xref: /btstack/3rd-party/lwip/core/src/include/lwip/opt.h (revision 97dc5e692c7d94a280158af58036a0efee5b0e56)
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 <[email protected]>
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  * Called as first thing in the lwIP TCPIP thread. Can be used in conjunction
232  * with @ref LWIP_ASSERT_CORE_LOCKED to check core locking.
233  * @see @ref multithreading
234  */
235 #if !defined LWIP_MARK_TCPIP_THREAD || defined __DOXYGEN__
236 #define LWIP_MARK_TCPIP_THREAD()
237 #endif
238 /**
239  * @}
240  */
241 
242 /*
243    ------------------------------------
244    ---------- Memory options ----------
245    ------------------------------------
246 */
247 /**
248  * @defgroup lwip_opts_mem Heap and memory pools
249  * @ingroup lwip_opts_infrastructure
250  * @{
251  */
252 /**
253  * MEM_LIBC_MALLOC==1: Use malloc/free/realloc provided by your C-library
254  * instead of the lwip internal allocator. Can save code size if you
255  * already use it.
256  */
257 #if !defined MEM_LIBC_MALLOC || defined __DOXYGEN__
258 #define MEM_LIBC_MALLOC                 0
259 #endif
260 
261 /**
262  * MEMP_MEM_MALLOC==1: Use mem_malloc/mem_free instead of the lwip pool allocator.
263  * Especially useful with MEM_LIBC_MALLOC but handle with care regarding execution
264  * speed (heap alloc can be much slower than pool alloc) and usage from interrupts
265  * (especially if your netif driver allocates PBUF_POOL pbufs for received frames
266  * from interrupt)!
267  * ATTENTION: Currently, this uses the heap for ALL pools (also for private pools,
268  * not only for internal pools defined in memp_std.h)!
269  */
270 #if !defined MEMP_MEM_MALLOC || defined __DOXYGEN__
271 #define MEMP_MEM_MALLOC                 0
272 #endif
273 
274 /**
275  * MEMP_MEM_INIT==1: Force use of memset to initialize pool memory.
276  * Useful if pool are moved in uninitialized section of memory. This will ensure
277  * default values in pcbs struct are well initialized in all conditions.
278  */
279 #if !defined MEMP_MEM_INIT || defined __DOXYGEN__
280 #define MEMP_MEM_INIT                   0
281 #endif
282 
283 /**
284  * MEM_ALIGNMENT: should be set to the alignment of the CPU
285  *    4 byte alignment -> \#define MEM_ALIGNMENT 4
286  *    2 byte alignment -> \#define MEM_ALIGNMENT 2
287  */
288 #if !defined MEM_ALIGNMENT || defined __DOXYGEN__
289 #define MEM_ALIGNMENT                   1
290 #endif
291 
292 /**
293  * MEM_SIZE: the size of the heap memory. If the application will send
294  * a lot of data that needs to be copied, this should be set high.
295  */
296 #if !defined MEM_SIZE || defined __DOXYGEN__
297 #define MEM_SIZE                        1600
298 #endif
299 
300 /**
301  * MEMP_OVERFLOW_CHECK: memp overflow protection reserves a configurable
302  * amount of bytes before and after each memp element in every pool and fills
303  * it with a prominent default value.
304  *    MEMP_OVERFLOW_CHECK == 0 no checking
305  *    MEMP_OVERFLOW_CHECK == 1 checks each element when it is freed
306  *    MEMP_OVERFLOW_CHECK >= 2 checks each element in every pool every time
307  *      memp_malloc() or memp_free() is called (useful but slow!)
308  */
309 #if !defined MEMP_OVERFLOW_CHECK || defined __DOXYGEN__
310 #define MEMP_OVERFLOW_CHECK             0
311 #endif
312 
313 /**
314  * MEMP_SANITY_CHECK==1: run a sanity check after each memp_free() to make
315  * sure that there are no cycles in the linked lists.
316  */
317 #if !defined MEMP_SANITY_CHECK || defined __DOXYGEN__
318 #define MEMP_SANITY_CHECK               0
319 #endif
320 
321 /**
322  * MEM_OVERFLOW_CHECK: mem overflow protection reserves a configurable
323  * amount of bytes before and after each heap allocation chunk and fills
324  * it with a prominent default value.
325  *    MEM_OVERFLOW_CHECK == 0 no checking
326  *    MEM_OVERFLOW_CHECK == 1 checks each element when it is freed
327  *    MEM_OVERFLOW_CHECK >= 2 checks all heap elements every time
328  *      mem_malloc() or mem_free() is called (useful but slow!)
329  */
330 #if !defined MEM_OVERFLOW_CHECK || defined __DOXYGEN__
331 #define MEM_OVERFLOW_CHECK              0
332 #endif
333 
334 /**
335  * MEM_SANITY_CHECK==1: run a sanity check after each mem_free() to make
336  * sure that the linked list of heap elements is not corrupted.
337  */
338 #if !defined MEM_SANITY_CHECK || defined __DOXYGEN__
339 #define MEM_SANITY_CHECK                0
340 #endif
341 
342 /**
343  * MEM_USE_POOLS==1: Use an alternative to malloc() by allocating from a set
344  * of memory pools of various sizes. When mem_malloc is called, an element of
345  * the smallest pool that can provide the length needed is returned.
346  * To use this, MEMP_USE_CUSTOM_POOLS also has to be enabled.
347  */
348 #if !defined MEM_USE_POOLS || defined __DOXYGEN__
349 #define MEM_USE_POOLS                   0
350 #endif
351 
352 /**
353  * MEM_USE_POOLS_TRY_BIGGER_POOL==1: if one malloc-pool is empty, try the next
354  * bigger pool - WARNING: THIS MIGHT WASTE MEMORY but it can make a system more
355  * reliable. */
356 #if !defined MEM_USE_POOLS_TRY_BIGGER_POOL || defined __DOXYGEN__
357 #define MEM_USE_POOLS_TRY_BIGGER_POOL   0
358 #endif
359 
360 /**
361  * MEMP_USE_CUSTOM_POOLS==1: whether to include a user file lwippools.h
362  * that defines additional pools beyond the "standard" ones required
363  * by lwIP. If you set this to 1, you must have lwippools.h in your
364  * include path somewhere.
365  */
366 #if !defined MEMP_USE_CUSTOM_POOLS || defined __DOXYGEN__
367 #define MEMP_USE_CUSTOM_POOLS           0
368 #endif
369 
370 /**
371  * Set this to 1 if you want to free PBUF_RAM pbufs (or call mem_free()) from
372  * interrupt context (or another context that doesn't allow waiting for a
373  * semaphore).
374  * If set to 1, mem_malloc will be protected by a semaphore and SYS_ARCH_PROTECT,
375  * while mem_free will only use SYS_ARCH_PROTECT. mem_malloc SYS_ARCH_UNPROTECTs
376  * with each loop so that mem_free can run.
377  *
378  * ATTENTION: As you can see from the above description, this leads to dis-/
379  * enabling interrupts often, which can be slow! Also, on low memory, mem_malloc
380  * can need longer.
381  *
382  * If you don't want that, at least for NO_SYS=0, you can still use the following
383  * functions to enqueue a deallocation call which then runs in the tcpip_thread
384  * context:
385  * - pbuf_free_callback(p);
386  * - mem_free_callback(m);
387  */
388 #if !defined LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT || defined __DOXYGEN__
389 #define LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT 0
390 #endif
391 /**
392  * @}
393  */
394 
395 /*
396    ------------------------------------------------
397    ---------- Internal Memory Pool Sizes ----------
398    ------------------------------------------------
399 */
400 /**
401  * @defgroup lwip_opts_memp Internal memory pools
402  * @ingroup lwip_opts_infrastructure
403  * @{
404  */
405 /**
406  * MEMP_NUM_PBUF: the number of memp struct pbufs (used for PBUF_ROM and PBUF_REF).
407  * If the application sends a lot of data out of ROM (or other static memory),
408  * this should be set high.
409  */
410 #if !defined MEMP_NUM_PBUF || defined __DOXYGEN__
411 #define MEMP_NUM_PBUF                   16
412 #endif
413 
414 /**
415  * MEMP_NUM_RAW_PCB: Number of raw connection PCBs
416  * (requires the LWIP_RAW option)
417  */
418 #if !defined MEMP_NUM_RAW_PCB || defined __DOXYGEN__
419 #define MEMP_NUM_RAW_PCB                4
420 #endif
421 
422 /**
423  * MEMP_NUM_UDP_PCB: the number of UDP protocol control blocks. One
424  * per active UDP "connection".
425  * (requires the LWIP_UDP option)
426  */
427 #if !defined MEMP_NUM_UDP_PCB || defined __DOXYGEN__
428 #define MEMP_NUM_UDP_PCB                4
429 #endif
430 
431 /**
432  * MEMP_NUM_TCP_PCB: the number of simultaneously active TCP connections.
433  * (requires the LWIP_TCP option)
434  */
435 #if !defined MEMP_NUM_TCP_PCB || defined __DOXYGEN__
436 #define MEMP_NUM_TCP_PCB                5
437 #endif
438 
439 /**
440  * MEMP_NUM_TCP_PCB_LISTEN: the number of listening TCP connections.
441  * (requires the LWIP_TCP option)
442  */
443 #if !defined MEMP_NUM_TCP_PCB_LISTEN || defined __DOXYGEN__
444 #define MEMP_NUM_TCP_PCB_LISTEN         8
445 #endif
446 
447 /**
448  * MEMP_NUM_TCP_SEG: the number of simultaneously queued TCP segments.
449  * (requires the LWIP_TCP option)
450  */
451 #if !defined MEMP_NUM_TCP_SEG || defined __DOXYGEN__
452 #define MEMP_NUM_TCP_SEG                16
453 #endif
454 
455 /**
456  * MEMP_NUM_ALTCP_PCB: the number of simultaneously active altcp layer pcbs.
457  * (requires the LWIP_ALTCP option)
458  * Connections with multiple layers require more than one altcp_pcb (e.g. TLS
459  * over TCP requires 2 altcp_pcbs, one for TLS and one for TCP).
460  */
461 #if !defined MEMP_NUM_ALTCP_PCB || defined __DOXYGEN__
462 #define MEMP_NUM_ALTCP_PCB              MEMP_NUM_TCP_PCB
463 #endif
464 
465 /**
466  * MEMP_NUM_REASSDATA: the number of IP packets simultaneously queued for
467  * reassembly (whole packets, not fragments!)
468  */
469 #if !defined MEMP_NUM_REASSDATA || defined __DOXYGEN__
470 #define MEMP_NUM_REASSDATA              5
471 #endif
472 
473 /**
474  * MEMP_NUM_FRAG_PBUF: the number of IP fragments simultaneously sent
475  * (fragments, not whole packets!).
476  * This is only used with LWIP_NETIF_TX_SINGLE_PBUF==0 and only has to be > 1
477  * with DMA-enabled MACs where the packet is not yet sent when netif->output
478  * returns.
479  */
480 #if !defined MEMP_NUM_FRAG_PBUF || defined __DOXYGEN__
481 #define MEMP_NUM_FRAG_PBUF              15
482 #endif
483 
484 /**
485  * MEMP_NUM_ARP_QUEUE: the number of simultaneously queued outgoing
486  * packets (pbufs) that are waiting for an ARP request (to resolve
487  * their destination address) to finish.
488  * (requires the ARP_QUEUEING option)
489  */
490 #if !defined MEMP_NUM_ARP_QUEUE || defined __DOXYGEN__
491 #define MEMP_NUM_ARP_QUEUE              30
492 #endif
493 
494 /**
495  * MEMP_NUM_IGMP_GROUP: The number of multicast groups whose network interfaces
496  * can be members at the same time (one per netif - allsystems group -, plus one
497  * per netif membership).
498  * (requires the LWIP_IGMP option)
499  */
500 #if !defined MEMP_NUM_IGMP_GROUP || defined __DOXYGEN__
501 #define MEMP_NUM_IGMP_GROUP             8
502 #endif
503 
504 /**
505  * The number of sys timeouts used by the core stack (not apps)
506  * The default number of timeouts is calculated here for all enabled modules.
507  */
508 #define LWIP_NUM_SYS_TIMEOUT_INTERNAL   (LWIP_TCP + IP_REASSEMBLY + LWIP_ARP + (2*LWIP_DHCP) + LWIP_AUTOIP + LWIP_IGMP + LWIP_DNS + PPP_NUM_TIMEOUTS + (LWIP_IPV6 * (1 + LWIP_IPV6_REASS + LWIP_IPV6_MLD)))
509 
510 /**
511  * MEMP_NUM_SYS_TIMEOUT: the number of simultaneously active timeouts.
512  * The default number of timeouts is calculated here for all enabled modules.
513  * The formula expects settings to be either '0' or '1'.
514  */
515 #if !defined MEMP_NUM_SYS_TIMEOUT || defined __DOXYGEN__
516 #define MEMP_NUM_SYS_TIMEOUT            LWIP_NUM_SYS_TIMEOUT_INTERNAL
517 #endif
518 
519 /**
520  * MEMP_NUM_NETBUF: the number of struct netbufs.
521  * (only needed if you use the sequential API, like api_lib.c)
522  */
523 #if !defined MEMP_NUM_NETBUF || defined __DOXYGEN__
524 #define MEMP_NUM_NETBUF                 2
525 #endif
526 
527 /**
528  * MEMP_NUM_NETCONN: the number of struct netconns.
529  * (only needed if you use the sequential API, like api_lib.c)
530  */
531 #if !defined MEMP_NUM_NETCONN || defined __DOXYGEN__
532 #define MEMP_NUM_NETCONN                4
533 #endif
534 
535 /**
536  * MEMP_NUM_SELECT_CB: the number of struct lwip_select_cb.
537  * (Only needed if you have LWIP_MPU_COMPATIBLE==1 and use the socket API.
538  * In that case, you need one per thread calling lwip_select.)
539  */
540 #if !defined MEMP_NUM_SELECT_CB || defined __DOXYGEN__
541 #define MEMP_NUM_SELECT_CB              4
542 #endif
543 
544 /**
545  * MEMP_NUM_TCPIP_MSG_API: the number of struct tcpip_msg, which are used
546  * for callback/timeout API communication.
547  * (only needed if you use tcpip.c)
548  */
549 #if !defined MEMP_NUM_TCPIP_MSG_API || defined __DOXYGEN__
550 #define MEMP_NUM_TCPIP_MSG_API          8
551 #endif
552 
553 /**
554  * MEMP_NUM_TCPIP_MSG_INPKT: the number of struct tcpip_msg, which are used
555  * for incoming packets.
556  * (only needed if you use tcpip.c)
557  */
558 #if !defined MEMP_NUM_TCPIP_MSG_INPKT || defined __DOXYGEN__
559 #define MEMP_NUM_TCPIP_MSG_INPKT        8
560 #endif
561 
562 /**
563  * MEMP_NUM_NETDB: the number of concurrently running lwip_addrinfo() calls
564  * (before freeing the corresponding memory using lwip_freeaddrinfo()).
565  */
566 #if !defined MEMP_NUM_NETDB || defined __DOXYGEN__
567 #define MEMP_NUM_NETDB                  1
568 #endif
569 
570 /**
571  * MEMP_NUM_LOCALHOSTLIST: the number of host entries in the local host list
572  * if DNS_LOCAL_HOSTLIST_IS_DYNAMIC==1.
573  */
574 #if !defined MEMP_NUM_LOCALHOSTLIST || defined __DOXYGEN__
575 #define MEMP_NUM_LOCALHOSTLIST          1
576 #endif
577 
578 /**
579  * PBUF_POOL_SIZE: the number of buffers in the pbuf pool.
580  */
581 #if !defined PBUF_POOL_SIZE || defined __DOXYGEN__
582 #define PBUF_POOL_SIZE                  16
583 #endif
584 
585 /** MEMP_NUM_API_MSG: the number of concurrently active calls to various
586  * socket, netconn, and tcpip functions
587  */
588 #if !defined MEMP_NUM_API_MSG || defined __DOXYGEN__
589 #define MEMP_NUM_API_MSG                MEMP_NUM_TCPIP_MSG_API
590 #endif
591 
592 /** MEMP_NUM_DNS_API_MSG: the number of concurrently active calls to netconn_gethostbyname
593  */
594 #if !defined MEMP_NUM_DNS_API_MSG || defined __DOXYGEN__
595 #define MEMP_NUM_DNS_API_MSG            MEMP_NUM_TCPIP_MSG_API
596 #endif
597 
598 /** MEMP_NUM_SOCKET_SETGETSOCKOPT_DATA: the number of concurrently active calls
599  * to getsockopt/setsockopt
600  */
601 #if !defined MEMP_NUM_SOCKET_SETGETSOCKOPT_DATA || defined __DOXYGEN__
602 #define MEMP_NUM_SOCKET_SETGETSOCKOPT_DATA MEMP_NUM_TCPIP_MSG_API
603 #endif
604 
605 /** MEMP_NUM_NETIFAPI_MSG: the number of concurrently active calls to the
606  * netifapi functions
607  */
608 #if !defined MEMP_NUM_NETIFAPI_MSG || defined __DOXYGEN__
609 #define MEMP_NUM_NETIFAPI_MSG           MEMP_NUM_TCPIP_MSG_API
610 #endif
611 /**
612  * @}
613  */
614 
615 /*
616    ---------------------------------
617    ---------- ARP options ----------
618    ---------------------------------
619 */
620 /**
621  * @defgroup lwip_opts_arp ARP
622  * @ingroup lwip_opts_ipv4
623  * @{
624  */
625 /**
626  * LWIP_ARP==1: Enable ARP functionality.
627  */
628 #if !defined LWIP_ARP || defined __DOXYGEN__
629 #define LWIP_ARP                        1
630 #endif
631 
632 /**
633  * ARP_TABLE_SIZE: Number of active MAC-IP address pairs cached.
634  */
635 #if !defined ARP_TABLE_SIZE || defined __DOXYGEN__
636 #define ARP_TABLE_SIZE                  10
637 #endif
638 
639 /** the time an ARP entry stays valid after its last update,
640  *  for ARP_TMR_INTERVAL = 1000, this is
641  *  (60 * 5) seconds = 5 minutes.
642  */
643 #if !defined ARP_MAXAGE || defined __DOXYGEN__
644 #define ARP_MAXAGE                      300
645 #endif
646 
647 /**
648  * ARP_QUEUEING==1: Multiple outgoing packets are queued during hardware address
649  * resolution. By default, only the most recent packet is queued per IP address.
650  * This is sufficient for most protocols and mainly reduces TCP connection
651  * startup time. Set this to 1 if you know your application sends more than one
652  * packet in a row to an IP address that is not in the ARP cache.
