[3405] Moved SignalSet class to util from util:io.

6 files changed, 1 insertions, 660 deletions

diff --git a/src/lib/util/io/Makefile.am b/src/lib/util/io/Makefile.am
index c0fae76b1f..8a1522d734 100644
--- a/src/lib/util/io/Makefile.am
+++ b/src/lib/util/io/Makefile.am
@@ -1,4 +1,4 @@
-SUBDIRS = . tests
+SUBDIRS = .
 AM_CXXFLAGS = $(B10_CXXFLAGS)
 
 AM_CPPFLAGS = -I$(top_srcdir)/src/lib -I$(top_builddir)/src/lib
@@ -7,7 +7,6 @@ AM_CPPFLAGS += $(BOOST_INCLUDES)
 lib_LTLIBRARIES = libkea-util-io.la
 libkea_util_io_la_SOURCES = fd.h fd.cc fd_share.h fd_share.cc
 libkea_util_io_la_SOURCES += socketsession.h socketsession.cc sockaddr_util.h
-libkea_util_io_la_SOURCES += signal_set.cc signal_set.h
 libkea_util_io_la_SOURCES += pktinfo_utilities.h
 libkea_util_io_la_LIBADD = $(top_builddir)/src/lib/exceptions/libkea-exceptions.la
 
diff --git a/src/lib/util/io/signal_set.cc b/src/lib/util/io/signal_set.cc
deleted file mode 100644
index b187df69d1..0000000000
--- a/src/lib/util/io/signal_set.cc
+++ /dev/null
@@ -1,227 +0,0 @@
-// Copyright (C) 2014 Internet Systems Consortium, Inc. ("ISC")
-//
-// Permission to use, copy, modify, and/or distribute this software for any
-// purpose with or without fee is hereby granted, provided that the above
-// copyright notice and this permission notice appear in all copies.
-//
-// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
-// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
-// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
-// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
-// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
-// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
-// PERFORMANCE OF THIS SOFTWARE.
-
-#include <util/io/signal_set.h>
-
-#include <cerrno>
-#include <list>
-
-using namespace isc;
-using namespace isc::util::io;
-
-namespace {
-
-/// @brief Returns a pointer to the global set of registered signals.
-///
-/// Multiple instances of @c SignalSet may use this pointer to access
-/// and update the set.
-///
-/// @return Pointer to the global set of registered signals. This pointer
-/// is always initialized and points to a valid object.
-std::set<int>* getRegisteredSignals() {
-    static std::set<int> registered_signals;
-    return (&registered_signals);
-}
-
-/// @brief Returns a pointer to static collection of signals received.
-///
-/// Multiple instances of @c SignalSet may use this pointer to access
-/// and update the queue of signals received.
-///
-/// @return Static collection of signals received. This pointer is always
-/// initialized and points to a valid object.
-std::list<int>* getSignalStates() {
-    static std::list<int> states;
-    return (&states);
-}
-
-/// @brief Internal signal handler for @c isc::util::io::SignalSet class.
-///
-/// This signal handler adds a signal number for which it is being
-/// invoked to the queue of received signals. It prevents adding duplicated
-/// signals. All duplicated signals are dropped. This prevents hammering
-/// a process to invoke handlers (e.g. DHCP server reconfiguration), when
-/// many the same signals are received one after another.
-///
-/// @param sig Signal number.
-void internalHandler(int sig) {
-    std::list<int>* states = getSignalStates();
-    for (std::list<int>::const_iterator it = states->begin();
-         it != states->end(); ++it) {
-        if (sig == *it) {
-            return;
-        }
-    }
-    states->push_back(sig);
-}
-
-}
-
-namespace isc {
-namespace util {
-namespace io {
-
-SignalSet::SignalSet(const int sig0) {
-    add(sig0);
-}
-
-SignalSet::SignalSet(const int sig0, const int sig1) {
-    add(sig0);
-    add(sig1);
-}
-
-SignalSet::SignalSet(const int sig0, const int sig1, const int sig2) {
-    add(sig0);
-    add(sig1);
-    add(sig2);
-}
-
-SignalSet::~SignalSet() {
-    // Set default signal handlers.
-    try {
-        clear();
-    } catch (...) {
-        // Not a good thing to throw from a destructor. in fact this should
-        // not throw an exception because we just unregister the signals
-        // that we have previously registered. So the signal codes are fine.
