1 /**
2  * @file
3  *
4  * lwIP Options Configuration
5  */
6 
7 /*
8  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without modification,
12  * are permitted provided that the following conditions are met:
13  *
14  * 1. Redistributions of source code must retain the above copyright notice,
15  *    this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright notice,
17  *    this list of conditions and the following disclaimer in the documentation
18  *    and/or other materials provided with the distribution.
19  * 3. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
25  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
27  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
30  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
31  * OF SUCH DAMAGE.
32  *
33  * This file is part of the lwIP TCP/IP stack.
34  *
35  * Author: Adam Dunkels <adam@sics.se>
36  *
37  */
38 
39 /*
40  * NOTE: || defined __DOXYGEN__ is a workaround for doxygen bug -
41  * without this, doxygen does not see the actual #define
42  */
43 
44 #if !defined LWIP_HDR_OPT_H
45 #define LWIP_HDR_OPT_H
46 
47 /*
48  * Include user defined options first. Anything not defined in these files
49  * will be set to standard values. Override anything you don't like!
50  */
51 #include "lwipopts.h"
52 #include "lwip/debug.h"
53 
54 /**
55  * @defgroup lwip_opts Options (lwipopts.h)
56  * @ingroup lwip
57  *
58  * @defgroup lwip_opts_debug Debugging
59  * @ingroup lwip_opts
60  *
61  * @defgroup lwip_opts_infrastructure Infrastructure
62  * @ingroup lwip_opts
63  *
64  * @defgroup lwip_opts_callback Callback-style APIs
65  * @ingroup lwip_opts
66  *
67  * @defgroup lwip_opts_threadsafe_apis Thread-safe APIs
68  * @ingroup lwip_opts
69  */
70 
71  /*
72    ------------------------------------
73    -------------- NO SYS --------------
74    ------------------------------------
75 */
76 /**
77  * @defgroup lwip_opts_nosys NO_SYS
78  * @ingroup lwip_opts_infrastructure
79  * @{
80  */
81 /**
82  * NO_SYS==1: Use lwIP without OS-awareness (no thread, semaphores, mutexes or
83  * mboxes). This means threaded APIs cannot be used (socket, netconn,
84  * i.e. everything in the 'api' folder), only the callback-style raw API is
85  * available (and you have to watch out for yourself that you don't access
86  * lwIP functions/structures from more than one context at a time!)
87  */
88 #if !defined NO_SYS || defined __DOXYGEN__
89 #define NO_SYS                          0
90 #endif
91 /**
92  * @}
93  */
94 
95 /**
96  * @defgroup lwip_opts_timers Timers
97  * @ingroup lwip_opts_infrastructure
98  * @{
99  */
100 /**
101  * LWIP_TIMERS==0: Drop support for sys_timeout and lwip-internal cyclic timers.
102  * (the array of lwip-internal cyclic timers is still provided)
103  * (check NO_SYS_NO_TIMERS for compatibility to old versions)
104  */
105 #if !defined LWIP_TIMERS || defined __DOXYGEN__
106 #ifdef NO_SYS_NO_TIMERS
107 #define LWIP_TIMERS                     (!NO_SYS || (NO_SYS && !NO_SYS_NO_TIMERS))
108 #else
109 #define LWIP_TIMERS                     1
110 #endif
111 #endif
112 
113 /**
114  * LWIP_TIMERS_CUSTOM==1: Provide your own timer implementation.
115  * Function prototypes in timeouts.h and the array of lwip-internal cyclic timers
116  * are still included, but the implementation is not. The following functions
117  * will be required: sys_timeouts_init(), sys_timeout(), sys_untimeout(),
118  *                   sys_timeouts_mbox_fetch()
119  */
120 #if !defined LWIP_TIMERS_CUSTOM || defined __DOXYGEN__
121 #define LWIP_TIMERS_CUSTOM              0
122 #endif
123 /**
124  * @}
125  */
126 
127 /**
128  * @defgroup lwip_opts_memcpy memcpy
129  * @ingroup lwip_opts_infrastructure
130  * @{
131  */
132 /**
133  * MEMCPY: override this if you have a faster implementation at hand than the
134  * one included in your C library
135  */
136 #if !defined MEMCPY || defined __DOXYGEN__
137 #define MEMCPY(dst,src,len)             memcpy(dst,src,len)
138 #endif
139 
140 /**
141  * SMEMCPY: override this with care! Some compilers (e.g. gcc) can inline a
142  * call to memcpy() if the length is known at compile time and is small.
143  */
144 #if !defined SMEMCPY || defined __DOXYGEN__
145 #define SMEMCPY(dst,src,len)            memcpy(dst,src,len)
146 #endif
147 
148 /**
149  * MEMMOVE: override this if you have a faster implementation at hand than the
150  * one included in your C library.  lwIP currently uses MEMMOVE only when IPv6
151  * fragmentation support is enabled.
152  */
153 #if !defined MEMMOVE || defined __DOXYGEN__
154 #define MEMMOVE(dst,src,len)            memmove(dst,src,len)
155 #endif
156 /**
157  * @}
158  */
159 
160 /*
161    ------------------------------------
162    ----------- Core locking -----------
163    ------------------------------------
164 */
165 /**
166  * @defgroup lwip_opts_lock Core locking and MPU
167  * @ingroup lwip_opts_infrastructure
168  * @{
169  */
170 /**
171  * LWIP_MPU_COMPATIBLE: enables special memory management mechanism
172  * which makes lwip able to work on MPU (Memory Protection Unit) system
173  * by not passing stack-pointers to other threads
174  * (this decreases performance as memory is allocated from pools instead
175  * of keeping it on the stack)
176  */
177 #if !defined LWIP_MPU_COMPATIBLE || defined __DOXYGEN__
178 #define LWIP_MPU_COMPATIBLE             0
179 #endif
180 
181 /**
182  * LWIP_TCPIP_CORE_LOCKING
183  * Creates a global mutex that is held during TCPIP thread operations.
184  * Can be locked by client code to perform lwIP operations without changing
185  * into TCPIP thread using callbacks. See LOCK_TCPIP_CORE() and
186  * UNLOCK_TCPIP_CORE().
187  * Your system should provide mutexes supporting priority inversion to use this.
188  */
189 #if !defined LWIP_TCPIP_CORE_LOCKING || defined __DOXYGEN__
190 #define LWIP_TCPIP_CORE_LOCKING         1
191 #endif
192 
193 /**
194  * LWIP_TCPIP_CORE_LOCKING_INPUT: when LWIP_TCPIP_CORE_LOCKING is enabled,
195  * this lets tcpip_input() grab the mutex for input packets as well,
196  * instead of allocating a message and passing it to tcpip_thread.
197  *
198  * ATTENTION: this does not work when tcpip_input() is called from
199  * interrupt context!
200  */
201 #if !defined LWIP_TCPIP_CORE_LOCKING_INPUT || defined __DOXYGEN__
202 #define LWIP_TCPIP_CORE_LOCKING_INPUT   0
203 #endif
204 
205 /**
206  * SYS_LIGHTWEIGHT_PROT==1: enable inter-task protection (and task-vs-interrupt
207  * protection) for certain critical regions during buffer allocation, deallocation
208  * and memory allocation and deallocation.
209  * ATTENTION: This is required when using lwIP from more than one context! If
210  * you disable this, you must be sure what you are doing!
211  */
212 #if !defined SYS_LIGHTWEIGHT_PROT || defined __DOXYGEN__
213 #define SYS_LIGHTWEIGHT_PROT            1
214 #endif
215 
216 /**
217  * Macro/function to check whether lwIP's threading/locking
218  * requirements are satisfied during current function call.
219  * This macro usually calls a function that is implemented in the OS-dependent
220  * sys layer and performs the following checks:
221  * - Not in ISR (this should be checked for NO_SYS==1, too!)
222  * - If @ref LWIP_TCPIP_CORE_LOCKING = 1: TCPIP core lock is held
223  * - If @ref LWIP_TCPIP_CORE_LOCKING = 0: function is called from TCPIP thread
224  * @see @ref multithreading
225  */
226 #if !defined LWIP_ASSERT_CORE_LOCKED || defined __DOXYGEN__
227 #define LWIP_ASSERT_CORE_LOCKED()
228 #endif
229 
230 
231 /**
232  * @}
233  */
234 
235 /*
236    ------------------------------------
237    ---------- Memory options ----------
238    ------------------------------------
239 */
240 /**
241  * @defgroup lwip_opts_mem Heap and memory pools
242  * @ingroup lwip_opts_infrastructure
243  * @{
244  */
245 /**
246  * MEM_LIBC_MALLOC==1: Use malloc/free/realloc provided by your C-library
247  * instead of the lwip internal allocator. Can save code size if you
248  * already use it.
249  */
250 #if !defined MEM_LIBC_MALLOC || defined __DOXYGEN__
251 #define MEM_LIBC_MALLOC                 0
252 #endif
253 
254 /**
255  * MEMP_MEM_MALLOC==1: Use mem_malloc/mem_free instead of the lwip pool allocator.
256  * Especially useful with MEM_LIBC_MALLOC but handle with care regarding execution
257  * speed (heap alloc can be much slower than pool alloc) and usage from interrupts
258  * (especially if your netif driver allocates PBUF_POOL pbufs for received frames
259  * from interrupt)!
260  * ATTENTION: Currently, this uses the heap for ALL pools (also for private pools,
261  * not only for internal pools defined in memp_std.h)!
262  */
263 #if !defined MEMP_MEM_MALLOC || defined __DOXYGEN__
264 #define MEMP_MEM_MALLOC                 0
265 #endif
266 
267 /**
268  * MEMP_MEM_INIT==1: Force use of memset to initialize pool memory.
269  * Useful if pool are moved in uninitialized section of memory. This will ensure
270  * default values in pcbs struct are well initialized in all conditions.
271  */
272 #if !defined MEMP_MEM_INIT || defined __DOXYGEN__
273 #define MEMP_MEM_INIT                   0
274 #endif
275 
276 /**
277  * MEM_ALIGNMENT: should be set to the alignment of the CPU
278  *    4 byte alignment -> \#define MEM_ALIGNMENT 4
279  *    2 byte alignment -> \#define MEM_ALIGNMENT 2
280  */
281 #if !defined MEM_ALIGNMENT || defined __DOXYGEN__
282 #define MEM_ALIGNMENT                   1
283 #endif
284 
285 /**
286  * MEM_SIZE: the size of the heap memory. If the application will send
287  * a lot of data that needs to be copied, this should be set high.
288  */
289 #if !defined MEM_SIZE || defined __DOXYGEN__
290 #define MEM_SIZE                        1600
291 #endif
292 
293 /**
294  * MEMP_OVERFLOW_CHECK: memp overflow protection reserves a configurable
295  * amount of bytes before and after each memp element in every pool and fills
296  * it with a prominent default value.
297  *    MEMP_OVERFLOW_CHECK == 0 no checking
298  *    MEMP_OVERFLOW_CHECK == 1 checks each element when it is freed
299  *    MEMP_OVERFLOW_CHECK >= 2 checks each element in every pool every time
300  *      memp_malloc() or memp_free() is called (useful but slow!)
301  */
302 #if !defined MEMP_OVERFLOW_CHECK || defined __DOXYGEN__
303 #define MEMP_OVERFLOW_CHECK             0
304 #endif
305 
306 /**
307  * MEMP_SANITY_CHECK==1: run a sanity check after each memp_free() to make
308  * sure that there are no cycles in the linked lists.
309  */
310 #if !defined MEMP_SANITY_CHECK || defined __DOXYGEN__
311 #define MEMP_SANITY_CHECK               0
312 #endif
313 
314 /**
315  * MEM_OVERFLOW_CHECK: mem overflow protection reserves a configurable
316  * amount of bytes before and after each heap allocation chunk and fills
317  * it with a prominent default value.
318  *    MEM_OVERFLOW_CHECK == 0 no checking
319  *    MEM_OVERFLOW_CHECK == 1 checks each element when it is freed
320  *    MEM_OVERFLOW_CHECK >= 2 checks all heap elements every time
321  *      mem_malloc() or mem_free() is called (useful but slow!)
322  */
323 #if !defined MEM_OVERFLOW_CHECK || defined __DOXYGEN__
324 #define MEM_OVERFLOW_CHECK              0
325 #endif
326 
327 /**
328  * MEM_SANITY_CHECK==1: run a sanity check after each mem_free() to make
329  * sure that the linked list of heap elements is not corrupted.
330  */
331 #if !defined MEM_SANITY_CHECK || defined __DOXYGEN__
332 #define MEM_SANITY_CHECK                0
333 #endif
334 
335 /**
336  * MEM_USE_POOLS==1: Use an alternative to malloc() by allocating from a set
337  * of memory pools of various sizes. When mem_malloc is called, an element of
338  * the smallest pool that can provide the length needed is returned.
339  * To use this, MEMP_USE_CUSTOM_POOLS also has to be enabled.
340  */
341 #if !defined MEM_USE_POOLS || defined __DOXYGEN__
342 #define MEM_USE_POOLS                   0
343 #endif
344 
345 /**
346  * MEM_USE_POOLS_TRY_BIGGER_POOL==1: if one malloc-pool is empty, try the next
347  * bigger pool - WARNING: THIS MIGHT WASTE MEMORY but it can make a system more
348  * reliable. */
349 #if !defined MEM_USE_POOLS_TRY_BIGGER_POOL || defined __DOXYGEN__
350 #define MEM_USE_POOLS_TRY_BIGGER_POOL   0
351 #endif
352 
353 /**
354  * MEMP_USE_CUSTOM_POOLS==1: whether to include a user file lwippools.h
355  * that defines additional pools beyond the "standard" ones required
356  * by lwIP. If you set this to 1, you must have lwippools.h in your
357  * include path somewhere.
358  */
359 #if !defined MEMP_USE_CUSTOM_POOLS || defined __DOXYGEN__
360 #define MEMP_USE_CUSTOM_POOLS           0
361 #endif
362 
363 /**
364  * Set this to 1 if you want to free PBUF_RAM pbufs (or call mem_free()) from
365  * interrupt context (or another context that doesn't allow waiting for a
366  * semaphore).
367  * If set to 1, mem_malloc will be protected by a semaphore and SYS_ARCH_PROTECT,
368  * while mem_free will only use SYS_ARCH_PROTECT. mem_malloc SYS_ARCH_UNPROTECTs
369  * with each loop so that mem_free can run.
370  *
371  * ATTENTION: As you can see from the above description, this leads to dis-/
372  * enabling interrupts often, which can be slow! Also, on low memory, mem_malloc
373  * can need longer.
374  *
375  * If you don't want that, at least for NO_SYS=0, you can still use the following
376  * functions to enqueue a deallocation call which then runs in the tcpip_thread
377  * context:
378  * - pbuf_free_callback(p);
379  * - mem_free_callback(m);
380  */
381 #if !defined LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT || defined __DOXYGEN__
382 #define LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT 0
383 #endif
384 /**
385  * @}
386  */
387 
388 /*
389    ------------------------------------------------
390    ---------- Internal Memory Pool Sizes ----------
391    ------------------------------------------------
392 */
393 /**
394  * @defgroup lwip_opts_memp Internal memory pools
395  * @ingroup lwip_opts_infrastructure
396  * @{
397  */
398 /**
399  * MEMP_NUM_PBUF: the number of memp struct pbufs (used for PBUF_ROM and PBUF_REF).
400  * If the application sends a lot of data out of ROM (or other static memory),
401  * this should be set high.
402  */
403 #if !defined MEMP_NUM_PBUF || defined __DOXYGEN__
404 #define MEMP_NUM_PBUF                   16
405 #endif
406 
407 /**
408  * MEMP_NUM_RAW_PCB: Number of raw connection PCBs
409  * (requires the LWIP_RAW option)
410  */
411 #if !defined MEMP_NUM_RAW_PCB || defined __DOXYGEN__
412 #define MEMP_NUM_RAW_PCB                4
413 #endif
414 
415 /**
416  * MEMP_NUM_UDP_PCB: the number of UDP protocol control blocks. One
417  * per active UDP "connection".
418  * (requires the LWIP_UDP option)
419  */
420 #if !defined MEMP_NUM_UDP_PCB || defined __DOXYGEN__
421 #define MEMP_NUM_UDP_PCB                4
422 #endif
423 
424 /**
425  * MEMP_NUM_TCP_PCB: the number of simultaneously active TCP connections.
426  * (requires the LWIP_TCP option)
427  */
428 #if !defined MEMP_NUM_TCP_PCB || defined __DOXYGEN__
429 #define MEMP_NUM_TCP_PCB                5
430 #endif
431 
432 /**
433  * MEMP_NUM_TCP_PCB_LISTEN: the number of listening TCP connections.
434  * (requires the LWIP_TCP option)
435  */
436 #if !defined MEMP_NUM_TCP_PCB_LISTEN || defined __DOXYGEN__
437 #define MEMP_NUM_TCP_PCB_LISTEN         8
438 #endif
439 
440 /**
441  * MEMP_NUM_TCP_SEG: the number of simultaneously queued TCP segments.
442  * (requires the LWIP_TCP option)
443  */
444 #if !defined MEMP_NUM_TCP_SEG || defined __DOXYGEN__
445 #define MEMP_NUM_TCP_SEG                16
446 #endif
447 
448 /**
449  * MEMP_NUM_ALTCP_PCB: the number of simultaneously active altcp layer pcbs.
450  * (requires the LWIP_ALTCP option)
451  * Connections with multiple layers require more than one altcp_pcb (e.g. TLS
452  * over TCP requires 2 altcp_pcbs, one for TLS and one for TCP).
453  */
454 #if !defined MEMP_NUM_ALTCP_PCB || defined __DOXYGEN__
455 #define MEMP_NUM_ALTCP_PCB              MEMP_NUM_TCP_PCB
456 #endif
457 
458 /**
459  * MEMP_NUM_REASSDATA: the number of IP packets simultaneously queued for
460  * reassembly (whole packets, not fragments!)
461  */
462 #if !defined MEMP_NUM_REASSDATA || defined __DOXYGEN__
463 #define MEMP_NUM_REASSDATA              5
464 #endif
465 
466 /**
467  * MEMP_NUM_FRAG_PBUF: the number of IP fragments simultaneously sent
468  * (fragments, not whole packets!).
469  * This is only used with LWIP_NETIF_TX_SINGLE_PBUF==0 and only has to be > 1
470  * with DMA-enabled MACs where the packet is not yet sent when netif->output
471  * returns.
472  */
473 #if !defined MEMP_NUM_FRAG_PBUF || defined __DOXYGEN__
474 #define MEMP_NUM_FRAG_PBUF              15
475 #endif
476 
477 /**
478  * MEMP_NUM_ARP_QUEUE: the number of simultaneously queued outgoing
479  * packets (pbufs) that are waiting for an ARP request (to resolve
480  * their destination address) to finish.
481  * (requires the ARP_QUEUEING option)
482  */
483 #if !defined MEMP_NUM_ARP_QUEUE || defined __DOXYGEN__
484 #define MEMP_NUM_ARP_QUEUE              30
485 #endif
486 
487 /**
488  * MEMP_NUM_IGMP_GROUP: The number of multicast groups whose network interfaces
489  * can be members at the same time (one per netif - allsystems group -, plus one
490  * per netif membership).
491  * (requires the LWIP_IGMP option)
492  */
493 #if !defined MEMP_NUM_IGMP_GROUP || defined __DOXYGEN__
494 #define MEMP_NUM_IGMP_GROUP             8
495 #endif
496 
497 /**
498  * The number of sys timeouts used by the core stack (not apps)
499  * The default number of timeouts is calculated here for all enabled modules.
