Merged WolfSSL patch.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@11143 35acf78f-673a-0410-8e92-d51de3d6d3f4

3 files changed, 2722 insertions, 0 deletions

diff --git a/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/ffconf.h b/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/ffconf.h
new file mode 100644
index 000000000..18af4c94e
--- /dev/null
+++ b/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/ffconf.h
@@ -0,0 +1,272 @@
+/* CHIBIOS FIX */
+#include "ch.h"
+
+/*---------------------------------------------------------------------------/
+/  FatFs - Configuration file
+/---------------------------------------------------------------------------*/
+
+#define FFCONF_DEF 87030	/* Revision ID */
+
+/*---------------------------------------------------------------------------/
+/ Function Configurations
+/---------------------------------------------------------------------------*/
+
+#define FF_FS_READONLY	0
+/* This option switches read-only configuration. (0:Read/Write or 1:Read-only)
+/  Read-only configuration removes writing API functions, f_write(), f_sync(),
+/  f_unlink(), f_mkdir(), f_chmod(), f_rename(), f_truncate(), f_getfree()
+/  and optional writing functions as well. */
+
+
+#define FF_FS_MINIMIZE	0
+/* This option defines minimization level to remove some basic API functions.
+/
+/   0: All basic functions are enabled.
+/   1: f_stat(), f_getfree(), f_unlink(), f_mkdir(), f_truncate() and f_rename()
+/      are removed.
+/   2: f_opendir(), f_readdir() and f_closedir() are removed in addition to 1.
+/   3: f_lseek() function is removed in addition to 2. */
+
+
+#define FF_USE_STRFUNC	0
+/* This option switches string functions, f_gets(), f_putc(), f_puts() and f_printf().
+/
+/  0: Disable string functions.
+/  1: Enable without LF-CRLF conversion.
+/  2: Enable with LF-CRLF conversion. */
+
+
+#define FF_USE_FIND		0
+/* This option switches filtered directory read functions, f_findfirst() and
+/  f_findnext(). (0:Disable, 1:Enable 2:Enable with matching altname[] too) */
+
+
+#define FF_USE_MKFS		0
+/* This option switches f_mkfs() function. (0:Disable or 1:Enable) */
+
+
+#define FF_USE_FASTSEEK	0
+/* This option switches fast seek function. (0:Disable or 1:Enable) */
+
+
+#define FF_USE_EXPAND	0
+/* This option switches f_expand function. (0:Disable or 1:Enable) */
+
+
+#define FF_USE_CHMOD	0
+/* This option switches attribute manipulation functions, f_chmod() and f_utime().
+/  (0:Disable or 1:Enable) Also FF_FS_READONLY needs to be 0 to enable this option. */
+
+
+#define FF_USE_LABEL	0
+/* This option switches volume label functions, f_getlabel() and f_setlabel().
+/  (0:Disable or 1:Enable) */
+
+
+#define FF_USE_FORWARD	0
+/* This option switches f_forward() function. (0:Disable or 1:Enable) */
+
+
+/*---------------------------------------------------------------------------/
+/ Locale and Namespace Configurations
+/---------------------------------------------------------------------------*/
+
+#define FF_CODE_PAGE      850
+/* This option specifies the OEM code page to be used on the target system.
+/  Incorrect code page setting can cause a file open failure.
+/
+/   437 - U.S.
+/   720 - Arabic
+/   737 - Greek
+/   771 - KBL
+/   775 - Baltic
+/   850 - Latin 1
+/   852 - Latin 2
+/   855 - Cyrillic
+/   857 - Turkish
+/   860 - Portuguese
+/   861 - Icelandic
+/   862 - Hebrew
+/   863 - Canadian French
+/   864 - Arabic
+/   865 - Nordic
+/   866 - Russian
+/   869 - Greek 2
+/   932 - Japanese (DBCS)
+/   936 - Simplified Chinese (DBCS)
+/   949 - Korean (DBCS)
+/   950 - Traditional Chinese (DBCS)
+/     0 - Include all code pages above and configured by f_setcp()
+*/
+
+
+#define    FF_USE_LFN    3
+#define    FF_MAX_LFN    255
+/* The FF_USE_LFN switches the support for LFN (long file name).
+/
+/   0: Disable LFN. FF_MAX_LFN has no effect.
+/   1: Enable LFN with static working buffer on the BSS. Always NOT thread-safe.
+/   2: Enable LFN with dynamic working buffer on the STACK.
+/   3: Enable LFN with dynamic working buffer on the HEAP.
+/
+/  To enable the LFN, Unicode handling functions (option/unicode.c) must be added
+/  to the project. The working buffer occupies (FF_MAX_LFN + 1) * 2 bytes and
+/  additional 608 bytes at exFAT enabled. FF_MAX_LFN can be in range from 12 to 255.
+/  It should be set 255 to support full featured LFN operations.
+/  When use stack for the working buffer, take care on stack overflow. When use heap
+/  memory for the working buffer, memory management functions, ff_memalloc() and
+/  ff_memfree(), must be added to the project. */
+
+
+#define FF_LFN_UNICODE	0
+/* This option switches character encoding on the API, 0:ANSI/OEM or 1:UTF-16,
+/  when LFN is enabled. Also behavior of string I/O functions will be affected by
+/  this option. When LFN is not enabled, this option has no effect.
+*/
+
+
+#define FF_STRF_ENCODE	3
+/* When FF_LFN_UNICODE = 1 with LFN enabled, string I/O functions, f_gets(),
+/  f_putc(), f_puts and f_printf() convert the character encoding in it.
+/  This option selects assumption of character encoding ON THE FILE to be
+/  read/written via those functions.
+/
+/   0: ANSI/OEM
+/   1: UTF-16LE
+/   2: UTF-16BE
+/   3: UTF-8
+*/
+
+
+#define FF_FS_RPATH		0
+/* This option configures support for relative path.
+/
+/   0: Disable relative path and remove related functions.
+/   1: Enable relative path. f_chdir() and f_chdrive() are available.
+/   2: f_getcwd() function is available in addition to 1.
+*/
+
+
+/*---------------------------------------------------------------------------/
+/ Drive/Volume Configurations
+/---------------------------------------------------------------------------*/
+
+#define FF_VOLUMES		1
+/* Number of volumes (logical drives) to be used. (1-10) */
+
+
+#define FF_STR_VOLUME_ID	0
+#define FF_VOLUME_STRS		"RAM","NAND","CF","SD","SD2","USB","USB2","USB3"
+/* FF_STR_VOLUME_ID switches string support for volume ID.
+/  When FF_STR_VOLUME_ID is set to 1, also pre-defined strings can be used as drive
+/  number in the path name. FF_VOLUME_STRS defines the drive ID strings for each
+/  logical drives. Number of items must be equal to FF_VOLUMES. Valid characters for
+/  the drive ID strings are: A-Z and 0-9. */
+
+
+#define FF_MULTI_PARTITION	0
+/* This option switches support for multiple volumes on the physical drive.
