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Diffstat (limited to 'nuttx/net/uip/uip_lock.c')
| -rw-r--r-- | nuttx/net/uip/uip_lock.c | 219 |
1 files changed, 0 insertions, 219 deletions
diff --git a/nuttx/net/uip/uip_lock.c b/nuttx/net/uip/uip_lock.c deleted file mode 100644 index 5abcda269..000000000 --- a/nuttx/net/uip/uip_lock.c +++ /dev/null @@ -1,219 +0,0 @@ -/**************************************************************************** - * net/uip/uip_lock.c - * - * Copyright (C) 2011-2012 Gregory Nutt. All rights reserved. - * Author: Gregory Nutt <gnutt@nuttx.org> - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in - * the documentation and/or other materials provided with the - * distribution. - * 3. Neither the name NuttX nor the names of its contributors may be - * used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS - * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE - * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, - * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS - * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED - * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN - * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - * POSSIBILITY OF SUCH DAMAGE. - * - ****************************************************************************/ - -/**************************************************************************** - * Included Files - ****************************************************************************/ - -#include <nuttx/config.h> - -#include <unistd.h> -#include <semaphore.h> -#include <assert.h> -#include <errno.h> -#include <debug.h> - -#include <nuttx/arch.h> -#include <nuttx/net/uip/uip.h> - -#if defined(CONFIG_NET) && defined(CONFIG_NET_NOINTS) - -/**************************************************************************** - * Pre-processor Definitions - ****************************************************************************/ - -#define NO_HOLDER (pid_t)-1 - -/**************************************************************************** - * Private Data - ****************************************************************************/ - -static sem_t g_uipsem; -static pid_t g_holder = NO_HOLDER; -static unsigned int g_count = 0; - -/**************************************************************************** - * Private Functions - ****************************************************************************/ - -/**************************************************************************** - * Function: uip_takesem - * - * Description: - * Take the semaphore - * - ****************************************************************************/ - -static void uip_takesem(void) -{ - while (sem_wait(&g_uipsem) != 0) - { - /* The only case that an error should occur here is if the wait was - * awakened by a signal. - */ - - ASSERT(errno == EINTR); - } -} - -/**************************************************************************** - * Public Functions - ****************************************************************************/ - -/**************************************************************************** - * Function: uip_lockinit - * - * Description: - * Initialize the locking facility - * - ****************************************************************************/ - -void uip_lockinit(void) -{ - sem_init(&g_uipsem, 0, 1); -} - -/**************************************************************************** - * Function: uip_lock - * - * Description: - * Take the lock - * - ****************************************************************************/ - -uip_lock_t uip_lock(void) -{ - pid_t me = getpid(); - - /* Does this thread already hold the semaphore? */ - - if (g_holder == me) - { - /* Yes.. just increment the reference count */ - - g_count++; - } - else - { - /* No.. take the semaphore (perhaps waiting) */ - - uip_takesem(); - - /* Now this thread holds the semaphore */ - - g_holder = me; - g_count = 1; - } - - return 0; -} - -/**************************************************************************** - * Function: uip_unlock - * - * Description: - * Release the lock. - * - ****************************************************************************/ - -void uip_unlock(uip_lock_t flags) -{ - DEBUGASSERT(g_holder == getpid() && g_count > 0); - - /* If the count would go to zero, then release the semaphore */ - - if (g_count == 1) - { - /* We no longer hold the semaphore */ - - g_holder = NO_HOLDER; - g_count = 0; - sem_post(&g_uipsem); - } - else - { - /* We still hold the semaphore. Just decrement the count */ - - g_count--; - } -} - -/**************************************************************************** - * Function: uip_lockedwait - * - * Description: - * Atomically wait for sem while temporarily releasing g_uipsem. - * - ****************************************************************************/ - -int uip_lockedwait(sem_t *sem) -{ - pid_t me = getpid(); - unsigned int count; - irqstate_t flags; - int ret; - - flags = irqsave(); /* No interrupts */ - sched_lock(); /* No context switches */ - if (g_holder == me) - { - /* Release the uIP semaphore, remembering the count */ - - count = g_count; - g_holder = NO_HOLDER; - g_count = 0; - sem_post(&g_uipsem); - - /* Now take the semaphore */ - - ret = sem_wait(sem); - - /* Recover the uIP semaphore at the proper count */ - - uip_takesem(); - g_holder = me; - g_count = count; - } - else - { - ret = sem_wait(sem); - } - - sched_unlock(); - irqrestore(flags); - return ret; - } - -#endif /* CONFIG_NET */ |