minix/lib/liblwip/dist/src/core/sys.c

   1 /**
   2  * @file
   3  * lwIP Operating System abstraction
   4  *
   5  */
   6
   7 /*
   8  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without modification,
  12  * are permitted provided that the following conditions are met:
  13  *
  14  * 1. Redistributions of source code must retain the above copyright notice,
  15  *    this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright notice,
  17  *    this list of conditions and the following disclaimer in the documentation
  18  *    and/or other materials provided with the distribution.
  19  * 3. The name of the author may not be used to endorse or promote products
  20  *    derived from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  25  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  27  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  30  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  31  * OF SUCH DAMAGE.
  32  *
  33  * This file is part of the lwIP TCP/IP stack.
  34  *
  35  * Author: Adam Dunkels <adam@sics.se>
  36  *
  37  */
  38
  39 /**
  40  * @defgroup sys_layer Porting (system abstraction layer)
  41  * @ingroup lwip
  42  * @verbinclude "sys_arch.txt"
  43  *
  44  * @defgroup sys_os OS abstraction layer
  45  * @ingroup sys_layer
  46  * No need to implement functions in this section in NO_SYS mode.
  47  *
  48  * @defgroup sys_sem Semaphores
  49  * @ingroup sys_os
  50  *
  51  * @defgroup sys_mutex Mutexes
  52  * @ingroup sys_os
  53  * Mutexes are recommended to correctly handle priority inversion,
  54  * especially if you use LWIP_CORE_LOCKING .
  55  *
  56  * @defgroup sys_mbox Mailboxes
  57  * @ingroup sys_os
  58  *
  59  * @defgroup sys_time Time
  60  * @ingroup sys_layer
  61  *
  62  * @defgroup sys_prot Critical sections
  63  * @ingroup sys_layer
  64  * Used to protect short regions of code against concurrent access.
  65  * - Your system is a bare-metal system (probably with an RTOS)
  66  *   and interrupts are under your control:
  67  *   Implement this as LockInterrupts() / UnlockInterrupts()
  68  * - Your system uses an RTOS with deferred interrupt handling from a
  69  *   worker thread: Implement as a global mutex or lock/unlock scheduler
  70  * - Your system uses a high-level OS with e.g. POSIX signals:
  71  *   Implement as a global mutex
  72  *
  73  * @defgroup sys_misc Misc
  74  * @ingroup sys_os
  75  */
  76
  77 #include "lwip/opt.h"
  78
  79 #include "lwip/sys.h"
  80
  81 /* Most of the functions defined in sys.h must be implemented in the
  82  * architecture-dependent file sys_arch.c */
  83
  84 #if !NO_SYS
  85
  86 #ifndef sys_msleep
  87 /**
  88  * Sleep for some ms. Timeouts are NOT processed while sleeping.
  89  *
  90  * @param ms number of milliseconds to sleep
  91  */
  92 void
  93 sys_msleep(u32_t ms)
  94 {
  95   if (ms > 0) {
  96     sys_sem_t delaysem;
  97     err_t err = sys_sem_new(&delaysem, 0);
  98     if (err == ERR_OK) {
  99       sys_arch_sem_wait(&delaysem, ms);
 100       sys_sem_free(&delaysem);
 101     }
 102   }
 103 }
 104 #endif /* sys_msleep */
 105
 106 #endif /* !NO_SYS */