--- /dev/null
+/**
+ * @file
+ *
+ * lwIP Options Configuration
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+#ifndef __LWIP_OPT_H__
+#define __LWIP_OPT_H__
+
+/*
+ * Include user defined options first. Anything not defined in these files
+ * will be set to standard values. Override anything you dont like!
+ */
+#include <lwip/lwipopts.h>
+#include "lwip/debug.h"
+
+/*
+ -----------------------------------------------
+ ---------- Platform specific locking ----------
+ -----------------------------------------------
+*/
+
+/**
+ * SYS_LIGHTWEIGHT_PROT==1: if you want inter-task protection for certain
+ * critical regions during buffer allocation, deallocation and memory
+ * allocation and deallocation.
+ */
+#ifndef SYS_LIGHTWEIGHT_PROT
+#define SYS_LIGHTWEIGHT_PROT 0
+#endif
+
+/**
+ * NO_SYS==1: Provides VERY minimal functionality. Otherwise,
+ * use lwIP facilities.
+ */
+#ifndef NO_SYS
+#define NO_SYS 0
+#endif
+
+/**
+ * MEMCPY: override this if you have a faster implementation at hand than the
+ * one included in your C library
+ */
+#ifndef MEMCPY
+#define MEMCPY(dst,src,len) memcpy(dst,src,len)
+#endif
+
+/**
+ * SMEMCPY: override this with care! Some compilers (e.g. gcc) can inline a
+ * call to memcpy() if the length is known at compile time and is small.
+ */
+#ifndef SMEMCPY
+#define SMEMCPY(dst,src,len) memcpy(dst,src,len)
+#endif
+
+/*
+ ------------------------------------
+ ---------- Memory options ----------
+ ------------------------------------
+*/
+/**
+ * MEM_LIBC_MALLOC==1: Use malloc/free/realloc provided by your C-library
+ * instead of the lwip internal allocator. Can save code size if you
+ * already use it.
+ */
+#ifndef MEM_LIBC_MALLOC
+#define MEM_LIBC_MALLOC 0
+#endif
+
+/**
+ * MEM_ALIGNMENT: should be set to the alignment of the CPU
+ * 4 byte alignment -> #define MEM_ALIGNMENT 4
+ * 2 byte alignment -> #define MEM_ALIGNMENT 2
+ */
+#ifndef MEM_ALIGNMENT
+#define MEM_ALIGNMENT 1
+#endif
+
+/**
+ * MEM_SIZE: the size of the heap memory. If the application will send
+ * a lot of data that needs to be copied, this should be set high.
+ */
+#ifndef MEM_SIZE
+#define MEM_SIZE 1600
+#endif
+
+/**
+ * MEMP_OVERFLOW_CHECK: memp overflow protection reserves a configurable
+ * amount of bytes before and after each memp element in every pool and fills
+ * it with a prominent default value.
+ * MEMP_OVERFLOW_CHECK == 0 no checking
+ * MEMP_OVERFLOW_CHECK == 1 checks each element when it is freed
+ * MEMP_OVERFLOW_CHECK >= 2 checks each element in every pool every time
+ * memp_malloc() or memp_free() is called (useful but slow!)
+ */
+#ifndef MEMP_OVERFLOW_CHECK
+#define MEMP_OVERFLOW_CHECK 0
+#endif
+
+/**
+ * MEMP_SANITY_CHECK==1: run a sanity check after each memp_free() to make
+ * sure that there are no cycles in the linked lists.
+ */
+#ifndef MEMP_SANITY_CHECK
+#define MEMP_SANITY_CHECK 0
+#endif
+
+/**
+ * MEM_USE_POOLS==1: Use an alternative to malloc() by allocating from a set
+ * of memory pools of various sizes. When mem_malloc is called, an element of
+ * the smallest pool that can provide the lenght needed is returned.
+ */
+#ifndef MEM_USE_POOLS
+#define MEM_USE_POOLS 0
+#endif
+
+/**
+ * MEMP_USE_CUSTOM_POOLS==1: whether to include a user file lwippools.h
+ * that defines additional pools beyond the "standard" ones required
+ * by lwIP. If you set this to 1, you must have lwippools.h in your
+ * inlude path somewhere.
+ */
+#ifndef MEMP_USE_CUSTOM_POOLS
+#define MEMP_USE_CUSTOM_POOLS 0
+#endif
+
+
+/*
+ ------------------------------------------------
+ ---------- Internal Memory Pool Sizes ----------
+ ------------------------------------------------
+*/
+/**
+ * MEMP_NUM_PBUF: the number of memp struct pbufs (used for PBUF_ROM and PBUF_REF).
+ * If the application sends a lot of data out of ROM (or other static memory),
+ * this should be set high.
+ */
+#ifndef MEMP_NUM_PBUF
+#define MEMP_NUM_PBUF 16
+#endif
+
+/**
+ * MEMP_NUM_RAW_PCB: Number of raw connection PCBs
+ * (requires the LWIP_RAW option)
+ */
+#ifndef MEMP_NUM_RAW_PCB
+#define MEMP_NUM_RAW_PCB 4
+#endif
+
+/**
+ * MEMP_NUM_UDP_PCB: the number of UDP protocol control blocks. One
+ * per active UDP "connection".
+ * (requires the LWIP_UDP option)
+ */
+#ifndef MEMP_NUM_UDP_PCB
+#define MEMP_NUM_UDP_PCB 4
+#endif
+
+/**
+ * MEMP_NUM_TCP_PCB: the number of simulatenously active TCP connections.
+ * (requires the LWIP_TCP option)
+ */
+#ifndef MEMP_NUM_TCP_PCB
+#define MEMP_NUM_TCP_PCB 5
+#endif
+
+/**
+ * MEMP_NUM_TCP_PCB_LISTEN: the number of listening TCP connections.
+ * (requires the LWIP_TCP option)
+ */
+#ifndef MEMP_NUM_TCP_PCB_LISTEN
+#define MEMP_NUM_TCP_PCB_LISTEN 8
+#endif
+
+/**
+ * MEMP_NUM_TCP_SEG: the number of simultaneously queued TCP segments.
+ * (requires the LWIP_TCP option)
+ */
+#ifndef MEMP_NUM_TCP_SEG
+#define MEMP_NUM_TCP_SEG 16
+#endif
+
+/**
+ * MEMP_NUM_REASSDATA: the number of simultaneously IP packets queued for
+ * reassembly (whole packets, not fragments!)