-    }
-}
-
-void
-SignalSet::add(const int sig) {
-    insert(sig);
-    struct sigaction sa;
-    sa.sa_handler = internalHandler;
-    if (sigaction(sig, &sa, 0) < 0) {
-        erase(sig);
-        isc_throw(SignalSetError, "failed to register a signal handler for"
-                  " signal " << sig << ": " << strerror(errno));
-    }
-}
-
-void
-SignalSet::clear() {
-    // Iterate over a copy of the registered signal set because the
-    // remove function is erasing the elements and we don't want to
-    // erase the elements we are iterating over. This would cause
-    // a segfault.
-    std::set<int> all_signals = local_signals_;
-    for (std::set<int>::const_iterator it = all_signals.begin();
-         it != all_signals.end(); ++it) {
-        remove(*it);
-    }
-}
-
-int
-SignalSet::getNext() const {
-    std::list<int>* states = getSignalStates();
-    for (std::list<int>::iterator it = states->begin();
-         it != states->end(); ++it) {
-        if (local_signals_.find(*it) != local_signals_.end()) {
-            return (*it);
-        }
-    }
-    return (-1);
-}
-
-void
-SignalSet::erase(const int sig) {
-    if (local_signals_.find(sig) == local_signals_.end()) {
-        isc_throw(SignalSetError, "failed to unregister signal " << sig
-                  << " from a signal set: signal is not owned by the"
-                  " signal set");
-    }
-    // Remove globally registered signal.
-    getRegisteredSignals()->erase(sig);
-    // Remove unhandled signals from the queue.
-    for (std::list<int>::iterator it = getSignalStates()->begin();
-         it != getSignalStates()->end(); ++it) {
-        if (*it == sig) {
-            it = getSignalStates()->erase(it);
-        }
-    }
-    // Remove locally registered signal.
-    local_signals_.erase(sig);
-}
-
-void
-SignalSet::handleNext(SignalHandler signal_handler) {
-    block();
-    int signum = getNext();
-    if (signum >= 0) {
-        popNext();
-        try {
-            signal_handler(signum);
-        } catch (...) {
-            unblock();
-            throw;
-        }
-    }
-    unblock();
-}
-
-void
-SignalSet::insert(const int sig) {
-    std::set<int>* global_signals = getRegisteredSignals();
-    if ((global_signals->find(sig) != global_signals->end()) ||
-        (local_signals_.find(sig) != local_signals_.end())) {
-        isc_throw(SignalSetError, "attempt to register a duplicate signal "
-                  << sig);
-    }
-    global_signals->insert(sig);
-    local_signals_.insert(sig);
-}
-
-void
-SignalSet::maskSignals(const int mask) const {
-    sigset_t new_set;
-    for (std::set<int>::const_iterator it = getRegisteredSignals()->begin();
-         it != getRegisteredSignals()->end(); ++it) {
-        sigaddset(&new_set, *it);
-    }
-    sigprocmask(mask, &new_set, 0);
-}
-
-void
-SignalSet::popNext() {
-    std::list<int>* states = getSignalStates();
-    for (std::list<int>::iterator it = states->begin();
-         it != states->end(); ++it) {
-        if (local_signals_.find(*it) != local_signals_.end()) {
-            states->erase(it);
-            return;
-        }
-    }
-}
-
-void
-SignalSet::remove(const int sig) {
-    // Unregister only if we own this signal.
-    if (local_signals_.find(sig) != local_signals_.end()) {
-        struct sigaction sa;
-        sa.sa_handler = SIG_DFL;
-        if (sigaction(sig, &sa, 0) < 0) {
-            isc_throw(SignalSetError, "unable to restore original signal"
-                      " handler for signal: " << sig);
-        }
-        erase(sig);
-    } else {
-        isc_throw(SignalSetError, "failed to unregister signal " << sig
-                  << ": this signal is not owned by the signal set");
-    }
-}
-
-} // end of isc::util::io
-} // end of isc::util
-} // end of isc
diff --git a/src/lib/util/io/signal_set.h b/src/lib/util/io/signal_set.h
deleted file mode 100644
index 5d52559568..0000000000
--- a/src/lib/util/io/signal_set.h
+++ /dev/null
@@ -1,189 +0,0 @@
-// Copyright (C) 2014 Internet Systems Consortium, Inc. ("ISC")
-//
-// Permission to use, copy, modify, and/or distribute this software for any
-// purpose with or without fee is hereby granted, provided that the above
-// copyright notice and this permission notice appear in all copies.
