NuttX RTOS

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 154 insertions, 0 deletions

diff --git a/nuttx/sched/wd_cancel.c b/nuttx/sched/wd_cancel.c
new file mode 100644
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+/************************************************************
+ * wd_cancel.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * 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 Gregory Nutt 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 <sys/types.h>
+#include <assert.h>
+#include <wdog.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+#include "wd_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Type Declarations
+ ************************************************************/
+
+/************************************************************
+ * Global Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Function:  wd_cancel
+ *
+ * Description:
+ * This function cancels a currently running watchdog timer.
+ * Watchdog timers may be canceled from the interrupt level.
+ *
+ * Parameters:
+ *   wdid - ID of the watchdog to cancel.
+ *
+ * Return Value:
+ *   OK or ERROR
+ *
+ * Assumptions:
+ *
+ ************************************************************/
+
+STATUS wd_cancel (WDOG_ID wdid)
+{
+  wdog_t *curr;
+  wdog_t *prev;
+  uint32  saved_state;
+  STATUS  ret = ERROR;
+
+  /* Prohibit timer interactions with the timer queue until the
+   * cancellation is complete
+   */
+
+  saved_state = irqsave();
+
+  /* Make sure that the the watchdog is still active */
+
+  if (wdid->active)
+    {
+      /* Search the g_wdactivelist for the target FCB.  We can't use sq_rem
+       * to do this because there are additional operations that need to be
+       * done.
+       */
+
+      prev = NULL;
+      curr = (wdog_t*)g_wdactivelist.head;
+
+      while((curr) && (curr != wdid))
+        {
+          prev = curr;
+          curr = curr->next;
+        }
+
+      /* Check if the watchdog was found in the list.  If not, then an OS
+       * error has occurred because the watchdog is marked active!
+       */
+
+      if (!curr)
+        {
+          PANIC(OSERR_WDOGNOTFOUND);
+        }
+      else
+        {
+          /* If there is a watchdog in the timer queue after the one that
+           * is being canceled, then it inherits the remaining ticks.
+           */
+
+          if (curr->next) curr->next->lag += curr->lag;
+
+          /* Now, remove the watchdog from the timer queue */
+
+          if (prev)
+            (void)sq_remafter((sq_entry_t*)prev, &g_wdactivelist);
+          else
+            (void)sq_remfirst(&g_wdactivelist);
+          wdid->next = NULL;
+
+          /* If we made it this far, then we were successful */
+
+          ret = OK;
+        }
+
+      /* Mark the watchdog inactive */
+
+      wdid->active = FALSE;
+    }
+  irqrestore(saved_state);
+  return ret;
+}