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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include "util/testutil.h"
#include "util/random.h"
namespace leveldb {
namespace test {
Slice RandomString(Random* rnd, int len, std::string* dst) {
dst->resize(len);
for (int i = 0; i < len; i++) {
(*dst)[i] = static_cast<char>(' ' + rnd->Uniform(95)); // ' ' .. '~'
}
return Slice(*dst);
}
std::string RandomKey(Random* rnd, int len) {
// Make sure to generate a wide variety of characters so we
// test the boundary conditions for short-key optimizations.
static const char kTestChars[] = {
'\0', '\1', 'a', 'b', 'c', 'd', 'e', '\xfd', '\xfe', '\xff'
};
std::string result;
for (int i = 0; i < len; i++) {
result += kTestChars[rnd->Uniform(sizeof(kTestChars))];
}
return result;
}
extern Slice CompressibleString(Random* rnd, double compressed_fraction,
size_t len, std::string* dst) {
int raw = static_cast<int>(len * compressed_fraction);
if (raw < 1) raw = 1;
std::string raw_data;
RandomString(rnd, raw, &raw_data);
// Duplicate the random data until we have filled "len" bytes
dst->clear();
while (dst->size() < len) {
dst->append(raw_data);
}
dst->resize(len);
return Slice(*dst);
}
} // namespace test
} // namespace leveldb