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-rw-r--r--linuxthreads/signals.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/linuxthreads/signals.c b/linuxthreads/signals.c
new file mode 100644
index 0000000000..905e11e5fe
--- /dev/null
+++ b/linuxthreads/signals.c
@@ -0,0 +1,148 @@
+/* Linuxthreads - a simple clone()-based implementation of Posix        */
+/* threads for Linux.                                                   */
+/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr)              */
+/*                                                                      */
+/* This program is free software; you can redistribute it and/or        */
+/* modify it under the terms of the GNU Library General Public License  */
+/* as published by the Free Software Foundation; either version 2       */
+/* of the License, or (at your option) any later version.               */
+/*                                                                      */
+/* This program is distributed in the hope that it will be useful,      */
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of       */
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        */
+/* GNU Library General Public License for more details.                 */
+
+/* Handling of signals */
+
+#include <errno.h>
+#include <signal.h>
+#include "pthread.h"
+#include "internals.h"
+#include "spinlock.h"
+
+int pthread_sigmask(int how, const sigset_t * newmask, sigset_t * oldmask)
+{
+  sigset_t mask;
+
+  if (newmask != NULL) {
+    mask = *newmask;
+    /* Don't allow PTHREAD_SIG_RESTART to be unmasked.
+       Don't allow PTHREAD_SIG_CANCEL to be masked. */
+    switch(how) {
+    case SIG_SETMASK:
+      sigaddset(&mask, PTHREAD_SIG_RESTART);
+      sigdelset(&mask, PTHREAD_SIG_CANCEL);
+      break;
+    case SIG_BLOCK:
+      sigdelset(&mask, PTHREAD_SIG_CANCEL);
+      break;
+    case SIG_UNBLOCK:
+      sigdelset(&mask, PTHREAD_SIG_RESTART);
+      break;
+    }
+    newmask = &mask;
+  }
+  if (sigprocmask(how, newmask, oldmask) == -1)
+    return errno;
+  else
+    return 0;
+}
+
+int pthread_kill(pthread_t thread, int signo)
+{
+  pthread_handle handle = thread_handle(thread);
+  int pid;
+
+  acquire(&handle->h_spinlock);
+  if (invalid_handle(handle, thread)) {
+    release(&handle->h_spinlock);
+    return ESRCH;
+  }
+  pid = handle->h_descr->p_pid;
+  release(&handle->h_spinlock);
+  if (kill(pid, signo) == -1)
+    return errno;
+  else
+    return 0;
+}
+
+/* The set of signals on which some thread is doing a sigwait */
+static sigset_t sigwaited;
+static pthread_mutex_t sigwaited_mut = PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t sigwaited_changed = PTHREAD_COND_INITIALIZER;
+
+int sigwait(const sigset_t * set, int * sig)
+{
+  volatile pthread_descr self = thread_self();
+  sigset_t mask;
+  int s;
+  struct sigaction action, saved_signals[NSIG];
+  sigjmp_buf jmpbuf;
+
+  pthread_mutex_lock(&sigwaited_mut);
+  /* Make sure no other thread is waiting on our signals */
+test_again:
+  for (s = 1; s < NSIG; s++) {
+    if (sigismember(set, s) && sigismember(&sigwaited, s)) {
+      pthread_cond_wait(&sigwaited_changed, &sigwaited_mut);
+      goto test_again;
+    }
+  }
+  /* Get ready to block all signals except those in set
+     and the cancellation signal */
+  sigfillset(&mask);
+  sigdelset(&mask, PTHREAD_SIG_CANCEL);
+  /* Signals in set are assumed blocked on entrance */
+  /* Install our signal handler on all signals in set,
+     and unblock them in mask.
+     Also mark those signals as being sigwaited on */
+  for (s = 1; s < NSIG; s++) {
+    if (sigismember(set, s) && s != PTHREAD_SIG_CANCEL) {
+      sigdelset(&mask, s);
+      action.sa_handler = __pthread_sighandler;
+      sigemptyset(&action.sa_mask);
+      action.sa_flags = 0;
+      sigaction(s, &action, &(saved_signals[s]));
+      sigaddset(&sigwaited, s);
+    }
+  }
+  pthread_mutex_unlock(&sigwaited_mut);
+
+  /* Test for cancellation */
+  if (sigsetjmp(jmpbuf, 1) == 0) {
+    self->p_cancel_jmp = &jmpbuf;
+    if (! (self->p_canceled && self->p_cancelstate == PTHREAD_CANCEL_ENABLE)) {
+      /* Reset the signal count */
+      self->p_signal = 0;
+      /* Unblock the signals and wait for them */
+      sigsuspend(&mask);
+    }
+  }
+  self->p_cancel_jmp = NULL;
+  /* The signals are now reblocked. Restore the sighandlers. */
+  pthread_mutex_lock(&sigwaited_mut);
+  for (s = 1; s < NSIG; s++) {
+    if (sigismember(set, s) && s != PTHREAD_SIG_CANCEL) {
+      sigaction(s, &(saved_signals[s]), NULL);
+      sigdelset(&sigwaited, s);
+    }
+  }
+  pthread_cond_broadcast(&sigwaited_changed);
+  pthread_mutex_unlock(&sigwaited_mut);
+  /* Check for cancellation */
+  pthread_testcancel();
+  /* We should have self->p_signal != 0 and equal to the signal received */
+  *sig = self->p_signal;
+  return 0;
+}
+
+int raise (int sig)
+{
+  int retcode = pthread_kill(pthread_self(), sig);
+  if (retcode == 0)
+    return 0;
+  else {
+    errno = retcode;
+    return -1;
+  }
+}