500  */
501 #define LWIP_NUM_SYS_TIMEOUT_INTERNAL   (LWIP_TCP + IP_REASSEMBLY + LWIP_ARP + (2*LWIP_DHCP) + LWIP_ACD + LWIP_IGMP + LWIP_DNS + PPP_NUM_TIMEOUTS + (LWIP_IPV6 * (1 + LWIP_IPV6_REASS + LWIP_IPV6_MLD + LWIP_IPV6_DHCP6)))
502 
503 /**
504  * MEMP_NUM_SYS_TIMEOUT: the number of simultaneously active timeouts.
505  * The default number of timeouts is calculated here for all enabled modules.
506  * The formula expects settings to be either '0' or '1'.
507  */
508 #if !defined MEMP_NUM_SYS_TIMEOUT || defined __DOXYGEN__
509 #define MEMP_NUM_SYS_TIMEOUT            LWIP_NUM_SYS_TIMEOUT_INTERNAL
510 #endif
511 
512 /**
513  * MEMP_NUM_NETBUF: the number of struct netbufs.
514  * (only needed if you use the sequential API, like api_lib.c)
515  */
516 #if !defined MEMP_NUM_NETBUF || defined __DOXYGEN__
517 #define MEMP_NUM_NETBUF                 2
518 #endif
519 
520 /**
521  * MEMP_NUM_NETCONN: the number of struct netconns.
522  * (only needed if you use the sequential API, like api_lib.c)
523  */
524 #if !defined MEMP_NUM_NETCONN || defined __DOXYGEN__
525 #define MEMP_NUM_NETCONN                4
526 #endif
527 
528 /**
529  * MEMP_NUM_SELECT_CB: the number of struct lwip_select_cb.
530  * (Only needed if you have LWIP_MPU_COMPATIBLE==1 and use the socket API.
531  * In that case, you need one per thread calling lwip_select.)
532  */
533 #if !defined MEMP_NUM_SELECT_CB || defined __DOXYGEN__
534 #define MEMP_NUM_SELECT_CB              4
535 #endif
536 
537 /**
538  * MEMP_NUM_TCPIP_MSG_API: the number of struct tcpip_msg, which are used
539  * for callback/timeout API communication.
540  * (only needed if you use tcpip.c)
541  */
542 #if !defined MEMP_NUM_TCPIP_MSG_API || defined __DOXYGEN__
543 #define MEMP_NUM_TCPIP_MSG_API          8
544 #endif
545 
546 /**
547  * MEMP_NUM_TCPIP_MSG_INPKT: the number of struct tcpip_msg, which are used
548  * for incoming packets.
549  * (only needed if you use tcpip.c)
550  */
551 #if !defined MEMP_NUM_TCPIP_MSG_INPKT || defined __DOXYGEN__
552 #define MEMP_NUM_TCPIP_MSG_INPKT        8
553 #endif
554 
555 /**
556  * MEMP_NUM_NETDB: the number of concurrently running lwip_addrinfo() calls
557  * (before freeing the corresponding memory using lwip_freeaddrinfo()).
558  */
559 #if !defined MEMP_NUM_NETDB || defined __DOXYGEN__
560 #define MEMP_NUM_NETDB                  1
561 #endif
562 
563 /**
564  * MEMP_NUM_LOCALHOSTLIST: the number of host entries in the local host list
565  * if DNS_LOCAL_HOSTLIST_IS_DYNAMIC==1.
566  */
567 #if !defined MEMP_NUM_LOCALHOSTLIST || defined __DOXYGEN__
568 #define MEMP_NUM_LOCALHOSTLIST          1
569 #endif
570 
571 /**
572  * PBUF_POOL_SIZE: the number of buffers in the pbuf pool.
573  */
574 #if !defined PBUF_POOL_SIZE || defined __DOXYGEN__
575 #define PBUF_POOL_SIZE                  16
576 #endif
577 
578 /** MEMP_NUM_API_MSG: the number of concurrently active calls to various
579  * socket, netconn, and tcpip functions
580  */
581 #if !defined MEMP_NUM_API_MSG || defined __DOXYGEN__
582 #define MEMP_NUM_API_MSG                MEMP_NUM_TCPIP_MSG_API
583 #endif
584 
585 /** MEMP_NUM_DNS_API_MSG: the number of concurrently active calls to netconn_gethostbyname
586  */
587 #if !defined MEMP_NUM_DNS_API_MSG || defined __DOXYGEN__
588 #define MEMP_NUM_DNS_API_MSG            MEMP_NUM_TCPIP_MSG_API
589 #endif
590 
591 /** MEMP_NUM_SOCKET_SETGETSOCKOPT_DATA: the number of concurrently active calls
592  * to getsockopt/setsockopt
593  */
594 #if !defined MEMP_NUM_SOCKET_SETGETSOCKOPT_DATA || defined __DOXYGEN__
595 #define MEMP_NUM_SOCKET_SETGETSOCKOPT_DATA MEMP_NUM_TCPIP_MSG_API
596 #endif
597 
598 /** MEMP_NUM_NETIFAPI_MSG: the number of concurrently active calls to the
599  * netifapi functions
600  */
601 #if !defined MEMP_NUM_NETIFAPI_MSG || defined __DOXYGEN__
602 #define MEMP_NUM_NETIFAPI_MSG           MEMP_NUM_TCPIP_MSG_API
603 #endif
604 /**
605  * @}
606  */
607 
608 /*
609    ---------------------------------
610    ---------- ARP options ----------
611    ---------------------------------
612 */
613 /**
614  * @defgroup lwip_opts_arp ARP
615  * @ingroup lwip_opts_ipv4
616  * @{
617  */
618 /**
619  * LWIP_ARP==1: Enable ARP functionality.
620  */
621 #if !defined LWIP_ARP || defined __DOXYGEN__
622 #define LWIP_ARP                        1
623 #endif
624 
625 /**
626  * ARP_TABLE_SIZE: Number of active MAC-IP address pairs cached.
627  */
628 #if !defined ARP_TABLE_SIZE || defined __DOXYGEN__
629 #define ARP_TABLE_SIZE                  10
630 #endif
631 
632 /** the time an ARP entry stays valid after its last update,
633  *  for ARP_TMR_INTERVAL = 1000, this is
634  *  (60 * 5) seconds = 5 minutes.
635  */
636 #if !defined ARP_MAXAGE || defined __DOXYGEN__
637 #define ARP_MAXAGE                      300
638 #endif
639 
640 /**
641  * ARP_QUEUEING==1: Multiple outgoing packets are queued during hardware address
642  * resolution. By default, only the most recent packet is queued per IP address.
643  * This is sufficient for most protocols and mainly reduces TCP connection
644  * startup time. Set this to 1 if you know your application sends more than one
645  * packet in a row to an IP address that is not in the ARP cache.
646  */
647 #if !defined ARP_QUEUEING || defined __DOXYGEN__
648 #define ARP_QUEUEING                    0
649 #endif
650 
651 /** The maximum number of packets which may be queued for each
652  *  unresolved address by other network layers. Defaults to 3, 0 means disabled.
653  *  Old packets are dropped, new packets are queued.
654  */
655 #if !defined ARP_QUEUE_LEN || defined __DOXYGEN__
656 #define ARP_QUEUE_LEN                   3
657 #endif
658 
659 /**
660  * ETHARP_SUPPORT_VLAN==1: support receiving and sending ethernet packets with
661  * VLAN header. See the description of LWIP_HOOK_VLAN_CHECK and
662  * LWIP_HOOK_VLAN_SET hooks to check/set VLAN headers.
663  * Additionally, you can define ETHARP_VLAN_CHECK to an u16_t VLAN ID to check.
664  * If ETHARP_VLAN_CHECK is defined, only VLAN-traffic for this VLAN is accepted.
665  * If ETHARP_VLAN_CHECK is not defined, all traffic is accepted.
666  * Alternatively, define a function/define ETHARP_VLAN_CHECK_FN(eth_hdr, vlan)
667  * that returns 1 to accept a packet or 0 to drop a packet.
668  */
669 #if !defined ETHARP_SUPPORT_VLAN || defined __DOXYGEN__
670 #define ETHARP_SUPPORT_VLAN             0
671 #endif
672 
673 /**
674  * LWIP_VLAN_PCP==1: Enable outgoing VLAN taggning of frames on a per-PCB basis
675  * for QoS purposes. With this feature enabled, each PCB has a new variable:
676  * "netif_hints.tci" (Tag Control Identifier).
677  * The TCI contains three fields: VID, CFI and PCP.
678  * - VID is the VLAN ID, which should be set to zero.
679  * - The "CFI" bit is used to enable or disable VLAN tags for the PCB.
680  * - PCP (Priority Code Point) is a 3 bit field used for Ethernet level QoS.
681  * See pcb_tci_*() functions to get/set/clear this.
682  */
683 #ifndef LWIP_VLAN_PCP
684 #define LWIP_VLAN_PCP                   0
685 #endif
686 
687 /** LWIP_ETHERNET==1: enable ethernet support even though ARP might be disabled
688  */
689 #if !defined LWIP_ETHERNET || defined __DOXYGEN__
690 #define LWIP_ETHERNET                   LWIP_ARP
691 #endif
692 
693 /** ETH_PAD_SIZE: number of bytes added before the ethernet header to ensure
694  * alignment of payload after that header. Since the header is 14 bytes long,
695  * without this padding e.g. addresses in the IP header will not be aligned
696  * on a 32-bit boundary, so setting this to 2 can speed up 32-bit-platforms.
697  */
698 #if !defined ETH_PAD_SIZE || defined __DOXYGEN__
699 #define ETH_PAD_SIZE                    0
700 #endif
701 
702 /** ETHARP_SUPPORT_STATIC_ENTRIES==1: enable code to support static ARP table
703  * entries (using etharp_add_static_entry/etharp_remove_static_entry).
704  */
705 #if !defined ETHARP_SUPPORT_STATIC_ENTRIES || defined __DOXYGEN__
706 #define ETHARP_SUPPORT_STATIC_ENTRIES   0
707 #endif
708 
709 /** ETHARP_TABLE_MATCH_NETIF==1: Match netif for ARP table entries.
710  * If disabled, duplicate IP address on multiple netifs are not supported
711  * (but this should only occur for AutoIP).
712  */
713 #if !defined ETHARP_TABLE_MATCH_NETIF || defined __DOXYGEN__
714 #define ETHARP_TABLE_MATCH_NETIF        !LWIP_SINGLE_NETIF
715 #endif
716 /**
717  * @}
718  */
719 
720 /*
721    --------------------------------
722    ---------- IP options ----------
723    --------------------------------
724 */
725 /**
726  * @defgroup lwip_opts_ipv4 IPv4
727  * @ingroup lwip_opts
728  * @{
729  */
730 /**
731  * LWIP_IPV4==1: Enable IPv4
732  */
733 #if !defined LWIP_IPV4 || defined __DOXYGEN__
734 #define LWIP_IPV4                       1
735 #endif
736 
737 /**
738  * IP_FORWARD==1: Enables the ability to forward IP packets across network
739  * interfaces. If you are going to run lwIP on a device with only one network
740  * interface, define this to 0.
741  */
742 #if !defined IP_FORWARD || defined __DOXYGEN__
743 #define IP_FORWARD                      0
744 #endif
745 
746 /**
747  * IP_REASSEMBLY==1: Reassemble incoming fragmented IP packets. Note that
748  * this option does not affect outgoing packet sizes, which can be controlled
749  * via IP_FRAG.
750  */
751 #if !defined IP_REASSEMBLY || defined __DOXYGEN__
752 #define IP_REASSEMBLY                   1
753 #endif
754 
755 /**
756  * IP_FRAG==1: Fragment outgoing IP packets if their size exceeds MTU. Note
757  * that this option does not affect incoming packet sizes, which can be
758  * controlled via IP_REASSEMBLY.
759  */
760 #if !defined IP_FRAG || defined __DOXYGEN__
761 #define IP_FRAG                         1
762 #endif
763 
764 #if !LWIP_IPV4
765 /* disable IPv4 extensions when IPv4 is disabled */
766 #undef IP_FORWARD
767 #define IP_FORWARD                      0
768 #undef IP_REASSEMBLY
769 #define IP_REASSEMBLY                   0
770 #undef IP_FRAG
771 #define IP_FRAG                         0
772 #endif /* !LWIP_IPV4 */
773 
774 /**
775  * IP_OPTIONS_ALLOWED: Defines the behavior for IP options.
776  *      IP_OPTIONS_ALLOWED==0: All packets with IP options are dropped.
777  *      IP_OPTIONS_ALLOWED==1: IP options are allowed (but not parsed).
778  */
779 #if !defined IP_OPTIONS_ALLOWED || defined __DOXYGEN__
780 #define IP_OPTIONS_ALLOWED              1
781 #endif
782 
783 /**
784  * IP_REASS_MAXAGE: Maximum time (in multiples of IP_TMR_INTERVAL - so seconds, normally)
785  * a fragmented IP packet waits for all fragments to arrive. If not all fragments arrived
786  * in this time, the whole packet is discarded.
787  */
788 #if !defined IP_REASS_MAXAGE || defined __DOXYGEN__
789 #define IP_REASS_MAXAGE                 15
790 #endif
791 
792 /**
793  * IP_REASS_MAX_PBUFS: Total maximum amount of pbufs waiting to be reassembled.
794  * Since the received pbufs are enqueued, be sure to configure
795  * PBUF_POOL_SIZE > IP_REASS_MAX_PBUFS so that the stack is still able to receive
796  * packets even if the maximum amount of fragments is enqueued for reassembly!
797  * When IPv4 *and* IPv6 are enabled, this even changes to
798  * (PBUF_POOL_SIZE > 2 * IP_REASS_MAX_PBUFS)!
799  */
800 #if !defined IP_REASS_MAX_PBUFS || defined __DOXYGEN__
801 #define IP_REASS_MAX_PBUFS              10
802 #endif
803 
804 /**
805  * IP_DEFAULT_TTL: Default value for Time-To-Live used by transport layers.
806  */
807 #if !defined IP_DEFAULT_TTL || defined __DOXYGEN__
808 #define IP_DEFAULT_TTL                  255
809 #endif
810 
811 /**
812  * IP_SOF_BROADCAST=1: Use the SOF_BROADCAST field to enable broadcast
813  * filter per pcb on udp and raw send operations. To enable broadcast filter
814  * on recv operations, you also have to set IP_SOF_BROADCAST_RECV=1.
815  */
816 #if !defined IP_SOF_BROADCAST || defined __DOXYGEN__
817 #define IP_SOF_BROADCAST                0
818 #endif
819 
820 /**
821  * IP_SOF_BROADCAST_RECV (requires IP_SOF_BROADCAST=1) enable the broadcast
822  * filter on recv operations.
823  */
824 #if !defined IP_SOF_BROADCAST_RECV || defined __DOXYGEN__
825 #define IP_SOF_BROADCAST_RECV           0
826 #endif
827 
828 /**
829  * IP_FORWARD_ALLOW_TX_ON_RX_NETIF==1: allow ip_forward() to send packets back
830  * out on the netif where it was received. This should only be used for
831  * wireless networks.
832  * ATTENTION: When this is 1, make sure your netif driver correctly marks incoming
833  * link-layer-broadcast/multicast packets as such using the corresponding pbuf flags!
834  */
835 #if !defined IP_FORWARD_ALLOW_TX_ON_RX_NETIF || defined __DOXYGEN__
836 #define IP_FORWARD_ALLOW_TX_ON_RX_NETIF 0
837 #endif
838 /**
839  * @}
840  */
841 
842 /*
843    ----------------------------------
844    ---------- ICMP options ----------
845    ----------------------------------
846 */
847 /**
848  * @defgroup lwip_opts_icmp ICMP
849  * @ingroup lwip_opts_ipv4
850  * @{
851  */
852 /**
853  * LWIP_ICMP==1: Enable ICMP module inside the IP stack.
854  * Be careful, disable that make your product non-compliant to RFC1122
855  */
856 #if !defined LWIP_ICMP || defined __DOXYGEN__
857 #define LWIP_ICMP                       1
858 #endif
859 
860 /**
861  * ICMP_TTL: Default value for Time-To-Live used by ICMP packets.
862  */
863 #if !defined ICMP_TTL || defined __DOXYGEN__
864 #define ICMP_TTL                        IP_DEFAULT_TTL
865 #endif
866 
867 /**
868  * LWIP_BROADCAST_PING==1: respond to broadcast pings (default is unicast only)
869  */
870 #if !defined LWIP_BROADCAST_PING || defined __DOXYGEN__
871 #define LWIP_BROADCAST_PING             0
872 #endif
873 
874 /**
875  * LWIP_MULTICAST_PING==1: respond to multicast pings (default is unicast only)
876  */
877 #if !defined LWIP_MULTICAST_PING || defined __DOXYGEN__
878 #define LWIP_MULTICAST_PING             0
879 #endif
880 /**
881  * @}
882  */
883 
884 /*
885    ---------------------------------
886    ---------- RAW options ----------
887    ---------------------------------
888 */
889 /**
890  * @defgroup lwip_opts_raw RAW
891  * @ingroup lwip_opts_callback
892  * @{
893  */
894 /**
895  * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
896  */
897 #if !defined LWIP_RAW || defined __DOXYGEN__
898 #define LWIP_RAW                        0
899 #endif
900 
901 /**
902  * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
903  */
904 #if !defined RAW_TTL || defined __DOXYGEN__
905 #define RAW_TTL                         IP_DEFAULT_TTL
906 #endif
907 /**
908  * @}
909  */
910 
911 /*
912    ----------------------------------
913    ---------- DHCP options ----------
914    ----------------------------------
915 */
916 /**
917  * @defgroup lwip_opts_dhcp DHCP
918  * @ingroup lwip_opts_ipv4
919  * @{
920  */
921 /**
922  * LWIP_DHCP==1: Enable DHCP module.
923  */
924 #if !defined LWIP_DHCP || defined __DOXYGEN__
925 #define LWIP_DHCP                       0
926 #endif
927 #if !LWIP_IPV4
928 /* disable DHCP when IPv4 is disabled */
929 #undef LWIP_DHCP
930 #define LWIP_DHCP                       0
931 #endif /* !LWIP_IPV4 */
932 
933 /**
934  * LWIP_DHCP_DOES_ACD_CHECK==1: Perform address conflict detection on the dhcp address.
935  */
936 #if !defined LWIP_DHCP_DOES_ACD_CHECK || defined __DOXYGEN__
937 #define LWIP_DHCP_DOES_ACD_CHECK        LWIP_DHCP
938 #endif
939 
940 /**
941  * LWIP_DHCP_BOOTP_FILE==1: Store offered_si_addr and boot_file_name.
942  */
943 #if !defined LWIP_DHCP_BOOTP_FILE || defined __DOXYGEN__
944 #define LWIP_DHCP_BOOTP_FILE            0
945 #endif
946 
947 /**
948  * LWIP_DHCP_GETS_NTP==1: Request NTP servers with discover/select. For each
949  * response packet, an callback is called, which has to be provided by the port:
950  * void dhcp_set_ntp_servers(u8_t num_ntp_servers, ip_addr_t* ntp_server_addrs);
951 */
952 #if !defined LWIP_DHCP_GET_NTP_SRV || defined __DOXYGEN__
953 #define LWIP_DHCP_GET_NTP_SRV           0
954 #endif
955 
956 /**
957  * The maximum of NTP servers requested
958  */
959 #if !defined LWIP_DHCP_MAX_NTP_SERVERS || defined __DOXYGEN__
960 #define LWIP_DHCP_MAX_NTP_SERVERS       1
961 #endif
962 
963 /**
964  * LWIP_DHCP_MAX_DNS_SERVERS > 0: Request DNS servers with discover/select.
965  * DNS servers received in the response are passed to DNS via @ref dns_setserver()
966  * (up to the maximum limit defined here).
967  */
968 #if !defined LWIP_DHCP_MAX_DNS_SERVERS || defined __DOXYGEN__
969 #define LWIP_DHCP_MAX_DNS_SERVERS       DNS_MAX_SERVERS
970 #endif
971 
972 /** LWIP_DHCP_DISCOVER_ADD_HOSTNAME: Set to 1 to include hostname opt in discover packets.
