toybox: lib/bunzip.c annotate

annotate lib/bunzip.c @ 387:67b0ded3c56c

Add dirname, and typo fixes to wc header.

author	Rob Landley <rob@landley.net>
date	Fri, 18 Nov 2011 06:21:29 -0600
parents	aaafa1ceaa91
children	786841fdb1e0

rev	line source
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	1 /* vi: set sw=4 ts=4: */
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	2 /* micro-bunzip, a small, simple bzip2 decompression implementation.
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	3
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	4 Copyright 2003, 2006 by Rob Landley (rob@landley.net).
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	5
54 60a7fb8ddeb4 Add a quick and dirt bzcat (stdin to stdout only for the moment) to test Rob Landley <rob@landley.net> parents: 46 diff changeset	6 Based on a close reading (but not the actual code) of the original bzip2
60a7fb8ddeb4 Add a quick and dirt bzcat (stdin to stdout only for the moment) to test Rob Landley <rob@landley.net> parents: 46 diff changeset	7 decompression code by Julian R Seward (jseward@acm.org), which also
60a7fb8ddeb4 Add a quick and dirt bzcat (stdin to stdout only for the moment) to test Rob Landley <rob@landley.net> parents: 46 diff changeset	8 acknowledges contributions by Mike Burrows, David Wheeler, Peter Fenwick,
60a7fb8ddeb4 Add a quick and dirt bzcat (stdin to stdout only for the moment) to test Rob Landley <rob@landley.net> parents: 46 diff changeset	9 Alistair Moffat, Radford Neal, Ian H. Witten, Robert Sedgewick, and
60a7fb8ddeb4 Add a quick and dirt bzcat (stdin to stdout only for the moment) to test Rob Landley <rob@landley.net> parents: 46 diff changeset	10 Jon L. Bentley.
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	11 */
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	12
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	13 #include "toys.h"
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	14
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	15 #define THREADS 1
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	16
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	17 // Constants for huffman coding
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	18 #define MAX_GROUPS 6
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	19 #define GROUP_SIZE 50 /* 64 would have been more efficient */
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	20 #define MAX_HUFCODE_BITS 20 /* Longest huffman code allowed */
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	21 #define MAX_SYMBOLS 258 /* 256 literals + RUNA + RUNB */
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	22 #define SYMBOL_RUNA 0
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	23 #define SYMBOL_RUNB 1
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	24
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	25 // Other housekeeping constants
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	26 #define IOBUF_SIZE 4096
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	27
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	28 // Status return values
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	29 #define RETVAL_LAST_BLOCK (-100)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	30 #define RETVAL_NOT_BZIP_DATA (-1)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	31 #define RETVAL_DATA_ERROR (-2)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	32 #define RETVAL_OBSOLETE_INPUT (-3)
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	33
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	34 char *bunzip_errors[]={
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	35 NULL,
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	36 "Not bzip data",
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	37 "Data error",
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	38 "Obsolete (pre 0.9.5) bzip format not supported."
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	39 };
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	40
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	41 // This is what we know about each huffman coding group
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	42 struct group_data {
62 f41f997c1e73 More optimizations originally suggested by Manuel Nova: Use a sentinel value Rob Landley <rob@landley.net> parents: 61 diff changeset	43 int limit[MAX_HUFCODE_BITS+1], base[MAX_HUFCODE_BITS], permute[MAX_SYMBOLS];
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	44 char minLen, maxLen;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	45 };
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	46
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	47 // Data for burrows wheeler transform
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	48
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	49 struct bwdata {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	50 unsigned int origPtr;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	51 int byteCount[256];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	52 // State saved when interrupting output
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	53 int writePos, writeRun, writeCount, writeCurrent;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	54 unsigned int dataCRC, headerCRC;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	55 unsigned int *dbuf;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	56 };
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	57
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	58 // Structure holding all the housekeeping data, including IO buffers and
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	59 // memory that persists between calls to bunzip
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	60 struct bunzip_data {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	61
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	62 // Input stream, input buffer, input bit buffer
46 5a6241f16e95 Remove more warnings. Rob Landley <rob@landley.net> parents: 40 diff changeset	63 int in_fd, inbufCount, inbufPos;
5a6241f16e95 Remove more warnings. Rob Landley <rob@landley.net> parents: 40 diff changeset	64 char *inbuf;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	65 unsigned int inbufBitCount, inbufBits;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	66
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	67 // Output buffer
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	68 char outbuf[IOBUF_SIZE];
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	69 int outbufPos;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	70
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	71 unsigned int totalCRC;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	72
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	73 // First pass decompression data (Huffman and MTF decoding)
46 5a6241f16e95 Remove more warnings. Rob Landley <rob@landley.net> parents: 40 diff changeset	74 char selectors[32768]; // nSelectors=15 bits
5a6241f16e95 Remove more warnings. Rob Landley <rob@landley.net> parents: 40 diff changeset	75 struct group_data groups[MAX_GROUPS]; // huffman coding tables
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	76 int symTotal, groupCount, nSelectors;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	77 unsigned char symToByte[256], mtfSymbol[256];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	78
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	79 // The CRC values stored in the block header and calculated from the data
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	80 unsigned int crc32Table[256];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	81
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	82 // Second pass decompression data (burrows-wheeler transform)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	83 unsigned int dbufSize;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	84 struct bwdata bwdata[THREADS];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	85 };
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	86
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	87 // Return the next nnn bits of input. All reads from the compressed input
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	88 // are done through this function. All reads are big endian.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	89 static unsigned int get_bits(struct bunzip_data *bd, char bits_wanted)
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	90 {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	91 unsigned int bits = 0;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	92
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	93 // If we need to get more data from the byte buffer, do so. (Loop getting
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	94 // one byte at a time to enforce endianness and avoid unaligned access.)
