Refactor BeRTOS to be in his own directory.

[bertos.git] / kern / sem.c

diff --git a/kern/sem.c b/kern/sem.c
deleted file mode 100644 (file)
index 0f31fa0..0000000
--- a/kern/sem.c
+++ /dev/null
@@ -1,186 +0,0 @@
-/**
- * \file
- * <!--
- * This file is part of BeRTOS.
- *
- * Bertos is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * As a special exception, you may use this file as part of a free software
- * library without restriction.  Specifically, if other files instantiate
- * templates or use macros or inline functions from this file, or you compile
- * this file and link it with other files to produce an executable, this
- * file does not by itself cause the resulting executable to be covered by
- * the GNU General Public License.  This exception does not however
- * invalidate any other reasons why the executable file might be covered by
- * the GNU General Public License.
- *
- * Copyright 2001, 2004 Develer S.r.l. (http://www.develer.com/)
- * Copyright 1999, 2000, 2001 Bernardo Innocenti <bernie@develer.com>
- *
- * -->
- *
- * \brief Semaphore based synchronization services.
- *
- * \version $Id$
- *
- * \author Bernardo Innocenti <bernie@develer.com>
- */
-
-#include "sem.h"
-#include <kern/proc.h>
-#include <kern/proc_p.h>
-#include <kern/signal.h>
-#include <cfg/debug.h>
-
-INLINE void sem_verify(struct Semaphore *s)
-{
-       (void)s;
-       ASSERT(s);
-       LIST_ASSERT_VALID(&s->wait_queue);
-       ASSERT(s->nest_count >= 0);
-       ASSERT(s->nest_count < 128);   // heuristic max
-}
-
-
-/**
- * \brief Initialize a Semaphore structure.
- */
-void sem_init(struct Semaphore *s)
-{
-       LIST_INIT(&s->wait_queue);
-       s->owner = NULL;
-       s->nest_count = 0;
-}
-
-
-/**
- * \brief Attempt to lock a semaphore without waiting.
- *
- * \return true in case of success, false if the semaphore
- *         was already locked by someone else.
- *
- * \note   each call to sem_attempt() must be matched by a
- *         call to sem_release().
- *
- * \see sem_obtain() sem_release()
- */
-bool sem_attempt(struct Semaphore *s)
-{
-       bool result = false;
-
-       proc_forbid();
-       sem_verify(s);
-       if ((!s->owner) || (s->owner == CurrentProcess))
-       {
-               s->owner = CurrentProcess;
-               s->nest_count++;
-               result = true;
-       }
-       proc_permit();
-
-       return result;
-}
-
-
-/**
- * \brief Lock a semaphore.
- *
- * If the semaphore is already owned by another process, the caller
- * process will be enqueued into the waiting list and sleep until
- * the semaphore is available.
- *
- * \note Each call to sem_obtain() must be matched by a
- *       call to sem_release().
- *
- * \note This routine is optimized for highest speed in
- *       the most common case: the semaphore is free or locked
- *       by the calling process itself. Rearranging this code
- *       is probably a bad idea.
- *
- * \sa sem_release() sem_attempt()
- */
-void sem_obtain(struct Semaphore *s)
-{
-       proc_forbid();
-       sem_verify(s);
-
-       /* Is the semaphore already locked by another process? */
-       if (UNLIKELY(s->owner && (s->owner != CurrentProcess)))
-       {
-               /* Append calling process to the wait queue */
-               ADDTAIL(&s->wait_queue, (Node *)CurrentProcess);
-
-               /*
-                * We will wake up only when the current owner calls
-                * sem_release(). Then, the semaphore will already
-                * be locked for us.
-                */
-               proc_permit();
-               proc_schedule();
-       }
-       else
-       {
-               ASSERT(LIST_EMPTY(&s->wait_queue));
-
-               /* The semaphore was free: lock it */
-               s->owner = CurrentProcess;
-               s->nest_count++;
-               proc_permit();
-       }
-}
-
-
-/**
- * \brief Release a lock on a previously locked semaphore.
- *
- * If the nesting count of the semaphore reaches zero,
- * the next process waiting for it will be awaken.
- *
- * \note This routine is optimized for highest speed in
- *       the most common case: the semaphore has been locked just
- *       once and nobody else was waiting for it. Rearranging
- *       this code is probably a bad idea.
- *
- * \sa sem_obtain() sem_attempt()
- */
-void sem_release(struct Semaphore *s)
-{
-       proc_forbid();
-       sem_verify(s);
-
-       ASSERT(s->owner == CurrentProcess);
-
-       /*
-        * Decrement nesting count and check if the semaphore
-        * has been fully unlocked.
-        */
-       if (--s->nest_count == 0)
-       {
-               Process *proc;
-
-               /* Disown semaphore */
-               s->owner = NULL;
-
-               /* Give semaphore to the first applicant, if any */
-               if (UNLIKELY((proc = (Process *)list_remHead(&s->wait_queue))))
-               {
-                       s->nest_count = 1;
-                       s->owner = proc;
-                       SCHED_ENQUEUE(proc);
-               }
-       }
-
-       proc_permit();
-}