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It takes about 5.2 seconds to load and decompress the entire 115mb database on my quad-core i5-6600k. Needless to say, there will be some cutting this down via tossing out some number of puzzles.master
6 changed files with 774 additions and 13 deletions
@ -0,0 +1,69 @@ |
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(comptime-define-symbol 'Unix) |
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(set-cakelisp-option cakelisp-src-dir "Dependencies/cakelisp/src") |
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(add-cakelisp-search-directory "test/src" "Dependencies/cakelisp/runtime") |
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(import &comptime-only "Macros.cake") |
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|
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(add-c-search-directory-module "../../src") ;; Building from Dependencies/gamelib |
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(c-import "<stdio.h>" "<stdlib.h>" "<fcntl.h>" "<unistd.h>" |
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"bunzip.h") |
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|
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(add-c-build-dependency "bunzip-4.1.c") ;; LGPLv2 |
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|
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(var-global g-bunzip-debug bool false) |
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|
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(defun bunzip-decompress (bz2-file (* (const char)) &return bool) |
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(var file-descriptor int (open bz2-file O_RDONLY)) |
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(when (= -1 file-descriptor) |
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(printf "Failed to load file %s\n" bz2-file) |
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(return false)) |
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|
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;; Prints all of it, which is a lot! |
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;; (unless (= 0 (uncompressStream file-descriptor 1)) |
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;; (return false)) |
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|
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(var header-data (* bunzip_data) null) |
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(var error-code int 0) |
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(set error-code (start_bunzip (addr header-data) file-descriptor |
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null 0)) ;; Unused: Input buffer |
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(when error-code |
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(printf "Bunzip error %d\n" error-code) |
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(free header-data) |
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(close file-descriptor) |
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(return false)) |
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|
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;; Add room for null terminator. Not necessary for binary data |
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(var output ([] 4097 char) (array 0)) |
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(var num-bytes-read int 0) |
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(while true |
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(var return-code int (read_bunzip header-data output (- (array-size output) 1))) |
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(when (< return-code RETVAL_LAST_BLOCK) ;; On success, return code = num bytes written |
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(printf "Bunzip error %d\n" return-code) |
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(free header-data) |
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(close file-descriptor) |
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(return false)) |
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|
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(when (> return-code 0) |
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;; Set null terminator |
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(set (at return-code output) 0) |
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(set num-bytes-read (+ num-bytes-read return-code))) |
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|
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;; (printf "Output: %d bytes\n%s[end]\n" return-code output) |
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(when (= return-code RETVAL_LAST_BLOCK) |
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(when g-bunzip-debug (printf "Last Output: %s[end]\n" output)) |
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(break))) |
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|
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(when g-bunzip-debug (printf "Output: %d bytes\n" num-bytes-read)) |
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(free header-data) |
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(close file-descriptor) |
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(return true)) |
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|
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(comptime-cond |
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('Kitty-Main) |
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(true ;; Standalone test |
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(defun main (&return int) |
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(var bz2-file (* (const char)) "assets/rush.txt.bz2") |
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(unless (bunzip-decompress bz2-file) |
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(return 1)) |
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(return 0)) |
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|
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(set-cakelisp-option executable-output "../../decompression-test"))) |
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@ -0,0 +1,543 @@ |
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/* vi: set sw=4 ts=4: */ |
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/* Small bzip2 deflate implementation, by Rob Landley (rob@landley.net).
