Merge "Do not call exit() immediately after serving sideload"

#include <string.h>

#include <unistd.h>

#include <chrono>

#include <functional>

#include <memory>

#include <set>

  return kMinadbdSuccess;

}

static bool WaitForSocketClose(int fd, std::chrono::milliseconds timeout) {

  const auto begin = std::chrono::steady_clock::now();

  const auto end = begin + timeout;

  while (std::chrono::steady_clock::now() < end) {

    // We don't care about reading the socket, we just want to wait until

    // socket closes. In this case .events = 0 will tell the kernel to wait

    // for close events.

    struct pollfd pfd = { .fd = fd, .events = 0 };

    auto timeout_ms = std::chrono::duration_cast<std::chrono::milliseconds>(

                          end - std::chrono::steady_clock::now())

                          .count();

    int rc = TEMP_FAILURE_RETRY(adb_poll(&pfd, 1, timeout_ms));

    if (rc == 1) {

      LOG(INFO) << "revents: " << pfd.revents;

      if (pfd.revents & (POLLHUP | POLLRDHUP)) {

        return true;

      }

    } else {

      PLOG(ERROR) << "poll() failed";

      // poll failed, almost definitely due to timeout

      // If not, you're screwed anyway, because it probably means the kernel ran

      // out of memory.

      return false;

    }

  }

  return false;

}

// Sideload service always exits after serving an install command.

static void SideloadHostService(unique_fd sfd, const std::string& args) {

  using namespace std::chrono_literals;

  MinadbdCommandStatus status;

  exit(RunAdbFuseSideload(sfd.get(), args, &status));

  auto error = RunAdbFuseSideload(sfd.get(), args, &status);

  // No need to wait if the socket is already closed, meaning the other end

  // already exited for some reason.

  if (error != kMinadbdHostSocketIOError) {

    // We sleep for a little bit just to wait for the host to receive last

    // "DONEDONE" message. However minadbd process is likely to get terminated

    // early due to exit_on_close

    WaitForSocketClose(sfd, 3000ms);

  }

  exit(error);

}

// Rescue service waits for the next command after an install command.