+ */
+#ifndef MEMP_NUM_REASSDATA
+#define MEMP_NUM_REASSDATA 5
+#endif
+
+/**
+ * MEMP_NUM_ARP_QUEUE: the number of simulateously queued outgoing
+ * packets (pbufs) that are waiting for an ARP request (to resolve
+ * their destination address) to finish.
+ * (requires the ARP_QUEUEING option)
+ */
+#ifndef MEMP_NUM_ARP_QUEUE
+#define MEMP_NUM_ARP_QUEUE 30
+#endif
+
+/**
+ * MEMP_NUM_IGMP_GROUP: The number of multicast groups whose network interfaces
+ * can be members et the same time (one per netif - allsystems group -, plus one
+ * per netif membership).
+ * (requires the LWIP_IGMP option)
+ */
+#ifndef MEMP_NUM_IGMP_GROUP
+#define MEMP_NUM_IGMP_GROUP 8
+#endif
+
+/**
+ * MEMP_NUM_SYS_TIMEOUT: the number of simulateously active timeouts.
+ * (requires NO_SYS==0)
+ */
+#ifndef MEMP_NUM_SYS_TIMEOUT
+#define MEMP_NUM_SYS_TIMEOUT 3
+#endif
+
+/**
+ * MEMP_NUM_NETBUF: the number of struct netbufs.
+ * (only needed if you use the sequential API, like api_lib.c)
+ */
+#ifndef MEMP_NUM_NETBUF
+#define MEMP_NUM_NETBUF 2
+#endif
+
+/**
+ * MEMP_NUM_NETCONN: the number of struct netconns.
+ * (only needed if you use the sequential API, like api_lib.c)
+ */
+#ifndef MEMP_NUM_NETCONN
+#define MEMP_NUM_NETCONN 4
+#endif
+
+/**
+ * MEMP_NUM_TCPIP_MSG_API: the number of struct tcpip_msg, which are used
+ * for callback/timeout API communication.
+ * (only needed if you use tcpip.c)
+ */
+#ifndef MEMP_NUM_TCPIP_MSG_API
+#define MEMP_NUM_TCPIP_MSG_API 8
+#endif
+
+/**
+ * MEMP_NUM_TCPIP_MSG_INPKT: the number of struct tcpip_msg, which are used
+ * for incoming packets.
+ * (only needed if you use tcpip.c)
+ */
+#ifndef MEMP_NUM_TCPIP_MSG_INPKT
+#define MEMP_NUM_TCPIP_MSG_INPKT 8
+#endif
+
+/**
+ * PBUF_POOL_SIZE: the number of buffers in the pbuf pool.
+ */
+#ifndef PBUF_POOL_SIZE
+#define PBUF_POOL_SIZE 16
+#endif
+
+/*
+ ---------------------------------
+ ---------- ARP options ----------
+ ---------------------------------
+*/
+/**
+ * LWIP_ARP==1: Enable ARP functionality.
+ */
+#ifndef LWIP_ARP
+#define LWIP_ARP 1
+#endif
+
+/**
+ * ARP_TABLE_SIZE: Number of active MAC-IP address pairs cached.
+ */
+#ifndef ARP_TABLE_SIZE
+#define ARP_TABLE_SIZE 10
+#endif
+
+/**
+ * ARP_QUEUEING==1: Outgoing packets are queued during hardware address
+ * resolution.
+ */
+#ifndef ARP_QUEUEING
+#define ARP_QUEUEING 1
+#endif
+
+/**
+ * ETHARP_TRUST_IP_MAC==1: Incoming IP packets cause the ARP table to be
+ * updated with the source MAC and IP addresses supplied in the packet.
+ * You may want to disable this if you do not trust LAN peers to have the
+ * correct addresses, or as a limited approach to attempt to handle
+ * spoofing. If disabled, lwIP will need to make a new ARP request if
+ * the peer is not already in the ARP table, adding a little latency.
+ */
+#ifndef ETHARP_TRUST_IP_MAC
+#define ETHARP_TRUST_IP_MAC 1
+#endif
+
+/*
+ --------------------------------
+ ---------- IP options ----------
+ --------------------------------
+*/
+/**
+ * IP_FORWARD==1: Enables the ability to forward IP packets across network
+ * interfaces. If you are going to run lwIP on a device with only one network
+ * interface, define this to 0.
+ */
+#ifndef IP_FORWARD
+#define IP_FORWARD 0
+#endif
+
+/**
+ * IP_OPTIONS_ALLOWED: Defines the behavior for IP options.
+ * IP_OPTIONS_ALLOWED==0: All packets with IP options are dropped.
+ * IP_OPTIONS_ALLOWED==1: IP options are allowed (but not parsed).
+ */
+#ifndef IP_OPTIONS_ALLOWED
+#define IP_OPTIONS_ALLOWED 1
+#endif
+
+/**
+ * IP_REASSEMBLY==1: Reassemble incoming fragmented IP packets. Note that
+ * this option does not affect outgoing packet sizes, which can be controlled
+ * via IP_FRAG.
+ */
+#ifndef IP_REASSEMBLY
+#define IP_REASSEMBLY 1
+#endif
+
+/**
+ * IP_FRAG==1: Fragment outgoing IP packets if their size exceeds MTU. Note
+ * that this option does not affect incoming packet sizes, which can be
+ * controlled via IP_REASSEMBLY.
+ */
+#ifndef IP_FRAG
+#define IP_FRAG 1
+#endif
+
+/**
+ * IP_REASS_MAXAGE: Maximum time (in multiples of IP_TMR_INTERVAL - so seconds, normally)
+ * a fragmented IP packet waits for all fragments to arrive. If not all fragments arrived
+ * in this time, the whole packet is discarded.
+ */
+#ifndef IP_REASS_MAXAGE
+#define IP_REASS_MAXAGE 3
+#endif
+
+/**
+ * IP_REASS_MAX_PBUFS: Total maximum amount of pbufs waiting to be reassembled.
+ * Since the received pbufs are enqueued, be sure to configure
+ * PBUF_POOL_SIZE > IP_REASS_MAX_PBUFS so that the stack is still able to receive
+ * packets even if the maximum amount of fragments is enqueued for reassembly!
+ */
+#ifndef IP_REASS_MAX_PBUFS
+#define IP_REASS_MAX_PBUFS 10
+#endif
+
+/**
+ * IP_FRAG_USES_STATIC_BUF==1: Use a static MTU-sized buffer for IP
+ * fragmentation. Otherwise pbufs are allocated and reference the original
+ * packet data to be fragmented.