973  * If the hostname is not set in the DISCOVER packet, then some servers might issue an OFFER with hostname
974  * configured and consequently reject the REQUEST with any other hostname.
975  */
976 #if !defined LWIP_DHCP_DISCOVER_ADD_HOSTNAME || defined __DOXYGEN__
977 #define LWIP_DHCP_DISCOVER_ADD_HOSTNAME 0
978 #endif /* LWIP_DHCP_DISCOVER_ADD_HOSTNAME */
979 /**
980  * @}
981  */
982 
983 /*
984    ------------------------------------
985    ---------- AUTOIP options ----------
986    ------------------------------------
987 */
988 /**
989  * @defgroup lwip_opts_autoip AUTOIP
990  * @ingroup lwip_opts_ipv4
991  * @{
992  */
993 /**
994  * LWIP_AUTOIP==1: Enable AUTOIP module.
995  */
996 #if !defined LWIP_AUTOIP || defined __DOXYGEN__
997 #define LWIP_AUTOIP                     0
998 #endif
999 #if !LWIP_IPV4
1000 /* disable AUTOIP when IPv4 is disabled */
1001 #undef LWIP_AUTOIP
1002 #define LWIP_AUTOIP                     0
1003 #endif /* !LWIP_IPV4 */
1004 
1005 /**
1006  * LWIP_DHCP_AUTOIP_COOP==1: Allow DHCP and AUTOIP to be both enabled on
1007  * the same interface at the same time.
1008  */
1009 #if !defined LWIP_DHCP_AUTOIP_COOP || defined __DOXYGEN__
1010 #define LWIP_DHCP_AUTOIP_COOP           0
1011 #endif
1012 
1013 /**
1014  * LWIP_DHCP_AUTOIP_COOP_TRIES: Set to the number of DHCP DISCOVER probes
1015  * that should be sent before falling back on AUTOIP (the DHCP client keeps
1016  * running in this case). This can be set as low as 1 to get an AutoIP address
1017  * very  quickly, but you should be prepared to handle a changing IP address
1018  * when DHCP overrides AutoIP.
1019  */
1020 #if !defined LWIP_DHCP_AUTOIP_COOP_TRIES || defined __DOXYGEN__
1021 #define LWIP_DHCP_AUTOIP_COOP_TRIES     9
1022 #endif
1023 /**
1024  * @}
1025  */
1026 
1027 /*
1028    ------------------------------------
1029    ----------- ACD options ------------
1030    ------------------------------------
1031 */
1032 /**
1033  * @defgroup lwip_opts_acd ACD
1034  * @ingroup lwip_opts_ipv4
1035  * @{
1036  */
1037  /**
1038   * LWIP_ACD==1: Enable ACD module. ACD module is needed when using AUTOIP.
1039   */
1040 #if !defined LWIP_ACD || defined __DOXYGEN__
1041 #define LWIP_ACD                     (LWIP_AUTOIP || LWIP_DHCP_DOES_ACD_CHECK)
1042 #endif
1043 #if !LWIP_IPV4
1044 /* disable ACD when IPv4 is disabled */
1045 #undef LWIP_ACD
1046 #define LWIP_ACD                     0
1047 #endif /* !LWIP_IPV4 */
1048 /**
1049  * @}
1050  */
1051 
1052 /*
1053    ----------------------------------
1054    ----- SNMP MIB2 support      -----
1055    ----------------------------------
1056 */
1057 /**
1058  * @defgroup lwip_opts_mib2 SNMP MIB2 callbacks
1059  * @ingroup lwip_opts_infrastructure
1060  * @{
1061  */
1062 /**
1063  * LWIP_MIB2_CALLBACKS==1: Turn on SNMP MIB2 callbacks.
1064  * Turn this on to get callbacks needed to implement MIB2.
1065  * Usually MIB2_STATS should be enabled, too.
1066  */
1067 #if !defined LWIP_MIB2_CALLBACKS || defined __DOXYGEN__
1068 #define LWIP_MIB2_CALLBACKS             0
1069 #endif
1070 /**
1071  * @}
1072  */
1073 
1074 /*
1075    ----------------------------------
1076    -------- Multicast options -------
1077    ----------------------------------
1078 */
1079 /**
1080  * @defgroup lwip_opts_multicast Multicast
1081  * @ingroup lwip_opts_infrastructure
1082  * @{
1083  */
1084 /**
1085  * LWIP_MULTICAST_TX_OPTIONS==1: Enable multicast TX support like the socket options
1086  * IP_MULTICAST_TTL/IP_MULTICAST_IF/IP_MULTICAST_LOOP, as well as (currently only)
1087  * core support for the corresponding IPv6 options.
1088  */
1089 #if !defined LWIP_MULTICAST_TX_OPTIONS || defined __DOXYGEN__
1090 #define LWIP_MULTICAST_TX_OPTIONS       ((LWIP_IGMP || LWIP_IPV6_MLD) && (LWIP_UDP || LWIP_RAW))
1091 #endif
1092 /**
1093  * @}
1094  */
1095 
1096 /*
1097    ----------------------------------
1098    ---------- IGMP options ----------
1099    ----------------------------------
1100 */
1101 /**
1102  * @defgroup lwip_opts_igmp IGMP
1103  * @ingroup lwip_opts_ipv4
1104  * @{
1105  */
1106 /**
1107  * LWIP_IGMP==1: Turn on IGMP module.
1108  */
1109 #if !defined LWIP_IGMP || defined __DOXYGEN__
1110 #define LWIP_IGMP                       0
1111 #endif
1112 #if !LWIP_IPV4
1113 #undef LWIP_IGMP
1114 #define LWIP_IGMP                       0
1115 #endif
1116 /**
1117  * @}
1118  */
1119 
1120 /*
1121    ----------------------------------
1122    ---------- DNS options -----------
1123    ----------------------------------
1124 */
1125 /**
1126  * @defgroup lwip_opts_dns DNS
1127  * @ingroup lwip_opts_callback
1128  * @{
1129  */
1130 /**
1131  * LWIP_DNS==1: Turn on DNS module. UDP must be available for DNS
1132  * transport.
1133  */
1134 #if !defined LWIP_DNS || defined __DOXYGEN__
1135 #define LWIP_DNS                        0
1136 #endif
1137 
1138 /** DNS maximum number of entries to maintain locally. */
1139 #if !defined DNS_TABLE_SIZE || defined __DOXYGEN__
1140 #define DNS_TABLE_SIZE                  4
1141 #endif
1142 
1143 /** DNS maximum host name length supported in the name table. */
1144 #if !defined DNS_MAX_NAME_LENGTH || defined __DOXYGEN__
1145 #define DNS_MAX_NAME_LENGTH             256
1146 #endif
1147 
1148 /** The maximum of DNS servers
1149  * The first server can be initialized automatically by defining
1150  * DNS_SERVER_ADDRESS(ipaddr), where 'ipaddr' is an 'ip_addr_t*'
1151  */
1152 #if !defined DNS_MAX_SERVERS || defined __DOXYGEN__
1153 #define DNS_MAX_SERVERS                 2
1154 #endif
1155 
1156 /** DNS maximum number of retries when asking for a name, before "timeout". */
1157 #if !defined DNS_MAX_RETRIES || defined __DOXYGEN__
1158 #define DNS_MAX_RETRIES                 4
1159 #endif
1160 
1161 /** DNS do a name checking between the query and the response. */
1162 #if !defined DNS_DOES_NAME_CHECK || defined __DOXYGEN__
1163 #define DNS_DOES_NAME_CHECK             1
1164 #endif
1165 
1166 /** LWIP_DNS_SECURE: controls the security level of the DNS implementation
1167  * Use all DNS security features by default.
1168  * This is overridable but should only be needed by very small targets
1169  * or when using against non standard DNS servers. */
1170 #if !defined LWIP_DNS_SECURE || defined __DOXYGEN__
1171 #define LWIP_DNS_SECURE (LWIP_DNS_SECURE_RAND_XID | LWIP_DNS_SECURE_NO_MULTIPLE_OUTSTANDING | LWIP_DNS_SECURE_RAND_SRC_PORT)
1172 #endif
1173 
1174 /* A list of DNS security features follows */
1175 #define LWIP_DNS_SECURE_RAND_XID                1
1176 #define LWIP_DNS_SECURE_NO_MULTIPLE_OUTSTANDING 2
1177 #define LWIP_DNS_SECURE_RAND_SRC_PORT           4
1178 
1179 /** DNS_LOCAL_HOSTLIST: Implements a local host-to-address list. If enabled, you have to define an initializer:
1180  *  \#define DNS_LOCAL_HOSTLIST_INIT {DNS_LOCAL_HOSTLIST_ELEM("host_ip4", IPADDR4_INIT_BYTES(1,2,3,4)), \
1181  *                                    DNS_LOCAL_HOSTLIST_ELEM("host_ip6", IPADDR6_INIT_HOST(123, 234, 345, 456)}
1182  *
1183  *  Instead, you can also use an external function:
1184  *  \#define DNS_LOOKUP_LOCAL_EXTERN(name, namelen, addr, dns_addrtype) my_lookup_function(name, namelen, addr, dns_addrtype)
1185  *  with function signature:
1186  *  extern err_t my_lookup_function(const char *name, size_t namelen, ip_addr_t *addr, u8_t dns_addrtype)
1187  *  that looks up the IP address and returns ERR_OK if found (LWIP_DNS_ADDRTYPE_xxx is passed in dns_addrtype).
1188  */
1189 #if !defined DNS_LOCAL_HOSTLIST || defined __DOXYGEN__
1190 #define DNS_LOCAL_HOSTLIST              0
1191 #endif /* DNS_LOCAL_HOSTLIST */
1192 
1193 /** If this is turned on, the local host-list can be dynamically changed
1194  *  at runtime. */
1195 #if !defined DNS_LOCAL_HOSTLIST_IS_DYNAMIC || defined __DOXYGEN__
1196 #define DNS_LOCAL_HOSTLIST_IS_DYNAMIC   0
1197 #endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
1198 
1199 /** Set this to 1 to enable querying ".local" names via mDNS
1200  *  using a One-Shot Multicast DNS Query */
1201 #if !defined LWIP_DNS_SUPPORT_MDNS_QUERIES || defined __DOXYGEN__
1202 #define LWIP_DNS_SUPPORT_MDNS_QUERIES   0
1203 #endif
1204 /**
1205  * @}
1206  */
1207 
1208 /*
1209    ---------------------------------
1210    ---------- UDP options ----------
1211    ---------------------------------
1212 */
1213 /**
1214  * @defgroup lwip_opts_udp UDP
1215  * @ingroup lwip_opts_callback
1216  * @{
1217  */
1218 /**
1219  * LWIP_UDP==1: Turn on UDP.
1220  */
1221 #if !defined LWIP_UDP || defined __DOXYGEN__
1222 #define LWIP_UDP                        1
1223 #endif
1224 
1225 /**
1226  * LWIP_UDPLITE==1: Turn on UDP-Lite. (Requires LWIP_UDP)
1227  */
1228 #if !defined LWIP_UDPLITE || defined __DOXYGEN__
1229 #define LWIP_UDPLITE                    0
1230 #endif
1231 
1232 /**
1233  * UDP_TTL: Default Time-To-Live value.
1234  */
1235 #if !defined UDP_TTL || defined __DOXYGEN__
1236 #define UDP_TTL                         IP_DEFAULT_TTL
1237 #endif
1238 
1239 /**
1240  * LWIP_NETBUF_RECVINFO==1: append destination addr and port to every netbuf.
1241  */
1242 #if !defined LWIP_NETBUF_RECVINFO || defined __DOXYGEN__
1243 #define LWIP_NETBUF_RECVINFO            0
1244 #endif
1245 /**
1246  * @}
1247  */
1248 
1249 /*
1250    ---------------------------------
1251    ---------- TCP options ----------
1252    ---------------------------------
1253 */
1254 /**
1255  * @defgroup lwip_opts_tcp TCP
1256  * @ingroup lwip_opts_callback
1257  * @{
1258  */
1259 /**
1260  * LWIP_TCP==1: Turn on TCP.
1261  */
1262 #if !defined LWIP_TCP || defined __DOXYGEN__
1263 #define LWIP_TCP                        1
1264 #endif
1265 
1266 /**
1267  * TCP_TTL: Default Time-To-Live value.
1268  */
1269 #if !defined TCP_TTL || defined __DOXYGEN__
1270 #define TCP_TTL                         IP_DEFAULT_TTL
1271 #endif
1272 
1273 /**
1274  * TCP_WND: The size of a TCP window.  This must be at least
1275  * (2 * TCP_MSS) for things to work well.
1276  * ATTENTION: when using TCP_RCV_SCALE, TCP_WND is the total size
1277  * with scaling applied. Maximum window value in the TCP header
1278  * will be TCP_WND >> TCP_RCV_SCALE
1279  */
1280 #if !defined TCP_WND || defined __DOXYGEN__
1281 #define TCP_WND                         (4 * TCP_MSS)
1282 #endif
1283 
1284 /**
1285  * TCP_MAXRTX: Maximum number of retransmissions of data segments.
1286  */
1287 #if !defined TCP_MAXRTX || defined __DOXYGEN__
1288 #define TCP_MAXRTX                      12
1289 #endif
1290 
1291 /**
1292  * TCP_SYNMAXRTX: Maximum number of retransmissions of SYN segments.
1293  */
1294 #if !defined TCP_SYNMAXRTX || defined __DOXYGEN__
1295 #define TCP_SYNMAXRTX                   6
1296 #endif
1297 
1298 /**
1299  * TCP_QUEUE_OOSEQ==1: TCP will queue segments that arrive out of order.
1300  * Define to 0 if your device is low on memory.
1301  */
1302 #if !defined TCP_QUEUE_OOSEQ || defined __DOXYGEN__
1303 #define TCP_QUEUE_OOSEQ                 LWIP_TCP
1304 #endif
1305 
1306 /**
1307  * LWIP_TCP_SACK_OUT==1: TCP will support sending selective acknowledgements (SACKs).
1308  */
1309 #if !defined LWIP_TCP_SACK_OUT || defined __DOXYGEN__
1310 #define LWIP_TCP_SACK_OUT               0
1311 #endif
1312 
1313 /**
1314  * LWIP_TCP_MAX_SACK_NUM: The maximum number of SACK values to include in TCP segments.
1315  * Must be at least 1, but is only used if LWIP_TCP_SACK_OUT is enabled.
1316  * NOTE: Even though we never send more than 3 or 4 SACK ranges in a single segment
1317  * (depending on other options), setting this option to values greater than 4 is not pointless.
1318  * This is basically the max number of SACK ranges we want to keep track of.
1319  * As new data is delivered, some of the SACK ranges may be removed or merged.
1320  * In that case some of those older SACK ranges may be used again.
1321  * The amount of memory used to store SACK ranges is LWIP_TCP_MAX_SACK_NUM * 8 bytes for each TCP PCB.
1322  */
1323 #if !defined LWIP_TCP_MAX_SACK_NUM || defined __DOXYGEN__
1324 #define LWIP_TCP_MAX_SACK_NUM           4
1325 #endif
1326 
1327 /**
1328  * TCP_MSS: TCP Maximum segment size. (default is 536, a conservative default,
1329  * you might want to increase this.)
1330  * For the receive side, this MSS is advertised to the remote side
1331  * when opening a connection. For the transmit size, this MSS sets
1332  * an upper limit on the MSS advertised by the remote host.
1333  */
1334 #if !defined TCP_MSS || defined __DOXYGEN__
1335 #define TCP_MSS                         536
1336 #endif
1337 
1338 /**
1339  * TCP_CALCULATE_EFF_SEND_MSS: "The maximum size of a segment that TCP really
1340  * sends, the 'effective send MSS,' MUST be the smaller of the send MSS (which
1341  * reflects the available reassembly buffer size at the remote host) and the
1342  * largest size permitted by the IP layer" (RFC 1122)
1343  * Setting this to 1 enables code that checks TCP_MSS against the MTU of the
1344  * netif used for a connection and limits the MSS if it would be too big otherwise.
1345  */
1346 #if !defined TCP_CALCULATE_EFF_SEND_MSS || defined __DOXYGEN__
1347 #define TCP_CALCULATE_EFF_SEND_MSS      1
1348 #endif
1349 
1350 /**
1351  * LWIP_TCP_RTO_TIME: Initial TCP retransmission timeout (ms).
1352  * This defaults to 3 seconds as traditionally defined in the TCP protocol.
1353  * For improving timely recovery on faster networks, this value could
1354  * be lowered down to 1 second (RFC 6298)
1355  */
1356 #if !defined LWIP_TCP_RTO_TIME || defined __DOXYGEN__
1357 #define LWIP_TCP_RTO_TIME               3000
1358 #endif
1359 
1360 /**
1361  * TCP_SND_BUF: TCP sender buffer space (bytes).
1362  * To achieve good performance, this should be at least 2 * TCP_MSS.
1363  */
1364 #if !defined TCP_SND_BUF || defined __DOXYGEN__
1365 #define TCP_SND_BUF                     (2 * TCP_MSS)
1366 #endif
1367 
1368 /**
1369  * TCP_SND_QUEUELEN: TCP sender buffer space (pbufs). This must be at least
1370  * as much as (2 * TCP_SND_BUF/TCP_MSS) for things to work.
1371  */
1372 #if !defined TCP_SND_QUEUELEN || defined __DOXYGEN__
1373 #define TCP_SND_QUEUELEN                ((4 * (TCP_SND_BUF) + (TCP_MSS - 1))/(TCP_MSS))
1374 #endif
1375 
1376 /**
1377  * TCP_SNDLOWAT: TCP writable space (bytes). This must be less than
1378  * TCP_SND_BUF. It is the amount of space which must be available in the
1379  * TCP snd_buf for select to return writable (combined with TCP_SNDQUEUELOWAT).
1380  */
1381 #if !defined TCP_SNDLOWAT || defined __DOXYGEN__
1382 #define TCP_SNDLOWAT                    LWIP_MIN(LWIP_MAX(((TCP_SND_BUF)/2), (2 * TCP_MSS) + 1), (TCP_SND_BUF) - 1)
1383 #endif
1384 
1385 /**
1386  * TCP_SNDQUEUELOWAT: TCP writable bufs (pbuf count). This must be less
1387  * than TCP_SND_QUEUELEN. If the number of pbufs queued on a pcb drops below
1388  * this number, select returns writable (combined with TCP_SNDLOWAT).
1389  */
1390 #if !defined TCP_SNDQUEUELOWAT || defined __DOXYGEN__
1391 #define TCP_SNDQUEUELOWAT               LWIP_MAX(((TCP_SND_QUEUELEN)/2), 5)
1392 #endif
1393 
1394 /**
1395  * TCP_OOSEQ_MAX_BYTES: The default maximum number of bytes queued on ooseq per
1396  * pcb if TCP_OOSEQ_BYTES_LIMIT is not defined. Default is 0 (no limit).
1397  * Only valid for TCP_QUEUE_OOSEQ==1.
1398  */
1399 #if !defined TCP_OOSEQ_MAX_BYTES || defined __DOXYGEN__
1400 #define TCP_OOSEQ_MAX_BYTES             0
1401 #endif
1402 
1403 /**
1404  * TCP_OOSEQ_BYTES_LIMIT(pcb): Return the maximum number of bytes to be queued
1405  * on ooseq per pcb, given the pcb. Only valid for TCP_QUEUE_OOSEQ==1 &&
1406  * TCP_OOSEQ_MAX_BYTES==1.
1407  * Use this to override TCP_OOSEQ_MAX_BYTES to a dynamic value per pcb.
