447 lines
12 KiB
C
447 lines
12 KiB
C
/* $NetBSD: bzip2recover.c,v 1.2 2001/06/03 13:39:38 simonb Exp $ */
|
|
|
|
|
|
/*-----------------------------------------------------------*/
|
|
/*--- Block recoverer program for bzip2 ---*/
|
|
/*--- bzip2recover.c ---*/
|
|
/*-----------------------------------------------------------*/
|
|
|
|
/*--
|
|
This program is bzip2recover, a program to attempt data
|
|
salvage from damaged files created by the accompanying
|
|
bzip2-1.0 program.
|
|
|
|
Copyright (C) 1996-2000 Julian R Seward. All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
|
|
1. Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
|
|
2. The origin of this software must not be misrepresented; you must
|
|
not claim that you wrote the original software. If you use this
|
|
software in a product, an acknowledgment in the product
|
|
documentation would be appreciated but is not required.
|
|
|
|
3. Altered source versions must be plainly marked as such, and must
|
|
not be misrepresented as being the original software.
|
|
|
|
4. The name of the author may not be used to endorse or promote
|
|
products derived from this software without specific prior written
|
|
permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
|
|
OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
|
|
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
|
|
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
|
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
|
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
|
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
Julian Seward, Cambridge, UK.
|
|
jseward@acm.org
|
|
bzip2/libbzip2 version 1.0 of 21 March 2000
|
|
--*/
|
|
|
|
/*--
|
|
This program is a complete hack and should be rewritten
|
|
properly. It isn't very complicated.
|
|
--*/
|
|
|
|
#include <stdio.h>
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
typedef unsigned int UInt32;
|
|
typedef int Int32;
|
|
typedef unsigned char UChar;
|
|
typedef char Char;
|
|
typedef unsigned char Bool;
|
|
#define True ((Bool)1)
|
|
#define False ((Bool)0)
|
|
|
|
typedef
|
|
struct {
|
|
FILE* handle;
|
|
Int32 buffer;
|
|
Int32 buffLive;
|
|
Char mode;
|
|
}
|
|
BitStream;
|
|
|
|
|
|
Char inFileName[2000];
|
|
Char outFileName[2000];
|
|
Char progName[2000];
|
|
|
|
UInt32 bytesOut = 0;
|
|
UInt32 bytesIn = 0;
|
|
|
|
void readError ( void );
|
|
void writeError ( void );
|
|
void mallocFail ( Int32 n );
|
|
BitStream* bsOpenReadStream ( FILE* stream );
|
|
BitStream* bsOpenWriteStream ( FILE* stream );
|
|
void bsPutBit ( BitStream* bs, Int32 bit );
|
|
Int32 bsGetBit ( BitStream* bs );
|
|
void bsClose ( BitStream* bs );
|
|
void bsPutUChar ( BitStream* bs, UChar c );
|
|
void bsPutUInt32 ( BitStream* bs, UInt32 c );
|
|
Bool endsInBz2 ( Char* name );
|
|
|
|
/*---------------------------------------------------*/
|
|
/*--- I/O errors ---*/
|
|
/*---------------------------------------------------*/