653  */
654 #if !defined ARP_QUEUEING || defined __DOXYGEN__
655 #define ARP_QUEUEING                    0
656 #endif
657 
658 /** The maximum number of packets which may be queued for each
659  *  unresolved address by other network layers. Defaults to 3, 0 means disabled.
660  *  Old packets are dropped, new packets are queued.
661  */
662 #if !defined ARP_QUEUE_LEN || defined __DOXYGEN__
663 #define ARP_QUEUE_LEN                   3
664 #endif
665 
666 /**
667  * ETHARP_SUPPORT_VLAN==1: support receiving and sending ethernet packets with
668  * VLAN header. See the description of LWIP_HOOK_VLAN_CHECK and
669  * LWIP_HOOK_VLAN_SET hooks to check/set VLAN headers.
670  * Additionally, you can define ETHARP_VLAN_CHECK to an u16_t VLAN ID to check.
671  * If ETHARP_VLAN_CHECK is defined, only VLAN-traffic for this VLAN is accepted.
672  * If ETHARP_VLAN_CHECK is not defined, all traffic is accepted.
673  * Alternatively, define a function/define ETHARP_VLAN_CHECK_FN(eth_hdr, vlan)
674  * that returns 1 to accept a packet or 0 to drop a packet.
675  */
676 #if !defined ETHARP_SUPPORT_VLAN || defined __DOXYGEN__
677 #define ETHARP_SUPPORT_VLAN             0
678 #endif
679 
680 /**
681  * LWIP_VLAN_PCP==1: Enable outgoing VLAN taggning of frames on a per-PCB basis
682  * for QoS purposes. With this feature enabled, each PCB has a new variable: "tci".
683  * (Tag Control Identifier). The TCI contains three fields: VID, CFI and PCP.
684  * VID is the VLAN ID, which should be set to zero.
685  * The "CFI" bit is used to enable or disable VLAN tags for the PCB.
686  * PCP (Priority Code Point) is a 3 bit field used for Ethernet level QoS.
687  */
688 #ifndef LWIP_VLAN_PCP
689 #define LWIP_VLAN_PCP                   0
690 #endif
691 
692 /** LWIP_ETHERNET==1: enable ethernet support even though ARP might be disabled
693  */
694 #if !defined LWIP_ETHERNET || defined __DOXYGEN__
695 #define LWIP_ETHERNET                   LWIP_ARP
696 #endif
697 
698 /** ETH_PAD_SIZE: number of bytes added before the ethernet header to ensure
699  * alignment of payload after that header. Since the header is 14 bytes long,
700  * without this padding e.g. addresses in the IP header will not be aligned
701  * on a 32-bit boundary, so setting this to 2 can speed up 32-bit-platforms.
702  */
703 #if !defined ETH_PAD_SIZE || defined __DOXYGEN__
704 #define ETH_PAD_SIZE                    0
705 #endif
706 
707 /** ETHARP_SUPPORT_STATIC_ENTRIES==1: enable code to support static ARP table
708  * entries (using etharp_add_static_entry/etharp_remove_static_entry).
709  */
710 #if !defined ETHARP_SUPPORT_STATIC_ENTRIES || defined __DOXYGEN__
711 #define ETHARP_SUPPORT_STATIC_ENTRIES   0
712 #endif
713 
714 /** ETHARP_TABLE_MATCH_NETIF==1: Match netif for ARP table entries.
715  * If disabled, duplicate IP address on multiple netifs are not supported
716  * (but this should only occur for AutoIP).
717  */
718 #if !defined ETHARP_TABLE_MATCH_NETIF || defined __DOXYGEN__
719 #define ETHARP_TABLE_MATCH_NETIF        !LWIP_SINGLE_NETIF
720 #endif
721 /**
722  * @}
723  */
724 
725 /*
726    --------------------------------
727    ---------- IP options ----------
728    --------------------------------
729 */
730 /**
731  * @defgroup lwip_opts_ipv4 IPv4
732  * @ingroup lwip_opts
733  * @{
734  */
735 /**
736  * LWIP_IPV4==1: Enable IPv4
737  */
738 #if !defined LWIP_IPV4 || defined __DOXYGEN__
739 #define LWIP_IPV4                       1
740 #endif
741 
742 /**
743  * IP_FORWARD==1: Enables the ability to forward IP packets across network
744  * interfaces. If you are going to run lwIP on a device with only one network
745  * interface, define this to 0.
746  */
747 #if !defined IP_FORWARD || defined __DOXYGEN__
748 #define IP_FORWARD                      0
749 #endif
750 
751 /**
752  * IP_REASSEMBLY==1: Reassemble incoming fragmented IP packets. Note that
753  * this option does not affect outgoing packet sizes, which can be controlled
754  * via IP_FRAG.
755  */
756 #if !defined IP_REASSEMBLY || defined __DOXYGEN__
757 #define IP_REASSEMBLY                   1
758 #endif
759 
760 /**
761  * IP_FRAG==1: Fragment outgoing IP packets if their size exceeds MTU. Note
762  * that this option does not affect incoming packet sizes, which can be
763  * controlled via IP_REASSEMBLY.
764  */
765 #if !defined IP_FRAG || defined __DOXYGEN__
766 #define IP_FRAG                         1
767 #endif
768 
769 #if !LWIP_IPV4
770 /* disable IPv4 extensions when IPv4 is disabled */
771 #undef IP_FORWARD
772 #define IP_FORWARD                      0
773 #undef IP_REASSEMBLY
774 #define IP_REASSEMBLY                   0
775 #undef IP_FRAG
776 #define IP_FRAG                         0
777 #endif /* !LWIP_IPV4 */
778 
779 /**
780  * IP_OPTIONS_ALLOWED: Defines the behavior for IP options.
781  *      IP_OPTIONS_ALLOWED==0: All packets with IP options are dropped.
782  *      IP_OPTIONS_ALLOWED==1: IP options are allowed (but not parsed).
783  */
784 #if !defined IP_OPTIONS_ALLOWED || defined __DOXYGEN__
785 #define IP_OPTIONS_ALLOWED              1
786 #endif
787 
788 /**
789  * IP_REASS_MAXAGE: Maximum time (in multiples of IP_TMR_INTERVAL - so seconds, normally)
790  * a fragmented IP packet waits for all fragments to arrive. If not all fragments arrived
791  * in this time, the whole packet is discarded.
792  */
793 #if !defined IP_REASS_MAXAGE || defined __DOXYGEN__
794 #define IP_REASS_MAXAGE                 15
795 #endif
796 
797 /**
798  * IP_REASS_MAX_PBUFS: Total maximum amount of pbufs waiting to be reassembled.
799  * Since the received pbufs are enqueued, be sure to configure
800  * PBUF_POOL_SIZE > IP_REASS_MAX_PBUFS so that the stack is still able to receive
801  * packets even if the maximum amount of fragments is enqueued for reassembly!
802  * When IPv4 *and* IPv6 are enabled, this even changes to
803  * (PBUF_POOL_SIZE > 2 * IP_REASS_MAX_PBUFS)!
804  */
805 #if !defined IP_REASS_MAX_PBUFS || defined __DOXYGEN__
806 #define IP_REASS_MAX_PBUFS              10
807 #endif
808 
809 /**
810  * IP_DEFAULT_TTL: Default value for Time-To-Live used by transport layers.
811  */
812 #if !defined IP_DEFAULT_TTL || defined __DOXYGEN__
813 #define IP_DEFAULT_TTL                  255
814 #endif
815 
816 /**
817  * IP_SOF_BROADCAST=1: Use the SOF_BROADCAST field to enable broadcast
818  * filter per pcb on udp and raw send operations. To enable broadcast filter
819  * on recv operations, you also have to set IP_SOF_BROADCAST_RECV=1.
820  */
821 #if !defined IP_SOF_BROADCAST || defined __DOXYGEN__
822 #define IP_SOF_BROADCAST                0
823 #endif
824 
825 /**
826  * IP_SOF_BROADCAST_RECV (requires IP_SOF_BROADCAST=1) enable the broadcast
827  * filter on recv operations.
828  */
829 #if !defined IP_SOF_BROADCAST_RECV || defined __DOXYGEN__
830 #define IP_SOF_BROADCAST_RECV           0
831 #endif
832 
833 /**
834  * IP_FORWARD_ALLOW_TX_ON_RX_NETIF==1: allow ip_forward() to send packets back
835  * out on the netif where it was received. This should only be used for
836  * wireless networks.
837  * ATTENTION: When this is 1, make sure your netif driver correctly marks incoming
838  * link-layer-broadcast/multicast packets as such using the corresponding pbuf flags!
839  */
840 #if !defined IP_FORWARD_ALLOW_TX_ON_RX_NETIF || defined __DOXYGEN__
841 #define IP_FORWARD_ALLOW_TX_ON_RX_NETIF 0
842 #endif
843 /**
844  * @}
845  */
846 
847 /*
848    ----------------------------------
849    ---------- ICMP options ----------
850    ----------------------------------
851 */
852 /**
853  * @defgroup lwip_opts_icmp ICMP
854  * @ingroup lwip_opts_ipv4
855  * @{
856  */
857 /**
858  * LWIP_ICMP==1: Enable ICMP module inside the IP stack.
859  * Be careful, disable that make your product non-compliant to RFC1122
860  */
861 #if !defined LWIP_ICMP || defined __DOXYGEN__
862 #define LWIP_ICMP                       1
863 #endif
864 
865 /**
866  * ICMP_TTL: Default value for Time-To-Live used by ICMP packets.
867  */
868 #if !defined ICMP_TTL || defined __DOXYGEN__
869 #define ICMP_TTL                        IP_DEFAULT_TTL
870 #endif
871 
872 /**
873  * LWIP_BROADCAST_PING==1: respond to broadcast pings (default is unicast only)
874  */
875 #if !defined LWIP_BROADCAST_PING || defined __DOXYGEN__
876 #define LWIP_BROADCAST_PING             0
877 #endif
878 
879 /**
880  * LWIP_MULTICAST_PING==1: respond to multicast pings (default is unicast only)
881  */
882 #if !defined LWIP_MULTICAST_PING || defined __DOXYGEN__
883 #define LWIP_MULTICAST_PING             0
884 #endif
885 /**
886  * @}
887  */
888 
889 /*
890    ---------------------------------
891    ---------- RAW options ----------
892    ---------------------------------
893 */
894 /**
895  * @defgroup lwip_opts_raw RAW
896  * @ingroup lwip_opts_callback
897  * @{
898  */
899 /**
900  * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
901  */
902 #if !defined LWIP_RAW || defined __DOXYGEN__
903 #define LWIP_RAW                        0
904 #endif
905 
906 /**
907  * LWIP_RAW==1: Enable application layer to hook into the IP layer itself.
908  */
909 #if !defined RAW_TTL || defined __DOXYGEN__
910 #define RAW_TTL                         IP_DEFAULT_TTL
911 #endif
912 /**
913  * @}
914  */
915 
916 /*
917    ----------------------------------
918    ---------- DHCP options ----------
919    ----------------------------------
920 */
921 /**
922  * @defgroup lwip_opts_dhcp DHCP
923  * @ingroup lwip_opts_ipv4
924  * @{
925  */
926 /**
927  * LWIP_DHCP==1: Enable DHCP module.
928  */
929 #if !defined LWIP_DHCP || defined __DOXYGEN__
930 #define LWIP_DHCP                       0
931 #endif
932 #if !LWIP_IPV4
933 /* disable DHCP when IPv4 is disabled */
934 #undef LWIP_DHCP
935 #define LWIP_DHCP                       0
936 #endif /* !LWIP_IPV4 */
937 
938 /**
939  * LWIP_DHCP_DOES_ACD_CHECK==1: Perform address conflict detection on the dhcp address.
940  */
941 #if !defined LWIP_DHCP_DOES_ACD_CHECK || defined __DOXYGEN__
942 #define LWIP_DHCP_DOES_ACD_CHECK        LWIP_DHCP
943 #endif
944 
945 /**
946  * LWIP_DHCP_BOOTP_FILE==1: Store offered_si_addr and boot_file_name.
947  */
948 #if !defined LWIP_DHCP_BOOTP_FILE || defined __DOXYGEN__
949 #define LWIP_DHCP_BOOTP_FILE            0
950 #endif
951 
952 /**
953  * LWIP_DHCP_GETS_NTP==1: Request NTP servers with discover/select. For each
954  * response packet, an callback is called, which has to be provided by the port:
955  * void dhcp_set_ntp_servers(u8_t num_ntp_servers, ip_addr_t* ntp_server_addrs);
956 */
957 #if !defined LWIP_DHCP_GET_NTP_SRV || defined __DOXYGEN__
958 #define LWIP_DHCP_GET_NTP_SRV           0
959 #endif
960 
961 /**
962  * The maximum of NTP servers requested
963  */
964 #if !defined LWIP_DHCP_MAX_NTP_SERVERS || defined __DOXYGEN__
965 #define LWIP_DHCP_MAX_NTP_SERVERS       1
966 #endif
967 
968 /**
969  * LWIP_DHCP_MAX_DNS_SERVERS > 0: Request DNS servers with discover/select.
970  * DNS servers received in the response are passed to DNS via @ref dns_setserver()
971  * (up to the maximum limit defined here).
972  */
973 #if !defined LWIP_DHCP_MAX_DNS_SERVERS || defined __DOXYGEN__
974 #define LWIP_DHCP_MAX_DNS_SERVERS       DNS_MAX_SERVERS
975 #endif
976 /**
977  * @}
978  */
979 
980 /*
981    ------------------------------------
982    ---------- AUTOIP options ----------
983    ------------------------------------
984 */
985 /**
986  * @defgroup lwip_opts_autoip AUTOIP
987  * @ingroup lwip_opts_ipv4
988  * @{
989  */
990 /**
991  * LWIP_AUTOIP==1: Enable AUTOIP module.
992  */
993 #if !defined LWIP_AUTOIP || defined __DOXYGEN__
994 #define LWIP_AUTOIP                     0
995 #endif
996 #if !LWIP_IPV4
997 /* disable AUTOIP when IPv4 is disabled */
998 #undef LWIP_AUTOIP
999 #define LWIP_AUTOIP                     0
1000 #endif /* !LWIP_IPV4 */
1001 
1002 /**
1003  * LWIP_DHCP_AUTOIP_COOP==1: Allow DHCP and AUTOIP to be both enabled on
1004  * the same interface at the same time.
1005  */
1006 #if !defined LWIP_DHCP_AUTOIP_COOP || defined __DOXYGEN__
1007 #define LWIP_DHCP_AUTOIP_COOP           0
1008 #endif
1009 
1010 /**
1011  * LWIP_DHCP_AUTOIP_COOP_TRIES: Set to the number of DHCP DISCOVER probes
1012  * that should be sent before falling back on AUTOIP (the DHCP client keeps
1013  * running in this case). This can be set as low as 1 to get an AutoIP address
1014  * very  quickly, but you should be prepared to handle a changing IP address
1015  * when DHCP overrides AutoIP.
1016  */
1017 #if !defined LWIP_DHCP_AUTOIP_COOP_TRIES || defined __DOXYGEN__
1018 #define LWIP_DHCP_AUTOIP_COOP_TRIES     9
1019 #endif
1020 /**
1021  * @}
1022  */
1023 
1024 /*
1025    ------------------------------------
1026    ----------- ACD options ------------
1027    ------------------------------------
1028 */
1029 /**
1030  * @defgroup lwip_opts_acd ACD
1031  * @ingroup lwip_opts_ipv4
1032  * @{
1033  */
1034  /**
1035   * LWIP_ACD==1: Enable ACD module. ACD module is needed when using AUTOIP.
1036   */
1037 #if !defined LWIP_ACD || defined __DOXYGEN__
1038 #define LWIP_ACD                     (LWIP_AUTOIP || LWIP_DHCP_DOES_ACD_CHECK)
1039 #endif
1040 #if !LWIP_IPV4
1041 /* disable ACD when IPv4 is disabled */
1042 #undef LWIP_ACD
1043 #define LWIP_ACD                     0
1044 #endif /* !LWIP_IPV4 */
1045 /**
1046  * @}
1047  */
1048 
1049 /*
1050    ----------------------------------
1051    ----- SNMP MIB2 support      -----
1052    ----------------------------------
1053 */
1054 /**
1055  * @defgroup lwip_opts_mib2 SNMP MIB2 callbacks
1056  * @ingroup lwip_opts_infrastructure
1057  * @{
1058  */
1059 /**
1060  * LWIP_MIB2_CALLBACKS==1: Turn on SNMP MIB2 callbacks.
1061  * Turn this on to get callbacks needed to implement MIB2.
1062  * Usually MIB2_STATS should be enabled, too.
1063  */
1064 #if !defined LWIP_MIB2_CALLBACKS || defined __DOXYGEN__
1065 #define LWIP_MIB2_CALLBACKS             0
1066 #endif
1067 /**
1068  * @}
1069  */
1070 
1071 /*
1072    ----------------------------------
1073    -------- Multicast options -------
1074    ----------------------------------
1075 */
1076 /**
1077  * @defgroup lwip_opts_multicast Multicast
1078  * @ingroup lwip_opts_infrastructure
1079  * @{
1080  */
1081 /**
1082  * LWIP_MULTICAST_TX_OPTIONS==1: Enable multicast TX support like the socket options
1083  * IP_MULTICAST_TTL/IP_MULTICAST_IF/IP_MULTICAST_LOOP, as well as (currently only)
1084  * core support for the corresponding IPv6 options.
1085  */
1086 #if !defined LWIP_MULTICAST_TX_OPTIONS || defined __DOXYGEN__
1087 #define LWIP_MULTICAST_TX_OPTIONS       ((LWIP_IGMP || LWIP_IPV6_MLD) && (LWIP_UDP || LWIP_RAW))
1088 #endif
1089 /**
1090  * @}
1091  */
1092 
1093 /*
1094    ----------------------------------
1095    ---------- IGMP options ----------
1096    ----------------------------------
1097 */
1098 /**
1099  * @defgroup lwip_opts_igmp IGMP
1100  * @ingroup lwip_opts_ipv4
1101  * @{
1102  */
1103 /**
1104  * LWIP_IGMP==1: Turn on IGMP module.
1105  */
1106 #if !defined LWIP_IGMP || defined __DOXYGEN__
1107 #define LWIP_IGMP                       0
1108 #endif
1109 #if !LWIP_IPV4
1110 #undef LWIP_IGMP
1111 #define LWIP_IGMP                       0
1112 #endif
1113 /**
1114  * @}
1115  */
1116 
1117 /*
1118    ----------------------------------
1119    ---------- DNS options -----------
1120    ----------------------------------
1121 */
1122 /**
1123  * @defgroup lwip_opts_dns DNS
1124  * @ingroup lwip_opts_callback
1125  * @{
1126  */
1127 /**
1128  * LWIP_DNS==1: Turn on DNS module. UDP must be available for DNS
1129  * transport.
