BadVPN – Blame information for rev 1

Subversion Repositories:
Rev:
Rev Author Line No. Line
1 office 1 /**
2 * @file
3 * OS abstraction layer
4 */
5  
6 /*
7 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without modification,
11 * are permitted provided that the following conditions are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright notice,
14 * this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
22 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
24 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
26 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
29 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
30 * OF SUCH DAMAGE.
31 *
32 * This file is part of the lwIP TCP/IP stack.
33 *
34 * Author: Adam Dunkels <adam@sics.se>
35 */
36  
37 #ifndef LWIP_HDR_SYS_H
38 #define LWIP_HDR_SYS_H
39  
40 #include "lwip/opt.h"
41  
42 #ifdef __cplusplus
43 extern "C" {
44 #endif
45  
46 #if NO_SYS
47  
48 /* For a totally minimal and standalone system, we provide null
49 definitions of the sys_ functions. */
50 typedef u8_t sys_sem_t;
51 typedef u8_t sys_mutex_t;
52 typedef u8_t sys_mbox_t;
53  
54 #define sys_sem_new(s, c) ERR_OK
55 #define sys_sem_signal(s)
56 #define sys_sem_wait(s)
57 #define sys_arch_sem_wait(s,t)
58 #define sys_sem_free(s)
59 #define sys_sem_valid(s) 0
60 #define sys_sem_valid_val(s) 0
61 #define sys_sem_set_invalid(s)
62 #define sys_sem_set_invalid_val(s)
63 #define sys_mutex_new(mu) ERR_OK
64 #define sys_mutex_lock(mu)
65 #define sys_mutex_unlock(mu)
66 #define sys_mutex_free(mu)
67 #define sys_mutex_valid(mu) 0
68 #define sys_mutex_set_invalid(mu)
69 #define sys_mbox_new(m, s) ERR_OK
70 #define sys_mbox_fetch(m,d)
71 #define sys_mbox_tryfetch(m,d)
72 #define sys_mbox_post(m,d)
73 #define sys_mbox_trypost(m,d)
74 #define sys_mbox_free(m)
75 #define sys_mbox_valid(m)
76 #define sys_mbox_valid_val(m)
77 #define sys_mbox_set_invalid(m)
78 #define sys_mbox_set_invalid_val(m)
79  
80 #define sys_thread_new(n,t,a,s,p)
81  
82 #define sys_msleep(t)
83  
84 #else /* NO_SYS */
85  
86 /** Return code for timeouts from sys_arch_mbox_fetch and sys_arch_sem_wait */
87 #define SYS_ARCH_TIMEOUT 0xffffffffUL
88  
89 /** sys_mbox_tryfetch() returns SYS_MBOX_EMPTY if appropriate.
90 * For now we use the same magic value, but we allow this to change in future.
91 */
92 #define SYS_MBOX_EMPTY SYS_ARCH_TIMEOUT
93  
94 #include "lwip/err.h"
95 #include "arch/sys_arch.h"
96  
97 /** Function prototype for thread functions */
98 typedef void (*lwip_thread_fn)(void *arg);
99  
100 /* Function prototypes for functions to be implemented by platform ports
101 (in sys_arch.c) */
102  
103 /* Mutex functions: */
104  
105 /** Define LWIP_COMPAT_MUTEX if the port has no mutexes and binary semaphores
106 should be used instead */
107 #ifndef LWIP_COMPAT_MUTEX
108 #define LWIP_COMPAT_MUTEX 0
109 #endif
110  
111 #if LWIP_COMPAT_MUTEX
112 /* for old ports that don't have mutexes: define them to binary semaphores */
113 #define sys_mutex_t sys_sem_t
114 #define sys_mutex_new(mutex) sys_sem_new(mutex, 1)
115 #define sys_mutex_lock(mutex) sys_sem_wait(mutex)
116 #define sys_mutex_unlock(mutex) sys_sem_signal(mutex)
117 #define sys_mutex_free(mutex) sys_sem_free(mutex)
118 #define sys_mutex_valid(mutex) sys_sem_valid(mutex)
119 #define sys_mutex_set_invalid(mutex) sys_sem_set_invalid(mutex)
120  
121 #else /* LWIP_COMPAT_MUTEX */
122  
123 /**
124 * @ingroup sys_mutex
125 * Create a new mutex.
126 * Note that mutexes are expected to not be taken recursively by the lwIP code,
127 * so both implementation types (recursive or non-recursive) should work.