-//
-// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
-// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
-// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
-// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
-// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
-// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
-// PERFORMANCE OF THIS SOFTWARE.
-
-#ifndef SIGNAL_SET_H
-#define SIGNAL_SET_H
-
-#include <exceptions/exceptions.h>
-#include <boost/function.hpp>
-#include <boost/noncopyable.hpp>
-#include <boost/shared_ptr.hpp>
-#include <set>
-#include <signal.h>
-
-namespace isc {
-namespace util {
-namespace io {
-
-/// @brief Exception thrown when the @c isc::util::io::SignalSet class
-/// experiences an error.
-class SignalSetError : public Exception {
-public:
-    SignalSetError(const char* file, size_t line, const char* what) :
-        isc::Exception(file, line, what) { };
-};
-
-/// @brief Forward declaration to the @c isc::util::io::SignalSet.
-class SignalSet;
-/// @brief Pointer to the @c isc::util::io::SignalSet.
-typedef boost::shared_ptr<SignalSet> SignalSetPtr;
-/// @brief Pointer to the signal handling function.
-typedef boost::function<void(int signum)> SignalHandler;
-
-/// @brief Represents a collection of signals handled in a customized way.
-///
-/// Kea processes must handle selected signals in a specialized way. For
-/// example: SIGINT and SIGTERM must perform a graceful shut down of the
-/// server. The SIGHUP signal is used to trigger server's reconfiguration.
-///
-/// This class allows specifying signals which should be handled in a
-/// specialized way as well as specifying a signal handler function.
-/// When a signal is received the signal handler function is called and
-/// the code of the received signal is recorded. This function doesn't
-/// do anything beyond recording the signal number to minimize the time
-/// spent on handling the signal and process interruption. The process
-/// can later check the signals received and call the handlers on its
-/// descretion by calling a @c isc::util::io::SignalSet::handleNext function.
-///
-/// @note This class is not thread safe. It uses static variables and
-/// functions to track a global state of signal registration and received
-/// signals' queue.
-class SignalSet : public boost::noncopyable {
-public:
-
-    /// @brief Constructor installing one signal.
-    ///
-    /// @param sig0 First signal.
-    /// @throw SignalSetError If attempting to add duplicated signal or
-    /// the signal is invalid.
-    SignalSet(const int sig0);
-
-    /// @brief Constructor installing two signals.
-    ///
-    /// @param sig0 First signal.
-    /// @param sig1 Second signal.
-    /// @throw SignalSetError If attempting to add duplicated signal or
-    /// the signal is invalid.
-    SignalSet(const int sig0, const int sig1);
-
-    /// @brief Constructor installing three signals.
-    ///
-    /// @param sig0 First signal.
-    /// @param sig1 Second signal.
-    /// @param sig2 Third signal.
-    /// @throw SignalSetError If attempting to add duplicated signal or
-    /// the signal is invalid.
-    SignalSet(const int sig0, const int sig1, const int sig2);
-
-    /// @brief Destructor.
-    ///
-    /// Removes installed handlers.
-    ~SignalSet();
-
-    /// @brief Installs the handler for the specified signal.
-    ///
-    /// This function adds a signal to the set. When the signal is received
-    /// by the process, it will be recorded and a signal can be later handled
-    /// by the process.
-    ///
-    /// @param sig Signal code.
-    /// @throw SignalSetError if signal being added duplicates an existing
-    /// signal.
-    void add(const int sig);
-
-    /// @brief Uninstalls all signals.
-    ///
-    /// This function calls @c isc::util::io::SignalSet::remove for each
-    /// installed signal.
-    void clear();
-
-    /// @brief Returns a code of the next received signal.
-    ///
-    /// @return A code of the next received signal or -1 if there are no
-    /// more signals received.
-    int getNext() const;
-
-    /// @brief Calls a handler for the next received signal.
-    ///
-    /// This function handles the next received signal and removes it from the
-    /// queue of received signals. While the function is executed, all custom
-    /// signal handlers are blocked to prevent race condition.
-    ///
-    /// @param signal_handler A pointer to the signal handler function to
-    /// be used to handle the signal.
-    void handleNext(SignalHandler signal_handler);
-
-    /// @brief Uninstalls signal handler for a specified signal.