1130  */
1131 #if !defined LWIP_DNS || defined __DOXYGEN__
1132 #define LWIP_DNS                        0
1133 #endif
1134 
1135 /** DNS maximum number of entries to maintain locally. */
1136 #if !defined DNS_TABLE_SIZE || defined __DOXYGEN__
1137 #define DNS_TABLE_SIZE                  4
1138 #endif
1139 
1140 /** DNS maximum host name length supported in the name table. */
1141 #if !defined DNS_MAX_NAME_LENGTH || defined __DOXYGEN__
1142 #define DNS_MAX_NAME_LENGTH             256
1143 #endif
1144 
1145 /** The maximum of DNS servers
1146  * The first server can be initialized automatically by defining
1147  * DNS_SERVER_ADDRESS(ipaddr), where 'ipaddr' is an 'ip_addr_t*'
1148  */
1149 #if !defined DNS_MAX_SERVERS || defined __DOXYGEN__
1150 #define DNS_MAX_SERVERS                 2
1151 #endif
1152 
1153 /** DNS maximum number of retries when asking for a name, before "timeout". */
1154 #if !defined DNS_MAX_RETRIES || defined __DOXYGEN__
1155 #define DNS_MAX_RETRIES                 4
1156 #endif
1157 
1158 /** DNS do a name checking between the query and the response. */
1159 #if !defined DNS_DOES_NAME_CHECK || defined __DOXYGEN__
1160 #define DNS_DOES_NAME_CHECK             1
1161 #endif
1162 
1163 /** LWIP_DNS_SECURE: controls the security level of the DNS implementation
1164  * Use all DNS security features by default.
1165  * This is overridable but should only be needed by very small targets
1166  * or when using against non standard DNS servers. */
1167 #if !defined LWIP_DNS_SECURE || defined __DOXYGEN__
1168 #define LWIP_DNS_SECURE (LWIP_DNS_SECURE_RAND_XID | LWIP_DNS_SECURE_NO_MULTIPLE_OUTSTANDING | LWIP_DNS_SECURE_RAND_SRC_PORT)
1169 #endif
1170 
1171 /* A list of DNS security features follows */
1172 #define LWIP_DNS_SECURE_RAND_XID                1
1173 #define LWIP_DNS_SECURE_NO_MULTIPLE_OUTSTANDING 2
1174 #define LWIP_DNS_SECURE_RAND_SRC_PORT           4
1175 
1176 /** DNS_LOCAL_HOSTLIST: Implements a local host-to-address list. If enabled, you have to define an initializer:
1177  *  \#define DNS_LOCAL_HOSTLIST_INIT {DNS_LOCAL_HOSTLIST_ELEM("host_ip4", IPADDR4_INIT_BYTES(1,2,3,4)), \
1178  *                                    DNS_LOCAL_HOSTLIST_ELEM("host_ip6", IPADDR6_INIT_HOST(123, 234, 345, 456)}
1179  *
1180  *  Instead, you can also use an external function:
1181  *  \#define DNS_LOOKUP_LOCAL_EXTERN(name, namelen, addr, dns_addrtype) my_lookup_function(name, namelen, addr, dns_addrtype)
1182  *  with function signature:
1183  *  extern err_t my_lookup_function(const char *name, size_t namelen, ip_addr_t *addr, u8_t dns_addrtype)
1184  *  that looks up the IP address and returns ERR_OK if found (LWIP_DNS_ADDRTYPE_xxx is passed in dns_addrtype).
1185  */
1186 #if !defined DNS_LOCAL_HOSTLIST || defined __DOXYGEN__
1187 #define DNS_LOCAL_HOSTLIST              0
1188 #endif /* DNS_LOCAL_HOSTLIST */
1189 
1190 /** If this is turned on, the local host-list can be dynamically changed
1191  *  at runtime. */
1192 #if !defined DNS_LOCAL_HOSTLIST_IS_DYNAMIC || defined __DOXYGEN__
1193 #define DNS_LOCAL_HOSTLIST_IS_DYNAMIC   0
1194 #endif /* DNS_LOCAL_HOSTLIST_IS_DYNAMIC */
1195 
1196 /** Set this to 1 to enable querying ".local" names via mDNS
1197  *  using a One-Shot Multicast DNS Query */
1198 #if !defined LWIP_DNS_SUPPORT_MDNS_QUERIES || defined __DOXYGEN__
1199 #define LWIP_DNS_SUPPORT_MDNS_QUERIES   0
1200 #endif
1201 /**
1202  * @}
1203  */
1204 
1205 /*
1206    ---------------------------------
1207    ---------- UDP options ----------
1208    ---------------------------------
1209 */
1210 /**
1211  * @defgroup lwip_opts_udp UDP
1212  * @ingroup lwip_opts_callback
1213  * @{
1214  */
1215 /**
1216  * LWIP_UDP==1: Turn on UDP.
1217  */
1218 #if !defined LWIP_UDP || defined __DOXYGEN__
1219 #define LWIP_UDP                        1
1220 #endif
1221 
1222 /**
1223  * LWIP_UDPLITE==1: Turn on UDP-Lite. (Requires LWIP_UDP)
1224  */
1225 #if !defined LWIP_UDPLITE || defined __DOXYGEN__
1226 #define LWIP_UDPLITE                    0
1227 #endif
1228 
1229 /**
1230  * UDP_TTL: Default Time-To-Live value.
1231  */
1232 #if !defined UDP_TTL || defined __DOXYGEN__
1233 #define UDP_TTL                         IP_DEFAULT_TTL
1234 #endif
1235 
1236 /**
1237  * LWIP_NETBUF_RECVINFO==1: append destination addr and port to every netbuf.
1238  */
1239 #if !defined LWIP_NETBUF_RECVINFO || defined __DOXYGEN__
1240 #define LWIP_NETBUF_RECVINFO            0
1241 #endif
1242 /**
1243  * @}
1244  */
1245 
1246 /*
1247    ---------------------------------
1248    ---------- TCP options ----------
1249    ---------------------------------
1250 */
1251 /**
1252  * @defgroup lwip_opts_tcp TCP
1253  * @ingroup lwip_opts_callback
1254  * @{
1255  */
1256 /**
1257  * LWIP_TCP==1: Turn on TCP.
1258  */
1259 #if !defined LWIP_TCP || defined __DOXYGEN__
1260 #define LWIP_TCP                        1
1261 #endif
1262 
1263 /**
1264  * TCP_TTL: Default Time-To-Live value.
1265  */
1266 #if !defined TCP_TTL || defined __DOXYGEN__
1267 #define TCP_TTL                         IP_DEFAULT_TTL
1268 #endif
1269 
1270 /**
1271  * TCP_WND: The size of a TCP window.  This must be at least
1272  * (2 * TCP_MSS) for things to work well.
1273  * ATTENTION: when using TCP_RCV_SCALE, TCP_WND is the total size
1274  * with scaling applied. Maximum window value in the TCP header
1275  * will be TCP_WND >> TCP_RCV_SCALE
1276  */
1277 #if !defined TCP_WND || defined __DOXYGEN__
1278 #define TCP_WND                         (4 * TCP_MSS)
1279 #endif
1280 
1281 /**
1282  * TCP_MAXRTX: Maximum number of retransmissions of data segments.
1283  */
1284 #if !defined TCP_MAXRTX || defined __DOXYGEN__
1285 #define TCP_MAXRTX                      12
1286 #endif
1287 
1288 /**
1289  * TCP_SYNMAXRTX: Maximum number of retransmissions of SYN segments.
1290  */
1291 #if !defined TCP_SYNMAXRTX || defined __DOXYGEN__
1292 #define TCP_SYNMAXRTX                   6
1293 #endif
1294 
1295 /**
1296  * TCP_QUEUE_OOSEQ==1: TCP will queue segments that arrive out of order.
1297  * Define to 0 if your device is low on memory.
1298  */
1299 #if !defined TCP_QUEUE_OOSEQ || defined __DOXYGEN__
1300 #define TCP_QUEUE_OOSEQ                 LWIP_TCP
1301 #endif
1302 
1303 /**
1304  * LWIP_TCP_SACK_OUT==1: TCP will support sending selective acknowledgements (SACKs).
1305  */
1306 #if !defined LWIP_TCP_SACK_OUT || defined __DOXYGEN__
1307 #define LWIP_TCP_SACK_OUT               0
1308 #endif
1309 
1310 /**
1311  * LWIP_TCP_MAX_SACK_NUM: The maximum number of SACK values to include in TCP segments.
1312  * Must be at least 1, but is only used if LWIP_TCP_SACK_OUT is enabled.
1313  * NOTE: Even though we never send more than 3 or 4 SACK ranges in a single segment
1314  * (depending on other options), setting this option to values greater than 4 is not pointless.
1315  * This is basically the max number of SACK ranges we want to keep track of.
1316  * As new data is delivered, some of the SACK ranges may be removed or merged.
1317  * In that case some of those older SACK ranges may be used again.
1318  * The amount of memory used to store SACK ranges is LWIP_TCP_MAX_SACK_NUM * 8 bytes for each TCP PCB.
1319  */
1320 #if !defined LWIP_TCP_MAX_SACK_NUM || defined __DOXYGEN__
1321 #define LWIP_TCP_MAX_SACK_NUM           4
1322 #endif
1323 
1324 /**
1325  * TCP_MSS: TCP Maximum segment size. (default is 536, a conservative default,
1326  * you might want to increase this.)
1327  * For the receive side, this MSS is advertised to the remote side
1328  * when opening a connection. For the transmit size, this MSS sets
1329  * an upper limit on the MSS advertised by the remote host.
1330  */
1331 #if !defined TCP_MSS || defined __DOXYGEN__
1332 #define TCP_MSS                         536
1333 #endif
1334 
1335 /**
1336  * TCP_CALCULATE_EFF_SEND_MSS: "The maximum size of a segment that TCP really
1337  * sends, the 'effective send MSS,' MUST be the smaller of the send MSS (which
1338  * reflects the available reassembly buffer size at the remote host) and the
1339  * largest size permitted by the IP layer" (RFC 1122)
1340  * Setting this to 1 enables code that checks TCP_MSS against the MTU of the
1341  * netif used for a connection and limits the MSS if it would be too big otherwise.
1342  */
1343 #if !defined TCP_CALCULATE_EFF_SEND_MSS || defined __DOXYGEN__
1344 #define TCP_CALCULATE_EFF_SEND_MSS      1
1345 #endif
1346 
1347 
1348 /**
1349  * TCP_SND_BUF: TCP sender buffer space (bytes).
1350  * To achieve good performance, this should be at least 2 * TCP_MSS.
1351  */
1352 #if !defined TCP_SND_BUF || defined __DOXYGEN__
1353 #define TCP_SND_BUF                     (2 * TCP_MSS)
1354 #endif
1355 
1356 /**
1357  * TCP_SND_QUEUELEN: TCP sender buffer space (pbufs). This must be at least
1358  * as much as (2 * TCP_SND_BUF/TCP_MSS) for things to work.
1359  */
1360 #if !defined TCP_SND_QUEUELEN || defined __DOXYGEN__
1361 #define TCP_SND_QUEUELEN                ((4 * (TCP_SND_BUF) + (TCP_MSS - 1))/(TCP_MSS))
1362 #endif
1363 
1364 /**
1365  * TCP_SNDLOWAT: TCP writable space (bytes). This must be less than
1366  * TCP_SND_BUF. It is the amount of space which must be available in the
1367  * TCP snd_buf for select to return writable (combined with TCP_SNDQUEUELOWAT).
1368  */
1369 #if !defined TCP_SNDLOWAT || defined __DOXYGEN__
1370 #define TCP_SNDLOWAT                    LWIP_MIN(LWIP_MAX(((TCP_SND_BUF)/2), (2 * TCP_MSS) + 1), (TCP_SND_BUF) - 1)
1371 #endif
1372 
1373 /**
1374  * TCP_SNDQUEUELOWAT: TCP writable bufs (pbuf count). This must be less
1375  * than TCP_SND_QUEUELEN. If the number of pbufs queued on a pcb drops below
1376  * this number, select returns writable (combined with TCP_SNDLOWAT).
1377  */
1378 #if !defined TCP_SNDQUEUELOWAT || defined __DOXYGEN__
1379 #define TCP_SNDQUEUELOWAT               LWIP_MAX(((TCP_SND_QUEUELEN)/2), 5)
1380 #endif
1381 
1382 /**
1383  * TCP_OOSEQ_MAX_BYTES: The default maximum number of bytes queued on ooseq per
1384  * pcb if TCP_OOSEQ_BYTES_LIMIT is not defined. Default is 0 (no limit).
1385  * Only valid for TCP_QUEUE_OOSEQ==1.
1386  */
1387 #if !defined TCP_OOSEQ_MAX_BYTES || defined __DOXYGEN__
1388 #define TCP_OOSEQ_MAX_BYTES             0
1389 #endif
1390 
1391 /**
1392  * TCP_OOSEQ_BYTES_LIMIT(pcb): Return the maximum number of bytes to be queued
1393  * on ooseq per pcb, given the pcb. Only valid for TCP_QUEUE_OOSEQ==1 &&
1394  * TCP_OOSEQ_MAX_BYTES==1.
1395  * Use this to override TCP_OOSEQ_MAX_BYTES to a dynamic value per pcb.
1396  */
1397 #if !defined TCP_OOSEQ_BYTES_LIMIT
1398 #if TCP_OOSEQ_MAX_BYTES
1399 #define TCP_OOSEQ_BYTES_LIMIT(pcb)      TCP_OOSEQ_MAX_BYTES
1400 #elif defined __DOXYGEN__
1401 #define TCP_OOSEQ_BYTES_LIMIT(pcb)
1402 #endif
1403 #endif
1404 
1405 /**
1406  * TCP_OOSEQ_MAX_PBUFS: The default maximum number of pbufs queued on ooseq per
1407  * pcb if TCP_OOSEQ_BYTES_LIMIT is not defined. Default is 0 (no limit).
1408  * Only valid for TCP_QUEUE_OOSEQ==1.
1409  */
1410 #if !defined TCP_OOSEQ_MAX_PBUFS || defined __DOXYGEN__
1411 #define TCP_OOSEQ_MAX_PBUFS             0
1412 #endif
1413 
1414 /**
1415  * TCP_OOSEQ_PBUFS_LIMIT(pcb): Return the maximum number of pbufs to be queued
1416  * on ooseq per pcb, given the pcb.  Only valid for TCP_QUEUE_OOSEQ==1 &&
1417  * TCP_OOSEQ_MAX_PBUFS==1.
1418  * Use this to override TCP_OOSEQ_MAX_PBUFS to a dynamic value per pcb.
1419  */
1420 #if !defined TCP_OOSEQ_PBUFS_LIMIT
1421 #if TCP_OOSEQ_MAX_PBUFS
1422 #define TCP_OOSEQ_PBUFS_LIMIT(pcb)      TCP_OOSEQ_MAX_PBUFS
1423 #elif defined __DOXYGEN__
1424 #define TCP_OOSEQ_PBUFS_LIMIT(pcb)
1425 #endif
1426 #endif
1427 
1428 /**
1429  * TCP_LISTEN_BACKLOG: Enable the backlog option for tcp listen pcb.
1430  */
1431 #if !defined TCP_LISTEN_BACKLOG || defined __DOXYGEN__
1432 #define TCP_LISTEN_BACKLOG              0
1433 #endif
1434 
1435 /**
1436  * The maximum allowed backlog for TCP listen netconns.
1437  * This backlog is used unless another is explicitly specified.
1438  * 0xff is the maximum (u8_t).
1439  */
1440 #if !defined TCP_DEFAULT_LISTEN_BACKLOG || defined __DOXYGEN__
1441 #define TCP_DEFAULT_LISTEN_BACKLOG      0xff
1442 #endif
1443 
1444 /**
1445  * TCP_OVERSIZE: The maximum number of bytes that tcp_write may
1446  * allocate ahead of time in an attempt to create shorter pbuf chains
1447  * for transmission. The meaningful range is 0 to TCP_MSS. Some
1448  * suggested values are:
1449  *
1450  * 0:         Disable oversized allocation. Each tcp_write() allocates a new
1451               pbuf (old behaviour).
1452  * 1:         Allocate size-aligned pbufs with minimal excess. Use this if your
1453  *            scatter-gather DMA requires aligned fragments.
1454  * 128:       Limit the pbuf/memory overhead to 20%.
1455  * TCP_MSS:   Try to create unfragmented TCP packets.
1456  * TCP_MSS/4: Try to create 4 fragments or less per TCP packet.
1457  */
1458 #if !defined TCP_OVERSIZE || defined __DOXYGEN__
1459 #define TCP_OVERSIZE                    TCP_MSS
1460 #endif
1461 
1462 /**
1463  * LWIP_TCP_TIMESTAMPS==1: support the TCP timestamp option.
1464  * The timestamp option is currently only used to help remote hosts, it is not
1465  * really used locally. Therefore, it is only enabled when a TS option is
1466  * received in the initial SYN packet from a remote host.
1467  */
1468 #if !defined LWIP_TCP_TIMESTAMPS || defined __DOXYGEN__
1469 #define LWIP_TCP_TIMESTAMPS             0
1470 #endif
1471 
1472 /**
1473  * TCP_WND_UPDATE_THRESHOLD: difference in window to trigger an
1474  * explicit window update
1475  */
1476 #if !defined TCP_WND_UPDATE_THRESHOLD || defined __DOXYGEN__
1477 #define TCP_WND_UPDATE_THRESHOLD        LWIP_MIN((TCP_WND / 4), (TCP_MSS * 4))
1478 #endif
1479 
1480 /**
1481  * LWIP_EVENT_API and LWIP_CALLBACK_API: Only one of these should be set to 1.
1482  *     LWIP_EVENT_API==1: The user defines lwip_tcp_event() to receive all
1483  *         events (accept, sent, etc) that happen in the system.
1484  *     LWIP_CALLBACK_API==1: The PCB callback function is called directly
1485  *         for the event. This is the default.
1486  */
1487 #if !defined(LWIP_EVENT_API) && !defined(LWIP_CALLBACK_API) || defined __DOXYGEN__
1488 #define LWIP_EVENT_API                  0
1489 #define LWIP_CALLBACK_API               1
1490 #else
1491 #ifndef LWIP_EVENT_API
1492 #define LWIP_EVENT_API                  0
1493 #endif
1494 #ifndef LWIP_CALLBACK_API
1495 #define LWIP_CALLBACK_API               0
1496 #endif
1497 #endif
1498 
1499 /**
1500  * LWIP_WND_SCALE and TCP_RCV_SCALE:
1501  * Set LWIP_WND_SCALE to 1 to enable window scaling.