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	95 while (bd->inbufBitCount < bits_wanted) {
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	96
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	97 // If we need to read more data from file into byte buffer, do so
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	98 if (bd->inbufPos == bd->inbufCount) {
40 d046f8d1401e Trawling through the archives: a broken test, an unnecessary memset, and a Rob Landley <rob@landley.net> parents: 39 diff changeset	99 if (0 >= (bd->inbufCount = read(bd->in_fd, bd->inbuf, IOBUF_SIZE)))
64 67ee3a0b76e1 In bunzip replace setjmp/longjmp handling with error_exit(), replace string Rob Landley <rob@landley.net> parents: 62 diff changeset	100 error_exit("Unexpected input EOF");
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	101 bd->inbufPos = 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	102 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	103
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	104 // Avoid 32-bit overflow (dump bit buffer to top of output)
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	105 if (bd->inbufBitCount>=24) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	106 bits = bd->inbufBits&((1<<bd->inbufBitCount)-1);
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	107 bits_wanted -= bd->inbufBitCount;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	108 bits <<= bits_wanted;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	109 bd->inbufBitCount = 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	110 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	111
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	112 // Grab next 8 bits of input from buffer.
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	113 bd->inbufBits = (bd->inbufBits<<8) \| bd->inbuf[bd->inbufPos++];
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	114 bd->inbufBitCount += 8;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	115 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	116
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	117 // Calculate result
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	118 bd->inbufBitCount -= bits_wanted;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	119 bits \|= (bd->inbufBits>>bd->inbufBitCount) & ((1<<bits_wanted)-1);
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	120
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	121 return bits;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	122 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	123
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	124 /* Read block header at start of a new compressed data block. Consists of:
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	125 *
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	126 * 48 bits : Block signature, either pi (data block) or e (EOF block).
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	127 * 32 bits : bw->headerCRC
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	128 * 1 bit : obsolete feature flag.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	129 * 24 bits : origPtr (Burrows-wheeler unwind index, only 20 bits ever used)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	130 * 16 bits : Mapping table index.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	131 *[16 bits]: symToByte[symTotal] (Mapping table. For each bit set in mapping
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	132 * table index above, read another 16 bits of mapping table data.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	133 * If correspondig bit is unset, all bits in that mapping table
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	134 * section are 0.)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	135 * 3 bits : groupCount (how many huffman tables used to encode, anywhere
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	136 * from 2 to MAX_GROUPS)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	137 * variable: hufGroup[groupCount] (MTF encoded huffman table data.)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	138 */
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	139
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	140 static int read_block_header(struct bunzip_data bd, struct bwdata bw)
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	141 {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	142 struct group_data *hufGroup;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	143 int hh, ii, jj, kk, symCount, base, limit;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	144 unsigned char uc;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	145
64 67ee3a0b76e1 In bunzip replace setjmp/longjmp handling with error_exit(), replace string Rob Landley <rob@landley.net> parents: 62 diff changeset	146 // Read in header signature and CRC (which is stored big endian)
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	147 ii = get_bits(bd, 24);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	148 jj = get_bits(bd, 24);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	149 bw->headerCRC = get_bits(bd,32);
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	150
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	151 // Is this the EOF block with CRC for whole file? (Constant is "e")
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	152 if (ii==0x177245 && jj==0x385090) return RETVAL_LAST_BLOCK;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	153
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	154 // Is this a valid data block? (Constant is "pi".)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	155 if (ii!=0x314159 \|\| jj!=0x265359) return RETVAL_NOT_BZIP_DATA;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	156
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	157 // We can add support for blockRandomised if anybody complains.