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Based on bzip2 decompression code by Julian R Seward (jseward@acm.org), |
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which also acknowledges contributions by Mike Burrows, David Wheeler, |
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Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten, |
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Robert Sedgewick, and Jon L. Bentley. |
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|
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This code is licensed under the LGPLv2: |
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LGPL (http://www.gnu.org/copyleft/lgpl.html
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*/ |
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|
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/*
|
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Size and speed optimizations by Manuel Novoa III (mjn3@codepoet.org). |
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|
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More efficient reading of huffman codes, a streamlined read_bunzip() |
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function, and various other tweaks. In (limited) tests, approximately |
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20% faster than bzcat on x86 and about 10% faster on arm. |
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|
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Note that about 2/3 of the time is spent in read_unzip() reversing |
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the Burrows-Wheeler transformation. Much of that time is delay |
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resulting from cache misses. |
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|
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I would ask that anyone benefiting from this work, especially those |
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using it in commercial products, consider making a donation to my local |
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non-profit hospice organization (see www.hospiceacadiana.com) in the |
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name of the woman I loved, Toni W. Hagan, who passed away Feb. 12, 2003. |
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Manuel |
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*/ |
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|
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/* Modified by Macoy Madson:
|
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- Give no errors with a C++ compiler (all -fpermissive errors) |
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- Add header file |
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*/ |
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#include "bunzip.h" |
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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include <unistd.h> |
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#include <limits.h> |
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|
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/* Return the next nnn bits of input. All reads from the compressed input
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are done through this function. All reads are big endian */ |
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static unsigned int get_bits(bunzip_data *bd, char bits_wanted) |
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{ |
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unsigned int bits=0; |
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|
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/* If we need to get more data from the byte buffer, do so. (Loop getting
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one byte at a time to enforce endianness and avoid unaligned access.) */ |
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while (bd->inbufBitCount<bits_wanted) { |
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/* If we need to read more data from file into byte buffer, do so */ |
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if(bd->inbufPos==bd->inbufCount) { |
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if((bd->inbufCount = read(bd->in_fd, bd->inbuf, IOBUF_SIZE)) <= 0) |
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longjmp(bd->jmpbuf,RETVAL_UNEXPECTED_INPUT_EOF); |
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bd->inbufPos=0; |
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} |
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/* Avoid 32-bit overflow (dump bit buffer to top of output) */ |
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if(bd->inbufBitCount>=24) { |
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bits=bd->inbufBits&((1<<bd->inbufBitCount)-1); |
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bits_wanted-=bd->inbufBitCount; |
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bits<<=bits_wanted; |
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bd->inbufBitCount=0; |
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} |
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/* Grab next 8 bits of input from buffer. */ |
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bd->inbufBits=(bd->inbufBits<<8)|bd->inbuf[bd->inbufPos++]; |
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bd->inbufBitCount+=8; |
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} |
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/* Calculate result */ |
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bd->inbufBitCount-=bits_wanted; |
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bits|=(bd->inbufBits>>bd->inbufBitCount)&((1<<bits_wanted)-1); |
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return bits; |
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} |
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|
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/* Unpacks the next block and sets up for the inverse burrows-wheeler step. */ |
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static int get_next_block(bunzip_data *bd) |
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{ |
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struct group_data *hufGroup; |
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int dbufCount,nextSym,dbufSize,groupCount,*base,*limit,selector, |
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i,j,k,t,runPos,symCount,symTotal,nSelectors,byteCount[256]; |
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unsigned char uc, symToByte[256], mtfSymbol[256], *selectors; |
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unsigned int *dbuf,origPtr; |
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dbuf=bd->dbuf; |
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dbufSize=bd->dbufSize; |
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selectors=bd->selectors; |
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/* Reset longjmp I/O error handling */ |
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i=setjmp(bd->jmpbuf); |
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if(i) return i; |
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/* Read in header signature and CRC, then validate signature.
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(last block signature means CRC is for whole file, return now) */ |
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i = get_bits(bd,24); |
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j = get_bits(bd,24); |
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bd->headerCRC=get_bits(bd,32); |
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if ((i == 0x177245) && (j == 0x385090)) return RETVAL_LAST_BLOCK; |
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if ((i != 0x314159) || (j != 0x265359)) return RETVAL_NOT_BZIP_DATA; |
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/* We can add support for blockRandomised if anybody complains. There was
