#include "UTF8.h"
namespace WTF {
namespace Unicode {
inline int inlineUTF8SequenceLengthNonASCII(char b0)
{
if ((b0 & 0xC0) != 0xC0)
return 0;
if ((b0 & 0xE0) == 0xC0)
return 2;
if ((b0 & 0xF0) == 0xE0)
return 3;
if ((b0 & 0xF8) == 0xF0)
return 4;
return 0;
}
inline int inlineUTF8SequenceLength(char b0)
{
return (b0 & 0x80) == 0 ? 1 : inlineUTF8SequenceLengthNonASCII(b0);
}
int UTF8SequenceLength(char b0)
{
return (b0 & 0x80) == 0 ? 1 : inlineUTF8SequenceLengthNonASCII(b0);
}
int decodeUTF8Sequence(const char* sequence)
{
const unsigned char b0 = sequence[0];
const int length = inlineUTF8SequenceLength(b0);
if (length == 0)
return -1;
const unsigned char b1 = sequence[1];
if (length == 1) {
if (b1)
return -1;
return b0;
}
if ((b1 & 0xC0) != 0x80)
return -1;
const unsigned char b2 = sequence[2];
if (length == 2) {
if (b2)
return -1;
const int c = ((b0 & 0x1F) << 6) | (b1 & 0x3F);
if (c < 0x80)
return -1;
return c;
}
if ((b2 & 0xC0) != 0x80)
return -1;
const unsigned char b3 = sequence[3];
if (length == 3) {
if (b3)
return -1;
const int c = ((b0 & 0xF) << 12) | ((b1 & 0x3F) << 6) | (b2 & 0x3F);
if (c < 0x800)
return -1;
if (c >= 0xD800 && c <= 0xDFFF)
return -1;
return c;
}
if ((b3 & 0xC0) != 0x80)
return -1;
const unsigned char b4 = sequence[4];
if (length == 4) {
if (b4)
return -1;
const int c = ((b0 & 0x7) << 18) | ((b1 & 0x3F) << 12) | ((b2 & 0x3F) << 6) | (b3 & 0x3F);
if (c < 0x10000 || c > 0x10FFFF)
return -1;
return c;
}
return -1;
}
static const unsigned char firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
ConversionResult convertUTF16ToUTF8(
const UChar** sourceStart, const UChar* sourceEnd,
char** targetStart, char* targetEnd, bool strict)
{
ConversionResult result = conversionOK;
const UChar* source = *sourceStart;
char* target = *targetStart;
while (source < sourceEnd) {
UChar32 ch;
unsigned short bytesToWrite = 0;
const UChar32 byteMask = 0xBF;
const UChar32 byteMark = 0x80;
const UChar* oldSource = source; ch = static_cast<unsigned short>(*source++);
if (ch >= 0xD800 && ch <= 0xDBFF) {
if (source < sourceEnd) {
UChar32 ch2 = static_cast<unsigned short>(*source);
if (ch2 >= 0xDC00 && ch2 <= 0xDFFF) {
ch = ((ch - 0xD800) << 10) + (ch2 - 0xDC00) + 0x0010000;
++source;
} else if (strict) { --source; result = sourceIllegal;
break;
}
} else { --source; result = sourceExhausted;
break;
}
} else if (strict) {
if (ch >= 0xDC00 && ch <= 0xDFFF) {
--source; result = sourceIllegal;
break;
}
}
if (ch < (UChar32)0x80) {
bytesToWrite = 1;
} else if (ch < (UChar32)0x800) {
bytesToWrite = 2;
} else if (ch < (UChar32)0x10000) {
bytesToWrite = 3;
} else if (ch < (UChar32)0x110000) {
bytesToWrite = 4;
} else {
bytesToWrite = 3;
ch = 0xFFFD;
}
target += bytesToWrite;
if (target > targetEnd) {
source = oldSource; target -= bytesToWrite;
result = targetExhausted;
break;
}
switch (bytesToWrite) { case 4: *--target = (char)((ch | byteMark) & byteMask); ch >>= 6;
case 3: *--target = (char)((ch | byteMark) & byteMask); ch >>= 6;
case 2: *--target = (char)((ch | byteMark) & byteMask); ch >>= 6;
case 1: *--target = (char)(ch | firstByteMark[bytesToWrite]);
}
target += bytesToWrite;
}
*sourceStart = source;
*targetStart = target;
return result;
}
static bool isLegalUTF8(const unsigned char* source, int length)
{
unsigned char a;
const unsigned char* srcptr = source + length;
switch (length) {
default: return false;
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) {
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;
}
static const UChar32 offsetsFromUTF8[6] = { 0x00000000UL, 0x00003080UL, 0x000E2080UL,
0x03C82080UL, 0xFA082080UL, 0x82082080UL };
ConversionResult convertUTF8ToUTF16(
const char** sourceStart, const char* sourceEnd,
UChar** targetStart, UChar* targetEnd, bool strict)
{
ConversionResult result = conversionOK;
const char* source = *sourceStart;
UChar* target = *targetStart;
while (source < sourceEnd) {
UChar32 ch = 0;
int extraBytesToRead = UTF8SequenceLength(*source) - 1;
if (source + extraBytesToRead >= sourceEnd) {
result = sourceExhausted;
break;
}
if (!isLegalUTF8(reinterpret_cast<const unsigned char*>(source), extraBytesToRead + 1)) {
result = sourceIllegal;
break;
}
switch (extraBytesToRead) {
case 5: ch += static_cast<unsigned char>(*source++); ch <<= 6; case 4: ch += static_cast<unsigned char>(*source++); ch <<= 6; case 3: ch += static_cast<unsigned char>(*source++); ch <<= 6;
case 2: ch += static_cast<unsigned char>(*source++); ch <<= 6;
case 1: ch += static_cast<unsigned char>(*source++); ch <<= 6;
case 0: ch += static_cast<unsigned char>(*source++);
}
ch -= offsetsFromUTF8[extraBytesToRead];
if (target >= targetEnd) {
source -= (extraBytesToRead + 1); result = targetExhausted; break;
}
if (ch <= 0xFFFF) {
if (ch >= 0xD800 && ch <= 0xDFFF) {
if (strict) {
source -= (extraBytesToRead + 1); result = sourceIllegal;
break;
} else
*target++ = 0xFFFD;
} else
*target++ = (UChar)ch; } else if (ch > 0x10FFFF) {
if (strict) {
result = sourceIllegal;
source -= (extraBytesToRead + 1); break; } else
*target++ = 0xFFFD;
} else {
if (target + 1 >= targetEnd) {
source -= (extraBytesToRead + 1); result = targetExhausted;
break;
}
ch -= 0x0010000UL;
*target++ = (UChar)((ch >> 10) + 0xD800);
*target++ = (UChar)((ch & 0x03FF) + 0xDC00);
}
}
*sourceStart = source;
*targetStart = target;
return result;
}
}
}