+ */
+#ifndef IP_FRAG_USES_STATIC_BUF
+#define IP_FRAG_USES_STATIC_BUF 1
+#endif
+
+/**
+ * IP_FRAG_MAX_MTU: Assumed max MTU on any interface for IP frag buffer
+ * (requires IP_FRAG_USES_STATIC_BUF==1)
+ */
+#if IP_FRAG_USES_STATIC_BUF && !defined(IP_FRAG_MAX_MTU)
+#define IP_FRAG_MAX_MTU 1500
+#endif
+
+/**
+ * IP_DEFAULT_TTL: Default value for Time-To-Live used by transport layers.
+ */
+#ifndef IP_DEFAULT_TTL
+#define IP_DEFAULT_TTL 255
+#endif
+
+/*
+ ----------------------------------
+ ---------- ICMP options ----------
+ ----------------------------------
+*/
+/**
+ * LWIP_ICMP==1: Enable ICMP module inside the IP stack.
+ * Be careful, disable that make your product non-compliant to RFC1122
+ */
+#ifndef LWIP_ICMP
+#define LWIP_ICMP 1
+#endif
+
+/**
+ * ICMP_TTL: Default value for Time-To-Live used by ICMP packets.
+ */
+#ifndef ICMP_TTL
+#define ICMP_TTL (IP_DEFAULT_TTL)
+#endif
+
+/*
+ ---------------------------------
+ ---------- RAW options ----------
+ ---------------------------------
+*/
+/**
+ * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
+ */
+#ifndef LWIP_RAW
+#define LWIP_RAW 1
+#endif
+
+/**
+ * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
+ */
+#ifndef RAW_TTL
+#define RAW_TTL (IP_DEFAULT_TTL)
+#endif
+
+/*
+ ----------------------------------
+ ---------- DHCP options ----------
+ ----------------------------------
+*/
+/**
+ * LWIP_DHCP==1: Enable DHCP module.
+ */
+#ifndef LWIP_DHCP
+#define LWIP_DHCP 0
+#endif
+
+/**
+ * DHCP_DOES_ARP_CHECK==1: Do an ARP check on the offered address.
+ */
+#ifndef DHCP_DOES_ARP_CHECK
+#define DHCP_DOES_ARP_CHECK ((LWIP_DHCP) && (LWIP_ARP))
+#endif
+
+/*
+ ------------------------------------
+ ---------- AUTOIP options ----------
+ ------------------------------------
+*/
+/**
+ * LWIP_AUTOIP==1: Enable AUTOIP module.
+ */
+#ifndef LWIP_AUTOIP
+#define LWIP_AUTOIP 0
+#endif
+
+/**
+ * LWIP_DHCP_AUTOIP_COOP==1: Allow DHCP and AUTOIP to be both enabled on
+ * the same interface at the same time.
+ */
+#ifndef LWIP_DHCP_AUTOIP_COOP
+#define LWIP_DHCP_AUTOIP_COOP 0
+#endif
+
+/*
+ ----------------------------------
+ ---------- SNMP options ----------
+ ----------------------------------
+*/
+/**
+ * LWIP_SNMP==1: Turn on SNMP module. UDP must be available for SNMP
+ * transport.
+ */
+#ifndef LWIP_SNMP
+#define LWIP_SNMP 0
+#endif
+
+/**
+ * SNMP_CONCURRENT_REQUESTS: Number of concurrent requests the module will
+ * allow. At least one request buffer is required.
+ */
+#ifndef SNMP_CONCURRENT_REQUESTS
+#define SNMP_CONCURRENT_REQUESTS 1
+#endif
+
+/**
+ * SNMP_TRAP_DESTINATIONS: Number of trap destinations. At least one trap
+ * destination is required
+ */
+#ifndef SNMP_TRAP_DESTINATIONS
+#define SNMP_TRAP_DESTINATIONS 1
+#endif
+
+/**
+ * SNMP_PRIVATE_MIB:
+ */
+#ifndef SNMP_PRIVATE_MIB
+#define SNMP_PRIVATE_MIB 0
+#endif
+
+/**
+ * Only allow SNMP write actions that are 'safe' (e.g. disabeling netifs is not
+ * a safe action and disabled when SNMP_SAFE_REQUESTS = 1).
+ * Unsafe requests are disabled by default!
+ */
+#ifndef SNMP_SAFE_REQUESTS
+#define SNMP_SAFE_REQUESTS 1
+#endif
+
+/*
+ ----------------------------------
+ ---------- IGMP options ----------
+ ----------------------------------
+*/
+/**
+ * LWIP_IGMP==1: Turn on IGMP module.
+ */
+#ifndef LWIP_IGMP
+#define LWIP_IGMP 0
+#endif
+
+/*
+ ----------------------------------
+ ---------- DNS options -----------
+ ----------------------------------
+*/
+/**
+ * LWIP_DNS==1: Turn on DNS module. UDP must be available for DNS
+ * transport.
+ */
+#ifndef LWIP_DNS
+#define LWIP_DNS 0
+#endif
+
+/** DNS maximum number of entries to maintain locally. */
+#ifndef DNS_TABLE_SIZE
+#define DNS_TABLE_SIZE 4
+#endif
+
+/** DNS maximum host name length supported in the name table. */
+#ifndef DNS_MAX_NAME_LENGTH
+#define DNS_MAX_NAME_LENGTH 256
+#endif
+
+/** The maximum of DNS servers */
+#ifndef DNS_MAX_SERVERS
+#define DNS_MAX_SERVERS 2
+#endif
+
+/** DNS do a name checking between the query and the response. */
+#ifndef DNS_DOES_NAME_CHECK
+#define DNS_DOES_NAME_CHECK 1
+#endif
+
+/** DNS use a local buffer if DNS_USES_STATIC_BUF=0, a static one if
+ DNS_USES_STATIC_BUF=1, or a dynamic one if DNS_USES_STATIC_BUF=2.
+ The buffer will be of size DNS_MSG_SIZE */
+#ifndef DNS_USES_STATIC_BUF
+#define DNS_USES_STATIC_BUF 1
+#endif
+
+/** DNS message max. size. Default value is RFC compliant. */
+#ifndef DNS_MSG_SIZE
+#define DNS_MSG_SIZE 512
+#endif
+
+/*
+ ---------------------------------
+ ---------- UDP options ----------
+ ---------------------------------
+*/
+/**
+ * LWIP_UDP==1: Turn on UDP.
