@startuml
skinparam dpi 300
skinparam ArrowFontSize 18

start

repeat
	: Receive single byte;
    if( read successful? ) then (yes)
    	repeat
     		: Get rest of packet;
            note left: Retry zero byte reads for maximum period \nof **MQTT_RECV_POLLING_TIMEOUT_MS**
        repeat while( Received complete packet? ) is ( no )
    	: Deserialize packet;
        if ( Need to send ACK response? ) then (yes)
            repeat
            	: Send ACK packet;
                note left: Retry zero byte sends for maximum period \nof **MQTT_SEND_RETRY_TIMEOUT_MS**
            repeat while( Sent complete packet? ) is ( no )
        else (no)
        endif
    else (no)
    endif

repeat while (**timeout** reached) is (no)
-> yes or timeout == 0;

stop

@enduml