void
GIFLoad::ResetTable()
{
fBits = fCodeSize + 1;
fNextCode = fClearCode + 2;
fMaxCode = (1 << fBits) - 1;
MemblockDeleteAll();
for (int x = 0; x < 4096; x++) {
fTable[x] = NULL;
if (x < (1 << fCodeSize)) {
fTable[x] = MemblockAllocate(1);
fTable[x][0] = x;
fEntrySize[x] = 1;
}
}
}
bool
GIFLoad::ReadGIFImageData()
{
unsigned char newEntry[ENTRY_COUNT];
unsigned char codeSize;
if (fInput->Read(&codeSize, 1) < 1)
return false;
if (codeSize > fPalette->size_in_bits) {
if (debug) {
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - "
"Code_size should be %d, not %d, allowing it\n",
fCodeSize, codeSize);
}
if (!InitFrame(codeSize))
return false;
} else if (codeSize < fPalette->size_in_bits) {
if (debug) {
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - "
"Code_size should be %d, not %d\n", fCodeSize, codeSize);
}
return false;
} else if (!InitFrame(fPalette->size_in_bits))
return false;
if (debug)
syslog(LOG_INFO, "GIFLoad::ReadGIFImageData() - Starting LZW\n");
while ((fNewCode = NextCode()) != -1 && fNewCode != fEndCode) {
if (fNewCode == fClearCode) {
ResetTable();
fNewCode = NextCode();
fOldCode[0] = fNewCode;
fOldCodeLength = 1;
if (!OutputColor(fOldCode, 1))
goto bad_end;
if (fNewCode == -1 || fNewCode == fEndCode) {
if (debug) {
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - "
"Premature fEndCode or error reading fNewCode\n");
}
goto bad_end;
}
continue;
}
// explicitly check for lack of clear code at start of file
if (fOldCodeLength == 0) {
fOldCode[0] = fNewCode;
fOldCodeLength = 1;
if (!OutputColor(fOldCode, 1))
goto bad_end;
continue;
}
// error out if we're trying to access an out-of-bounds index
if (fNextCode >= ENTRY_COUNT)
goto bad_end;
if (fTable[fNewCode] != NULL) {
// exists in table
if (!OutputColor(fTable[fNewCode], fEntrySize[fNewCode]))
goto bad_end;
//memcpy(newEntry, fOldCode, fOldCodeLength);
for (unsigned int x = 0; x < fOldCodeLength; x++)
newEntry[x] = fOldCode[x];
//memcpy(newEntry + fOldCodeLength, fTable[fNewCode], 1);
newEntry[fOldCodeLength] = fTable[fNewCode][0];
} else {
// does not exist in table
//memcpy(newEntry, fOldCode, fOldCodeLength);
for (unsigned int x = 0; x < fOldCodeLength; x++)
newEntry[x] = fOldCode[x];
//memcpy(newEntry + fOldCodeLength, fOldCode, 1);
newEntry[fOldCodeLength] = fOldCode[0];
if (!OutputColor(newEntry, fOldCodeLength + 1))
goto bad_end;
}
fTable[fNextCode] = MemblockAllocate(fOldCodeLength + 1);
if (fTable[fNextCode] == NULL)
goto bad_end;
//memcpy(fTable[fNextCode], newEntry, fOldCodeLength + 1);
for (unsigned int x = 0; x < fOldCodeLength + 1; x++)
fTable[fNextCode][x] = newEntry[x];
fEntrySize[fNextCode] = fOldCodeLength + 1;
//memcpy(fOldCode, fTable[fNewCode], fEntrySize[fNewCode]);
for (int x = 0; x < fEntrySize[fNewCode]; x++)
fOldCode[x] = fTable[fNewCode][x];
fOldCodeLength = fEntrySize[fNewCode];
fNextCode++;
if (fNextCode > fMaxCode && fBits < LZ_MAX_BITS) {
fBits++;
fMaxCode = (1 << fBits) - 1;
}
}
MemblockDeleteAll();
if (fNewCode == -1)
return false;
if (debug)
syslog(LOG_INFO, "GIFLoad::ReadGIFImageData() - Done\n");
return true;
bad_end:
if (debug)
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - Reached a bad end\n");
MemblockDeleteAll();
return false;
}
bool
GIFLoad::ReadGIFImageData()
{
unsigned char newEntry[4096];
unsigned char cs;
fInput->Read(&cs, 1);
if (cs == fPalette->size_in_bits) {
if (!InitFrame(fPalette->size_in_bits))
return false;
} else if (cs > fPalette->size_in_bits) {
if (debug)
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - Code_size should be %d, not "
"%d, allowing it\n", fCodeSize, cs);
if (!InitFrame(cs))
return false;
} else if (cs < fPalette->size_in_bits) {
if (debug)
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - Code_size should be %d, not "
"%d\n", fCodeSize, cs);
return false;
}
if (debug)
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - Starting LZW\n");
while ((fNewCode = NextCode()) != -1 && fNewCode != fEndCode) {
if (fNewCode == fClearCode) {
ResetTable();
fNewCode = NextCode();
fOldCode[0] = fNewCode;
fOldCodeLength = 1;
if (!OutputColor(fOldCode, 1)) goto bad_end;
if (fNewCode == -1 || fNewCode == fEndCode) {
if (debug)
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - Premature fEndCode "
"or error\n");
goto bad_end;
}
continue;
}
// Explicitly check for lack of clear code at start of file
if (fOldCodeLength == 0) {
fOldCode[0] = fNewCode;
fOldCodeLength = 1;
if (!OutputColor(fOldCode, 1))
goto bad_end;
continue;
}
if (fTable[fNewCode] != NULL) { // Does exist in table
if (!OutputColor(fTable[fNewCode], fEntrySize[fNewCode]))
goto bad_end;
//memcpy(newEntry, fOldCode, fOldCodeLength);
for (int x = 0; x < fOldCodeLength; x++) {
newEntry[x] = fOldCode[x];
}
//memcpy(newEntry + fOldCodeLength, fTable[fNewCode], 1);
newEntry[fOldCodeLength] = *fTable[fNewCode];
} else { // Does not exist in table
//memcpy(newEntry, fOldCode, fOldCodeLength);
for (int x = 0; x < fOldCodeLength; x++) {
newEntry[x] = fOldCode[x];
}
//memcpy(newEntry + fOldCodeLength, fOldCode, 1);
newEntry[fOldCodeLength] = *fOldCode;
if (!OutputColor(newEntry, fOldCodeLength + 1))
goto bad_end;
}
fTable[fNextCode] = MemblockAllocate(fOldCodeLength + 1);
//memcpy(fTable[fNextCode], newEntry, fOldCodeLength + 1);
for (int x = 0; x < fOldCodeLength + 1; x++) {
fTable[fNextCode][x] = newEntry[x];
}
fEntrySize[fNextCode] = fOldCodeLength + 1;
//memcpy(fOldCode, fTable[fNewCode], fEntrySize[fNewCode]);
for (int x = 0; x < fEntrySize[fNewCode]; x++) {
fOldCode[x] = fTable[fNewCode][x];
}
fOldCodeLength = fEntrySize[fNewCode];
fNextCode++;
if (fNextCode > fMaxCode && fBits != 12) {
fBits++;
fMaxCode = (1 << fBits) - 1;
}
}
MemblockDeleteAll();
if (fNewCode == -1)
return false;
if (debug)
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - Done\n");
return true;
bad_end:
if (debug)
syslog(LOG_ERR, "GIFLoad::ReadGIFImageData() - Reached a bad end\n");
MemblockDeleteAll();
return false;
}
