external/bsd/kyua-cli/dist/utils/signals/misc.cpp

   1 // Copyright 2010 Google Inc.
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  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
  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 }