+/  By default (0), each logical drive number is bound to the same physical drive
+/  number and only an FAT volume found on the physical drive will be mounted.
+/  When this function is enabled (1), each logical drive number can be bound to
+/  arbitrary physical drive and partition listed in the VolToPart[]. Also f_fdisk()
+/  funciton will be available. */
+
+
+#define FF_MIN_SS		512
+#define FF_MAX_SS		512
+/* This set of options configures the range of sector size to be supported. (512,
+/  1024, 2048 or 4096) Always set both 512 for most systems, generic memory card and
+/  harddisk. But a larger value may be required for on-board flash memory and some
+/  type of optical media. When FF_MAX_SS is larger than FF_MIN_SS, FatFs is configured
+/  for variable sector size mode and disk_ioctl() function needs to implement
+/  GET_SECTOR_SIZE command. */
+
+
+#define FF_USE_TRIM		0
+/* This option switches support for ATA-TRIM. (0:Disable or 1:Enable)
+/  To enable Trim function, also CTRL_TRIM command should be implemented to the
+/  disk_ioctl() function. */
+
+
+#define FF_FS_NOFSINFO	0
+/* If you need to know correct free space on the FAT32 volume, set bit 0 of this
+/  option, and f_getfree() function at first time after volume mount will force
+/  a full FAT scan. Bit 1 controls the use of last allocated cluster number.
+/
+/  bit0=0: Use free cluster count in the FSINFO if available.
+/  bit0=1: Do not trust free cluster count in the FSINFO.
+/  bit1=0: Use last allocated cluster number in the FSINFO if available.
+/  bit1=1: Do not trust last allocated cluster number in the FSINFO.
+*/
+
+
+
+/*---------------------------------------------------------------------------/
+/ System Configurations
+/---------------------------------------------------------------------------*/
+
+#define FF_FS_TINY		0
+/* This option switches tiny buffer configuration. (0:Normal or 1:Tiny)
+/  At the tiny configuration, size of file object (FIL) is shrinked FF_MAX_SS bytes.
+/  Instead of private sector buffer eliminated from the file object, common sector
+/  buffer in the filesystem object (FATFS) is used for the file data transfer. */
+
+
+#define FF_FS_EXFAT       1
+/* This option switches support for exFAT filesystem. (0:Disable or 1:Enable)
+/  When enable exFAT, also LFN needs to be enabled.
+/  Note that enabling exFAT discards ANSI C (C89) compatibility. */
+
+
+#define FF_FS_NORTC       1
+#define FF_NORTC_MON	5
+#define FF_NORTC_MDAY	1
+#define FF_NORTC_YEAR	2017
+/* The option FF_FS_NORTC switches timestamp functiton. If the system does not have
+/  any RTC function or valid timestamp is not needed, set FF_FS_NORTC = 1 to disable
+/  the timestamp function. All objects modified by FatFs will have a fixed timestamp
+/  defined by FF_NORTC_MON, FF_NORTC_MDAY and FF_NORTC_YEAR in local time.
+/  To enable timestamp function (FF_FS_NORTC = 0), get_fattime() function need to be
+/  added to the project to read current time form real-time clock. FF_NORTC_MON,
+/  FF_NORTC_MDAY and FF_NORTC_YEAR have no effect.
+/  These options have no effect at read-only configuration (FF_FS_READONLY = 1). */
+
+
+#define FF_FS_LOCK		0
+/* The option FF_FS_LOCK switches file lock function to control duplicated file open
+/  and illegal operation to open objects. This option must be 0 when FF_FS_READONLY
+/  is 1.
+/
+/  0:  Disable file lock function. To avoid volume corruption, application program
+/      should avoid illegal open, remove and rename to the open objects.
+/  >0: Enable file lock function. The value defines how many files/sub-directories
+/      can be opened simultaneously under file lock control. Note that the file
+/      lock control is independent of re-entrancy. */
+
+
+#define FF_FS_REENTRANT   0
+#define FF_FS_TIMEOUT     MS2ST(1000)
+#define FF_SYNC_t         semaphore_t*
+/* The option FF_FS_REENTRANT switches the re-entrancy (thread safe) of the FatFs
+/  module itself. Note that regardless of this option, file access to different
+/  volume is always re-entrant and volume control functions, f_mount(), f_mkfs()
+/  and f_fdisk() function, are always not re-entrant. Only file/directory access
+/  to the same volume is under control of this function.
+/
+/   0: Disable re-entrancy. FF_FS_TIMEOUT and FF_SYNC_t have no effect.
+/   1: Enable re-entrancy. Also user provided synchronization handlers,
+/      ff_req_grant(), ff_rel_grant(), ff_del_syncobj() and ff_cre_syncobj()
+/      function, must be added to the project. Samples are available in
+/      option/syscall.c.
+/
+/  The FF_FS_TIMEOUT defines timeout period in unit of time tick.
+/  The FF_SYNC_t defines O/S dependent sync object type. e.g. HANDLE, ID, OS_EVENT*,
+/  SemaphoreHandle_t and etc. A header file for O/S definitions needs to be
+/  included somewhere in the scope of ff.h. */
+
+/* #include <windows.h>	// O/S definitions  */
+
+
+
+/*--- End of configuration options ---*/
diff --git a/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/httpd_opts.h b/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/httpd_opts.h
new file mode 100644
index 000000000..340db15f6
--- /dev/null
+++ b/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/httpd_opts.h
@@ -0,0 +1,323 @@
+/**
+ * @file
+ * HTTP server options list
+ */
+
+/*
+ * Copyright (c) 2001-2003 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>
+ *
+ * This version of the file has been modified by Texas Instruments to offer
+ * simple server-side-include (SSI) and Common Gateway Interface (CGI)
+ * capability.
