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Diffstat (limited to 'lib/libpthread/thread/thr_kill.c')
| -rw-r--r-- | lib/libpthread/thread/thr_kill.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/lib/libpthread/thread/thr_kill.c b/lib/libpthread/thread/thr_kill.c new file mode 100644 index 0000000..6b25550 --- /dev/null +++ b/lib/libpthread/thread/thr_kill.c @@ -0,0 +1,166 @@ +/* + * Copyright (c) 1997 John Birrell <jb@cimlogic.com.au>. + * All rights reserved. + * + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by John Birrell. + * 4. Neither the name of the author nor the names of any co-contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL 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 AUTHOR 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. + * + * $FreeBSD$ + */ +#include <errno.h> +#include <signal.h> +#ifdef _THREAD_SAFE +#include <pthread.h> +#include "pthread_private.h" + +int +pthread_kill(pthread_t pthread, int sig) +{ + int ret; + + /* Check for invalid signal numbers: */ + if (sig < 0 || sig >= NSIG) + /* Invalid signal: */ + ret = EINVAL; + + /* + * Ensure the thread is in the list of active threads, and the + * signal is valid (signal 0 specifies error checking only) and + * not being ignored: + */ + else if (((ret = _find_thread(pthread)) == 0) && (sig > 0) && + (_thread_sigact[sig - 1].sa_handler != SIG_IGN)) { + /* + * Defer signals to protect the scheduling queues from + * access by the signal handler: + */ + _thread_kern_sig_defer(); + + switch (pthread->state) { + case PS_SIGSUSPEND: + /* + * Only wake up the thread if the signal is unblocked + * and there is a handler installed for the signal. + */ + if (!sigismember(&pthread->sigmask, sig) && + _thread_sigact[sig - 1].sa_handler != SIG_DFL) { + /* Change the state of the thread to run: */ + PTHREAD_NEW_STATE(pthread,PS_RUNNING); + + /* Return the signal number: */ + pthread->signo = sig; + } + /* Increment the pending signal count: */ + sigaddset(&pthread->sigpend,sig); + break; + + case PS_SIGWAIT: + /* Wake up the thread if the signal is blocked. */ + if (sigismember(pthread->data.sigwait, sig)) { + /* Change the state of the thread to run: */ + PTHREAD_NEW_STATE(pthread,PS_RUNNING); + + /* Return the signal number: */ + pthread->signo = sig; + } else + /* Increment the pending signal count. */ + sigaddset(&pthread->sigpend,sig); + break; + + case PS_FDR_WAIT: + case PS_FDW_WAIT: + case PS_POLL_WAIT: + case PS_SLEEP_WAIT: + case PS_SELECT_WAIT: + if (!sigismember(&pthread->sigmask, sig) && + (_thread_sigact[sig - 1].sa_handler != SIG_IGN)) { + /* Flag the operation as interrupted: */ + pthread->interrupted = 1; + + if (pthread->flags & PTHREAD_FLAGS_IN_WORKQ) + PTHREAD_WORKQ_REMOVE(pthread); + + /* Change the state of the thread to run: */ + PTHREAD_NEW_STATE(pthread,PS_RUNNING); + + /* Return the signal number: */ + pthread->signo = sig; + } else { + /* Increment the pending signal count: */ + sigaddset(&pthread->sigpend,sig); + } + break; + + default: + /* Increment the pending signal count: */ + sigaddset(&pthread->sigpend,sig); + break; + } + + + /* + * Check that a custom handler is installed + * and if the signal is not blocked: + */ + if (_thread_sigact[sig - 1].sa_handler != SIG_DFL && + _thread_sigact[sig - 1].sa_handler != SIG_IGN && + sigismember(&pthread->sigpend, sig) && + !sigismember(&pthread->sigmask, sig)) { + pthread_t pthread_saved = _thread_run; + + /* Current thread inside critical region? */ + if (_thread_run->sig_defer_count > 0) + pthread->sig_defer_count++; + + _thread_run = pthread; + + /* Clear the pending signal: */ + sigdelset(&pthread->sigpend, sig); + + /* + * Dispatch the signal via the custom signal + * handler: + */ + (*(_thread_sigact[sig - 1].sa_handler))(sig); + + _thread_run = pthread_saved; + + if (_thread_run->sig_defer_count > 0) + pthread->sig_defer_count--; + } + + /* + * Undefer and handle pending signals, yielding if + * necessary: + */ + _thread_kern_sig_undefer(); + } + + /* Return the completion status: */ + return (ret); +} +#endif |
