bunzip2: big style cleanup. No code changes apart from one s/write/safe_write/

(verified with objdump).
This commit is contained in:
Denis Vlasenko 2007-04-10 17:16:33 +00:00
parent a9d7d24e1f
commit b38cf3ff8a

View File

@ -55,7 +55,7 @@
/* 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 limit[MAX_HUFCODE_BITS+1], base[MAX_HUFCODE_BITS], permute[MAX_SYMBOLS];
int minLen, maxLen;
};
@ -65,13 +65,13 @@ struct group_data {
typedef struct {
/* State for interrupting output loop */
int writeCopies,writePos,writeRunCountdown,writeCount,writeCurrent;
int writeCopies, writePos, writeRunCountdown, writeCount, writeCurrent;
/* I/O tracking data (file handles, buffers, positions, etc.) */
int in_fd,out_fd,inbufCount,inbufPos /*,outbufPos*/;
int in_fd, out_fd, inbufCount, inbufPos /*, outbufPos*/;
unsigned char *inbuf /*,*outbuf*/;
unsigned int inbufBitCount, inbufBits;
unsigned inbufBitCount, inbufBits;
/* The CRC values stored in the block header and calculated from the data */
@ -79,7 +79,7 @@ typedef struct {
uint32_t *crc32Table;
/* Intermediate buffer and its size (in bytes) */
unsigned int *dbuf, dbufSize;
unsigned *dbuf, dbufSize;
/* These things are a bit too big to go on the stack */
@ -94,42 +94,43 @@ typedef struct {
/* 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)
static unsigned get_bits(bunzip_data *bd, char bits_wanted)
{
unsigned int bits=0;
unsigned 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) {
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;
if (bd->inbufPos == bd->inbufCount) {
bd->inbufCount = read(bd->in_fd, bd->inbuf, IOBUF_SIZE);
if (bd->inbufCount <= 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;
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;
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);
bd->inbufBitCount -= bits_wanted;
bits |= (bd->inbufBits >> bd->inbufBitCount) & ((1 << bits_wanted) - 1);
return bits;
}
@ -139,26 +140,26 @@ static unsigned int get_bits(bunzip_data *bd, char bits_wanted)
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];
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;
unsigned *dbuf, origPtr;
dbuf=bd->dbuf;
dbufSize=bd->dbufSize;
selectors=bd->selectors;
dbuf = bd->dbuf;
dbufSize = bd->dbufSize;
selectors = bd->selectors;
/* Reset longjmp I/O error handling */
i=setjmp(bd->jmpbuf);
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);
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;
@ -166,8 +167,9 @@ static int get_next_block(bunzip_data *bd)
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;
if (get_bits(bd, 1)) return RETVAL_OBSOLETE_INPUT;
origPtr = get_bits(bd, 24);
if (origPtr > 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
@ -175,48 +177,52 @@ static int get_next_block(bunzip_data *bd)
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;
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;
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++) {
nSelectors = get_bits(bd, 15);
if (!nSelectors) 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;
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;
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;
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,
@ -225,17 +231,17 @@ static int get_next_block(bunzip_data *bd)
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;
t = get_bits(bd, 5) - 1;
for (i = 0; i < symCount; i++) {
for (;;) {
if (((unsigned)t) > (MAX_HUFCODE_BITS-1))
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);
k = get_bits(bd, 2);
if (k < 2) {
bd->inbufBitCount++;
break;
@ -243,20 +249,20 @@ static int get_next_block(bunzip_data *bd)
/* Add one if second bit 1, else subtract 1. Avoids if/else */
t+=(((k+1)&2)-1);
t += (((k+1) & 2) - 1);
}
/* Correct for the initial -1, to get the final symbol length */
length[i]=t+1;
length[i] = t + 1;
}
/* Find largest and smallest lengths in this group */
minLen=maxLen=length[0];
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];
if (length[i] > maxLen) maxLen = length[i];
else if (length[i] < minLen) minLen = length[i];
}
/* Calculate permute[], base[], and limit[] tables from length[].
@ -270,7 +276,7 @@ static int get_next_block(bunzip_data *bd)
* length: each code with a value>limit[length] needs another bit.
