map/das-dn/third_party/mqtt/handle_pubrel.c

/*
Copyright (c) 2009-2020 Roger Light <roger@atchoo.org>

All rights reserved. This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
and Eclipse Distribution License v1.0 which accompany this distribution.

The Eclipse Public License is available at
   https://www.eclipse.org/legal/epl-2.0/
and the Eclipse Distribution License is available at
  http://www.eclipse.org/org/documents/edl-v10.php.

SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause

Contributors:
   Roger Light - initial implementation and documentation.
*/

#include "config.h"

#include <assert.h>
#include <stdio.h>
#include <string.h>

#include "mosquitto.h"
#include "logging_mosq.h"
#include "memory_mosq.h"
#include "messages_mosq.h"
#include "mqtt_protocol.h"
#include "net_mosq.h"
#include "packet_mosq.h"
#include "read_handle.h"
#include "send_mosq.h"
#include "util_mosq.h"


int handle__pubrel(struct mosquitto *mosq)
{
	uint8_t reason_code;
	uint16_t mid;

	struct mosquitto_message_all *message = NULL;

	int rc;
	mosquitto_property *properties = NULL;

	assert(mosq);

	if (mosquitto__get_state(mosq) != mosq_cs_active)
	{
		return MOSQ_ERR_PROTOCOL;
	}
	if (mosq->protocol != mosq_p_mqtt31 && mosq->in_packet.command != (CMD_PUBREL|2))
	{
		return MOSQ_ERR_MALFORMED_PACKET;
	}

	if (mosq->protocol != mosq_p_mqtt31)
	{
		if ((mosq->in_packet.command&0x0F) != 0x02)
		{
			return MOSQ_ERR_PROTOCOL;
		}
	}
	rc = packet__read_uint16(&mosq->in_packet, &mid);
	if (rc) return rc;
	if (mid == 0) return MOSQ_ERR_PROTOCOL;

	if (mosq->protocol == mosq_p_mqtt5 && mosq->in_packet.remaining_length > 2)
	{
		rc = packet__read_byte(&mosq->in_packet, &reason_code);
		if (rc) return rc;

		if (reason_code != MQTT_RC_SUCCESS && reason_code != MQTT_RC_PACKET_ID_NOT_FOUND)
		{
			return MOSQ_ERR_PROTOCOL;
		}

		if (mosq->in_packet.remaining_length > 3)
		{
			rc = property__read_all(CMD_PUBREL, &mosq->in_packet, &properties);
			if (rc) return rc;
		}
	}

	if (mosq->in_packet.pos < mosq->in_packet.remaining_length)
	{
		return MOSQ_ERR_MALFORMED_PACKET;
	}

	log__printf(mosq, MOSQ_LOG_DEBUG, "Client %s received PUBREL (Mid: %d)", SAFE_PRINT(mosq->id), mid);

	rc = send__pubcomp(mosq, mid, NULL);
	if (rc)
	{
		message__remove(mosq, mid, mosq_md_in, &message, 2);
		return rc;
	}

	rc = message__remove(mosq, mid, mosq_md_in, &message, 2);
	if (rc == MOSQ_ERR_SUCCESS)
	{
		/* Only pass the message on if we have removed it from the queue - this
		 * prevents multiple callbacks for the same message. */
		pthread_mutex_lock(&mosq->callback_mutex);
		if (mosq->on_message)
		{
			mosq->in_callback = true;
			mosq->on_message(mosq, mosq->userdata, &message->msg);
			mosq->in_callback = false;
		}
		if (mosq->on_message_v5)
		{
			mosq->in_callback = true;
			mosq->on_message_v5(mosq, mosq->userdata, &message->msg, message->properties);
			mosq->in_callback = false;
		}
		pthread_mutex_unlock(&mosq->callback_mutex);
		mosquitto_property_free_all(&properties);
		message__cleanup(&message);
	}
	else if (rc == MOSQ_ERR_NOT_FOUND)
	{
		return MOSQ_ERR_SUCCESS;
	}
	else
	{
		return rc;
	}

	return MOSQ_ERR_SUCCESS;
}