chpp/services/loopback.c

/*
 * Copyright (C) 2020 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "chpp/services/loopback.h"

#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>

#include "chpp/app.h"
#include "chpp/memory.h"
#include "chpp/platform/log.h"
#include "chpp/transport.h"

/************************************************
 *  Public Functions
 ***********************************************/

bool chppDispatchLoopbackClientRequest(struct ChppAppState *context,
                                       uint8_t *buf, size_t len) {
  uint8_t *response = chppMalloc(len);
  if (response == NULL) {
    CHPP_LOG_OOM("Loopback response of %" PRIuSIZE " bytes", len);
    chppEnqueueTxErrorDatagram(context->transportContext,
                               CHPP_TRANSPORT_ERROR_OOM);

  } else {
    // Copy received datagram
    memcpy(response, buf, len);

    // Modify response message type per loopback spec.
    struct ChppAppHeader *responseHeader = (struct ChppAppHeader *)response;
    responseHeader->type = CHPP_MESSAGE_TYPE_SERVICE_RESPONSE;

    // Send out response datagram
    chppEnqueueTxDatagramOrFail(context->transportContext, response, len);
  }

  return true;
}