zircon/system/ulib/xdc-host-utils/client.cc

// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/un.h>
#include <unistd.h>

#include <xdc-host-utils/client.h>
#include <xdc-host-utils/conn.h>

#include <utility>

namespace xdc {

zx_status_t GetStream(uint32_t stream_id, fbl::unique_fd* out_fd) {
  fbl::unique_fd fd(socket(AF_UNIX, SOCK_STREAM, 0));
  if (!fd) {
    fprintf(stderr, "Could not create socket, err: %s\n", strerror(errno));
    return ZX_ERR_IO;
  }
  // Connect to the host xdc server.
  struct sockaddr_un server = {};
  server.sun_family = AF_UNIX;
  strncpy(server.sun_path, XDC_SOCKET_PATH, sizeof(server.sun_path));
  if (connect(fd.get(), (struct sockaddr*)&server, sizeof(server)) < 0) {
    fprintf(stderr, "Could not connect to server: %s, err: %s\n", XDC_SOCKET_PATH, strerror(errno));
    return ZX_ERR_IO;
  }
  // Register the stream id.
  ssize_t n = send(fd.get(), &stream_id, sizeof(stream_id), MSG_WAITALL);
  if (n != sizeof(stream_id)) {
    fprintf(stderr, "Write failed, expected %lu written, got %ld, err: %s\n", sizeof(stream_id), n,
            strerror(errno));
    return ZX_ERR_IO;
  }
  // Wait for the server registration response.
  RegisterStreamResponse connected_resp;
  n = recv(fd.get(), &connected_resp, sizeof(connected_resp), MSG_WAITALL);
  if (n != sizeof(connected_resp)) {
    fprintf(stderr, "Read failed, expected %lu read, got %ld, err: %s\n", sizeof(connected_resp), n,
            strerror(errno));
    return ZX_ERR_IO;
  }
  if (!connected_resp) {
    fprintf(stderr, "Stream id %u was already taken, exiting\n", stream_id);
    return ZX_ERR_ALREADY_BOUND;
  }
  *out_fd = std::move(fd);
  return ZX_OK;
}

}  // namespace xdc