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Diffstat (limited to 'nuttx/sched/pause.c')
-rw-r--r-- | nuttx/sched/pause.c | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/nuttx/sched/pause.c b/nuttx/sched/pause.c new file mode 100644 index 000000000..607c4c775 --- /dev/null +++ b/nuttx/sched/pause.c @@ -0,0 +1,110 @@ +/**************************************************************************** + * 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); +} |