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/******************************************************************************
 *
 *  Copyright (C) 2003-2012 Broadcom Corporation
 *
 *  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.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  This contains constants definitions and other information from the AVCTP
 *  specification.  This file is intended for use internal to AVCT only.
 *
 ******************************************************************************/
#ifndef AVCT_DEFS_H
#define AVCT_DEFS_H

/*****************************************************************************
 * constants
 ****************************************************************************/

/* packet type */
#define AVCT_PKT_TYPE_SINGLE 0 /* single packet */
#define AVCT_PKT_TYPE_START 1  /* start packet */
#define AVCT_PKT_TYPE_CONT 2   /* continue packet */
#define AVCT_PKT_TYPE_END 3    /* end packet */

/* header lengths for different packet types */
#define AVCT_HDR_LEN_SINGLE 3
#define AVCT_HDR_LEN_START 4
#define AVCT_HDR_LEN_CONT 1
#define AVCT_HDR_LEN_END 1

/* invalid cr+ipid value */
#define AVCT_CR_IPID_INVALID 1

/*****************************************************************************
 * message parsing and building macros
 ****************************************************************************/

#define AVCT_BUILD_HDR(p, label, type, cr_ipid) \
  *(p)++ = ((label) << 4) | ((type) << 2) | (cr_ipid);

#define AVCT_PARSE_HDR(p, label, type, cr_ipid) \
  do {                                          \
    (label) = *(p) >> 4;                        \
    (type) = (*(p) >> 2) & 3;                   \
    (cr_ipid) = *(p)++ & 3;                     \
  } while (0)

#define AVCT_PKT_TYPE(p) ((*(p) >> 2) & 3)

#endif /* AVCT_DEFS_H */