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author | yann.collet.73@gmail.com <yann.collet.73@gmail.com@650e7d94-2a16-8b24-b05c-7c0b3f6821cd> | 2012-10-24 12:59:19 (GMT) |
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committer | yann.collet.73@gmail.com <yann.collet.73@gmail.com@650e7d94-2a16-8b24-b05c-7c0b3f6821cd> | 2012-10-24 12:59:19 (GMT) |
commit | b1e707f77277441feae978f501ac3455e8bc9b25 (patch) | |
tree | 2173b61747ec89799d7bf8176bd5ba591d7409fc /fuzzer.c | |
parent | 66be4025df5d1e746161e77d6ab394e646c6b682 (diff) | |
download | lz4-b1e707f77277441feae978f501ac3455e8bc9b25.zip lz4-b1e707f77277441feae978f501ac3455e8bc9b25.tar.gz lz4-b1e707f77277441feae978f501ac3455e8bc9b25.tar.bz2 |
- Corrected issue 31 : LZ4 correctly accepts compressing data when the output buffer has exactly the required size (it was a bit over-cautious in previous version).
- Added : a fuzzer tool
Thanks to Andrew Mahone, for contribution on both points
git-svn-id: https://lz4.googlecode.com/svn/trunk@79 650e7d94-2a16-8b24-b05c-7c0b3f6821cd
Diffstat (limited to 'fuzzer.c')
-rw-r--r-- | fuzzer.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/fuzzer.c b/fuzzer.c new file mode 100644 index 0000000..2f75923 --- /dev/null +++ b/fuzzer.c @@ -0,0 +1,165 @@ +/*
+ fuzzer.c - Fuzzer test tool for LZ4
+ Copyright (C) Andrew Mahone - Yann Collet 2012
+ Original code by Andrew Mahone / Modified by Yann Collet
+ GPL v2 License
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+ You can contact the author at :
+ - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
+ - LZ4 source repository : http://code.google.com/p/lz4/
+*/
+
+//**************************************
+// Remove Visual warning messages
+//**************************************
+#define _CRT_SECURE_NO_WARNINGS // fgets
+
+
+//**************************************
+// Includes
+//**************************************
+#include <stdlib.h>
+#include <stdio.h> // fgets
+#include <sys/timeb.h> // timeb
+#include "lz4.h"
+
+
+//**************************************
+// Constants
+//**************************************
+#define NB_ATTEMPTS (1<<18)
+#define LEN ((1<<15))
+#define SEQ_POW 2
+#define NUM_SEQ (1 << SEQ_POW)
+#define SEQ_MSK ((NUM_SEQ) - 1)
+#define MOD_SEQ(x) ((((x) >> 8) & 255) == 0)
+#define NEW_SEQ(x) ((((x) >> 10) %10) == 0)
+#define PAGE_SIZE 4096
+#define ROUND_PAGE(x) (((x) + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1))
+#define PRIME1 2654435761U
+#define PRIME2 2246822519U
+#define PRIME3 3266489917U
+
+
+
+//*********************************************************
+// Functions
+//*********************************************************
+static int FUZ_GetMilliStart()
+{
+ struct timeb tb;
+ int nCount;
+ ftime( &tb );
+ nCount = (int) (tb.millitm + (tb.time & 0xfffff) * 1000);
+ return nCount;
+}
+
+static int FUZ_GetMilliSpan( int nTimeStart )
+{
+ int nSpan = FUZ_GetMilliStart() - nTimeStart;
+ if ( nSpan < 0 )
+ nSpan += 0x100000 * 1000;
+ return nSpan;
+}
+
+
+unsigned int FUZ_rand(unsigned int* src)
+{
