1 // Copyright 2010 Google Inc.
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3 //
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5 // modification, are permitted provided that the following conditions are
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7 //
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10 // * Redistributions in binary form must reproduce the above copyright
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16 //
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27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
29 #include "utils/signals/misc.hpp"
30
31 #if defined(HAVE_CONFIG_H)
32 # include "config.h"
33 #endif
34
35 extern "C" {
36 #include <signal.h>
37 }
38
39 #include <cerrno>
40 #include <cstddef>
41
42 #include "utils/format/macros.hpp"
43 #include "utils/signals/exceptions.hpp"
44
45 namespace signals = utils::signals;
46
47
48 /// Number of the last valid signal.
49 const int utils::signals::last_signo = LAST_SIGNO;
50
51
52 /// Resets a signal handler to its default behavior.
53 ///
54 /// \param signo The number of the signal handler to reset.
55 ///
56 /// \throw signals::system_error If there is a problem trying to reset the
57 /// signal handler to its default behavior.
58 void
reset(const int signo)59 signals::reset(const int signo)
60 {
61 struct ::sigaction sa;
62 sa.sa_handler = SIG_DFL;
63 sigemptyset(&sa.sa_mask);
64 sa.sa_flags = 0;
65
66 if (::sigaction(signo, &sa, NULL) == -1) {
67 const int original_errno = errno;
68 throw system_error(F("Failed to reset signal %s") % signo,
69 original_errno);
70 }
71 }
72