1408  */
1409 #if !defined TCP_OOSEQ_BYTES_LIMIT
1410 #if TCP_OOSEQ_MAX_BYTES
1411 #define TCP_OOSEQ_BYTES_LIMIT(pcb)      TCP_OOSEQ_MAX_BYTES
1412 #elif defined __DOXYGEN__
1413 #define TCP_OOSEQ_BYTES_LIMIT(pcb)
1414 #endif
1415 #endif
1416 
1417 /**
1418  * TCP_OOSEQ_MAX_PBUFS: The default maximum number of pbufs queued on ooseq per
1419  * pcb if TCP_OOSEQ_BYTES_LIMIT is not defined. Default is 0 (no limit).
1420  * Only valid for TCP_QUEUE_OOSEQ==1.
1421  */
1422 #if !defined TCP_OOSEQ_MAX_PBUFS || defined __DOXYGEN__
1423 #define TCP_OOSEQ_MAX_PBUFS             0
1424 #endif
1425 
1426 /**
1427  * TCP_OOSEQ_PBUFS_LIMIT(pcb): Return the maximum number of pbufs to be queued
1428  * on ooseq per pcb, given the pcb.  Only valid for TCP_QUEUE_OOSEQ==1 &&
1429  * TCP_OOSEQ_MAX_PBUFS==1.
1430  * Use this to override TCP_OOSEQ_MAX_PBUFS to a dynamic value per pcb.
1431  */
1432 #if !defined TCP_OOSEQ_PBUFS_LIMIT
1433 #if TCP_OOSEQ_MAX_PBUFS
1434 #define TCP_OOSEQ_PBUFS_LIMIT(pcb)      TCP_OOSEQ_MAX_PBUFS
1435 #elif defined __DOXYGEN__
1436 #define TCP_OOSEQ_PBUFS_LIMIT(pcb)
1437 #endif
1438 #endif
1439 
1440 /**
1441  * TCP_LISTEN_BACKLOG: Enable the backlog option for tcp listen pcb.
1442  */
1443 #if !defined TCP_LISTEN_BACKLOG || defined __DOXYGEN__
1444 #define TCP_LISTEN_BACKLOG              0
1445 #endif
1446 
1447 /**
1448  * The maximum allowed backlog for TCP listen netconns.
1449  * This backlog is used unless another is explicitly specified.
1450  * 0xff is the maximum (u8_t).
1451  */
1452 #if !defined TCP_DEFAULT_LISTEN_BACKLOG || defined __DOXYGEN__
1453 #define TCP_DEFAULT_LISTEN_BACKLOG      0xff
1454 #endif
1455 
1456 /**
1457  * TCP_OVERSIZE: The maximum number of bytes that tcp_write may
1458  * allocate ahead of time in an attempt to create shorter pbuf chains
1459  * for transmission. The meaningful range is 0 to TCP_MSS. Some
1460  * suggested values are:
1461  *
1462  * 0:         Disable oversized allocation. Each tcp_write() allocates a new
1463               pbuf (old behaviour).
1464  * 1:         Allocate size-aligned pbufs with minimal excess. Use this if your
1465  *            scatter-gather DMA requires aligned fragments.
1466  * 128:       Limit the pbuf/memory overhead to 20%.
1467  * TCP_MSS:   Try to create unfragmented TCP packets.
1468  * TCP_MSS/4: Try to create 4 fragments or less per TCP packet.
1469  */
1470 #if !defined TCP_OVERSIZE || defined __DOXYGEN__
1471 #define TCP_OVERSIZE                    TCP_MSS
1472 #endif
1473 
1474 /**
1475  * LWIP_TCP_TIMESTAMPS==1: support the TCP timestamp option.
1476  * The timestamp option is currently only used to help remote hosts, it is not
1477  * really used locally. Therefore, it is only enabled when a TS option is
1478  * received in the initial SYN packet from a remote host.
1479  */
1480 #if !defined LWIP_TCP_TIMESTAMPS || defined __DOXYGEN__
1481 #define LWIP_TCP_TIMESTAMPS             0
1482 #endif
1483 
1484 /**
1485  * TCP_WND_UPDATE_THRESHOLD: difference in window to trigger an
1486  * explicit window update
1487  */
1488 #if !defined TCP_WND_UPDATE_THRESHOLD || defined __DOXYGEN__
1489 #define TCP_WND_UPDATE_THRESHOLD        LWIP_MIN((TCP_WND / 4), (TCP_MSS * 4))
1490 #endif
1491 
1492 /**
1493  * LWIP_EVENT_API and LWIP_CALLBACK_API: Only one of these should be set to 1.
1494  *     LWIP_EVENT_API==1: The user defines lwip_tcp_event() to receive all
1495  *         events (accept, sent, etc) that happen in the system.
1496  *     LWIP_CALLBACK_API==1: The PCB callback function is called directly
1497  *         for the event. This is the default.
1498  */
1499 #if !defined(LWIP_EVENT_API) && !defined(LWIP_CALLBACK_API) || defined __DOXYGEN__
1500 #define LWIP_EVENT_API                  0
1501 #define LWIP_CALLBACK_API               1
1502 #else
1503 #ifndef LWIP_EVENT_API
1504 #define LWIP_EVENT_API                  0
1505 #endif
1506 #ifndef LWIP_CALLBACK_API
1507 #define LWIP_CALLBACK_API               0
1508 #endif
1509 #endif
1510 
1511 /**
1512  * LWIP_WND_SCALE and TCP_RCV_SCALE:
1513  * Set LWIP_WND_SCALE to 1 to enable window scaling.
1514  * Set TCP_RCV_SCALE to the desired scaling factor (shift count in the
1515  * range of [0..14]).
1516  * When LWIP_WND_SCALE is enabled but TCP_RCV_SCALE is 0, we can use a large
1517  * send window while having a small receive window only.
1518  */
1519 #if !defined LWIP_WND_SCALE || defined __DOXYGEN__
1520 #define LWIP_WND_SCALE                  0
1521 #define TCP_RCV_SCALE                   0
1522 #endif
1523 
1524 /**
1525  * LWIP_TCP_PCB_NUM_EXT_ARGS:
1526  * When this is > 0, every tcp pcb (including listen pcb) includes a number of
1527  * additional argument entries in an array (see tcp_ext_arg_alloc_id)
1528  */
1529 #if !defined LWIP_TCP_PCB_NUM_EXT_ARGS || defined __DOXYGEN__
1530 #define LWIP_TCP_PCB_NUM_EXT_ARGS       0
1531 #endif
1532 
1533 /** LWIP_ALTCP==1: enable the altcp API.
1534  * altcp is an abstraction layer that prevents applications linking against the
1535  * tcp.h functions but provides the same functionality. It is used to e.g. add
1536  * SSL/TLS or proxy-connect support to an application written for the tcp callback
1537  * API without that application knowing the protocol details.
1538  *
1539  * With LWIP_ALTCP==0, applications written against the altcp API can still be
1540  * compiled but are directly linked against the tcp.h callback API and then
1541  * cannot use layered protocols.
1542  *
1543  * See @ref altcp_api
1544  */
1545 #if !defined LWIP_ALTCP || defined __DOXYGEN__
1546 #define LWIP_ALTCP                      0
1547 #endif
1548 
1549 /** LWIP_ALTCP_TLS==1: enable TLS support for altcp API.
1550  * This needs a port of the functions in altcp_tls.h to a TLS library.
1551  * A port to ARM mbedtls is provided with lwIP, see apps/altcp_tls/ directory
1552  * and LWIP_ALTCP_TLS_MBEDTLS option.
1553  */
1554 #if !defined LWIP_ALTCP_TLS || defined __DOXYGEN__
1555 #define LWIP_ALTCP_TLS                  0
1556 #endif
1557 
1558 /**
1559  * @}
1560  */
1561 
1562 /*
1563    ----------------------------------
1564    ---------- Pbuf options ----------
1565    ----------------------------------
1566 */
1567 /**
1568  * @defgroup lwip_opts_pbuf PBUF
1569  * @ingroup lwip_opts
1570  * @{
1571  */
1572 /**
1573  * PBUF_LINK_HLEN: the number of bytes that should be allocated for a
1574  * link level header. The default is 14, the standard value for
1575  * Ethernet.
1576  */
1577  #if !defined PBUF_LINK_HLEN || defined __DOXYGEN__
1578 #if (defined LWIP_HOOK_VLAN_SET || LWIP_VLAN_PCP) && !defined __DOXYGEN__
1579  #define PBUF_LINK_HLEN                  (18 + ETH_PAD_SIZE)
1580 #else /* LWIP_HOOK_VLAN_SET || LWIP_VLAN_PCP */
1581  #define PBUF_LINK_HLEN                  (14 + ETH_PAD_SIZE)
1582 #endif /* LWIP_HOOK_VLAN_SET || LWIP_VLAN_PCP */
1583  #endif
1584 
1585 /**
1586  * PBUF_LINK_ENCAPSULATION_HLEN: the number of bytes that should be allocated
1587  * for an additional encapsulation header before ethernet headers (e.g. 802.11)
1588  */
1589 #if !defined PBUF_LINK_ENCAPSULATION_HLEN || defined __DOXYGEN__
1590 #define PBUF_LINK_ENCAPSULATION_HLEN    0
1591 #endif
1592 
1593 /**
1594  * PBUF_POOL_BUFSIZE: the size of each pbuf in the pbuf pool. The default is
1595  * designed to accommodate single full size TCP frame in one pbuf, including
1596  * TCP_MSS, IP header, and link header.
1597  */
1598 #if !defined PBUF_POOL_BUFSIZE || defined __DOXYGEN__
1599 #define PBUF_POOL_BUFSIZE               LWIP_MEM_ALIGN_SIZE(TCP_MSS+PBUF_IP_HLEN+PBUF_TRANSPORT_HLEN+PBUF_LINK_ENCAPSULATION_HLEN+PBUF_LINK_HLEN)
1600 #endif
1601 
1602 /**
1603  * LWIP_PBUF_REF_T: Refcount type in pbuf.
1604  * Default width of u8_t can be increased if 255 refs are not enough for you.
1605  */
1606 #if !defined LWIP_PBUF_REF_T || defined __DOXYGEN__
1607 #define LWIP_PBUF_REF_T                 u8_t
1608 #endif
1609 
1610 /**
1611  * LWIP_PBUF_CUSTOM_DATA: Store private data on pbufs (e.g. timestamps)
1612  * This extends struct pbuf so user can store custom data on every pbuf.
1613  */
1614 #if !defined LWIP_PBUF_CUSTOM_DATA || defined __DOXYGEN__
1615 #define LWIP_PBUF_CUSTOM_DATA
1616 #endif
1617 /**
1618  * @}
1619  */
1620 
1621 /*
1622    ------------------------------------------------
1623    ---------- Network Interfaces options ----------
1624    ------------------------------------------------
1625 */
1626 /**
1627  * @defgroup lwip_opts_netif NETIF
1628  * @ingroup lwip_opts
1629  * @{
1630  */
1631 /**
1632  * LWIP_SINGLE_NETIF==1: use a single netif only. This is the common case for
1633  * small real-life targets. Some code like routing etc. can be left out.
1634  */
1635 #if !defined LWIP_SINGLE_NETIF || defined __DOXYGEN__
1636 #define LWIP_SINGLE_NETIF               0
1637 #endif
1638 
1639 /**
1640  * LWIP_NETIF_HOSTNAME==1: use DHCP_OPTION_HOSTNAME with netif's hostname
1641  * field.
1642  */
1643 #if !defined LWIP_NETIF_HOSTNAME || defined __DOXYGEN__
1644 #define LWIP_NETIF_HOSTNAME             0
1645 #endif
1646 
1647 /**
1648  * LWIP_NETIF_API==1: Support netif api (in netifapi.c)
1649  */
1650 #if !defined LWIP_NETIF_API || defined __DOXYGEN__
1651 #define LWIP_NETIF_API                  0
1652 #endif
1653 
1654 /**
1655  * LWIP_NETIF_STATUS_CALLBACK==1: Support a callback function whenever an interface
1656  * changes its up/down status (i.e., due to DHCP IP acquisition)
1657  */
1658 #if !defined LWIP_NETIF_STATUS_CALLBACK || defined __DOXYGEN__
1659 #define LWIP_NETIF_STATUS_CALLBACK      0
1660 #endif
1661 
1662 /**
1663  * LWIP_NETIF_EXT_STATUS_CALLBACK==1: Support an extended callback function
1664  * for several netif related event that supports multiple subscribers.
1665  * @see netif_ext_status_callback
1666  */
1667 #if !defined LWIP_NETIF_EXT_STATUS_CALLBACK || defined __DOXYGEN__
1668 #define LWIP_NETIF_EXT_STATUS_CALLBACK  0
1669 #endif
1670 
1671 /**
1672  * LWIP_NETIF_LINK_CALLBACK==1: Support a callback function from an interface
1673  * whenever the link changes (i.e., link down)
1674  */
1675 #if !defined LWIP_NETIF_LINK_CALLBACK || defined __DOXYGEN__
1676 #define LWIP_NETIF_LINK_CALLBACK        0
1677 #endif
1678 
1679 /**
1680  * LWIP_NETIF_REMOVE_CALLBACK==1: Support a callback function that is called
1681  * when a netif has been removed
1682  */
1683 #if !defined LWIP_NETIF_REMOVE_CALLBACK || defined __DOXYGEN__
1684 #define LWIP_NETIF_REMOVE_CALLBACK      0
1685 #endif
1686 
1687 /**
1688  * LWIP_NETIF_HWADDRHINT==1: Cache link-layer-address hints (e.g. table
1689  * indices) in struct netif. TCP and UDP can make use of this to prevent
1690  * scanning the ARP table for every sent packet. While this is faster for big
1691  * ARP tables or many concurrent connections, it might be counterproductive
1692  * if you have a tiny ARP table or if there never are concurrent connections.
1693  */
1694 #if !defined LWIP_NETIF_HWADDRHINT || defined __DOXYGEN__
1695 #define LWIP_NETIF_HWADDRHINT           0
1696 #endif
1697 
1698 /**
1699  * LWIP_NETIF_TX_SINGLE_PBUF: if this is set to 1, lwIP *tries* to put all data
1700  * to be sent into one single pbuf. This is for compatibility with DMA-enabled
1701  * MACs that do not support scatter-gather.
1702  * Beware that this might involve CPU-memcpy before transmitting that would not
1703  * be needed without this flag! Use this only if you need to!
1704  *
1705  * ATTENTION: a driver should *NOT* rely on getting single pbufs but check TX
1706  * pbufs for being in one piece. If not, @ref pbuf_clone can be used to get
1707  * a single pbuf:
1708  *   if (p->next != NULL) {
1709  *     struct pbuf *q = pbuf_clone(PBUF_RAW, PBUF_RAM, p);
1710  *     if (q == NULL) {
1711  *       return ERR_MEM;
1712  *     }
1713  *     p = q; ATTENTION: do NOT free the old 'p' as the ref belongs to the caller!
1714  *   }
1715  */
1716 #if !defined LWIP_NETIF_TX_SINGLE_PBUF || defined __DOXYGEN__
1717 #define LWIP_NETIF_TX_SINGLE_PBUF       0
1718 #endif /* LWIP_NETIF_TX_SINGLE_PBUF */
1719 
1720 /**
1721  * LWIP_NUM_NETIF_CLIENT_DATA: Number of clients that may store
1722  * data in client_data member array of struct netif (max. 256).
1723  */
1724 #if !defined LWIP_NUM_NETIF_CLIENT_DATA || defined __DOXYGEN__
1725 #define LWIP_NUM_NETIF_CLIENT_DATA      0
1726 #endif
1727 /**
1728  * @}
1729  */
1730 
1731 /*
1732    ------------------------------------
1733    ---------- LOOPIF options ----------
1734    ------------------------------------
1735 */
1736 /**
1737  * @defgroup lwip_opts_loop Loopback interface
1738  * @ingroup lwip_opts_netif
1739  * @{
1740  */
1741 /**
1742  * LWIP_HAVE_LOOPIF==1: Support loop interface (127.0.0.1).
1743  * This is only needed when no real netifs are available. If at least one other
1744  * netif is available, loopback traffic uses this netif.
1745  */
1746 #if !defined LWIP_HAVE_LOOPIF || defined __DOXYGEN__
1747 #define LWIP_HAVE_LOOPIF                (LWIP_NETIF_LOOPBACK && !LWIP_SINGLE_NETIF)
1748 #endif
1749 
1750 /**
1751  * LWIP_LOOPIF_MULTICAST==1: Support multicast/IGMP on loop interface (127.0.0.1).
1752  */
1753 #if !defined LWIP_LOOPIF_MULTICAST || defined __DOXYGEN__
1754 #define LWIP_LOOPIF_MULTICAST           0
1755 #endif
1756 
1757 /**
1758  * LWIP_NETIF_LOOPBACK==1: Support sending packets with a destination IP
1759  * address equal to the netif IP address, looping them back up the stack.
1760  */
1761 #if !defined LWIP_NETIF_LOOPBACK || defined __DOXYGEN__
1762 #define LWIP_NETIF_LOOPBACK             0
1763 #endif
1764 
1765 /**
1766  * LWIP_LOOPBACK_MAX_PBUFS: Maximum number of pbufs on queue for loopback
1767  * sending for each netif (0 = disabled)
1768  */
1769 #if !defined LWIP_LOOPBACK_MAX_PBUFS || defined __DOXYGEN__
1770 #define LWIP_LOOPBACK_MAX_PBUFS         0
1771 #endif
1772 
1773 /**
1774  * LWIP_NETIF_LOOPBACK_MULTITHREADING: Indicates whether threading is enabled in
1775  * the system, as netifs must change how they behave depending on this setting
1776  * for the LWIP_NETIF_LOOPBACK option to work.
1777  * Setting this is needed to avoid reentering non-reentrant functions like
1778  * tcp_input().
1779  *    LWIP_NETIF_LOOPBACK_MULTITHREADING==1: Indicates that the user is using a
1780  *       multithreaded environment like tcpip.c. In this case, netif->input()
1781  *       is called directly.
1782  *    LWIP_NETIF_LOOPBACK_MULTITHREADING==0: Indicates a polling (or NO_SYS) setup.
1783  *       The packets are put on a list and netif_poll() must be called in
1784  *       the main application loop.
1785  */
1786 #if !defined LWIP_NETIF_LOOPBACK_MULTITHREADING || defined __DOXYGEN__
1787 #define LWIP_NETIF_LOOPBACK_MULTITHREADING    (!NO_SYS)
1788 #endif
1789 /**
1790  * @}
1791  */
1792 
1793 /*
1794    ------------------------------------
1795    ---------- Thread options ----------
1796    ------------------------------------
1797 */
1798 /**
1799  * @defgroup lwip_opts_thread Threading
1800  * @ingroup lwip_opts_infrastructure
1801  * @{
1802  */
1803 /**
1804  * TCPIP_THREAD_NAME: The name assigned to the main tcpip thread.
1805  */
1806 #if !defined TCPIP_THREAD_NAME || defined __DOXYGEN__
1807 #define TCPIP_THREAD_NAME               "tcpip_thread"
1808 #endif
1809 
1810 /**
1811  * TCPIP_THREAD_STACKSIZE: The stack size used by the main tcpip thread.
1812  * The stack size value itself is platform-dependent, but is passed to
1813  * sys_thread_new() when the thread is created.
1814  */
1815 #if !defined TCPIP_THREAD_STACKSIZE || defined __DOXYGEN__
1816 #define TCPIP_THREAD_STACKSIZE          0
1817 #endif
1818 
1819 /**
1820  * TCPIP_THREAD_PRIO: The priority assigned to the main tcpip thread.
1821  * The priority value itself is platform-dependent, but is passed to
1822  * sys_thread_new() when the thread is created.
1823  */
1824 #if !defined TCPIP_THREAD_PRIO || defined __DOXYGEN__
1825 #define TCPIP_THREAD_PRIO               1
1826 #endif
1827 
1828 /**
1829  * TCPIP_MBOX_SIZE: The mailbox size for the tcpip thread messages
1830  * The queue size value itself is platform-dependent, but is passed to
1831  * sys_mbox_new() when tcpip_init is called.
