diff options
Diffstat (limited to 'winsup/bz2lib/bzip2recover.c')
-rw-r--r-- | winsup/bz2lib/bzip2recover.c | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/winsup/bz2lib/bzip2recover.c b/winsup/bz2lib/bzip2recover.c new file mode 100644 index 0000000..ba3d175 --- /dev/null +++ b/winsup/bz2lib/bzip2recover.c @@ -0,0 +1,435 @@ + +/*-----------------------------------------------------------*/ +/*--- 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) + + +Char inFileName[2000]; +Char outFileName[2000]; +Char progName[2000]; + +UInt32 bytesOut = 0; +UInt32 bytesIn = 0; + + +/*---------------------------------------------------*/ +/*--- 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 ---*/ +/*---------------------------------------------------*/ + +typedef + struct { + FILE* handle; + Int32 buffer; + Int32 buffLive; + Char mode; + } + BitStream; + + +/*---------------------------------------------*/ +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 ---*/ +/*-----------------------------------------------------------*/ |