|
|
|
|
/*---------------------------------------------*/
|
|
void readError ( void )
|
|
{
|
|
fprintf ( stderr,
|
|
"%s: I/O error reading `%s', possible reason follows.\n",
|
|
progName, inFileName );
|
|
perror ( progName );
|
|
fprintf ( stderr, "%s: warning: output file(s) may be incomplete.\n",
|
|
progName );
|
|
exit ( 1 );
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
void writeError ( void )
|
|
{
|
|
fprintf ( stderr,
|
|
"%s: I/O error reading `%s', possible reason follows.\n",
|
|
progName, inFileName );
|
|
perror ( progName );
|
|
fprintf ( stderr, "%s: warning: output file(s) may be incomplete.\n",
|
|
progName );
|
|
exit ( 1 );
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
void mallocFail ( Int32 n )
|
|
{
|
|
fprintf ( stderr,
|
|
"%s: malloc failed on request for %d bytes.\n",
|
|
progName, n );
|
|
fprintf ( stderr, "%s: warning: output file(s) may be incomplete.\n",
|
|
progName );
|
|
exit ( 1 );
|
|
}
|
|
|
|
/*---------------------------------------------------*/
|
|
/*--- Bit stream I/O ---*/
|
|
/*---------------------------------------------------*/
|
|
|
|
/*---------------------------------------------*/
|
|
BitStream* bsOpenReadStream ( FILE* stream )
|
|
{
|
|
BitStream *bs = malloc ( sizeof(BitStream) );
|
|
if (bs == NULL) mallocFail ( sizeof(BitStream) );
|
|
bs->handle = stream;
|
|
bs->buffer = 0;
|
|
bs->buffLive = 0;
|
|
bs->mode = 'r';
|
|
return bs;
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
BitStream* bsOpenWriteStream ( FILE* stream )
|
|
{
|
|
BitStream *bs = malloc ( sizeof(BitStream) );
|
|
if (bs == NULL) mallocFail ( sizeof(BitStream) );
|
|
bs->handle = stream;
|
|
bs->buffer = 0;
|
|
bs->buffLive = 0;
|
|
bs->mode = 'w';
|
|
return bs;
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
void bsPutBit ( BitStream* bs, Int32 bit )
|
|
{
|
|
if (bs->buffLive == 8) {
|
|
Int32 retVal = putc ( (UChar) bs->buffer, bs->handle );
|
|
if (retVal == EOF) writeError();
|
|
bytesOut++;
|
|
bs->buffLive = 1;
|
|
bs->buffer = bit & 0x1;
|
|
} else {
|
|
bs->buffer = ( (bs->buffer << 1) | (bit & 0x1) );
|
|
bs->buffLive++;
|
|
};
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
/*--
|
|
Returns 0 or 1, or 2 to indicate EOF.
|
|
--*/
|
|
Int32 bsGetBit ( BitStream* bs )
|
|
{
|
|
if (bs->buffLive > 0) {
|
|
bs->buffLive --;
|
|
return ( ((bs->buffer) >> (bs->buffLive)) & 0x1 );
|
|
} else {
|
|
Int32 retVal = getc ( bs->handle );
|
|
if ( retVal == EOF ) {
|
|
if (errno != 0) readError();
|
|
return 2;
|
|
}
|
|
bs->buffLive = 7;
|
|
bs->buffer = retVal;
|
|
return ( ((bs->buffer) >> 7) & 0x1 );
|
|
}
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
void bsClose ( BitStream* bs )
|
|
{
|
|
Int32 retVal;
|
|
|
|
if ( bs->mode == 'w' ) {
|
|
while ( bs->buffLive < 8 ) {
|
|
bs->buffLive++;
|
|
bs->buffer <<= 1;
|
|
};
|
|
retVal = putc ( (UChar) (bs->buffer), bs->handle );
|
|
if (retVal == EOF) writeError();
|
|
bytesOut++;
|
|
