnd )
|
|
{
|
|
source = oldSource; /* Back up source pointer! */
|
|
target -= bytesToWrite; result = targetExhausted; break;
|
|
}
|
|
switch( bytesToWrite ) /* note: everything falls through. */
|
|
{
|
|
case 4:
|
|
*--target =
|
|
(UTF8)( ( ch | byteMark ) & byteMask ); ch >>= 6;
|
|
|
|
case 3:
|
|
*--target =
|
|
(UTF8)( ( ch | byteMark ) & byteMask ); ch >>= 6;
|
|
|
|
case 2:
|
|
*--target =
|
|
(UTF8)( ( ch | byteMark ) & byteMask ); ch >>= 6;
|
|
|
|
case 1:
|
|
*--target = (UTF8)( ch | firstByteMark[bytesToWrite] );
|
|
}
|
|
target += bytesToWrite;
|
|
}
|
|
|
|
*sourceStart = source;
|
|
*targetStart = target;
|
|
return result;
|
|
}
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* Utility routine to tell whether a sequence of bytes is legal UTF-8.
|
|
* This must be called with the length pre-determined by the first byte.
|
|
* If not calling this from ConvertUTF8to*, then the length can be set by:
|
|
* length = trailingBytesForUTF8[*source]+1;
|
|
* and the sequence is illegal right away if there aren't that many bytes
|
|
* available.
|
|
* If presented with a length > 4, this returns false. The Unicode
|
|
* definition of UTF-8 goes up to 4-byte sequences.
|
|
*/
|
|
|
|
static Boolean
|
|
isLegalUTF8( const UTF8 *source,
|
|
int length )
|
|
{
|
|
UTF8 a;
|
|
const UTF8 *srcptr = source + length;
|
|
|
|
switch( length )
|
|
{
|
|
default:
|
|
return false;
|
|
|
|
/* Everything else falls through when "true"... */
|
|
case 4:
|
|
if( ( a = ( *--srcptr ) ) < 0x80 || a > 0xBF ) return false;
|
|
|
|
case 3:
|
|
if( ( a = ( *--srcptr ) ) < 0x80 || a > 0xBF ) return false;
|
|
|
|
case 2:
|
|
if( ( a = ( *--srcptr ) ) > 0xBF ) return false;
|
|
|
|
switch( *source )
|
|
{
|
|
/* no fall-through in this inner switch */
|
|
case 0xE0:
|
|
if( a < 0xA0 ) return false;break;
|
|
|
|
case 0xED:
|
|
if( a > 0x9F ) return false;break;
|
|
|
|
case 0xF0:
|
|
if( a < 0x90 ) return false;break;
|
|
|
|
case 0xF4:
|
|
if( a > 0x8F ) return false;break;
|
|
|
|
default:
|
|
if( a < 0x80 ) return false;
|
|
}
|
|
|
|
case 1:
|
|
if( *source >= 0x80 && *source < 0xC2 ) return false;
|
|
}
|
|
if( *source > 0xF4 ) return false;
|
|
return true;
|
|
}
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* Exported function to return whether a UTF-8 sequence is legal or not.
|
|
* This is not used here; it's just exported.
|
|
*/
|
|
Boolean
|
|
isLegalUTF8Sequence( const UTF8 *source,
|
|
const UTF8 *sourceEnd )
|
|
{
|
|
int length = trailingBytesForUTF8[*source] + 1;
|
|
|
|
if( source + length > sourceEnd )
|
|
{
|
|
return false;
|
|
}
|
|
return isLegalUTF8( source, length );
|
|
}
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
ConversionResult
|
|
ConvertUTF8toUTF16( const UTF8** sourceStart,
|
|
const UTF8* sourceEnd,
|
|
UTF16** targetStart,
|
|
UTF16* targetEnd,
|
|
ConversionFlags flags )
|
|
{
|
|
ConversionResult result = conversionOK;
|
|
const UTF8* source = *sourceStart;
|
|
UTF16* target = *targetStart;
|
|
|
|
while( source < sourceEnd )
|
|
{
|
|
UTF32 ch = 0;
|
|
unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
|
|
if( source + extraBytesToRead >= sourceEnd )
|
|
{
|
|
result = sourceExhausted; break;
|
|
}
|
|
/* Do this check whether lenient or strict */
|
|
if( !isLegalUTF8( source, extraBytesToRead + 1 ) )
|
|
{
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
/*
|
|
* The cases all fall through. See "Note A" below.
