text: /*
   * FreeRTOS Kernel V10.0.1
   * 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.
   *
   * http://aws.amazon.com/freertos
   * http://www.FreeRTOS.org
   */
  
  
  /*****************************************************************************
  *
  * See the following URL for configuration information.
  * http://www.freertos.org/FreeRTOS-Plus/FreeRTOS_Plus_TCP/TCP_IP_Configuration.html
  *
  *****************************************************************************/
  #ifndef FREERTOS_IP_CONFIG_H
  #define FREERTOS_IP_CONFIG_H
  
  /* Set to 1 to print out debug messages.  If ipconfigHAS_DEBUG_PRINTF is set to
   * 1 then FreeRTOS_debug_printf should be defined to the function used to print
   * out the debugging messages. */
  #define ipconfigHAS_DEBUG_PRINTF    0
  #if ( ipconfigHAS_DEBUG_PRINTF == 1 )
      #define FreeRTOS_debug_printf( X )    configPRINTF( X )
  #endif
  
  /* Set to 1 to print out non debugging messages, for example the output of the
   * FreeRTOS_netstat() command, and ping replies.  If ipconfigHAS_PRINTF is set to 1
   * then FreeRTOS_printf should be set to the function used to print out the
   * messages. */
  #define ipconfigHAS_PRINTF    1
  #if ( ipconfigHAS_PRINTF == 1 )
      #define FreeRTOS_printf( X )    configPRINTF( X )
  #endif
  
  /* Define the byte order of the target MCU (the MCU FreeRTOS+TCP is executing
   * on).  Valid options are pdFREERTOS_BIG_ENDIAN and pdFREERTOS_LITTLE_ENDIAN. */
  #define ipconfigBYTE_ORDER                         pdFREERTOS_LITTLE_ENDIAN        
  
  /* If the network card/driver includes checksum offloading (IP/TCP/UDP checksums)
   * then set ipconfigDRIVER_INCLUDED_RX_IP_CHECKSUM to 1 to prevent the software
   * stack repeating the checksum calculations. */
  #define ipconfigDRIVER_INCLUDED_RX_IP_CHECKSUM     1
  
  /* Several API's will block until the result is known, or the action has been
   * performed, for example FreeRTOS_send() and FreeRTOS_recv().  The timeouts can be
   * set per socket, using setsockopt().  If not set, the times below will be
   * used as defaults. */
  #define ipconfigSOCK_DEFAULT_RECEIVE_BLOCK_TIME    (10000)
  #define ipconfigSOCK_DEFAULT_SEND_BLOCK_TIME       (10000)
  
  /* Include support for DNS caching.  For TCP, having a small DNS cache is very
   * useful.  When a cache is present, ipconfigDNS_REQUEST_ATTEMPTS can be kept low
   * and also DNS may use small timeouts.  If a DNS reply comes in after the DNS
   * socket has been destroyed, the result will be stored into the cache.  The next
   * call to FreeRTOS_gethostbyname() will return immediately, without even creating
   * a socket. */
  #define ipconfigUSE_DNS_CACHE                      (1)
  #define ipconfigDNS_REQUEST_ATTEMPTS               (2)
  
  /* The IP stack executes it its own task (although any application task can make
   * use of its services through the published sockets API). ipconfigUDP_TASK_PRIORITY
   * sets the priority of the task that executes the IP stack.  The priority is a
   * standard FreeRTOS task priority so can take any value from 0 (the lowest
   * priority) to (configMAX_PRIORITIES - 1) (the highest priority).
   * configMAX_PRIORITIES is a standard FreeRTOS configuration parameter defined in
   * FreeRTOSConfig.h, not FreeRTOSIPConfig.h. Consideration needs to be given as to
   * the priority assigned to the task executing the IP stack relative to the
   * priority assigned to tasks that use the IP stack. */
  #define ipconfigIP_TASK_PRIORITY                   (configMAX_PRIORITIES - 2)
  
  /* The size, in words (not bytes), of the stack allocated to the FreeRTOS+TCP
   * task.  This setting is less important when the FreeRTOS Win32 simulator is used
   * as the Win32 simulator only stores a fixed amount of information on the task
   * stack.  FreeRTOS includes optional stack overflow detection, see:
   * http://www.freertos.org/Stacks-and-stack-overflow-checking.html. */
  #define ipconfigIP_TASK_STACK_SIZE_WORDS           (configMINIMAL_STACK_SIZE * 5)
  