-    ///
-    /// @param sig A code of the signal to be removed.
-    void remove(const int sig);
-
-private:
-
-    /// @brief Blocks signals in the set.
-    ///
-    /// This function blocks the signals in a set to prevent race condition
-    /// between the signal handler and the new signal coming in.
-    void block() const {
-        maskSignals(SIG_BLOCK);
-    }
-
-    /// @brief Removes the signal from the set.
-    ///
-    /// This function removes only a signal which is owned by this signal set.
-    ///
-    /// @param sig Signal to be removed.
-    /// @throw SignalSetError if the signal being removed is not owned by this
-    /// signal set.
-    void erase(const int sig);
-
-    /// @brief Insert a signal to the set.
-    ///
-    /// @param sig Signal to be inserted.
-    /// @throw SignalSetError if a signal being inserted has already been
-    /// registered in this or other signal set.
-    void insert(const int sig);
-
-    /// @brief Applies a mask to all signals in the set.
-    ///
-    /// This function is used by @c SignalSet::block and @c SignalSet::unblock
-    /// to apply the SIG_BLOCK and SIG_UNBLOCK mask to signals.
-    ///
-    /// @param mask A mask to be applied to all signals.
-    void maskSignals(const int mask) const;
-
-    /// @brief Pops a next signal number from the static collection of signals.
-    ///
-    /// The static collection of signals is updated by the internal signal
-    /// handler being invoked when one of the installed signals is received by
-    /// the process. This function removes the first element of the collection.
-    void popNext();
-
-    /// @brief Unblocks signals in the set.
-    ///
-    /// This function unblocks the signals in a set.
-    void unblock() const {
-        maskSignals(SIG_UNBLOCK);
-    }
-
-    /// @brief Stores the set of signals registered in this signal set.
-    std::set<int> local_signals_;
-};
-
-}
-}
-}
-
-#endif // SIGNAL_SET_H
-
diff --git a/src/lib/util/io/tests/Makefile.am b/src/lib/util/io/tests/Makefile.am
deleted file mode 100644
index d71c28b8c3..0000000000
--- a/src/lib/util/io/tests/Makefile.am
+++ /dev/null
@@ -1,31 +0,0 @@
-SUBDIRS = .
-
-AM_CPPFLAGS = -I$(top_builddir)/src/lib -I$(top_srcdir)/src/lib
-AM_CPPFLAGS += $(BOOST_INCLUDES)
-AM_CXXFLAGS = $(B10_CXXFLAGS)
-
-if USE_STATIC_LINK
-AM_LDFLAGS = -static
-endif
-
-CLEANFILES = *.gcno *.gcda
-
-TESTS_ENVIRONMENT = \
-        $(LIBTOOL) --mode=execute $(VALGRIND_COMMAND)
-
-TESTS =
-if HAVE_GTEST
-TESTS += run_unittests
-run_unittests_SOURCES  = run_unittests.cc
-run_unittests_SOURCES += signal_set_unittest.cc
-
-run_unittests_CPPFLAGS = $(AM_CPPFLAGS) $(GTEST_INCLUDES)
-run_unittests_LDFLAGS = $(AM_LDFLAGS) $(GTEST_LDFLAGS)
-
-run_unittests_LDADD  = $(top_builddir)/src/lib/exceptions/libkea-exceptions.la
-run_unittests_LDADD += $(top_builddir)/src/lib/util/io/libkea-util-io.la
-run_unittests_LDADD += $(GTEST_LDADD)
-
-endif
-
-noinst_PROGRAMS = $(TESTS)
diff --git a/src/lib/util/io/tests/run_unittests.cc b/src/lib/util/io/tests/run_unittests.cc
deleted file mode 100644
index 304c652382..0000000000
--- a/src/lib/util/io/tests/run_unittests.cc
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright (C) 2014  Internet Systems Consortium, Inc. ("ISC")
-//
-// Permission to use, copy, modify, and/or distribute this software for any
-// purpose with or without fee is hereby granted, provided that the above
-// copyright notice and this permission notice appear in all copies.
-//
-// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
-// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
-// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
-// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
-// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
-// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
-// PERFORMANCE OF THIS SOFTWARE.