+ */
+
+#ifndef LWIP_HDR_APPS_HTTPD_OPTS_H
+#define LWIP_HDR_APPS_HTTPD_OPTS_H
+
+#include "lwip/opt.h"
+
+/**
+ * @defgroup httpd_opts Options
+ * @ingroup httpd
+ * @{
+ */
+
+/** Set this to 1 to support CGI (old style) */
+#if !defined LWIP_HTTPD_CGI || defined __DOXYGEN__
+#define LWIP_HTTPD_CGI            0
+#endif
+
+/** Set this to 1 to support CGI (new style) */
+#if !defined LWIP_HTTPD_CGI_SSI || defined __DOXYGEN__
+#define LWIP_HTTPD_CGI_SSI        0
+#endif
+
+/** Set this to 1 to support SSI (Server-Side-Includes) */
+#if !defined LWIP_HTTPD_SSI || defined __DOXYGEN__
+#define LWIP_HTTPD_SSI            0
+#endif
+
+/** Set this to 1 to implement an SSI tag handler callback that gets a const char*
+ * to the tag (instead of an index into a pre-registered array of known tags) */
+#if !defined LWIP_HTTPD_SSI_RAW || defined __DOXYGEN__
+#define LWIP_HTTPD_SSI_RAW        0
+#endif
+
+/** Set this to 1 to support HTTP POST */
+#if !defined LWIP_HTTPD_SUPPORT_POST || defined __DOXYGEN__
+#define LWIP_HTTPD_SUPPORT_POST   0
+#endif
+
+/* The maximum number of parameters that the CGI handler can be sent. */
+#if !defined LWIP_HTTPD_MAX_CGI_PARAMETERS || defined __DOXYGEN__
+#define LWIP_HTTPD_MAX_CGI_PARAMETERS 16
+#endif
+
+/** LWIP_HTTPD_SSI_MULTIPART==1: SSI handler function is called with 2 more
+ * arguments indicating a counter for insert string that are too long to be
+ * inserted at once: the SSI handler function must then set 'next_tag_part'
+ * which will be passed back to it in the next call. */
+#if !defined LWIP_HTTPD_SSI_MULTIPART || defined __DOXYGEN__
+#define LWIP_HTTPD_SSI_MULTIPART    0
+#endif
+
+/* The maximum length of the string comprising the tag name */
+#if !defined LWIP_HTTPD_MAX_TAG_NAME_LEN || defined __DOXYGEN__
+#define LWIP_HTTPD_MAX_TAG_NAME_LEN 8
+#endif
+
+/* The maximum length of string that can be returned to replace any given tag */
+#if !defined LWIP_HTTPD_MAX_TAG_INSERT_LEN || defined __DOXYGEN__
+#define LWIP_HTTPD_MAX_TAG_INSERT_LEN 192
+#endif
+
+#if !defined LWIP_HTTPD_POST_MANUAL_WND || defined __DOXYGEN__
+#define LWIP_HTTPD_POST_MANUAL_WND  0
+#endif
+
+/** This string is passed in the HTTP header as "Server: " */
+#if !defined HTTPD_SERVER_AGENT || defined __DOXYGEN__
+#define HTTPD_SERVER_AGENT "lwIP/" LWIP_VERSION_STRING " (http://savannah.nongnu.org/projects/lwip)"
+#endif
+
+/** Set this to 1 if you want to include code that creates HTTP headers
+ * at runtime. Default is off: HTTP headers are then created statically
+ * by the makefsdata tool. Static headers mean smaller code size, but
+ * the (readonly) fsdata will grow a bit as every file includes the HTTP
+ * header. */
+#if !defined LWIP_HTTPD_DYNAMIC_HEADERS || defined __DOXYGEN__
+#define LWIP_HTTPD_DYNAMIC_HEADERS 0
+#endif
+
+#if !defined HTTPD_DEBUG || defined __DOXYGEN__
+#define HTTPD_DEBUG         LWIP_DBG_OFF
+#endif
+
+/** Set this to 1 to use a memp pool for allocating 
+ * struct http_state instead of the heap.
+ */
+#if !defined HTTPD_USE_MEM_POOL || defined __DOXYGEN__
+#define HTTPD_USE_MEM_POOL  0
+#endif
+
+/** The server port for HTTPD to use */
+#if !defined HTTPD_SERVER_PORT || defined __DOXYGEN__
+#define HTTPD_SERVER_PORT                   80
+#endif
+
+/** Maximum retries before the connection is aborted/closed.
+ * - number of times pcb->poll is called -> default is 4*500ms = 2s;
+ * - reset when pcb->sent is called
+ */
+#if !defined HTTPD_MAX_RETRIES || defined __DOXYGEN__
+#define HTTPD_MAX_RETRIES                   4
+#endif
+
+/** The poll delay is X*500ms */
+#if !defined HTTPD_POLL_INTERVAL || defined __DOXYGEN__
+#define HTTPD_POLL_INTERVAL                 4
+#endif
+
+/** Priority for tcp pcbs created by HTTPD (very low by default).
+ *  Lower priorities get killed first when running out of memory.
+ */
+#if !defined HTTPD_TCP_PRIO || defined __DOXYGEN__
+#define HTTPD_TCP_PRIO                      TCP_PRIO_MIN
+#endif
+
+/** Set this to 1 to enable timing each file sent */
+#if !defined LWIP_HTTPD_TIMING || defined __DOXYGEN__
+#define LWIP_HTTPD_TIMING                   0
+#endif
+/** Set this to 1 to enable timing each file sent */
+#if !defined HTTPD_DEBUG_TIMING || defined __DOXYGEN__
+#define HTTPD_DEBUG_TIMING                  LWIP_DBG_OFF
+#endif
+
+/** Set this to one to show error pages when parsing a request fails instead
+    of simply closing the connection. */
+#if !defined LWIP_HTTPD_SUPPORT_EXTSTATUS || defined __DOXYGEN__
+#define LWIP_HTTPD_SUPPORT_EXTSTATUS        0
+#endif
+
+/** Set this to 0 to drop support for HTTP/0.9 clients (to save some bytes) */
+#if !defined LWIP_HTTPD_SUPPORT_V09 || defined __DOXYGEN__
+#define LWIP_HTTPD_SUPPORT_V09              1
+#endif
+
+/** Set this to 1 to enable HTTP/1.1 persistent connections.
+ * ATTENTION: If the generated file system includes HTTP headers, these must
+ * include the "Connection: keep-alive" header (pass argument "-11" to makefsdata).
+ */
+#if !defined LWIP_HTTPD_SUPPORT_11_KEEPALIVE || defined __DOXYGEN__
+#define LWIP_HTTPD_SUPPORT_11_KEEPALIVE     0
+#endif
+
+/** Set this to 1 to support HTTP request coming in in multiple packets/pbufs */
+#if !defined LWIP_HTTPD_SUPPORT_REQUESTLIST || defined __DOXYGEN__
+#define LWIP_HTTPD_SUPPORT_REQUESTLIST      1
+#endif
+
+#if LWIP_HTTPD_SUPPORT_REQUESTLIST
+/** Number of rx pbufs to enqueue to parse an incoming request (up to the first
+    newline) */
+#if !defined LWIP_HTTPD_REQ_QUEUELEN || defined __DOXYGEN__
+#define LWIP_HTTPD_REQ_QUEUELEN             5
+#endif
+
+/** Number of (TCP payload-) bytes (in pbufs) to enqueue to parse and incoming
+    request (up to the first double-newline) */
+#if !defined LWIP_HTTPD_REQ_BUFSIZE || defined __DOXYGEN__
+#define LWIP_HTTPD_REQ_BUFSIZE              LWIP_HTTPD_MAX_REQ_LENGTH
+#endif
+
+/** Defines the maximum length of a HTTP request line (up to the first CRLF,
+    copied from pbuf into this a global buffer when pbuf- or packet-queues
+    are received - otherwise the input pbuf is used directly) */
+#if !defined LWIP_HTTPD_MAX_REQ_LENGTH || defined __DOXYGEN__
+#define LWIP_HTTPD_MAX_REQ_LENGTH           LWIP_MIN(1023, (LWIP_HTTPD_REQ_QUEUELEN * PBUF_POOL_BUFSIZE))
+#endif
+#endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */
+
+/** This is the size of a static buffer used when URIs end with '/'.