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some code for this in busybox 1.0.0-pre3, but nobody ever noticed that |
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it didn't actually work. */ |
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if(get_bits(bd,1)) return RETVAL_OBSOLETE_INPUT; |
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if((origPtr=get_bits(bd,24)) > dbufSize) return RETVAL_DATA_ERROR; |
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/* mapping table: if some byte values are never used (encoding things
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like ascii text), the compression code removes the gaps to have fewer |
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symbols to deal with, and writes a sparse bitfield indicating which |
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values were present. We make a translation table to convert the symbols |
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back to the corresponding bytes. */ |
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t=get_bits(bd, 16); |
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symTotal=0; |
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for (i=0;i<16;i++) { |
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if(t&(1<<(15-i))) { |
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k=get_bits(bd,16); |
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for(j=0;j<16;j++) |
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if(k&(1<<(15-j))) symToByte[symTotal++]=(16*i)+j; |
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} |
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} |
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/* How many different huffman coding groups does this block use? */ |
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groupCount=get_bits(bd,3); |
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if (groupCount<2 || groupCount>MAX_GROUPS) return RETVAL_DATA_ERROR; |
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/* nSelectors: Every GROUP_SIZE many symbols we select a new huffman coding
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group. Read in the group selector list, which is stored as MTF encoded |
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bit runs. (MTF=Move To Front, as each value is used it's moved to the |
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start of the list.) */ |
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if(!(nSelectors=get_bits(bd, 15))) return RETVAL_DATA_ERROR; |
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for(i=0; i<groupCount; i++) mtfSymbol[i] = i; |
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for(i=0; i<nSelectors; i++) { |
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/* Get next value */ |
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for(j=0;get_bits(bd,1);j++) if (j>=groupCount) return RETVAL_DATA_ERROR; |
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/* Decode MTF to get the next selector */ |
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uc = mtfSymbol[j]; |
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for(;j;j--) mtfSymbol[j] = mtfSymbol[j-1]; |
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mtfSymbol[0]=selectors[i]=uc; |
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} |
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/* Read the huffman coding tables for each group, which code for symTotal
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literal symbols, plus two run symbols (RUNA, RUNB) */ |
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symCount=symTotal+2; |
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for (j=0; j<groupCount; j++) { |
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unsigned char length[MAX_SYMBOLS],temp[MAX_HUFCODE_BITS+1]; |
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int minLen, maxLen, pp; |
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/* Read huffman code lengths for each symbol. They're stored in
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a way similar to mtf; record a starting value for the first symbol, |
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and an offset from the previous value for everys symbol after that. |
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(Subtracting 1 before the loop and then adding it back at the end is |
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an optimization that makes the test inside the loop simpler: symbol |
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length 0 becomes negative, so an unsigned inequality catches it.) */ |
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t=get_bits(bd, 5)-1; |
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for (i = 0; i < symCount; i++) { |
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for(;;) { |
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if (((unsigned)t) > (MAX_HUFCODE_BITS-1)) |
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return RETVAL_DATA_ERROR; |
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/* If first bit is 0, stop. Else second bit indicates whether
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to increment or decrement the value. Optimization: grab 2 |
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bits and unget the second if the first was 0. */ |
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k = get_bits(bd,2); |
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if (k < 2) { |
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bd->inbufBitCount++; |
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break; |
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} |
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/* Add one if second bit 1, else subtract 1. Avoids if/else */ |
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t+=(((k+1)&2)-1); |
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} |
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/* Correct for the initial -1, to get the final symbol length */ |
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length[i]=t+1; |
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} |
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/* Find largest and smallest lengths in this group */ |
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minLen=maxLen=length[0]; |
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for(i = 1; i < symCount; i++) { |
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if(length[i] > maxLen) maxLen = length[i]; |
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else if(length[i] < minLen) minLen = length[i]; |
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} |
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/* Calculate permute[], base[], and limit[] tables from length[].
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* |
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* permute[] is the lookup table for converting huffman coded symbols |
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* into decoded symbols. base[] is the amount to subtract from the |
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* value of a huffman symbol of a given length when using permute[]. |
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* |
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* limit[] indicates the largest numerical value a symbol with a given |
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* number of bits can have. This is how the huffman codes can vary in |
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* length: each code with a value>limit[length] needs another bit. |
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*/ |
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hufGroup=bd->groups+j; |
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hufGroup->minLen = minLen; |
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hufGroup->maxLen = maxLen; |
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/* Note that minLen can't be smaller than 1, so we adjust the base