|
|
*/
|
|
switch( extraBytesToRead )
|
|
{
|
|
case 5:
|
|
ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
|
|
|
|
case 4:
|
|
ch += *source++; ch <<= 6; /* remember, illegal UTF-8 */
|
|
|
|
case 3:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 2:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 1:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 0:
|
|
ch += *source++;
|
|
}
|
|
ch -= offsetsFromUTF8[extraBytesToRead];
|
|
|
|
if( target >= targetEnd )
|
|
{
|
|
source -= ( extraBytesToRead + 1 ); /* Back up source pointer! */
|
|
result = targetExhausted; break;
|
|
}
|
|
if( ch <= UNI_MAX_BMP ) /* Target is a character <= 0xFFFF */
|
|
{ /* UTF-16 surrogate values are illegal in UTF-32 */
|
|
if( ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END )
|
|
{
|
|
if( flags == strictConversion )
|
|
{
|
|
source -= ( extraBytesToRead + 1 ); /* return to the illegal
|
|
value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
else
|
|
{
|
|
*target++ = UNI_REPLACEMENT_CHAR;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
*target++ = (UTF16)ch; /* normal case */
|
|
}
|
|
}
|
|
else if( ch > UNI_MAX_UTF16 )
|
|
{
|
|
if( flags == strictConversion )
|
|
{
|
|
result = sourceIllegal;
|
|
source -= ( extraBytesToRead + 1 ); /* return to the start */
|
|
break; /* Bail out; shouldn't continue */
|
|
}
|
|
else
|
|
{
|
|
*target++ = UNI_REPLACEMENT_CHAR;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* target is a character in range 0xFFFF - 0x10FFFF. */
|
|
if( target + 1 >= targetEnd )
|
|
{
|
|
source -= ( extraBytesToRead + 1 ); /* Back up source pointer!
|
|
*/
|
|
result = targetExhausted; break;
|
|
}
|
|
ch -= halfBase;
|
|
*target++ = (UTF16)( ( ch >> halfShift ) + UNI_SUR_HIGH_START );
|
|
*target++ = (UTF16)( ( ch & halfMask ) + UNI_SUR_LOW_START );
|
|
}
|
|
}
|
|
|
|
*sourceStart = source;
|
|
*targetStart = target;
|
|
return result;
|
|
}
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
ConversionResult
|
|
ConvertUTF32toUTF8( const UTF32** sourceStart,
|
|
const UTF32* sourceEnd,
|
|
UTF8** targetStart,
|
|
UTF8* targetEnd,
|
|
ConversionFlags flags )
|
|
{
|
|
ConversionResult result = conversionOK;
|
|
const UTF32* source = *sourceStart;
|
|
UTF8* target = *targetStart;
|
|
|
|
while( source < sourceEnd )
|
|
{
|
|
UTF32 ch;
|
|
unsigned short bytesToWrite = 0;
|
|
const UTF32 byteMask = 0xBF;
|
|
const UTF32 byteMark = 0x80;
|
|
ch = *source++;
|
|
if( flags == strictConversion )
|
|
{
|
|
/* UTF-16 surrogate values are illegal in UTF-32 */
|
|
if( ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END )
|
|
{
|
|
--source; /* return to the illegal value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
}
|
|
/*
|
|
* Figure out how many bytes the result will require. Turn any
|
|
* illegally large UTF32 things (> Plane 17) into replacement chars.