+ * In this buffer, the directory requested is concatenated with all the
+ * configured default file names.
+ * Set to 0 to disable checking default filenames on non-root directories.
+ */
+#if !defined LWIP_HTTPD_MAX_REQUEST_URI_LEN || defined __DOXYGEN__
+#define LWIP_HTTPD_MAX_REQUEST_URI_LEN      63
+#endif
+
+/** Maximum length of the filename to send as response to a POST request,
+ * filled in by the application when a POST is finished.
+ */
+#if !defined LWIP_HTTPD_POST_MAX_RESPONSE_URI_LEN || defined __DOXYGEN__
+#define LWIP_HTTPD_POST_MAX_RESPONSE_URI_LEN 63
+#endif
+
+/** Set this to 0 to not send the SSI tag (default is on, so the tag will
+ * be sent in the HTML page */
+#if !defined LWIP_HTTPD_SSI_INCLUDE_TAG || defined __DOXYGEN__
+#define LWIP_HTTPD_SSI_INCLUDE_TAG           1
+#endif
+
+/** Set this to 1 to call tcp_abort when tcp_close fails with memory error.
+ * This can be used to prevent consuming all memory in situations where the
+ * HTTP server has low priority compared to other communication. */
+#if !defined LWIP_HTTPD_ABORT_ON_CLOSE_MEM_ERROR || defined __DOXYGEN__
+#define LWIP_HTTPD_ABORT_ON_CLOSE_MEM_ERROR  0
+#endif
+
+/** Set this to 1 to kill the oldest connection when running out of
+ * memory for 'struct http_state' or 'struct http_ssi_state'.
+ * ATTENTION: This puts all connections on a linked list, so may be kind of slow.
+ */
+#if !defined LWIP_HTTPD_KILL_OLD_ON_CONNECTIONS_EXCEEDED || defined __DOXYGEN__
+#define LWIP_HTTPD_KILL_OLD_ON_CONNECTIONS_EXCEEDED 0
+#endif
+
+/** Set this to 1 to send URIs without extension without headers
+ * (who uses this at all??) */
+#if !defined LWIP_HTTPD_OMIT_HEADER_FOR_EXTENSIONLESS_URI || defined __DOXYGEN__
+#define LWIP_HTTPD_OMIT_HEADER_FOR_EXTENSIONLESS_URI 0
+#endif
+
+/** Default: Tags are sent from struct http_state and are therefore volatile */
+#if !defined HTTP_IS_TAG_VOLATILE || defined __DOXYGEN__
+#define HTTP_IS_TAG_VOLATILE(ptr) TCP_WRITE_FLAG_COPY
+#endif
+
+/* By default, the httpd is limited to send 2*pcb->mss to keep resource usage low
+   when http is not an important protocol in the device. */
+#if !defined HTTPD_LIMIT_SENDING_TO_2MSS || defined __DOXYGEN__
+#define HTTPD_LIMIT_SENDING_TO_2MSS 1
+#endif
+
+/* Define this to a function that returns the maximum amount of data to enqueue.
+   The function have this signature: u16_t fn(struct tcp_pcb* pcb); */
+#if !defined HTTPD_MAX_WRITE_LEN || defined __DOXYGEN__
+#if HTTPD_LIMIT_SENDING_TO_2MSS
+#define HTTPD_MAX_WRITE_LEN(pcb)    (2 * tcp_mss(pcb))
+#endif
+#endif
+
+/*------------------- FS OPTIONS -------------------*/
+
+/** Set this to 1 and provide the functions:
+ * - "int fs_open_custom(struct fs_file *file, const char *name)"
+ *    Called first for every opened file to allow opening files
+ *    that are not included in fsdata(_custom).c
+ * - "void fs_close_custom(struct fs_file *file)"
+ *    Called to free resources allocated by fs_open_custom().
+ */
+#if !defined LWIP_HTTPD_CUSTOM_FILES || defined __DOXYGEN__
+#define LWIP_HTTPD_CUSTOM_FILES       0
+#endif
+
+/** Set this to 1 to support fs_read() to dynamically read file data.
+ * Without this (default=off), only one-block files are supported,
+ * and the contents must be ready after fs_open().
+ */
+#if !defined LWIP_HTTPD_DYNAMIC_FILE_READ || defined __DOXYGEN__
+#define LWIP_HTTPD_DYNAMIC_FILE_READ  0
+#endif
+
+/** Set this to 1 to include an application state argument per file
+ * that is opened. This allows to keep a state per connection/file.
+ */
+#if !defined LWIP_HTTPD_FILE_STATE || defined __DOXYGEN__
+#define LWIP_HTTPD_FILE_STATE         0
+#endif
+
+/** HTTPD_PRECALCULATED_CHECKSUM==1: include precompiled checksums for
+ * predefined (MSS-sized) chunks of the files to prevent having to calculate
+ * the checksums at runtime. */
+#if !defined HTTPD_PRECALCULATED_CHECKSUM || defined __DOXYGEN__
+#define HTTPD_PRECALCULATED_CHECKSUM  0
+#endif
+
+/** LWIP_HTTPD_FS_ASYNC_READ==1: support asynchronous read operations
+ * (fs_read_async returns FS_READ_DELAYED and calls a callback when finished).
+ */
+#if !defined LWIP_HTTPD_FS_ASYNC_READ || defined __DOXYGEN__
+#define LWIP_HTTPD_FS_ASYNC_READ      0
+#endif
+
+/** Set this to 1 to include "fsdata_custom.c" instead of "fsdata.c" for the
+ * file system (to prevent changing the file included in CVS) */
+#if !defined HTTPD_USE_CUSTOM_FSDATA || defined __DOXYGEN__
+#define HTTPD_USE_CUSTOM_FSDATA 0
+#endif
+
+/**
+ * @}
+ */
+
+#endif /* LWIP_HDR_APPS_HTTPD_OPTS_H */
diff --git a/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/lwipopts.h b/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/lwipopts.h
new file mode 100644
index 000000000..cebde0fc4
--- /dev/null
+++ b/demos/STM32/RT-STM32-LWIP-FATFS-USB-HTTPS/cfg/lwipopts.h
@@ -0,0 +1,2127 @@
+/**
+ * @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 __LWIPOPT_H__
+#define __LWIPOPT_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
+
+/**
+ * NO_SYS_NO_TIMERS==1: Drop support for sys_timeout when NO_SYS==1
+ * Mainly for compatibility to old versions.
