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[lcrash/cckernel] FIX: Add support for fixed huffman compression

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xwashere 2024-04-17 13:15:34 -04:00
parent d81dd11837
commit fc7520c16f
Signed by: XWasHere
GPG Key ID: 042F8BFA1B0EF93B
1 changed files with 46 additions and 41 deletions
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21
lcrash/setup/compressed/gzip.c
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@ -150,16 +150,21 @@ uptr GzipDecompress(c8* Input, uptr InputSize, c8* Output) {
case 0: { // NO COMPRESSION
break;
}
case 1: {
// FIXED HUFFMAN
break;
}
case 1: // FIXED HUFFMAN
case 2: { // DYNAMIC HUFFMAN
// Get huffman code counts
u64 OperationCount = GzipFetchBits(Stream, &BitLocation, 5) + 257;
u64 DistanceCount = GzipFetchBits(Stream, &BitLocation, 5) + 1;
u64 CodeCount = GzipFetchBits(Stream, &BitLocation, 4) + 4;
u64 OperationCount = (head & 2) ? 288 : GzipFetchBits(Stream, &BitLocation, 5) + 257;
u64 DistanceCount = (head & 2) ? 31 : GzipFetchBits(Stream, &BitLocation, 5) + 1;
u64 CodeCount = (head & 2) ? 0 : GzipFetchBits(Stream, &BitLocation, 4) + 4;
u8 Lengths[OperationCount + DistanceCount] = {};
if (head & 2) { // Build fixed huffman lengths
for (int i = 0; i <= 143; i++) Lengths[i] = 8;
for (int i = 143; i <= 255; i++) Lengths[i] = 9;
for (int i = 256; i <= 279; i++) Lengths[i] = 7;
for (int i = 280; i <= 287; i++) Lengths[i] = 8;
for (int i = 288; i <= 319; i++) Lengths[i] = 5;
} else { // Build dynamic huffman lengths
const u8 CodeLengthLengthOffset[19] = { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 };
u8 CodeLengthLengthProto[19] = {};
for (int i = 0; i < CodeCount; i++) {
@ -172,7 +177,6 @@ uptr GzipDecompress(c8* Input, uptr InputSize, c8* Output) {
GzipPopulateTable(CodeLengthLengthProto, 19, CodeLengthLengths, CodeLengthSymbols, 0x80, 7);
// Collect lengths
u8 Lengths[OperationCount + DistanceCount] = {};
uptr CurrentLen = 0;
while (CurrentLen < OperationCount + DistanceCount) {
// Fetch the next op
@ -201,6 +205,7 @@ uptr GzipDecompress(c8* Input, uptr InputSize, c8* Output) {
}
}
}
}
// Build operation table
u32 OperationMaxBits = 0;