+ */
+#ifndef LWIP_UDP
+#define LWIP_UDP 1
+#endif
+
+/**
+ * LWIP_UDPLITE==1: Turn on UDP-Lite. (Requires LWIP_UDP)
+ */
+#ifndef LWIP_UDPLITE
+#define LWIP_UDPLITE 0
+#endif
+
+/**
+ * UDP_TTL: Default Time-To-Live value.
+ */
+#ifndef UDP_TTL
+#define UDP_TTL (IP_DEFAULT_TTL)
+#endif
+
+/*
+ ---------------------------------
+ ---------- TCP options ----------
+ ---------------------------------
+*/
+/**
+ * LWIP_TCP==1: Turn on TCP.
+ */
+#ifndef LWIP_TCP
+#define LWIP_TCP 1
+#endif
+
+/**
+ * TCP_TTL: Default Time-To-Live value.
+ */
+#ifndef TCP_TTL
+#define TCP_TTL (IP_DEFAULT_TTL)
+#endif
+
+/**
+ * TCP_WND: The size of a TCP window.
+ */
+#ifndef TCP_WND
+#define TCP_WND 1024 //2048
+#endif
+
+/**
+ * TCP_MAXRTX: Maximum number of retransmissions of data segments.
+ */
+#ifndef TCP_MAXRTX
+#define TCP_MAXRTX 12
+#endif
+
+/**
+ * TCP_SYNMAXRTX: Maximum number of retransmissions of SYN segments.
+ */
+#ifndef TCP_SYNMAXRTX
+#define TCP_SYNMAXRTX 6
+#endif
+
+/**
+ * TCP_QUEUE_OOSEQ==1: TCP will queue segments that arrive out of order.
+ * Define to 0 if your device is low on memory.
+ */
+#ifndef TCP_QUEUE_OOSEQ
+#define TCP_QUEUE_OOSEQ 1
+#endif
+
+/**
+ * TCP_MSS: TCP Maximum segment size. (default is 128, a *very*
+ * conservative default.)
+ * For the receive side, this MSS is advertised to the remote side
+ * when opening a connection. For the transmit size, this MSS sets
+ * an upper limit on the MSS advertised by the remote host.
+ */
+#ifndef TCP_MSS
+#define TCP_MSS 128
+#endif
+
+/**
+ * TCP_CALCULATE_EFF_SEND_MSS: "The maximum size of a segment that TCP really
+ * sends, the 'effective send MSS,' MUST be the smaller of the send MSS (which
+ * reflects the available reassembly buffer size at the remote host) and the
+ * largest size permitted by the IP layer" (RFC 1122)
+ * Setting this to 1 enables code that checks TCP_MSS against the MTU of the
+ * netif used for a connection and limits the MSS if it would be too big otherwise.
+ */
+#ifndef TCP_CALCULATE_EFF_SEND_MSS
+#define TCP_CALCULATE_EFF_SEND_MSS 1
+#endif
+
+
+/**
+ * TCP_SND_BUF: TCP sender buffer space (bytes).
+ */
+#ifndef TCP_SND_BUF
+#define TCP_SND_BUF 256
+#endif
+
+/**
+ * TCP_SND_QUEUELEN: TCP sender buffer space (pbufs). This must be at least
+ * as much as (2 * TCP_SND_BUF/TCP_MSS) for things to work.
+ */
+#ifndef TCP_SND_QUEUELEN
+#define TCP_SND_QUEUELEN (4 * (TCP_SND_BUF/TCP_MSS))
+#endif
+
+/**
+ * TCP_SNDLOWAT: TCP writable space (bytes). This must be less than or equal
+ * to TCP_SND_BUF. It is the amount of space which must be available in the
+ * TCP snd_buf for select to return writable.
+ */
+#ifndef TCP_SNDLOWAT
+#define TCP_SNDLOWAT (TCP_SND_BUF/2)
+#endif
+
+/**
+ * TCP_LISTEN_BACKLOG: Enable the backlog option for tcp listen pcb.
+ */
+#ifndef TCP_LISTEN_BACKLOG
+#define TCP_LISTEN_BACKLOG 0
+#endif
+
+/**
+ * The maximum allowed backlog for TCP listen netconns.
+ * This backlog is used unless another is explicitly specified.
+ * 0xff is the maximum (u8_t).
+ */
+#ifndef TCP_DEFAULT_LISTEN_BACKLOG
+#define TCP_DEFAULT_LISTEN_BACKLOG 0xff
+#endif
+
+/**
+ * LWIP_EVENT_API and LWIP_CALLBACK_API: Only one of these should be set to 1.
+ * LWIP_EVENT_API==1: The user defines lwip_tcp_event() to receive all
+ * events (accept, sent, etc) that happen in the system.
+ * LWIP_CALLBACK_API==1: The PCB callback function is called directly
+ * for the event.
+ */
+#ifndef LWIP_EVENT_API
+#define LWIP_EVENT_API 0
+#define LWIP_CALLBACK_API 1
+#else
+#define LWIP_EVENT_API 1
+#define LWIP_CALLBACK_API 0
+#endif
+
+
+/*
+ ----------------------------------
+ ---------- Pbuf options ----------
+ ----------------------------------
+*/
+/**
+ * PBUF_LINK_HLEN: the number of bytes that should be allocated for a
+ * link level header. The default is 14, the standard value for
+ * Ethernet.
+ */
+#ifndef PBUF_LINK_HLEN
+#define PBUF_LINK_HLEN 14
+#endif
+
+/**
+ * PBUF_POOL_BUFSIZE: the size of each pbuf in the pbuf pool. The default is
+ * designed to accomodate single full size TCP frame in one pbuf, including
+ * TCP_MSS, IP header, and link header.
+ */
+#ifndef PBUF_POOL_BUFSIZE
+#define PBUF_POOL_BUFSIZE LWIP_MEM_ALIGN_SIZE(TCP_MSS+40+PBUF_LINK_HLEN)
+#endif
+
+/*
+ ------------------------------------------------
+ ---------- Network Interfaces options ----------
+ ------------------------------------------------
+*/
+/**
+ * LWIP_NETIF_HOSTNAME==1: use DHCP_OPTION_HOSTNAME with netif's hostname
+ * field.