+ */
+#ifndef NO_SYS_NO_TIMERS
+#define NO_SYS_NO_TIMERS                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
+
+/**
+* MEMP_MEM_MALLOC==1: Use mem_malloc/mem_free instead of the lwip pool allocator.
+* Especially useful with MEM_LIBC_MALLOC but handle with care regarding execution
+* speed and usage from interrupts!
+*/
+#ifndef MEMP_MEM_MALLOC
+#define MEMP_MEM_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                   4
+#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_SEPARATE_POOLS: if defined to 1, each pool is placed in its own array.
+ * This can be used to individually change the location of each pool.
+ * Default is one big array for all pools
+ */
+#ifndef MEMP_SEPARATE_POOLS
+#define MEMP_SEPARATE_POOLS             0
+#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 length needed is returned.
+ * To use this, MEMP_USE_CUSTOM_POOLS also has to be enabled.
+ */
+#ifndef MEM_USE_POOLS
+#define MEM_USE_POOLS                   0
+#endif
+
+/**
+ * MEM_USE_POOLS_TRY_BIGGER_POOL==1: if one malloc-pool is empty, try the next
+ * bigger pool - WARNING: THIS MIGHT WASTE MEMORY but it can make a system more
+ * reliable. */
+#ifndef MEM_USE_POOLS_TRY_BIGGER_POOL
+#define MEM_USE_POOLS_TRY_BIGGER_POOL   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
+
+/**
+ * Set this to 1 if you want to free PBUF_RAM pbufs (or call mem_free()) from
+ * interrupt context (or another context that doesn't allow waiting for a
+ * semaphore).
+ * If set to 1, mem_malloc will be protected by a semaphore and SYS_ARCH_PROTECT,
+ * while mem_free will only use SYS_ARCH_PROTECT. mem_malloc SYS_ARCH_UNPROTECTs
+ * with each loop so that mem_free can run.
+ *
+ * ATTENTION: As you can see from the above description, this leads to dis-/
+ * enabling interrupts often, which can be slow! Also, on low memory, mem_malloc
+ * can need longer.
+ *
+ * If you don't want that, at least for NO_SYS=0, you can still use the following
+ * functions to enqueue a deallocation call which then runs in the tcpip_thread
+ * context:
+ * - pbuf_free_callback(p);
+ * - mem_free_callback(m);
+ */
+#ifndef LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
+#define LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT 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 IP packets simultaneously queued for
+ * reassembly (whole packets, not fragments!)
+ */
+#ifndef MEMP_NUM_REASSDATA
+#define MEMP_NUM_REASSDATA              5
+#endif
+
+/**
+ * MEMP_NUM_FRAG_PBUF: the number of IP fragments simultaneously sent
+ * (fragments, not whole packets!).
+ * This is only used with IP_FRAG_USES_STATIC_BUF==0 and
+ * LWIP_NETIF_TX_SINGLE_PBUF==0 and only has to be > 1 with DMA-enabled MACs
+ * where the packet is not yet sent when netif->output returns.
+ */
+#ifndef MEMP_NUM_FRAG_PBUF
+#define MEMP_NUM_FRAG_PBUF              15
+#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)
+ * The default number of timeouts is calculated here for all enabled modules.
+ * The formula expects settings to be either '0' or '1'.
+ */
+#ifndef MEMP_NUM_SYS_TIMEOUT
+#define MEMP_NUM_SYS_TIMEOUT            (LWIP_TCP + IP_REASSEMBLY + LWIP_ARP + (2*LWIP_DHCP) + LWIP_AUTOIP + LWIP_IGMP + LWIP_DNS + PPP_SUPPORT)
+#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
+
+/**
+ * MEMP_NUM_SNMP_NODE: the number of leafs in the SNMP tree.
+ */
+#ifndef MEMP_NUM_SNMP_NODE
+#define MEMP_NUM_SNMP_NODE              50
+#endif
+
+/**
+ * MEMP_NUM_SNMP_ROOTNODE: the number of branches in the SNMP tree.
+ * Every branch has one leaf (MEMP_NUM_SNMP_NODE) at least!
+ */
+#ifndef MEMP_NUM_SNMP_ROOTNODE
+#define MEMP_NUM_SNMP_ROOTNODE          30
+#endif
+
+/**
+ * MEMP_NUM_SNMP_VARBIND: the number of concurrent requests (does not have to
+ * be changed normally) - 2 of these are used per request (1 for input,
+ * 1 for output)
+ */
+#ifndef MEMP_NUM_SNMP_VARBIND
+#define MEMP_NUM_SNMP_VARBIND           2
+#endif
+
+/**
+ * MEMP_NUM_SNMP_VALUE: the number of OID or values concurrently used
+ * (does not have to be changed normally) - 3 of these are used per request
+ * (1 for the value read and 2 for OIDs - input and output)
+ */
+#ifndef MEMP_NUM_SNMP_VALUE
+#define MEMP_NUM_SNMP_VALUE             3
+#endif
+
+/**
+ * MEMP_NUM_NETDB: the number of concurrently running lwip_addrinfo() calls
+ * (before freeing the corresponding memory using lwip_freeaddrinfo()).
+ */
+#ifndef MEMP_NUM_NETDB
+#define MEMP_NUM_NETDB                  1
+#endif
+
+/**
+ * MEMP_NUM_LOCALHOSTLIST: the number of host entries in the local host list
+ * if DNS_LOCAL_HOSTLIST_IS_DYNAMIC==1.
+ */
+#ifndef MEMP_NUM_LOCALHOSTLIST
+#define MEMP_NUM_LOCALHOSTLIST          1
+#endif
+
+/**
+ * MEMP_NUM_PPPOE_INTERFACES: the number of concurrently active PPPoE
+ * interfaces (only used with PPPOE_SUPPORT==1)
+ */
+#ifndef MEMP_NUM_PPPOE_INTERFACES
+#define MEMP_NUM_PPPOE_INTERFACES       1
+#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: Multiple outgoing packets are queued during hardware address
+ * resolution. By default, only the most recent packet is queued per IP address.
+ * This is sufficient for most protocols and mainly reduces TCP connection
+ * startup time. Set this to 1 if you know your application sends more than one
+ * packet in a row to an IP address that is not in the ARP cache.
+ */
+#ifndef ARP_QUEUEING
+#define ARP_QUEUEING                    0
+#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.
+ * The peer *is* in the ARP table if it requested our address before.
