libutils/Looper_test_pipe.h

/*
 * Copyright 2020 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.
 */

#pragma once
#include <unistd.h>
/**
 * A pipe class for use when testing or fuzzing Looper
 */
class Pipe {
  public:
    int sendFd;
    int receiveFd;

    Pipe() {
        int fds[2];
        ::pipe(fds);

        receiveFd = fds[0];
        sendFd = fds[1];
    }

    ~Pipe() {
        if (sendFd != -1) {
            ::close(sendFd);
        }

        if (receiveFd != -1) {
            ::close(receiveFd);
        }
    }

    android::status_t writeSignal() {
        ssize_t nWritten = ::write(sendFd, "*", 1);
        return nWritten == 1 ? 0 : -errno;
    }

    android::status_t readSignal() {
        char buf[1];
        ssize_t nRead = ::read(receiveFd, buf, 1);
        return nRead == 1 ? 0 : nRead == 0 ? -EPIPE : -errno;
    }
};