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and limit array pointers so we're not always wasting the first |
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entry. We do this again when using them (during symbol decoding).*/ |
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base=hufGroup->base-1; |
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limit=hufGroup->limit-1; |
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/* Calculate permute[]. Concurently, initialize temp[] and limit[]. */ |
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pp=0; |
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for(i=minLen;i<=maxLen;i++) { |
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temp[i]=limit[i]=0; |
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for(t=0;t<symCount;t++) |
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if(length[t]==i) hufGroup->permute[pp++] = t; |
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} |
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/* Count symbols coded for at each bit length */ |
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for (i=0;i<symCount;i++) temp[length[i]]++; |
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/* Calculate limit[] (the largest symbol-coding value at each bit
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* length, which is (previous limit<<1)+symbols at this level), and |
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* base[] (number of symbols to ignore at each bit length, which is |
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* limit minus the cumulative count of symbols coded for already). */ |
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pp=t=0; |
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for (i=minLen; i<maxLen; i++) { |
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pp+=temp[i]; |
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/* We read the largest possible symbol size and then unget bits
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after determining how many we need, and those extra bits could |
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be set to anything. (They're noise from future symbols.) At |
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each level we're really only interested in the first few bits, |
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so here we set all the trailing to-be-ignored bits to 1 so they |
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don't affect the value>limit[length] comparison. */ |
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limit[i]= (pp << (maxLen - i)) - 1; |
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pp<<=1; |
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base[i+1]=pp-(t+=temp[i]); |
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} |
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limit[maxLen+1] = INT_MAX; /* Sentinal value for reading next sym. */ |
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limit[maxLen]=pp+temp[maxLen]-1; |
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base[minLen]=0; |
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} |
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/* We've finished reading and digesting the block header. Now read this
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block's huffman coded symbols from the file and undo the huffman coding |
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and run length encoding, saving the result into dbuf[dbufCount++]=uc */ |
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|
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/* Initialize symbol occurrence counters and symbol Move To Front table */ |
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for(i=0;i<256;i++) { |
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byteCount[i] = 0; |
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mtfSymbol[i]=(unsigned char)i; |
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} |
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/* Loop through compressed symbols. */ |
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runPos=dbufCount=symCount=selector=0; |
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for(;;) { |
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/* Determine which huffman coding group to use. */ |
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if(!(symCount--)) { |
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symCount=GROUP_SIZE-1; |
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if(selector>=nSelectors) return RETVAL_DATA_ERROR; |
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hufGroup=bd->groups+selectors[selector++]; |
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base=hufGroup->base-1; |
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limit=hufGroup->limit-1; |
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} |
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/* Read next huffman-coded symbol. */ |
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/* Note: It is far cheaper to read maxLen bits and back up than it is
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to read minLen bits and then an additional bit at a time, testing |
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as we go. Because there is a trailing last block (with file CRC), |
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there is no danger of the overread causing an unexpected EOF for a |
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valid compressed file. As a further optimization, we do the read |
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inline (falling back to a call to get_bits if the buffer runs |
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dry). The following (up to got_huff_bits:) is equivalent to |
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j=get_bits(bd,hufGroup->maxLen); |
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*/ |
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while (bd->inbufBitCount<hufGroup->maxLen) { |
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if(bd->inbufPos==bd->inbufCount) { |
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j = get_bits(bd,hufGroup->maxLen); |
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goto got_huff_bits; |
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} |
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bd->inbufBits=(bd->inbufBits<<8)|bd->inbuf[bd->inbufPos++]; |
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bd->inbufBitCount+=8; |
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}; |
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bd->inbufBitCount-=hufGroup->maxLen; |
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j = (bd->inbufBits>>bd->inbufBitCount)&((1<<hufGroup->maxLen)-1); |
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got_huff_bits: |
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/* Figure how how many bits are in next symbol and unget extras */ |
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i=hufGroup->minLen; |
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while(j>limit[i]) ++i; |
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bd->inbufBitCount += (hufGroup->maxLen - i); |
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/* Huffman decode value to get nextSym (with bounds checking) */ |
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if ((i > hufGroup->maxLen) |
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|| (((unsigned)(j=(j>>(hufGroup->maxLen-i))-base[i])) |
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>= MAX_SYMBOLS)) |
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return RETVAL_DATA_ERROR; |
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nextSym = hufGroup->permute[j]; |
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/* We have now decoded the symbol, which indicates either a new literal
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byte, or a repeated run of the most recent literal byte. First, |
