script:
- CC=clang MOREFLAGS=-fsanitize=address make -C tests test-frametest test-fuzzer
+ - name: Custom LZ4_DISTANCE_MAX
+ script:
+ - MOREFLAGS=-DLZ4_DISTANCE_MAX=8000 make check
+
- name: (Precise) g++ and clang CMake test
dist: precise
script:
- `LZ4_DISTANCE_MAX` : control the maximum offset that the compressor will allow.
Set to 65535 by default, which is the maximum value supported by lz4 format.
Reducing maximum distance will reduce opportunities for LZ4 to find matches,
- hence will produce worse the compression ratio.
- However, a smaller max distance may allow compatibility with specific decoders using limited memory budget.
+ hence will produce a worse compression ratio.
+ However, a smaller max distance can allow compatibility with specific decoders using limited memory budget.
This build macro only influences the compressed output of the compressor.
- `LZ4_DISABLE_DEPRECATE_WARNINGS` : invoking a deprecated function will make the compiler generate a warning.
#define MB *(1 <<20)
#define GB *(1U<<30)
-#if (LZ4_DISTANCE_MAX > 65535) /* max supported by LZ4 format */
+#define LZ4_DISTANCE_ABSOLUTE_MAX 65535
+#if (LZ4_DISTANCE_MAX > LZ4_DISTANCE_ABSOLUTE_MAX) /* max supported by LZ4 format */
# error "LZ4_DISTANCE_MAX is too big : must be <= 65535"
#endif
forwardH = LZ4_hashPosition(forwardIp, tableType);
LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
+ DEBUGLOG(7, "candidate at pos=%u (offset=%u \n", matchIndex, current - matchIndex);
if ((dictIssue == dictSmall) && (matchIndex < prefixIdxLimit)) { continue; } /* match outside of valid area */
assert(matchIndex < current);
- if ((tableType != byU16) && (matchIndex+LZ4_DISTANCE_MAX < current)) { continue; } /* too far */
- if (tableType == byU16) { assert((current - matchIndex) <= LZ4_DISTANCE_MAX); } /* too_far presumed impossible with byU16 */
+ if ( ((tableType != byU16) || (LZ4_DISTANCE_MAX < LZ4_DISTANCE_ABSOLUTE_MAX))
+ && (matchIndex+LZ4_DISTANCE_MAX < current)) {
+ continue;
+ } /* too far */
+ assert((current - matchIndex) <= LZ4_DISTANCE_MAX); /* match now expected within distance */
if (LZ4_read32(match) == LZ4_read32(ip)) {
if (maybe_extMem) offset = current - matchIndex;
LZ4_putIndexOnHash(current, h, cctx->hashTable, tableType);
assert(matchIndex < current);
if ( ((dictIssue==dictSmall) ? (matchIndex >= prefixIdxLimit) : 1)
- && ((tableType==byU16) ? 1 : (matchIndex+LZ4_DISTANCE_MAX >= current))
+ && (((tableType==byU16) && (LZ4_DISTANCE_MAX == LZ4_DISTANCE_ABSOLUTE_MAX)) ? 1 : (matchIndex+LZ4_DISTANCE_MAX >= current))
&& (LZ4_read32(match) == LZ4_read32(ip)) ) {
token=op++;
*token=0;
test-fuzzer32: test-fuzzer
test-frametest: frametest
- ./frametest $(FUZZER_TIME)
+ ./frametest -v $(FUZZER_TIME)
test-frametest32: CFLAGS += -m32
test-frametest32: test-frametest
#define LZ4F_STATIC_LINKING_ONLY
#include "lz4frame.h"
#include "lz4frame.h"
+#define LZ4_STATIC_LINKING_ONLY /* LZ4_DISTANCE_MAX */
#include "lz4.h" /* LZ4_VERSION_STRING */
#define XXH_STATIC_LINKING_ONLY
#include "xxhash.h" /* XXH64 */
cdict, NULL) );
DISPLAYLEVEL(3, "compressed %u bytes into %u bytes \n",
(unsigned)dictSize, (unsigned)cSizeWithDict);
- if (cSizeWithDict >= cSizeNoDict) goto _output_error; /* must be more efficient */
+ if ((LZ4_DISTANCE_MAX > dictSize) && (cSizeWithDict >= cSizeNoDict)) goto _output_error; /* must be more efficient */
crcOrig = XXH64(CNBuffer, dictSize, 0);
DISPLAYLEVEL(3, "LZ4F_decompress_usingDict : ");