retVal = fflush ( bs->handle );
|
|
if (retVal == EOF) writeError();
|
|
}
|
|
retVal = fclose ( bs->handle );
|
|
if (retVal == EOF) {
|
|
if (bs->mode == 'w') writeError(); else readError();
|
|
}
|
|
free ( bs );
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
void bsPutUChar ( BitStream* bs, UChar c )
|
|
{
|
|
Int32 i;
|
|
for (i = 7; i >= 0; i--)
|
|
bsPutBit ( bs, (((UInt32) c) >> i) & 0x1 );
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
void bsPutUInt32 ( BitStream* bs, UInt32 c )
|
|
{
|
|
Int32 i;
|
|
|
|
for (i = 31; i >= 0; i--)
|
|
bsPutBit ( bs, (c >> i) & 0x1 );
|
|
}
|
|
|
|
|
|
/*---------------------------------------------*/
|
|
Bool endsInBz2 ( Char* name )
|
|
{
|
|
Int32 n = strlen ( name );
|
|
if (n <= 4) return False;
|
|
return
|
|
(name[n-4] == '.' &&
|
|
name[n-3] == 'b' &&
|
|
name[n-2] == 'z' &&
|
|
name[n-1] == '2');
|
|
}
|
|
|
|
|
|
/*---------------------------------------------------*/
|
|
/*--- ---*/
|
|
/*---------------------------------------------------*/
|
|
|
|
#define BLOCK_HEADER_HI 0x00003141UL
|
|
#define BLOCK_HEADER_LO 0x59265359UL
|
|
|
|
#define BLOCK_ENDMARK_HI 0x00001772UL
|
|
#define BLOCK_ENDMARK_LO 0x45385090UL
|
|
|
|
|
|
UInt32 bStart[20000];
|
|
UInt32 bEnd[20000];
|
|
UInt32 rbStart[20000];
|
|
UInt32 rbEnd[20000];
|
|
|
|
Int32 main ( Int32 argc, Char** argv )
|
|
{
|
|
FILE* inFile;
|
|
FILE* outFile;
|
|
BitStream* bsIn, *bsWr;
|
|
Int32 currBlock, b, wrBlock;
|
|
UInt32 bitsRead;
|
|
Int32 rbCtr;
|
|
|
|
|
|
UInt32 buffHi, buffLo, blockCRC;
|
|
Char* p;
|
|
|
|
strcpy ( progName, argv[0] );
|
|
inFileName[0] = outFileName[0] = 0;
|
|
|
|
fprintf ( stderr, "bzip2recover 1.0: extracts blocks from damaged .bz2 files.\n" );
|
|
|
|
if (argc != 2) {
|
|
fprintf ( stderr, "%s: usage is `%s damaged_file_name'.\n",
|
|
progName, progName );
|
|
exit(1);
|
|
}
|
|
|
|
strcpy ( inFileName, argv[1] );
|
|
|
|
inFile = fopen ( inFileName, "rb" );
|
|
if (inFile == NULL) {
|
|
fprintf ( stderr, "%s: can't read `%s'\n", progName, inFileName );
|
|
exit(1);
|
|
}
|
|
|
|
bsIn = bsOpenReadStream ( inFile );
|
|
fprintf ( stderr, "%s: searching for block boundaries ...\n", progName );
|
|
|
|
bitsRead = 0;
|
|
buffHi = buffLo = 0;
|
|
currBlock = 0;
|
|
bStart[currBlock] = 0;
|
|
|
|
rbCtr = 0;
|
|
|
|
while (True) {
|
|
b = bsGetBit ( bsIn );
|
|
bitsRead++;
|
|
if (b == 2) {
|
|
if (bitsRead >= bStart[currBlock] &&
|
|
(bitsRead - bStart[currBlock]) >= 40) {
|
|
bEnd[currBlock] = bitsRead-1;
|
|
if (currBlock > 0)
|
|
fprintf ( stderr, " block %d runs from %d to %d (incomplete)\n",
|
|
currBlock, bStart[currBlock], bEnd[currBlock] );
|
|
} else
|
|
currBlock--;
|
|
break;
|
|
}
|
|
buffHi = (buffHi << 1) | (buffLo >> 31);
|
|
buffLo = (buffLo << 1) | (b & 1);
|
|
if ( ( (buffHi & 0x0000ffff) == BLOCK_HEADER_HI
|
|
&& buffLo == BLOCK_HEADER_LO)
|
|
||
|
|
( (buffHi & 0x0000ffff) == BLOCK_ENDMARK_HI
|
|
&& buffLo == BLOCK_ENDMARK_LO)
|
|
) {
|
|
if (bitsRead > 49)
|
|
