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+// Copyright 2010 The Kyua Authors.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * 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.
+// * Neither the name of Google Inc. 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.
+
+#include "utils/signals/misc.hpp"
+
+#if defined(HAVE_CONFIG_H)
+# include "config.h"
+#endif
+
+extern "C" {
+#include <signal.h>
+}
+
+#include <cerrno>
+#include <cstddef>
+
+#include "utils/format/macros.hpp"
+#include "utils/logging/macros.hpp"
+#include "utils/signals/exceptions.hpp"
+
+namespace signals = utils::signals;
+
+
+/// Number of the last valid signal.
+const int utils::signals::last_signo = LAST_SIGNO;
+
+
+/// Resets a signal handler to its default behavior.
+///
+/// \param signo The number of the signal handler to reset.
+///
+/// \throw signals::system_error If there is a problem trying to reset the
+/// signal handler to its default behavior.
+void
+signals::reset(const int signo)
+{
+ struct ::sigaction sa;
+ sa.sa_handler = SIG_DFL;
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = 0;
+
+ if (::sigaction(signo, &sa, NULL) == -1) {
+ const int original_errno = errno;
+ throw system_error(F("Failed to reset signal %s") % signo,
+ original_errno);
+ }
+}
+
+
+/// Resets all signals to their default handlers.
+///
+/// \return True if all signals could be reset properly; false otherwise.
+bool
+signals::reset_all(void)
+{
+ bool ok = true;
+
+ for (int signo = 1; signo <= signals::last_signo; ++signo) {
+ if (signo == SIGKILL || signo == SIGSTOP) {
+ // Don't attempt to reset immutable signals.
+ } else {
+ try {
+ signals::reset(signo);
+ } catch (const signals::error& e) {
+#if defined(SIGTHR)
+ if (signo == SIGTHR) {
+ // If FreeBSD's libthr is loaded, it prevents us from
+ // modifying SIGTHR (at least in 11.0-CURRENT as of
+ // 2015-01-28). Skip failures for this signal if they
+ // happen to avoid this corner case.
+ continue;
+ }
+#endif
+ LW(e.what());
+ ok = false;
+ }
+ }
+ }
+
+ return ok;
+}