+ * Also notice that this slows down input processing of every IP packet!
+ */
+#ifndef ETHARP_TRUST_IP_MAC
+#define ETHARP_TRUST_IP_MAC             0
+#endif
+
+/**
+ * ETHARP_SUPPORT_VLAN==1: support receiving ethernet packets with VLAN header.
+ * Additionally, you can define ETHARP_VLAN_CHECK to an u16_t VLAN ID to check.
+ * If ETHARP_VLAN_CHECK is defined, only VLAN-traffic for this VLAN is accepted.
+ * If ETHARP_VLAN_CHECK is not defined, all traffic is accepted.
+ * Alternatively, define a function/define ETHARP_VLAN_CHECK_FN(eth_hdr, vlan)
+ * that returns 1 to accept a packet or 0 to drop a packet.
+ */
+#ifndef ETHARP_SUPPORT_VLAN
+#define ETHARP_SUPPORT_VLAN             0
+#endif
+
+/** LWIP_ETHERNET==1: enable ethernet support for PPPoE even though ARP
+ * might be disabled
+ */
+#ifndef LWIP_ETHERNET
+#define LWIP_ETHERNET                   (LWIP_ARP || PPPOE_SUPPORT)
+#endif
+
+/** ETH_PAD_SIZE: number of bytes added before the ethernet header to ensure
+ * alignment of payload after that header. Since the header is 14 bytes long,
+ * without this padding e.g. addresses in the IP header will not be aligned
+ * on a 32-bit boundary, so setting this to 2 can speed up 32-bit-platforms.
+ */
+#ifndef ETH_PAD_SIZE
+#define ETH_PAD_SIZE                    0
+#endif
+
+/** ETHARP_SUPPORT_STATIC_ENTRIES==1: enable code to support static ARP table
+ * entries (using etharp_add_static_entry/etharp_remove_static_entry).
+ */
+#ifndef ETHARP_SUPPORT_STATIC_ENTRIES
+#define ETHARP_SUPPORT_STATIC_ENTRIES   0
+#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 (or with LWIP_NETIF_TX_SINGLE_PBUF==1,
+ * new PBUF_RAM pbufs are used for fragments).
+ * ATTENTION: IP_FRAG_USES_STATIC_BUF==1 may not be used for DMA-enabled MACs!
+ */
+#ifndef IP_FRAG_USES_STATIC_BUF
+#define IP_FRAG_USES_STATIC_BUF         0
+#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
+
+/**
+ * IP_SOF_BROADCAST=1: Use the SOF_BROADCAST field to enable broadcast
+ * filter per pcb on udp and raw send operations. To enable broadcast filter
+ * on recv operations, you also have to set IP_SOF_BROADCAST_RECV=1.
+ */
+#ifndef IP_SOF_BROADCAST
+#define IP_SOF_BROADCAST                0
+#endif
+
+/**
+ * IP_SOF_BROADCAST_RECV (requires IP_SOF_BROADCAST=1) enable the broadcast
+ * filter on recv operations.
+ */
+#ifndef IP_SOF_BROADCAST_RECV
+#define IP_SOF_BROADCAST_RECV           0
+#endif
+
+/**
+ * IP_FORWARD_ALLOW_TX_ON_RX_NETIF==1: allow ip_forward() to send packets back
+ * out on the netif where it was received. This should only be used for
+ * wireless networks.
+ * ATTENTION: When this is 1, make sure your netif driver correctly marks incoming
+ * link-layer-broadcast/multicast packets as such using the corresponding pbuf flags!
+ */
+#ifndef IP_FORWARD_ALLOW_TX_ON_RX_NETIF
+#define IP_FORWARD_ALLOW_TX_ON_RX_NETIF 0
+#endif
+
+/**
+ * LWIP_RANDOMIZE_INITIAL_LOCAL_PORTS==1: randomize the local port for the first
+ * local TCP/UDP pcb (default==0). This can prevent creating predictable port
+ * numbers after booting a device.
+ */
+#ifndef LWIP_RANDOMIZE_INITIAL_LOCAL_PORTS
+#define LWIP_RANDOMIZE_INITIAL_LOCAL_PORTS 0
+#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
+
+/**
+ * LWIP_BROADCAST_PING==1: respond to broadcast pings (default is unicast only)
+ */
+#ifndef LWIP_BROADCAST_PING
+#define LWIP_BROADCAST_PING             0
+#endif
+
+/**
+ * LWIP_MULTICAST_PING==1: respond to multicast pings (default is unicast only)
+ */
+#ifndef LWIP_MULTICAST_PING
+#define LWIP_MULTICAST_PING             0
+#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
+
+/**
+ * LWIP_DHCP_AUTOIP_COOP_TRIES: Set to the number of DHCP DISCOVER probes
+ * that should be sent before falling back on AUTOIP. This can be set
+ * as low as 1 to get an AutoIP address very quickly, but you should
+ * be prepared to handle a changing IP address when DHCP overrides
+ * AutoIP.
+ */
+#ifndef LWIP_DHCP_AUTOIP_COOP_TRIES
+#define LWIP_DHCP_AUTOIP_COOP_TRIES     9
+#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.
+ * Does not have to be changed unless external MIBs answer request asynchronously
+ */
+#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: 
+ * When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your 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
+
+/**
+ * The maximum length of strings used. This affects the size of
+ * MEMP_SNMP_VALUE elements.
+ */
+#ifndef SNMP_MAX_OCTET_STRING_LEN
+#define SNMP_MAX_OCTET_STRING_LEN       127
+#endif
+
+/**
+ * The maximum depth of the SNMP tree.
+ * With private MIBs enabled, this depends on your MIB!
+ * This affects the size of MEMP_SNMP_VALUE elements.
+ */
+#ifndef SNMP_MAX_TREE_DEPTH
+#define SNMP_MAX_TREE_DEPTH             15
+#endif
+
+/**
+ * The size of the MEMP_SNMP_VALUE elements, normally calculated from
+ * SNMP_MAX_OCTET_STRING_LEN and SNMP_MAX_TREE_DEPTH.
+ */
+#ifndef SNMP_MAX_VALUE_SIZE
+#define SNMP_MAX_VALUE_SIZE             LWIP_MAX((SNMP_MAX_OCTET_STRING_LEN)+1, sizeof(s32_t)*(SNMP_MAX_TREE_DEPTH))
+#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 message max. size. Default value is RFC compliant. */
+#ifndef DNS_MSG_SIZE
+#define DNS_MSG_SIZE                    512
+#endif
+
+/** DNS_LOCAL_HOSTLIST: Implements a local host-to-address list. If enabled,
+ *  you have to define
+ *    #define DNS_LOCAL_HOSTLIST_INIT {{"host1", 0x123}, {"host2", 0x234}}
+ *  (an array of structs name/address, where address is an u32_t in network
+ *  byte order).
