rtems/src/signalcatch.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSImplClassicSignal
0007  *
0008  * @brief This source file contains the implementation of
0009  *   rtems_signal_catch() and the Signal Manager multiprocessing (MP) support
0010  *   system initialization.
0011  */
0012
0013 /*
0014  *  COPYRIGHT (c) 1989-1999.
0015  *  On-Line Applications Research Corporation (OAR).
0016  *
0017  * Redistribution and use in source and binary forms, with or without
0018  * modification, are permitted provided that the following conditions
0019  * are met:
0020  * 1. Redistributions of source code must retain the above copyright
0021  *    notice, this list of conditions and the following disclaimer.
0022  * 2. Redistributions in binary form must reproduce the above copyright
0023  *    notice, this list of conditions and the following disclaimer in the
0024  *    documentation and/or other materials provided with the distribution.
0025  *
0026  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0027  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0028  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0029  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0030  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0031  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0032  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0033  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0034  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0035  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0036  * POSSIBILITY OF SUCH DAMAGE.
0037  */
0038
0039 #ifdef HAVE_CONFIG_H
0040 #include "config.h"
0041 #endif
0042
0043 #include <rtems/rtems/signalimpl.h>
0044 #include <rtems/rtems/modesimpl.h>
0045 #include <rtems/rtems/tasksdata.h>
0046 #include <rtems/score/threadimpl.h>
0047
0048 RTEMS_STATIC_ASSERT( RTEMS_DEFAULT_MODES == 0, _ASR_Create_mode_set );
0049
0050 rtems_status_code rtems_signal_catch(
0051   rtems_asr_entry   asr_handler,
0052   rtems_mode        mode_set
0053 )
0054 {
0055   Thread_Control     *executing;
0056   RTEMS_API_Control  *api;
0057   ASR_Information    *asr;
0058   ISR_lock_Context    lock_context;
0059
0060 #if defined(RTEMS_SMP) || CPU_ENABLE_ROBUST_THREAD_DISPATCH == TRUE
0061   if (
0062     asr_handler != NULL &&
0063     !_Modes_Is_interrupt_level_supported( mode_set )
0064   ) {
0065     return RTEMS_NOT_IMPLEMENTED;
0066   }
0067 #endif
0068
0069   executing = _Thread_State_acquire_for_executing( &lock_context );
0070
0071 #if defined(RTEMS_SMP)
0072   if (
0073     asr_handler != NULL &&
0074     !_Modes_Is_preempt_mode_supported( mode_set, executing )
0075   ) {
0076     _Thread_State_release( executing, &lock_context );
0077     return RTEMS_NOT_IMPLEMENTED;
0078   }
0079 #endif
0080
0081   api = executing->API_Extensions[ THREAD_API_RTEMS ];
0082   asr = &api->Signal;
0083   asr->handler = asr_handler;
0084   asr->mode_set = mode_set;
0085
0086 #if defined(RTEMS_SMP)
0087   if ( asr_handler == NULL ) {
0088     Chain_Node *node;
0089
0090     /*
0091      * In SMP configurations, signals may be sent on other processors
0092      * (interrupts or threads) in parallel.  This will cause an inter-processor
0093      * interrupt which may be blocked by the above interrupt disable.
0094      */
0095
0096     node = &api->Signal_action.Node;
0097     _Assert( asr->signals_pending == 0 || !_Chain_Is_node_off_chain( node ) );
0098     _Assert( asr->signals_pending != 0 || _Chain_Is_node_off_chain( node ) );
0099
0100     if ( !_Chain_Is_node_off_chain( node ) ) {
0101       asr->signals_pending = 0;
0102       _Chain_Extract_unprotected( node );
0103       _Chain_Set_off_chain( node );
0104     }
0105   }
0106 #else
0107   /*
0108    * In uniprocessor configurations, as soon as interrupts are disabled above
0109    * nobody can send signals to the executing thread.  So, pending signals at
0110    * this point cannot appear.
0111    */
0112   _Assert( asr->signals_pending == 0 );
0113   _Assert( _Chain_Is_node_off_chain( &api->Signal_action.Node ) );
0114 #endif
0115
0116   _Thread_State_release( executing, &lock_context );
0117   return RTEMS_SUCCESSFUL;
0118 }