+ */
+#ifndef LWIP_NETIF_HOSTNAME
+#define LWIP_NETIF_HOSTNAME 0
+#endif
+
+/**
+ * LWIP_NETIF_API==1: Support netif api (in netifapi.c)
+ */
+#ifndef LWIP_NETIF_API
+#define LWIP_NETIF_API 1
+#endif
+
+/**
+ * LWIP_NETIF_STATUS_CALLBACK==1: Support a callback function whenever an interface
+ * changes its up/down status (i.e., due to DHCP IP acquistion)
+ */
+#ifndef LWIP_NETIF_STATUS_CALLBACK
+#define LWIP_NETIF_STATUS_CALLBACK 0
+#endif
+
+/**
+ * LWIP_NETIF_LINK_CALLBACK==1: Support a callback function from an interface
+ * whenever the link changes (i.e., link down)
+ */
+#ifndef LWIP_NETIF_LINK_CALLBACK
+#define LWIP_NETIF_LINK_CALLBACK 0
+#endif
+
+/**
+ * LWIP_NETIF_HWADDRHINT==1: Cache link-layer-address hints (e.g. table
+ * indices) in struct netif. TCP and UDP can make use of this to prevent
+ * scanning the ARP table for every sent packet. While this is faster for big
+ * ARP tables or many concurrent connections, it might be counterproductive
+ * if you have a tiny ARP table or if there never are concurrent connections.
+ */
+#ifndef LWIP_NETIF_HWADDRHINT
+#define LWIP_NETIF_HWADDRHINT 0
+#endif
+
+/*
+ ------------------------------------
+ ---------- LOOPIF options ----------
+ ------------------------------------
+*/
+/**
+ * LWIP_HAVE_LOOPIF==1: Support loop interface (127.0.0.1) and loopif.c
+ */
+#ifndef LWIP_HAVE_LOOPIF
+#define LWIP_HAVE_LOOPIF 0
+#endif
+
+/**
+ * LWIP_LOOPIF_MULTITHREADING: Indicates whether threading is enabled in
+ * the system, as LOOPIF must change how it behaves depending on this setting.
+ * Setting this is needed to avoid reentering non-reentrant functions like
+ * tcp_input().
+ * LWIP_LOOPIF_MULTITHREADING==1: Indicates that the user is using a
+ * multithreaded environment like tcpip.c. In this case, netif->input()
+ * is called directly.
+ * LWIP_LOOPIF_MULTITHREADING==0: Indicates a polling (or NO_SYS) setup.
+ * The packets are put on a list and loopif_poll() must be called in
+ * the main application loop.
+ */
+#ifndef LWIP_LOOPIF_MULTITHREADING
+#define LWIP_LOOPIF_MULTITHREADING 1
+#endif
+
+/*
+ ------------------------------------
+ ---------- Thread options ----------
+ ------------------------------------
+*/
+/**
+ * TCPIP_THREAD_NAME: The name assigned to the main tcpip thread.
+ */
+#ifndef TCPIP_THREAD_NAME
+#define TCPIP_THREAD_NAME "tcpip_thread"
+#endif
+
+/**
+ * TCPIP_THREAD_STACKSIZE: The stack size used by the main tcpip thread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef TCPIP_THREAD_STACKSIZE
+#define TCPIP_THREAD_STACKSIZE 0
+#endif
+
+/**
+ * TCPIP_THREAD_PRIO: The priority assigned to the main tcpip thread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef TCPIP_THREAD_PRIO
+#define TCPIP_THREAD_PRIO 1
+#endif
+
+/**
+ * TCPIP_MBOX_SIZE: The mailbox size for the tcpip thread messages
+ * The queue size value itself is platform-dependent, but is passed to
+ * sys_mbox_new() when tcpip_init is called.
+ */
+#ifndef TCPIP_MBOX_SIZE
+#define TCPIP_MBOX_SIZE 0
+#endif
+
+/**
+ * SLIPIF_THREAD_NAME: The name assigned to the slipif_loop thread.
+ */
+#ifndef SLIPIF_THREAD_NAME
+#define SLIPIF_THREAD_NAME "slipif_loop"
+#endif
+
+/**
+ * SLIP_THREAD_STACKSIZE: The stack size used by the slipif_loop thread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef SLIPIF_THREAD_STACKSIZE
+#define SLIPIF_THREAD_STACKSIZE 0
+#endif
+
+/**
+ * SLIPIF_THREAD_PRIO: The priority assigned to the slipif_loop thread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef SLIPIF_THREAD_PRIO
+#define SLIPIF_THREAD_PRIO 1
+#endif
+
+/**
+ * PPP_THREAD_NAME: The name assigned to the pppMain thread.
+ */
+#ifndef PPP_THREAD_NAME
+#define PPP_THREAD_NAME "pppMain"
+#endif
+
+/**
+ * PPP_THREAD_STACKSIZE: The stack size used by the pppMain thread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef PPP_THREAD_STACKSIZE
+#define PPP_THREAD_STACKSIZE 0
+#endif
+
+/**
+ * PPP_THREAD_PRIO: The priority assigned to the pppMain thread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef PPP_THREAD_PRIO
+#define PPP_THREAD_PRIO 1
+#endif
+
+/**
+ * DEFAULT_THREAD_NAME: The name assigned to any other lwIP thread.
+ */
+#ifndef DEFAULT_THREAD_NAME
+#define DEFAULT_THREAD_NAME "lwIP"
+#endif
+
+/**
+ * DEFAULT_THREAD_STACKSIZE: The stack size used by any other lwIP thread.
+ * The stack size value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef DEFAULT_THREAD_STACKSIZE
+#define DEFAULT_THREAD_STACKSIZE 0
+#endif
+
+/**
+ * DEFAULT_THREAD_PRIO: The priority assigned to any other lwIP thread.
+ * The priority value itself is platform-dependent, but is passed to
+ * sys_thread_new() when the thread is created.
+ */
+#ifndef DEFAULT_THREAD_PRIO
+#define DEFAULT_THREAD_PRIO 1
+#endif
+
+/**
+ * DEFAULT_RAW_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
+ * NETCONN_RAW. The queue size value itself is platform-dependent, but is passed
+ * to sys_mbox_new() when the recvmbox is created.
+ */
+#ifndef DEFAULT_RAW_RECVMBOX_SIZE
+#define DEFAULT_RAW_RECVMBOX_SIZE 0
+#endif
+
+/**
+ * DEFAULT_UDP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
+ * NETCONN_UDP. The queue size value itself is platform-dependent, but is passed
+ * to sys_mbox_new() when the recvmbox is created.
+ */
+#ifndef DEFAULT_UDP_RECVMBOX_SIZE
+#define DEFAULT_UDP_RECVMBOX_SIZE 0
+#endif
+
+/**
+ * DEFAULT_TCP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
+ * NETCONN_TCP. The queue size value itself is platform-dependent, but is passed
+ * to sys_mbox_new() when the recvmbox is created.
