Method execute

src/linux/perf.cpp:126–185

private:
  void execute()
  {
    // NOTE: The supervisor childhook places perf in its own process group
    // and will kill the perf process when the parent dies.
    Try<Subprocess> _perf = subprocess(
        "perf",
        argv,
        Subprocess::PIPE(),
        Subprocess::PIPE(),
        Subprocess::PIPE(),
        nullptr,
        None(),
        None(),
        {},
        {Subprocess::ChildHook::SUPERVISOR()});

    if (_perf.isError()) {
      promise.fail("Failed to launch perf process: " + _perf.error());
      terminate(self());
      return;
    }
    perf = _perf.get();

    // Wait for the process to exit.
    await(perf->status(),
          io::read(perf->out().get()),
          io::read(perf->err().get()))
      .onReady(defer(self(), [this](const tuple<
          Future<Option<int>>,
          Future<string>,
          Future<string>>& results) {
        const Future<Option<int>>& status = std::get<0>(results);
        const Future<string>& output = std::get<1>(results);

        Option<Error> error = None();

        if (!status.isReady()) {
          error = Error("Failed to execute perf: " +
                        (status.isFailed() ? status.failure() : "discarded"));
        } else if (status->isNone()) {
          error = Error("Failed to execute perf: failed to reap");
        } else if (status->get() != 0) {
          error = Error("Failed to execute perf: " +
                        WSTRINGIFY(status->get()));
        } else if (!output.isReady()) {
          error = Error("Failed to read perf output: " +
                        (output.isFailed() ? output.failure() : "discarded"));
        }

        if (error.isSome()) {
          promise.fail(error->message);
          terminate(self());
          return;
        }

        promise.set(output.get());
        terminate(self());
        return;