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COMMON: PKWARE data comp. lib. mask dictionary xs

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added masking of dictionary offsets when copying from dictionary
issues should now all be fixed
This commit is contained in:
Martin Kiewitz 2015-07-04 03:10:26 +02:00
parent 4fb32647ad
commit 614162e5fc
1 changed files with 19 additions and 35 deletions
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54
common/dcl.cpp
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@ -338,6 +338,7 @@ bool DecompressorDCL::unpack(SeekableReadStream *sourceStream, WriteStream *targ
byte dictionary[MIDI_SETUP_BUNDLE_FILE_MAXIMUM_DICTIONARY_SIZE];
uint16 dictionaryPos = 0;
uint16 dictionarySize = 0;
uint16 dictionaryMask = 0;
int value;
uint16 tokenOffset = 0;
uint16 tokenLength = 0;
@ -369,6 +370,7 @@ bool DecompressorDCL::unpack(SeekableReadStream *sourceStream, WriteStream *targ
warning("DCL-INFLATE: Error: unsupported dictionary type %02x", dictionaryType);
return false;
}
dictionaryMask = dictionarySize - 1;
while ((!targetFixedSize) || (_bytesWritten < _targetSize)) {
if (getBitsLSB(1)) { // (length,distance) pair
@ -408,47 +410,29 @@ bool DecompressorDCL::unpack(SeekableReadStream *sourceStream, WriteStream *targ
return false;
}
if (!targetPtr) {
// FIXME: there is some issue in this code that causes some graphics glitches in SCI
// will figure this out tomorrow. For now the old code is called for those cases and
// that makes it work.
uint16 dictionaryBaseIndex = (dictionaryPos - tokenOffset) & (dictionarySize - 1);
uint16 dictionaryIndex = dictionaryBaseIndex;
uint16 dictionaryNextIndex = dictionaryPos;
uint16 dictionaryBaseIndex = (dictionaryPos - tokenOffset) & dictionaryMask;
uint16 dictionaryIndex = dictionaryBaseIndex;
uint16 dictionaryNextIndex = dictionaryPos;
while (tokenLength) {
// Write byte from dictionary
putByte(dictionary[dictionaryIndex]);
debug(9, "\33[32;31m%02x\33[37;37m ", dictionary[dictionaryIndex]);
while (tokenLength) {
// Write byte from dictionary
putByte(dictionary[dictionaryIndex]);
debug(9, "\33[32;31m%02x\33[37;37m ", dictionary[dictionaryIndex]);
dictionary[dictionaryNextIndex] = dictionary[dictionaryIndex];
dictionaryNextIndex++; dictionaryIndex++;
dictionary[dictionaryNextIndex] = dictionary[dictionaryIndex];
if (dictionaryIndex == dictionaryPos)
dictionaryIndex = dictionaryBaseIndex;
if (dictionaryNextIndex == dictionarySize)
dictionaryNextIndex = 0;
dictionaryNextIndex = (dictionaryNextIndex + 1) & dictionaryMask;
dictionaryIndex = (dictionaryIndex + 1) & dictionaryMask;
tokenLength--;
}
dictionaryPos = dictionaryNextIndex;
debug(9, "\n");
} else {
while (tokenLength) {
uint32 copy_length = (tokenLength > tokenOffset) ? tokenOffset : tokenLength;
assert(tokenLength >= copy_length);
uint32 pos = _bytesWritten - tokenOffset;
for (uint32 i = 0; i < copy_length; i++)
putByte(targetPtr[pos + i]);
if (dictionaryIndex == dictionaryPos)
dictionaryIndex = dictionaryBaseIndex;
if (dictionaryNextIndex == dictionarySize)
dictionaryNextIndex = 0;
for (uint32 i = 0; i < copy_length; i++)
debug(9, "\33[32;31m%02x\33[37;37m ", targetPtr[pos + i]);
debug(9, "\n");
tokenLength -= copy_length;
tokenOffset += copy_length;
}
tokenLength--;
}
dictionaryPos = dictionaryNextIndex;
debug(9, "\n");
} else { // Copy byte verbatim
value = (mode == DCL_ASCII_MODE) ? huffman_lookup(ascii_tree) : getByteLSB();