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check if nextSym indicates a repeated run, and if so loop collecting |
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how many times to repeat the last literal. */ |
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if (((unsigned)nextSym) <= SYMBOL_RUNB) { /* RUNA or RUNB */ |
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/* If this is the start of a new run, zero out counter */ |
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if(!runPos) { |
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runPos = 1; |
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t = 0; |
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} |
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/* Neat trick that saves 1 symbol: instead of or-ing 0 or 1 at
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each bit position, add 1 or 2 instead. For example, |
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1011 is 1<<0 + 1<<1 + 2<<2. 1010 is 2<<0 + 2<<1 + 1<<2. |
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You can make any bit pattern that way using 1 less symbol than |
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the basic or 0/1 method (except all bits 0, which would use no |
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symbols, but a run of length 0 doesn't mean anything in this |
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context). Thus space is saved. */ |
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t += (runPos << nextSym); /* +runPos if RUNA; +2*runPos if RUNB */ |
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runPos <<= 1; |
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continue; |
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} |
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/* When we hit the first non-run symbol after a run, we now know
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how many times to repeat the last literal, so append that many |
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copies to our buffer of decoded symbols (dbuf) now. (The last |
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literal used is the one at the head of the mtfSymbol array.) */ |
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if(runPos) { |
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runPos=0; |
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if(dbufCount+t>=dbufSize) return RETVAL_DATA_ERROR; |
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|
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uc = symToByte[mtfSymbol[0]]; |
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byteCount[uc] += t; |
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while(t--) dbuf[dbufCount++]=uc; |
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} |
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/* Is this the terminating symbol? */ |
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if(nextSym>symTotal) break; |
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/* At this point, nextSym indicates a new literal character. Subtract
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one to get the position in the MTF array at which this literal is |
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currently to be found. (Note that the result can't be -1 or 0, |
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because 0 and 1 are RUNA and RUNB. But another instance of the |
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first symbol in the mtf array, position 0, would have been handled |
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as part of a run above. Therefore 1 unused mtf position minus |
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2 non-literal nextSym values equals -1.) */ |
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if(dbufCount>=dbufSize) return RETVAL_DATA_ERROR; |
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i = nextSym - 1; |
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uc = mtfSymbol[i]; |
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/* Adjust the MTF array. Since we typically expect to move only a
|
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* small number of symbols, and are bound by 256 in any case, using |
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* memmove here would typically be bigger and slower due to function |
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* call overhead and other assorted setup costs. */ |
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do { |
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mtfSymbol[i] = mtfSymbol[i-1]; |
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} while (--i); |
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mtfSymbol[0] = uc; |
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uc=symToByte[uc]; |
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/* We have our literal byte. Save it into dbuf. */ |
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byteCount[uc]++; |
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dbuf[dbufCount++] = (unsigned int)uc; |
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} |
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/* At this point, we've read all the huffman-coded symbols (and repeated
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runs) for this block from the input stream, and decoded them into the |
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intermediate buffer. There are dbufCount many decoded bytes in dbuf[]. |
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Now undo the Burrows-Wheeler transform on dbuf. |
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See http://dogma.net/markn/articles/bwt/bwt.htm
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*/ |
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/* Turn byteCount into cumulative occurrence counts of 0 to n-1. */ |
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j=0; |
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for(i=0;i<256;i++) { |
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k=j+byteCount[i]; |
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byteCount[i] = j; |
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j=k; |
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} |
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/* Figure out what order dbuf would be in if we sorted it. */ |
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for (i=0;i<dbufCount;i++) { |
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uc=(unsigned char)(dbuf[i] & 0xff); |
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dbuf[byteCount[uc]] |= (i << 8); |
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byteCount[uc]++; |
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} |
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/* Decode first byte by hand to initialize "previous" byte. Note that it
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doesn't get output, and if the first three characters are identical |
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it doesn't qualify as a run (hence writeRunCountdown=5). */ |
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if(dbufCount) { |
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if(origPtr>=dbufCount) return RETVAL_DATA_ERROR; |
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bd->writePos=dbuf[origPtr]; |
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bd->writeCurrent=(unsigned char)(bd->writePos&0xff); |
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bd->writePos>>=8; |
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bd->writeRunCountdown=5; |
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} |
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bd->writeCount=dbufCount; |
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return RETVAL_OK; |
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} |
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|
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/* Undo burrows-wheeler transform on intermediate buffer to produce output.
