1 files changed, 76 insertions, 0 deletions
diff --git a/sysdeps/pthread/raise.c b/sysdeps/pthread/raise.c
new file mode 100644
index 0000000000..583cd1535d
--- /dev/null
+++ b/sysdeps/pthread/raise.c
@@ -0,0 +1,76 @@
+/* ISO C raise function for libpthread.
+   Copyright (C) 2002-2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <pthread.h>
+#include <signal.h>
+#include <internal-signals.h>
+
+/* Raise the signal SIG.  POSIX requires raise to be async-signal-safe,
+   but also requires it to be equivalent to pthread_kill (pthread_self (), sig),
+   and that construct is *not* async-signal safe.  In particular, an
+   async signal handler that calls fork (which is also async-signal-safe)
+   could invalidate the handle returned by pthread_self, and/or cause
+   pthread_kill to be called twice.  So we must block signals around
+   the operation.  See bug 15368 for more detail.
+
+   Also, raise sets errno on failure, whereas pthread_kill returns the
+   error code.  (It is not possible for pthread_self to fail.)  */
+
+int
+__libc_raise (int sig)
+{
+  /* Disallow sending the signals we use for cancellation, timers,
+     setxid, etc.  This check is also performed in pthread_kill, but
+     if we do it now we can avoid blocking and then unblocking signals
+     unnecessarily.  */
+  if (__glibc_unlikely (__is_internal_signal (sig)))
+    {
+      __set_errno (EINVAL);
+      return -1;
+    }
+
+  /* We can safely assume that __libc_signal_block_app and
+     __libc_signal_restore_set will not fail, because
+     sigprocmask can only fail under three circumstances:
+
+     1. sigsetsize != sizeof (sigset_t) (EINVAL)
+     2. a failure in copy from/to user space (EFAULT)
+     3. an invalid 'how' operation (EINVAL)
+
+     Getting any of these would indicate a bug in either the
+     definition of sigset_t or the implementations of the
+     wrappers.  */
+  sigset_t omask;
+  __libc_signal_block_app (&omask);
+
+  int ret = __pthread_kill (__pthread_self (), sig);
+
+  __libc_signal_restore_set (&omask);
+
+  if (__glibc_unlikely (ret))
+    {
+      __set_errno (ret);
+      return -1;
+    }
+  return 0;
+}
+strong_alias (__libc_raise, raise)
+libc_hidden_def (raise)
+weak_alias (__libc_raise, gsignal)