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diff --git a/i/pc104/initrd/conf/busybox/archival/libunarchive/decompress_bunzip2.c b/i/pc104/initrd/conf/busybox/archival/libunarchive/decompress_bunzip2.c
new file mode 100644
index 0000000..ff7d64d
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+++ b/i/pc104/initrd/conf/busybox/archival/libunarchive/decompress_bunzip2.c
@@ -0,0 +1,731 @@
+/* vi: set sw=4 ts=4: */
+/* Small bzip2 deflate implementation, by Rob Landley (rob@landley.net).
+
+ Based on bzip2 decompression code by Julian R Seward (jseward@acm.org),
+ which also acknowledges contributions by Mike Burrows, David Wheeler,
+ Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten,
+ Robert Sedgewick, and Jon L. Bentley.
+
+ Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+*/
+
+/*
+ Size and speed optimizations by Manuel Novoa III (mjn3@codepoet.org).
+
+ More efficient reading of Huffman codes, a streamlined read_bunzip()
+ function, and various other tweaks. In (limited) tests, approximately
+ 20% faster than bzcat on x86 and about 10% faster on arm.
+
+ Note that about 2/3 of the time is spent in read_unzip() reversing
+ the Burrows-Wheeler transformation. Much of that time is delay
+ resulting from cache misses.
+
+ I would ask that anyone benefiting from this work, especially those
+ using it in commercial products, consider making a donation to my local
+ non-profit hospice organization (www.hospiceacadiana.com) in the name of
+ the woman I loved, Toni W. Hagan, who passed away Feb. 12, 2003.
+
+ Manuel
+ */
+
+#include "libbb.h"
+#include "unarchive.h"
+
+/* Constants for Huffman coding */
+#define MAX_GROUPS 6
+#define GROUP_SIZE 50 /* 64 would have been more efficient */
+#define MAX_HUFCODE_BITS 20 /* Longest Huffman code allowed */
+#define MAX_SYMBOLS 258 /* 256 literals + RUNA + RUNB */
+#define SYMBOL_RUNA 0
+#define SYMBOL_RUNB 1
+
+/* Status return values */
+#define RETVAL_OK 0
+#define RETVAL_LAST_BLOCK (-1)
+#define RETVAL_NOT_BZIP_DATA (-2)
+#define RETVAL_UNEXPECTED_INPUT_EOF (-3)
+#define RETVAL_UNEXPECTED_OUTPUT_EOF (-4)
+#define RETVAL_DATA_ERROR (-5)
+#define RETVAL_OUT_OF_MEMORY (-6)
+#define RETVAL_OBSOLETE_INPUT (-7)
+
+/* Other housekeeping constants */
+#define IOBUF_SIZE 4096
+
+/* This is what we know about each Huffman coding group */
+struct group_data {
+ /* We have an extra slot at the end of limit[] for a sentinal value. */
+ int limit[MAX_HUFCODE_BITS+1],base[MAX_HUFCODE_BITS],permute[MAX_SYMBOLS];
+ int minLen, maxLen;
+};
+
+/* Structure holding all the housekeeping data, including IO buffers and
+ memory that persists between calls to bunzip */
+
+typedef struct {
+ /* State for interrupting output loop */
+
+ int writeCopies,writePos,writeRunCountdown,writeCount,writeCurrent;
+
+ /* I/O tracking data (file handles, buffers, positions, etc.) */
+
+ int in_fd,out_fd,inbufCount,inbufPos /*,outbufPos*/;
+ unsigned char *inbuf /*,*outbuf*/;
+ unsigned int inbufBitCount, inbufBits;
+
+ /* The CRC values stored in the block header and calculated from the data */
+
