Function synchronized

src/exec/exec.cpp:743–882

Status MesosExecutorDriver::start()
{
  synchronized (mutex) {
    if (status != DRIVER_NOT_STARTED) {
      return status;
    }

    // Set stream buffering mode to flush on newlines so that we
    // capture logs from user processes even when output is redirected
    // to a file. On POSIX, the buffer size is determined by the system
    // when the `buf` parameter is null. On Windows we have to specify
    // the size, so we use 1024 bytes, a number that is arbitrary, but
    // large enough to not affect performance.
    const size_t bufferSize =
#ifdef __WINDOWS__
      1024;
#else // __WINDOWS__
      0;
#endif // __WINDOWS__
    setvbuf(stdout, nullptr, _IOLBF, bufferSize);
    setvbuf(stderr, nullptr, _IOLBF, bufferSize);

    bool local;

    UPID slave;
    SlaveID slaveId;
    FrameworkID frameworkId;
    ExecutorID executorId;
    string workDirectory;
    bool checkpoint;

    Option<string> value;
    std::istringstream iss;
    hashmap<string, string> env(environment);

    // Check if this is local (for example, for testing).
    local = env.contains("MESOS_LOCAL");

    // Get slave PID from environment.
    value = env.get("MESOS_SLAVE_PID");
    if (value.isNone()) {
      EXIT(EXIT_FAILURE)
        << "Expecting 'MESOS_SLAVE_PID' to be set in the environment";
    }

    slave = UPID(value.get());
    CHECK(slave) << "Cannot parse MESOS_SLAVE_PID '" << value.get() << "'";

    // Get slave ID from environment.
    value = env.get("MESOS_SLAVE_ID");
    if (value.isNone()) {
      EXIT(EXIT_FAILURE)
        << "Expecting 'MESOS_SLAVE_ID' to be set in the environment";
    }
    slaveId.set_value(value.get());

    // Get framework ID from environment.
    value = env.get("MESOS_FRAMEWORK_ID");
    if (value.isNone()) {
      EXIT(EXIT_FAILURE)