1502  * Set TCP_RCV_SCALE to the desired scaling factor (shift count in the
1503  * range of [0..14]).
1504  * When LWIP_WND_SCALE is enabled but TCP_RCV_SCALE is 0, we can use a large
1505  * send window while having a small receive window only.
1506  */
1507 #if !defined LWIP_WND_SCALE || defined __DOXYGEN__
1508 #define LWIP_WND_SCALE                  0
1509 #define TCP_RCV_SCALE                   0
1510 #endif
1511 
1512 /**
1513  * LWIP_TCP_PCB_NUM_EXT_ARGS:
1514  * When this is > 0, every tcp pcb (including listen pcb) includes a number of
1515  * additional argument entries in an array (see tcp_ext_arg_alloc_id)
1516  */
1517 #if !defined LWIP_TCP_PCB_NUM_EXT_ARGS || defined __DOXYGEN__
1518 #define LWIP_TCP_PCB_NUM_EXT_ARGS       0
1519 #endif
1520 
1521 /** LWIP_ALTCP==1: enable the altcp API.
1522  * altcp is an abstraction layer that prevents applications linking against the
1523  * tcp.h functions but provides the same functionality. It is used to e.g. add
1524  * SSL/TLS or proxy-connect support to an application written for the tcp callback
1525  * API without that application knowing the protocol details.
1526  *
1527  * With LWIP_ALTCP==0, applications written against the altcp API can still be
1528  * compiled but are directly linked against the tcp.h callback API and then
1529  * cannot use layered protocols.
1530  *
1531  * See @ref altcp_api
1532  */
1533 #if !defined LWIP_ALTCP || defined __DOXYGEN__
1534 #define LWIP_ALTCP                      0
1535 #endif
1536 
1537 /** LWIP_ALTCP_TLS==1: enable TLS support for altcp API.
1538  * This needs a port of the functions in altcp_tls.h to a TLS library.
1539  * A port to ARM mbedtls is provided with lwIP, see apps/altcp_tls/ directory
1540  * and LWIP_ALTCP_TLS_MBEDTLS option.
1541  */
1542 #if !defined LWIP_ALTCP_TLS || defined __DOXYGEN__
1543 #define LWIP_ALTCP_TLS                  0
1544 #endif
1545 
1546 /**
1547  * @}
1548  */
1549 
1550 /*
1551    ----------------------------------
1552    ---------- Pbuf options ----------
1553    ----------------------------------
1554 */
1555 /**
1556  * @defgroup lwip_opts_pbuf PBUF
1557  * @ingroup lwip_opts
1558  * @{
1559  */
1560 /**
1561  * PBUF_LINK_HLEN: the number of bytes that should be allocated for a
1562  * link level header. The default is 14, the standard value for
1563  * Ethernet.
1564  */
1565  #if !defined PBUF_LINK_HLEN || defined __DOXYGEN__
1566 #if (defined LWIP_HOOK_VLAN_SET || LWIP_VLAN_PCP) && !defined __DOXYGEN__
1567  #define PBUF_LINK_HLEN                  (18 + ETH_PAD_SIZE)
1568 #else /* LWIP_HOOK_VLAN_SET || LWIP_VLAN_PCP */
1569  #define PBUF_LINK_HLEN                  (14 + ETH_PAD_SIZE)
1570 #endif /* LWIP_HOOK_VLAN_SET || LWIP_VLAN_PCP */
1571  #endif
1572 
1573 /**
1574  * PBUF_LINK_ENCAPSULATION_HLEN: the number of bytes that should be allocated
1575  * for an additional encapsulation header before ethernet headers (e.g. 802.11)
1576  */
1577 #if !defined PBUF_LINK_ENCAPSULATION_HLEN || defined __DOXYGEN__
1578 #define PBUF_LINK_ENCAPSULATION_HLEN    0
1579 #endif
1580 
1581 /**
1582  * PBUF_POOL_BUFSIZE: the size of each pbuf in the pbuf pool. The default is
1583  * designed to accommodate single full size TCP frame in one pbuf, including
1584  * TCP_MSS, IP header, and link header.
1585  */
1586 #if !defined PBUF_POOL_BUFSIZE || defined __DOXYGEN__
1587 #define PBUF_POOL_BUFSIZE               LWIP_MEM_ALIGN_SIZE(TCP_MSS+40+PBUF_LINK_ENCAPSULATION_HLEN+PBUF_LINK_HLEN)
1588 #endif
1589 
1590 /**
1591  * LWIP_PBUF_REF_T: Refcount type in pbuf.
1592  * Default width of u8_t can be increased if 255 refs are not enough for you.
1593  */
1594 #if !defined LWIP_PBUF_REF_T || defined __DOXYGEN__
1595 #define LWIP_PBUF_REF_T                 u8_t
1596 #endif
1597 
1598 /**
1599  * LWIP_PBUF_CUSTOM_DATA: Store private data on pbufs (e.g. timestamps)
1600  * This extends struct pbuf so user can store custom data on every pbuf.
1601  */
1602 #if !defined LWIP_PBUF_CUSTOM_DATA || defined __DOXYGEN__
1603 #define LWIP_PBUF_CUSTOM_DATA
1604 #endif
1605 /**
1606  * @}
1607  */
1608 
1609 /*
1610    ------------------------------------------------
1611    ---------- Network Interfaces options ----------
1612    ------------------------------------------------
1613 */
1614 /**
1615  * @defgroup lwip_opts_netif NETIF
1616  * @ingroup lwip_opts
1617  * @{
1618  */
1619 /**
1620  * LWIP_SINGLE_NETIF==1: use a single netif only. This is the common case for
1621  * small real-life targets. Some code like routing etc. can be left out.
1622  */
1623 #if !defined LWIP_SINGLE_NETIF || defined __DOXYGEN__
1624 #define LWIP_SINGLE_NETIF               0
1625 #endif
1626 
1627 /**
1628  * LWIP_NETIF_HOSTNAME==1: use DHCP_OPTION_HOSTNAME with netif's hostname
1629  * field.
1630  */
1631 #if !defined LWIP_NETIF_HOSTNAME || defined __DOXYGEN__
1632 #define LWIP_NETIF_HOSTNAME             0
1633 #endif
1634 
1635 /**
1636  * LWIP_NETIF_API==1: Support netif api (in netifapi.c)
1637  */
1638 #if !defined LWIP_NETIF_API || defined __DOXYGEN__
1639 #define LWIP_NETIF_API                  0
1640 #endif
1641 
1642 /**
1643  * LWIP_NETIF_STATUS_CALLBACK==1: Support a callback function whenever an interface
1644  * changes its up/down status (i.e., due to DHCP IP acquisition)
1645  */
1646 #if !defined LWIP_NETIF_STATUS_CALLBACK || defined __DOXYGEN__
1647 #define LWIP_NETIF_STATUS_CALLBACK      0
1648 #endif
1649 
1650 /**
1651  * LWIP_NETIF_EXT_STATUS_CALLBACK==1: Support an extended callback function
1652  * for several netif related event that supports multiple subscribers.
1653  * @see netif_ext_status_callback
1654  */
1655 #if !defined LWIP_NETIF_EXT_STATUS_CALLBACK || defined __DOXYGEN__
1656 #define LWIP_NETIF_EXT_STATUS_CALLBACK  0
1657 #endif
1658 
1659 /**
1660  * LWIP_NETIF_LINK_CALLBACK==1: Support a callback function from an interface
1661  * whenever the link changes (i.e., link down)
1662  */
1663 #if !defined LWIP_NETIF_LINK_CALLBACK || defined __DOXYGEN__
1664 #define LWIP_NETIF_LINK_CALLBACK        0
1665 #endif
1666 
1667 /**
1668  * LWIP_NETIF_REMOVE_CALLBACK==1: Support a callback function that is called
1669  * when a netif has been removed
1670  */
1671 #if !defined LWIP_NETIF_REMOVE_CALLBACK || defined __DOXYGEN__
1672 #define LWIP_NETIF_REMOVE_CALLBACK      0
1673 #endif
1674 
1675 /**
1676  * LWIP_NETIF_HWADDRHINT==1: Cache link-layer-address hints (e.g. table
1677  * indices) in struct netif. TCP and UDP can make use of this to prevent
1678  * scanning the ARP table for every sent packet. While this is faster for big
1679  * ARP tables or many concurrent connections, it might be counterproductive
1680  * if you have a tiny ARP table or if there never are concurrent connections.
1681  */
1682 #if !defined LWIP_NETIF_HWADDRHINT || defined __DOXYGEN__
1683 #define LWIP_NETIF_HWADDRHINT           0
1684 #endif
1685 
1686 /**
1687  * LWIP_NETIF_TX_SINGLE_PBUF: if this is set to 1, lwIP *tries* to put all data
1688  * to be sent into one single pbuf. This is for compatibility with DMA-enabled
1689  * MACs that do not support scatter-gather.
1690  * Beware that this might involve CPU-memcpy before transmitting that would not
1691  * be needed without this flag! Use this only if you need to!
1692  *
1693  * ATTENTION: a driver should *NOT* rely on getting single pbufs but check TX
1694  * pbufs for being in one piece. If not, @ref pbuf_clone can be used to get
1695  * a single pbuf:
1696  *   if (p->next != NULL) {
1697  *     struct pbuf *q = pbuf_clone(PBUF_RAW, PBUF_RAM, p);
1698  *     if (q == NULL) {
1699  *       return ERR_MEM;
1700  *     }
1701  *     p = q; ATTENTION: do NOT free the old 'p' as the ref belongs to the caller!
1702  *   }
1703  */
1704 #if !defined LWIP_NETIF_TX_SINGLE_PBUF || defined __DOXYGEN__
1705 #define LWIP_NETIF_TX_SINGLE_PBUF       0
1706 #endif /* LWIP_NETIF_TX_SINGLE_PBUF */
1707 
1708 /**
1709  * LWIP_NUM_NETIF_CLIENT_DATA: Number of clients that may store
1710  * data in client_data member array of struct netif (max. 256).
1711  */
1712 #if !defined LWIP_NUM_NETIF_CLIENT_DATA || defined __DOXYGEN__
1713 #define LWIP_NUM_NETIF_CLIENT_DATA      0
1714 #endif
1715 /**
1716  * @}
1717  */
1718 
1719 /*
1720    ------------------------------------
1721    ---------- LOOPIF options ----------
1722    ------------------------------------
1723 */
1724 /**
1725  * @defgroup lwip_opts_loop Loopback interface
1726  * @ingroup lwip_opts_netif
1727  * @{
1728  */
1729 /**
1730  * LWIP_HAVE_LOOPIF==1: Support loop interface (127.0.0.1).
1731  * This is only needed when no real netifs are available. If at least one other
1732  * netif is available, loopback traffic uses this netif.
1733  */
1734 #if !defined LWIP_HAVE_LOOPIF || defined __DOXYGEN__
1735 #define LWIP_HAVE_LOOPIF                (LWIP_NETIF_LOOPBACK && !LWIP_SINGLE_NETIF)
1736 #endif
1737 
1738 /**
1739  * LWIP_LOOPIF_MULTICAST==1: Support multicast/IGMP on loop interface (127.0.0.1).
1740  */
1741 #if !defined LWIP_LOOPIF_MULTICAST || defined __DOXYGEN__
1742 #define LWIP_LOOPIF_MULTICAST           0
1743 #endif
1744 
1745 /**
1746  * LWIP_NETIF_LOOPBACK==1: Support sending packets with a destination IP
1747  * address equal to the netif IP address, looping them back up the stack.
1748  */
1749 #if !defined LWIP_NETIF_LOOPBACK || defined __DOXYGEN__
1750 #define LWIP_NETIF_LOOPBACK             0
1751 #endif
1752 
1753 /**
1754  * LWIP_LOOPBACK_MAX_PBUFS: Maximum number of pbufs on queue for loopback
1755  * sending for each netif (0 = disabled)
1756  */
1757 #if !defined LWIP_LOOPBACK_MAX_PBUFS || defined __DOXYGEN__
1758 #define LWIP_LOOPBACK_MAX_PBUFS         0
1759 #endif
1760 
1761 /**
1762  * LWIP_NETIF_LOOPBACK_MULTITHREADING: Indicates whether threading is enabled in
1763  * the system, as netifs must change how they behave depending on this setting
1764  * for the LWIP_NETIF_LOOPBACK option to work.
1765  * Setting this is needed to avoid reentering non-reentrant functions like
1766  * tcp_input().
1767  *    LWIP_NETIF_LOOPBACK_MULTITHREADING==1: Indicates that the user is using a
1768  *       multithreaded environment like tcpip.c. In this case, netif->input()
1769  *       is called directly.
1770  *    LWIP_NETIF_LOOPBACK_MULTITHREADING==0: Indicates a polling (or NO_SYS) setup.
1771  *       The packets are put on a list and netif_poll() must be called in
1772  *       the main application loop.
1773  */
1774 #if !defined LWIP_NETIF_LOOPBACK_MULTITHREADING || defined __DOXYGEN__
1775 #define LWIP_NETIF_LOOPBACK_MULTITHREADING    (!NO_SYS)
1776 #endif
1777 /**
1778  * @}
1779  */
1780 
1781 /*
1782    ------------------------------------
1783    ---------- Thread options ----------
1784    ------------------------------------
1785 */
1786 /**
1787  * @defgroup lwip_opts_thread Threading
1788  * @ingroup lwip_opts_infrastructure
1789  * @{
1790  */
1791 /**
1792  * TCPIP_THREAD_NAME: The name assigned to the main tcpip thread.
1793  */
1794 #if !defined TCPIP_THREAD_NAME || defined __DOXYGEN__
1795 #define TCPIP_THREAD_NAME               "tcpip_thread"
1796 #endif
1797 
1798 /**
1799  * TCPIP_THREAD_STACKSIZE: The stack size used by the main tcpip thread.
1800  * The stack size value itself is platform-dependent, but is passed to
1801  * sys_thread_new() when the thread is created.
1802  */
1803 #if !defined TCPIP_THREAD_STACKSIZE || defined __DOXYGEN__
1804 #define TCPIP_THREAD_STACKSIZE          0
1805 #endif
1806 
1807 /**
1808  * TCPIP_THREAD_PRIO: The priority assigned to the main tcpip thread.
1809  * The priority value itself is platform-dependent, but is passed to
1810  * sys_thread_new() when the thread is created.
1811  */
1812 #if !defined TCPIP_THREAD_PRIO || defined __DOXYGEN__
1813 #define TCPIP_THREAD_PRIO               1
1814 #endif
1815 
1816 /**
1817  * TCPIP_MBOX_SIZE: The mailbox size for the tcpip thread messages
1818  * The queue size value itself is platform-dependent, but is passed to
1819  * sys_mbox_new() when tcpip_init is called.
1820  */
1821 #if !defined TCPIP_MBOX_SIZE || defined __DOXYGEN__
1822 #define TCPIP_MBOX_SIZE                 0
1823 #endif
1824 
1825 /**
1826  * Define this to something that triggers a watchdog. This is called from
1827  * tcpip_thread after processing a message.
1828  */
1829 #if !defined LWIP_TCPIP_THREAD_ALIVE || defined __DOXYGEN__
1830 #define LWIP_TCPIP_THREAD_ALIVE()
1831 #endif
1832 
1833 /**
1834  * SLIPIF_THREAD_NAME: The name assigned to the slipif_loop thread.
1835  */
1836 #if !defined SLIPIF_THREAD_NAME || defined __DOXYGEN__
1837 #define SLIPIF_THREAD_NAME              "slipif_loop"
1838 #endif
1839 
1840 /**
1841  * SLIP_THREAD_STACKSIZE: The stack size used by the slipif_loop thread.
1842  * The stack size value itself is platform-dependent, but is passed to
1843  * sys_thread_new() when the thread is created.
1844  */
1845 #if !defined SLIPIF_THREAD_STACKSIZE || defined __DOXYGEN__
1846 #define SLIPIF_THREAD_STACKSIZE         0
1847 #endif
1848 
1849 /**
1850  * SLIPIF_THREAD_PRIO: The priority assigned to the slipif_loop thread.
1851  * The priority value itself is platform-dependent, but is passed to
1852  * sys_thread_new() when the thread is created.
1853  */
1854 #if !defined SLIPIF_THREAD_PRIO || defined __DOXYGEN__
1855 #define SLIPIF_THREAD_PRIO              1
1856 #endif
1857 
1858 /**
1859  * DEFAULT_THREAD_NAME: The name assigned to any other lwIP thread.
1860  */
1861 #if !defined DEFAULT_THREAD_NAME || defined __DOXYGEN__
1862 #define DEFAULT_THREAD_NAME             "lwIP"
1863 #endif
1864 
1865 /**
1866  * DEFAULT_THREAD_STACKSIZE: The stack size used by any other lwIP thread.
1867  * The stack size value itself is platform-dependent, but is passed to
1868  * sys_thread_new() when the thread is created.
1869  */
1870 #if !defined DEFAULT_THREAD_STACKSIZE || defined __DOXYGEN__
1871 #define DEFAULT_THREAD_STACKSIZE        0
1872 #endif
1873 
1874 /**
1875  * DEFAULT_THREAD_PRIO: The priority assigned to any other lwIP thread.
1876  * The priority value itself is platform-dependent, but is passed to
1877  * sys_thread_new() when the thread is created.
1878  */
1879 #if !defined DEFAULT_THREAD_PRIO || defined __DOXYGEN__
1880 #define DEFAULT_THREAD_PRIO             1
1881 #endif
1882 
1883 /**
1884  * DEFAULT_RAW_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
1885  * NETCONN_RAW. The queue size value itself is platform-dependent, but is passed
1886  * to sys_mbox_new() when the recvmbox is created.
1887  */
1888 #if !defined DEFAULT_RAW_RECVMBOX_SIZE || defined __DOXYGEN__
1889 #define DEFAULT_RAW_RECVMBOX_SIZE       0
1890 #endif
1891 
1892 /**
1893  * DEFAULT_UDP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
1894  * NETCONN_UDP. The queue size value itself is platform-dependent, but is passed
1895  * to sys_mbox_new() when the recvmbox is created.
1896  */
1897 #if !defined DEFAULT_UDP_RECVMBOX_SIZE || defined __DOXYGEN__
1898 #define DEFAULT_UDP_RECVMBOX_SIZE       0
1899 #endif
1900 
1901 /**
1902  * DEFAULT_TCP_RECVMBOX_SIZE: The mailbox size for the incoming packets on a
1903  * NETCONN_TCP. The queue size value itself is platform-dependent, but is passed
1904  * to sys_mbox_new() when the recvmbox is created.
1905  */
1906 #if !defined DEFAULT_TCP_RECVMBOX_SIZE || defined __DOXYGEN__
1907 #define DEFAULT_TCP_RECVMBOX_SIZE       0
1908 #endif
1909 
1910 /**
1911  * DEFAULT_ACCEPTMBOX_SIZE: The mailbox size for the incoming connections.