+ uint32_t headerCRC, totalCRC, writeCRC;
+ uint32_t *crc32Table;
+ /* Intermediate buffer and its size (in bytes) */
+
+ unsigned int *dbuf, dbufSize;
+
+ /* These things are a bit too big to go on the stack */
+
+ unsigned char selectors[32768]; /* nSelectors=15 bits */
+ struct group_data groups[MAX_GROUPS]; /* Huffman coding tables */
+
+ /* For I/O error handling */
+
+ jmp_buf jmpbuf;
+} bunzip_data;
+
+/* Return the next nnn bits of input. All reads from the compressed input
+ are done through this function. All reads are big endian */
+
+static unsigned int get_bits(bunzip_data *bd, char bits_wanted)
+{
+ unsigned int bits=0;
+
+ /* If we need to get more data from the byte buffer, do so. (Loop getting
+ one byte at a time to enforce endianness and avoid unaligned access.) */
+
+ while (bd->inbufBitCount<bits_wanted) {
+
+ /* If we need to read more data from file into byte buffer, do so */
+
+ if(bd->inbufPos==bd->inbufCount) {
+ if((bd->inbufCount = read(bd->in_fd, bd->inbuf, IOBUF_SIZE)) <= 0)
+ longjmp(bd->jmpbuf,RETVAL_UNEXPECTED_INPUT_EOF);
+ bd->inbufPos=0;
+ }
+
+ /* Avoid 32-bit overflow (dump bit buffer to top of output) */
+
+ if(bd->inbufBitCount>=24) {
+ bits=bd->inbufBits&((1<<bd->inbufBitCount)-1);
+ bits_wanted-=bd->inbufBitCount;
+ bits<<=bits_wanted;
+ bd->inbufBitCount=0;
+ }
+
+ /* Grab next 8 bits of input from buffer. */
+
+ bd->inbufBits=(bd->inbufBits<<8)|bd->inbuf[bd->inbufPos++];
+ bd->inbufBitCount+=8;
+ }
+
+ /* Calculate result */
+
+ bd->inbufBitCount-=bits_wanted;
+ bits|=(bd->inbufBits>>bd->inbufBitCount)&((1<<bits_wanted)-1);
+
+ return bits;
+}
+
+/* Unpacks the next block and sets up for the inverse burrows-wheeler step. */
+
+static int get_next_block(bunzip_data *bd)
+{
+ struct group_data *hufGroup;
+ int dbufCount,nextSym,dbufSize,groupCount,*base,*limit,selector,
+ i,j,k,t,runPos,symCount,symTotal,nSelectors,byteCount[256];
+ unsigned char uc, symToByte[256], mtfSymbol[256], *selectors;
+ unsigned int *dbuf,origPtr;
+
+ dbuf=bd->dbuf;
+ dbufSize=bd->dbufSize;
+ selectors=bd->selectors;
+
+ /* Reset longjmp I/O error handling */
+
+ i=setjmp(bd->jmpbuf);
+ if (i) return i;
+
+ /* Read in header signature and CRC, then validate signature.
+ (last block signature means CRC is for whole file, return now) */
+
+ i = get_bits(bd,24);
+ j = get_bits(bd,24);
+ bd->headerCRC=get_bits(bd,32);
+ if ((i == 0x177245) && (j == 0x385090)) return RETVAL_LAST_BLOCK;
+ if ((i != 0x314159) || (j != 0x265359)) return RETVAL_NOT_BZIP_DATA;
+
+ /* We can add support for blockRandomised if anybody complains. There was
+ some code for this in busybox 1.0.0-pre3, but nobody ever noticed that
+ it didn't actually work. */
+
+ if (get_bits(bd,1)) return RETVAL_OBSOLETE_INPUT;
+ if ((origPtr=get_bits(bd,24)) > dbufSize) return RETVAL_DATA_ERROR;
+
+ /* mapping table: if some byte values are never used (encoding things
+ like ascii text), the compression code removes the gaps to have fewer
+ symbols to deal with, and writes a sparse bitfield indicating which
+ values were present. We make a translation table to convert the symbols