+ *
+ *  Instead, you can also use an external function:
+ *  #define DNS_LOOKUP_LOCAL_EXTERN(x) extern u32_t my_lookup_function(const char *name)
+ *  that returns the IP address or INADDR_NONE if not found.
+ */
+#ifndef DNS_LOCAL_HOSTLIST
+#define DNS_LOCAL_HOSTLIST              0
+#endif /* DNS_LOCAL_HOSTLIST */
+
+/** If this is turned on, the local host-list can be dynamically changed
+ *  at runtime. */
+#ifndef DNS_LOCAL_HOSTLIST_IS_DYNAMIC
+#define DNS_LOCAL_HOSTLIST_IS_DYNAMIC   0
+#endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
+
+/*
+   ---------------------------------
+   ---------- 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
+
+/**
+ * LWIP_NETBUF_RECVINFO==1: append destination addr and port to every netbuf.
+ */
+#ifndef LWIP_NETBUF_RECVINFO
+#define LWIP_NETBUF_RECVINFO            0
+#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.  This must be at least 
+ * (2 * TCP_MSS) for things to work well
+ */
+#ifndef TCP_WND
+#define TCP_WND                         (4 * TCP_MSS)
+#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                 (LWIP_TCP)
+#endif
+
+/**
+ * TCP_MSS: TCP Maximum segment size. (default is 536, a conservative default,
+ * you might want to increase this.)
+ * 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                         1480
+#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).
+ * To achieve good performance, this should be at least 2 * TCP_MSS.
+ */
+#ifndef TCP_SND_BUF
+#define TCP_SND_BUF                     (2 * TCP_MSS)
+#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 - 1))/(TCP_MSS))
+#endif
+
+/**
+ * TCP_SNDLOWAT: TCP writable space (bytes). This must be less than
+ * TCP_SND_BUF. It is the amount of space which must be available in the
+ * TCP snd_buf for select to return writable (combined with TCP_SNDQUEUELOWAT).
+ */
+#ifndef TCP_SNDLOWAT
+#define TCP_SNDLOWAT                    LWIP_MIN(LWIP_MAX(((TCP_SND_BUF)/2), (2 * TCP_MSS) + 1), (TCP_SND_BUF) - 1)
+#endif
+
+/**
+ * TCP_SNDQUEUELOWAT: TCP writable bufs (pbuf count). This must be less
+ * than TCP_SND_QUEUELEN. If the number of pbufs queued on a pcb drops below
+ * this number, select returns writable (combined with TCP_SNDLOWAT).
+ */
+#ifndef TCP_SNDQUEUELOWAT
+#define TCP_SNDQUEUELOWAT               LWIP_MAX(((TCP_SND_QUEUELEN)/2), 5)
+#endif
+
+/**
+ * TCP_OOSEQ_MAX_BYTES: The maximum number of bytes queued on ooseq per pcb.
+ * Default is 0 (no limit). Only valid for TCP_QUEUE_OOSEQ==0.
+ */
+#ifndef TCP_OOSEQ_MAX_BYTES
+#define TCP_OOSEQ_MAX_BYTES             0
+#endif
+
+/**
+ * TCP_OOSEQ_MAX_PBUFS: The maximum number of pbufs queued on ooseq per pcb.
+ * Default is 0 (no limit). Only valid for TCP_QUEUE_OOSEQ==0.
+ */
+#ifndef TCP_OOSEQ_MAX_PBUFS
+#define TCP_OOSEQ_MAX_PBUFS             0
+#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
+
+/**
+ * TCP_OVERSIZE: The maximum number of bytes that tcp_write may
+ * allocate ahead of time in an attempt to create shorter pbuf chains
+ * for transmission. The meaningful range is 0 to TCP_MSS. Some
+ * suggested values are:
+ *
+ * 0:         Disable oversized allocation. Each tcp_write() allocates a new
+              pbuf (old behaviour).
+ * 1:         Allocate size-aligned pbufs with minimal excess. Use this if your
+ *            scatter-gather DMA requires aligned fragments.
+ * 128:       Limit the pbuf/memory overhead to 20%.
+ * TCP_MSS:   Try to create unfragmented TCP packets.
+ * TCP_MSS/4: Try to create 4 fragments or less per TCP packet.
+ */
+#ifndef TCP_OVERSIZE
+#define TCP_OVERSIZE                    TCP_MSS
+#endif
+
+/**
+ * LWIP_TCP_TIMESTAMPS==1: support the TCP timestamp option.
+ */
+#ifndef LWIP_TCP_TIMESTAMPS
+#define LWIP_TCP_TIMESTAMPS             0
+#endif
+
+/**
+ * TCP_WND_UPDATE_THRESHOLD: difference in window to trigger an
+ * explicit window update
+ */
+#ifndef TCP_WND_UPDATE_THRESHOLD
+#define TCP_WND_UPDATE_THRESHOLD   (TCP_WND / 4)
+#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. This is the default.
+ */
+#if !defined(LWIP_EVENT_API) && !defined(LWIP_CALLBACK_API)
+#define LWIP_EVENT_API                  0
+#define LWIP_CALLBACK_API               1
+#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 + ETH_PAD_SIZE)
+#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                  0
+#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_REMOVE_CALLBACK==1: Support a callback function that is called
+ * when a netif has been removed
+ */
+#ifndef LWIP_NETIF_REMOVE_CALLBACK
+#define LWIP_NETIF_REMOVE_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
+
+/**
+ * LWIP_NETIF_LOOPBACK==1: Support sending packets with a destination IP
+ * address equal to the netif IP address, looping them back up the stack.
+ */
+#ifndef LWIP_NETIF_LOOPBACK
+#define LWIP_NETIF_LOOPBACK             0
+#endif
+
+/**
+ * LWIP_LOOPBACK_MAX_PBUFS: Maximum number of pbufs on queue for loopback
+ * sending for each netif (0 = disabled)
+ */
+#ifndef LWIP_LOOPBACK_MAX_PBUFS
+#define LWIP_LOOPBACK_MAX_PBUFS         0
+#endif
+
+/**
+ * LWIP_NETIF_LOOPBACK_MULTITHREADING: Indicates whether threading is enabled in
+ * the system, as netifs must change how they behave depending on this setting
+ * for the LWIP_NETIF_LOOPBACK option to work.
+ * Setting this is needed to avoid reentering non-reentrant functions like
+ * tcp_input().
+ *    LWIP_NETIF_LOOPBACK_MULTITHREADING==1: Indicates that the user is using a
+ *       multithreaded environment like tcpip.c. In this case, netif->input()
+ *       is called directly.
+ *    LWIP_NETIF_LOOPBACK_MULTITHREADING==0: Indicates a polling (or NO_SYS) setup.