bEnd[currBlock] = bitsRead-49; else
|
|
bEnd[currBlock] = 0;
|
|
if (currBlock > 0 &&
|
|
(bEnd[currBlock] - bStart[currBlock]) >= 130) {
|
|
fprintf ( stderr, " block %d runs from %d to %d\n",
|
|
rbCtr+1, bStart[currBlock], bEnd[currBlock] );
|
|
rbStart[rbCtr] = bStart[currBlock];
|
|
rbEnd[rbCtr] = bEnd[currBlock];
|
|
rbCtr++;
|
|
}
|
|
currBlock++;
|
|
|
|
bStart[currBlock] = bitsRead;
|
|
}
|
|
}
|
|
|
|
bsClose ( bsIn );
|
|
|
|
/*-- identified blocks run from 1 to rbCtr inclusive. --*/
|
|
|
|
if (rbCtr < 1) {
|
|
fprintf ( stderr,
|
|
"%s: sorry, I couldn't find any block boundaries.\n",
|
|
progName );
|
|
exit(1);
|
|
};
|
|
|
|
fprintf ( stderr, "%s: splitting into blocks\n", progName );
|
|
|
|
inFile = fopen ( inFileName, "rb" );
|
|
if (inFile == NULL) {
|
|
fprintf ( stderr, "%s: can't open `%s'\n", progName, inFileName );
|
|
exit(1);
|
|
}
|
|
bsIn = bsOpenReadStream ( inFile );
|
|
|
|
/*-- placate gcc's dataflow analyser --*/
|
|
blockCRC = 0; bsWr = 0;
|
|
|
|
bitsRead = 0;
|
|
outFile = NULL;
|
|
wrBlock = 0;
|
|
while (True) {
|
|
b = bsGetBit(bsIn);
|
|
if (b == 2) break;
|
|
buffHi = (buffHi << 1) | (buffLo >> 31);
|
|
buffLo = (buffLo << 1) | (b & 1);
|
|
if (bitsRead == 47+rbStart[wrBlock])
|
|
blockCRC = (buffHi << 16) | (buffLo >> 16);
|
|
|
|
if (outFile != NULL && bitsRead >= rbStart[wrBlock]
|
|
&& bitsRead <= rbEnd[wrBlock]) {
|
|
bsPutBit ( bsWr, b );
|
|
}
|
|
|
|
bitsRead++;
|
|
|
|
if (bitsRead == rbEnd[wrBlock]+1) {
|
|
if (outFile != NULL) {
|
|
bsPutUChar ( bsWr, 0x17 ); bsPutUChar ( bsWr, 0x72 );
|
|
bsPutUChar ( bsWr, 0x45 ); bsPutUChar ( bsWr, 0x38 );
|
|
bsPutUChar ( bsWr, 0x50 ); bsPutUChar ( bsWr, 0x90 );
|
|
bsPutUInt32 ( bsWr, blockCRC );
|
|
bsClose ( bsWr );
|
|
}
|
|
if (wrBlock >= rbCtr) break;
|
|
wrBlock++;
|
|
} else
|
|
if (bitsRead == rbStart[wrBlock]) {
|
|
outFileName[0] = 0;
|
|
sprintf ( outFileName, "rec%4d", wrBlock+1 );
|
|
for (p = outFileName; *p != 0; p++) if (*p == ' ') *p = '0';
|
|
strcat ( outFileName, inFileName );
|
|
if ( !endsInBz2(outFileName)) strcat ( outFileName, ".bz2" );
|
|
|
|
fprintf ( stderr, " writing block %d to `%s' ...\n",
|
|
wrBlock+1, outFileName );
|
|
|
|
outFile = fopen ( outFileName, "wb" );
|
|
if (outFile == NULL) {
|
|
fprintf ( stderr, "%s: can't write `%s'\n",
|
|
progName, outFileName );
|
|
exit(1);
|
|
}
|
|
bsWr = bsOpenWriteStream ( outFile );
|
|
bsPutUChar ( bsWr, 'B' ); bsPutUChar ( bsWr, 'Z' );
|
|
bsPutUChar ( bsWr, 'h' ); bsPutUChar ( bsWr, '9' );
|
|
bsPutUChar ( bsWr, 0x31 ); bsPutUChar ( bsWr, 0x41 );
|
|
bsPutUChar ( bsWr, 0x59 ); bsPutUChar ( bsWr, 0x26 );
|
|
bsPutUChar ( bsWr, 0x53 ); bsPutUChar ( bsWr, 0x59 );
|
|
}
|
|
}
|
|
|
|
fprintf ( stderr, "%s: finished\n", progName );
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/*-----------------------------------------------------------*/
|
|
/*--- end bzip2recover.c ---*/
|
|
/*-----------------------------------------------------------*/
|