+ back to the corresponding bytes. */
+
+ t=get_bits(bd, 16);
+ symTotal=0;
+ for (i=0;i<16;i++) {
+ if(t&(1<<(15-i))) {
+ k=get_bits(bd,16);
+ for (j=0;j<16;j++)
+ if(k&(1<<(15-j))) symToByte[symTotal++]=(16*i)+j;
+ }
+ }
+
+ /* How many different Huffman coding groups does this block use? */
+
+ groupCount=get_bits(bd,3);
+ if (groupCount<2 || groupCount>MAX_GROUPS) return RETVAL_DATA_ERROR;
+
+ /* nSelectors: Every GROUP_SIZE many symbols we select a new Huffman coding
+ group. Read in the group selector list, which is stored as MTF encoded
+ bit runs. (MTF=Move To Front, as each value is used it's moved to the
+ start of the list.) */
+
+ if(!(nSelectors=get_bits(bd, 15))) return RETVAL_DATA_ERROR;
+ for (i=0; i<groupCount; i++) mtfSymbol[i] = i;
+ for (i=0; i<nSelectors; i++) {
+
+ /* Get next value */
+
+ for (j=0;get_bits(bd,1);j++) if (j>=groupCount) return RETVAL_DATA_ERROR;
+
+ /* Decode MTF to get the next selector */
+
+ uc = mtfSymbol[j];
+ for (;j;j--) mtfSymbol[j] = mtfSymbol[j-1];
+ mtfSymbol[0]=selectors[i]=uc;
+ }
+
+ /* Read the Huffman coding tables for each group, which code for symTotal
+ literal symbols, plus two run symbols (RUNA, RUNB) */
+
+ symCount=symTotal+2;
+ for (j=0; j<groupCount; j++) {
+ unsigned char length[MAX_SYMBOLS],temp[MAX_HUFCODE_BITS+1];
+ int minLen, maxLen, pp;
+
+ /* Read Huffman code lengths for each symbol. They're stored in
+ a way similar to mtf; record a starting value for the first symbol,
+ and an offset from the previous value for everys symbol after that.
+ (Subtracting 1 before the loop and then adding it back at the end is
+ an optimization that makes the test inside the loop simpler: symbol
+ length 0 becomes negative, so an unsigned inequality catches it.) */
+
+ t=get_bits(bd, 5)-1;
+ for (i = 0; i < symCount; i++) {
+ for (;;) {
+ if (((unsigned)t) > (MAX_HUFCODE_BITS-1))
+ return RETVAL_DATA_ERROR;
+
+ /* If first bit is 0, stop. Else second bit indicates whether
+ to increment or decrement the value. Optimization: grab 2
+ bits and unget the second if the first was 0. */
+
+ k = get_bits(bd,2);
+ if (k < 2) {
+ bd->inbufBitCount++;
+ break;
+ }
+
+ /* Add one if second bit 1, else subtract 1. Avoids if/else */
+
+ t+=(((k+1)&2)-1);
+ }
+
+ /* Correct for the initial -1, to get the final symbol length */
+
+ length[i]=t+1;
+ }
+
+ /* Find largest and smallest lengths in this group */
+
+ minLen=maxLen=length[0];
+ for (i = 1; i < symCount; i++) {
+ if(length[i] > maxLen) maxLen = length[i];
+ else if(length[i] < minLen) minLen = length[i];
+ }
+
+ /* Calculate permute[], base[], and limit[] tables from length[].
+ *
+ * permute[] is the lookup table for converting Huffman coded symbols
+ * into decoded symbols. base[] is the amount to subtract from the
+ * value of a Huffman symbol of a given length when using permute[].
+ *
+ * limit[] indicates the largest numerical value a symbol with a given
+ * number of bits can have. This is how the Huffman codes can vary in
+ * length: each code with a value>limit[length] needs another bit.