*/
hufGroup=bd->groups+j;
hufGroup = bd->groups + j;
hufGroup->minLen = minLen;
hufGroup->maxLen = maxLen;
@ -278,30 +284,31 @@ static int get_next_block(bunzip_data *bd)
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;
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;
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]]++;
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];
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
@ -310,13 +317,14 @@ static int get_next_block(bunzip_data *bd)
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[i] = (pp << (maxLen - i)) - 1;
pp <<= 1;
t += temp[i];
base[i+1] = pp - t;
}
limit[maxLen+1] = INT_MAX; /* Sentinal value for reading next sym. */
limit[maxLen]=pp+temp[maxLen]-1;
base[minLen]=0;
limit[maxLen] = pp + temp[maxLen] - 1;
base[minLen] = 0;
}
/* We've finished reading and digesting the block header. Now read this
@ -325,24 +333,24 @@ static int get_next_block(bunzip_data *bd)
/* Initialize symbol occurrence counters and symbol Move To Front table */
for (i=0;i<256;i++) {
for (i = 0; i < 256; i++) {
byteCount[i] = 0;
mtfSymbol[i]=(unsigned char)i;
mtfSymbol[i] = (unsigned char)i;
}
/* Loop through compressed symbols. */
runPos=dbufCount=selector=0;
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:
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. */
@ -353,33 +361,34 @@ continue_this_group:
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);
j = get_bits(bd, hufGroup->maxLen);
*/
while (bd->inbufBitCount<hufGroup->maxLen) {
if(bd->inbufPos==bd->inbufCount) {
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->inbufBits = (bd->inbufBits << 8) | bd->inbuf[bd->inbufPos++];
bd->inbufBitCount += 8;
};
bd->inbufBitCount-=hufGroup->maxLen;
j = (bd->inbufBits>>bd->inbufBitCount)&((1<<hufGroup->maxLen)-1);
bd->inbufBitCount -= hufGroup->maxLen;
j = (bd->inbufBits >> bd->inbufBitCount) & ((1 << hufGroup->maxLen) - 1);
got_huff_bits:
got_huff_bits:
/* Figure how how many bits are in next symbol and unget extras */
i=hufGroup->minLen;
while (j>limit[i]) ++i;
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))
if (i > hufGroup->maxLen)
return RETVAL_DATA_ERROR;
j = (j >> (hufGroup->maxLen - i)) - base[i];
if ((unsigned)j >= MAX_SYMBOLS)
return RETVAL_DATA_ERROR;
nextSym = hufGroup->permute[j];
@ -388,11 +397,11 @@ got_huff_bits:
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 ((unsigned)nextSym <= SYMBOL_RUNB) { /* RUNA or RUNB */
/* If this is the start of a new run, zero out counter */
if(!runPos) {
if (!runPos) {
runPos = 1;
t = 0;
}
@ -406,7 +415,7 @@ got_huff_bits:
context). Thus space is saved. */
t += (runPos << nextSym); /* +runPos if RUNA; +2*runPos if RUNB */
if(runPos < dbufSize) runPos <<= 1;
if (runPos < dbufSize) runPos <<= 1;
goto end_of_huffman_loop;
}
@ -415,18 +424,18 @@ got_huff_bits:
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;
if (runPos) {
runPos = 0;
if (dbufCount + t >= dbufSize) return RETVAL_DATA_ERROR;
uc = symToByte[mtfSymbol[0]];
byteCount[uc] += t;
while (t--) dbuf[dbufCount++]=uc;
while (t--) dbuf[dbufCount++] = uc;
}
/* Is this the terminating symbol? */
if(nextSym>symTotal) break;
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
@ -436,7 +445,7 @@ got_huff_bits:
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;
if (dbufCount >= dbufSize) return RETVAL_DATA_ERROR;
i = nextSym - 1;
uc = mtfSymbol[i];
@ -449,18 +458,18 @@ got_huff_bits:
mtfSymbol[i] = mtfSymbol[i-1];
} while (--i);
mtfSymbol[0] = uc;
uc=symToByte[uc];
uc = symToByte[uc];
/* We have our literal byte. Save it into dbuf. */
byteCount[uc]++;
dbuf[dbufCount++] = (unsigned int)uc;
dbuf[dbufCount++] = (unsigned)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;
end_of_huffman_loop:
if (symCount--) goto continue_this_group;
}
/* At this point, we've read all the Huffman-coded symbols (and repeated
@ -472,17 +481,17 @@ end_of_huffman_loop:
/* Turn byteCount into cumulative occurrence counts of 0 to n-1. */
j=0;
for (i=0;i<256;i++) {
k=j+byteCount[i];
j = 0;
for (i = 0; i < 256; i++) {
k = j + byteCount[i];
byteCount[i] = j;
j=k;
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);
for (i = 0; i < dbufCount; i++) {
uc = (unsigned char)(dbuf[i] & 0xff);
dbuf[byteCount[uc]] |= (i << 8);
byteCount[uc]++;
}
@ -491,14 +500,14 @@ end_of_huffman_loop:
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;
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;
bd->writeCount = dbufCount;
return RETVAL_OK;
}
@ -512,16 +521,16 @@ end_of_huffman_loop:
