1 // Copyright (c) 2011 The LevelDB Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. See the AUTHORS file for names of contributors. 4 5 #include "util/testutil.h" 6 7 #include "util/random.h" 8 9 namespace leveldb { 10 namespace test { 11 12 Slice RandomString(Random* rnd, int len, std::string* dst) { 13 dst->resize(len); 14 for (int i = 0; i < len; i++) { 15 (*dst)[i] = static_cast<char>(' ' + rnd->Uniform(95)); // ' ' .. '~' 16 } 17 return Slice(*dst); 18 } 19 20 std::string RandomKey(Random* rnd, int len) { 21 // Make sure to generate a wide variety of characters so we 22 // test the boundary conditions for short-key optimizations. 23 static const char kTestChars[] = { 24 '\0', '\1', 'a', 'b', 'c', 'd', 'e', '\xfd', '\xfe', '\xff' 25 }; 26 std::string result; 27 for (int i = 0; i < len; i++) { 28 result += kTestChars[rnd->Uniform(sizeof(kTestChars))]; 29 } 30 return result; 31 } 32 33 34 extern Slice CompressibleString(Random* rnd, double compressed_fraction, 35 int len, std::string* dst) { 36 int raw = static_cast<int>(len * compressed_fraction); 37 if (raw < 1) raw = 1; 38 std::string raw_data; 39 RandomString(rnd, raw, &raw_data); 40 41 // Duplicate the random data until we have filled "len" bytes 42 dst->clear(); 43 while (dst->size() < len) { 44 dst->append(raw_data); 45 } 46 dst->resize(len); 47 return Slice(*dst); 48 } 49 50 } // namespace test 51 } // namespace leveldb 52