  /* ipconfigRAND32() is called by the IP stack to generate random numbers for
   * things such as a DHCP transaction number or initial sequence number.  Random
   * number generation is performed via this macro to allow applications to use their
   * own random number generation method.  For example, it might be possible to
   * generate a random number by sampling noise on an analogue input. */
  uint32_t ulRand(void);
  #define ipconfigRAND32()    ulRand()
  
  /* If ipconfigUSE_NETWORK_EVENT_HOOK is set to 1 then FreeRTOS+TCP will call the
   * network event hook at the appropriate times.  If ipconfigUSE_NETWORK_EVENT_HOOK
   * is not set to 1 then the network event hook will never be called. See:
   * http://www.FreeRTOS.org/FreeRTOS-Plus/FreeRTOS_Plus_UDP/API/vApplicationIPNetworkEventHook.shtml.
   */
  #define ipconfigUSE_NETWORK_EVENT_HOOK           1
  
  /* Sockets have a send block time attribute.  If FreeRTOS_sendto() is called but
   * a network buffer cannot be obtained then the calling task is held in the Blocked
   * state (so other tasks can continue to executed) until either a network buffer
   * becomes available or the send block time expires.  If the send block time expires
   * then the send operation is aborted.  The maximum allowable send block time is
   * capped to the value set by ipconfigMAX_SEND_BLOCK_TIME_TICKS.  Capping the
   * maximum allowable send block time prevents prevents a deadlock occurring when
   * all the network buffers are in use and the tasks that process (and subsequently
   * free) the network buffers are themselves blocked waiting for a network buffer.
   * ipconfigMAX_SEND_BLOCK_TIME_TICKS is specified in RTOS ticks.  A time in
   * milliseconds can be converted to a time in ticks by dividing the time in
   * milliseconds by portTICK_PERIOD_MS. */
  #define ipconfigUDP_MAX_SEND_BLOCK_TIME_TICKS    (5000 / portTICK_PERIOD_MS)
  
  /* If ipconfigUSE_DHCP is 1 then FreeRTOS+TCP will attempt to retrieve an IP
   * address, netmask, DNS server address and gateway address from a DHCP server.  If
   * ipconfigUSE_DHCP is 0 then FreeRTOS+TCP will use a static IP address.  The
   * stack will revert to using the static IP address even when ipconfigUSE_DHCP is
   * set to 1 if a valid configuration cannot be obtained from a DHCP server for any
   * reason.  The static configuration used is that passed into the stack by the
   * FreeRTOS_IPInit() function call. */
  #define ipconfigUSE_DHCP                         1
  #define ipconfigDHCP_REGISTER_HOSTNAME           1
  #define ipconfigDHCP_USES_UNICAST                1
  #define ipconfigDHCP_SEND_DISCOVER_AFTER_AUTO_IP 0
  
  /* If ipconfigDHCP_USES_USER_HOOK is set to 1 then the application writer must
   * provide an implementation of the DHCP callback function,
   * xApplicationDHCPUserHook(). */
  #define ipconfigUSE_DHCP_HOOK                    0
  
  /* When ipconfigUSE_DHCP is set to 1, DHCP requests will be sent out at
   * increasing time intervals until either a reply is received from a DHCP server
   * and accepted, or the interval between transmissions reaches
   * ipconfigMAXIMUM_DISCOVER_TX_PERIOD.  The IP stack will revert to using the
   * static IP address passed as a parameter to FreeRTOS_IPInit() if the
   * re-transmission time interval reaches ipconfigMAXIMUM_DISCOVER_TX_PERIOD without
   * a DHCP reply being received. */
  #define ipconfigMAXIMUM_DISCOVER_TX_PERIOD     (120000 / portTICK_PERIOD_MS)
  
  /* The ARP cache is a table that maps IP addresses to MAC addresses.  The IP
   * stack can only send a UDP message to a remove IP address if it knowns the MAC
   * address associated with the IP address, or the MAC address of the router used to
   * contact the remote IP address.  When a UDP message is received from a remote IP
   * address the MAC address and IP address are added to the ARP cache.  When a UDP
   * message is sent to a remote IP address that does not already appear in the ARP
   * cache then the UDP message is replaced by a ARP message that solicits the
   * required MAC address information.  ipconfigARP_CACHE_ENTRIES defines the maximum
   * number of entries that can exist in the ARP table at any one time. */
  #define ipconfigARP_CACHE_ENTRIES                 6
  
  /* ARP requests that do not result in an ARP response will be re-transmitted a
   * maximum of ipconfigMAX_ARP_RETRANSMISSIONS times before the ARP request is
   * aborted. */
  #define ipconfigMAX_ARP_RETRANSMISSIONS           (5)
  
