src/profiling/memory/client.cc

/*
 * Copyright (C) 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "src/profiling/memory/client.h"

#include <inttypes.h>
#include <sys/socket.h>

#include <atomic>

#include "perfetto/base/logging.h"
#include "perfetto/base/utils.h"
#include "src/profiling/memory/transport_data.h"

namespace perfetto {

BorrowedSocket::BorrowedSocket(base::ScopedFile fd, SocketPool* socket_pool)
    : fd_(std::move(fd)), socket_pool_(socket_pool) {}

int BorrowedSocket::operator*() {
  return get();
}

int BorrowedSocket::get() {
  return *fd_;
}

void BorrowedSocket::Close() {
  fd_.reset();
}

BorrowedSocket::~BorrowedSocket() {
  if (socket_pool_ != nullptr)
    socket_pool_->Return(std::move(fd_));
}

SocketPool::SocketPool(std::vector<base::ScopedFile> sockets)
    : sockets_(std::move(sockets)), available_sockets_(sockets_.size()) {}

BorrowedSocket SocketPool::Borrow() {
  std::unique_lock<std::mutex> lck_(mtx_);
  if (available_sockets_ == 0)
    cv_.wait(lck_, [this] { return available_sockets_ > 0; });
  PERFETTO_CHECK(available_sockets_ > 0);
  return {std::move(sockets_[--available_sockets_]), this};
}

void SocketPool::Return(base::ScopedFile sock) {
  std::unique_lock<std::mutex> lck_(mtx_);
  PERFETTO_CHECK(available_sockets_ < sockets_.size());
  sockets_[available_sockets_++] = std::move(sock);
  if (available_sockets_ == 1) {
    lck_.unlock();
    cv_.notify_one();
  }
}

}  // namespace perfetto