iot_mqtt_helper.h

/*
 * IoT MQTT V2.1.0
 * Copyright (C) 2018 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef IOT_MQTT_HELPER_H_
#define IOT_MQTT_HELPER_H_

/* Standard includes. */
#include <string.h>
#include <limits.h>
/* Default assert and memory allocation functions. */
#include <assert.h>
#include <stdlib.h>

/* MQTT Protocol Specific defines */
#include "iot_mqtt_protocol.h"
/* MQTT types include. */
#include "types/iot_mqtt_types.h"

/*-----------------------------------------------------------*/

/*
 * Macros for reading the high and low byte of a 2-byte unsigned int.
 */
#define UINT16_HIGH_BYTE( x )    ( ( uint8_t ) ( ( x ) >> 8 ) )          
#define UINT16_LOW_BYTE( x )     ( ( uint8_t ) ( ( x ) & 0x00ffU ) )     
#define UINT16_DECODE( ptr )                                \
    ( uint16_t ) ( ( ( ( uint16_t ) ( *( ptr ) ) ) << 8 ) | \
                   ( ( uint16_t ) ( *( ( ptr ) + 1 ) ) ) )

#define UINT8_SET_BIT( x, position )      ( ( x ) = ( uint8_t ) ( ( x ) | ( 0x01U << ( position ) ) ) )

#define UINT8_CHECK_BIT( x, position )    ( ( ( x ) &( 0x01U << ( position ) ) ) == ( 0x01U << ( position ) ) )

#ifndef AWS_IOT_MQTT_ENABLE_METRICS
    #define AWS_IOT_MQTT_ENABLE_METRICS    ( 1 )
#endif

/*-----------------------------------------------------------*/

size_t _IotMqtt_RemainingLengthEncodedSize( size_t length );

bool _IotMqtt_ConnectPacketSize( const IotMqttConnectInfo_t * pConnectInfo,
                                 size_t * pRemainingLength,
                                 size_t * pPacketSize );


void _IotMqtt_SerializeConnectCommon( const IotMqttConnectInfo_t * pConnectInfo,
                                      size_t remainingLength,
                                      uint8_t * pPacket,
                                      size_t connectPacketSize );

bool _IotMqtt_SubscriptionPacketSize( IotMqttOperationType_t type,
                                      const IotMqttSubscription_t * pSubscriptionList,
                                      size_t subscriptionCount,
                                      size_t * pRemainingLength,
                                      size_t * pPacketSize );

void _IotMqtt_SerializeSubscribeCommon( const IotMqttSubscription_t * pSubscriptionList,
                                        size_t subscriptionCount,
                                        size_t remainingLength,
                                        uint16_t * pPacketIdentifier,
                                        uint8_t * pPacket,
                                        size_t subscribePacketSize );

void _IotMqtt_SerializeUnsubscribeCommon( const IotMqttSubscription_t * pSubscriptionList,
                                          size_t subscriptionCount,
                                          size_t remainingLength,
                                          uint16_t * pPacketIdentifier,
                                          uint8_t * pPacket,
                                          size_t unsubscribePacketSize );

bool _IotMqtt_PublishPacketSize( const IotMqttPublishInfo_t * pPublishInfo,
                                 size_t * pRemainingLength,
                                 size_t * pPacketSize );

void _IotMqtt_SerializePublishCommon( const IotMqttPublishInfo_t * pPublishInfo,
                                      size_t remainingLength,
                                      uint16_t * pPacketIdentifier,
                                      uint8_t ** pPacketIdentifierHigh,
                                      uint8_t * pPacket,
                                      size_t publishPacketSize );

bool _IotMqtt_IncomingPacketValid( uint8_t packetType );

uint16_t _IotMqtt_NextPacketIdentifier( void );

IotMqttError_t _IotMqtt_ProcessPublishFlags( uint8_t publishFlags,
                                             IotMqttPublishInfo_t * pOutput );

#endif /* ifndef IOT_MQTT_HELPER_H_ */