  /* ipconfigMAX_ARP_AGE defines the maximum time between an entry in the ARP
   * table being created or refreshed and the entry being removed because it is stale.
   * New ARP requests are sent for ARP cache entries that are nearing their maximum
   * age.  ipconfigMAX_ARP_AGE is specified in tens of seconds, so a value of 150 is
   * equal to 1500 seconds (or 25 minutes). */
  #define ipconfigMAX_ARP_AGE                       150
  
  /* Implementing FreeRTOS_inet_addr() necessitates the use of string handling
   * routines, which are relatively large.  To save code space the full
   * FreeRTOS_inet_addr() implementation is made optional, and a smaller and faster
   * alternative called FreeRTOS_inet_addr_quick() is provided.  FreeRTOS_inet_addr()
   * takes an IP in decimal dot format (for example, "192.168.0.1") as its parameter.
   * FreeRTOS_inet_addr_quick() takes an IP address as four separate numerical octets
   * (for example, 192, 168, 0, 1) as its parameters.  If
   * ipconfigINCLUDE_FULL_INET_ADDR is set to 1 then both FreeRTOS_inet_addr() and
   * FreeRTOS_indet_addr_quick() are available.  If ipconfigINCLUDE_FULL_INET_ADDR is
   * not set to 1 then only FreeRTOS_indet_addr_quick() is available. */
  #define ipconfigINCLUDE_FULL_INET_ADDR            0
  
  /* ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS defines the total number of network buffer that
   * are available to the IP stack.  The total number of network buffers is limited
   * to ensure the total amount of RAM that can be consumed by the IP stack is capped
   * to a pre-determinable value. */
  #define ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS    ETHER_CFG_EMAC_TX_DESCRIPTORS
  
  /* A FreeRTOS queue is used to send events from application tasks to the IP
   * stack.  ipconfigEVENT_QUEUE_LENGTH sets the maximum number of events that can
   * be queued for processing at any one time.  The event queue must be a minimum of
   * 5 greater than the total number of network buffers. */
  #define ipconfigEVENT_QUEUE_LENGTH     (ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS + 5)
  
  /* The address of a socket is the combination of its IP address and its port
   * number.  FreeRTOS_bind() is used to manually allocate a port number to a socket
   * (to 'bind' the socket to a port), but manual binding is not normally necessary
   * for client sockets (those sockets that initiate outgoing connections rather than
   * wait for incoming connections on a known port number).  If
   * ipconfigALLOW_SOCKET_SEND_WITHOUT_BIND is set to 1 then calling
   * FreeRTOS_sendto() on a socket that has not yet been bound will result in the IP
   * stack automatically binding the socket to a port number from the range
   * socketAUTO_PORT_ALLOCATION_START_NUMBER to 0xffff.  If
   * ipconfigALLOW_SOCKET_SEND_WITHOUT_BIND is set to 0 then calling FreeRTOS_sendto()
   * on a socket that has not yet been bound will result in the send operation being
   * aborted. */
  #define ipconfigALLOW_SOCKET_SEND_WITHOUT_BIND         1
  
  /* Defines the Time To Live (TTL) values used in outgoing UDP packets. */
  #define ipconfigUDP_TIME_TO_LIVE                       128
  /* Also defined in FreeRTOSIPConfigDefaults.h. */
  #define ipconfigTCP_TIME_TO_LIVE                       128
  
  /* USE_TCP: Use TCP and all its features. */
  #define ipconfigUSE_TCP                                (1)
  
  /* USE_WIN: Let TCP use windowing mechanism. */
  #define ipconfigUSE_TCP_WIN                            (1)
  
  /* The MTU is the maximum number of bytes the payload of a network frame can
   * contain.  For normal Ethernet V2 frames the maximum MTU is 1500.  Setting a
   * lower value can save RAM, depending on the buffer management scheme used.  If
   * ipconfigCAN_FRAGMENT_OUTGOING_PACKETS is 1 then (ipconfigNETWORK_MTU - 28) must
   * be divisible by 8. */
  #define ipconfigNETWORK_MTU                            1500
  
  /* Set ipconfigUSE_DNS to 1 to include a basic DNS client/resolver.  DNS is used
   * through the FreeRTOS_gethostbyname() API function. */
  #define ipconfigUSE_DNS                                1
  
  /* If ipconfigREPLY_TO_INCOMING_PINGS is set to 1 then the IP stack will
   * generate replies to incoming ICMP echo (ping) requests. */
  #define ipconfigREPLY_TO_INCOMING_PINGS                1
  