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	158 if (get_bits(bd,1)) return RETVAL_OBSOLETE_INPUT;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	159 if ((bw->origPtr = get_bits(bd,24)) > bd->dbufSize)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	160 return RETVAL_DATA_ERROR;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	161
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	162 // mapping table: if some byte values are never used (encoding things
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	163 // like ascii text), the compression code removes the gaps to have fewer
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	164 // symbols to deal with, and writes a sparse bitfield indicating which
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	165 // values were present. We make a translation table to convert the symbols
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	166 // back to the corresponding bytes.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	167 hh = get_bits(bd, 16);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	168 bd->symTotal = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	169 for (ii=0; ii<16; ii++) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	170 if (hh & (1 << (15 - ii))) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	171 kk = get_bits(bd, 16);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	172 for (jj=0; jj<16; jj++)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	173 if (kk & (1 << (15 - jj)))
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	174 bd->symToByte[bd->symTotal++] = (16 * ii) + jj;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	175 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	176 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	177
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	178 // How many different huffman coding groups does this block use?
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	179 bd->groupCount = get_bits(bd,3);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	180 if (bd->groupCount<2 \|\| bd->groupCount>MAX_GROUPS) return RETVAL_DATA_ERROR;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	181
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	182 // nSelectors: Every GROUP_SIZE many symbols we switch huffman coding
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	183 // tables. Each group has a selector, which is an index into the huffman
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	184 // coding table arrays.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	185 //
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	186 // Read in the group selector array, which is stored as MTF encoded
56 7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	187 // bit runs. (MTF = Move To Front. Every time a symbol occurs it's moved
7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	188 // to the front of the table, so it has a shorter encoding next time.)
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	189 if (!(bd->nSelectors = get_bits(bd, 15))) return RETVAL_DATA_ERROR;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	190 for (ii=0; ii<bd->groupCount; ii++) bd->mtfSymbol[ii] = ii;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	191 for (ii=0; ii<bd->nSelectors; ii++) {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	192
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	193 // Get next value
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	194 for(jj=0;get_bits(bd,1);jj++)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	195 if (jj>=bd->groupCount) return RETVAL_DATA_ERROR;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	196
56 7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	197 // Decode MTF to get the next selector, and move it to the front.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	198 uc = bd->mtfSymbol[jj];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	199 memmove(bd->mtfSymbol+1, bd->mtfSymbol, jj);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	200 bd->mtfSymbol[0] = bd->selectors[ii] = uc;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	201 }
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	202
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	203 // Read the huffman coding tables for each group, which code for symTotal
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	204 // literal symbols, plus two run symbols (RUNA, RUNB)
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	205 symCount = bd->symTotal+2;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	206 for (jj=0; jj<bd->groupCount; jj++) {
305 b094b81830b0 A pathological case of huffman coding that uses 8 bits to code each of 256 Rob Landley <rob@landley.net> parents: 233 diff changeset	207 unsigned char length[MAX_SYMBOLS];
b094b81830b0 A pathological case of huffman coding that uses 8 bits to code each of 256 Rob Landley <rob@landley.net> parents: 233 diff changeset	208 unsigned temp[MAX_HUFCODE_BITS+1];
b094b81830b0 A pathological case of huffman coding that uses 8 bits to code each of 256 Rob Landley <rob@landley.net> parents: 233 diff changeset	209 int minLen, maxLen, pp;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	210
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	211 // Read lengths
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	212 hh = get_bits(bd, 5);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	213 for (ii = 0; ii < symCount; ii++) {
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	214 for(;;) {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	215 // !hh \|\| hh > MAX_HUFCODE_BITS in one test.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	216 if (MAX_HUFCODE_BITS-1 < (unsigned)hh-1)
57 034de958ee65 Fix off by one error in a test. Rob Landley <rob@landley.net> parents: 56 diff changeset	217 return RETVAL_DATA_ERROR;
67 b6646155e924 Another suggestion from Manuel: Grab 2 bits instead of 1 inside a loop. Saves Rob Landley <rob@landley.net> parents: 64 diff changeset	218 // Grab 2 bits instead of 1 (slightly smaller/faster). Stop if
b6646155e924 Another suggestion from Manuel: Grab 2 bits instead of 1 inside a loop. Saves Rob Landley <rob@landley.net> parents: 64 diff changeset	219 // first bit is 0, otherwise second bit says whether to
b6646155e924 Another suggestion from Manuel: Grab 2 bits instead of 1 inside a loop. Saves Rob Landley <rob@landley.net> parents: 64 diff changeset	220 // increment or decrement.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	221 kk = get_bits(bd, 2);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	222 if (kk & 2) hh += 1 - ((kk&1)<<1);
67 b6646155e924 Another suggestion from Manuel: Grab 2 bits instead of 1 inside a loop. Saves Rob Landley <rob@landley.net> parents: 64 diff changeset	223 else {
b6646155e924 Another suggestion from Manuel: Grab 2 bits instead of 1 inside a loop. Saves Rob Landley <rob@landley.net> parents: 64 diff changeset	224 bd->inbufBitCount++;
