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authorDenis Vlasenko2007-04-10 17:16:33 +0000
committerDenis Vlasenko2007-04-10 17:16:33 +0000
commitb38cf3ff8a31b2b35d6bcfb1513d568d1977bcba (patch)
tree16da2cd8c469815f4506b59c73b3668b694ea316
parenta9d7d24e1f524bb7528aa881265fe8f826023751 (diff)
downloadbusybox-b38cf3ff8a31b2b35d6bcfb1513d568d1977bcba.zip
busybox-b38cf3ff8a31b2b35d6bcfb1513d568d1977bcba.tar.gz
bunzip2: big style cleanup. No code changes apart from one s/write/safe_write/
(verified with objdump).
-rw-r--r--archival/libunarchive/decompress_bunzip2.c398
1 files changed, 208 insertions, 190 deletions
diff --git a/archival/libunarchive/decompress_bunzip2.c b/archival/libunarchive/decompress_bunzip2.c
index dd2e1dd..75d225b 100644
--- a/archival/libunarchive/decompress_bunzip2.c
+++ b/archival/libunarchive/decompress_bunzip2.c
@@ -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