+ *       The packets are put on a list and netif_poll() must be called in
+ *       the main application loop.
+ */
+#ifndef LWIP_NETIF_LOOPBACK_MULTITHREADING
+#define LWIP_NETIF_LOOPBACK_MULTITHREADING    (!NO_SYS)
+#endif
+
+/**
+ * LWIP_NETIF_TX_SINGLE_PBUF: if this is set to 1, lwIP tries to put all data
+ * to be sent into one single pbuf. This is for compatibility with DMA-enabled
+ * MACs that do not support scatter-gather.
+ * Beware that this might involve CPU-memcpy before transmitting that would not
+ * be needed without this flag! Use this only if you need to!
+ *
+ * @todo: TCP and IP-frag do not work with this, yet:
+ */
+#ifndef LWIP_NETIF_TX_SINGLE_PBUF
+#define LWIP_NETIF_TX_SINGLE_PBUF             0
+#endif /* LWIP_NETIF_TX_SINGLE_PBUF */
+
+/*
+   ------------------------------------
+   ---------- 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
+
+/*
+   ------------------------------------
+   ---------- SLIPIF options ----------
+   ------------------------------------
+*/
+/**
+ * LWIP_HAVE_SLIPIF==1: Support slip interface and slipif.c
+ */
+#ifndef LWIP_HAVE_SLIPIF
+#define LWIP_HAVE_SLIPIF                0
+#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          1024
+#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               (LOWPRIO + 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                 MEMP_NUM_PBUF
+#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         1024
+#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              (LOWPRIO + 1)
+#endif
+
+/**
+ * PPP_THREAD_NAME: The name assigned to the pppInputThread.
+ */
+#ifndef PPP_THREAD_NAME
+#define PPP_THREAD_NAME                "pppInputThread"
+#endif
+
+/**
+ * PPP_THREAD_STACKSIZE: The stack size used by the pppInputThread.
+ * 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            1024
+#endif
+
+/**
+ * PPP_THREAD_PRIO: The priority assigned to the pppInputThread.
+ * 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                 (LOWPRIO + 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        1024
+#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             (LOWPRIO + 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       4
+#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       4
+#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       40
+#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         4
+#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_TCPIP_CORE_LOCKING_INPUT: (EXPERIMENTAL!)
+ * Don't use it if you're not an active lwIP project member
+ */
+#ifndef LWIP_TCPIP_CORE_LOCKING_INPUT
+#define LWIP_TCPIP_CORE_LOCKING_INPUT   0
+#endif
+
+/**
+ * LWIP_NETCONN==1: Enable Netconn API (require to use api_lib.c)
+ */
+#ifndef LWIP_NETCONN
+#define LWIP_NETCONN                    1
+#endif
+
+/** LWIP_TCPIP_TIMEOUT==1: Enable tcpip_timeout/tcpip_untimeout tod create
+ * timers running in tcpip_thread from another thread.
+ */
+#ifndef LWIP_TCPIP_TIMEOUT
+#define LWIP_TCPIP_TIMEOUT              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_SNDTIMEO==1: Enable send timeout for sockets/netconns and
+ * SO_SNDTIMEO processing.
+ */
+#ifndef LWIP_SO_SNDTIMEO
+#define LWIP_SO_SNDTIMEO                0
+#endif
+
+/**
+ * LWIP_SO_RCVTIMEO==1: Enable receive timeout for sockets/netconns and
+ * 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
+
+/**
+ * If LWIP_SO_RCVBUF is used, this is the default value for recv_bufsize.
+ */
+#ifndef RECV_BUFSIZE_DEFAULT
+#define RECV_BUFSIZE_DEFAULT            INT_MAX
+#endif
+
+/**
+ * SO_REUSE==1: Enable SO_REUSEADDR option.
+ */
+#ifndef SO_REUSE
+#define SO_REUSE                        0
+#endif
+
+/**
+ * SO_REUSE_RXTOALL==1: Pass a copy of incoming broadcast/multicast packets
+ * to all local matches if SO_REUSEADDR is turned on.
+ * WARNING: Adds a memcpy for every packet if passing to more than one pcb!
+ */
+#ifndef SO_REUSE_RXTOALL
+#define SO_REUSE_RXTOALL                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                       ((MEM_LIBC_MALLOC == 0) && (MEM_USE_POOLS == 0))
+#endif
+
+/**
+ * MEMP_STATS==1: Enable memp.c pool stats.
+ */
+#ifndef MEMP_STATS
+#define MEMP_STATS                      (MEMP_MEM_MALLOC == 0)
+#endif
+
+/**
+ * SYS_STATS==1: Enable system stats (sem and mbox counts, etc).
+ */
+#ifndef SYS_STATS
+#define SYS_STATS                       (NO_SYS == 0)
+#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 */
+
+#ifndef MAXNAMELEN
+#define MAXNAMELEN                      256     /* max length of hostname or name for auth */
+#endif
+#ifndef MAXSECRETLEN
+#define MAXSECRETLEN                    256     /* max length of password or secret */
+#endif
+
+#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_GEN_ICMP==1: Generate checksums in software for outgoing ICMP packets.
+ */
+#ifndef CHECKSUM_GEN_ICMP
+#define CHECKSUM_GEN_ICMP               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
+
+/**
+ * LWIP_CHECKSUM_ON_COPY==1: Calculate checksum when copying data from
+ * application buffers to pbufs.
+ */
+#ifndef LWIP_CHECKSUM_ON_COPY
+#define LWIP_CHECKSUM_ON_COPY           0
+#endif
+
+/*
+   ---------------------------------------
+   ---------- Hook options ---------------
+   ---------------------------------------
+*/
+
+/* Hooks are undefined by default, define them to a function if you need them. */
+
+/**
+ * LWIP_HOOK_IP4_INPUT(pbuf, input_netif):
+ * - called from ip_input() (IPv4)
+ * - pbuf: received struct pbuf passed to ip_input()
+ * - input_netif: struct netif on which the packet has been received
+ * Return values:
+ * - 0: Hook has not consumed the packet, packet is processed as normal
+ * - != 0: Hook has consumed the packet.
+ * If the hook consumed the packet, 'pbuf' is in the responsibility of the hook
+ * (i.e. free it when done).
+ */
+
+/**
+ * LWIP_HOOK_IP4_ROUTE(dest):
+ * - called from ip_route() (IPv4)
+ * - dest: destination IPv4 address
+ * Returns the destination netif or NULL if no destination netif is found. In
+ * that case, ip_route() continues as normal.
+ */
+
+/*
+   ---------------------------------------
+   ---------- 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_ALL
+#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
+
+/**
+ * TIMERS_DEBUG: Enable debugging in timers.c.
+ */
+#ifndef TIMERS_DEBUG
+#define TIMERS_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 /* __LWIPOPT_H__ */