128 * @param mutex pointer to the mutex to create
129 * @return ERR_OK if successful, another err_t otherwise
130 */
131 err_t sys_mutex_new(sys_mutex_t *mutex);
132 /**
133 * @ingroup sys_mutex
134 * Lock a mutex
135 * @param mutex the mutex to lock
136 */
137 void sys_mutex_lock(sys_mutex_t *mutex);
138 /**
139 * @ingroup sys_mutex
140 * Unlock a mutex
141 * @param mutex the mutex to unlock
142 */
143 void sys_mutex_unlock(sys_mutex_t *mutex);
144 /**
145 * @ingroup sys_mutex
146 * Delete a semaphore
147 * @param mutex the mutex to delete
148 */
149 void sys_mutex_free(sys_mutex_t *mutex);
150 #ifndef sys_mutex_valid
151 /**
152 * @ingroup sys_mutex
153 * Check if a mutex is valid/allocated: return 1 for valid, 0 for invalid
154 */
155 int sys_mutex_valid(sys_mutex_t *mutex);
156 #endif
157 #ifndef sys_mutex_set_invalid
158 /**
159 * @ingroup sys_mutex
160 * Set a mutex invalid so that sys_mutex_valid returns 0
161 */
162 void sys_mutex_set_invalid(sys_mutex_t *mutex);
163 #endif
164 #endif /* LWIP_COMPAT_MUTEX */
165  
166 /* Semaphore functions: */
167  
168 /**
169 * @ingroup sys_sem
170 * Create a new semaphore
171 * @param sem pointer to the semaphore to create
172 * @param count initial count of the semaphore
173 * @return ERR_OK if successful, another err_t otherwise
174 */
175 err_t sys_sem_new(sys_sem_t *sem, u8_t count);
176 /**
177 * @ingroup sys_sem
178 * Signals a semaphore
179 * @param sem the semaphore to signal
180 */
181 void sys_sem_signal(sys_sem_t *sem);
182 /**
183 * @ingroup sys_sem
184 * Wait for a semaphore for the specified timeout
185 * @param sem the semaphore to wait for
186 * @param timeout timeout in milliseconds to wait (0 = wait forever)
187 * @return SYS_ARCH_TIMEOUT on timeout, any other value on success
188 */
189 u32_t sys_arch_sem_wait(sys_sem_t *sem, u32_t timeout);
190 /**
191 * @ingroup sys_sem
192 * Delete a semaphore
193 * @param sem semaphore to delete
194 */
195 void sys_sem_free(sys_sem_t *sem);
196 /** Wait for a semaphore - forever/no timeout */
197 #define sys_sem_wait(sem) sys_arch_sem_wait(sem, 0)
198 #ifndef sys_sem_valid
199 /**
200 * @ingroup sys_sem
201 * Check if a semaphore is valid/allocated: return 1 for valid, 0 for invalid
202 */
203 int sys_sem_valid(sys_sem_t *sem);
204 #endif
205 #ifndef sys_sem_set_invalid
206 /**
207 * @ingroup sys_sem
208 * Set a semaphore invalid so that sys_sem_valid returns 0
209 */
210 void sys_sem_set_invalid(sys_sem_t *sem);
211 #endif
212 #ifndef sys_sem_valid_val
213 /**
214 * Same as sys_sem_valid() but taking a value, not a pointer
215 */
216 #define sys_sem_valid_val(sem) sys_sem_valid(&(sem))
217 #endif
218 #ifndef sys_sem_set_invalid_val
219 /**
220 * Same as sys_sem_set_invalid() but taking a value, not a pointer
221 */
222 #define sys_sem_set_invalid_val(sem) sys_sem_set_invalid(&(sem))
223 #endif
224  
225 #ifndef sys_msleep
226 /**
227 * @ingroup sys_misc
228 * Sleep for specified number of ms
229 */
230 void sys_msleep(u32_t ms); /* only has a (close to) 1 ms resolution. */
231 #endif
232  
233 /* Mailbox functions. */
234  
235 /**
236 * @ingroup sys_mbox
237 * Create a new mbox of specified size
238 * @param mbox pointer to the mbox to create
239 * @param size (minimum) number of messages in this mbox
240 * @return ERR_OK if successful, another err_t otherwise
241 */
242 err_t sys_mbox_new(sys_mbox_t *mbox, int size);
243 /**
244 * @ingroup sys_mbox
245 * Post a message to an mbox - may not fail
246 * -> blocks if full, only used from tasks not from ISR
247 * @param mbox mbox to posts the message
248 * @param msg message to post (ATTENTION: can be NULL)
249 */
250 void sys_mbox_post(sys_mbox_t *mbox, void *msg);
251 /**
252 * @ingroup sys_mbox
253 * Try to post a message to an mbox - may fail if full or ISR
254 * @param mbox mbox to posts the message