|
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If start_bunzip was initialized with out_fd=-1, then up to len bytes of |
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data are written to outbuf. Return value is number of bytes written or |
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error (all errors are negative numbers). If out_fd!=-1, outbuf and len |
|||
are ignored, data is written to out_fd and return is RETVAL_OK or error. |
|||
*/ |
|||
|
|||
int read_bunzip(bunzip_data *bd, char *outbuf, int len) |
|||
{ |
|||
const unsigned int *dbuf; |
|||
int pos,current,previous,gotcount; |
|||
|
|||
/* If last read was short due to end of file, return last block now */ |
|||
if(bd->writeCount<0) return bd->writeCount; |
|||
|
|||
gotcount = 0; |
|||
dbuf=bd->dbuf; |
|||
pos=bd->writePos; |
|||
current=bd->writeCurrent; |
|||
|
|||
/* We will always have pending decoded data to write into the output
|
|||
buffer unless this is the very first call (in which case we haven't |
|||
huffman-decoded a block into the intermediate buffer yet). */ |
|||
|
|||
if (bd->writeCopies) { |
|||
/* Inside the loop, writeCopies means extra copies (beyond 1) */ |
|||
--bd->writeCopies; |
|||
/* Loop outputting bytes */ |
|||
for(;;) { |
|||
/* If the output buffer is full, snapshot state and return */ |
|||
if(gotcount >= len) { |
|||
bd->writePos=pos; |
|||
bd->writeCurrent=current; |
|||
bd->writeCopies++; |
|||
return len; |
|||
} |
|||
/* Write next byte into output buffer, updating CRC */ |
|||
outbuf[gotcount++] = current; |
|||
bd->writeCRC=(((bd->writeCRC)<<8) |
|||
^bd->crc32Table[((bd->writeCRC)>>24)^current]); |
|||
/* Loop now if we're outputting multiple copies of this byte */ |
|||
if (bd->writeCopies) { |
|||
--bd->writeCopies; |
|||
continue; |
|||
} |
|||
decode_next_byte: |
|||
if (!bd->writeCount--) break; |
|||
/* Follow sequence vector to undo Burrows-Wheeler transform */ |
|||
previous=current; |
|||
pos=dbuf[pos]; |
|||
current=pos&0xff; |
|||
pos>>=8; |
|||
/* After 3 consecutive copies of the same byte, the 4th is a repeat
|
|||
count. We count down from 4 instead |
|||
* of counting up because testing for non-zero is faster */ |
|||
if(--bd->writeRunCountdown) { |
|||
if(current!=previous) bd->writeRunCountdown=4; |
|||
} else { |
|||
/* We have a repeated run, this byte indicates the count */ |
|||
bd->writeCopies=current; |
|||
current=previous; |
|||
bd->writeRunCountdown=5; |
|||
/* Sometimes there are just 3 bytes (run length 0) */ |
|||
if(!bd->writeCopies) goto decode_next_byte; |
|||
/* Subtract the 1 copy we'd output anyway to get extras */ |
|||
--bd->writeCopies; |
|||
} |
|||
} |
|||
/* Decompression of this block completed successfully */ |
|||
bd->writeCRC=~bd->writeCRC; |
|||
bd->totalCRC=((bd->totalCRC<<1) | (bd->totalCRC>>31)) ^ bd->writeCRC; |
|||
/* If this block had a CRC error, force file level CRC error. */ |
|||
if(bd->writeCRC!=bd->headerCRC) { |
|||
bd->totalCRC=bd->headerCRC+1; |
|||
return RETVAL_LAST_BLOCK; |
|||
} |
|||
} |
|||
|
|||
/* Refill the intermediate buffer by huffman-decoding next block of input */ |
|||
/* (previous is just a convenient unused temp variable here) */ |
|||
previous=get_next_block(bd); |
|||
if(previous) { |
|||
bd->writeCount=previous; |
|||
return (previous!=RETVAL_LAST_BLOCK) ? previous : gotcount; |
|||
} |
|||
bd->writeCRC=0xffffffffUL; |