b6646155e924 Another suggestion from Manuel: Grab 2 bits instead of 1 inside a loop. Saves Rob Landley <rob@landley.net> parents: 64 diff changeset	225 break;
b6646155e924 Another suggestion from Manuel: Grab 2 bits instead of 1 inside a loop. Saves Rob Landley <rob@landley.net> parents: 64 diff changeset	226 }
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	227 }
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	228 length[ii] = hh;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	229 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	230
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	231 // Find largest and smallest lengths in this group
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	232 minLen = maxLen = length[0];
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	233 for (ii = 1; ii < symCount; ii++) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	234 if(length[ii] > maxLen) maxLen = length[ii];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	235 else if(length[ii] < minLen) minLen = length[ii];
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	236 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	237
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	238 /* Calculate permute[], base[], and limit[] tables from length[].
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	239 *
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	240 * permute[] is the lookup table for converting huffman coded symbols
68 7b89650905c0 Merge two similar loops and expand a comment. Rob Landley <rob@landley.net> parents: 67 diff changeset	241 * into decoded symbols. It contains symbol values sorted by length.
156 1e8f4b05cb65 Remove trailing whitespace (thanks to Charlie Shepherd), and a couple comment Rob Landley <rob@landley.net> parents: 94 diff changeset	242 *
68 7b89650905c0 Merge two similar loops and expand a comment. Rob Landley <rob@landley.net> parents: 67 diff changeset	243 * base[] is the amount to subtract from the value of a huffman symbol
7b89650905c0 Merge two similar loops and expand a comment. Rob Landley <rob@landley.net> parents: 67 diff changeset	244 * of a given length when using permute[].
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	245 *
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	246 * limit[] indicates the largest numerical value a symbol with a given
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	247 * number of bits can have. It lets us know when to stop reading.
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	248 *
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	249 * To use these, keep reading bits until value <= limit[bitcount] or
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	250 * you've read over 20 bits (error). Then the decoded symbol
56 7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	251 * equals permute[hufcode_value - base[hufcode_bitcount]].
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	252 */
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	253 hufGroup = bd->groups+jj;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	254 hufGroup->minLen = minLen;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	255 hufGroup->maxLen = maxLen;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	256
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	257 // Note that minLen can't be smaller than 1, so we adjust the base
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	258 // and limit array pointers so we're not always wasting the first
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	259 // entry. We do this again when using them (during symbol decoding).
56 7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	260 base = hufGroup->base-1;
7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	261 limit = hufGroup->limit-1;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	262
233 d4176f3f3835 Zap toys/Config.in and instead create generated/Config.in from contents of Rob Landley <rob@landley.net> parents: 215 diff changeset	263 // zero temp[] and limit[], and calculate permute[]
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	264 pp = 0;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	265 for (ii = minLen; ii <= maxLen; ii++) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	266 temp[ii] = limit[ii] = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	267 for (hh = 0; hh < symCount; hh++)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	268 if (length[hh] == ii)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	269 hufGroup->permute[pp++] = hh;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	270 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	271
68 7b89650905c0 Merge two similar loops and expand a comment. Rob Landley <rob@landley.net> parents: 67 diff changeset	272 // Count symbols coded for at each bit length
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	273 for (ii = 0; ii < symCount; ii++) temp[length[ii]]++;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	274
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	275 /* Calculate limit[] (the largest symbol-coding value at each bit
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	276 * length, which is (previous limit<<1)+symbols at this level), and
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	277 * base[] (number of symbols to ignore at each bit length, which is
68 7b89650905c0 Merge two similar loops and expand a comment. Rob Landley <rob@landley.net> parents: 67 diff changeset	278 * limit minus the cumulative count of symbols coded for already). */
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	279 pp = hh = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	280 for (ii = minLen; ii < maxLen; ii++) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	281 pp += temp[ii];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	282 limit[ii] = pp-1;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	283 pp <<= 1;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	284 base[ii+1] = pp-(hh+=temp[ii]);
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	285 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	286 limit[maxLen] = pp+temp[maxLen]-1;
62 f41f997c1e73 More optimizations originally suggested by Manuel Nova: Use a sentinel value Rob Landley <rob@landley.net> parents: 61 diff changeset	287 limit[maxLen+1] = INT_MAX;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	288 base[minLen] = 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	289 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	290
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	291 return 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	292 }
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	293
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	294 /* First pass, read block's symbols into dbuf[dbufCount].
