From 6444c50035c466580ecbd90b5596288204a7d363 Mon Sep 17 00:00:00 2001
From: Yann Collet <cyan@fb.com>
Date: Tue, 28 Aug 2018 18:13:46 -0700
Subject: [PATCH] increases randomness of ddict ptrs

---
 contrib/largeNbDicts/largeNbDicts.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/contrib/largeNbDicts/largeNbDicts.c b/contrib/largeNbDicts/largeNbDicts.c
index 4c05e24ec..193362493 100644
--- a/contrib/largeNbDicts/largeNbDicts.c
+++ b/contrib/largeNbDicts/largeNbDicts.c
@@ -237,6 +237,12 @@ static ddict_collection_t createDDictCollection(const void* dictBuffer, size_t d
 void shuffleDictionaries(ddict_collection_t dicts)
 {
     size_t const nbDicts = dicts.nbDDict;
+    for (size_t r=0; r<nbDicts; r++) {
+        size_t const d = rand() % nbDicts;
+        ZSTD_DDict* tmpd = dicts.ddicts[d];
+        dicts.ddicts[d] = dicts.ddicts[r];
+        dicts.ddicts[r] = tmpd;
+    }
     for (size_t r=0; r<nbDicts; r++) {
         size_t const d1 = rand() % nbDicts;
         size_t const d2 = rand() % nbDicts;
@@ -537,14 +543,15 @@ int bad_usage(const char* exeName)
 int main (int argc, const char** argv)
 {
     const char* const exeName = argv[0];
-    int cLevel = CLEVEL_DEFAULT;
-    size_t blockSize = BLOCKSIZE_DEFAULT;
-    size_t nbDicts = 0;
 
     if (argc < 2) return bad_usage(exeName);
     const char* const fileName = argv[1];
 
     const char* dictionary = NULL;
+    int cLevel = CLEVEL_DEFAULT;
+    size_t blockSize = BLOCKSIZE_DEFAULT;
+    size_t nbDicts = 0;  /* auto, 1 dict per block */
+
     for (int argNb = 2; argNb < argc ; argNb++) {
         const char* argument = argv[argNb];
         if (longCommandWArg(&argument, "--clevel=")) { cLevel = readU32FromChar(&argument); continue; }