px4-firmware/nuttx/sched/sig_allocatependingsigaction.c

138 lines
4.6 KiB
C

/************************************************************************
* sched/sig_allocatependingsigaction.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 <signal.h>
#include <assert.h>
#include <nuttx/arch.h>
#include "os_internal.h"
#include "sig_internal.h"
/************************************************************************
* Definitions
************************************************************************/
/************************************************************************
* Private Type Declarations
************************************************************************/
/************************************************************************
* Global Variables
************************************************************************/
/************************************************************************
* Private Variables
************************************************************************/
/************************************************************************
* Private Function Prototypes
************************************************************************/
/************************************************************************
* Public Functions
************************************************************************/
/************************************************************************
* Name: sig_allocatependingsigaction
*
* Description:
* Allocate a new element for the pending signal action queue
*
************************************************************************/
FAR sigq_t *sig_allocatependingsigaction(void)
{
FAR sigq_t *sigq;
irqstate_t saved_state;
/* Check if we were called from an interrupt handler. */
if (up_interrupt_context())
{
/* Try to get the pending signal action structure from the free list */
sigq = (FAR sigq_t*)sq_remfirst(&g_sigpendingaction);
/* If so, then try the special list of structures reserved for
* interrupt handlers
*/
if (!sigq)
{
sigq = (FAR sigq_t*)sq_remfirst(&g_sigpendingirqaction);
}
}
/* If we were not called from an interrupt handler, then we are
* free to allocate pending signal action structures if necessary. */
else
{
/* Try to get the pending signal action structure from the free list */
saved_state = irqsave();
sigq = (FAR sigq_t*)sq_remfirst(&g_sigpendingaction);
irqrestore(saved_state);
/* Check if we got one. */
if (!sigq)
{
/* No...Try the resource pool */
if (!sigq)
{
sigq = (FAR sigq_t *)kmalloc((sizeof (sigq_t)));
}
/* Check if we got an allocated message */
if (sigq)
{
sigq->type = SIG_ALLOC_DYN;
}
}
}
return sigq;
}