+ */
+#ifndef DEFAULT_TCP_RECVMBOX_SIZE
+#define DEFAULT_TCP_RECVMBOX_SIZE 0
+#endif
+
+/**
+ * DEFAULT_ACCEPTMBOX_SIZE: The mailbox size for the incoming connections.
+ * The queue size value itself is platform-dependent, but is passed to
+ * sys_mbox_new() when the acceptmbox is created.
+ */
+#ifndef DEFAULT_ACCEPTMBOX_SIZE
+#define DEFAULT_ACCEPTMBOX_SIZE 0
+#endif
+
+/*
+ ----------------------------------------------
+ ---------- Sequential layer options ----------
+ ----------------------------------------------
+*/
+/**
+ * LWIP_TCPIP_CORE_LOCKING: (EXPERIMENTAL!)
+ * Don't use it if you're not an active lwIP project member
+ */
+#ifndef LWIP_TCPIP_CORE_LOCKING
+#define LWIP_TCPIP_CORE_LOCKING 0
+#endif
+
+/**
+ * LWIP_NETCONN==1: Enable Netconn API (require to use api_lib.c)
+ */
+#ifndef LWIP_NETCONN
+#define LWIP_NETCONN 1
+#endif
+
+/*
+ ------------------------------------
+ ---------- Socket options ----------
+ ------------------------------------
+*/
+/**
+ * LWIP_SOCKET==1: Enable Socket API (require to use sockets.c)
+ */
+#ifndef LWIP_SOCKET
+#define LWIP_SOCKET 1
+#endif
+
+/**
+ * LWIP_COMPAT_SOCKETS==1: Enable BSD-style sockets functions names.
+ * (only used if you use sockets.c)
+ */
+#ifndef LWIP_COMPAT_SOCKETS
+#define LWIP_COMPAT_SOCKETS 1
+#endif
+
+/**
+ * LWIP_POSIX_SOCKETS_IO_NAMES==1: Enable POSIX-style sockets functions names.
+ * Disable this option if you use a POSIX operating system that uses the same
+ * names (read, write & close). (only used if you use sockets.c)
+ */
+#ifndef LWIP_POSIX_SOCKETS_IO_NAMES
+#define LWIP_POSIX_SOCKETS_IO_NAMES 1
+#endif
+
+/**
+ * LWIP_TCP_KEEPALIVE==1: Enable TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT
+ * options processing. Note that TCP_KEEPIDLE and TCP_KEEPINTVL have to be set
+ * in seconds. (does not require sockets.c, and will affect tcp.c)
+ */
+#ifndef LWIP_TCP_KEEPALIVE
+#define LWIP_TCP_KEEPALIVE 0
+#endif
+
+/**
+ * LWIP_SO_RCVTIMEO==1: Enable SO_RCVTIMEO processing.
+ */
+#ifndef LWIP_SO_RCVTIMEO
+#define LWIP_SO_RCVTIMEO 0
+#endif
+
+/**
+ * LWIP_SO_RCVBUF==1: Enable SO_RCVBUF processing.
+ */
+#ifndef LWIP_SO_RCVBUF
+#define LWIP_SO_RCVBUF 0
+#endif
+
+/**
+ * SO_REUSE==1: Enable SO_REUSEADDR and SO_REUSEPORT options. DO NOT USE!
+ */
+#ifndef SO_REUSE
+#define SO_REUSE 0
+#endif
+
+/*
+ ----------------------------------------
+ ---------- Statistics options ----------
+ ----------------------------------------
+*/
+/**
+ * LWIP_STATS==1: Enable statistics collection in lwip_stats.
+ */
+#ifndef LWIP_STATS
+#define LWIP_STATS 1
+#endif
+
+#if LWIP_STATS
+
+/**
+ * LWIP_STATS_DISPLAY==1: Compile in the statistics output functions.
+ */
+#ifndef LWIP_STATS_DISPLAY
+#define LWIP_STATS_DISPLAY 0
+#endif
+
+/**
+ * LINK_STATS==1: Enable link stats.
+ */
+#ifndef LINK_STATS
+#define LINK_STATS 1
+#endif
+
+/**
+ * ETHARP_STATS==1: Enable etharp stats.
+ */
+#ifndef ETHARP_STATS
+#define ETHARP_STATS (LWIP_ARP)
+#endif
+
+/**
+ * IP_STATS==1: Enable IP stats.
+ */
+#ifndef IP_STATS
+#define IP_STATS 1
+#endif
+
+/**
+ * IPFRAG_STATS==1: Enable IP fragmentation stats. Default is
+ * on if using either frag or reass.
+ */
+#ifndef IPFRAG_STATS
+#define IPFRAG_STATS (IP_REASSEMBLY || IP_FRAG)
+#endif
+
+/**
+ * ICMP_STATS==1: Enable ICMP stats.
+ */
+#ifndef ICMP_STATS
+#define ICMP_STATS 1
+#endif
+
+/**
+ * IGMP_STATS==1: Enable IGMP stats.
+ */
+#ifndef IGMP_STATS
+#define IGMP_STATS (LWIP_IGMP)
+#endif
+
+/**
+ * UDP_STATS==1: Enable UDP stats. Default is on if
+ * UDP enabled, otherwise off.
+ */
+#ifndef UDP_STATS
+#define UDP_STATS (LWIP_UDP)
+#endif
+
+/**
+ * TCP_STATS==1: Enable TCP stats. Default is on if TCP
+ * enabled, otherwise off.
+ */
+#ifndef TCP_STATS
+#define TCP_STATS (LWIP_TCP)
+#endif
+
+/**
+ * MEM_STATS==1: Enable mem.c stats.
+ */
+#ifndef MEM_STATS
+#define MEM_STATS 1
+#endif
+
+/**
+ * MEMP_STATS==1: Enable memp.c pool stats.
+ */
+#ifndef MEMP_STATS
+#define MEMP_STATS 1
+#endif
+
+/**
+ * SYS_STATS==1: Enable system stats (sem and mbox counts, etc).
+ */
+#ifndef SYS_STATS
+#define SYS_STATS 1
+#endif
+
+#else
+
+#define LINK_STATS 0
+#define IP_STATS 0
+#define IPFRAG_STATS 0
+#define ICMP_STATS 0
+#define IGMP_STATS 0
+#define UDP_STATS 0
+#define TCP_STATS 0
+#define MEM_STATS 0
+#define MEMP_STATS 0
+#define SYS_STATS 0
+#define LWIP_STATS_DISPLAY 0
+
+#endif /* LWIP_STATS */
+
+/*
+ ---------------------------------
+ ---------- PPP options ----------
+ ---------------------------------
+*/
+/**
+ * PPP_SUPPORT==1: Enable PPP.