+ */
+
+ hufGroup=bd->groups+j;
+ hufGroup->minLen = minLen;
+ hufGroup->maxLen = maxLen;
+
+ /* Note that minLen can't be smaller than 1, so we adjust the base
+ and limit array pointers so we're not always wasting the first
+ entry. We do this again when using them (during symbol decoding).*/
+
+ base=hufGroup->base-1;
+ limit=hufGroup->limit-1;
+
+ /* Calculate permute[]. Concurently, initialize temp[] and limit[]. */
+
+ pp=0;
+ for (i=minLen;i<=maxLen;i++) {
+ temp[i]=limit[i]=0;
+ for (t=0;t<symCount;t++)
+ if(length[t]==i) hufGroup->permute[pp++] = t;
+ }
+
+ /* Count symbols coded for at each bit length */
+
+ for (i=0;i<symCount;i++) temp[length[i]]++;
+
+ /* Calculate limit[] (the largest symbol-coding value at each bit
+ * length, which is (previous limit<<1)+symbols at this level), and
+ * base[] (number of symbols to ignore at each bit length, which is
+ * limit minus the cumulative count of symbols coded for already). */
+
+ pp=t=0;
+ for (i=minLen; i<maxLen; i++) {
+ pp+=temp[i];
+
+ /* We read the largest possible symbol size and then unget bits
+ after determining how many we need, and those extra bits could
+ be set to anything. (They're noise from future symbols.) At
+ each level we're really only interested in the first few bits,
+ so here we set all the trailing to-be-ignored bits to 1 so they
+ don't affect the value>limit[length] comparison. */
+
+ limit[i]= (pp << (maxLen - i)) - 1;
+ pp<<=1;
+ base[i+1]=pp-(t+=temp[i]);
+ }
+ limit[maxLen+1] = INT_MAX; /* Sentinal value for reading next sym. */
+ limit[maxLen]=pp+temp[maxLen]-1;
+ base[minLen]=0;
+ }
+
+ /* We've finished reading and digesting the block header. Now read this
+ block's Huffman coded symbols from the file and undo the Huffman coding
+ and run length encoding, saving the result into dbuf[dbufCount++]=uc */
+
+ /* Initialize symbol occurrence counters and symbol Move To Front table */
+
+ for (i=0;i<256;i++) {
+ byteCount[i] = 0;
+ mtfSymbol[i]=(unsigned char)i;
+ }
+
+ /* Loop through compressed symbols. */
+
+ runPos=dbufCount=selector=0;
+ for (;;) {
+
+ /* fetch next Huffman coding group from list. */
+
+ symCount=GROUP_SIZE-1;
+ if(selector>=nSelectors) return RETVAL_DATA_ERROR;
+ hufGroup=bd->groups+selectors[selector++];
+ base=hufGroup->base-1;
+ limit=hufGroup->limit-1;
+continue_this_group:
+
+ /* Read next Huffman-coded symbol. */
+
+ /* Note: It is far cheaper to read maxLen bits and back up than it is
+ to read minLen bits and then an additional bit at a time, testing
+ as we go. Because there is a trailing last block (with file CRC),
+ there is no danger of the overread causing an unexpected EOF for a
+ valid compressed file. As a further optimization, we do the read
+ inline (falling back to a call to get_bits if the buffer runs
+ dry). The following (up to got_huff_bits:) is equivalent to
+ j=get_bits(bd,hufGroup->maxLen);
+ */
+
+ while (bd->inbufBitCount<hufGroup->maxLen) {
+ if(bd->inbufPos==bd->inbufCount) {
+ j = get_bits(bd,hufGroup->maxLen);
+ goto got_huff_bits;
+ }
+ bd->inbufBits=(bd->inbufBits<<8)|bd->inbuf[bd->inbufPos++];
+ bd->inbufBitCount+=8;
+ };
+ bd->inbufBitCount-=hufGroup->maxLen;
+ j = (bd->inbufBits>>bd->inbufBitCount)&((1<<hufGroup->maxLen)-1);
+
+got_huff_bits:
+
+ /* Figure how how many bits are in next symbol and unget extras */
+
+ i=hufGroup->minLen;
+ while (j>limit[i]) ++i;
+ bd->inbufBitCount += (hufGroup->maxLen - i);
+
+ /* Huffman decode value to get nextSym (with bounds checking) */
+
+ if ((i > hufGroup->maxLen)
+ || (((unsigned)(j=(j>>(hufGroup->maxLen-i))-base[i]))
+ >= MAX_SYMBOLS))
+ return RETVAL_DATA_ERROR;
+ nextSym = hufGroup->permute[j];
+
+ /* We have now decoded the symbol, which indicates either a new literal
+ byte, or a repeated run of the most recent literal byte. First,
+ check if nextSym indicates a repeated run, and if so loop collecting
+ how many times to repeat the last literal. */
+
+ if (((unsigned)nextSym) <= SYMBOL_RUNB) { /* RUNA or RUNB */
+
+ /* If this is the start of a new run, zero out counter */
+
+ if(!runPos) {
+ runPos = 1;
+ t = 0;
+ }
+
+ /* Neat trick that saves 1 symbol: instead of or-ing 0 or 1 at
+ each bit position, add 1 or 2 instead. For example,
+ 1011 is 1<<0 + 1<<1 + 2<<2. 1010 is 2<<0 + 2<<1 + 1<<2.
