//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.

//  This source code is licensed under both the GPLv2 (found in the

//  COPYING file in the root directory) and Apache 2.0 License

//  (found in the LICENSE.Apache file in the root directory).

//

// 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 "db/malloc_stats.h"

#include <cstring>

#include <memory>

#include "port/jemalloc_helper.h"

namespace ROCKSDB_NAMESPACE {

#ifdef ROCKSDB_JEMALLOC

struct MallocStatus {

  char* cur;

  char* end;

};

static void GetJemallocStatus(void* mstat_arg, const char* status) {

  MallocStatus* mstat = static_cast<MallocStatus*>(mstat_arg);

  size_t status_len = status ? strlen(status) : 0;

  size_t buf_size = (size_t)(mstat->end - mstat->cur);

  if (!status_len || status_len > buf_size) {

    return;

  }

  snprintf(mstat->cur, buf_size, "%s", status);

  mstat->cur += status_len;

}

void DumpMallocStats(std::string* stats) {

  if (!HasJemalloc()) {

    return;

  }

  MallocStatus mstat;

  const unsigned int kMallocStatusLen = 1000000;

  std::unique_ptr<char[]> buf{new char[kMallocStatusLen + 1]};

  mstat.cur = buf.get();

  mstat.end = buf.get() + kMallocStatusLen;

  malloc_stats_print(GetJemallocStatus, &mstat, "");

  stats->append(buf.get());

}

#else

void DumpMallocStats(std::string*) {}

#endif  // ROCKSDB_JEMALLOC

}  // namespace ROCKSDB_NAMESPACE