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	295 *
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	296 * This undoes three types of compression: huffman coding, run length encoding,
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	297 * and move to front encoding. We have to undo all those to know when we've
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	298 * read enough input.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	299 */
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	300
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	301 static int read_huffman_data(struct bunzip_data bd, struct bwdata bw)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	302 {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	303 struct group_data *hufGroup;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	304 int hh, ii, jj, kk, runPos, dbufCount, symCount, selector, nextSym,
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	305 byteCount, base, *limit;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	306 unsigned int *dbuf = bw->dbuf;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	307 unsigned char uc;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	308
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	309 // We've finished reading and digesting the block header. Now read this
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	310 // block's huffman coded symbols from the file and undo the huffman coding
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	311 // and run length encoding, saving the result into dbuf[dbufCount++] = uc
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	312
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	313 // Initialize symbol occurrence counters and symbol mtf table
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	314 byteCount = bw->byteCount;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	315 for(ii=0; ii<256; ii++) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	316 byteCount[ii] = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	317 bd->mtfSymbol[ii] = ii;
69 530168fc253f Merge a memset with an existing loop, tweak comments. Rob Landley <rob@landley.net> parents: 68 diff changeset	318 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	319
56 7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	320 // Loop through compressed symbols. This is the first "tight inner loop"
7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	321 // that needs to be micro-optimized for speed. (This one fills out dbuf[]
7794562e2e64 Comment and whitespace changes. Rob Landley <rob@landley.net> parents: 55 diff changeset	322 // linearly, staying in cache more, so isn't as limited by DRAM access.)
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	323 runPos = dbufCount = symCount = selector = 0;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	324 // Some unnecessary initializations to shut gcc up.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	325 base = limit = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	326 hufGroup = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	327 hh = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	328
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	329 for (;;) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	330
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	331 // Have we reached the end of this huffman group?
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	332 if (!(symCount--)) {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	333 // Determine which huffman coding group to use.
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	334 symCount = GROUP_SIZE-1;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	335 if (selector >= bd->nSelectors) return RETVAL_DATA_ERROR;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	336 hufGroup = bd->groups + bd->selectors[selector++];
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	337 base = hufGroup->base-1;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	338 limit = hufGroup->limit-1;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	339 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	340
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	341 // Read next huffman-coded symbol (into jj).
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	342 ii = hufGroup->minLen;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	343 jj = get_bits(bd, ii);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	344 while (jj > limit[ii]) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	345 // if (ii > hufGroup->maxLen) return RETVAL_DATA_ERROR;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	346 ii++;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	347
62 f41f997c1e73 More optimizations originally suggested by Manuel Nova: Use a sentinel value Rob Landley <rob@landley.net> parents: 61 diff changeset	348 // Unroll get_bits() to avoid a function call when the data's in
f41f997c1e73 More optimizations originally suggested by Manuel Nova: Use a sentinel value Rob Landley <rob@landley.net> parents: 61 diff changeset	349 // the buffer already.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	350 kk = bd->inbufBitCount
62 f41f997c1e73 More optimizations originally suggested by Manuel Nova: Use a sentinel value Rob Landley <rob@landley.net> parents: 61 diff changeset	351 ? (bd->inbufBits >> --(bd->inbufBitCount)) & 1
f41f997c1e73 More optimizations originally suggested by Manuel Nova: Use a sentinel value Rob Landley <rob@landley.net> parents: 61 diff changeset	352 : get_bits(bd, 1);
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	353 jj = (jj << 1) \| kk;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	354 }
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	355 // Huffman decode jj into nextSym (with bounds checking)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	356 jj-=base[ii];
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	357
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	358 if (ii > hufGroup->maxLen \|\| (unsigned)jj >= MAX_SYMBOLS)
62 f41f997c1e73 More optimizations originally suggested by Manuel Nova: Use a sentinel value Rob Landley <rob@landley.net> parents: 61 diff changeset	359 return RETVAL_DATA_ERROR;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	360 nextSym = hufGroup->permute[jj];
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	361
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	362 // If this is a repeated run, loop collecting data
58 b060142aee01 Minor optimization the compiler already does for us (according to bloatcheck), Rob Landley <rob@landley.net> parents: 57 diff changeset	363 if ((unsigned)nextSym <= SYMBOL_RUNB) {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	364
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	365 // If this is the start of a new run, zero out counter
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	366 if(!runPos) {
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	367 runPos = 1;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	368 hh = 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	369 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	370
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	371 /* Neat trick that saves 1 symbol: instead of or-ing 0 or 1 at
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	372 each bit position, add 1 or 2 instead. For example,
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	373 1011 is 1<<0 + 1<<1 + 2<<2. 1010 is 2<<0 + 2<<1 + 1<<2.