+ You can make any bit pattern that way using 1 less symbol than
+ the basic or 0/1 method (except all bits 0, which would use no
+ symbols, but a run of length 0 doesn't mean anything in this
+ context). Thus space is saved. */
+
+ t += (runPos << nextSym); /* +runPos if RUNA; +2*runPos if RUNB */
+ if(runPos < dbufSize) runPos <<= 1;
+ goto end_of_huffman_loop;
+ }
+
+ /* When we hit the first non-run symbol after a run, we now know
+ how many times to repeat the last literal, so append that many
+ copies to our buffer of decoded symbols (dbuf) now. (The last
+ literal used is the one at the head of the mtfSymbol array.) */
+
+ if(runPos) {
+ runPos=0;
+ if(dbufCount+t>=dbufSize) return RETVAL_DATA_ERROR;
+
+ uc = symToByte[mtfSymbol[0]];
+ byteCount[uc] += t;
+ while (t--) dbuf[dbufCount++]=uc;
+ }
+
+ /* Is this the terminating symbol? */
+
+ if(nextSym>symTotal) break;
+
+ /* At this point, nextSym indicates a new literal character. Subtract
+ one to get the position in the MTF array at which this literal is
+ currently to be found. (Note that the result can't be -1 or 0,
+ because 0 and 1 are RUNA and RUNB. But another instance of the
+ first symbol in the mtf array, position 0, would have been handled
+ as part of a run above. Therefore 1 unused mtf position minus
+ 2 non-literal nextSym values equals -1.) */
+
+ if(dbufCount>=dbufSize) return RETVAL_DATA_ERROR;
+ i = nextSym - 1;
+ uc = mtfSymbol[i];
+
+ /* Adjust the MTF array. Since we typically expect to move only a
+ * small number of symbols, and are bound by 256 in any case, using
+ * memmove here would typically be bigger and slower due to function
+ * call overhead and other assorted setup costs. */
+
+ do {
+ mtfSymbol[i] = mtfSymbol[i-1];
+ } while (--i);
+ mtfSymbol[0] = uc;
+ uc=symToByte[uc];
+
+ /* We have our literal byte. Save it into dbuf. */
+
+ byteCount[uc]++;
+ dbuf[dbufCount++] = (unsigned int)uc;
+
+ /* Skip group initialization if we're not done with this group. Done
+ * this way to avoid compiler warning. */
+
+end_of_huffman_loop:
+ if(symCount--) goto continue_this_group;
+ }
+
+ /* At this point, we've read all the Huffman-coded symbols (and repeated
+ runs) for this block from the input stream, and decoded them into the
+ intermediate buffer. There are dbufCount many decoded bytes in dbuf[].
+ Now undo the Burrows-Wheeler transform on dbuf.
+ See http://dogma.net/markn/articles/bwt/bwt.htm
+ */
+
+ /* Turn byteCount into cumulative occurrence counts of 0 to n-1. */
+
+ j=0;
+ for (i=0;i<256;i++) {
+ k=j+byteCount[i];
+ byteCount[i] = j;
+ j=k;
+ }
+
+ /* Figure out what order dbuf would be in if we sorted it. */
+
+ for (i=0;i<dbufCount;i++) {
+ uc=(unsigned char)(dbuf[i] & 0xff);
+ dbuf[byteCount[uc]] |= (i << 8);
+ byteCount[uc]++;
+ }
+
+ /* Decode first byte by hand to initialize "previous" byte. Note that it
+ doesn't get output, and if the first three characters are identical
+ it doesn't qualify as a run (hence writeRunCountdown=5). */
+
+ if(dbufCount) {
+ if(origPtr>=dbufCount) return RETVAL_DATA_ERROR;
+ bd->writePos=dbuf[origPtr];
+ bd->writeCurrent=(unsigned char)(bd->writePos&0xff);
+ bd->writePos>>=8;
+ bd->writeRunCountdown=5;
+ }
+ bd->writeCount=dbufCount;
+
+ return RETVAL_OK;
+}
+
+/* Undo burrows-wheeler transform on intermediate buffer to produce output.
