* libs/libc/signal/sig_altstack.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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 <signal.h>
#include <errno.h>
#include <string.h>
* Public Functions
****************************************************************************/
* Name: sigaltstack
*
* Description:
* The sigaltstack() function allows a process to define and examine the
* state of an alternate stack for signal handlers for the current thread.
* Signals that have been explicitly declared to execute on the alternate
* stack shall be delivered on the alternate stack.
*
****************************************************************************/
int sigaltstack(FAR const stack_t *ss, FAR stack_t *oss)
{
if (ss)
{
if (ss->ss_flags & SS_DISABLE)
{
goto out;
}
if (ss->ss_size < MINSIGSTKSZ)
{
set_errno(ENOMEM);
return ERROR;
}
set_errno(EINVAL);
return ERROR;
}
out:
if (oss)
{
memset(oss, 0, sizeof(*oss));
oss->ss_flags = SS_DISABLE;
}
return OK;
}