  /* If ipconfigSUPPORT_OUTGOING_PINGS is set to 1 then the
   * FreeRTOS_SendPingRequest() API function is available. */
  #define ipconfigSUPPORT_OUTGOING_PINGS                 0
  
  /* If ipconfigSUPPORT_SELECT_FUNCTION is set to 1 then the FreeRTOS_select()
   * (and associated) API function is available. */
  #define ipconfigSUPPORT_SELECT_FUNCTION                0
  
  /* If ipconfigFILTER_OUT_NON_ETHERNET_II_FRAMES is set to 1 then Ethernet frames
   * that are not in Ethernet II format will be dropped.  This option is included for
   * potential future IP stack developments. */
  #define ipconfigFILTER_OUT_NON_ETHERNET_II_FRAMES      1
  
  /* If ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES is set to 1 then it is the
   * responsibility of the Ethernet interface to filter out packets that are of no
   * interest.  If the Ethernet interface does not implement this functionality, then
   * set ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES to 0 to have the IP stack
   * perform the filtering instead (it is much less efficient for the stack to do it
   * because the packet will already have been passed into the stack).  If the
   * Ethernet driver does all the necessary filtering in hardware then software
   * filtering can be removed by using a value other than 1 or 0. */
  #define ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES    0 //XXX
  
  /* The windows simulator cannot really simulate MAC interrupts, and needs to
   * block occasionally to allow other tasks to run. */
  //#define configWINDOWS_MAC_INTERRUPT_SIMULATOR_DELAY    ( 20 / portTICK_PERIOD_MS )
  
  /* Advanced only: in order to access 32-bit fields in the IP packets with
   * 32-bit memory instructions, all packets will be stored 32-bit-aligned,
   * plus 16-bits. This has to do with the contents of the IP-packets: all
   * 32-bit fields are 32-bit-aligned, plus 16-bit. */
  #define ipconfigPACKET_FILLER_SIZE                     2
  
  /* Define the size of the pool of TCP window descriptors.  On the average, each
   * TCP socket will use up to 2 x 6 descriptors, meaning that it can have 2 x 6
   * outstanding packets (for Rx and Tx).  When using up to 10 TP sockets
   * simultaneously, one could define TCP_WIN_SEG_COUNT as 120. */
  #define ipconfigTCP_WIN_SEG_COUNT                      240
  
  /* Each TCP socket has a circular buffers for Rx and Tx, which have a fixed
   * maximum size.  Define the size of Rx buffer for TCP sockets. */
  #define ipconfigTCP_RX_BUFFER_LENGTH                   (3000)
  
  /* Define the size of Tx buffer for TCP sockets. */
  #define ipconfigTCP_TX_BUFFER_LENGTH                   (3000)
  
  /* When using call-back handlers, the driver may check if the handler points to
   * real program memory (RAM or flash) or just has a random non-zero value. */
  #define ipconfigIS_VALID_PROG_ADDRESS( x )    ( ( x ) != NULL )
  
  /* Include support for TCP keep-alive messages. */
  #define ipconfigTCP_KEEP_ALIVE                   (1)
  #define ipconfigTCP_KEEP_ALIVE_INTERVAL          (20) /* Seconds. */
  
  /* The socket semaphore is used to unblock the MQTT task. */
  #define ipconfigSOCKET_HAS_USER_SEMAPHORE        (0)
  
  #define ipconfigSOCKET_HAS_USER_WAKE_CALLBACK    (1)
  #define ipconfigUSE_CALLBACKS                    (0)
  
  #define ipconfigZERO_COPY_TX_DRIVER              (0)
  #define ipconfigZERO_COPY_RX_DRIVER              (0)
  
  /* Possible optimisation for expert users - requires network driver support.
   * When ipconfigUSE_LINKED_RX_MESSAGES is set to non-zero value then
   * instead of passing received packets into the IP task one at a time the
   * network interface can chain received packets together and pass them into
   * the IP task in one go.  The packets are chained using the pxNextBuffer
   * member. This optimisation is useful when there is high network traffic.
   * When ipconfigUSE_LINKED_RX_MESSAGES is set to 0 then only one buffer will
   * be sent at a time.  This is the default way for +TCP to pass messages from
   * the MAC to the TCP/IP stack. */
  #define ipconfigUSE_LINKED_RX_MESSAGES           (0)
  
  #define portINLINE                               __inline
  
  void vApplicationMQTTGetKeys( const char ** ppcRootCA,
                                const char ** ppcClientCert,
                                const char ** ppcClientPrivateKey );
  
  #endif /* FREERTOS_IP_CONFIG_H */
  