1832  */
1833 #if !defined TCPIP_MBOX_SIZE || defined __DOXYGEN__
1834 #define TCPIP_MBOX_SIZE                 0
1835 #endif
1836 
1837 /**
1838  * Define this to something that triggers a watchdog. This is called from
1839  * tcpip_thread after processing a message.
1840  */
1841 #if !defined LWIP_TCPIP_THREAD_ALIVE || defined __DOXYGEN__
1842 #define LWIP_TCPIP_THREAD_ALIVE()
1843 #endif
1844 
1845 /**
1846  * SLIPIF_THREAD_NAME: The name assigned to the slipif_loop thread.
1847  */
1848 #if !defined SLIPIF_THREAD_NAME || defined __DOXYGEN__
1849 #define SLIPIF_THREAD_NAME              "slipif_loop"
1850 #endif
1851 
1852 /**
1853  * SLIP_THREAD_STACKSIZE: The stack size used by the slipif_loop thread.
1854  * The stack size value itself is platform-dependent, but is passed to
1855  * sys_thread_new() when the thread is created.
1856  */
1857 #if !defined SLIPIF_THREAD_STACKSIZE || defined __DOXYGEN__
1858 #define SLIPIF_THREAD_STACKSIZE         0
1859 #endif
1860 
1861 /**
1862  * SLIPIF_THREAD_PRIO: The priority assigned to the slipif_loop thread.
1863  * The priority value itself is platform-dependent, but is passed to
1864  * sys_thread_new() when the thread is created.
1865  */
1866 #if !defined SLIPIF_THREAD_PRIO || defined __DOXYGEN__
1867 #define SLIPIF_THREAD_PRIO              1
1868 #endif
1869 
1870 /**
1871  * DEFAULT_THREAD_NAME: The name assigned to any other lwIP thread.
1872  */
1873 #if !defined DEFAULT_THREAD_NAME || defined __DOXYGEN__
1874 #define DEFAULT_THREAD_NAME             "lwIP"
1875 #endif
1876 
1877 /**
1878  * DEFAULT_THREAD_STACKSIZE: The stack size used by any other lwIP thread.
1879  * The stack size value itself is platform-dependent, but is passed to
1880  * sys_thread_new() when the thread is created.
1881  */
1882 #if !defined DEFAULT_THREAD_STACKSIZE || defined __DOXYGEN__
1883 #define DEFAULT_THREAD_STACKSIZE        0
1884 #endif
1885 
1886 /**
1887  * DEFAULT_THREAD_PRIO: The priority assigned to any other lwIP thread.
1888  * The priority value itself is platform-dependent, but is passed to
1889  * sys_thread_new() when the thread is created.
1890  */
1891 #if !defined DEFAULT_THREAD_PRIO || defined __DOXYGEN__
1892 #define DEFAULT_THREAD_PRIO             1
1893 #endif
1894 
1895 /**
1896  * DEFAULT_RAW_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
1897  * NETCONN_RAW. The queue size value itself is platform-dependent, but is passed
1898  * to sys_mbox_new() when the recvmbox is created.
1899  */
1900 #if !defined DEFAULT_RAW_RECVMBOX_SIZE || defined __DOXYGEN__
1901 #define DEFAULT_RAW_RECVMBOX_SIZE       0
1902 #endif
1903 
1904 /**
1905  * DEFAULT_UDP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
1906  * NETCONN_UDP. The queue size value itself is platform-dependent, but is passed
1907  * to sys_mbox_new() when the recvmbox is created.
1908  */
1909 #if !defined DEFAULT_UDP_RECVMBOX_SIZE || defined __DOXYGEN__
1910 #define DEFAULT_UDP_RECVMBOX_SIZE       0
1911 #endif
1912 
1913 /**
1914  * DEFAULT_TCP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
1915  * NETCONN_TCP. The queue size value itself is platform-dependent, but is passed
1916  * to sys_mbox_new() when the recvmbox is created.
1917  */
1918 #if !defined DEFAULT_TCP_RECVMBOX_SIZE || defined __DOXYGEN__
1919 #define DEFAULT_TCP_RECVMBOX_SIZE       0
1920 #endif
1921 
1922 /**
1923  * DEFAULT_ACCEPTMBOX_SIZE: The mailbox size for the incoming connections.
1924  * The queue size value itself is platform-dependent, but is passed to
1925  * sys_mbox_new() when the acceptmbox is created.
1926  */
1927 #if !defined DEFAULT_ACCEPTMBOX_SIZE || defined __DOXYGEN__
1928 #define DEFAULT_ACCEPTMBOX_SIZE         0
1929 #endif
1930 /**
1931  * @}
1932  */
1933 
1934 /*
1935    ----------------------------------------------
1936    ---------- Sequential layer options ----------
1937    ----------------------------------------------
1938 */
1939 /**
1940  * @defgroup lwip_opts_netconn Netconn
1941  * @ingroup lwip_opts_threadsafe_apis
1942  * @{
1943  */
1944 /**
1945  * LWIP_NETCONN==1: Enable Netconn API (require to use api_lib.c)
1946  */
1947 #if !defined LWIP_NETCONN || defined __DOXYGEN__
1948 #define LWIP_NETCONN                    1
1949 #endif
1950 
1951 /** LWIP_TCPIP_TIMEOUT==1: Enable tcpip_timeout/tcpip_untimeout to create
1952  * timers running in tcpip_thread from another thread.
1953  */
1954 #if !defined LWIP_TCPIP_TIMEOUT || defined __DOXYGEN__
1955 #define LWIP_TCPIP_TIMEOUT              0
1956 #endif
1957 
1958 /** LWIP_NETCONN_SEM_PER_THREAD==1: Use one (thread-local) semaphore per
1959  * thread calling socket/netconn functions instead of allocating one
1960  * semaphore per netconn (and per select etc.)
1961  * ATTENTION: a thread-local semaphore for API calls is needed:
1962  * - LWIP_NETCONN_THREAD_SEM_GET() returning a sys_sem_t*
1963  * - LWIP_NETCONN_THREAD_SEM_ALLOC() creating the semaphore
1964  * - LWIP_NETCONN_THREAD_SEM_FREE() freeing the semaphore
1965  * The latter 2 can be invoked up by calling netconn_thread_init()/netconn_thread_cleanup().
1966  * Ports may call these for threads created with sys_thread_new().
1967  */
1968 #if !defined LWIP_NETCONN_SEM_PER_THREAD || defined __DOXYGEN__
1969 #define LWIP_NETCONN_SEM_PER_THREAD     0
1970 #endif
1971 
1972 /** LWIP_NETCONN_FULLDUPLEX==1: Enable code that allows reading from one thread,
1973  * writing from a 2nd thread and closing from a 3rd thread at the same time.
1974  * LWIP_NETCONN_SEM_PER_THREAD==1 is required to use one socket/netconn from
1975  * multiple threads at once!
1976  */
1977 #if !defined LWIP_NETCONN_FULLDUPLEX || defined __DOXYGEN__
1978 #define LWIP_NETCONN_FULLDUPLEX         0
1979 #endif
1980 /**
1981  * @}
1982  */
1983 
1984 /*
1985    ------------------------------------
1986    ---------- Socket options ----------
1987    ------------------------------------
1988 */
1989 /**
1990  * @defgroup lwip_opts_socket Sockets
1991  * @ingroup lwip_opts_threadsafe_apis
1992  * @{
1993  */
1994 /**
1995  * LWIP_SOCKET==1: Enable Socket API (require to use sockets.c)
1996  */
1997 #if !defined LWIP_SOCKET || defined __DOXYGEN__
1998 #define LWIP_SOCKET                     1
1999 #endif
2000 
2001 /**
2002  * LWIP_COMPAT_SOCKETS==1: Enable BSD-style sockets functions names through defines.
2003  * LWIP_COMPAT_SOCKETS==2: Same as ==1 but correctly named functions are created.
2004  * While this helps code completion, it might conflict with existing libraries.
2005  * (only used if you use sockets.c)
2006  */
2007 #if !defined LWIP_COMPAT_SOCKETS || defined __DOXYGEN__
2008 #define LWIP_COMPAT_SOCKETS             1
2009 #endif
2010 
2011 /**
2012  * LWIP_POSIX_SOCKETS_IO_NAMES==1: Enable POSIX-style sockets functions names.
2013  * Disable this option if you use a POSIX operating system that uses the same
2014  * names (read, write & close). (only used if you use sockets.c)
2015  */
2016 #if !defined LWIP_POSIX_SOCKETS_IO_NAMES || defined __DOXYGEN__
2017 #define LWIP_POSIX_SOCKETS_IO_NAMES     1
2018 #endif
2019 
2020 /**
2021  * LWIP_SOCKET_OFFSET==n: Increases the file descriptor number created by LwIP with n.
2022  * This can be useful when there are multiple APIs which create file descriptors.
2023  * When they all start with a different offset and you won't make them overlap you can
2024  * re implement read/write/close/ioctl/fnctl to send the requested action to the right
2025  * library (sharing select will need more work though).
2026  */
2027 #if !defined LWIP_SOCKET_OFFSET || defined __DOXYGEN__
2028 #define LWIP_SOCKET_OFFSET              0
2029 #endif
2030 
2031 /**
2032  * LWIP_SOCKET_EXTERNAL_HEADERS==1: Use external headers instead of sockets.h
2033  * and inet.h. In this case, user must provide its own headers by setting the
2034  * values for LWIP_SOCKET_EXTERNAL_HEADER_SOCKETS_H and
2035  * LWIP_SOCKET_EXTERNAL_HEADER_INET_H to appropriate include file names and the
2036  * whole content of the default sockets.h and inet.h is skipped.
2037  */
2038 #if !defined LWIP_SOCKET_EXTERNAL_HEADERS || defined __DOXYGEN__
2039 #define LWIP_SOCKET_EXTERNAL_HEADERS    0
2040 #endif
2041 
2042 /**
2043  * LWIP_TCP_KEEPALIVE==1: Enable TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT
2044  * options processing. Note that TCP_KEEPIDLE and TCP_KEEPINTVL have to be set
2045  * in seconds. (does not require sockets.c, and will affect tcp.c)
2046  */
2047 #if !defined LWIP_TCP_KEEPALIVE || defined __DOXYGEN__
2048 #define LWIP_TCP_KEEPALIVE              0
2049 #endif
2050 
2051 /**
2052  * LWIP_SO_SNDTIMEO==1: Enable send timeout for sockets/netconns and
2053  * SO_SNDTIMEO processing.
2054  */
2055 #if !defined LWIP_SO_SNDTIMEO || defined __DOXYGEN__
2056 #define LWIP_SO_SNDTIMEO                0
2057 #endif
2058 
2059 /**
2060  * LWIP_SO_RCVTIMEO==1: Enable receive timeout for sockets/netconns and
2061  * SO_RCVTIMEO processing.
2062  */
2063 #if !defined LWIP_SO_RCVTIMEO || defined __DOXYGEN__
2064 #define LWIP_SO_RCVTIMEO                0
2065 #endif
2066 
2067 /**
2068  * LWIP_SO_SNDRCVTIMEO_NONSTANDARD==1: SO_RCVTIMEO/SO_SNDTIMEO take an int
2069  * (milliseconds, much like winsock does) instead of a struct timeval (default).
2070  */
2071 #if !defined LWIP_SO_SNDRCVTIMEO_NONSTANDARD || defined __DOXYGEN__
2072 #define LWIP_SO_SNDRCVTIMEO_NONSTANDARD 0
2073 #endif
2074 
2075 /**
2076  * LWIP_SO_RCVBUF==1: Enable SO_RCVBUF processing.
2077  */
2078 #if !defined LWIP_SO_RCVBUF || defined __DOXYGEN__
2079 #define LWIP_SO_RCVBUF                  0
2080 #endif
2081 
2082 /**
2083  * LWIP_SO_LINGER==1: Enable SO_LINGER processing.
2084  */
2085 #if !defined LWIP_SO_LINGER || defined __DOXYGEN__
2086 #define LWIP_SO_LINGER                  0
2087 #endif
2088 
2089 /**
2090  * If LWIP_SO_RCVBUF is used, this is the default value for recv_bufsize.
2091  */
2092 #if !defined RECV_BUFSIZE_DEFAULT || defined __DOXYGEN__
2093 #define RECV_BUFSIZE_DEFAULT            INT_MAX
2094 #endif
2095 
2096 /**
2097  * By default, TCP socket/netconn close waits 20 seconds max to send the FIN
2098  */
2099 #if !defined LWIP_TCP_CLOSE_TIMEOUT_MS_DEFAULT || defined __DOXYGEN__
2100 #define LWIP_TCP_CLOSE_TIMEOUT_MS_DEFAULT 20000
2101 #endif
2102 
2103 /**
2104  * SO_REUSE==1: Enable SO_REUSEADDR option.
2105  */
2106 #if !defined SO_REUSE || defined __DOXYGEN__
2107 #define SO_REUSE                        0
2108 #endif
2109 
2110 /**
2111  * SO_REUSE_RXTOALL==1: Pass a copy of incoming broadcast/multicast packets
2112  * to all local matches if SO_REUSEADDR is turned on.
2113  * WARNING: Adds a memcpy for every packet if passing to more than one pcb!
2114  */
2115 #if !defined SO_REUSE_RXTOALL || defined __DOXYGEN__
2116 #define SO_REUSE_RXTOALL                0
2117 #endif
2118 
2119 /**
2120  * LWIP_FIONREAD_LINUXMODE==0 (default): ioctl/FIONREAD returns the amount of
2121  * pending data in the network buffer. This is the way windows does it. It's
2122  * the default for lwIP since it is smaller.
2123  * LWIP_FIONREAD_LINUXMODE==1: ioctl/FIONREAD returns the size of the next
2124  * pending datagram in bytes. This is the way linux does it. This code is only
2125  * here for compatibility.
2126  */
2127 #if !defined LWIP_FIONREAD_LINUXMODE || defined __DOXYGEN__
2128 #define LWIP_FIONREAD_LINUXMODE         0
2129 #endif
2130 
2131 /**
2132  * LWIP_SOCKET_SELECT==1 (default): enable select() for sockets (uses a netconn
2133  * callback to keep track of events).
2134  * This saves RAM (counters per socket) and code (netconn event callback), which
2135  * should improve performance a bit).
2136  */
2137 #if !defined LWIP_SOCKET_SELECT || defined __DOXYGEN__
2138 #define LWIP_SOCKET_SELECT              1
2139 #endif
2140 
2141 /**
2142  * LWIP_SOCKET_POLL==1 (default): enable poll() for sockets (including
2143  * struct pollfd, nfds_t, and constants)
2144  */
2145 #if !defined LWIP_SOCKET_POLL || defined __DOXYGEN__
2146 #define LWIP_SOCKET_POLL                1
2147 #endif
2148 /**
2149  * @}
2150  */
2151 
2152 /*
2153    ----------------------------------------
2154    ---------- Statistics options ----------
2155    ----------------------------------------
2156 */
2157 /**
2158  * @defgroup lwip_opts_stats Statistics
2159  * @ingroup lwip_opts_debug
2160  * @{
2161  */
2162 /**
2163  * LWIP_STATS==1: Enable statistics collection in lwip_stats.
2164  */
2165 #if !defined LWIP_STATS || defined __DOXYGEN__
2166 #define LWIP_STATS                      1
2167 #endif
2168 
2169 #if LWIP_STATS
2170 
2171 /**
2172  * LWIP_STATS_DISPLAY==1: Compile in the statistics output functions.
2173  */
2174 #if !defined LWIP_STATS_DISPLAY || defined __DOXYGEN__
2175 #define LWIP_STATS_DISPLAY              0
2176 #endif
2177 
2178 /**
2179  * LINK_STATS==1: Enable link stats.
2180  */
2181 #if !defined LINK_STATS || defined __DOXYGEN__
2182 #define LINK_STATS                      1
2183 #endif
2184 
2185 /**
2186  * ETHARP_STATS==1: Enable etharp stats.
2187  */
2188 #if !defined ETHARP_STATS || defined __DOXYGEN__
2189 #define ETHARP_STATS                    (LWIP_ARP)
2190 #endif
2191 
2192 /**
2193  * IP_STATS==1: Enable IP stats.
2194  */
2195 #if !defined IP_STATS || defined __DOXYGEN__
2196 #define IP_STATS                        1
2197 #endif
2198 
2199 /**
2200  * IPFRAG_STATS==1: Enable IP fragmentation stats. Default is
2201  * on if using either frag or reass.
2202  */
2203 #if !defined IPFRAG_STATS || defined __DOXYGEN__
2204 #define IPFRAG_STATS                    (IP_REASSEMBLY || IP_FRAG)
2205 #endif
2206 
2207 /**
2208  * ICMP_STATS==1: Enable ICMP stats.
2209  */
2210 #if !defined ICMP_STATS || defined __DOXYGEN__
2211 #define ICMP_STATS                      1
2212 #endif
2213 
2214 /**
2215  * IGMP_STATS==1: Enable IGMP stats.
2216  */
2217 #if !defined IGMP_STATS || defined __DOXYGEN__
2218 #define IGMP_STATS                      (LWIP_IGMP)
2219 #endif
2220 
2221 /**
2222  * UDP_STATS==1: Enable UDP stats. Default is on if
2223  * UDP enabled, otherwise off.
2224  */
2225 #if !defined UDP_STATS || defined __DOXYGEN__
2226 #define UDP_STATS                       (LWIP_UDP)
2227 #endif
2228 
2229 /**
2230  * TCP_STATS==1: Enable TCP stats. Default is on if TCP
2231  * enabled, otherwise off.
2232  */
2233 #if !defined TCP_STATS || defined __DOXYGEN__
2234 #define TCP_STATS                       (LWIP_TCP)
2235 #endif
2236 
2237 /**
2238  * MEM_STATS==1: Enable mem.c stats.
2239  */
2240 #if !defined MEM_STATS || defined __DOXYGEN__
2241 #define MEM_STATS                       ((MEM_LIBC_MALLOC == 0) && (MEM_USE_POOLS == 0))
2242 #endif
2243 
2244 /**
2245  * MEMP_STATS==1: Enable memp.c pool stats.
2246  */
2247 #if !defined MEMP_STATS || defined __DOXYGEN__
2248 #define MEMP_STATS                      (MEMP_MEM_MALLOC == 0)
2249 #endif
2250 
2251 /**
2252  * SYS_STATS==1: Enable system stats (sem and mbox counts, etc).
2253  */
2254 #if !defined SYS_STATS || defined __DOXYGEN__
2255 #define SYS_STATS                       (NO_SYS == 0)
2256 #endif
2257 
2258 /**
2259  * IP6_STATS==1: Enable IPv6 stats.
2260  */
2261 #if !defined IP6_STATS || defined __DOXYGEN__
2262 #define IP6_STATS                       (LWIP_IPV6)
2263 #endif
2264 
2265 /**
2266  * ICMP6_STATS==1: Enable ICMP for IPv6 stats.
2267  */
2268 #if !defined ICMP6_STATS || defined __DOXYGEN__
2269 #define ICMP6_STATS                     (LWIP_IPV6 && LWIP_ICMP6)
2270 #endif
2271 
2272 /**
2273  * IP6_FRAG_STATS==1: Enable IPv6 fragmentation stats.
2274  */
2275 #if !defined IP6_FRAG_STATS || defined __DOXYGEN__
2276 #define IP6_FRAG_STATS                  (LWIP_IPV6 && (LWIP_IPV6_FRAG || LWIP_IPV6_REASS))
2277 #endif
2278 
2279 /**
2280  * MLD6_STATS==1: Enable MLD for IPv6 stats.
2281  */
2282 #if !defined MLD6_STATS || defined __DOXYGEN__
2283 #define MLD6_STATS                      (LWIP_IPV6 && LWIP_IPV6_MLD)
2284 #endif
2285 
2286 /**
2287  * ND6_STATS==1: Enable Neighbor discovery for IPv6 stats.