|||
pos=bd->writePos; |
|||
current=bd->writeCurrent; |
|||
goto decode_next_byte; |
|||
} |
|||
|
|||
/* Allocate the structure, read file header. If in_fd==-1, inbuf must contain
|
|||
a complete bunzip file (len bytes long). If in_fd!=-1, inbuf and len are |
|||
ignored, and data is read from file handle into temporary buffer. */ |
|||
int start_bunzip(bunzip_data **bdp, int in_fd, char *inbuf, int len) |
|||
{ |
|||
bunzip_data *bd; |
|||
unsigned int i,j,c; |
|||
const unsigned int BZh0=(((unsigned int)'B')<<24)+(((unsigned int)'Z')<<16) |
|||
+(((unsigned int)'h')<<8)+(unsigned int)'0'; |
|||
|
|||
/* Figure out how much data to allocate */ |
|||
i=sizeof(bunzip_data); |
|||
if(in_fd!=-1) i+=IOBUF_SIZE; |
|||
/* Allocate bunzip_data. Most fields initialize to zero. */ |
|||
if(!(bd=*bdp=(bunzip_data*)malloc(i))) return RETVAL_OUT_OF_MEMORY; |
|||
memset(bd,0,sizeof(bunzip_data)); |
|||
/* Setup input buffer */ |
|||
if(-1==(bd->in_fd=in_fd)) { |
|||
bd->inbuf=(unsigned char*)inbuf; |
|||
bd->inbufCount=len; |
|||
} else bd->inbuf=(unsigned char *)(bd+1); |
|||
/* Init the CRC32 table (big endian) */ |
|||
for(i=0;i<256;i++) { |
|||
c=i<<24; |
|||
for(j=8;j;j--) |
|||
c=c&0x80000000 ? (c<<1)^0x04c11db7 : (c<<1); |
|||
bd->crc32Table[i]=c; |
|||
} |
|||
/* Setup for I/O error handling via longjmp */ |
|||
i=setjmp(bd->jmpbuf); |
|||
if(i) return i; |
|||
|
|||
/* Ensure that file starts with "BZh['1'-'9']." */ |
|||
i = get_bits(bd,32); |
|||
if (((unsigned int)(i-BZh0-1)) >= 9) return RETVAL_NOT_BZIP_DATA; |
|||
|
|||
/* Fourth byte (ascii '1'-'9'), indicates block size in units of 100k of
|
|||
uncompressed data. Allocate intermediate buffer for block. */ |
|||
bd->dbufSize=100000*(i-BZh0); |
|||
|
|||
if(!(bd->dbuf=(unsigned int*)malloc(bd->dbufSize * sizeof(int)))) |
|||
return RETVAL_OUT_OF_MEMORY; |
|||
return RETVAL_OK; |
|||
} |
|||
|
|||
/* Example usage: decompress src_fd to dst_fd. (Stops at end of bzip data,
|
|||
not end of file.) */ |
|||
extern int uncompressStream(int src_fd, int dst_fd) |
|||
{ |
|||
char *outbuf; |
|||
bunzip_data *bd; |
|||
int i; |
|||
|
|||
if(!(outbuf=(char*)malloc(IOBUF_SIZE))) return RETVAL_OUT_OF_MEMORY; |
|||
if(!(i=start_bunzip(&bd,src_fd,0,0))) { |
|||
for(;;) { |
|||
if((i=read_bunzip(bd,outbuf,IOBUF_SIZE)) <= 0) break; |
|||
if(i!=write(dst_fd,outbuf,i)) { |
|||
i=RETVAL_UNEXPECTED_OUTPUT_EOF; |
|||
break; |
|||
} |
|||
} |
|||
} |
|||
/* Check CRC and release memory */ |
|||
if(i==RETVAL_LAST_BLOCK && bd->headerCRC==bd->totalCRC) i=RETVAL_OK; |
|||
if(bd->dbuf) free(bd->dbuf); |
|||
free(bd); |
|||
free(outbuf); |
|||
return i; |
|||
} |
|||
|
|||
#ifdef TESTING |
|||
|
|||
static char * const bunzip_errors[]={NULL,"Bad file checksum","Not bzip data", |
|||
"Unexpected input EOF","Unexpected output EOF","Data error", |
|||
"Out of memory","Obsolete (pre 0.9.5) bzip format not supported."}; |
|||
|
|||
/* Dumb little test thing, decompress stdin to stdout */ |
|||
int main(int argc, char *argv[]) |
|||
{ |
|||
int i=uncompressStream(0,1); |
|||
char c; |
|||
|
|||
if(i) fprintf(stderr,"%s\n", bunzip_errors[-i]); |
|||
else if(read(0,&c,1)) fprintf(stderr,"Trailing garbage ignored\n"); |
|||
return -i; |
|||
} |
|||
#endif |
|||
@ -0,0 +1,98 @@ |
|||
/* vi: set sw=4 ts=4: */ |
|||
/* Small bzip2 deflate implementation, by Rob Landley (rob@landley.net).