1912  * The queue size value itself is platform-dependent, but is passed to
1913  * sys_mbox_new() when the acceptmbox is created.
1914  */
1915 #if !defined DEFAULT_ACCEPTMBOX_SIZE || defined __DOXYGEN__
1916 #define DEFAULT_ACCEPTMBOX_SIZE         0
1917 #endif
1918 /**
1919  * @}
1920  */
1921 
1922 /*
1923    ----------------------------------------------
1924    ---------- Sequential layer options ----------
1925    ----------------------------------------------
1926 */
1927 /**
1928  * @defgroup lwip_opts_netconn Netconn
1929  * @ingroup lwip_opts_threadsafe_apis
1930  * @{
1931  */
1932 /**
1933  * LWIP_NETCONN==1: Enable Netconn API (require to use api_lib.c)
1934  */
1935 #if !defined LWIP_NETCONN || defined __DOXYGEN__
1936 #define LWIP_NETCONN                    1
1937 #endif
1938 
1939 /** LWIP_TCPIP_TIMEOUT==1: Enable tcpip_timeout/tcpip_untimeout to create
1940  * timers running in tcpip_thread from another thread.
1941  */
1942 #if !defined LWIP_TCPIP_TIMEOUT || defined __DOXYGEN__
1943 #define LWIP_TCPIP_TIMEOUT              0
1944 #endif
1945 
1946 /** LWIP_NETCONN_SEM_PER_THREAD==1: Use one (thread-local) semaphore per
1947  * thread calling socket/netconn functions instead of allocating one
1948  * semaphore per netconn (and per select etc.)
1949  * ATTENTION: a thread-local semaphore for API calls is needed:
1950  * - LWIP_NETCONN_THREAD_SEM_GET() returning a sys_sem_t*
1951  * - LWIP_NETCONN_THREAD_SEM_ALLOC() creating the semaphore
1952  * - LWIP_NETCONN_THREAD_SEM_FREE() freeing the semaphore
1953  * The latter 2 can be invoked up by calling netconn_thread_init()/netconn_thread_cleanup().
1954  * Ports may call these for threads created with sys_thread_new().
1955  */
1956 #if !defined LWIP_NETCONN_SEM_PER_THREAD || defined __DOXYGEN__
1957 #define LWIP_NETCONN_SEM_PER_THREAD     0
1958 #endif
1959 
1960 /** LWIP_NETCONN_FULLDUPLEX==1: Enable code that allows reading from one thread,
1961  * writing from a 2nd thread and closing from a 3rd thread at the same time.
1962  * ATTENTION: This is currently really alpha! Some requirements:
1963  * - LWIP_NETCONN_SEM_PER_THREAD==1 is required to use one socket/netconn from
1964  *   multiple threads at once
1965  * - sys_mbox_free() has to unblock receive tasks waiting on recvmbox/acceptmbox
1966  *   and prevent a task pending on this during/after deletion
1967  */
1968 #if !defined LWIP_NETCONN_FULLDUPLEX || defined __DOXYGEN__
1969 #define LWIP_NETCONN_FULLDUPLEX         0
1970 #endif
1971 /**
1972  * @}
1973  */
1974 
1975 /*
1976    ------------------------------------
1977    ---------- Socket options ----------
1978    ------------------------------------
1979 */
1980 /**
1981  * @defgroup lwip_opts_socket Sockets
1982  * @ingroup lwip_opts_threadsafe_apis
1983  * @{
1984  */
1985 /**
1986  * LWIP_SOCKET==1: Enable Socket API (require to use sockets.c)
1987  */
1988 #if !defined LWIP_SOCKET || defined __DOXYGEN__
1989 #define LWIP_SOCKET                     1
1990 #endif
1991 
1992 /**
1993  * LWIP_COMPAT_SOCKETS==1: Enable BSD-style sockets functions names through defines.
1994  * LWIP_COMPAT_SOCKETS==2: Same as ==1 but correctly named functions are created.
1995  * While this helps code completion, it might conflict with existing libraries.
1996  * (only used if you use sockets.c)
1997  */
1998 #if !defined LWIP_COMPAT_SOCKETS || defined __DOXYGEN__
1999 #define LWIP_COMPAT_SOCKETS             1
2000 #endif
2001 
2002 /**
2003  * LWIP_POSIX_SOCKETS_IO_NAMES==1: Enable POSIX-style sockets functions names.
2004  * Disable this option if you use a POSIX operating system that uses the same
2005  * names (read, write & close). (only used if you use sockets.c)
2006  */
2007 #if !defined LWIP_POSIX_SOCKETS_IO_NAMES || defined __DOXYGEN__
2008 #define LWIP_POSIX_SOCKETS_IO_NAMES     1
2009 #endif
2010 
2011 /**
2012  * LWIP_SOCKET_OFFSET==n: Increases the file descriptor number created by LwIP with n.
2013  * This can be useful when there are multiple APIs which create file descriptors.
2014  * When they all start with a different offset and you won't make them overlap you can
2015  * re implement read/write/close/ioctl/fnctl to send the requested action to the right
2016  * library (sharing select will need more work though).
2017  */
2018 #if !defined LWIP_SOCKET_OFFSET || defined __DOXYGEN__
2019 #define LWIP_SOCKET_OFFSET              0
2020 #endif
2021 
2022 /**
2023  * LWIP_SOCKET_EXTERNAL_HEADERS==1: Use external headers instead of sockets.h
2024  * and inet.h. In this case, user must provide its own headers by setting the
2025  * values for LWIP_SOCKET_EXTERNAL_HEADER_SOCKETS_H and
2026  * LWIP_SOCKET_EXTERNAL_HEADER_INET_H to appropriate include file names and the
2027  * whole content of the default sockets.h and inet.h is skipped.
2028  */
2029 #if !defined LWIP_SOCKET_EXTERNAL_HEADERS || defined __DOXYGEN__
2030 #define LWIP_SOCKET_EXTERNAL_HEADERS    0
2031 #endif
2032 
2033 /**
2034  * LWIP_TCP_KEEPALIVE==1: Enable TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT
2035  * options processing. Note that TCP_KEEPIDLE and TCP_KEEPINTVL have to be set
2036  * in seconds. (does not require sockets.c, and will affect tcp.c)
2037  */
2038 #if !defined LWIP_TCP_KEEPALIVE || defined __DOXYGEN__
2039 #define LWIP_TCP_KEEPALIVE              0
2040 #endif
2041 
2042 /**
2043  * LWIP_SO_SNDTIMEO==1: Enable send timeout for sockets/netconns and
2044  * SO_SNDTIMEO processing.
2045  */
2046 #if !defined LWIP_SO_SNDTIMEO || defined __DOXYGEN__
2047 #define LWIP_SO_SNDTIMEO                0
2048 #endif
2049 
2050 /**
2051  * LWIP_SO_RCVTIMEO==1: Enable receive timeout for sockets/netconns and
2052  * SO_RCVTIMEO processing.
2053  */
2054 #if !defined LWIP_SO_RCVTIMEO || defined __DOXYGEN__
2055 #define LWIP_SO_RCVTIMEO                0
2056 #endif
2057 
2058 /**
2059  * LWIP_SO_SNDRCVTIMEO_NONSTANDARD==1: SO_RCVTIMEO/SO_SNDTIMEO take an int
2060  * (milliseconds, much like winsock does) instead of a struct timeval (default).
2061  */
2062 #if !defined LWIP_SO_SNDRCVTIMEO_NONSTANDARD || defined __DOXYGEN__
2063 #define LWIP_SO_SNDRCVTIMEO_NONSTANDARD 0
2064 #endif
2065 
2066 /**
2067  * LWIP_SO_RCVBUF==1: Enable SO_RCVBUF processing.
2068  */
2069 #if !defined LWIP_SO_RCVBUF || defined __DOXYGEN__
2070 #define LWIP_SO_RCVBUF                  0
2071 #endif
2072 
2073 /**
2074  * LWIP_SO_LINGER==1: Enable SO_LINGER processing.
2075  */
2076 #if !defined LWIP_SO_LINGER || defined __DOXYGEN__
2077 #define LWIP_SO_LINGER                  0
2078 #endif
2079 
2080 /**
2081  * If LWIP_SO_RCVBUF is used, this is the default value for recv_bufsize.
2082  */
2083 #if !defined RECV_BUFSIZE_DEFAULT || defined __DOXYGEN__
2084 #define RECV_BUFSIZE_DEFAULT            INT_MAX
2085 #endif
2086 
2087 /**
2088  * By default, TCP socket/netconn close waits 20 seconds max to send the FIN
2089  */
2090 #if !defined LWIP_TCP_CLOSE_TIMEOUT_MS_DEFAULT || defined __DOXYGEN__
2091 #define LWIP_TCP_CLOSE_TIMEOUT_MS_DEFAULT 20000
2092 #endif
2093 
2094 /**
2095  * SO_REUSE==1: Enable SO_REUSEADDR option.
2096  */
2097 #if !defined SO_REUSE || defined __DOXYGEN__
2098 #define SO_REUSE                        0
2099 #endif
2100 
2101 /**
2102  * SO_REUSE_RXTOALL==1: Pass a copy of incoming broadcast/multicast packets
2103  * to all local matches if SO_REUSEADDR is turned on.
2104  * WARNING: Adds a memcpy for every packet if passing to more than one pcb!
2105  */
2106 #if !defined SO_REUSE_RXTOALL || defined __DOXYGEN__
2107 #define SO_REUSE_RXTOALL                0
2108 #endif
2109 
2110 /**
2111  * LWIP_FIONREAD_LINUXMODE==0 (default): ioctl/FIONREAD returns the amount of
2112  * pending data in the network buffer. This is the way windows does it. It's
2113  * the default for lwIP since it is smaller.
2114  * LWIP_FIONREAD_LINUXMODE==1: ioctl/FIONREAD returns the size of the next
2115  * pending datagram in bytes. This is the way linux does it. This code is only
2116  * here for compatibility.
2117  */
2118 #if !defined LWIP_FIONREAD_LINUXMODE || defined __DOXYGEN__
2119 #define LWIP_FIONREAD_LINUXMODE         0
2120 #endif
2121 
2122 /**
2123  * LWIP_SOCKET_SELECT==1 (default): enable select() for sockets (uses a netconn
2124  * callback to keep track of events).
2125  * This saves RAM (counters per socket) and code (netconn event callback), which
2126  * should improve performance a bit).
2127  */
2128 #if !defined LWIP_SOCKET_SELECT || defined __DOXYGEN__
2129 #define LWIP_SOCKET_SELECT              1
2130 #endif
2131 
2132 /**
2133  * LWIP_SOCKET_POLL==1 (default): enable poll() for sockets (including
2134  * struct pollfd, nfds_t, and constants)
2135  */
2136 #if !defined LWIP_SOCKET_POLL || defined __DOXYGEN__
2137 #define LWIP_SOCKET_POLL                1
2138 #endif
2139 /**
2140  * @}
2141  */
2142 
2143 /*
2144    ----------------------------------------
2145    ---------- Statistics options ----------
2146    ----------------------------------------
2147 */
2148 /**
2149  * @defgroup lwip_opts_stats Statistics
2150  * @ingroup lwip_opts_debug
2151  * @{
2152  */
2153 /**
2154  * LWIP_STATS==1: Enable statistics collection in lwip_stats.
2155  */
2156 #if !defined LWIP_STATS || defined __DOXYGEN__
2157 #define LWIP_STATS                      1
2158 #endif
2159 
2160 #if LWIP_STATS
2161 
2162 /**
2163  * LWIP_STATS_DISPLAY==1: Compile in the statistics output functions.
2164  */
2165 #if !defined LWIP_STATS_DISPLAY || defined __DOXYGEN__
2166 #define LWIP_STATS_DISPLAY              0
2167 #endif
2168 
2169 /**
2170  * LINK_STATS==1: Enable link stats.
2171  */
2172 #if !defined LINK_STATS || defined __DOXYGEN__
2173 #define LINK_STATS                      1
2174 #endif
2175 
2176 /**
2177  * ETHARP_STATS==1: Enable etharp stats.
2178  */
2179 #if !defined ETHARP_STATS || defined __DOXYGEN__
2180 #define ETHARP_STATS                    (LWIP_ARP)
2181 #endif
2182 
2183 /**
2184  * IP_STATS==1: Enable IP stats.
2185  */
2186 #if !defined IP_STATS || defined __DOXYGEN__
2187 #define IP_STATS                        1
2188 #endif
2189 
2190 /**
2191  * IPFRAG_STATS==1: Enable IP fragmentation stats. Default is
2192  * on if using either frag or reass.
2193  */
2194 #if !defined IPFRAG_STATS || defined __DOXYGEN__
2195 #define IPFRAG_STATS                    (IP_REASSEMBLY || IP_FRAG)
2196 #endif
2197 
2198 /**
2199  * ICMP_STATS==1: Enable ICMP stats.
2200  */
2201 #if !defined ICMP_STATS || defined __DOXYGEN__
2202 #define ICMP_STATS                      1
2203 #endif
2204 
2205 /**
2206  * IGMP_STATS==1: Enable IGMP stats.
2207  */
2208 #if !defined IGMP_STATS || defined __DOXYGEN__
2209 #define IGMP_STATS                      (LWIP_IGMP)
2210 #endif
2211 
2212 /**
2213  * UDP_STATS==1: Enable UDP stats. Default is on if
2214  * UDP enabled, otherwise off.
2215  */
2216 #if !defined UDP_STATS || defined __DOXYGEN__
2217 #define UDP_STATS                       (LWIP_UDP)
2218 #endif
2219 
2220 /**
2221  * TCP_STATS==1: Enable TCP stats. Default is on if TCP
2222  * enabled, otherwise off.
2223  */
2224 #if !defined TCP_STATS || defined __DOXYGEN__
2225 #define TCP_STATS                       (LWIP_TCP)
2226 #endif
2227 
2228 /**
2229  * MEM_STATS==1: Enable mem.c stats.
2230  */
2231 #if !defined MEM_STATS || defined __DOXYGEN__
2232 #define MEM_STATS                       ((MEM_LIBC_MALLOC == 0) && (MEM_USE_POOLS == 0))
2233 #endif
2234 
2235 /**
2236  * MEMP_STATS==1: Enable memp.c pool stats.
2237  */
2238 #if !defined MEMP_STATS || defined __DOXYGEN__
2239 #define MEMP_STATS                      (MEMP_MEM_MALLOC == 0)
2240 #endif
2241 
2242 /**
2243  * SYS_STATS==1: Enable system stats (sem and mbox counts, etc).
2244  */
2245 #if !defined SYS_STATS || defined __DOXYGEN__
2246 #define SYS_STATS                       (NO_SYS == 0)
2247 #endif
2248 
2249 /**
2250  * IP6_STATS==1: Enable IPv6 stats.
2251  */
2252 #if !defined IP6_STATS || defined __DOXYGEN__
2253 #define IP6_STATS                       (LWIP_IPV6)
2254 #endif
2255 
2256 /**
2257  * ICMP6_STATS==1: Enable ICMP for IPv6 stats.
2258  */
2259 #if !defined ICMP6_STATS || defined __DOXYGEN__
2260 #define ICMP6_STATS                     (LWIP_IPV6 && LWIP_ICMP6)
2261 #endif
2262 
2263 /**
2264  * IP6_FRAG_STATS==1: Enable IPv6 fragmentation stats.
2265  */
2266 #if !defined IP6_FRAG_STATS || defined __DOXYGEN__
2267 #define IP6_FRAG_STATS                  (LWIP_IPV6 && (LWIP_IPV6_FRAG || LWIP_IPV6_REASS))
2268 #endif
2269 
2270 /**
2271  * MLD6_STATS==1: Enable MLD for IPv6 stats.
2272  */
2273 #if !defined MLD6_STATS || defined __DOXYGEN__
2274 #define MLD6_STATS                      (LWIP_IPV6 && LWIP_IPV6_MLD)
2275 #endif
2276 
2277 /**
2278  * ND6_STATS==1: Enable Neighbor discovery for IPv6 stats.
2279  */
2280 #if !defined ND6_STATS || defined __DOXYGEN__
2281 #define ND6_STATS                       (LWIP_IPV6)
2282 #endif
2283 
2284 /**
2285  * MIB2_STATS==1: Stats for SNMP MIB2.
2286  */
2287 #if !defined MIB2_STATS || defined __DOXYGEN__
2288 #define MIB2_STATS                      0
2289 #endif
2290 
2291 #else
2292 
2293 #define LINK_STATS                      0
2294 #define ETHARP_STATS                    0
2295 #define IP_STATS                        0
2296 #define IPFRAG_STATS                    0
2297 #define ICMP_STATS                      0
2298 #define IGMP_STATS                      0
2299 #define UDP_STATS                       0
2300 #define TCP_STATS                       0
2301 #define MEM_STATS                       0
2302 #define MEMP_STATS                      0
2303 #define SYS_STATS                       0
2304 #define LWIP_STATS_DISPLAY              0
2305 #define IP6_STATS                       0
2306 #define ICMP6_STATS                     0
2307 #define IP6_FRAG_STATS                  0
2308 #define MLD6_STATS                      0
2309 #define ND6_STATS                       0
2310 #define MIB2_STATS                      0
2311 
2312 #endif /* LWIP_STATS */
2313 /**
2314  * @}
2315  */
2316 
2317 /*
2318    --------------------------------------
2319    ---------- Checksum options ----------
2320    --------------------------------------
2321 */
2322 /**
2323  * @defgroup lwip_opts_checksum Checksum
2324  * @ingroup lwip_opts_infrastructure
2325  * @{
2326  */
2327 /**
2328  * LWIP_CHECKSUM_CTRL_PER_NETIF==1: Checksum generation/check can be enabled/disabled
2329  * per netif.
2330  * ATTENTION: if enabled, the CHECKSUM_GEN_* and CHECKSUM_CHECK_* defines must be enabled!
2331  */
2332 #if !defined LWIP_CHECKSUM_CTRL_PER_NETIF || defined __DOXYGEN__
2333 #define LWIP_CHECKSUM_CTRL_PER_NETIF    0
2334 #endif
2335 
2336 /**
2337  * CHECKSUM_GEN_IP==1: Generate checksums in software for outgoing IP packets.
2338  */
2339 #if !defined CHECKSUM_GEN_IP || defined __DOXYGEN__
2340 #define CHECKSUM_GEN_IP                 1
2341 #endif
2342 
2343 /**
2344  * CHECKSUM_GEN_UDP==1: Generate checksums in software for outgoing UDP packets.