2288  */
2289 #if !defined ND6_STATS || defined __DOXYGEN__
2290 #define ND6_STATS                       (LWIP_IPV6)
2291 #endif
2292 
2293 /**
2294  * MIB2_STATS==1: Stats for SNMP MIB2.
2295  */
2296 #if !defined MIB2_STATS || defined __DOXYGEN__
2297 #define MIB2_STATS                      0
2298 #endif
2299 
2300 #else
2301 
2302 #define LINK_STATS                      0
2303 #define ETHARP_STATS                    0
2304 #define IP_STATS                        0
2305 #define IPFRAG_STATS                    0
2306 #define ICMP_STATS                      0
2307 #define IGMP_STATS                      0
2308 #define UDP_STATS                       0
2309 #define TCP_STATS                       0
2310 #define MEM_STATS                       0
2311 #define MEMP_STATS                      0
2312 #define SYS_STATS                       0
2313 #define LWIP_STATS_DISPLAY              0
2314 #define IP6_STATS                       0
2315 #define ICMP6_STATS                     0
2316 #define IP6_FRAG_STATS                  0
2317 #define MLD6_STATS                      0
2318 #define ND6_STATS                       0
2319 #define MIB2_STATS                      0
2320 
2321 #endif /* LWIP_STATS */
2322 /**
2323  * @}
2324  */
2325 
2326 /*
2327    --------------------------------------
2328    ---------- Checksum options ----------
2329    --------------------------------------
2330 */
2331 /**
2332  * @defgroup lwip_opts_checksum Checksum
2333  * @ingroup lwip_opts_infrastructure
2334  * @{
2335  */
2336 /**
2337  * LWIP_CHECKSUM_CTRL_PER_NETIF==1: Checksum generation/check can be enabled/disabled
2338  * per netif.
2339  * ATTENTION: if enabled, the CHECKSUM_GEN_* and CHECKSUM_CHECK_* defines must be enabled!
2340  */
2341 #if !defined LWIP_CHECKSUM_CTRL_PER_NETIF || defined __DOXYGEN__
2342 #define LWIP_CHECKSUM_CTRL_PER_NETIF    0
2343 #endif
2344 
2345 /**
2346  * CHECKSUM_GEN_IP==1: Generate checksums in software for outgoing IP packets.
2347  */
2348 #if !defined CHECKSUM_GEN_IP || defined __DOXYGEN__
2349 #define CHECKSUM_GEN_IP                 1
2350 #endif
2351 
2352 /**
2353  * CHECKSUM_GEN_UDP==1: Generate checksums in software for outgoing UDP packets.
2354  */
2355 #if !defined CHECKSUM_GEN_UDP || defined __DOXYGEN__
2356 #define CHECKSUM_GEN_UDP                1
2357 #endif
2358 
2359 /**
2360  * CHECKSUM_GEN_TCP==1: Generate checksums in software for outgoing TCP packets.
2361  */
2362 #if !defined CHECKSUM_GEN_TCP || defined __DOXYGEN__
2363 #define CHECKSUM_GEN_TCP                1
2364 #endif
2365 
2366 /**
2367  * CHECKSUM_GEN_ICMP==1: Generate checksums in software for outgoing ICMP packets.
2368  */
2369 #if !defined CHECKSUM_GEN_ICMP || defined __DOXYGEN__
2370 #define CHECKSUM_GEN_ICMP               1
2371 #endif
2372 
2373 /**
2374  * CHECKSUM_GEN_ICMP6==1: Generate checksums in software for outgoing ICMP6 packets.
2375  */
2376 #if !defined CHECKSUM_GEN_ICMP6 || defined __DOXYGEN__
2377 #define CHECKSUM_GEN_ICMP6              1
2378 #endif
2379 
2380 /**
2381  * CHECKSUM_CHECK_IP==1: Check checksums in software for incoming IP packets.
2382  */
2383 #if !defined CHECKSUM_CHECK_IP || defined __DOXYGEN__
2384 #define CHECKSUM_CHECK_IP               1
2385 #endif
2386 
2387 /**
2388  * CHECKSUM_CHECK_UDP==1: Check checksums in software for incoming UDP packets.
2389  */
2390 #if !defined CHECKSUM_CHECK_UDP || defined __DOXYGEN__
2391 #define CHECKSUM_CHECK_UDP              1
2392 #endif
2393 
2394 /**
2395  * CHECKSUM_CHECK_TCP==1: Check checksums in software for incoming TCP packets.
2396  */
2397 #if !defined CHECKSUM_CHECK_TCP || defined __DOXYGEN__
2398 #define CHECKSUM_CHECK_TCP              1
2399 #endif
2400 
2401 /**
2402  * CHECKSUM_CHECK_ICMP==1: Check checksums in software for incoming ICMP packets.
2403  */
2404 #if !defined CHECKSUM_CHECK_ICMP || defined __DOXYGEN__
2405 #define CHECKSUM_CHECK_ICMP             1
2406 #endif
2407 
2408 /**
2409  * CHECKSUM_CHECK_ICMP6==1: Check checksums in software for incoming ICMPv6 packets
2410  */
2411 #if !defined CHECKSUM_CHECK_ICMP6 || defined __DOXYGEN__
2412 #define CHECKSUM_CHECK_ICMP6            1
2413 #endif
2414 
2415 /**
2416  * LWIP_CHECKSUM_ON_COPY==1: Calculate checksum when copying data from
2417  * application buffers to pbufs.
2418  */
2419 #if !defined LWIP_CHECKSUM_ON_COPY || defined __DOXYGEN__
2420 #define LWIP_CHECKSUM_ON_COPY           0
2421 #endif
2422 /**
2423  * @}
2424  */
2425 
2426 /*
2427    ---------------------------------------
2428    ---------- IPv6 options ---------------
2429    ---------------------------------------
2430 */
2431 /**
2432  * @defgroup lwip_opts_ipv6 IPv6
2433  * @ingroup lwip_opts
2434  * @{
2435  */
2436 /**
2437  * LWIP_IPV6==1: Enable IPv6
2438  */
2439 #if !defined LWIP_IPV6 || defined __DOXYGEN__
2440 #define LWIP_IPV6                       0
2441 #endif
2442 
2443 /**
2444  * IPV6_REASS_MAXAGE: Maximum time (in multiples of IP6_REASS_TMR_INTERVAL - so seconds, normally)
2445  * a fragmented IP packet waits for all fragments to arrive. If not all fragments arrived
2446  * in this time, the whole packet is discarded.
2447  */
2448 #if !defined IPV6_REASS_MAXAGE || defined __DOXYGEN__
2449 #define IPV6_REASS_MAXAGE               60
2450 #endif
2451 
2452 /**
2453  * LWIP_IPV6_SCOPES==1: Enable support for IPv6 address scopes, ensuring that
2454  * e.g. link-local addresses are really treated as link-local. Disable this
2455  * setting only for single-interface configurations.
2456  * All addresses that have a scope according to the default policy (link-local
2457  * unicast addresses, interface-local and link-local multicast addresses) should
2458  * now have a zone set on them before being passed to the core API, although
2459  * lwIP will currently attempt to select a zone on the caller's behalf when
2460  * necessary. Applications that directly assign IPv6 addresses to interfaces
2461  * (which is NOT recommended) must now ensure that link-local addresses carry
2462  * the netif's zone. See the new ip6_zone.h header file for more information and
2463  * relevant macros. For now it is still possible to turn off scopes support
2464  * through the new LWIP_IPV6_SCOPES option. When upgrading an implementation that
2465  * uses the core API directly, it is highly recommended to enable
2466  * LWIP_IPV6_SCOPES_DEBUG at least for a while, to ensure e.g. proper address
2467  * initialization.
2468  */
2469 #if !defined LWIP_IPV6_SCOPES || defined __DOXYGEN__
2470 #define LWIP_IPV6_SCOPES                (LWIP_IPV6 && !LWIP_SINGLE_NETIF)
2471 #endif
2472 
2473 /**
2474  * LWIP_IPV6_SCOPES_DEBUG==1: Perform run-time checks to verify that addresses
2475  * are properly zoned (see ip6_zone.h on what that means) where it matters.
2476  * Enabling this setting is highly recommended when upgrading from an existing
2477  * installation that is not yet scope-aware; otherwise it may be too expensive.
2478  */
2479 #if !defined LWIP_IPV6_SCOPES_DEBUG || defined __DOXYGEN__
2480 #define LWIP_IPV6_SCOPES_DEBUG          0
2481 #endif
2482 
2483 /**
2484  * LWIP_IPV6_NUM_ADDRESSES: Number of IPv6 addresses per netif.
2485  */
2486 #if !defined LWIP_IPV6_NUM_ADDRESSES || defined __DOXYGEN__
2487 #define LWIP_IPV6_NUM_ADDRESSES         3
2488 #endif
2489 
2490 /**
2491  * LWIP_IPV6_FORWARD==1: Forward IPv6 packets across netifs
2492  */
2493 #if !defined LWIP_IPV6_FORWARD || defined __DOXYGEN__
2494 #define LWIP_IPV6_FORWARD               0
2495 #endif
2496 
2497 /**
2498  * LWIP_IPV6_FRAG==1: Fragment outgoing IPv6 packets that are too big.
2499  */
2500 #if !defined LWIP_IPV6_FRAG || defined __DOXYGEN__
2501 #define LWIP_IPV6_FRAG                  1
2502 #endif
2503 
2504 /**
2505  * LWIP_IPV6_REASS==1: reassemble incoming IPv6 packets that fragmented
2506  */
2507 #if !defined LWIP_IPV6_REASS || defined __DOXYGEN__
2508 #define LWIP_IPV6_REASS                 LWIP_IPV6
2509 #endif
2510 
2511 /**
2512  * LWIP_IPV6_SEND_ROUTER_SOLICIT==1: Send router solicitation messages during
2513  * network startup.
2514  */
2515 #if !defined LWIP_IPV6_SEND_ROUTER_SOLICIT || defined __DOXYGEN__
2516 #define LWIP_IPV6_SEND_ROUTER_SOLICIT   LWIP_IPV6
2517 #endif
2518 
2519 /**
2520  * LWIP_IPV6_AUTOCONFIG==1: Enable stateless address autoconfiguration as per RFC 4862.
2521  */
2522 #if !defined LWIP_IPV6_AUTOCONFIG || defined __DOXYGEN__
2523 #define LWIP_IPV6_AUTOCONFIG            LWIP_IPV6
2524 #endif
2525 
2526 /**
2527  * LWIP_IPV6_ADDRESS_LIFETIMES==1: Keep valid and preferred lifetimes for each
2528  * IPv6 address. Required for LWIP_IPV6_AUTOCONFIG. May still be enabled
2529  * otherwise, in which case the application may assign address lifetimes with
2530  * the appropriate macros. Addresses with no lifetime are assumed to be static.
2531  * If this option is disabled, all addresses are assumed to be static.
2532  */
2533 #if !defined LWIP_IPV6_ADDRESS_LIFETIMES || defined __DOXYGEN__
2534 #define LWIP_IPV6_ADDRESS_LIFETIMES     LWIP_IPV6_AUTOCONFIG
2535 #endif
2536 
2537 /**
2538  * LWIP_IPV6_DUP_DETECT_ATTEMPTS=[0..7]: Number of duplicate address detection attempts.
2539  */
2540 #if !defined LWIP_IPV6_DUP_DETECT_ATTEMPTS || defined __DOXYGEN__
2541 #define LWIP_IPV6_DUP_DETECT_ATTEMPTS   1
2542 #endif
2543 /**
2544  * @}
2545  */
2546 
2547 /**
2548  * @defgroup lwip_opts_icmp6 ICMP6
2549  * @ingroup lwip_opts_ipv6
2550  * @{
2551  */
2552 /**
2553  * LWIP_ICMP6==1: Enable ICMPv6 (mandatory per RFC)
2554  */
2555 #if !defined LWIP_ICMP6 || defined __DOXYGEN__
2556 #define LWIP_ICMP6                      LWIP_IPV6
2557 #endif
2558 
2559 /**
2560  * LWIP_ICMP6_DATASIZE: bytes from original packet to send back in
2561  * ICMPv6 error messages (0 = default of IP6_MIN_MTU_LENGTH)
2562  * ATTENTION: RFC4443 section 2.4 says IP6_MIN_MTU_LENGTH is a MUST,
2563  * so override this only if you absolutely have to!
2564  */
2565 #if !defined LWIP_ICMP6_DATASIZE || defined __DOXYGEN__
2566 #define LWIP_ICMP6_DATASIZE             0
2567 #endif
2568 
2569 /**
2570  * LWIP_ICMP6_HL: default hop limit for ICMPv6 messages
2571  */
2572 #if !defined LWIP_ICMP6_HL || defined __DOXYGEN__
2573 #define LWIP_ICMP6_HL                   255
2574 #endif
2575 /**
2576  * @}
2577  */
2578 
2579 /**
2580  * @defgroup lwip_opts_mld6 Multicast listener discovery
2581  * @ingroup lwip_opts_ipv6
2582  * @{
2583  */
2584 /**
2585  * LWIP_IPV6_MLD==1: Enable multicast listener discovery protocol.
2586  * If LWIP_IPV6 is enabled but this setting is disabled, the MAC layer must
2587  * indiscriminately pass all inbound IPv6 multicast traffic to lwIP.
2588  */
2589 #if !defined LWIP_IPV6_MLD || defined __DOXYGEN__
2590 #define LWIP_IPV6_MLD                   LWIP_IPV6
2591 #endif
2592 
2593 /**
2594  * MEMP_NUM_MLD6_GROUP: Max number of IPv6 multicast groups that can be joined.
2595  * There must be enough groups so that each netif can join the solicited-node
2596  * multicast group for each of its local addresses, plus one for MDNS if
2597  * applicable, plus any number of groups to be joined on UDP sockets.
2598  */
2599 #if !defined MEMP_NUM_MLD6_GROUP || defined __DOXYGEN__
2600 #define MEMP_NUM_MLD6_GROUP             4
2601 #endif
2602 /**
2603  * @}
2604  */
2605 
2606 /**
2607  * @defgroup lwip_opts_nd6 Neighbor discovery
2608  * @ingroup lwip_opts_ipv6
2609  * @{
2610  */
2611 /**
2612  * LWIP_ND6_QUEUEING==1: queue outgoing IPv6 packets while MAC address
2613  * is being resolved.
2614  */
2615 #if !defined LWIP_ND6_QUEUEING || defined __DOXYGEN__
2616 #define LWIP_ND6_QUEUEING               LWIP_IPV6
2617 #endif
2618 
2619 /**
2620  * MEMP_NUM_ND6_QUEUE: Max number of IPv6 packets to queue during MAC resolution.
2621  */
2622 #if !defined MEMP_NUM_ND6_QUEUE || defined __DOXYGEN__
2623 #define MEMP_NUM_ND6_QUEUE              20
2624 #endif
2625 
2626 /**
2627  * LWIP_ND6_NUM_NEIGHBORS: Number of entries in IPv6 neighbor cache
2628  */
2629 #if !defined LWIP_ND6_NUM_NEIGHBORS || defined __DOXYGEN__
2630 #define LWIP_ND6_NUM_NEIGHBORS          10
2631 #endif
2632 
2633 /**
2634  * LWIP_ND6_NUM_DESTINATIONS: number of entries in IPv6 destination cache
2635  */
2636 #if !defined LWIP_ND6_NUM_DESTINATIONS || defined __DOXYGEN__
2637 #define LWIP_ND6_NUM_DESTINATIONS       10
2638 #endif
2639 
2640 /**
2641  * LWIP_ND6_NUM_PREFIXES: number of entries in IPv6 on-link prefixes cache
2642  */
2643 #if !defined LWIP_ND6_NUM_PREFIXES || defined __DOXYGEN__
2644 #define LWIP_ND6_NUM_PREFIXES           5
2645 #endif
2646 
2647 /**
2648  * LWIP_ND6_NUM_ROUTERS: number of entries in IPv6 default router cache
2649  */
2650 #if !defined LWIP_ND6_NUM_ROUTERS || defined __DOXYGEN__
2651 #define LWIP_ND6_NUM_ROUTERS            3
2652 #endif
2653 
2654 /**
2655  * LWIP_ND6_MAX_MULTICAST_SOLICIT: max number of multicast solicit messages to send
2656  * (neighbor solicit and router solicit)
2657  */
2658 #if !defined LWIP_ND6_MAX_MULTICAST_SOLICIT || defined __DOXYGEN__
2659 #define LWIP_ND6_MAX_MULTICAST_SOLICIT  3
2660 #endif
2661 
2662 /**
2663  * LWIP_ND6_MAX_UNICAST_SOLICIT: max number of unicast neighbor solicitation messages
2664  * to send during neighbor reachability detection.
2665  */
2666 #if !defined LWIP_ND6_MAX_UNICAST_SOLICIT || defined __DOXYGEN__
2667 #define LWIP_ND6_MAX_UNICAST_SOLICIT    3
2668 #endif
2669 
2670 /**
2671  * Unused: See ND RFC (time in milliseconds).
2672  */
2673 #if !defined LWIP_ND6_MAX_ANYCAST_DELAY_TIME || defined __DOXYGEN__
2674 #define LWIP_ND6_MAX_ANYCAST_DELAY_TIME 1000
2675 #endif
2676 
2677 /**
2678  * Unused: See ND RFC
2679  */
2680 #if !defined LWIP_ND6_MAX_NEIGHBOR_ADVERTISEMENT || defined __DOXYGEN__
2681 #define LWIP_ND6_MAX_NEIGHBOR_ADVERTISEMENT  3
2682 #endif
2683 
2684 /**
2685  * LWIP_ND6_REACHABLE_TIME: default neighbor reachable time (in milliseconds).
2686  * May be updated by router advertisement messages.
2687  */
2688 #if !defined LWIP_ND6_REACHABLE_TIME || defined __DOXYGEN__
2689 #define LWIP_ND6_REACHABLE_TIME         30000
2690 #endif
2691 
2692 /**
2693  * LWIP_ND6_RETRANS_TIMER: default retransmission timer for solicitation messages
2694  */
2695 #if !defined LWIP_ND6_RETRANS_TIMER || defined __DOXYGEN__
2696 #define LWIP_ND6_RETRANS_TIMER          1000
2697 #endif
2698 
2699 /**
2700  * LWIP_ND6_DELAY_FIRST_PROBE_TIME: Delay before first unicast neighbor solicitation
2701  * message is sent, during neighbor reachability detection.
2702  */
2703 #if !defined LWIP_ND6_DELAY_FIRST_PROBE_TIME || defined __DOXYGEN__
2704 #define LWIP_ND6_DELAY_FIRST_PROBE_TIME 5000
2705 #endif
2706 
2707 /**
2708  * LWIP_ND6_ALLOW_RA_UPDATES==1: Allow Router Advertisement messages to update
2709  * Reachable time and retransmission timers, and netif MTU.
2710  */
2711 #if !defined LWIP_ND6_ALLOW_RA_UPDATES || defined __DOXYGEN__
2712 #define LWIP_ND6_ALLOW_RA_UPDATES       1
2713 #endif
2714 
2715 /**
2716  * LWIP_ND6_TCP_REACHABILITY_HINTS==1: Allow TCP to provide Neighbor Discovery
2717  * with reachability hints for connected destinations. This helps avoid sending
2718  * unicast neighbor solicitation messages.
2719  */
2720 #if !defined LWIP_ND6_TCP_REACHABILITY_HINTS || defined __DOXYGEN__
2721 #define LWIP_ND6_TCP_REACHABILITY_HINTS 1
2722 #endif
2723 
2724 /**
2725  * LWIP_ND6_RDNSS_MAX_DNS_SERVERS > 0: Use IPv6 Router Advertisement Recursive
2726  * DNS Server Option (as per RFC 6106) to copy a defined maximum number of DNS
2727  * servers to the DNS module.