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	374 You can make any bit pattern that way using 1 less symbol than
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	375 the basic or 0/1 method (except all bits 0, which would use no
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	376 symbols, but a run of length 0 doesn't mean anything in this
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	377 context). Thus space is saved. */
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	378 hh += (runPos << nextSym); // +runPos if RUNA; +2*runPos if RUNB
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	379 runPos <<= 1;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	380 continue;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	381 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	382
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	383 /* When we hit the first non-run symbol after a run, we now know
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	384 how many times to repeat the last literal, so append that many
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	385 copies to our buffer of decoded symbols (dbuf) now. (The last
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	386 literal used is the one at the head of the mtfSymbol array.) */
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	387 if (runPos) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	388 runPos = 0;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	389 if (dbufCount+hh >= bd->dbufSize) return RETVAL_DATA_ERROR;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	390
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	391 uc = bd->symToByte[bd->mtfSymbol[0]];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	392 byteCount[uc] += hh;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	393 while (hh--) dbuf[dbufCount++] = uc;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	394 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	395
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	396 // Is this the terminating symbol?
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	397 if (nextSym>bd->symTotal) break;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	398
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	399 /* At this point, the symbol we just decoded indicates a new literal
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	400 character. Subtract one to get the position in the MTF array
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	401 at which this literal is currently to be found. (Note that the
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	402 result can't be -1 or 0, because 0 and 1 are RUNA and RUNB.
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	403 Another instance of the first symbol in the mtf array, position 0,
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	404 would have been handled as part of a run.) */
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	405 if (dbufCount>=bd->dbufSize) return RETVAL_DATA_ERROR;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	406 ii = nextSym - 1;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	407 uc = bd->mtfSymbol[ii];
61 d6ece20e13ce Minor cleanups. Rob Landley <rob@landley.net> parents: 60 diff changeset	408 // On my laptop, unrolling this memmove() into a loop shaves 3.5% off
d6ece20e13ce Minor cleanups. Rob Landley <rob@landley.net> parents: 60 diff changeset	409 // the total running time.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	410 while(ii--) bd->mtfSymbol[ii+1] = bd->mtfSymbol[ii];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	411 bd->mtfSymbol[0] = uc;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	412 uc = bd->symToByte[uc];
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	413
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	414 // We have our literal byte. Save it into dbuf.
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	415 byteCount[uc]++;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	416 dbuf[dbufCount++] = (unsigned int)uc;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	417 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	418
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	419 // Now we know what dbufCount is, do a better sanity check on origPtr.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	420 if (bw->origPtr >= (bw->writeCount = dbufCount)) return RETVAL_DATA_ERROR;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	421
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	422 return 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	423 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	424
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	425 // Flush output buffer to disk
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	426 void flush_bunzip_outbuf(struct bunzip_data *bd, int out_fd)
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	427 {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	428 if (bd->outbufPos) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	429 if (write(out_fd, bd->outbuf, bd->outbufPos) != bd->outbufPos)
64 67ee3a0b76e1 In bunzip replace setjmp/longjmp handling with error_exit(), replace string Rob Landley <rob@landley.net> parents: 62 diff changeset	430 error_exit("Unexpected output EOF");
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	431 bd->outbufPos = 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	432 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	433 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	434
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	435 void burrows_wheeler_prep(struct bunzip_data bd, struct bwdata bw)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	436 {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	437 int ii, jj;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	438 unsigned int *dbuf = bw->dbuf;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	439 int *byteCount = bw->byteCount;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	440
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	441 // Technically this part is preparation for the burrows-wheeler
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	442 // transform, but it's quick and convenient to do here.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	443
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	444 // Turn byteCount into cumulative occurrence counts of 0 to n-1.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	445 jj = 0;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	446 for (ii=0; ii<256; ii++) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	447 int kk = jj + byteCount[ii];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	448 byteCount[ii] = jj;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	449 jj = kk;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	450 }
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	451
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	452 // Use occurrence counts to quickly figure out what order dbuf would be in
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	453 // if we sorted it.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	454 for (ii=0; ii < bw->writeCount; ii++) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	455 unsigned char uc = dbuf[ii];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	456 dbuf[byteCount[uc]] \|= (ii << 8);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	457 byteCount[uc]++;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	458 }
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	459
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	460 // blockRandomised support would go here.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	461
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	462 // Using ii as position, jj as previous character, hh as current character,
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	463 // and uc as run count.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	464 bw->dataCRC = 0xffffffffL;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	465