2345  */
2346 #if !defined CHECKSUM_GEN_UDP || defined __DOXYGEN__
2347 #define CHECKSUM_GEN_UDP                1
2348 #endif
2349 
2350 /**
2351  * CHECKSUM_GEN_TCP==1: Generate checksums in software for outgoing TCP packets.
2352  */
2353 #if !defined CHECKSUM_GEN_TCP || defined __DOXYGEN__
2354 #define CHECKSUM_GEN_TCP                1
2355 #endif
2356 
2357 /**
2358  * CHECKSUM_GEN_ICMP==1: Generate checksums in software for outgoing ICMP packets.
2359  */
2360 #if !defined CHECKSUM_GEN_ICMP || defined __DOXYGEN__
2361 #define CHECKSUM_GEN_ICMP               1
2362 #endif
2363 
2364 /**
2365  * CHECKSUM_GEN_ICMP6==1: Generate checksums in software for outgoing ICMP6 packets.
2366  */
2367 #if !defined CHECKSUM_GEN_ICMP6 || defined __DOXYGEN__
2368 #define CHECKSUM_GEN_ICMP6              1
2369 #endif
2370 
2371 /**
2372  * CHECKSUM_CHECK_IP==1: Check checksums in software for incoming IP packets.
2373  */
2374 #if !defined CHECKSUM_CHECK_IP || defined __DOXYGEN__
2375 #define CHECKSUM_CHECK_IP               1
2376 #endif
2377 
2378 /**
2379  * CHECKSUM_CHECK_UDP==1: Check checksums in software for incoming UDP packets.
2380  */
2381 #if !defined CHECKSUM_CHECK_UDP || defined __DOXYGEN__
2382 #define CHECKSUM_CHECK_UDP              1
2383 #endif
2384 
2385 /**
2386  * CHECKSUM_CHECK_TCP==1: Check checksums in software for incoming TCP packets.
2387  */
2388 #if !defined CHECKSUM_CHECK_TCP || defined __DOXYGEN__
2389 #define CHECKSUM_CHECK_TCP              1
2390 #endif
2391 
2392 /**
2393  * CHECKSUM_CHECK_ICMP==1: Check checksums in software for incoming ICMP packets.
2394  */
2395 #if !defined CHECKSUM_CHECK_ICMP || defined __DOXYGEN__
2396 #define CHECKSUM_CHECK_ICMP             1
2397 #endif
2398 
2399 /**
2400  * CHECKSUM_CHECK_ICMP6==1: Check checksums in software for incoming ICMPv6 packets
2401  */
2402 #if !defined CHECKSUM_CHECK_ICMP6 || defined __DOXYGEN__
2403 #define CHECKSUM_CHECK_ICMP6            1
2404 #endif
2405 
2406 /**
2407  * LWIP_CHECKSUM_ON_COPY==1: Calculate checksum when copying data from
2408  * application buffers to pbufs.
2409  */
2410 #if !defined LWIP_CHECKSUM_ON_COPY || defined __DOXYGEN__
2411 #define LWIP_CHECKSUM_ON_COPY           0
2412 #endif
2413 /**
2414  * @}
2415  */
2416 
2417 /*
2418    ---------------------------------------
2419    ---------- IPv6 options ---------------
2420    ---------------------------------------
2421 */
2422 /**
2423  * @defgroup lwip_opts_ipv6 IPv6
2424  * @ingroup lwip_opts
2425  * @{
2426  */
2427 /**
2428  * LWIP_IPV6==1: Enable IPv6
2429  */
2430 #if !defined LWIP_IPV6 || defined __DOXYGEN__
2431 #define LWIP_IPV6                       0
2432 #endif
2433 
2434 /**
2435  * IPV6_REASS_MAXAGE: Maximum time (in multiples of IP6_REASS_TMR_INTERVAL - so seconds, normally)
2436  * a fragmented IP packet waits for all fragments to arrive. If not all fragments arrived
2437  * in this time, the whole packet is discarded.
2438  */
2439 #if !defined IPV6_REASS_MAXAGE || defined __DOXYGEN__
2440 #define IPV6_REASS_MAXAGE               60
2441 #endif
2442 
2443 /**
2444  * LWIP_IPV6_SCOPES==1: Enable support for IPv6 address scopes, ensuring that
2445  * e.g. link-local addresses are really treated as link-local. Disable this
2446  * setting only for single-interface configurations.
2447  * All addresses that have a scope according to the default policy (link-local
2448  * unicast addresses, interface-local and link-local multicast addresses) should
2449  * now have a zone set on them before being passed to the core API, although
2450  * lwIP will currently attempt to select a zone on the caller's behalf when
2451  * necessary. Applications that directly assign IPv6 addresses to interfaces
2452  * (which is NOT recommended) must now ensure that link-local addresses carry
2453  * the netif's zone. See the new ip6_zone.h header file for more information and
2454  * relevant macros. For now it is still possible to turn off scopes support
2455  * through the new LWIP_IPV6_SCOPES option. When upgrading an implementation that
2456  * uses the core API directly, it is highly recommended to enable
2457  * LWIP_IPV6_SCOPES_DEBUG at least for a while, to ensure e.g. proper address
2458  * initialization.
2459  */
2460 #if !defined LWIP_IPV6_SCOPES || defined __DOXYGEN__
2461 #define LWIP_IPV6_SCOPES                (LWIP_IPV6 && !LWIP_SINGLE_NETIF)
2462 #endif
2463 
2464 /**
2465  * LWIP_IPV6_SCOPES_DEBUG==1: Perform run-time checks to verify that addresses
2466  * are properly zoned (see ip6_zone.h on what that means) where it matters.
2467  * Enabling this setting is highly recommended when upgrading from an existing
2468  * installation that is not yet scope-aware; otherwise it may be too expensive.
2469  */
2470 #if !defined LWIP_IPV6_SCOPES_DEBUG || defined __DOXYGEN__
2471 #define LWIP_IPV6_SCOPES_DEBUG          0
2472 #endif
2473 
2474 /**
2475  * LWIP_IPV6_NUM_ADDRESSES: Number of IPv6 addresses per netif.
2476  */
2477 #if !defined LWIP_IPV6_NUM_ADDRESSES || defined __DOXYGEN__
2478 #define LWIP_IPV6_NUM_ADDRESSES         3
2479 #endif
2480 
2481 /**
2482  * LWIP_IPV6_FORWARD==1: Forward IPv6 packets across netifs
2483  */
2484 #if !defined LWIP_IPV6_FORWARD || defined __DOXYGEN__
2485 #define LWIP_IPV6_FORWARD               0
2486 #endif
2487 
2488 /**
2489  * LWIP_IPV6_FRAG==1: Fragment outgoing IPv6 packets that are too big.
2490  */
2491 #if !defined LWIP_IPV6_FRAG || defined __DOXYGEN__
2492 #define LWIP_IPV6_FRAG                  1
2493 #endif
2494 
2495 /**
2496  * LWIP_IPV6_REASS==1: reassemble incoming IPv6 packets that fragmented
2497  */
2498 #if !defined LWIP_IPV6_REASS || defined __DOXYGEN__
2499 #define LWIP_IPV6_REASS                 LWIP_IPV6
2500 #endif
2501 
2502 /**
2503  * LWIP_IPV6_SEND_ROUTER_SOLICIT==1: Send router solicitation messages during
2504  * network startup.
2505  */
2506 #if !defined LWIP_IPV6_SEND_ROUTER_SOLICIT || defined __DOXYGEN__
2507 #define LWIP_IPV6_SEND_ROUTER_SOLICIT   1
2508 #endif
2509 
2510 /**
2511  * LWIP_IPV6_AUTOCONFIG==1: Enable stateless address autoconfiguration as per RFC 4862.
2512  */
2513 #if !defined LWIP_IPV6_AUTOCONFIG || defined __DOXYGEN__
2514 #define LWIP_IPV6_AUTOCONFIG            LWIP_IPV6
2515 #endif
2516 
2517 /**
2518  * LWIP_IPV6_ADDRESS_LIFETIMES==1: Keep valid and preferred lifetimes for each
2519  * IPv6 address. Required for LWIP_IPV6_AUTOCONFIG. May still be enabled
2520  * otherwise, in which case the application may assign address lifetimes with
2521  * the appropriate macros. Addresses with no lifetime are assumed to be static.
2522  * If this option is disabled, all addresses are assumed to be static.
2523  */
2524 #if !defined LWIP_IPV6_ADDRESS_LIFETIMES || defined __DOXYGEN__
2525 #define LWIP_IPV6_ADDRESS_LIFETIMES     LWIP_IPV6_AUTOCONFIG
2526 #endif
2527 
2528 /**
2529  * LWIP_IPV6_DUP_DETECT_ATTEMPTS=[0..7]: Number of duplicate address detection attempts.
2530  */
2531 #if !defined LWIP_IPV6_DUP_DETECT_ATTEMPTS || defined __DOXYGEN__
2532 #define LWIP_IPV6_DUP_DETECT_ATTEMPTS   1
2533 #endif
2534 /**
2535  * @}
2536  */
2537 
2538 /**
2539  * @defgroup lwip_opts_icmp6 ICMP6
2540  * @ingroup lwip_opts_ipv6
2541  * @{
2542  */
2543 /**
2544  * LWIP_ICMP6==1: Enable ICMPv6 (mandatory per RFC)
2545  */
2546 #if !defined LWIP_ICMP6 || defined __DOXYGEN__
2547 #define LWIP_ICMP6                      LWIP_IPV6
2548 #endif
2549 
2550 /**
2551  * LWIP_ICMP6_DATASIZE: bytes from original packet to send back in
2552  * ICMPv6 error messages.
2553  */
2554 #if !defined LWIP_ICMP6_DATASIZE || defined __DOXYGEN__
2555 #define LWIP_ICMP6_DATASIZE             8
2556 #endif
2557 
2558 /**
2559  * LWIP_ICMP6_HL: default hop limit for ICMPv6 messages
2560  */
2561 #if !defined LWIP_ICMP6_HL || defined __DOXYGEN__
2562 #define LWIP_ICMP6_HL                   255
2563 #endif
2564 /**
2565  * @}
2566  */
2567 
2568 /**
2569  * @defgroup lwip_opts_mld6 Multicast listener discovery
2570  * @ingroup lwip_opts_ipv6
2571  * @{
2572  */
2573 /**
2574  * LWIP_IPV6_MLD==1: Enable multicast listener discovery protocol.
2575  * If LWIP_IPV6 is enabled but this setting is disabled, the MAC layer must
2576  * indiscriminately pass all inbound IPv6 multicast traffic to lwIP.
2577  */
2578 #if !defined LWIP_IPV6_MLD || defined __DOXYGEN__
2579 #define LWIP_IPV6_MLD                   LWIP_IPV6
2580 #endif
2581 
2582 /**
2583  * MEMP_NUM_MLD6_GROUP: Max number of IPv6 multicast groups that can be joined.
2584  * There must be enough groups so that each netif can join the solicited-node
2585  * multicast group for each of its local addresses, plus one for MDNS if
2586  * applicable, plus any number of groups to be joined on UDP sockets.
2587  */
2588 #if !defined MEMP_NUM_MLD6_GROUP || defined __DOXYGEN__
2589 #define MEMP_NUM_MLD6_GROUP             4
2590 #endif
2591 /**
2592  * @}
2593  */
2594 
2595 /**
2596  * @defgroup lwip_opts_nd6 Neighbor discovery
2597  * @ingroup lwip_opts_ipv6
2598  * @{
2599  */
2600 /**
2601  * LWIP_ND6_QUEUEING==1: queue outgoing IPv6 packets while MAC address
2602  * is being resolved.
2603  */
2604 #if !defined LWIP_ND6_QUEUEING || defined __DOXYGEN__
2605 #define LWIP_ND6_QUEUEING               LWIP_IPV6
2606 #endif
2607 
2608 /**
2609  * MEMP_NUM_ND6_QUEUE: Max number of IPv6 packets to queue during MAC resolution.
2610  */
2611 #if !defined MEMP_NUM_ND6_QUEUE || defined __DOXYGEN__
2612 #define MEMP_NUM_ND6_QUEUE              20
2613 #endif
2614 
2615 /**
2616  * LWIP_ND6_NUM_NEIGHBORS: Number of entries in IPv6 neighbor cache
2617  */
2618 #if !defined LWIP_ND6_NUM_NEIGHBORS || defined __DOXYGEN__
2619 #define LWIP_ND6_NUM_NEIGHBORS          10
2620 #endif
2621 
2622 /**
2623  * LWIP_ND6_NUM_DESTINATIONS: number of entries in IPv6 destination cache
2624  */
2625 #if !defined LWIP_ND6_NUM_DESTINATIONS || defined __DOXYGEN__
2626 #define LWIP_ND6_NUM_DESTINATIONS       10
2627 #endif
2628 
2629 /**
2630  * LWIP_ND6_NUM_PREFIXES: number of entries in IPv6 on-link prefixes cache
2631  */
2632 #if !defined LWIP_ND6_NUM_PREFIXES || defined __DOXYGEN__
2633 #define LWIP_ND6_NUM_PREFIXES           5
2634 #endif
2635 
2636 /**
2637  * LWIP_ND6_NUM_ROUTERS: number of entries in IPv6 default router cache
2638  */
2639 #if !defined LWIP_ND6_NUM_ROUTERS || defined __DOXYGEN__
2640 #define LWIP_ND6_NUM_ROUTERS            3
2641 #endif
2642 
2643 /**
2644  * LWIP_ND6_MAX_MULTICAST_SOLICIT: max number of multicast solicit messages to send
2645  * (neighbor solicit and router solicit)
2646  */
2647 #if !defined LWIP_ND6_MAX_MULTICAST_SOLICIT || defined __DOXYGEN__
2648 #define LWIP_ND6_MAX_MULTICAST_SOLICIT  3
2649 #endif
2650 
2651 /**
2652  * LWIP_ND6_MAX_UNICAST_SOLICIT: max number of unicast neighbor solicitation messages
2653  * to send during neighbor reachability detection.
2654  */
2655 #if !defined LWIP_ND6_MAX_UNICAST_SOLICIT || defined __DOXYGEN__
2656 #define LWIP_ND6_MAX_UNICAST_SOLICIT    3
2657 #endif
2658 
2659 /**
2660  * Unused: See ND RFC (time in milliseconds).
2661  */
2662 #if !defined LWIP_ND6_MAX_ANYCAST_DELAY_TIME || defined __DOXYGEN__
2663 #define LWIP_ND6_MAX_ANYCAST_DELAY_TIME 1000
2664 #endif
2665 
2666 /**
2667  * Unused: See ND RFC
2668  */
2669 #if !defined LWIP_ND6_MAX_NEIGHBOR_ADVERTISEMENT || defined __DOXYGEN__
2670 #define LWIP_ND6_MAX_NEIGHBOR_ADVERTISEMENT  3
2671 #endif
2672 
2673 /**
2674  * LWIP_ND6_REACHABLE_TIME: default neighbor reachable time (in milliseconds).
2675  * May be updated by router advertisement messages.
2676  */
2677 #if !defined LWIP_ND6_REACHABLE_TIME || defined __DOXYGEN__
2678 #define LWIP_ND6_REACHABLE_TIME         30000
2679 #endif
2680 
2681 /**
2682  * LWIP_ND6_RETRANS_TIMER: default retransmission timer for solicitation messages
2683  */
2684 #if !defined LWIP_ND6_RETRANS_TIMER || defined __DOXYGEN__
2685 #define LWIP_ND6_RETRANS_TIMER          1000
2686 #endif
2687 
2688 /**
2689  * LWIP_ND6_DELAY_FIRST_PROBE_TIME: Delay before first unicast neighbor solicitation
2690  * message is sent, during neighbor reachability detection.
2691  */
2692 #if !defined LWIP_ND6_DELAY_FIRST_PROBE_TIME || defined __DOXYGEN__
2693 #define LWIP_ND6_DELAY_FIRST_PROBE_TIME 5000
2694 #endif
2695 
2696 /**
2697  * LWIP_ND6_ALLOW_RA_UPDATES==1: Allow Router Advertisement messages to update
2698  * Reachable time and retransmission timers, and netif MTU.
2699  */
2700 #if !defined LWIP_ND6_ALLOW_RA_UPDATES || defined __DOXYGEN__
2701 #define LWIP_ND6_ALLOW_RA_UPDATES       1
2702 #endif
2703 
2704 /**
2705  * LWIP_ND6_TCP_REACHABILITY_HINTS==1: Allow TCP to provide Neighbor Discovery
2706  * with reachability hints for connected destinations. This helps avoid sending
2707  * unicast neighbor solicitation messages.
2708  */
2709 #if !defined LWIP_ND6_TCP_REACHABILITY_HINTS || defined __DOXYGEN__
2710 #define LWIP_ND6_TCP_REACHABILITY_HINTS 1
2711 #endif
2712 
2713 /**
2714  * LWIP_ND6_RDNSS_MAX_DNS_SERVERS > 0: Use IPv6 Router Advertisement Recursive
2715  * DNS Server Option (as per RFC 6106) to copy a defined maximum number of DNS
2716  * servers to the DNS module.
2717  */
2718 #if !defined LWIP_ND6_RDNSS_MAX_DNS_SERVERS || defined __DOXYGEN__
2719 #define LWIP_ND6_RDNSS_MAX_DNS_SERVERS  0
2720 #endif
2721 /**
2722  * @}
2723  */
2724 
2725 /**
2726  * @defgroup lwip_opts_dhcpv6 DHCPv6
2727  * @ingroup lwip_opts_ipv6
2728  * @{
2729  */
2730 /**
2731  * LWIP_IPV6_DHCP6==1: enable DHCPv6 stateful/stateless address autoconfiguration.
2732  */
2733 #if !defined LWIP_IPV6_DHCP6 || defined __DOXYGEN__
2734 #define LWIP_IPV6_DHCP6                 0
2735 #endif
2736 
2737 /**
2738  * LWIP_IPV6_DHCP6_STATEFUL==1: enable DHCPv6 stateful address autoconfiguration.
2739  * (not supported, yet!)
2740  */
2741 #if !defined LWIP_IPV6_DHCP6_STATEFUL || defined __DOXYGEN__
2742 #define LWIP_IPV6_DHCP6_STATEFUL        0
2743 #endif
2744 
2745 /**
2746  * LWIP_IPV6_DHCP6_STATELESS==1: enable DHCPv6 stateless address autoconfiguration.