255 * @param msg message to post (ATTENTION: can be NULL)
256 */
257 err_t sys_mbox_trypost(sys_mbox_t *mbox, void *msg);
258 /**
259 * @ingroup sys_mbox
260 * Wait for a new message to arrive in the mbox
261 * @param mbox mbox to get a message from
262 * @param msg pointer where the message is stored
263 * @param timeout maximum time (in milliseconds) to wait for a message (0 = wait forever)
264 * @return SYS_ARCH_TIMEOUT on timeout, any other value if a message has been received
265 */
266 u32_t sys_arch_mbox_fetch(sys_mbox_t *mbox, void **msg, u32_t timeout);
267 /* Allow port to override with a macro, e.g. special timeout for sys_arch_mbox_fetch() */
268 #ifndef sys_arch_mbox_tryfetch
269 /**
270 * @ingroup sys_mbox
271 * Wait for a new message to arrive in the mbox
272 * @param mbox mbox to get a message from
273 * @param msg pointer where the message is stored
274 * @return 0 (milliseconds) if a message has been received
275 * or SYS_MBOX_EMPTY if the mailbox is empty
276 */
277 u32_t sys_arch_mbox_tryfetch(sys_mbox_t *mbox, void **msg);
278 #endif
279 /**
280 * For now, we map straight to sys_arch implementation.
281 */
282 #define sys_mbox_tryfetch(mbox, msg) sys_arch_mbox_tryfetch(mbox, msg)
283 /**
284 * @ingroup sys_mbox
285 * Delete an mbox
286 * @param mbox mbox to delete
287 */
288 void sys_mbox_free(sys_mbox_t *mbox);
289 #define sys_mbox_fetch(mbox, msg) sys_arch_mbox_fetch(mbox, msg, 0)
290 #ifndef sys_mbox_valid
291 /**
292 * @ingroup sys_mbox
293 * Check if an mbox is valid/allocated: return 1 for valid, 0 for invalid
294 */
295 int sys_mbox_valid(sys_mbox_t *mbox);
296 #endif
297 #ifndef sys_mbox_set_invalid
298 /**
299 * @ingroup sys_mbox
300 * Set an mbox invalid so that sys_mbox_valid returns 0
301 */
302 void sys_mbox_set_invalid(sys_mbox_t *mbox);
303 #endif
304 #ifndef sys_mbox_valid_val
305 /**
306 * Same as sys_mbox_valid() but taking a value, not a pointer
307 */
308 #define sys_mbox_valid_val(mbox) sys_mbox_valid(&(mbox))
309 #endif
310 #ifndef sys_mbox_set_invalid_val
311 /**
312 * Same as sys_mbox_set_invalid() but taking a value, not a pointer
313 */
314 #define sys_mbox_set_invalid_val(mbox) sys_mbox_set_invalid(&(mbox))
315 #endif
316  
317  
318 /**
319 * @ingroup sys_misc
320 * The only thread function:
321 * Creates a new thread
322 * ATTENTION: although this function returns a value, it MUST NOT FAIL (ports have to assert this!)
323 * @param name human-readable name for the thread (used for debugging purposes)
324 * @param thread thread-function
325 * @param arg parameter passed to 'thread'
326 * @param stacksize stack size in bytes for the new thread (may be ignored by ports)
327 * @param prio priority of the new thread (may be ignored by ports) */
328 sys_thread_t sys_thread_new(const char *name, lwip_thread_fn thread, void *arg, int stacksize, int prio);
329  
330 #endif /* NO_SYS */
331  
332 /* sys_init() must be called before anything else. */
333 void sys_init(void);
334  
335 #ifndef sys_jiffies
336 /**
337 * Ticks/jiffies since power up.
338 */
339 u32_t sys_jiffies(void);
340 #endif
341  
342 /**
343 * @ingroup sys_time
344 * Returns the current time in milliseconds,
345 * may be the same as sys_jiffies or at least based on it.
346 */
347 u32_t sys_now(void);
348  
349 /* Critical Region Protection */
350 /* These functions must be implemented in the sys_arch.c file.
351 In some implementations they can provide a more light-weight protection
352 mechanism than using semaphores. Otherwise semaphores can be used for
353 implementation */
354 #ifndef SYS_ARCH_PROTECT
355 /** SYS_LIGHTWEIGHT_PROT
356 * define SYS_LIGHTWEIGHT_PROT in lwipopts.h if you want inter-task protection
357 * for certain critical regions during buffer allocation, deallocation and memory
358 * allocation and deallocation.