static int read_bunzip(bunzip_data *bd, char *outbuf, int len)
{
const unsigned int *dbuf;
int pos,current,previous,gotcount;
const unsigned *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;
if (bd->writeCount < 0) return bd->writeCount;
gotcount = 0;
dbuf=bd->dbuf;
pos=bd->writePos;
current=bd->writeCurrent;
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
@ -539,9 +548,9 @@ static int read_bunzip(bunzip_data *bd, char *outbuf, int len)
/* If the output buffer is full, snapshot state and return */
if(gotcount >= len) {
bd->writePos=pos;
bd->writeCurrent=current;
if (gotcount >= len) {
bd->writePos =pos;
bd->writeCurrent = current;
bd->writeCopies++;
return len;
}
@ -549,8 +558,8 @@ static int read_bunzip(bunzip_data *bd, char *outbuf, int len)
/* Write next byte into output buffer, updating CRC */
outbuf[gotcount++] = current;
bd->writeCRC=(((bd->writeCRC)<<8)
^bd->crc32Table[((bd->writeCRC)>>24)^current]);
bd->writeCRC = (bd->writeCRC << 8)
^ bd->crc32Table[(bd->writeCRC >> 24) ^ current];
/* Loop now if we're outputting multiple copies of this byte */
@ -558,31 +567,32 @@ static int read_bunzip(bunzip_data *bd, char *outbuf, int len)
--bd->writeCopies;
continue;
}
decode_next_byte:
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;
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;
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;
bd->writeCopies = current;
current = previous;
bd->writeRunCountdown = 5;
/* Sometimes there are just 3 bytes (run length 0) */
if(!bd->writeCopies) goto decode_next_byte;
if (!bd->writeCopies) goto decode_next_byte;
/* Subtract the 1 copy we'd output anyway to get extras */
@ -592,13 +602,13 @@ decode_next_byte:
/* Decompression of this block completed successfully */
bd->writeCRC=~bd->writeCRC;
bd->totalCRC=((bd->totalCRC<<1) | (bd->totalCRC>>31)) ^ bd->writeCRC;
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;
if (bd->writeCRC != bd->headerCRC) {
bd->totalCRC = bd->headerCRC+1;
return RETVAL_LAST_BLOCK;
}
}
@ -606,14 +616,14 @@ decode_next_byte:
/* 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;
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;
bd->writeCRC = ~0;
pos = bd->writePos;
current = bd->writeCurrent;
goto decode_next_byte;
}
@ -625,25 +635,28 @@ 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';
unsigned i;
enum {
BZh0 = ('B' << 24) + ('Z' << 16) + ('h' << 8) + '0'
};
/* Figure out how much data to allocate */
i=sizeof(bunzip_data);
if(in_fd!=-1) i+=IOBUF_SIZE;
i = sizeof(bunzip_data);
if (in_fd != -1) i += IOBUF_SIZE;
/* Allocate bunzip_data. Most fields initialize to zero. */
bd=*bdp=xzalloc(i);
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);
bd->in_fd = in_fd;
if (-1 == in_fd) {
bd->inbuf = inbuf;
bd->inbufCount = len;
} else
bd->inbuf = (unsigned char *)(bd + 1);
/* Init the CRC32 table (big endian) */
@ -651,20 +664,20 @@ static int start_bunzip(bunzip_data **bdp, int in_fd, unsigned char *inbuf,
/* Setup for I/O error handling via longjmp */
i=setjmp(bd->jmpbuf);
if(i) return i;
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;
i = get_bits(bd, 32);
if (((unsigned)(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->dbufSize = 100000 * (i - BZh0);
bd->dbuf=xmalloc(bd->dbufSize * sizeof(int));
bd->dbuf = xmalloc(bd->dbufSize * sizeof(int));
return RETVAL_OK;
}
@ -679,13 +692,14 @@ uncompressStream(int src_fd, int dst_fd)
bunzip_data *bd;
int i;
outbuf=xmalloc(IOBUF_SIZE);
i=start_bunzip(&bd,src_fd,0,0);
if(!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;
i = read_bunzip(bd, outbuf, IOBUF_SIZE);
if (i <= 0) break;
if (i != safe_write(dst_fd, outbuf, i)) {
i = RETVAL_UNEXPECTED_OUTPUT_EOF;
break;
}
USE_DESKTOP(total_written += i;)
@ -694,13 +708,13 @@ uncompressStream(int src_fd, int dst_fd)
/* Check CRC and release memory */
if(i==RETVAL_LAST_BLOCK) {
if (bd->headerCRC!=bd->totalCRC) {
if (i == RETVAL_LAST_BLOCK) {
if (bd->headerCRC != bd->totalCRC) {
bb_error_msg("data integrity error when decompressing");
} else {
i=RETVAL_OK;
i = RETVAL_OK;
}
} else if (i==RETVAL_UNEXPECTED_OUTPUT_EOF) {
} else if (i == RETVAL_UNEXPECTED_OUTPUT_EOF) {
bb_error_msg("compressed file ends unexpectedly");
} else {
bb_error_msg("decompression failed");
@ -714,18 +728,22 @@ uncompressStream(int src_fd, int dst_fd)
#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."};
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);
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");
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