1 files changed, 117 insertions, 0 deletions
diff --git a/nuttx/sched/work_cancel.c b/nuttx/sched/work_cancel.c
new file mode 100644
index 000000000..c277f024d
--- /dev/null
+++ b/nuttx/sched/work_cancel.c
@@ -0,0 +1,117 @@
+/****************************************************************************
+ * sched/work_cancel.c
+ *
+ *   Copyright (C) 2009-2010 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 <queue.h>
+#include <assert.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/arch.h>
+#include <nuttx/wqueue.h>
+
+#include "work_internal.h"
+
+#ifdef CONFIG_SCHED_WORKQUEUE
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+/****************************************************************************
+ * Name: work_cancel
+ *
+ * Description:
+ *   Cancel previously queued work.  This removes work from the work queue.
+ *   After work has been canceled, it may be re-queue by calling work_queue()
+ *   again.
+ *
+ * Input parameters:
+ *   work   - The previously queue work structure to cancel
+ *
+ * Returned Value:
+ *   Zero on success, a negated errno on failure
+ *
+ ****************************************************************************/
+
+int work_cancel(struct work_s *work)
+{
+  irqstate_t flags;
+
+  DEBUGASSERT(work != NULL);
+
+  /* Cancelling the work is simply a matter of removing the work structure
+   * from the work queue.  This must be done with interrupts disabled because
+   * new work is typically added to the work queue from interrupt handlers.
+   */
+
+  flags = irqsave();
+  if (work->worker != NULL)
+    {
+      DEBUGASSERT(work->dq.flink || (FAR dq_entry_t *)work == g_work.head);
+      DEBUGASSERT(work->dq.blink || (FAR dq_entry_t *)work == g_work.tail);
+      dq_rem((FAR dq_entry_t *)work, &g_work);
+
+      work->worker = NULL;
+    }
+
+  irqrestore(flags);
+  return OK;
+}
+#endif /* CONFIG_SCHED_WORKQUEUE */