2747  */
2748 #if !defined LWIP_IPV6_DHCP6_STATELESS || defined __DOXYGEN__
2749 #define LWIP_IPV6_DHCP6_STATELESS       LWIP_IPV6_DHCP6
2750 #endif
2751 
2752 /**
2753  * LWIP_DHCP6_GETS_NTP==1: Request NTP servers via DHCPv6. For each
2754  * response packet, a callback is called, which has to be provided by the port:
2755  * void dhcp6_set_ntp_servers(u8_t num_ntp_servers, ip_addr_t* ntp_server_addrs);
2756 */
2757 #if !defined LWIP_DHCP6_GET_NTP_SRV || defined __DOXYGEN__
2758 #define LWIP_DHCP6_GET_NTP_SRV          0
2759 #endif
2760 
2761 /**
2762  * The maximum of NTP servers requested
2763  */
2764 #if !defined LWIP_DHCP6_MAX_NTP_SERVERS || defined __DOXYGEN__
2765 #define LWIP_DHCP6_MAX_NTP_SERVERS      1
2766 #endif
2767 
2768 /**
2769  * LWIP_DHCP6_MAX_DNS_SERVERS > 0: Request DNS servers via DHCPv6.
2770  * DNS servers received in the response are passed to DNS via @ref dns_setserver()
2771  * (up to the maximum limit defined here).
2772  */
2773 #if !defined LWIP_DHCP6_MAX_DNS_SERVERS || defined __DOXYGEN__
2774 #define LWIP_DHCP6_MAX_DNS_SERVERS      DNS_MAX_SERVERS
2775 #endif
2776 /**
2777  * @}
2778  */
2779 
2780 /*
2781    ---------------------------------------
2782    ---------- Hook options ---------------
2783    ---------------------------------------
2784 */
2785 
2786 /**
2787  * @defgroup lwip_opts_hooks Hooks
2788  * @ingroup lwip_opts_infrastructure
2789  * Hooks are undefined by default, define them to a function if you need them.
2790  * @{
2791  */
2792 
2793 /**
2794  * LWIP_HOOK_FILENAME: Custom filename to \#include in files that provide hooks.
2795  * Declare your hook function prototypes in there, you may also \#include all headers
2796  * providing data types that are need in this file.
2797  */
2798 #ifdef __DOXYGEN__
2799 #define LWIP_HOOK_FILENAME "path/to/my/lwip_hooks.h"
2800 #endif
2801 
2802 /**
2803  * LWIP_HOOK_TCP_ISN:
2804  * Hook for generation of the Initial Sequence Number (ISN) for a new TCP
2805  * connection. The default lwIP ISN generation algorithm is very basic and may
2806  * allow for TCP spoofing attacks. This hook provides the means to implement
2807  * the standardized ISN generation algorithm from RFC 6528 (see contrib/adons/tcp_isn),
2808  * or any other desired algorithm as a replacement.
2809  * Called from tcp_connect() and tcp_listen_input() when an ISN is needed for
2810  * a new TCP connection, if TCP support (@ref LWIP_TCP) is enabled.<br>
2811  * Signature:\code{.c}
2812  * 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);
2813  * \endcode
2814  * - it may be necessary to use "struct ip_addr" (ip4_addr, ip6_addr) instead of "ip_addr_t" in function declarations<br>
2815  * Arguments:
2816  * - local_ip: pointer to the local IP address of the connection
2817  * - local_port: local port number of the connection (host-byte order)
2818  * - remote_ip: pointer to the remote IP address of the connection
2819  * - remote_port: remote port number of the connection (host-byte order)<br>
2820  * Return value:
2821  * - the 32-bit Initial Sequence Number to use for the new TCP connection.
2822  */
2823 #ifdef __DOXYGEN__
2824 #define LWIP_HOOK_TCP_ISN(local_ip, local_port, remote_ip, remote_port)
2825 #endif
2826 
2827 /**
2828  * LWIP_HOOK_TCP_INPACKET_PCB:
2829  * Hook for intercepting incoming packets before they are passed to a pcb. This
2830  * allows updating some state or even dropping a packet.
2831  * Signature:\code{.c}
2832  * 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);
2833  * \endcode
2834  * Arguments:
2835  * - pcb: tcp_pcb selected for input of this packet (ATTENTION: this may be
2836  *        struct tcp_pcb_listen if pcb->state == LISTEN)
2837  * - hdr: pointer to tcp header (ATTENTION: tcp options may not be in one piece!)
2838  * - optlen: tcp option length
2839  * - opt1len: tcp option length 1st part
2840  * - opt2: if this is != NULL, tcp options are split among 2 pbufs. In that case,
2841  *         options start at right after the tcp header ('(u8_t*)(hdr + 1)') for
2842  *         the first 'opt1len' bytes and the rest starts at 'opt2'. opt2len can
2843  *         be simply calculated: 'opt2len = optlen - opt1len;'
2844  * - p: input packet, p->payload points to application data (that's why tcp hdr
2845  *      and options are passed in seperately)
2846  * Return value:
2847  * - ERR_OK: continue input of this packet as normal
2848  * - != ERR_OK: drop this packet for input (don't continue input processing)
2849  *
2850  * ATTENTION: don't call any tcp api functions that might change tcp state (pcb
2851  * state or any pcb lists) from this callback!
2852  */
2853 #ifdef __DOXYGEN__
2854 #define LWIP_HOOK_TCP_INPACKET_PCB(pcb, hdr, optlen, opt1len, opt2, p)
2855 #endif
2856 
2857 /**
2858  * LWIP_HOOK_TCP_OUT_TCPOPT_LENGTH:
2859  * Hook for increasing the size of the options allocated with a tcp header.
2860  * Together with LWIP_HOOK_TCP_OUT_ADD_TCPOPTS, this can be used to add custom
2861  * options to outgoing tcp segments.
2862  * Signature:\code{.c}
2863  * u8_t my_hook_tcp_out_tcpopt_length(const struct tcp_pcb *pcb, u8_t internal_option_length);
2864  * \endcode
2865  * Arguments:
2866  * - pcb: tcp_pcb that transmits (ATTENTION: this may be NULL or
2867  *        struct tcp_pcb_listen if pcb->state == LISTEN)
2868  * - internal_option_length: tcp option length used by the stack internally
2869  * Return value:
2870  * - a number of bytes to allocate for tcp options (internal_option_length <= ret <= 40)
2871  *
2872  * ATTENTION: don't call any tcp api functions that might change tcp state (pcb
2873  * state or any pcb lists) from this callback!
2874  */
2875 #ifdef __DOXYGEN__
2876 #define LWIP_HOOK_TCP_OUT_TCPOPT_LENGTH(pcb, internal_len)
2877 #endif
2878 
2879 /**
2880  * LWIP_HOOK_TCP_OUT_ADD_TCPOPTS:
2881  * Hook for adding custom options to outgoing tcp segments.
2882  * Space for these custom options has to be reserved via LWIP_HOOK_TCP_OUT_TCPOPT_LENGTH.
2883  * Signature:\code{.c}
2884  * u32_t *my_hook_tcp_out_add_tcpopts(struct pbuf *p, struct tcp_hdr *hdr, const struct tcp_pcb *pcb, u32_t *opts);
2885  * \endcode
2886  * Arguments:
2887  * - p: output packet, p->payload pointing to tcp header, data follows
2888  * - hdr: tcp header
2889  * - pcb: tcp_pcb that transmits (ATTENTION: this may be NULL or
2890  *        struct tcp_pcb_listen if pcb->state == LISTEN)
2891  * - opts: pointer where to add the custom options (there may already be options
2892  *         between the header and these)
2893  * Return value:
2894  * - pointer pointing directly after the inserted options
2895  *
2896  * ATTENTION: don't call any tcp api functions that might change tcp state (pcb
2897  * state or any pcb lists) from this callback!
2898  */
2899 #ifdef __DOXYGEN__
2900 #define LWIP_HOOK_TCP_OUT_ADD_TCPOPTS(p, hdr, pcb, opts)
2901 #endif
2902 
2903 /**
2904  * LWIP_HOOK_IP4_INPUT(pbuf, input_netif):
2905  * Called from ip_input() (IPv4)
2906  * Signature:\code{.c}
2907  *   int my_hook(struct pbuf *pbuf, struct netif *input_netif);
2908  * \endcode
2909  * Arguments:
2910  * - pbuf: received struct pbuf passed to ip_input()
2911  * - input_netif: struct netif on which the packet has been received
2912  * Return values:
2913  * - 0: Hook has not consumed the packet, packet is processed as normal
2914  * - != 0: Hook has consumed the packet.
2915  * If the hook consumed the packet, 'pbuf' is in the responsibility of the hook
2916  * (i.e. free it when done).
2917  */
2918 #ifdef __DOXYGEN__
2919 #define LWIP_HOOK_IP4_INPUT(pbuf, input_netif)
2920 #endif
2921 
2922 /**
2923  * LWIP_HOOK_IP4_ROUTE(dest):
2924  * Called from ip_route() (IPv4)
2925  * Signature:\code{.c}
2926  *   struct netif *my_hook(const ip4_addr_t *dest);
2927  * \endcode
2928  * Arguments:
2929  * - dest: destination IPv4 address
2930  * Returns values:
2931  * - the destination netif
2932  * - NULL if no destination netif is found. In that case, ip_route() continues as normal.
2933  */
2934 #ifdef __DOXYGEN__
2935 #define LWIP_HOOK_IP4_ROUTE()
2936 #endif
2937 
2938 /**
2939  * LWIP_HOOK_IP4_ROUTE_SRC(src, dest):
2940  * Source-based routing for IPv4 - called from ip_route() (IPv4)
2941  * Signature:\code{.c}
2942  *   struct netif *my_hook(const ip4_addr_t *src, const ip4_addr_t *dest);
2943  * \endcode
2944  * Arguments:
2945  * - src: local/source IPv4 address
2946  * - dest: destination IPv4 address
2947  * Returns values:
2948  * - the destination netif
2949  * - NULL if no destination netif is found. In that case, ip_route() continues as normal.
2950  */
2951 #ifdef __DOXYGEN__
2952 #define LWIP_HOOK_IP4_ROUTE_SRC(src, dest)
2953 #endif
2954 
2955 /**
2956  * LWIP_HOOK_IP4_CANFORWARD(src, dest):
2957  * Check if an IPv4 can be forwarded - called from:
2958  * ip4_input() -> ip4_forward() -> ip4_canforward() (IPv4)
2959  * - source address is available via ip4_current_src_addr()
2960  * - calling an output function in this context (e.g. multicast router) is allowed
2961  * Signature:\code{.c}
2962  *   int my_hook(struct pbuf *p, u32_t dest_addr_hostorder);
2963  * \endcode
2964  * Arguments:
2965  * - p: packet to forward
2966  * - dest: destination IPv4 address
2967  * Returns values:
2968  * - 1: forward
2969  * - 0: don't forward
2970  * - -1: no decision. In that case, ip4_canforward() continues as normal.
2971  */
2972 #ifdef __DOXYGEN__
2973 #define LWIP_HOOK_IP4_CANFORWARD(src, dest)
2974 #endif
2975 
2976 /**
2977  * LWIP_HOOK_ETHARP_GET_GW(netif, dest):
2978  * Called from etharp_output() (IPv4)
2979  * Signature:\code{.c}
2980  *   const ip4_addr_t *my_hook(struct netif *netif, const ip4_addr_t *dest);
2981  * \endcode
2982  * Arguments:
2983  * - netif: the netif used for sending
2984  * - dest: the destination IPv4 address
2985  * Return values:
2986  * - the IPv4 address of the gateway to handle the specified destination IPv4 address
2987  * - NULL, in which case the netif's default gateway is used
2988  *
2989  * The returned address MUST be directly reachable on the specified netif!
2990  * This function is meant to implement advanced IPv4 routing together with
2991  * LWIP_HOOK_IP4_ROUTE(). The actual routing/gateway table implementation is
2992  * not part of lwIP but can e.g. be hidden in the netif's state argument.
2993 */
2994 #ifdef __DOXYGEN__
2995 #define LWIP_HOOK_ETHARP_GET_GW(netif, dest)
2996 #endif
2997 
2998 /**
2999  * LWIP_HOOK_IP6_INPUT(pbuf, input_netif):
3000  * Called from ip6_input() (IPv6)
3001  * Signature:\code{.c}
3002  *   int my_hook(struct pbuf *pbuf, struct netif *input_netif);
3003  * \endcode
3004  * Arguments:
3005  * - pbuf: received struct pbuf passed to ip6_input()
3006  * - input_netif: struct netif on which the packet has been received
3007  * Return values:
3008  * - 0: Hook has not consumed the packet, packet is processed as normal
3009  * - != 0: Hook has consumed the packet.
3010  * If the hook consumed the packet, 'pbuf' is in the responsibility of the hook
3011  * (i.e. free it when done).
3012  */
3013 #ifdef __DOXYGEN__
3014 #define LWIP_HOOK_IP6_INPUT(pbuf, input_netif)
3015 #endif
3016 
3017 /**
3018  * LWIP_HOOK_IP6_ROUTE(src, dest):
3019  * Called from ip_route() (IPv6)
3020  * Signature:\code{.c}
3021  *   struct netif *my_hook(const ip6_addr_t *dest, const ip6_addr_t *src);
3022  * \endcode
3023  * Arguments:
3024  * - src: source IPv6 address
3025  * - dest: destination IPv6 address
3026  * Return values:
3027  * - the destination netif
3028  * - NULL if no destination netif is found. In that case, ip6_route() continues as normal.
3029  */
3030 #ifdef __DOXYGEN__
3031 #define LWIP_HOOK_IP6_ROUTE(src, dest)
3032 #endif
3033 
3034 /**
3035  * LWIP_HOOK_ND6_GET_GW(netif, dest):
3036  * Called from nd6_get_next_hop_entry() (IPv6)
3037  * Signature:\code{.c}
3038  *   const ip6_addr_t *my_hook(struct netif *netif, const ip6_addr_t *dest);
3039  * \endcode
3040  * Arguments:
3041  * - netif: the netif used for sending
3042  * - dest: the destination IPv6 address
3043  * Return values:
3044  * - the IPv6 address of the next hop to handle the specified destination IPv6 address
3045  * - NULL, in which case a NDP-discovered router is used instead
3046  *
3047  * The returned address MUST be directly reachable on the specified netif!
3048  * This function is meant to implement advanced IPv6 routing together with
3049  * LWIP_HOOK_IP6_ROUTE(). The actual routing/gateway table implementation is
3050  * not part of lwIP but can e.g. be hidden in the netif's state argument.
3051 */
3052 #ifdef __DOXYGEN__
3053 #define LWIP_HOOK_ND6_GET_GW(netif, dest)
3054 #endif
3055 
3056 /**
3057  * LWIP_HOOK_VLAN_CHECK(netif, eth_hdr, vlan_hdr):
3058  * Called from ethernet_input() if VLAN support is enabled
3059  * Signature:\code{.c}
3060  *   int my_hook(struct netif *netif, struct eth_hdr *eth_hdr, struct eth_vlan_hdr *vlan_hdr);
3061  * \endcode
3062  * Arguments:
3063  * - netif: struct netif on which the packet has been received
3064  * - eth_hdr: struct eth_hdr of the packet
3065  * - vlan_hdr: struct eth_vlan_hdr of the packet
3066  * Return values:
3067  * - 0: Packet must be dropped.
3068  * - != 0: Packet must be accepted.
3069  */
3070 #ifdef __DOXYGEN__
3071 #define LWIP_HOOK_VLAN_CHECK(netif, eth_hdr, vlan_hdr)
3072 #endif
3073 
3074 /**
3075  * LWIP_HOOK_VLAN_SET:
3076  * Hook can be used to set prio_vid field of vlan_hdr. If you need to store data
3077  * on per-netif basis to implement this callback, see @ref netif_cd.
3078  * Called from ethernet_output() if VLAN support (@ref ETHARP_SUPPORT_VLAN) is enabled.<br>
3079  * Signature:\code{.c}
3080  *   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);
3081  * \endcode
3082  * Arguments:
3083  * - netif: struct netif that the packet will be sent through
3084  * - p: struct pbuf packet to be sent
3085  * - src: source eth address
3086  * - dst: destination eth address
3087  * - eth_type: ethernet type to packet to be sent<br>
3088  *
3089  *
3090  * Return values:
3091  * - &lt;0: Packet shall not contain VLAN header.
3092  * - 0 &lt;= return value &lt;= 0xFFFF: Packet shall contain VLAN header. Return value is prio_vid in host byte order.
3093  */
3094 #ifdef __DOXYGEN__
3095 #define LWIP_HOOK_VLAN_SET(netif, p, src, dst, eth_type)
3096 #endif
3097 
3098 /**
3099  * LWIP_HOOK_MEMP_AVAILABLE(memp_t_type):
3100  * Called from memp_free() when a memp pool was empty and an item is now available
3101  * Signature:\code{.c}
3102  *   void my_hook(memp_t type);
3103  * \endcode
3104  */
3105 #ifdef __DOXYGEN__
3106 #define LWIP_HOOK_MEMP_AVAILABLE(memp_t_type)
3107 #endif
3108 
3109 /**
3110  * LWIP_HOOK_UNKNOWN_ETH_PROTOCOL(pbuf, netif):
3111  * Called from ethernet_input() when an unknown eth type is encountered.
3112  * Signature:\code{.c}
3113  *   err_t my_hook(struct pbuf* pbuf, struct netif* netif);
3114  * \endcode
3115  * Arguments:
3116  * - p: rx packet with unknown eth type
3117  * - netif: netif on which the packet has been received
3118  * Return values:
3119  * - ERR_OK if packet is accepted (hook function now owns the pbuf)
3120  * - any error code otherwise (pbuf is freed)
3121  *
3122  * Payload points to ethernet header!
3123  */
3124 #ifdef __DOXYGEN__
3125 #define LWIP_HOOK_UNKNOWN_ETH_PROTOCOL(pbuf, netif)
3126 #endif
3127 
3128 /**
3129  * LWIP_HOOK_DHCP_APPEND_OPTIONS(netif, dhcp, state, msg, msg_type, options_len_ptr):
3130  * Called from various dhcp functions when sending a DHCP message.
3131  * This hook is called just before the DHCP message trailer is added, so the
3132  * options are at the end of a DHCP message.
3133  * Signature:\code{.c}
3134  *   void my_hook(struct netif *netif, struct dhcp *dhcp, u8_t state, struct dhcp_msg *msg,
3135  *                u8_t msg_type, u16_t *options_len_ptr);
3136  * \endcode
3137  * Arguments:
3138  * - netif: struct netif that the packet will be sent through
3139  * - dhcp: struct dhcp on that netif
3140  * - state: current dhcp state (dhcp_state_enum_t as an u8_t)
3141  * - msg: struct dhcp_msg that will be sent
3142  * - msg_type: dhcp message type to be sent (u8_t)
3143  * - options_len_ptr: pointer to the current length of options in the dhcp_msg "msg"
3144  *                    (must be increased when options are added!)
