Bug 757366 - Don't cast pointers to 'name'-table data to uint16_t*, as they may not be 16-bit-aligned. r=jrmuizel

This commit is contained in:
Jonathan Kew 2016-09-26 18:05:14 +01:00
Родитель 60fef630a5
Коммит 2a3be4b384
1 изменённых файлов: 14 добавлений и 12 удалений

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@ -918,16 +918,18 @@ IsValidSFNTVersion(uint32_t version)
version == TRUETYPE_TAG('t','r','u','e');
}
// copy and swap UTF-16 values, assume no surrogate pairs, can be in place
// Copy and swap UTF-16 values, assume no surrogate pairs, can be in place.
// aInBuf and aOutBuf are NOT necessarily 16-bit-aligned, so we should avoid
// accessing them directly as uint16_t* values.
// aLen is count of UTF-16 values, so the byte buffers are twice that.
static void
CopySwapUTF16(const uint16_t *aInBuf, uint16_t *aOutBuf, uint32_t aLen)
CopySwapUTF16(const char* aInBuf, char* aOutBuf, uint32_t aLen)
{
const uint16_t *end = aInBuf + aLen;
const char* end = aInBuf + aLen * 2;
while (aInBuf < end) {
uint16_t value = *aInBuf;
*aOutBuf = (value >> 8) | (value & 0xff) << 8;
aOutBuf++;
aInBuf++;
uint8_t b0 = *aInBuf++;
*aOutBuf++ = *aInBuf++;
*aOutBuf++ = b0;
}
}
@ -1446,13 +1448,13 @@ gfxFontUtils::DecodeFontName(const char *aNameData, int32_t aByteLen,
if (csName[0] == 0) {
// empty charset name: data is utf16be, no need to instantiate a converter
uint32_t strLen = aByteLen / 2;
#ifdef IS_LITTLE_ENDIAN
aName.SetLength(strLen);
CopySwapUTF16(reinterpret_cast<const uint16_t*>(aNameData),
reinterpret_cast<uint16_t*>(aName.BeginWriting()), strLen);
#ifdef IS_LITTLE_ENDIAN
CopySwapUTF16(aNameData, reinterpret_cast<char*>(aName.BeginWriting()),
strLen);
#else
aName.Assign(reinterpret_cast<const char16_t*>(aNameData), strLen);
#endif
memcpy(aName.BeginWriting(), aNameData, strLen * 2);
#endif
return true;
}