1 files changed, 79 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/common/internal-signals.h b/libc/sysdeps/linux/common/internal-signals.h
new file mode 100644
index 000000000..65e8de34b
--- /dev/null
+++ b/libc/sysdeps/linux/common/internal-signals.h
@@ -0,0 +1,79 @@
+/* Copyright (C) 2014-2017 Free Software Foundation, Inc.
+
+   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 <signal.h>
+
+/* The signal used for asynchronous cancelation.  */
+#define SIGCANCEL       __SIGRTMIN
+
+/* Signal needed for the kernel-supported POSIX timer implementation.
+   We can reuse the cancellation signal since we can distinguish
+   cancellation from timer expirations.  */
+#define SIGTIMER        SIGCANCEL
+
+/* Signal used to implement the setuid et.al. functions.  */
+#define SIGSETXID       (__SIGRTMIN + 1)
+
+/* Return if sig is used internally.  */
+static inline int
+__is_internal_signal (int sig)
+{
+  return (sig == SIGCANCEL) || (sig == SIGTIMER) || (sig == SIGSETXID);
+}
+
+/* Remove internal signal from the mask.  */
+static inline void
+__clear_internal_signals (sigset_t *set)
+{
+  __sigdelset (set, SIGCANCEL);
+  __sigdelset (set, SIGTIMER);
+  __sigdelset (set, SIGSETXID);
+}
+
+#define SIGALL_SET \
+  ((__sigset_t) { .__val = {[0 ...  _SIGSET_NWORDS-1 ] =  -1 } })
+
+/* Block all signals, including internal ones.  */
+static inline int
+__libc_signal_block_all (sigset_t *set)
+{
+  INTERNAL_SYSCALL_DECL (err);
+  return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_BLOCK, &SIGALL_SET,
+			   set, _NSIG / 8);
+}
+
+/* Block all application signals (excluding internal ones).  */
+static inline int
+__libc_signal_block_app (sigset_t *set)
+{
+  sigset_t allset = SIGALL_SET;
+  __clear_internal_signals (&allset);
+  INTERNAL_SYSCALL_DECL (err);
+  return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_BLOCK, &allset, set,
+			   _NSIG / 8);
+}
+
+/* Restore current process signal mask.  */
+static inline int
+__libc_signal_restore_set (const sigset_t *set)
+{
+  INTERNAL_SYSCALL_DECL (err);
+  return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, set, NULL,
+			   _NSIG / 8);
+}
+
+/* Used to communicate with signal handler.  */
+extern struct xid_command *__xidcmd attribute_hidden;