1 files changed, 84 insertions, 0 deletions
diff --git a/src/zstd/tests/fuzz/zstd_helpers.c b/src/zstd/tests/fuzz/zstd_helpers.c
new file mode 100644
index 00000000..60289847
--- /dev/null
+++ b/src/zstd/tests/fuzz/zstd_helpers.c
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2016-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ */
+
+#define ZSTD_STATIC_LINKING_ONLY
+
+#include "zstd_helpers.h"
+#include "fuzz_helpers.h"
+#include "zstd.h"
+
+static void set(ZSTD_CCtx *cctx, ZSTD_cParameter param, unsigned value)
+{
+    FUZZ_ZASSERT(ZSTD_CCtx_setParameter(cctx, param, value));
+}
+
+static void setRand(ZSTD_CCtx *cctx, ZSTD_cParameter param, unsigned min,
+                    unsigned max, uint32_t *state) {
+    unsigned const value = FUZZ_rand32(state, min, max);
+    set(cctx, param, value);
+}
+
+ZSTD_compressionParameters FUZZ_randomCParams(size_t srcSize, uint32_t *state)
+{
+    /* Select compression parameters */
+    ZSTD_compressionParameters cParams;
+    cParams.windowLog = FUZZ_rand32(state, ZSTD_WINDOWLOG_MIN, 15);
+    cParams.hashLog = FUZZ_rand32(state, ZSTD_HASHLOG_MIN, 15);
+    cParams.chainLog = FUZZ_rand32(state, ZSTD_CHAINLOG_MIN, 16);
+    cParams.searchLog = FUZZ_rand32(state, ZSTD_SEARCHLOG_MIN, 9);
+    cParams.searchLength = FUZZ_rand32(state, ZSTD_SEARCHLENGTH_MIN,
+                                              ZSTD_SEARCHLENGTH_MAX);
+    cParams.targetLength = FUZZ_rand32(state, ZSTD_TARGETLENGTH_MIN,
+                                              ZSTD_TARGETLENGTH_MAX);
+    cParams.strategy = FUZZ_rand32(state, ZSTD_fast, ZSTD_btultra);
+    return ZSTD_adjustCParams(cParams, srcSize, 0);
+}
+
+ZSTD_frameParameters FUZZ_randomFParams(uint32_t *state)
+{
+    /* Select frame parameters */
+    ZSTD_frameParameters fParams;
+    fParams.contentSizeFlag = FUZZ_rand32(state, 0, 1);
+    fParams.checksumFlag = FUZZ_rand32(state, 0, 1);
+    fParams.noDictIDFlag = FUZZ_rand32(state, 0, 1);
+    return fParams;
+}
+
+ZSTD_parameters FUZZ_randomParams(size_t srcSize, uint32_t *state)
+{
+    ZSTD_parameters params;
+    params.cParams = FUZZ_randomCParams(srcSize, state);
+    params.fParams = FUZZ_randomFParams(state);
+    return params;
+}
+
+void FUZZ_setRandomParameters(ZSTD_CCtx *cctx, size_t srcSize, uint32_t *state)
+{
+    ZSTD_compressionParameters cParams = FUZZ_randomCParams(srcSize, state);
+    set(cctx, ZSTD_p_windowLog, cParams.windowLog);
+    set(cctx, ZSTD_p_hashLog, cParams.hashLog);
+    set(cctx, ZSTD_p_chainLog, cParams.chainLog);
+    set(cctx, ZSTD_p_searchLog, cParams.searchLog);
+    set(cctx, ZSTD_p_minMatch, cParams.searchLength);
+    set(cctx, ZSTD_p_targetLength, cParams.targetLength);
+    set(cctx, ZSTD_p_compressionStrategy, cParams.strategy);
+    /* Select frame parameters */
+    setRand(cctx, ZSTD_p_contentSizeFlag, 0, 1, state);
+    setRand(cctx, ZSTD_p_checksumFlag, 0, 1, state);
+    setRand(cctx, ZSTD_p_dictIDFlag, 0, 1, state);
+    /* Select long distance matchig parameters */
+    setRand(cctx, ZSTD_p_enableLongDistanceMatching, 0, 1, state);
+    setRand(cctx, ZSTD_p_ldmHashLog, ZSTD_HASHLOG_MIN, 16, state);
+    setRand(cctx, ZSTD_p_ldmMinMatch, ZSTD_LDM_MINMATCH_MIN,
+            ZSTD_LDM_MINMATCH_MAX, state);
+    setRand(cctx, ZSTD_p_ldmBucketSizeLog, 0, ZSTD_LDM_BUCKETSIZELOG_MAX,
+            state);
+    setRand(cctx, ZSTD_p_ldmHashEveryLog, 0,
+            ZSTD_WINDOWLOG_MAX - ZSTD_HASHLOG_MIN, state);
+}