-
-#include <log/logger_support.h>
-#include <gtest/gtest.h>
-
-int
-main(int argc, char* argv[]) {
-    ::testing::InitGoogleTest(&argc, argv);
-    int result = RUN_ALL_TESTS();
-    return (result);
-}
diff --git a/src/lib/util/io/tests/signal_set_unittest.cc b/src/lib/util/io/tests/signal_set_unittest.cc
deleted file mode 100644
index 9fcd4fda47..0000000000
--- a/src/lib/util/io/tests/signal_set_unittest.cc
+++ /dev/null
@@ -1,188 +0,0 @@
-// Copyright (C) 2014 Internet Systems Consortium, Inc. ("ISC")
-//
-// Permission to use, copy, modify, and/or distribute this software for any
-// purpose with or without fee is hereby granted, provided that the above
-// copyright notice and this permission notice appear in all copies.
-//
-// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
-// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
-// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
-// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
-// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
-// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
-// PERFORMANCE OF THIS SOFTWARE.
-
-#include <util/io/signal_set.h>
-#include <boost/bind.hpp>
-#include <boost/shared_ptr.hpp>
-#include <gtest/gtest.h>
-#include <signal.h>
-
-namespace {
-
-using namespace isc;
-using namespace isc::util::io;
-
-/// @brief Test fixture class for @c isc::util::io::SignalSet class.
-///
-/// This class contains a handler function which records the signal
-/// being handled. It allows for checking whether the signal set
-/// has invoked the handler for the expected signal.
-class SignalSetTest : public ::testing::Test {
-public:
-
-    /// @brief Constructor.
-    ///
-    /// Resets the signal sets and variables being modified by the
-    /// signal handler function.
-    SignalSetTest()
-        : signal_set_(),
-          secondary_signal_set_() {
-        handler_calls_ = 0;
-        signum_ = -1;
-    }
-
-    /// @brief Destructor.
-    ///
-    /// Uninstalls the signals from the signal sets.
-    ~SignalSetTest() {
-        if (signal_set_) {
-            signal_set_->clear();
-        }
-        if (secondary_signal_set_) {
-            secondary_signal_set_->clear();
-        }
-    }
-
-    /// @brief Signal handler used by unit tests.
-    ///
-    /// @param signum Signal being handled.
-    static void testHandler(int signum) {
-        signum_ = signum;
-        ++handler_calls_;
-    }
-
-    /// @brief Number of handler calls so far.
-    static int handler_calls_;
-    /// @brief The last signal handled.
-    static int signum_;
-    /// @brief Test signal set object.
-    SignalSetPtr signal_set_;
-    /// @brief Second signal set object.
-    SignalSetPtr secondary_signal_set_;
-};
-
-int SignalSetTest::handler_calls_ = 0;
-int SignalSetTest::signum_ = -1;
-
-/// Check that the signals are recorded by the signal handlers.
-TEST_F(SignalSetTest, twoSignals) {
-    // Register handlers for two signals.
-    signal_set_.reset(new SignalSet(SIGHUP, SIGINT));
-    // Send SIGHUP signal to the process.
-    ASSERT_EQ(0, raise(SIGHUP));
-    // The SIGHUP should be the next one in the queue to be handled.
-    EXPECT_EQ(SIGHUP, signal_set_->getNext());
-    // But, no handlers should have been called yet.
-    EXPECT_EQ(0, handler_calls_);
-    // Send a different signal.
-    ASSERT_EQ(0, raise(SIGINT));
-    // The SIGHUP hasn't been handled yet so it should still be the first
-    // one in the queue.
-    EXPECT_EQ(SIGHUP, signal_set_->getNext());
-    // No handlers have been called yet.
-    EXPECT_EQ(0, handler_calls_);
-    // Raise another SIGHUP before the first one has been handled. The
-    // second one should be dropped.
-    ASSERT_EQ(0, raise(SIGHUP));
-    // Execute the first handler (for SIGHUP).
-    signal_set_->handleNext(boost::bind(&SignalSetTest::testHandler, _1));
-    // The handler should have been called once and the signal
-    // handled should be SIGHUP.
-    EXPECT_EQ(1, handler_calls_);
-    EXPECT_EQ(SIGHUP, signum_);
-    // Next signal to be handled should be SIGINT.
-    EXPECT_EQ(SIGINT, signal_set_->getNext());
-    signal_set_->handleNext(boost::bind(&SignalSetTest::testHandler, _1));
-    EXPECT_EQ(2, handler_calls_);
-    EXPECT_EQ(SIGINT, signum_);
-    // There should be no more waiting handlers.