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	466 /* Decode first byte by hand to initialize "previous" byte. Note that it
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	467 doesn't get output, and if the first three characters are identical
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	468 it doesn't qualify as a run (hence uc=255, which will either wrap
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	469 to 1 or get reset). */
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	470 if (bw->writeCount) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	471 bw->writePos = dbuf[bw->origPtr];
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	472 bw->writeCurrent = (unsigned char)bw->writePos;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	473 bw->writePos >>= 8;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	474 bw->writeRun = -1;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	475 }
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	476 }
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	477
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	478 // Decompress a block of text to intermediate buffer
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	479 int read_bunzip_data(struct bunzip_data *bd)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	480 {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	481 int rc = read_block_header(bd, bd->bwdata);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	482 if (!rc) rc=read_huffman_data(bd, bd->bwdata);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	483
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	484 // First thing that can be done by a background thread.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	485 burrows_wheeler_prep(bd, bd->bwdata);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	486
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	487 return rc;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	488 }
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	489
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	490 // Undo burrows-wheeler transform on intermediate buffer to produce output.
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	491 // If !len, write up to len bytes of data to buf. Otherwise write to out_fd.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	492 // Returns len ? bytes written : 0. Notice all errors are negative #'s.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	493 //
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	494 // Burrows-wheeler transform is described at:
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	495 // http://dogma.net/markn/articles/bwt/bwt.htm
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	496 // http://marknelson.us/1996/09/01/bwt/
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	497
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	498 int write_bunzip_data(struct bunzip_data bd, struct bwdata bw, int out_fd, char *outbuf, int len)
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	499 {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	500 unsigned int *dbuf = bw->dbuf;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	501 int count, pos, current, run, copies, outbyte, previous, gotcount = 0;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	502
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	503 for (;;) {
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	504
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	505 // If last read was short due to end of file, return last block now
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	506 if (bw->writeCount < 0) return bw->writeCount;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	507
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	508 // If we need to refill dbuf, do it.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	509 if (!bw->writeCount) {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	510 int i = read_bunzip_data(bd);
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	511 if (i) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	512 if (i == RETVAL_LAST_BLOCK) {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	513 bw->writeCount = i;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	514 return gotcount;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	515 } else return i;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	516 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	517 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	518
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	519 // loop generating output
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	520 count = bw->writeCount;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	521 pos = bw->writePos;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	522 current = bw->writeCurrent;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	523 run = bw->writeRun;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	524 while (count) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	525
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	526 // If somebody (like tar) wants a certain number of bytes of
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	527 // data from memory instead of written to a file, humor them.
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	528 if (len && bd->outbufPos>=len) goto dataus_interruptus;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	529 count--;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	530
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	531 // Follow sequence vector to undo Burrows-Wheeler transform.
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	532 previous = current;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	533 pos = dbuf[pos];
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	534 current = pos&0xff;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	535 pos >>= 8;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	536
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	537 // Whenever we see 3 consecutive copies of the same byte,
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	538 // the 4th is a repeat count
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	539 if (run++ == 3) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	540 copies = current;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	541 outbyte = previous;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	542 current = -1;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	543 } else {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	544 copies = 1;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	545 outbyte = current;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	546 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	547
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	548 // Output bytes to buffer, flushing to file if necessary
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	549 while (copies--) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	550 if (bd->outbufPos == IOBUF_SIZE) flush_bunzip_outbuf(bd,out_fd);
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	551 bd->outbuf[bd->outbufPos++] = outbyte;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	552 bw->dataCRC = (bw->dataCRC << 8)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	553 ^ bd->crc32Table[(bw->dataCRC >> 24) ^ outbyte];
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	554 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	555 if (current!=previous) run=0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	556 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	557
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	558 // decompression of this block completed successfully
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	559 bw->dataCRC = ~(bw->dataCRC);
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	560 bd->totalCRC = ((bd->totalCRC << 1) \| (bd->totalCRC >> 31))
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	561 ^ bw->dataCRC;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	562
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	563 // if this block had a crc error, force file level crc error.