+ If start_bunzip was initialized with out_fd=-1, then up to len bytes of
+ data are written to outbuf. Return value is number of bytes written or
+ error (all errors are negative numbers). If out_fd!=-1, outbuf and len
+ are ignored, data is written to out_fd and return is RETVAL_OK or error.
+*/
+
+static int read_bunzip(bunzip_data *bd, char *outbuf, int len)
+{
+ const unsigned int *dbuf;
+ int pos,current,previous,gotcount;
+
+ /* If last read was short due to end of file, return last block now */
+ if(bd->writeCount<0) return bd->writeCount;
+
+ gotcount = 0;
+ dbuf=bd->dbuf;
+ pos=bd->writePos;
+ current=bd->writeCurrent;
+
+ /* We will always have pending decoded data to write into the output
+ buffer unless this is the very first call (in which case we haven't
+ Huffman-decoded a block into the intermediate buffer yet). */
+
+ if (bd->writeCopies) {
+
+ /* Inside the loop, writeCopies means extra copies (beyond 1) */
+
+ --bd->writeCopies;
+
+ /* Loop outputting bytes */
+
+ for (;;) {
+
+ /* If the output buffer is full, snapshot state and return */
+
+ if(gotcount >= len) {
+ bd->writePos=pos;
+ bd->writeCurrent=current;
+ bd->writeCopies++;
+ return len;
+ }
+
+ /* Write next byte into output buffer, updating CRC */
+
+ outbuf[gotcount++] = current;
+ bd->writeCRC=(((bd->writeCRC)<<8)
+ ^bd->crc32Table[((bd->writeCRC)>>24)^current]);
+
+ /* Loop now if we're outputting multiple copies of this byte */
+
+ if (bd->writeCopies) {
+ --bd->writeCopies;
+ continue;
+ }
+decode_next_byte:
+ if (!bd->writeCount--) break;
+ /* Follow sequence vector to undo Burrows-Wheeler transform */
+ previous=current;
+ pos=dbuf[pos];
+ current=pos&0xff;
+ pos>>=8;
+
+ /* After 3 consecutive copies of the same byte, the 4th is a repeat
+ count. We count down from 4 instead
+ * of counting up because testing for non-zero is faster */
+
+ if(--bd->writeRunCountdown) {
+ if(current!=previous) bd->writeRunCountdown=4;
+ } else {
+
+ /* We have a repeated run, this byte indicates the count */
+
+ bd->writeCopies=current;
+ current=previous;
+ bd->writeRunCountdown=5;
+
+ /* Sometimes there are just 3 bytes (run length 0) */
+
+ if(!bd->writeCopies) goto decode_next_byte;
+
+ /* Subtract the 1 copy we'd output anyway to get extras */
+
+ --bd->writeCopies;
+ }
+ }
+
+ /* Decompression of this block completed successfully */
+
+ bd->writeCRC=~bd->writeCRC;
+ bd->totalCRC=((bd->totalCRC<<1) | (bd->totalCRC>>31)) ^ bd->writeCRC;
+
+ /* If this block had a CRC error, force file level CRC error. */
+
+ if(bd->writeCRC!=bd->headerCRC) {
+ bd->totalCRC=bd->headerCRC+1;
+ return RETVAL_LAST_BLOCK;
+ }
+ }
+
+ /* Refill the intermediate buffer by Huffman-decoding next block of input */
+ /* (previous is just a convenient unused temp variable here) */
+
+ previous=get_next_block(bd);
+ if(previous) {
+ bd->writeCount=previous;
+ return (previous!=RETVAL_LAST_BLOCK) ? previous : gotcount;
+ }
+ bd->writeCRC=~0;
+ pos=bd->writePos;
