| /**************************************************************************** |
| * sched/pause.c |
| * |
| * Copyright (C) 2012 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 <unistd.h> |
| #include <signal.h> |
| |
| /**************************************************************************** |
| * Preprocessor Definitions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Private Type Definitions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Global Variables |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Private Variables |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Private Function Prototypes |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Public Functions |
| ****************************************************************************/ |
| |
| /**************************************************************************** |
| * Name: pause |
| * |
| * Description: |
| * The pause() function will suspend the calling thread until delivery of a |
| * non-blocked signal. |
| * |
| * Input Parameters: |
| * None |
| * |
| * Returned Value: |
| * Since pause() suspends thread execution indefinitely unless interrupted |
| * a signal, there is no successful completion return value. A value of -1 |
| * will always be returned and errno set to indicate the error (EINTR). |
| * |
| * POSIX compatibility: |
| * In the POSIX description of this function is the pause() function will |
| * suspend the calling thread until delivery of a signal whose action is |
| * either to execute a signal-catching function or to terminate the |
| * process. This implementation only waits for any non-blocked signal |
| * to be received. |
| * |
| ****************************************************************************/ |
| |
| int pause(void) |
| { |
| sigset_t set; |
| struct siginfo value; |
| |
| /* Set up for the sleep. Using the empty set means that we are not |
| * waiting for any particular signal. However, any unmasked signal |
| * can still awaken sigtimedwait(). |
| */ |
| |
| (void)sigemptyset(&set); |
| |
| /* sigtwaitinfo() cannot succeed. It should always return error EINTR |
| * meaning that some unblocked signal was caught. |
| */ |
| |
| return sigwaitinfo(&set, &value); |
| } |