Merge "tombstoned: log where we're writing the tombstone." into oc-dev

  unique_fd crash_fd;

  pid_t crash_pid;

  event* crash_event = nullptr;

  std::string crash_path;

};

static constexpr char kTombstoneDirectory[] = "/data/tombstones/";

  next_tombstone = oldest_tombstone;

}

static unique_fd get_tombstone_fd() {

static std::pair<unique_fd, std::string> get_tombstone() {

  // If kMaxConcurrentDumps is greater than 1, then theoretically the same

  // filename could be handed out to multiple processes. Unlink and create the

  // file, instead of using O_TRUNC, to avoid two processes interleaving their

  // output.

  unique_fd result;

  char buf[PATH_MAX];

  snprintf(buf, sizeof(buf), "tombstone_%02d", next_tombstone);

  if (unlinkat(tombstone_directory_fd, buf, 0) != 0 && errno != ENOENT) {

    PLOG(FATAL) << "failed to unlink tombstone at " << kTombstoneDirectory << buf;

  std::string file_name = StringPrintf("tombstone_%02d", next_tombstone);

  if (unlinkat(tombstone_directory_fd, file_name.c_str(), 0) != 0 && errno != ENOENT) {

    PLOG(FATAL) << "failed to unlink tombstone at " << kTombstoneDirectory << "/" << file_name;

  }

  result.reset(

    openat(tombstone_directory_fd, buf, O_CREAT | O_EXCL | O_WRONLY | O_APPEND | O_CLOEXEC, 0640));

  result.reset(openat(tombstone_directory_fd, file_name.c_str(),

                      O_CREAT | O_EXCL | O_WRONLY | O_APPEND | O_CLOEXEC, 0640));

  if (result == -1) {

    PLOG(FATAL) << "failed to create tombstone at " << kTombstoneDirectory << buf;

    PLOG(FATAL) << "failed to create tombstone at " << kTombstoneDirectory << "/" << file_name;

  }

  next_tombstone = (next_tombstone + 1) % kTombstoneCount;

  return result;

  return {std::move(result), std::string(kTombstoneDirectory) + "/" + file_name};

}

static void perform_request(Crash* crash) {

  unique_fd output_fd;

  if (!intercept_manager->GetIntercept(crash->crash_pid, &output_fd)) {

    output_fd = get_tombstone_fd();

    std::tie(output_fd, crash->crash_path) = get_tombstone();

  }

  TombstonedCrashPacket response = {

    goto fail;

  }

  if (!crash->crash_path.empty()) {

    LOG(ERROR) << "Tombstone written to: " << crash->crash_path;

  }

fail:

  delete crash;