3145  *
3146  * Options need to appended like this:
3147  *   LWIP_ASSERT("dhcp option overflow", *options_len_ptr + option_len + 2 <= DHCP_OPTIONS_LEN);
3148  *   msg->options[(*options_len_ptr)++] = &lt;option_number&gt;;
3149  *   msg->options[(*options_len_ptr)++] = &lt;option_len&gt;;
3150  *   msg->options[(*options_len_ptr)++] = &lt;option_bytes&gt;;
3151  *   [...]
3152  */
3153 #ifdef __DOXYGEN__
3154 #define LWIP_HOOK_DHCP_APPEND_OPTIONS(netif, dhcp, state, msg, msg_type, options_len_ptr)
3155 #endif
3156 
3157 /**
3158  * LWIP_HOOK_DHCP_PARSE_OPTION(netif, dhcp, state, msg, msg_type, option, len, pbuf, option_value_offset):
3159  * Called from dhcp_parse_reply when receiving a DHCP message.
3160  * This hook is called for every option in the received message that is not handled internally.
3161  * Signature:\code{.c}
3162  *   void my_hook(struct netif *netif, struct dhcp *dhcp, u8_t state, struct dhcp_msg *msg,
3163  *                u8_t msg_type, u8_t option, u8_t option_len, struct pbuf *pbuf, u16_t option_value_offset);
3164  * \endcode
3165  * Arguments:
3166  * - netif: struct netif that the packet will be sent through
3167  * - dhcp: struct dhcp on that netif
3168  * - state: current dhcp state (dhcp_state_enum_t as an u8_t)
3169  * - msg: struct dhcp_msg that was received
3170  * - msg_type: dhcp message type received (u8_t, ATTENTION: only valid after
3171  *             the message type option has been parsed!)
3172  * - option: option value (u8_t)
3173  * - len: option data length (u8_t)
3174  * - pbuf: pbuf where option data is contained
3175  * - option_value_offset: offset in pbuf where option data begins
3176  *
3177  * A nice way to get the option contents is pbuf_get_contiguous():
3178  *  u8_t buf[32];
3179  *  u8_t *ptr = (u8_t*)pbuf_get_contiguous(p, buf, sizeof(buf), LWIP_MIN(option_len, sizeof(buf)), offset);
3180  */
3181 #ifdef __DOXYGEN__
3182 #define LWIP_HOOK_DHCP_PARSE_OPTION(netif, dhcp, state, msg, msg_type, option, len, pbuf, offset)
3183 #endif
3184 
3185 /**
3186  * LWIP_HOOK_DHCP6_APPEND_OPTIONS(netif, dhcp6, state, msg, msg_type, options_len_ptr, max_len):
3187  * Called from various dhcp6 functions when sending a DHCP6 message.
3188  * This hook is called just before the DHCP6 message is sent, so the
3189  * options are at the end of a DHCP6 message.
3190  * Signature:\code{.c}
3191  *   void my_hook(struct netif *netif, struct dhcp6 *dhcp, u8_t state, struct dhcp6_msg *msg,
3192  *                u8_t msg_type, u16_t *options_len_ptr);
3193  * \endcode
3194  * Arguments:
3195  * - netif: struct netif that the packet will be sent through
3196  * - dhcp6: struct dhcp6 on that netif
3197  * - state: current dhcp6 state (dhcp6_state_enum_t as an u8_t)
3198  * - msg: struct dhcp6_msg that will be sent
3199  * - msg_type: dhcp6 message type to be sent (u8_t)
3200  * - options_len_ptr: pointer to the current length of options in the dhcp6_msg "msg"
3201  *                    (must be increased when options are added!)
3202  *
3203  * Options need to appended like this:
3204  *   u8_t *options = (u8_t *)(msg + 1);
3205  *   LWIP_ASSERT("dhcp option overflow", sizeof(struct dhcp6_msg) + *options_len_ptr + newoptlen <= max_len);
3206  *   options[(*options_len_ptr)++] = &lt;option_data&gt;;
3207  *   [...]
3208  */
3209 #ifdef __DOXYGEN__
3210 #define LWIP_HOOK_DHCP6_APPEND_OPTIONS(netif, dhcp6, state, msg, msg_type, options_len_ptr, max_len)
3211 #endif
3212 
3213 /**
3214  * LWIP_HOOK_SOCKETS_SETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3215  * Called from socket API to implement setsockopt() for options not provided by lwIP.
3216  * Core lock is held when this hook is called.
3217  * Signature:\code{.c}
3218  *   int my_hook(int s, struct lwip_sock *sock, int level, int optname, const void *optval, socklen_t optlen, int *err)
3219  * \endcode
3220  * Arguments:
3221  * - s: socket file descriptor
3222  * - sock: internal socket descriptor (see lwip/priv/sockets_priv.h)
3223  * - level: protocol level at which the option resides
3224  * - optname: option to set
3225  * - optval: value to set
3226  * - optlen: size of optval
3227  * - err: output error
3228  * Return values:
3229  * - 0: Hook has not consumed the option, code continues as normal (to internal options)
3230  * - != 0: Hook has consumed the option, 'err' is returned
3231  */
3232 #ifdef __DOXYGEN__
3233 #define LWIP_HOOK_SOCKETS_SETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3234 #endif
3235 
3236 /**
3237  * LWIP_HOOK_SOCKETS_GETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3238  * Called from socket API to implement getsockopt() for options not provided by lwIP.
3239  * Core lock is held when this hook is called.
3240  * Signature:\code{.c}
3241  *   int my_hook(int s, struct lwip_sock *sock, int level, int optname, void *optval, socklen_t *optlen, int *err)
3242  * \endcode
3243  * Arguments:
3244  * - s: socket file descriptor
3245  * - sock: internal socket descriptor (see lwip/priv/sockets_priv.h)
3246  * - level: protocol level at which the option resides
3247  * - optname: option to get
3248  * - optval: value to get
3249  * - optlen: size of optval
3250  * - err: output error
3251  * Return values:
3252  * - 0: Hook has not consumed the option, code continues as normal (to internal options)
3253  * - != 0: Hook has consumed the option, 'err' is returned
3254  */
3255 #ifdef __DOXYGEN__
3256 #define LWIP_HOOK_SOCKETS_GETSOCKOPT(s, sock, level, optname, optval, optlen, err)
3257 #endif
3258 
3259 /**
3260  * LWIP_HOOK_NETCONN_EXTERNAL_RESOLVE(name, addr, addrtype, err)
3261  * Called from netconn APIs (not usable with callback apps) allowing an
3262  * external DNS resolver (which uses sequential API) to handle the query.
3263  * Signature:\code{.c}
3264  *   int my_hook(const char *name, ip_addr_t *addr, u8_t addrtype, err_t *err)
3265  * \endcode
3266  * Arguments:
3267  * - name: hostname to resolve
3268  * - addr: output host address
3269  * - addrtype: type of address to query
3270  * - err: output error
3271  * Return values:
3272  * - 0: Hook has not consumed hostname query, query continues into DNS module
3273  * - != 0: Hook has consumed the query
3274  *
3275  * err must also be checked to determine if the hook consumed the query, but
3276  * the query failed
3277  */
3278 #ifdef __DOXYGEN__
3279 #define LWIP_HOOK_NETCONN_EXTERNAL_RESOLVE(name, addr, addrtype, err)
3280 #endif
3281 /**
3282  * @}
3283  */
3284 
3285 /*
3286    ---------------------------------------
3287    ---------- Debugging options ----------
3288    ---------------------------------------
3289 */
3290 /**
3291  * @defgroup lwip_opts_debugmsg Debug messages
3292  * @ingroup lwip_opts_debug
3293  * @{
3294  */
3295 /**
3296  * LWIP_DBG_MIN_LEVEL: After masking, the value of the debug is
3297  * compared against this value. If it is smaller, then debugging
3298  * messages are written.
3299  * @see debugging_levels
3300  */
3301 #if !defined LWIP_DBG_MIN_LEVEL || defined __DOXYGEN__
3302 #define LWIP_DBG_MIN_LEVEL              LWIP_DBG_LEVEL_ALL
3303 #endif
3304 
3305 /**
3306  * LWIP_DBG_TYPES_ON: A mask that can be used to globally enable/disable
3307  * debug messages of certain types.
3308  * @see debugging_levels
3309  */
3310 #if !defined LWIP_DBG_TYPES_ON || defined __DOXYGEN__
3311 #define LWIP_DBG_TYPES_ON               LWIP_DBG_ON
3312 #endif
3313 
3314 /**
3315  * ETHARP_DEBUG: Enable debugging in etharp.c.
3316  */
3317 #if !defined ETHARP_DEBUG || defined __DOXYGEN__
3318 #define ETHARP_DEBUG                    LWIP_DBG_OFF
3319 #endif
3320 
3321 /**
3322  * NETIF_DEBUG: Enable debugging in netif.c.
3323  */
3324 #if !defined NETIF_DEBUG || defined __DOXYGEN__
3325 #define NETIF_DEBUG                     LWIP_DBG_OFF
3326 #endif
3327 
3328 /**
3329  * PBUF_DEBUG: Enable debugging in pbuf.c.
3330  */
3331 #if !defined PBUF_DEBUG || defined __DOXYGEN__
3332 #define PBUF_DEBUG                      LWIP_DBG_OFF
3333 #endif
3334 
3335 /**
3336  * API_LIB_DEBUG: Enable debugging in api_lib.c.
3337  */
3338 #if !defined API_LIB_DEBUG || defined __DOXYGEN__
3339 #define API_LIB_DEBUG                   LWIP_DBG_OFF
3340 #endif
3341 
3342 /**
3343  * API_MSG_DEBUG: Enable debugging in api_msg.c.
3344  */
3345 #if !defined API_MSG_DEBUG || defined __DOXYGEN__
3346 #define API_MSG_DEBUG                   LWIP_DBG_OFF
3347 #endif
3348 
3349 /**
3350  * SOCKETS_DEBUG: Enable debugging in sockets.c.
3351  */
3352 #if !defined SOCKETS_DEBUG || defined __DOXYGEN__
3353 #define SOCKETS_DEBUG                   LWIP_DBG_OFF
3354 #endif
3355 
3356 /**
3357  * ICMP_DEBUG: Enable debugging in icmp.c.
3358  */
3359 #if !defined ICMP_DEBUG || defined __DOXYGEN__
3360 #define ICMP_DEBUG                      LWIP_DBG_OFF
3361 #endif
3362 
3363 /**
3364  * IGMP_DEBUG: Enable debugging in igmp.c.
3365  */
3366 #if !defined IGMP_DEBUG || defined __DOXYGEN__
3367 #define IGMP_DEBUG                      LWIP_DBG_OFF
3368 #endif
3369 
3370 /**
3371  * INET_DEBUG: Enable debugging in inet.c.
3372  */
3373 #if !defined INET_DEBUG || defined __DOXYGEN__
3374 #define INET_DEBUG                      LWIP_DBG_OFF
3375 #endif
3376 
3377 /**
3378  * IP_DEBUG: Enable debugging for IP.
3379  */
3380 #if !defined IP_DEBUG || defined __DOXYGEN__
3381 #define IP_DEBUG                        LWIP_DBG_OFF
3382 #endif
3383 
3384 /**
3385  * IP_REASS_DEBUG: Enable debugging in ip_frag.c for both frag & reass.
3386  */
3387 #if !defined IP_REASS_DEBUG || defined __DOXYGEN__
3388 #define IP_REASS_DEBUG                  LWIP_DBG_OFF
3389 #endif
3390 
3391 /**
3392  * RAW_DEBUG: Enable debugging in raw.c.
3393  */
3394 #if !defined RAW_DEBUG || defined __DOXYGEN__
3395 #define RAW_DEBUG                       LWIP_DBG_OFF
3396 #endif
3397 
3398 /**
3399  * MEM_DEBUG: Enable debugging in mem.c.
3400  */
3401 #if !defined MEM_DEBUG || defined __DOXYGEN__
3402 #define MEM_DEBUG                       LWIP_DBG_OFF
3403 #endif
3404 
3405 /**
3406  * MEMP_DEBUG: Enable debugging in memp.c.
3407  */
3408 #if !defined MEMP_DEBUG || defined __DOXYGEN__
3409 #define MEMP_DEBUG                      LWIP_DBG_OFF
3410 #endif
3411 
3412 /**
3413  * SYS_DEBUG: Enable debugging in sys.c.
3414  */
3415 #if !defined SYS_DEBUG || defined __DOXYGEN__
3416 #define SYS_DEBUG                       LWIP_DBG_OFF
3417 #endif
3418 
3419 /**
3420  * TIMERS_DEBUG: Enable debugging in timers.c.
3421  */
3422 #if !defined TIMERS_DEBUG || defined __DOXYGEN__
3423 #define TIMERS_DEBUG                    LWIP_DBG_OFF
3424 #endif
3425 
3426 /**
3427  * TCP_DEBUG: Enable debugging for TCP.
3428  */
3429 #if !defined TCP_DEBUG || defined __DOXYGEN__
3430 #define TCP_DEBUG                       LWIP_DBG_OFF
3431 #endif
3432 
3433 /**
3434  * TCP_INPUT_DEBUG: Enable debugging in tcp_in.c for incoming debug.
3435  */
3436 #if !defined TCP_INPUT_DEBUG || defined __DOXYGEN__
3437 #define TCP_INPUT_DEBUG                 LWIP_DBG_OFF
3438 #endif
3439 
3440 /**
3441  * TCP_FR_DEBUG: Enable debugging in tcp_in.c for fast retransmit.
3442  */
3443 #if !defined TCP_FR_DEBUG || defined __DOXYGEN__
3444 #define TCP_FR_DEBUG                    LWIP_DBG_OFF
3445 #endif
3446 
3447 /**
3448  * TCP_RTO_DEBUG: Enable debugging in TCP for retransmit
3449  * timeout.
3450  */
3451 #if !defined TCP_RTO_DEBUG || defined __DOXYGEN__
3452 #define TCP_RTO_DEBUG                   LWIP_DBG_OFF
3453 #endif
3454 
3455 /**
3456  * TCP_CWND_DEBUG: Enable debugging for TCP congestion window.
3457  */
3458 #if !defined TCP_CWND_DEBUG || defined __DOXYGEN__
3459 #define TCP_CWND_DEBUG                  LWIP_DBG_OFF
3460 #endif
3461 
3462 /**
3463  * TCP_WND_DEBUG: Enable debugging in tcp_in.c for window updating.
3464  */
3465 #if !defined TCP_WND_DEBUG || defined __DOXYGEN__
3466 #define TCP_WND_DEBUG                   LWIP_DBG_OFF
3467 #endif
3468 
3469 /**
3470  * TCP_OUTPUT_DEBUG: Enable debugging in tcp_out.c output functions.
3471  */
3472 #if !defined TCP_OUTPUT_DEBUG || defined __DOXYGEN__
3473 #define TCP_OUTPUT_DEBUG                LWIP_DBG_OFF
3474 #endif
3475 
3476 /**
3477  * TCP_RST_DEBUG: Enable debugging for TCP with the RST message.
3478  */
3479 #if !defined TCP_RST_DEBUG || defined __DOXYGEN__
3480 #define TCP_RST_DEBUG                   LWIP_DBG_OFF
3481 #endif
3482 
3483 /**
3484  * TCP_QLEN_DEBUG: Enable debugging for TCP queue lengths.
3485  */
3486 #if !defined TCP_QLEN_DEBUG || defined __DOXYGEN__
3487 #define TCP_QLEN_DEBUG                  LWIP_DBG_OFF
3488 #endif
3489 
3490 /**
3491  * UDP_DEBUG: Enable debugging in UDP.
3492  */
3493 #if !defined UDP_DEBUG || defined __DOXYGEN__
3494 #define UDP_DEBUG                       LWIP_DBG_OFF
3495 #endif
3496 
3497 /**
3498  * TCPIP_DEBUG: Enable debugging in tcpip.c.
3499  */
3500 #if !defined TCPIP_DEBUG || defined __DOXYGEN__
3501 #define TCPIP_DEBUG                     LWIP_DBG_OFF
3502 #endif
3503 
3504 /**
3505  * SLIP_DEBUG: Enable debugging in slipif.c.
3506  */
3507 #if !defined SLIP_DEBUG || defined __DOXYGEN__
3508 #define SLIP_DEBUG                      LWIP_DBG_OFF
3509 #endif
3510 
3511 /**
3512  * DHCP_DEBUG: Enable debugging in dhcp.c.
3513  */
3514 #if !defined DHCP_DEBUG || defined __DOXYGEN__
3515 #define DHCP_DEBUG                      LWIP_DBG_OFF
3516 #endif
3517 
3518 /**
3519  * AUTOIP_DEBUG: Enable debugging in autoip.c.
3520  */
3521 #if !defined AUTOIP_DEBUG || defined __DOXYGEN__
3522 #define AUTOIP_DEBUG                    LWIP_DBG_OFF
3523 #endif
3524 
3525 /**
3526  * ACD_DEBUG: Enable debugging in acd.c.
3527  */
3528 #if !defined ACD_DEBUG || defined __DOXYGEN__
3529 #define ACD_DEBUG                       LWIP_DBG_OFF
3530 #endif
3531 
3532 /**
3533  * DNS_DEBUG: Enable debugging for DNS.
3534  */
3535 #if !defined DNS_DEBUG || defined __DOXYGEN__
3536 #define DNS_DEBUG                       LWIP_DBG_OFF
3537 #endif
3538 
3539 /**
3540  * IP6_DEBUG: Enable debugging for IPv6.
3541  */
3542 #if !defined IP6_DEBUG || defined __DOXYGEN__
3543 #define IP6_DEBUG                       LWIP_DBG_OFF
3544 #endif
3545 
3546 /**
3547  * DHCP6_DEBUG: Enable debugging in dhcp6.c.
3548  */
3549 #if !defined DHCP6_DEBUG || defined __DOXYGEN__
3550 #define DHCP6_DEBUG                     LWIP_DBG_OFF
3551 #endif
3552 /**
3553  * @}
3554  */
3555 
3556 /**
3557  * LWIP_TESTMODE: Changes to make unit test possible
3558  */
3559 #if !defined LWIP_TESTMODE
3560 #define LWIP_TESTMODE                   0
3561 #endif
3562 
3563 /*
3564    --------------------------------------------------
3565    ---------- Performance tracking options ----------
3566    --------------------------------------------------
3567 */
3568 /**
3569  * @defgroup lwip_opts_perf Performance
3570  * @ingroup lwip_opts_debug
3571  * @{
3572  */
3573 /**
3574  * LWIP_PERF: Enable performance testing for lwIP
3575  * (if enabled, arch/perf.h is included)
3576  */
3577 #if !defined LWIP_PERF || defined __DOXYGEN__
3578 #define LWIP_PERF                       0
3579 #endif
3580 /**
3581  * @}
3582  */
3583 
3584 #endif /* LWIP_HDR_OPT_H */
3585