-    EXPECT_EQ(-1, signal_set_->getNext());
-    // Make sure that signals can be unregistered.
-    EXPECT_NO_THROW(signal_set_->remove(SIGHUP));
-    EXPECT_NO_THROW(signal_set_->remove(SIGINT));
-}
-
-/// Check that the signal set can only handle signals owned by it.
-TEST_F(SignalSetTest, twoSignalSets) {
-    // Register handler for SIGHUP in the first signal set.
-    signal_set_.reset(new SignalSet(SIGHUP));
-    // Register handler for SIGINT in the second signal set.
-    secondary_signal_set_.reset(new SignalSet(SIGINT));
-    // Send SIGHUP.
-    ASSERT_EQ(0, raise(SIGHUP));
-    // Send SIGINT.
-    ASSERT_EQ(0, raise(SIGINT));
-    // Although the SIGHUP is the first signal received by the process
-    // it is not owned by the secondary signal set. The first signal
-    // to be handled by the secondary signal set is SIGINT.
-    EXPECT_EQ(SIGINT, secondary_signal_set_->getNext());
-    // The signal set owns SIGHUP so it should be the next to handle.
-    EXPECT_EQ(SIGHUP, signal_set_->getNext());
-    // Handle next signal owned by the secondary signal set.
-    secondary_signal_set_->handleNext(boost::bind(&SignalSetTest::testHandler,
-                                                  _1));
-    EXPECT_EQ(1, handler_calls_);
-    EXPECT_EQ(SIGINT, signum_);
-    // No more signals to be handled for this signal set.
-    EXPECT_EQ(-1, secondary_signal_set_->getNext());
-    // Handle next signal owned by the signal set.
-    signal_set_->handleNext(boost::bind(&SignalSetTest::testHandler, _1));
-    EXPECT_EQ(2, handler_calls_);
-    EXPECT_EQ(SIGHUP, signum_);
-    // No more signals to be handled by this signal set.
-    EXPECT_EQ(-1, signal_set_->getNext());
-}
-
-// Check that each signal set removes only the signals that it has been used
-// to register.
-TEST_F(SignalSetTest, remove) {
-    // Register handlers for SIGHUP using one signal set.
-    ASSERT_NO_THROW(signal_set_.reset(new SignalSet(SIGHUP)));
-    // Define another signal set and register a different signal.
-    ASSERT_NO_THROW(secondary_signal_set_.reset(new SignalSet(SIGINT)));
-    // The SIGHUP has been already registsred with the other signal
-    // set, so it should not be possible to register it again.
-    ASSERT_THROW(secondary_signal_set_->add(SIGHUP), SignalSetError);
-    // It shouldn't be possible to remove the signal registered in a different
-    // signal set.
-    ASSERT_THROW(secondary_signal_set_->remove(SIGHUP), SignalSetError);
-    // Remove all signals from the first signal set. The signals registered
-    // with the other signal signal set should be preserved.
-    ASSERT_NO_THROW(signal_set_->clear());
-    // Check indirectly that the SIGINT is still registered. An attempt to
-    // register registered signal should result in failure.
-    EXPECT_THROW(secondary_signal_set_->add(SIGINT), SignalSetError);
-    // But, we should be able to regsiter SIGHUP.
-    EXPECT_NO_THROW(secondary_signal_set_->add(SIGHUP));
-}
-
-/// Check that it is not possible to duplicate signals.
-TEST_F(SignalSetTest, duplicates) {
-    ASSERT_NO_THROW(signal_set_.reset(new SignalSet(SIGHUP)));
-    // It shouldn't be possible to register the same signal.
-    EXPECT_THROW(signal_set_->add(SIGHUP), SignalSetError);
-    // But ok to register a different one.
-    EXPECT_NO_THROW(signal_set_->add(SIGTERM));
-    // Now, let's define other signal set.
-    SignalSetPtr other;
-    // SIGINT hasn't been registered in the first signal set
-    // so it should be fine to register.
-    ASSERT_NO_THROW(other.reset(new SignalSet(SIGINT)));
-    // SIGHUP has been already registered in the first signal set so
-    // an attempt to register it again should result in a failure.
-    EXPECT_THROW(other->add(SIGHUP), SignalSetError);
-}
-
-
-} // end of anonymous namespace