359 */
360 #if SYS_LIGHTWEIGHT_PROT
361  
362 /**
363 * @ingroup sys_prot
364 * SYS_ARCH_DECL_PROTECT
365 * declare a protection variable. This macro will default to defining a variable of
366 * type sys_prot_t. If a particular port needs a different implementation, then
367 * this macro may be defined in sys_arch.h.
368 */
369 #define SYS_ARCH_DECL_PROTECT(lev) sys_prot_t lev
370 /**
371 * @ingroup sys_prot
372 * SYS_ARCH_PROTECT
373 * Perform a "fast" protect. This could be implemented by
374 * disabling interrupts for an embedded system or by using a semaphore or
375 * mutex. The implementation should allow calling SYS_ARCH_PROTECT when
376 * already protected. The old protection level is returned in the variable
377 * "lev". This macro will default to calling the sys_arch_protect() function
378 * which should be implemented in sys_arch.c. If a particular port needs a
379 * different implementation, then this macro may be defined in sys_arch.h
380 */
381 #define SYS_ARCH_PROTECT(lev) lev = sys_arch_protect()
382 /**
383 * @ingroup sys_prot
384 * SYS_ARCH_UNPROTECT
385 * Perform a "fast" set of the protection level to "lev". This could be
386 * implemented by setting the interrupt level to "lev" within the MACRO or by
387 * using a semaphore or mutex. This macro will default to calling the
388 * sys_arch_unprotect() function which should be implemented in
389 * sys_arch.c. If a particular port needs a different implementation, then
390 * this macro may be defined in sys_arch.h
391 */
392 #define SYS_ARCH_UNPROTECT(lev) sys_arch_unprotect(lev)
393 sys_prot_t sys_arch_protect(void);
394 void sys_arch_unprotect(sys_prot_t pval);
395  
396 #else
397  
398 #define SYS_ARCH_DECL_PROTECT(lev)
399 #define SYS_ARCH_PROTECT(lev)
400 #define SYS_ARCH_UNPROTECT(lev)
401  
402 #endif /* SYS_LIGHTWEIGHT_PROT */
403  
404 #endif /* SYS_ARCH_PROTECT */
405  
406 /*
407 * Macros to set/get and increase/decrease variables in a thread-safe way.
408 * Use these for accessing variable that are used from more than one thread.
409 */
410  
411 #ifndef SYS_ARCH_INC
412 #define SYS_ARCH_INC(var, val) do { \
413 SYS_ARCH_DECL_PROTECT(old_level); \
414 SYS_ARCH_PROTECT(old_level); \
415 var += val; \
416 SYS_ARCH_UNPROTECT(old_level); \
417 } while(0)
418 #endif /* SYS_ARCH_INC */
419  
420 #ifndef SYS_ARCH_DEC
421 #define SYS_ARCH_DEC(var, val) do { \
422 SYS_ARCH_DECL_PROTECT(old_level); \
423 SYS_ARCH_PROTECT(old_level); \
424 var -= val; \
425 SYS_ARCH_UNPROTECT(old_level); \
426 } while(0)
427 #endif /* SYS_ARCH_DEC */
428  
429 #ifndef SYS_ARCH_GET
430 #define SYS_ARCH_GET(var, ret) do { \
431 SYS_ARCH_DECL_PROTECT(old_level); \
432 SYS_ARCH_PROTECT(old_level); \
433 ret = var; \
434 SYS_ARCH_UNPROTECT(old_level); \
435 } while(0)
436 #endif /* SYS_ARCH_GET */
437  
438 #ifndef SYS_ARCH_SET
439 #define SYS_ARCH_SET(var, val) do { \
440 SYS_ARCH_DECL_PROTECT(old_level); \
441 SYS_ARCH_PROTECT(old_level); \
442 var = val; \
443 SYS_ARCH_UNPROTECT(old_level); \
444 } while(0)
445 #endif /* SYS_ARCH_SET */
446  
447 #ifndef SYS_ARCH_LOCKED
448 #define SYS_ARCH_LOCKED(code) do { \
449 SYS_ARCH_DECL_PROTECT(old_level); \
450 SYS_ARCH_PROTECT(old_level); \
451 code; \
452 SYS_ARCH_UNPROTECT(old_level); \
453 } while(0)
454 #endif /* SYS_ARCH_LOCKED */
455  
456  
457 #ifdef __cplusplus
458 }
459 #endif
460  
461 #endif /* LWIP_HDR_SYS_H */