|
|||
|
|||
Based on bzip2 decompression code by Julian R Seward (jseward@acm.org), |
|||
which also acknowledges contributions by Mike Burrows, David Wheeler, |
|||
Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten, |
|||
Robert Sedgewick, and Jon L. Bentley. |
|||
|
|||
This code is licensed under the LGPLv2: |
|||
LGPL (http://www.gnu.org/copyleft/lgpl.html
|
|||
*/ |
|||
|
|||
/*
|
|||
Size and speed optimizations by Manuel Novoa III (mjn3@codepoet.org). |
|||
|
|||
More efficient reading of huffman codes, a streamlined read_bunzip() |
|||
function, and various other tweaks. In (limited) tests, approximately |
|||
20% faster than bzcat on x86 and about 10% faster on arm. |
|||
|
|||
Note that about 2/3 of the time is spent in read_unzip() reversing |
|||
the Burrows-Wheeler transformation. Much of that time is delay |
|||
resulting from cache misses. |
|||
|
|||
I would ask that anyone benefiting from this work, especially those |
|||
using it in commercial products, consider making a donation to my local |
|||
non-profit hospice organization (see www.hospiceacadiana.com) in the |
|||
name of the woman I loved, Toni W. Hagan, who passed away Feb. 12, 2003. |
|||
|
|||
Manuel |
|||
*/ |
|||
|
|||
/* Modified by Macoy Madson:
|
|||
- Give no errors with a C++ compiler (all -fpermissive errors) |
|||
- Add header file |
|||
*/ |
|||
|
|||
#include <setjmp.h> |
|||
|
|||
/* Constants for huffman coding */ |
|||
#define MAX_GROUPS 6 |
|||
#define GROUP_SIZE 50 /* 64 would have been more efficient */ |
|||
#define MAX_HUFCODE_BITS 20 /* Longest huffman code allowed */ |
|||
#define MAX_SYMBOLS 258 /* 256 literals + RUNA + RUNB */ |
|||
#define SYMBOL_RUNA 0 |
|||
#define SYMBOL_RUNB 1 |
|||
|
|||
/* Status return values */ |
|||
#define RETVAL_OK 0 |
|||
#define RETVAL_LAST_BLOCK (-1) |
|||
#define RETVAL_NOT_BZIP_DATA (-2) |
|||
#define RETVAL_UNEXPECTED_INPUT_EOF (-3) |
|||
#define RETVAL_UNEXPECTED_OUTPUT_EOF (-4) |
|||
#define RETVAL_DATA_ERROR (-5) |
|||
#define RETVAL_OUT_OF_MEMORY (-6) |
|||
#define RETVAL_OBSOLETE_INPUT (-7) |
|||
|
|||
/* Other housekeeping constants */ |
|||
#define IOBUF_SIZE 4096 |
|||
|
|||
/* This is what we know about each huffman coding group */ |
|||
struct group_data { |
|||
/* We have an extra slot at the end of limit[] for a sentinal value. */ |
|||
int limit[MAX_HUFCODE_BITS+1],base[MAX_HUFCODE_BITS],permute[MAX_SYMBOLS]; |
|||
int minLen, maxLen; |
|||
}; |
|||
|
|||
/* Structure holding all the housekeeping data, including IO buffers and
|
|||
memory that persists between calls to bunzip */ |
|||
typedef struct { |
|||
/* State for interrupting output loop */ |
|||
int writeCopies,writePos,writeRunCountdown,writeCount,writeCurrent; |
|||
/* I/O tracking data (file handles, buffers, positions, etc.) */ |
|||
int in_fd,out_fd,inbufCount,inbufPos /*,outbufPos*/; |
|||
unsigned char *inbuf /*,*outbuf*/; |
|||
unsigned int inbufBitCount, inbufBits; |
|||
/* The CRC values stored in the block header and calculated from the data */ |
|||
unsigned int crc32Table[256],headerCRC, totalCRC, writeCRC; |
|||
/* Intermediate buffer and its size (in bytes) */ |
|||
unsigned int *dbuf, dbufSize; |
|||
/* These things are a bit too big to go on the stack */ |
|||
unsigned char selectors[32768]; /* nSelectors=15 bits */ |
|||
struct group_data groups[MAX_GROUPS]; /* huffman coding tables */ |
|||
/* For I/O error handling */ |
|||
jmp_buf jmpbuf; |
|||
} bunzip_data; |
|||
|
|||
/* Allocate the structure, read file header. If in_fd==-1, inbuf must contain
|
|||
a complete bunzip file (len bytes long). If in_fd!=-1, inbuf and len are |
|||
ignored, and data is read from file handle into temporary buffer. */ |
|||
int start_bunzip(bunzip_data **bdp, int in_fd, char *inbuf, int len); |
|||
|
|||
/* Undo burrows-wheeler transform on intermediate buffer to produce output.
|
|||
If start_bunzip was initialized with out_fd=-1, then up to len bytes of |
|||
data are written to outbuf. Return value is number of bytes written or |
|||
error (all errors are negative numbers). If out_fd!=-1, outbuf and len |
|||
are ignored, data is written to out_fd and return is RETVAL_OK or error. |
|||
*/ |
|||
int read_bunzip(bunzip_data *bd, char *outbuf, int len); |
|||
Loading…
Reference in new issue