reactos/lib/drivers/lwip/src/include/lwip/sys.h

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