|
|
*/
|
|
if( ch < (UTF32)0x80 )
|
|
{
|
|
bytesToWrite = 1;
|
|
}
|
|
else if( ch < (UTF32)0x800 )
|
|
{
|
|
bytesToWrite = 2;
|
|
}
|
|
else if( ch < (UTF32)0x10000 )
|
|
{
|
|
bytesToWrite = 3;
|
|
}
|
|
else if( ch <= UNI_MAX_LEGAL_UTF32 )
|
|
{
|
|
bytesToWrite = 4;
|
|
}
|
|
else
|
|
{
|
|
bytesToWrite = 3;
|
|
ch = UNI_REPLACEMENT_CHAR;
|
|
result = sourceIllegal;
|
|
}
|
|
|
|
target += bytesToWrite;
|
|
if( target > targetEnd )
|
|
{
|
|
--source; /* Back up source pointer! */
|
|
target -= bytesToWrite; result = targetExhausted; break;
|
|
}
|
|
switch( bytesToWrite ) /* note: everything falls through. */
|
|
{
|
|
case 4:
|
|
*--target =
|
|
(UTF8)( ( ch | byteMark ) & byteMask ); ch >>= 6;
|
|
|
|
case 3:
|
|
*--target =
|
|
(UTF8)( ( ch | byteMark ) & byteMask ); ch >>= 6;
|
|
|
|
case 2:
|
|
*--target =
|
|
(UTF8)( ( ch | byteMark ) & byteMask ); ch >>= 6;
|
|
|
|
case 1:
|
|
*--target = (UTF8) ( ch | firstByteMark[bytesToWrite] );
|
|
}
|
|
target += bytesToWrite;
|
|
}
|
|
|
|
*sourceStart = source;
|
|
*targetStart = target;
|
|
return result;
|
|
}
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
ConversionResult
|
|
ConvertUTF8toUTF32( const UTF8** sourceStart,
|
|
const UTF8* sourceEnd,
|
|
UTF32** targetStart,
|
|
UTF32* targetEnd,
|
|
ConversionFlags flags )
|
|
{
|
|
ConversionResult result = conversionOK;
|
|
const UTF8* source = *sourceStart;
|
|
UTF32* target = *targetStart;
|
|
|
|
while( source < sourceEnd )
|
|
{
|
|
UTF32 ch = 0;
|
|
unsigned short extraBytesToRead = trailingBytesForUTF8[*source];
|
|
if( source + extraBytesToRead >= sourceEnd )
|
|
{
|
|
result = sourceExhausted; break;
|
|
}
|
|
/* Do this check whether lenient or strict */
|
|
if( !isLegalUTF8( source, extraBytesToRead + 1 ) )
|
|
{
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
/*
|
|
* The cases all fall through. See "Note A" below.
|
|
*/
|
|
switch( extraBytesToRead )
|
|
{
|
|
case 5:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 4:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 3:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 2:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 1:
|
|
ch += *source++; ch <<= 6;
|
|
|
|
case 0:
|
|
ch += *source++;
|
|
}
|
|
ch -= offsetsFromUTF8[extraBytesToRead];
|
|
|
|
if( target >= targetEnd )
|
|
{
|
|
source -= ( extraBytesToRead + 1 ); /* Back up the source pointer!
|
|
*/
|
|
result = targetExhausted; break;
|
|
}
|
|
if( ch <= UNI_MAX_LEGAL_UTF32 )
|
|
{
|
|
/*
|
|
* UTF-16 surrogate values are illegal in UTF-32, and anything
|
|
* over Plane 17 (> 0x10FFFF) is illegal.
|
|
*/
|
|
if( ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_LOW_END )
|
|
{
|
|
if( flags == strictConversion )
|
|
{
|
|
source -= ( extraBytesToRead + 1 ); /* return to the illegal
|
|
value itself */
|
|
result = sourceIllegal;
|
|
break;
|
|
}
|
|
else
|
|
{
|
|
*target++ = UNI_REPLACEMENT_CHAR;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
*target++ = ch;
|
|
}
|
|
}
|
|
else /* i.e., ch > UNI_MAX_LEGAL_UTF32 */
|
|
{
|
|
result = sourceIllegal;
|
|
*target++ = UNI_REPLACEMENT_CHAR;
|
|
}
|
|
}
|
|
|
|
*sourceStart = source;
|
|
*targetStart = target;
|
|
return result;
|
|
}
|
|
|
|
/* ---------------------------------------------------------------------
|
|
|
|
Note A.
|
|
The fall-through switches in UTF-8 reading code save a
|
|
temp variable, some decrements & conditionals. The switches
|
|
are equivalent to the following loop:
|
|
{
|
|
int tmpBytesToRead = extraBytesToRead+1;
|
|
do {
|
|
ch += *source++;
|
|
--tmpBytesToRead;
|
|
if (tmpBytesToRead) ch <<= 6;
|
|
} while (tmpBytesToRead > 0);
|
|
}
|
|
In UTF-8 writing code, the switches on "bytesToWrite" are
|
|
similarly unrolled loops.
|
|
|
|
--------------------------------------------------------------------- */
|