2728  */
2729 #if !defined LWIP_ND6_RDNSS_MAX_DNS_SERVERS || defined __DOXYGEN__
2730 #define LWIP_ND6_RDNSS_MAX_DNS_SERVERS  0
2731 #endif
2732 /**
2733  * @}
2734  */
2735 
2736 /**
2737  * @defgroup lwip_opts_dhcpv6 DHCPv6
2738  * @ingroup lwip_opts_ipv6
2739  * @{
2740  */
2741 /**
2742  * LWIP_IPV6_DHCP6==1: enable DHCPv6 stateful/stateless address autoconfiguration.
2743  */
2744 #if !defined LWIP_IPV6_DHCP6 || defined __DOXYGEN__
2745 #define LWIP_IPV6_DHCP6                 0
2746 #endif
2747 
2748 /**
2749  * LWIP_IPV6_DHCP6_STATEFUL==1: enable DHCPv6 stateful address autoconfiguration.
2750  * (not supported, yet!)
2751  */
2752 #if !defined LWIP_IPV6_DHCP6_STATEFUL || defined __DOXYGEN__
2753 #define LWIP_IPV6_DHCP6_STATEFUL        0
2754 #endif
2755 
2756 /**
2757  * LWIP_IPV6_DHCP6_STATELESS==1: enable DHCPv6 stateless address autoconfiguration.
2758  */
2759 #if !defined LWIP_IPV6_DHCP6_STATELESS || defined __DOXYGEN__
2760 #define LWIP_IPV6_DHCP6_STATELESS       LWIP_IPV6_DHCP6
2761 #endif
2762 
2763 /**
2764  * LWIP_DHCP6_GETS_NTP==1: Request NTP servers via DHCPv6. For each
2765  * response packet, a callback is called, which has to be provided by the port:
2766  * void dhcp6_set_ntp_servers(u8_t num_ntp_servers, ip_addr_t* ntp_server_addrs);
2767 */
2768 #if !defined LWIP_DHCP6_GET_NTP_SRV || defined __DOXYGEN__
2769 #define LWIP_DHCP6_GET_NTP_SRV          0
2770 #endif
2771 
2772 /**
2773  * The maximum of NTP servers requested
2774  */
2775 #if !defined LWIP_DHCP6_MAX_NTP_SERVERS || defined __DOXYGEN__
2776 #define LWIP_DHCP6_MAX_NTP_SERVERS      1
2777 #endif
2778 
2779 /**
2780  * LWIP_DHCP6_MAX_DNS_SERVERS > 0: Request DNS servers via DHCPv6.
2781  * DNS servers received in the response are passed to DNS via @ref dns_setserver()
2782  * (up to the maximum limit defined here).
2783  */
2784 #if !defined LWIP_DHCP6_MAX_DNS_SERVERS || defined __DOXYGEN__
2785 #define LWIP_DHCP6_MAX_DNS_SERVERS      DNS_MAX_SERVERS
2786 #endif
2787 /**
2788  * @}
2789  */
2790 
2791 /*
2792    ---------------------------------------
2793    ---------- Hook options ---------------
2794    ---------------------------------------
2795 */
2796 
2797 /**
2798  * @defgroup lwip_opts_hooks Hooks
2799  * @ingroup lwip_opts_infrastructure
2800  * Hooks are undefined by default, define them to a function if you need them.
2801  * @{
2802  */
2803 
2804 /**
2805  * LWIP_HOOK_FILENAME: Custom filename to \#include in files that provide hooks.
2806  * Declare your hook function prototypes in there, you may also \#include all headers
2807  * providing data types that are need in this file.
2808  */
2809 #ifdef __DOXYGEN__
2810 #define LWIP_HOOK_FILENAME "path/to/my/lwip_hooks.h"
2811 #endif
2812 
2813 /**
2814  * LWIP_HOOK_TCP_ISN:
2815  * Hook for generation of the Initial Sequence Number (ISN) for a new TCP
2816  * connection. The default lwIP ISN generation algorithm is very basic and may
2817  * allow for TCP spoofing attacks. This hook provides the means to implement
2818  * the standardized ISN generation algorithm from RFC 6528 (see contrib/adons/tcp_isn),
2819  * or any other desired algorithm as a replacement.
2820  * Called from tcp_connect() and tcp_listen_input() when an ISN is needed for
2821  * a new TCP connection, if TCP support (@ref LWIP_TCP) is enabled.<br>
2822  * Signature:\code{.c}
2823  * u32_t my_hook_tcp_isn(const ip_addr_t* local_ip, u16_t local_port, const ip_addr_t* remote_ip, u16_t remote_port);
2824  * \endcode
2825  * - it may be necessary to use "struct ip_addr" (ip4_addr, ip6_addr) instead of "ip_addr_t" in function declarations<br>
2826  * Arguments:
2827  * - local_ip: pointer to the local IP address of the connection
2828  * - local_port: local port number of the connection (host-byte order)
2829  * - remote_ip: pointer to the remote IP address of the connection
2830  * - remote_port: remote port number of the connection (host-byte order)<br>
2831  * Return value:
2832  * - the 32-bit Initial Sequence Number to use for the new TCP connection.
2833  */
2834 #ifdef __DOXYGEN__
2835 #define LWIP_HOOK_TCP_ISN(local_ip, local_port, remote_ip, remote_port)
2836 #endif
2837 
2838 /**
2839  * LWIP_HOOK_TCP_INPACKET_PCB:
2840  * Hook for intercepting incoming packets before they are passed to a pcb. This
2841  * allows updating some state or even dropping a packet.
2842  * Signature:\code{.c}
2843  * err_t my_hook_tcp_inpkt(struct tcp_pcb *pcb, struct tcp_hdr *hdr, u16_t optlen, u16_t opt1len, u8_t *opt2, struct pbuf *p);
2844  * \endcode
2845  * Arguments:
2846  * - pcb: tcp_pcb selected for input of this packet (ATTENTION: this may be
2847  *        struct tcp_pcb_listen if pcb->state == LISTEN)
2848  * - hdr: pointer to tcp header (ATTENTION: tcp options may not be in one piece!)
2849  * - optlen: tcp option length
2850  * - opt1len: tcp option length 1st part
2851  * - opt2: if this is != NULL, tcp options are split among 2 pbufs. In that case,
2852  *         options start at right after the tcp header ('(u8_t*)(hdr + 1)') for
2853  *         the first 'opt1len' bytes and the rest starts at 'opt2'. opt2len can
2854  *         be simply calculated: 'opt2len = optlen - opt1len;'
2855  * - p: input packet, p->payload points to application data (that's why tcp hdr
2856  *      and options are passed in separately)
2857  * Return value:
2858  * - ERR_OK: continue input of this packet as normal
2859  * - != ERR_OK: drop this packet for input (don't continue input processing)
2860  *
2861  * ATTENTION: don't call any tcp api functions that might change tcp state (pcb
2862  * state or any pcb lists) from this callback!
2863  */
2864 #ifdef __DOXYGEN__
2865 #define LWIP_HOOK_TCP_INPACKET_PCB(pcb, hdr, optlen, opt1len, opt2, p)
2866 #endif
2867 
2868 /**
2869  * LWIP_HOOK_TCP_OUT_TCPOPT_LENGTH:
2870  * Hook for increasing the size of the options allocated with a tcp header.
2871  * Together with LWIP_HOOK_TCP_OUT_ADD_TCPOPTS, this can be used to add custom
2872  * options to outgoing tcp segments.
2873  * Signature:\code{.c}
2874  * u8_t my_hook_tcp_out_tcpopt_length(const struct tcp_pcb *pcb, u8_t internal_option_length);
2875  * \endcode
2876  * Arguments:
2877  * - pcb: tcp_pcb that transmits (ATTENTION: this may be NULL or
2878  *        struct tcp_pcb_listen if pcb->state == LISTEN)
2879  * - internal_option_length: tcp option length used by the stack internally
2880  * Return value:
2881  * - a number of bytes to allocate for tcp options (internal_option_length <= ret <= 40)
2882  *
2883  * ATTENTION: don't call any tcp api functions that might change tcp state (pcb
2884  * state or any pcb lists) from this callback!
2885  */
2886 #ifdef __DOXYGEN__
2887 #define LWIP_HOOK_TCP_OUT_TCPOPT_LENGTH(pcb, internal_len)
2888 #endif
2889 
2890 /**
2891  * LWIP_HOOK_TCP_OUT_ADD_TCPOPTS:
2892  * Hook for adding custom options to outgoing tcp segments.
2893  * Space for these custom options has to be reserved via LWIP_HOOK_TCP_OUT_TCPOPT_LENGTH.
2894  * Signature:\code{.c}
2895  * u32_t *my_hook_tcp_out_add_tcpopts(struct pbuf *p, struct tcp_hdr *hdr, const struct tcp_pcb *pcb, u32_t *opts);
2896  * \endcode
2897  * Arguments:
2898  * - p: output packet, p->payload pointing to tcp header, data follows
2899  * - hdr: tcp header
2900  * - pcb: tcp_pcb that transmits (ATTENTION: this may be NULL or
2901  *        struct tcp_pcb_listen if pcb->state == LISTEN)
2902  * - opts: pointer where to add the custom options (there may already be options
2903  *         between the header and these)
2904  * Return value:
2905  * - pointer pointing directly after the inserted options
2906  *
2907  * ATTENTION: don't call any tcp api functions that might change tcp state (pcb
2908  * state or any pcb lists) from this callback!
2909  */
2910 #ifdef __DOXYGEN__
2911 #define LWIP_HOOK_TCP_OUT_ADD_TCPOPTS(p, hdr, pcb, opts)
2912 #endif
2913 
2914 /**
2915  * LWIP_HOOK_IP4_INPUT(pbuf, input_netif):
2916  * Called from ip_input() (IPv4)
2917  * Signature:\code{.c}
2918  *   int my_hook(struct pbuf *pbuf, struct netif *input_netif);
2919  * \endcode
2920  * Arguments:
2921  * - pbuf: received struct pbuf passed to ip_input()
2922  * - input_netif: struct netif on which the packet has been received
2923  * Return values:
2924  * - 0: Hook has not consumed the packet, packet is processed as normal
2925  * - != 0: Hook has consumed the packet.
2926  * If the hook consumed the packet, 'pbuf' is in the responsibility of the hook
2927  * (i.e. free it when done).
2928  */
2929 #ifdef __DOXYGEN__
2930 #define LWIP_HOOK_IP4_INPUT(pbuf, input_netif)
2931 #endif
2932 
2933 /**
2934  * LWIP_HOOK_IP4_ROUTE(dest):
2935  * Called from ip_route() (IPv4)
2936  * Signature:\code{.c}
2937  *   struct netif *my_hook(const ip4_addr_t *dest);
2938  * \endcode
2939  * Arguments:
2940  * - dest: destination IPv4 address
2941  * Returns values:
2942  * - the destination netif
2943  * - NULL if no destination netif is found. In that case, ip_route() continues as normal.
2944  */
2945 #ifdef __DOXYGEN__
2946 #define LWIP_HOOK_IP4_ROUTE()
2947 #endif
2948 
2949 /**
2950  * LWIP_HOOK_IP4_ROUTE_SRC(src, dest):
2951  * Source-based routing for IPv4 - called from ip_route() (IPv4)
2952  * Signature:\code{.c}
2953  *   struct netif *my_hook(const ip4_addr_t *src, const ip4_addr_t *dest);
2954  * \endcode
2955  * Arguments:
2956  * - src: local/source IPv4 address
2957  * - dest: destination IPv4 address
2958  * Returns values:
2959  * - the destination netif
2960  * - NULL if no destination netif is found. In that case, ip_route() continues as normal.
2961  */
2962 #ifdef __DOXYGEN__
2963 #define LWIP_HOOK_IP4_ROUTE_SRC(src, dest)
2964 #endif
2965 
2966 /**
2967  * LWIP_HOOK_IP4_CANFORWARD(src, dest):
2968  * Check if an IPv4 can be forwarded - called from:
2969  * ip4_input() -> ip4_forward() -> ip4_canforward() (IPv4)
2970  * - source address is available via ip4_current_src_addr()
2971  * - calling an output function in this context (e.g. multicast router) is allowed
2972  * Signature:\code{.c}
2973  *   int my_hook(struct pbuf *p, u32_t dest_addr_hostorder);
2974  * \endcode
2975  * Arguments:
2976  * - p: packet to forward
2977  * - dest: destination IPv4 address
2978  * Returns values:
2979  * - 1: forward
2980  * - 0: don't forward
2981  * - -1: no decision. In that case, ip4_canforward() continues as normal.
2982  */
2983 #ifdef __DOXYGEN__
2984 #define LWIP_HOOK_IP4_CANFORWARD(src, dest)
2985 #endif
2986 
2987 /**
2988  * LWIP_HOOK_ETHARP_GET_GW(netif, dest):
2989  * Called from etharp_output() (IPv4)
2990  * Signature:\code{.c}
2991  *   const ip4_addr_t *my_hook(struct netif *netif, const ip4_addr_t *dest);
2992  * \endcode
2993  * Arguments:
2994  * - netif: the netif used for sending
2995  * - dest: the destination IPv4 address
2996  * Return values:
2997  * - the IPv4 address of the gateway to handle the specified destination IPv4 address
2998  * - NULL, in which case the netif's default gateway is used
2999  *
3000  * The returned address MUST be directly reachable on the specified netif!
3001  * This function is meant to implement advanced IPv4 routing together with
3002  * LWIP_HOOK_IP4_ROUTE(). The actual routing/gateway table implementation is
3003  * not part of lwIP but can e.g. be hidden in the netif's state argument.
3004 */
3005 #ifdef __DOXYGEN__
3006 #define LWIP_HOOK_ETHARP_GET_GW(netif, dest)
3007 #endif
3008 
3009 /**
3010  * LWIP_HOOK_IP6_INPUT(pbuf, input_netif):
3011  * Called from ip6_input() (IPv6)
3012  * Signature:\code{.c}
3013  *   int my_hook(struct pbuf *pbuf, struct netif *input_netif);
3014  * \endcode
3015  * Arguments:
3016  * - pbuf: received struct pbuf passed to ip6_input()
3017  * - input_netif: struct netif on which the packet has been received
3018  * Return values:
3019  * - 0: Hook has not consumed the packet, packet is processed as normal
3020  * - != 0: Hook has consumed the packet.
3021  * If the hook consumed the packet, 'pbuf' is in the responsibility of the hook
3022  * (i.e. free it when done).
3023  */
3024 #ifdef __DOXYGEN__
3025 #define LWIP_HOOK_IP6_INPUT(pbuf, input_netif)
3026 #endif
3027 
3028 /**
3029  * LWIP_HOOK_IP6_ROUTE(src, dest):
3030  * Called from ip_route() (IPv6)
3031  * Signature:\code{.c}
3032  *   struct netif *my_hook(const ip6_addr_t *dest, const ip6_addr_t *src);
3033  * \endcode
3034  * Arguments:
3035  * - src: source IPv6 address
3036  * - dest: destination IPv6 address
3037  * Return values:
3038  * - the destination netif
3039  * - NULL if no destination netif is found. In that case, ip6_route() continues as normal.
3040  */
3041 #ifdef __DOXYGEN__
3042 #define LWIP_HOOK_IP6_ROUTE(src, dest)
3043 #endif
3044 
3045 /**
3046  * LWIP_HOOK_ND6_GET_GW(netif, dest):
3047  * Called from nd6_get_next_hop_entry() (IPv6)
3048  * Signature:\code{.c}
3049  *   const ip6_addr_t *my_hook(struct netif *netif, const ip6_addr_t *dest);
3050  * \endcode
3051  * Arguments:
3052  * - netif: the netif used for sending
3053  * - dest: the destination IPv6 address
3054  * Return values:
3055  * - the IPv6 address of the next hop to handle the specified destination IPv6 address
3056  * - NULL, in which case a NDP-discovered router is used instead
3057  *
3058  * The returned address MUST be directly reachable on the specified netif!
3059  * This function is meant to implement advanced IPv6 routing together with
3060  * LWIP_HOOK_IP6_ROUTE(). The actual routing/gateway table implementation is
3061  * not part of lwIP but can e.g. be hidden in the netif's state argument.
3062 */
3063 #ifdef __DOXYGEN__
3064 #define LWIP_HOOK_ND6_GET_GW(netif, dest)
3065 #endif
3066 
3067 /**
3068  * LWIP_HOOK_VLAN_CHECK(netif, eth_hdr, vlan_hdr):
3069  * Called from ethernet_input() if VLAN support is enabled
3070  * Signature:\code{.c}
3071  *   int my_hook(struct netif *netif, struct eth_hdr *eth_hdr, struct eth_vlan_hdr *vlan_hdr);
3072  * \endcode
3073  * Arguments:
3074  * - netif: struct netif on which the packet has been received
3075  * - eth_hdr: struct eth_hdr of the packet
3076  * - vlan_hdr: struct eth_vlan_hdr of the packet
3077  * Return values:
3078  * - 0: Packet must be dropped.
3079  * - != 0: Packet must be accepted.
3080  */
3081 #ifdef __DOXYGEN__
3082 #define LWIP_HOOK_VLAN_CHECK(netif, eth_hdr, vlan_hdr)
3083 #endif
3084 
3085 /**
3086  * LWIP_HOOK_VLAN_SET:
3087  * Hook can be used to set prio_vid field of vlan_hdr. If you need to store data
3088  * on per-netif basis to implement this callback, see @ref netif_cd.
3089  * Called from ethernet_output() if VLAN support (@ref ETHARP_SUPPORT_VLAN) is enabled.<br>
3090  * Signature:\code{.c}
3091  *   s32_t my_hook_vlan_set(struct netif* netif, struct pbuf* pbuf, const struct eth_addr* src, const struct eth_addr* dst, u16_t eth_type);
3092  * \endcode
3093  * Arguments:
3094  * - netif: struct netif that the packet will be sent through
3095  * - p: struct pbuf packet to be sent
3096  * - src: source eth address
3097  * - dst: destination eth address
3098  * - eth_type: ethernet type to packet to be sent<br>
3099  *
3100  *
3101  * Return values:
3102  * - &lt;0: Packet shall not contain VLAN header.
3103  * - 0 &lt;= return value &lt;= 0xFFFF: Packet shall contain VLAN header. Return value is prio_vid in host byte order.
3104  */
3105 #ifdef __DOXYGEN__
3106 #define LWIP_HOOK_VLAN_SET(netif, p, src, dst, eth_type)
3107 #endif
3108 
3109 /**
3110  * LWIP_HOOK_MEMP_AVAILABLE(memp_t_type):
3111  * Called from memp_free() when a memp pool was empty and an item is now available
3112  * Signature:\code{.c}
3113  *   void my_hook(memp_t type);
3114  * \endcode
3115  */
3116 #ifdef __DOXYGEN__
3117 #define LWIP_HOOK_MEMP_AVAILABLE(memp_t_type)
3118 #endif
3119 
3120 /**
3121  * LWIP_HOOK_UNKNOWN_ETH_PROTOCOL(pbuf, netif):
3122  * Called from ethernet_input() when an unknown eth type is encountered.
3123  * Signature:\code{.c}
3124  *   err_t my_hook(struct pbuf* pbuf, struct netif* netif);
3125  * \endcode
3126  * Arguments:
3127  * - p: rx packet with unknown eth type
3128  * - netif: netif on which the packet has been received
3129  * Return values:
3130  * - ERR_OK if packet is accepted (hook function now owns the pbuf)
3131  * - any error code otherwise (pbuf is freed)
3132  *
3133  * Payload points to ethernet header!
