external/bsd/atf/dist/tools/signals.cpp

   1 //
   2 // Automated Testing Framework (atf)
   3 //
   4 // Copyright (c) 2007 The NetBSD Foundation, Inc.
   5 // All rights reserved.
   6 //
   7 // Redistribution and use in source and binary forms, with or without
   8 // modification, are permitted provided that the following conditions
   9 // are met:
  10 // 1. Redistributions of source code must retain the above copyright
  11 //    notice, this list of conditions and the following disclaimer.
  12 // 2. Redistributions in binary form must reproduce the above copyright
  13 //    notice, this list of conditions and the following disclaimer in the
  14 //    documentation and/or other materials provided with the distribution.
  15 //
  16 // THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND
  17 // CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  18 // INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  19 // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20 // IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY
  21 // DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  23 // GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  25 // IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  26 // OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  27 // IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28 //
  29
  30 extern "C" {
  31 #include <signal.h>
  32 #include <unistd.h>
  33 }
  34
  35 #include <cerrno>
  36 #include <cstdlib>
  37
  38 #include "exceptions.hpp"
  39 #include "signals.hpp"
  40
  41 namespace impl = tools::signals;
  42 #define IMPL_NAME "tools::signals"
  43
  44 #define LAST_SIGNO 63
  45 const int impl::last_signo = LAST_SIGNO;
  46
  47 // ------------------------------------------------------------------------
  48 // The "signal_holder" class.
  49 // ------------------------------------------------------------------------
  50
  51 namespace {
  52
  53 static bool happened[LAST_SIGNO + 1];
  54
  55 static
  56 void
  57 holder_handler(const int signo)
  58 {
  59     happened[signo] = true;
  60 }
  61
  62 } // anonymous namespace
  63
  64 impl::signal_holder::signal_holder(const int signo) :
  65     m_signo(signo),
  66     m_sp(NULL)
  67 {
  68     happened[signo] = false;
  69     m_sp = new signal_programmer(m_signo, holder_handler);
  70 }
  71
  72 impl::signal_holder::~signal_holder(void)
  73 {
  74     if (m_sp != NULL)
  75         delete m_sp;
  76
  77     if (happened[m_signo])
  78         ::kill(::getpid(), m_signo);
  79 }
  80
  81 void
  82 impl::signal_holder::process(void)
  83 {
  84     if (happened[m_signo]) {
  85         delete m_sp;
  86         m_sp = NULL;
  87         happened[m_signo] = false;
  88         ::kill(::getpid(), m_signo);
  89         m_sp = new signal_programmer(m_signo, holder_handler);
  90     }
  91 }
  92
  93 // ------------------------------------------------------------------------
  94 // The "signal_programmer" class.
  95 // ------------------------------------------------------------------------
  96
  97 impl::signal_programmer::signal_programmer(const int signo, const handler h) :
  98     m_signo(signo),
  99     m_handler(h),
 100     m_programmed(false)
 101 {
 102     struct ::sigaction sa;
 103
 104     sa.sa_handler = m_handler;
 105     sigemptyset(&sa.sa_mask);
 106     sa.sa_flags = 0;
 107
 108     if (::sigaction(m_signo, &sa, &m_oldsa) == -1)
 109         throw tools::system_error(IMPL_NAME, "Could not install handler for "
 110                                 "signal", errno);
 111     m_programmed = true;
 112 }
 113
 114 impl::signal_programmer::~signal_programmer(void)
 115 {
 116     unprogram();
 117 }
 118
 119 void
 120 impl::signal_programmer::unprogram(void)
 121 {
 122     if (m_programmed) {
 123         if (::sigaction(m_signo, &m_oldsa, NULL) == -1)
 124             std::abort();
 125         m_programmed = false;
 126     }
 127 }
 128
 129 // ------------------------------------------------------------------------
 130 // Free functions.
 131 // ------------------------------------------------------------------------
 132
 133 void
 134 impl::reset(const int signo)
 135 {
 136     struct ::sigaction sa;
 137
 138     sa.sa_handler = SIG_DFL;
 139     sigemptyset(&sa.sa_mask);
 140     sa.sa_flags = 0;
 141
 142     (void)::sigaction(signo, &sa, NULL);
 143 }