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	564 if (bw->dataCRC != bw->headerCRC) {
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	565 bd->totalCRC = bw->headerCRC+1;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	566
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	567 return RETVAL_LAST_BLOCK;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	568 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	569 dataus_interruptus:
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	570 bw->writeCount = count;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	571 if (len) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	572 gotcount += bd->outbufPos;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	573 memcpy(outbuf, bd->outbuf, len);
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	574
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	575 // If we got enough data, checkpoint loop state and return
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	576 if ((len-=bd->outbufPos)<1) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	577 bd->outbufPos -= len;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	578 if (bd->outbufPos)
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	579 memmove(bd->outbuf, bd->outbuf+len, bd->outbufPos);
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	580 bw->writePos = pos;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	581 bw->writeCurrent = current;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	582 bw->writeRun = run;
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	583
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	584 return gotcount;
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	585 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	586 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	587 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	588 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	589
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	590 // Allocate the structure, read file header. If !len, src_fd contains
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	591 // filehandle to read from. Else inbuf contains data.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	592 int start_bunzip(struct bunzip_data *bdp, int src_fd, char inbuf, int len)
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	593 {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	594 struct bunzip_data *bd;
334 83c461db9df7 Check in crc_init needed by cksum. (Oops.) Rob Landley <rob@landley.net> parents: 305 diff changeset	595 unsigned int i;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	596
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	597 // Figure out how much data to allocate.
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	598 i = sizeof(struct bunzip_data);
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	599 if (!len) i += IOBUF_SIZE;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	600
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	601 // Allocate bunzip_data. Most fields initialize to zero.
64 67ee3a0b76e1 In bunzip replace setjmp/longjmp handling with error_exit(), replace string Rob Landley <rob@landley.net> parents: 62 diff changeset	602 bd = *bdp = xzalloc(i);
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	603 if (len) {
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	604 bd->inbuf = inbuf;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	605 bd->inbufCount = len;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	606 bd->in_fd = -1;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	607 } else {
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	608 bd->inbuf = (char *)(bd+1);
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	609 bd->in_fd = src_fd;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	610 }
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	611
337 aaafa1ceaa91 Add -N, -I, -L, and -P options to cksum. Rob Landley <rob@landley.net> parents: 334 diff changeset	612 crc_init(bd->crc32Table, 0);
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	613
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	614 // Ensure that file starts with "BZh".
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	615 for (i=0;i<3;i++)
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	616 if (get_bits(bd,8)!="BZh"[i]) return RETVAL_NOT_BZIP_DATA;
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	617
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	618 // Next byte ascii '1'-'9', indicates block size in units of 100k of
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	619 // uncompressed data. Allocate intermediate buffer for block.
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	620 i = get_bits(bd, 8);
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	621 if (i<'1' \|\| i>'9') return RETVAL_NOT_BZIP_DATA;
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	622 bd->dbufSize = 100000(i-'0')THREADS;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	623 for (i=0; i<THREADS; i++)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	624 bd->bwdata[i].dbuf = xmalloc(bd->dbufSize * sizeof(int));
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	625
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	626 return 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	627 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	628
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	629 // Example usage: decompress src_fd to dst_fd. (Stops at end of bzip data,
00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	630 // not end of file.)
64 67ee3a0b76e1 In bunzip replace setjmp/longjmp handling with error_exit(), replace string Rob Landley <rob@landley.net> parents: 62 diff changeset	631 void bunzipStream(int src_fd, int dst_fd)
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	632 {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	633 struct bunzip_data *bd;
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	634 int i, j;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	635
39 00e73c4dea66 More whitespace/cowbell. (And change comment style to //.) Rob Landley <rob@landley.net> parents: 37 diff changeset	636 if (!(i = start_bunzip(&bd,src_fd,0,0))) {
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	637 i = write_bunzip_data(bd,bd->bwdata,dst_fd,0,0);
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	638 if (i==RETVAL_LAST_BLOCK && bd->bwdata[0].headerCRC==bd->totalCRC)
34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	639 i = 0;
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	640 }
14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	641 flush_bunzip_outbuf(bd,dst_fd);
215 34e36dffd47a Major refactoring of bunzip.c in preparation for doing a multi-threaded version. Rob Landley <rob@landley.net> parents: 156 diff changeset	642 for (j=0; j<THREADS; j++) free(bd->bwdata[j].dbuf);
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	643 free(bd);
64 67ee3a0b76e1 In bunzip replace setjmp/longjmp handling with error_exit(), replace string Rob Landley <rob@landley.net> parents: 62 diff changeset	644 if (i) error_exit(bunzip_errors[-i]);
37 14d27eab3acf Add my old micro-bunzip library. Needs some cleanup... Rob Landley <rob@landley.net> parents: diff changeset	645 }

Mercurial > hg > toybox

annotate lib/bunzip.c @ 387:67b0ded3c56c