3134  */
3135 #ifdef __DOXYGEN__
3136 #define LWIP_HOOK_UNKNOWN_ETH_PROTOCOL(pbuf, netif)
3137 #endif
3138 
3139 /**
3140  * LWIP_HOOK_DHCP_APPEND_OPTIONS(netif, dhcp, state, msg, msg_type, options_len_ptr):
3141  * Called from various dhcp functions when sending a DHCP message.
3142  * This hook is called just before the DHCP message trailer is added, so the
3143  * options are at the end of a DHCP message.
3144  * Signature:\code{.c}
3145  *   void my_hook(struct netif *netif, struct dhcp *dhcp, u8_t state, struct dhcp_msg *msg,
3146  *                u8_t msg_type, u16_t *options_len_ptr);
3147  * \endcode
3148  * Arguments:
3149  * - netif: struct netif that the packet will be sent through
3150  * - dhcp: struct dhcp on that netif
3151  * - state: current dhcp state (dhcp_state_enum_t as an u8_t)
3152  * - msg: struct dhcp_msg that will be sent
3153  * - msg_type: dhcp message type to be sent (u8_t)
3154  * - options_len_ptr: pointer to the current length of options in the dhcp_msg "msg"
3155  *                    (must be increased when options are added!)
3156  *
3157  * Options need to appended like this:
3158  *   LWIP_ASSERT("dhcp option overflow", *options_len_ptr + option_len + 2 <= DHCP_OPTIONS_LEN);
3159  *   msg->options[(*options_len_ptr)++] = &lt;option_number&gt;;
3160  *   msg->options[(*options_len_ptr)++] = &lt;option_len&gt;;
3161  *   msg->options[(*options_len_ptr)++] = &lt;option_bytes&gt;;
3162  *   [...]
3163  */
3164 #ifdef __DOXYGEN__
3165 #define LWIP_HOOK_DHCP_APPEND_OPTIONS(netif, dhcp, state, msg, msg_type, options_len_ptr)
3166 #endif
3167 
3168 /**
3169  * LWIP_HOOK_DHCP_PARSE_OPTION(netif, dhcp, state, msg, msg_type, option, len, pbuf, option_value_offset):
3170  * Called from dhcp_parse_reply when receiving a DHCP message.
3171  * This hook is called for every option in the received message that is not handled internally.
3172  * Signature:\code{.c}
3173  *   void my_hook(struct netif *netif, struct dhcp *dhcp, u8_t state, struct dhcp_msg *msg,
3174  *                u8_t msg_type, u8_t option, u8_t option_len, struct pbuf *pbuf, u16_t option_value_offset);
3175  * \endcode
3176  * Arguments:
3177  * - netif: struct netif that the packet will be sent through
3178  * - dhcp: struct dhcp on that netif
3179  * - state: current dhcp state (dhcp_state_enum_t as an u8_t)
3180  * - msg: struct dhcp_msg that was received
3181  * - msg_type: dhcp message type received (u8_t, ATTENTION: only valid after
3182  *             the message type option has been parsed!)
3183  * - option: option value (u8_t)
3184  * - len: option data length (u8_t)
3185  * - pbuf: pbuf where option data is contained
3186  * - option_value_offset: offset in pbuf where option data begins
3187  *
3188  * A nice way to get the option contents is pbuf_get_contiguous():
3189  *  u8_t buf[32];
3190  *  u8_t *ptr = (u8_t*)pbuf_get_contiguous(p, buf, sizeof(buf), LWIP_MIN(option_len, sizeof(buf)), offset);
3191  */
3192 #ifdef __DOXYGEN__
3193 #define LWIP_HOOK_DHCP_PARSE_OPTION(netif, dhcp, state, msg, msg_type, option, len, pbuf, offset)
3194 #endif
3195 
3196 /**
3197  * LWIP_HOOK_DHCP6_APPEND_OPTIONS(netif, dhcp6, state, msg, msg_type, options_len_ptr, max_len):
3198  * Called from various dhcp6 functions when sending a DHCP6 message.
3199  * This hook is called just before the DHCP6 message is sent, so the
3200  * options are at the end of a DHCP6 message.
3201  * Signature:\code{.c}
3202  *   void my_hook(struct netif *netif, struct dhcp6 *dhcp, u8_t state, struct dhcp6_msg *msg,
3203  *                u8_t msg_type, u16_t *options_len_ptr);
3204  * \endcode
3205  * Arguments:
3206  * - netif: struct netif that the packet will be sent through
3207  * - dhcp6: struct dhcp6 on that netif
3208  * - state: current dhcp6 state (dhcp6_state_enum_t as an u8_t)
3209  * - msg: struct dhcp6_msg that will be sent
3210  * - msg_type: dhcp6 message type to be sent (u8_t)
3211  * - options_len_ptr: pointer to the current length of options in the dhcp6_msg "msg"
3212  *                    (must be increased when options are added!)
3213  *
3214  * Options need to appended like this:
3215  *   u8_t *options = (u8_t *)(msg + 1);
3216  *   LWIP_ASSERT("dhcp option overflow", sizeof(struct dhcp6_msg) + *options_len_ptr + newoptlen <= max_len);
3217  *   options[(*options_len_ptr)++] = &lt;option_data&gt;;
3218  *   [...]
3219  */
3220 #ifdef __DOXYGEN__
3221 #define LWIP_HOOK_DHCP6_APPEND_OPTIONS(netif, dhcp6, state, msg, msg_type, options_len_ptr, max_len)
3222 #endif
3223 
3224 /**
3225  * LWIP_HOOK_SOCKETS_SETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3226  * Called from socket API to implement setsockopt() for options not provided by lwIP.
3227  * Core lock is held when this hook is called.
3228  * Signature:\code{.c}
3229  *   int my_hook(int s, struct lwip_sock *sock, int level, int optname, const void *optval, socklen_t optlen, int *err)
3230  * \endcode
3231  * Arguments:
3232  * - s: socket file descriptor
3233  * - sock: internal socket descriptor (see lwip/priv/sockets_priv.h)
3234  * - level: protocol level at which the option resides
3235  * - optname: option to set
3236  * - optval: value to set
3237  * - optlen: size of optval
3238  * - err: output error
3239  * Return values:
3240  * - 0: Hook has not consumed the option, code continues as normal (to internal options)
3241  * - != 0: Hook has consumed the option, 'err' is returned
3242  */
3243 #ifdef __DOXYGEN__
3244 #define LWIP_HOOK_SOCKETS_SETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3245 #endif
3246 
3247 /**
3248  * LWIP_HOOK_SOCKETS_GETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3249  * Called from socket API to implement getsockopt() for options not provided by lwIP.
3250  * Core lock is held when this hook is called.
3251  * Signature:\code{.c}
3252  *   int my_hook(int s, struct lwip_sock *sock, int level, int optname, void *optval, socklen_t *optlen, int *err)
3253  * \endcode
3254  * Arguments:
3255  * - s: socket file descriptor
3256  * - sock: internal socket descriptor (see lwip/priv/sockets_priv.h)
3257  * - level: protocol level at which the option resides
3258  * - optname: option to get
3259  * - optval: value to get
3260  * - optlen: size of optval
3261  * - err: output error
3262  * Return values:
3263  * - 0: Hook has not consumed the option, code continues as normal (to internal options)
3264  * - != 0: Hook has consumed the option, 'err' is returned
3265  */
3266 #ifdef __DOXYGEN__
3267 #define LWIP_HOOK_SOCKETS_GETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3268 #endif
3269 
3270 /**
3271  * LWIP_HOOK_NETCONN_EXTERNAL_RESOLVE(name, addr, addrtype, err)
3272  * Called from netconn APIs (not usable with callback apps) allowing an
3273  * external DNS resolver (which uses sequential API) to handle the query.
3274  * Signature:\code{.c}
3275  *   int my_hook(const char *name, ip_addr_t *addr, u8_t addrtype, err_t *err)
3276  * \endcode
3277  * Arguments:
3278  * - name: hostname to resolve
3279  * - addr: output host address
3280  * - addrtype: type of address to query
3281  * - err: output error
3282  * Return values:
3283  * - 0: Hook has not consumed hostname query, query continues into DNS module
3284  * - != 0: Hook has consumed the query
3285  *
3286  * err must also be checked to determine if the hook consumed the query, but
3287  * the query failed
3288  */
3289 #ifdef __DOXYGEN__
3290 #define LWIP_HOOK_NETCONN_EXTERNAL_RESOLVE(name, addr, addrtype, err)
3291 #endif
3292 /**
3293  * @}
3294  */
3295 
3296 /*
3297    ---------------------------------------
3298    ---------- Debugging options ----------
3299    ---------------------------------------
3300 */
3301 /**
3302  * @defgroup lwip_opts_debugmsg Debug messages
3303  * @ingroup lwip_opts_debug
3304  * @{
3305  */
3306 /**
3307  * LWIP_DBG_MIN_LEVEL: After masking, the value of the debug is
3308  * compared against this value. If it is smaller, then debugging
3309  * messages are written.
3310  * @see debugging_levels
3311  */
3312 #if !defined LWIP_DBG_MIN_LEVEL || defined __DOXYGEN__
3313 #define LWIP_DBG_MIN_LEVEL              LWIP_DBG_LEVEL_ALL
3314 #endif
3315 
3316 /**
3317  * LWIP_DBG_TYPES_ON: A mask that can be used to globally enable/disable
3318  * debug messages of certain types.
3319  * @see debugging_levels
3320  */
3321 #if !defined LWIP_DBG_TYPES_ON || defined __DOXYGEN__
3322 #define LWIP_DBG_TYPES_ON               LWIP_DBG_ON
3323 #endif
3324 
3325 /**
3326  * ETHARP_DEBUG: Enable debugging in etharp.c.
3327  */
3328 #if !defined ETHARP_DEBUG || defined __DOXYGEN__
3329 #define ETHARP_DEBUG                    LWIP_DBG_OFF
3330 #endif
3331 
3332 /**
3333  * NETIF_DEBUG: Enable debugging in netif.c.
3334  */
3335 #if !defined NETIF_DEBUG || defined __DOXYGEN__
3336 #define NETIF_DEBUG                     LWIP_DBG_OFF
3337 #endif
3338 
3339 /**
3340  * PBUF_DEBUG: Enable debugging in pbuf.c.
3341  */
3342 #if !defined PBUF_DEBUG || defined __DOXYGEN__
3343 #define PBUF_DEBUG                      LWIP_DBG_OFF
3344 #endif
3345 
3346 /**
3347  * API_LIB_DEBUG: Enable debugging in api_lib.c.
3348  */
3349 #if !defined API_LIB_DEBUG || defined __DOXYGEN__
3350 #define API_LIB_DEBUG                   LWIP_DBG_OFF
3351 #endif
3352 
3353 /**
3354  * API_MSG_DEBUG: Enable debugging in api_msg.c.
3355  */
3356 #if !defined API_MSG_DEBUG || defined __DOXYGEN__
3357 #define API_MSG_DEBUG                   LWIP_DBG_OFF
3358 #endif
3359 
3360 /**
3361  * SOCKETS_DEBUG: Enable debugging in sockets.c.
3362  */
3363 #if !defined SOCKETS_DEBUG || defined __DOXYGEN__
3364 #define SOCKETS_DEBUG                   LWIP_DBG_OFF
3365 #endif
3366 
3367 /**
3368  * ICMP_DEBUG: Enable debugging in icmp.c.
3369  */
3370 #if !defined ICMP_DEBUG || defined __DOXYGEN__
3371 #define ICMP_DEBUG                      LWIP_DBG_OFF
3372 #endif
3373 
3374 /**
3375  * IGMP_DEBUG: Enable debugging in igmp.c.
3376  */
3377 #if !defined IGMP_DEBUG || defined __DOXYGEN__
3378 #define IGMP_DEBUG                      LWIP_DBG_OFF
3379 #endif
3380 
3381 /**
3382  * INET_DEBUG: Enable debugging in inet.c.
3383  */
3384 #if !defined INET_DEBUG || defined __DOXYGEN__
3385 #define INET_DEBUG                      LWIP_DBG_OFF
3386 #endif
3387 
3388 /**
3389  * IP_DEBUG: Enable debugging for IP.
3390  */
3391 #if !defined IP_DEBUG || defined __DOXYGEN__
3392 #define IP_DEBUG                        LWIP_DBG_OFF
3393 #endif
3394 
3395 /**
3396  * IP_REASS_DEBUG: Enable debugging in ip_frag.c for both frag & reass.
3397  */
3398 #if !defined IP_REASS_DEBUG || defined __DOXYGEN__
3399 #define IP_REASS_DEBUG                  LWIP_DBG_OFF
3400 #endif
3401 
3402 /**
3403  * RAW_DEBUG: Enable debugging in raw.c.
3404  */
3405 #if !defined RAW_DEBUG || defined __DOXYGEN__
3406 #define RAW_DEBUG                       LWIP_DBG_OFF
3407 #endif
3408 
3409 /**
3410  * MEM_DEBUG: Enable debugging in mem.c.
3411  */
3412 #if !defined MEM_DEBUG || defined __DOXYGEN__
3413 #define MEM_DEBUG                       LWIP_DBG_OFF
3414 #endif
3415 
3416 /**
3417  * MEMP_DEBUG: Enable debugging in memp.c.
3418  */
3419 #if !defined MEMP_DEBUG || defined __DOXYGEN__
3420 #define MEMP_DEBUG                      LWIP_DBG_OFF
3421 #endif
3422 
3423 /**
3424  * SYS_DEBUG: Enable debugging in sys.c.
3425  */
3426 #if !defined SYS_DEBUG || defined __DOXYGEN__
3427 #define SYS_DEBUG                       LWIP_DBG_OFF
3428 #endif
3429 
3430 /**
3431  * TIMERS_DEBUG: Enable debugging in timers.c.
3432  */
3433 #if !defined TIMERS_DEBUG || defined __DOXYGEN__
3434 #define TIMERS_DEBUG                    LWIP_DBG_OFF
3435 #endif
3436 
3437 /**
3438  * TCP_DEBUG: Enable debugging for TCP.
3439  */
3440 #if !defined TCP_DEBUG || defined __DOXYGEN__
3441 #define TCP_DEBUG                       LWIP_DBG_OFF
3442 #endif
3443 
3444 /**
3445  * TCP_INPUT_DEBUG: Enable debugging in tcp_in.c for incoming debug.
3446  */
3447 #if !defined TCP_INPUT_DEBUG || defined __DOXYGEN__
3448 #define TCP_INPUT_DEBUG                 LWIP_DBG_OFF
3449 #endif
3450 
3451 /**
3452  * TCP_FR_DEBUG: Enable debugging in tcp_in.c for fast retransmit.
3453  */
3454 #if !defined TCP_FR_DEBUG || defined __DOXYGEN__
3455 #define TCP_FR_DEBUG                    LWIP_DBG_OFF
3456 #endif
3457 
3458 /**
3459  * TCP_RTO_DEBUG: Enable debugging in TCP for retransmit
3460  * timeout.
3461  */
3462 #if !defined TCP_RTO_DEBUG || defined __DOXYGEN__
3463 #define TCP_RTO_DEBUG                   LWIP_DBG_OFF
3464 #endif
3465 
3466 /**
3467  * TCP_CWND_DEBUG: Enable debugging for TCP congestion window.
3468  */
3469 #if !defined TCP_CWND_DEBUG || defined __DOXYGEN__
3470 #define TCP_CWND_DEBUG                  LWIP_DBG_OFF
3471 #endif
3472 
3473 /**
3474  * TCP_WND_DEBUG: Enable debugging in tcp_in.c for window updating.
3475  */
3476 #if !defined TCP_WND_DEBUG || defined __DOXYGEN__
3477 #define TCP_WND_DEBUG                   LWIP_DBG_OFF
3478 #endif
3479 
3480 /**
3481  * TCP_OUTPUT_DEBUG: Enable debugging in tcp_out.c output functions.
3482  */
3483 #if !defined TCP_OUTPUT_DEBUG || defined __DOXYGEN__
3484 #define TCP_OUTPUT_DEBUG                LWIP_DBG_OFF
3485 #endif
3486 
3487 /**
3488  * TCP_RST_DEBUG: Enable debugging for TCP with the RST message.
3489  */
3490 #if !defined TCP_RST_DEBUG || defined __DOXYGEN__
3491 #define TCP_RST_DEBUG                   LWIP_DBG_OFF
3492 #endif
3493 
3494 /**
3495  * TCP_QLEN_DEBUG: Enable debugging for TCP queue lengths.
3496  */
3497 #if !defined TCP_QLEN_DEBUG || defined __DOXYGEN__
3498 #define TCP_QLEN_DEBUG                  LWIP_DBG_OFF
3499 #endif
3500 
3501 /**
3502  * UDP_DEBUG: Enable debugging in UDP.
3503  */
3504 #if !defined UDP_DEBUG || defined __DOXYGEN__
3505 #define UDP_DEBUG                       LWIP_DBG_OFF
3506 #endif
3507 
3508 /**
3509  * TCPIP_DEBUG: Enable debugging in tcpip.c.
3510  */
3511 #if !defined TCPIP_DEBUG || defined __DOXYGEN__
3512 #define TCPIP_DEBUG                     LWIP_DBG_OFF
3513 #endif
3514 
3515 /**
3516  * SLIP_DEBUG: Enable debugging in slipif.c.
3517  */
3518 #if !defined SLIP_DEBUG || defined __DOXYGEN__
3519 #define SLIP_DEBUG                      LWIP_DBG_OFF
3520 #endif
3521 
3522 /**
3523  * DHCP_DEBUG: Enable debugging in dhcp.c.
3524  */
3525 #if !defined DHCP_DEBUG || defined __DOXYGEN__
3526 #define DHCP_DEBUG                      LWIP_DBG_OFF
3527 #endif
3528 
3529 /**
3530  * AUTOIP_DEBUG: Enable debugging in autoip.c.
3531  */
3532 #if !defined AUTOIP_DEBUG || defined __DOXYGEN__
3533 #define AUTOIP_DEBUG                    LWIP_DBG_OFF
3534 #endif
3535 
3536 /**
3537  * ACD_DEBUG: Enable debugging in acd.c.
3538  */
3539 #if !defined ACD_DEBUG || defined __DOXYGEN__
3540 #define ACD_DEBUG                       LWIP_DBG_OFF
3541 #endif
3542 
3543 /**
3544  * DNS_DEBUG: Enable debugging for DNS.
3545  */
3546 #if !defined DNS_DEBUG || defined __DOXYGEN__
3547 #define DNS_DEBUG                       LWIP_DBG_OFF
3548 #endif
3549 
3550 /**
3551  * IP6_DEBUG: Enable debugging for IPv6.
3552  */
3553 #if !defined IP6_DEBUG || defined __DOXYGEN__
3554 #define IP6_DEBUG                       LWIP_DBG_OFF
3555 #endif
3556 
3557 /**
3558  * DHCP6_DEBUG: Enable debugging in dhcp6.c.
3559  */
3560 #if !defined DHCP6_DEBUG || defined __DOXYGEN__
3561 #define DHCP6_DEBUG                     LWIP_DBG_OFF
3562 #endif
3563 /**
3564  * @}
3565  */
3566 
3567 /**
3568  * LWIP_TESTMODE: Changes to make unit test possible
3569  */
3570 #if !defined LWIP_TESTMODE
3571 #define LWIP_TESTMODE                   0
3572 #endif
3573 
3574 /*
3575    --------------------------------------------------
3576    ---------- Performance tracking options ----------
3577    --------------------------------------------------
3578 */
3579 /**
3580  * @defgroup lwip_opts_perf Performance
3581  * @ingroup lwip_opts_debug
3582  * @{
3583  */
3584 /**
3585  * LWIP_PERF: Enable performance testing for lwIP
3586  * (if enabled, arch/perf.h is included)
3587  */
3588 #if !defined LWIP_PERF || defined __DOXYGEN__
3589 #define LWIP_PERF                       0
3590 #endif
3591 /**
3592  * @}
3593  */
3594 
3595 #endif /* LWIP_HDR_OPT_H */
3596