+ current=bd->writeCurrent;
+ goto decode_next_byte;
+}
+
+/* Allocate the structure, read file header. If in_fd==-1, inbuf must contain
+ a complete bunzip file (len bytes long). If in_fd!=-1, inbuf and len are
+ ignored, and data is read from file handle into temporary buffer. */
+
+static int start_bunzip(bunzip_data **bdp, int in_fd, unsigned char *inbuf,
+ int len)
+{
+ bunzip_data *bd;
+ unsigned int i;
+ const unsigned int BZh0=(((unsigned int)'B')<<24)+(((unsigned int)'Z')<<16)
+ +(((unsigned int)'h')<<8)+(unsigned int)'0';
+
+ /* Figure out how much data to allocate */
+
+ i=sizeof(bunzip_data);
+ if(in_fd!=-1) i+=IOBUF_SIZE;
+
+ /* Allocate bunzip_data. Most fields initialize to zero. */
+
+ bd=*bdp=xzalloc(i);
+
+ /* Setup input buffer */
+
+ if(-1==(bd->in_fd=in_fd)) {
+ bd->inbuf=inbuf;
+ bd->inbufCount=len;
+ } else bd->inbuf=(unsigned char *)(bd+1);
+
+ /* Init the CRC32 table (big endian) */
+
+ bd->crc32Table = crc32_filltable(1);
+
+ /* Setup for I/O error handling via longjmp */
+
+ i=setjmp(bd->jmpbuf);
+ if(i) return i;
+
+ /* Ensure that file starts with "BZh['1'-'9']." */
+
+ i = get_bits(bd,32);
+ if (((unsigned int)(i-BZh0-1)) >= 9) return RETVAL_NOT_BZIP_DATA;
+
+ /* Fourth byte (ascii '1'-'9'), indicates block size in units of 100k of
+ uncompressed data. Allocate intermediate buffer for block. */
+
+ bd->dbufSize=100000*(i-BZh0);
+
+ bd->dbuf=xmalloc(bd->dbufSize * sizeof(int));
+ return RETVAL_OK;
+}
+
+/* Example usage: decompress src_fd to dst_fd. (Stops at end of bzip data,
+ not end of file.) */
+
+USE_DESKTOP(long long) int
+uncompressStream(int src_fd, int dst_fd)
+{
+ USE_DESKTOP(long long total_written = 0;)
+ char *outbuf;
+ bunzip_data *bd;
+ int i;
+
+ outbuf=xmalloc(IOBUF_SIZE);
+ i=start_bunzip(&bd,src_fd,0,0);
+ if(!i) {
+ for (;;) {
+ if((i=read_bunzip(bd,outbuf,IOBUF_SIZE)) <= 0) break;
+ if(i!=write(dst_fd,outbuf,i)) {
+ i=RETVAL_UNEXPECTED_OUTPUT_EOF;
+ break;
+ }
+ USE_DESKTOP(total_written += i;)
+ }
+ }
+
+ /* Check CRC and release memory */
+
+ if(i==RETVAL_LAST_BLOCK) {
+ if (bd->headerCRC!=bd->totalCRC) {
+ bb_error_msg("data integrity error when decompressing");
+ } else {
+ i=RETVAL_OK;
+ }
+ } else if (i==RETVAL_UNEXPECTED_OUTPUT_EOF) {
+ bb_error_msg("compressed file ends unexpectedly");
+ } else {
+ bb_error_msg("decompression failed");
+ }
+ free(bd->dbuf);
+ free(bd);
+ free(outbuf);
+
+ return i ? i : USE_DESKTOP(total_written) + 0;
+}
+
+#ifdef TESTING
+
+static char * const bunzip_errors[]={NULL,"Bad file checksum","Not bzip data",
+ "Unexpected input EOF","Unexpected output EOF","Data error",
+ "Out of memory","Obsolete (pre 0.9.5) bzip format not supported."};
+
+/* Dumb little test thing, decompress stdin to stdout */
+int main(int argc, char *argv[])
+{
+ int i=uncompressStream(0,1);
+ char c;
+
+ if(i<0) fprintf(stderr,"%s\n", bunzip_errors[-i]);
+ else if(read(0,&c,1)) fprintf(stderr,"Trailing garbage ignored\n");
+ return -i;
+}
+#endif