incubator-nuttx/sched/sched/sched_get_stackinfo.c

107 lines
3.6 KiB
C

/****************************************************************************
* sched/sched/sched_get_stackinfo.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <assert.h>
#include "nuttx/sched.h"
#include "sched/sched.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxsched_get_stackinfo
*
* Description:
* Report information about a thread's stack allocation.
*
* Input Parameters:
* pid - Identifies the thread to query. Zero is interpreted as the
* the calling thread, -1 is interpreted as the calling task.
* stackinfo - User-provided location to return the stack information.
*
* Returned Value:
* Zero (OK) if successful. Otherwise, a negated errno value is returned.
*
* -ENOENT Returned if pid does not refer to an active task
* -EACCES The calling thread does not have privileges to access the
* stack of the thread associated with the pid.
*
****************************************************************************/
int nxsched_get_stackinfo(pid_t pid, FAR struct stackinfo_s *stackinfo)
{
FAR struct tcb_s *rtcb = this_task(); /* TCB of running task */
FAR struct tcb_s *qtcb; /* TCB of queried task */
DEBUGASSERT(rtcb != NULL && stackinfo != NULL);
/* Pid of 0 means that we are querying ourself */
if (pid == 0)
{
/* We can always query ourself */
qtcb = rtcb;
}
else
{
/* Get the task to be queried */
qtcb = nxsched_get_tcb(pid);
if (qtcb == NULL)
{
return -ENOENT;
}
/* A kernel thread can query any other thread. Application threads
* can only query application threads in the same task group.
*/
if ((rtcb->flags & TCB_FLAG_TTYPE_MASK) != TCB_FLAG_TTYPE_KERNEL)
{
/* It is an application thread. It is permitted to query
* only threads within the same task group. It is not permitted
* to peek into the stacks of either kernel threads or other
* applications tasks.
*/
if (rtcb->group != qtcb->group)
{
return -EACCES;
}
}
}
stackinfo->adj_stack_size = qtcb->adj_stack_size;
stackinfo->stack_alloc_ptr = qtcb->stack_alloc_ptr;
stackinfo->stack_base_ptr = qtcb->stack_base_ptr;
return OK;
}