aboutsummaryrefslogtreecommitdiff
path: root/nuttx/sched/sched_getparam.c
diff options
context:
space:
mode:
Diffstat (limited to 'nuttx/sched/sched_getparam.c')
-rw-r--r--nuttx/sched/sched_getparam.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/nuttx/sched/sched_getparam.c b/nuttx/sched/sched_getparam.c
new file mode 100644
index 000000000..47eab4988
--- /dev/null
+++ b/nuttx/sched/sched_getparam.c
@@ -0,0 +1,146 @@
+/************************************************************************
+ * sched/sched_getparam.c
+ *
+ * Copyright (C) 2007, 2009 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 <sys/types.h>
+#include <sched.h>
+
+#include "os_internal.h"
+
+/************************************************************************
+ * Definitions
+ ************************************************************************/
+
+/************************************************************************
+ * Private Type Declarations
+ ************************************************************************/
+
+/************************************************************************
+ * Global Variables
+ ************************************************************************/
+
+/************************************************************************
+ * Private Variables
+ ************************************************************************/
+
+/************************************************************************
+ * Private Function Prototypes
+ ************************************************************************/
+
+/************************************************************************
+ * Private Functions
+ ************************************************************************/
+
+/************************************************************************
+ * Public Functions
+ ************************************************************************/
+
+/************************************************************************
+ * Name: sched_getparam
+ *
+ * Description:
+ * This function gets the scheduling priority of the task
+ * specified by pid.
+ *
+ * Inputs:
+ * pid - the task ID of the task. If pid is zero, the priority
+ * of the calling task is returned.
+ * param - A structure whose member sched_priority is the integer
+ * priority. The task's priority is copied to the sched_priority
+ * element of this structure.
+ *
+ * Return Value:
+ * 0 (OK) if successful, otherwise -1 (ERROR).
+ *
+ * This function can fail if param is null or if pid does
+ * not correspond to any task.
+ *
+ * Assumptions:
+ *
+ ************************************************************************/
+
+int sched_getparam (pid_t pid, struct sched_param * param)
+{
+ FAR _TCB *rtcb;
+ FAR _TCB *tcb;
+ int ret = OK;
+
+ if (!param)
+ {
+ return ERROR;
+ }
+
+ /* Check if the task to restart is the calling task */
+
+ rtcb = (FAR _TCB*)g_readytorun.head;
+ if ((pid == 0) || (pid == rtcb->pid))
+ {
+ /* Return the priority if the calling task. */
+
+ param->sched_priority = (int)rtcb->sched_priority;
+ }
+
+ /* Ths pid is not for the calling task, we will have to look it up */
+
+ else
+ {
+ /* Get the TCB associated with this pid */
+
+ sched_lock();
+ tcb = sched_gettcb(pid);
+ if (!tcb)
+ {
+ /* This pid does not correspond to any known task */
+
+ ret = ERROR;
+ }
+ else
+ {
+ /* Return the priority of the task */
+
+ param->sched_priority = (int)tcb->sched_priority;
+ }
+
+ sched_unlock();
+ }
+
+ return ret;
+}
+