+ */
+#ifndef PPP_SUPPORT
+#define PPP_SUPPORT 0
+#endif
+
+/**
+ * PPPOE_SUPPORT==1: Enable PPP Over Ethernet
+ */
+#ifndef PPPOE_SUPPORT
+#define PPPOE_SUPPORT 0
+#endif
+
+/**
+ * PPPOS_SUPPORT==1: Enable PPP Over Serial
+ */
+#ifndef PPPOS_SUPPORT
+#define PPPOS_SUPPORT PPP_SUPPORT
+#endif
+
+#if PPP_SUPPORT
+
+/**
+ * NUM_PPP: Max PPP sessions.
+ */
+#ifndef NUM_PPP
+#define NUM_PPP 1
+#endif
+
+/**
+ * PAP_SUPPORT==1: Support PAP.
+ */
+#ifndef PAP_SUPPORT
+#define PAP_SUPPORT 0
+#endif
+
+/**
+ * CHAP_SUPPORT==1: Support CHAP.
+ */
+#ifndef CHAP_SUPPORT
+#define CHAP_SUPPORT 0
+#endif
+
+/**
+ * MSCHAP_SUPPORT==1: Support MSCHAP. CURRENTLY NOT SUPPORTED! DO NOT SET!
+ */
+#ifndef MSCHAP_SUPPORT
+#define MSCHAP_SUPPORT 0
+#endif
+
+/**
+ * CBCP_SUPPORT==1: Support CBCP. CURRENTLY NOT SUPPORTED! DO NOT SET!
+ */
+#ifndef CBCP_SUPPORT
+#define CBCP_SUPPORT 0
+#endif
+
+/**
+ * CCP_SUPPORT==1: Support CCP. CURRENTLY NOT SUPPORTED! DO NOT SET!
+ */
+#ifndef CCP_SUPPORT
+#define CCP_SUPPORT 0
+#endif
+
+/**
+ * VJ_SUPPORT==1: Support VJ header compression.
+ */
+#ifndef VJ_SUPPORT
+#define VJ_SUPPORT 0
+#endif
+
+/**
+ * MD5_SUPPORT==1: Support MD5 (see also CHAP).
+ */
+#ifndef MD5_SUPPORT
+#define MD5_SUPPORT 0
+#endif
+
+/*
+ * Timeouts
+ */
+#ifndef FSM_DEFTIMEOUT
+#define FSM_DEFTIMEOUT 6 /* Timeout time in seconds */
+#endif
+
+#ifndef FSM_DEFMAXTERMREQS
+#define FSM_DEFMAXTERMREQS 2 /* Maximum Terminate-Request transmissions */
+#endif
+
+#ifndef FSM_DEFMAXCONFREQS
+#define FSM_DEFMAXCONFREQS 10 /* Maximum Configure-Request transmissions */
+#endif
+
+#ifndef FSM_DEFMAXNAKLOOPS
+#define FSM_DEFMAXNAKLOOPS 5 /* Maximum number of nak loops */
+#endif
+
+#ifndef UPAP_DEFTIMEOUT
+#define UPAP_DEFTIMEOUT 6 /* Timeout (seconds) for retransmitting req */
+#endif
+
+#ifndef UPAP_DEFREQTIME
+#define UPAP_DEFREQTIME 30 /* Time to wait for auth-req from peer */
+#endif
+
+#ifndef CHAP_DEFTIMEOUT
+#define CHAP_DEFTIMEOUT 6 /* Timeout time in seconds */
+#endif
+
+#ifndef CHAP_DEFTRANSMITS
+#define CHAP_DEFTRANSMITS 10 /* max # times to send challenge */
+#endif
+
+/* Interval in seconds between keepalive echo requests, 0 to disable. */
+#ifndef LCP_ECHOINTERVAL
+#define LCP_ECHOINTERVAL 0
+#endif
+
+/* Number of unanswered echo requests before failure. */
+#ifndef LCP_MAXECHOFAILS
+#define LCP_MAXECHOFAILS 3
+#endif
+
+/* Max Xmit idle time (in jiffies) before resend flag char. */
+#ifndef PPP_MAXIDLEFLAG
+#define PPP_MAXIDLEFLAG 100
+#endif
+
+/*
+ * Packet sizes
+ *
+ * Note - lcp shouldn't be allowed to negotiate stuff outside these
+ * limits. See lcp.h in the pppd directory.
+ * (XXX - these constants should simply be shared by lcp.c instead
+ * of living in lcp.h)
+ */
+#define PPP_MTU 1500 /* Default MTU (size of Info field) */
+#ifndef PPP_MAXMTU
+/* #define PPP_MAXMTU 65535 - (PPP_HDRLEN + PPP_FCSLEN) */
+#define PPP_MAXMTU 1500 /* Largest MTU we allow */
+#endif
+#define PPP_MINMTU 64
+#define PPP_MRU 1500 /* default MRU = max length of info field */
+#define PPP_MAXMRU 1500 /* Largest MRU we allow */
+#ifndef PPP_DEFMRU
+#define PPP_DEFMRU 296 /* Try for this */
+#endif
+#define PPP_MINMRU 128 /* No MRUs below this */
+
+
+#define MAXNAMELEN 256 /* max length of hostname or name for auth */
+#define MAXSECRETLEN 256 /* max length of password or secret */
+
+#endif /* PPP_SUPPORT */
+
+/*
+ --------------------------------------
+ ---------- Checksum options ----------
+ --------------------------------------
+*/
+/**
+ * CHECKSUM_GEN_IP==1: Generate checksums in software for outgoing IP packets.
+ */
+#ifndef CHECKSUM_GEN_IP
+#define CHECKSUM_GEN_IP 1
+#endif
+
+/**
+ * CHECKSUM_GEN_UDP==1: Generate checksums in software for outgoing UDP packets.
+ */
+#ifndef CHECKSUM_GEN_UDP
+#define CHECKSUM_GEN_UDP 1
+#endif
+
+/**
+ * CHECKSUM_GEN_TCP==1: Generate checksums in software for outgoing TCP packets.
+ */
+#ifndef CHECKSUM_GEN_TCP
+#define CHECKSUM_GEN_TCP 1
+#endif
+
+/**
+ * CHECKSUM_CHECK_IP==1: Check checksums in software for incoming IP packets.