+ *src = ((*src) * PRIME1) + PRIME2;
+ return *src;
+}
+
+
+int test_canary(unsigned char *buf) {
+ int i;
+ for (i = 0; i < 2048; i++)
+ if (buf[i] != buf[i + 2048])
+ return 0;
+ return 1;
+}
+
+//int main(int argc, char *argv[]) {
+int main() {
+ unsigned long long bytes = 0;
+ unsigned long long cbytes = 0;
+ unsigned char buf[LEN];
+# undef max
+# define max LZ4_compressBound(LEN)
+# define avail ROUND_PAGE(max)
+ const int off_full = avail - max;
+ unsigned char cbuf[avail + PAGE_SIZE];
+ unsigned int seed, cur_seq, seeds[NUM_SEQ], timestamp=FUZ_GetMilliStart();
+ int i, j, k, ret, len;
+ char userInput[30] = {0};
+
+ printf("starting LZ4 fuzzer\n");
+ printf("Select an Initialisation number (default : random) : ");
+ fflush(stdout);
+ if ( fgets(userInput, sizeof userInput, stdin) )
+ {
+ if ( sscanf(userInput, "%d", &seed) == 1 ) {}
+ else seed = FUZ_GetMilliSpan(timestamp);
+ }
+ printf("Seed = %u\n", seed);
+
+ for (i = 0; i < 2048; i++)
+ cbuf[avail + i] = cbuf[avail + 2048 + i] = FUZ_rand(&seed) >> 16;
+
+ for (i = 0; i < NB_ATTEMPTS; i++) {
+ printf("\r%7i /%7i\r", i, NB_ATTEMPTS);
+ FUZ_rand(&seed);
+ for (j = 0; j < NUM_SEQ; j++) {
+ seeds[j] = FUZ_rand(&seed) << 8;
+ seeds[j] ^= (FUZ_rand(&seed) >> 8) & 65535;
+ }
+ for (j = 0; j < LEN; j++) {
+ k = FUZ_rand(&seed);
+ if (j == 0 || NEW_SEQ(k))
+ cur_seq = seeds[(FUZ_rand(&seed) >> 16) & SEQ_MSK];
+ if (MOD_SEQ(k)) {
+ k = (FUZ_rand(&seed) >> 16) & SEQ_MSK;
+ seeds[k] = FUZ_rand(&seed) << 8;
+ seeds[k] ^= (FUZ_rand(&seed) >> 8) & 65535;
+ }
+ buf[j] = FUZ_rand(&cur_seq) >> 16;
+ }
+ ret = LZ4_compress_limitedOutput((const char*)buf, (char*)&cbuf[off_full], LEN, max);
+ len = ret;
+
+ // Test compression with output size being exactly what's necessary
+ ret = LZ4_compress_limitedOutput((const char*)buf, (char*)&cbuf[avail-len], LEN, len);
+ if (!test_canary(&cbuf[avail])) { printf("compression overran output buffer: seed %u, len %d, olen %d\n", seed, LEN, len); return 1; }
+ if (ret == 0) { printf("compression failed despite sufficient space: seed %u, len %d\n", seed, LEN); return 1; }
+
+ // Test compression with just one missing byte into output buffer => should fail
+ ret = LZ4_compress_limitedOutput((const char*)buf, (char*)&cbuf[avail-(len-1)], LEN, len-1);
+ if (ret) { printf("compression overran output buffer: seed %u, len %d, olen %d => ret %d", seed, LEN, len-1, ret); return 1; }
+ if (!test_canary(&cbuf[avail])) { printf("compression overran output buffer: seed %u, len %d, olen %d", seed, LEN, len-1); return 1; }
+
+ /* No longer useful
+ // Test compression with not enough output size
+ ret = LZ4_compress_limitedOutput((const char*)buf, (char*)&cbuf[avail-len/2], LEN, len/2);
+ if (!test_canary(&cbuf[avail])) { printf("compression overran output buffer: seed %u, len %d, olen %d", seed, LEN, len/2); return 1; }
+ */
+
+ bytes += LEN;
+ cbytes += len;
+ }
+ printf("all tests completed successfully \n");
+ printf("compression ratio: %0.3f%%\n", (double)cbytes/bytes*100);
+ return 0;
+}
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