126 lines
3 KiB
C
126 lines
3 KiB
C
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/* A test program written to test robustness to decompression of
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corrupted data. Usage is
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unzcrash filename
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and the program will read the specified file, compress it (in memory),
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and then repeatedly decompress it, each time with a different bit of
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the compressed data inverted, so as to test all possible one-bit errors.
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This should not cause any invalid memory accesses. If it does,
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I want to know about it!
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p.s. As you can see from the above description, the process is
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incredibly slow. A file of size eg 5KB will cause it to run for
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many hours.
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*/
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#include <stdio.h>
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#include <assert.h>
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#include "bzlib.h"
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#define M_BLOCK 1000000
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typedef unsigned char uchar;
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#define M_BLOCK_OUT (M_BLOCK + 1000000)
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uchar inbuf[M_BLOCK];
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uchar outbuf[M_BLOCK_OUT];
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uchar zbuf[M_BLOCK + 600 + (M_BLOCK / 100)];
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int nIn, nOut, nZ;
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static char *bzerrorstrings[] = {
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"OK"
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,"SEQUENCE_ERROR"
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,"PARAM_ERROR"
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,"MEM_ERROR"
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,"DATA_ERROR"
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,"DATA_ERROR_MAGIC"
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,"IO_ERROR"
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,"UNEXPECTED_EOF"
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,"OUTBUFF_FULL"
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,"???" /* for future */
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,"???" /* for future */
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,"???" /* for future */
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,"???" /* for future */
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,"???" /* for future */
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,"???" /* for future */
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};
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void flip_bit ( int bit )
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{
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int byteno = bit / 8;
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int bitno = bit % 8;
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uchar mask = 1 << bitno;
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//fprintf ( stderr, "(byte %d bit %d mask %d)",
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// byteno, bitno, (int)mask );
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zbuf[byteno] ^= mask;
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}
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int main ( int argc, char** argv )
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{
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FILE* f;
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int r;
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int bit;
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int i;
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if (argc != 2) {
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fprintf ( stderr, "usage: unzcrash filename\n" );
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return 1;
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}
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f = fopen ( argv[1], "r" );
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if (!f) {
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fprintf ( stderr, "unzcrash: can't open %s\n", argv[1] );
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return 1;
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}
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nIn = fread ( inbuf, 1, M_BLOCK, f );
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fprintf ( stderr, "%d bytes read\n", nIn );
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nZ = M_BLOCK;
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r = BZ2_bzBuffToBuffCompress (
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zbuf, &nZ, inbuf, nIn, 9, 0, 30 );
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assert (r == BZ_OK);
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fprintf ( stderr, "%d after compression\n", nZ );
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for (bit = 0; bit < nZ*8; bit++) {
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fprintf ( stderr, "bit %d ", bit );
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flip_bit ( bit );
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nOut = M_BLOCK_OUT;
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r = BZ2_bzBuffToBuffDecompress (
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outbuf, &nOut, zbuf, nZ, 0, 0 );
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fprintf ( stderr, " %d %s ", r, bzerrorstrings[-r] );
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if (r != BZ_OK) {
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fprintf ( stderr, "\n" );
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} else {
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if (nOut != nIn) {
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fprintf(stderr, "nIn/nOut mismatch %d %d\n", nIn, nOut );
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return 1;
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} else {
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for (i = 0; i < nOut; i++)
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if (inbuf[i] != outbuf[i]) {
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fprintf(stderr, "mismatch at %d\n", i );
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return 1;
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}
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if (i == nOut) fprintf(stderr, "really ok!\n" );
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}
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}
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flip_bit ( bit );
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}
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#if 0
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assert (nOut == nIn);
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for (i = 0; i < nOut; i++) {
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if (inbuf[i] != outbuf[i]) {
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fprintf ( stderr, "difference at %d !\n", i );
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return 1;
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}
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}
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#endif
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fprintf ( stderr, "all ok\n" );
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return 0;
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}
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