+ */
+#ifndef CHECKSUM_CHECK_IP
+#define CHECKSUM_CHECK_IP 1
+#endif
+
+/**
+ * CHECKSUM_CHECK_UDP==1: Check checksums in software for incoming UDP packets.
+ */
+#ifndef CHECKSUM_CHECK_UDP
+#define CHECKSUM_CHECK_UDP 1
+#endif
+
+/**
+ * CHECKSUM_CHECK_TCP==1: Check checksums in software for incoming TCP packets.
+ */
+#ifndef CHECKSUM_CHECK_TCP
+#define CHECKSUM_CHECK_TCP 1
+#endif
+
+/*
+ ---------------------------------------
+ ---------- Debugging options ----------
+ ---------------------------------------
+*/
+/**
+ * LWIP_DBG_MIN_LEVEL: After masking, the value of the debug is
+ * compared against this value. If it is smaller, then debugging
+ * messages are written.
+ */
+#ifndef LWIP_DBG_MIN_LEVEL
+#define LWIP_DBG_MIN_LEVEL LWIP_DBG_LEVEL_OFF
+#endif
+
+/**
+ * LWIP_DBG_TYPES_ON: A mask that can be used to globally enable/disable
+ * debug messages of certain types.
+ */
+#ifndef LWIP_DBG_TYPES_ON
+#define LWIP_DBG_TYPES_ON LWIP_DBG_ON
+#endif
+
+/**
+ * ETHARP_DEBUG: Enable debugging in etharp.c.
+ */
+#ifndef ETHARP_DEBUG
+#define ETHARP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * NETIF_DEBUG: Enable debugging in netif.c.
+ */
+#ifndef NETIF_DEBUG
+#define NETIF_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * PBUF_DEBUG: Enable debugging in pbuf.c.
+ */
+#ifndef PBUF_DEBUG
+#define PBUF_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * API_LIB_DEBUG: Enable debugging in api_lib.c.
+ */
+#ifndef API_LIB_DEBUG
+#define API_LIB_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * API_MSG_DEBUG: Enable debugging in api_msg.c.
+ */
+#ifndef API_MSG_DEBUG
+#define API_MSG_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * SOCKETS_DEBUG: Enable debugging in sockets.c.
+ */
+#ifndef SOCKETS_DEBUG
+#define SOCKETS_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * ICMP_DEBUG: Enable debugging in icmp.c.
+ */
+#ifndef ICMP_DEBUG
+#define ICMP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * IGMP_DEBUG: Enable debugging in igmp.c.
+ */
+#ifndef IGMP_DEBUG
+#define IGMP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * INET_DEBUG: Enable debugging in inet.c.
+ */
+#ifndef INET_DEBUG
+#define INET_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * IP_DEBUG: Enable debugging for IP.
+ */
+#ifndef IP_DEBUG
+#define IP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * IP_REASS_DEBUG: Enable debugging in ip_frag.c for both frag & reass.
+ */
+#ifndef IP_REASS_DEBUG
+#define IP_REASS_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * RAW_DEBUG: Enable debugging in raw.c.
+ */
+#ifndef RAW_DEBUG
+#define RAW_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * MEM_DEBUG: Enable debugging in mem.c.
+ */
+#ifndef MEM_DEBUG
+#define MEM_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * MEMP_DEBUG: Enable debugging in memp.c.
+ */
+#ifndef MEMP_DEBUG
+#define MEMP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * SYS_DEBUG: Enable debugging in sys.c.
+ */
+#ifndef SYS_DEBUG
+#define SYS_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_DEBUG: Enable debugging for TCP.
+ */
+#ifndef TCP_DEBUG
+#define TCP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_INPUT_DEBUG: Enable debugging in tcp_in.c for incoming debug.
+ */
+#ifndef TCP_INPUT_DEBUG
+#define TCP_INPUT_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_FR_DEBUG: Enable debugging in tcp_in.c for fast retransmit.
+ */
+#ifndef TCP_FR_DEBUG
+#define TCP_FR_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_RTO_DEBUG: Enable debugging in TCP for retransmit
+ * timeout.
+ */
+#ifndef TCP_RTO_DEBUG
+#define TCP_RTO_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_CWND_DEBUG: Enable debugging for TCP congestion window.
+ */
+#ifndef TCP_CWND_DEBUG
+#define TCP_CWND_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_WND_DEBUG: Enable debugging in tcp_in.c for window updating.
+ */
+#ifndef TCP_WND_DEBUG
+#define TCP_WND_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_OUTPUT_DEBUG: Enable debugging in tcp_out.c output functions.
+ */
+#ifndef TCP_OUTPUT_DEBUG
+#define TCP_OUTPUT_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_RST_DEBUG: Enable debugging for TCP with the RST message.
+ */
+#ifndef TCP_RST_DEBUG
+#define TCP_RST_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCP_QLEN_DEBUG: Enable debugging for TCP queue lengths.
+ */
+#ifndef TCP_QLEN_DEBUG
+#define TCP_QLEN_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * UDP_DEBUG: Enable debugging in UDP.
+ */
+#ifndef UDP_DEBUG
+#define UDP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * TCPIP_DEBUG: Enable debugging in tcpip.c.
+ */
+#ifndef TCPIP_DEBUG
+#define TCPIP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * PPP_DEBUG: Enable debugging for PPP.
+ */
+#ifndef PPP_DEBUG
+#define PPP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * SLIP_DEBUG: Enable debugging in slipif.c.
+ */
+#ifndef SLIP_DEBUG
+#define SLIP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * DHCP_DEBUG: Enable debugging in dhcp.c.
+ */
+#ifndef DHCP_DEBUG
+#define DHCP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * AUTOIP_DEBUG: Enable debugging in autoip.c.
+ */
+#ifndef AUTOIP_DEBUG
+#define AUTOIP_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * SNMP_MSG_DEBUG: Enable debugging for SNMP messages.
+ */
+#ifndef SNMP_MSG_DEBUG
+#define SNMP_MSG_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * SNMP_MIB_DEBUG: Enable debugging for SNMP MIBs.
+ */
+#ifndef SNMP_MIB_DEBUG
+#define SNMP_MIB_DEBUG LWIP_DBG_OFF
+#endif
+
+/**
+ * DNS_DEBUG: Enable debugging for DNS.
+ */
+#ifndef DNS_DEBUG
+#define DNS_DEBUG LWIP_DBG_OFF
+#endif
+
+#endif /* __LWIP_OPT_H__ */
