1 files changed, 35 insertions, 7 deletions

diff --git a/src/syncevo/SuspendFlags.h b/src/syncevo/SuspendFlags.h
index a45c1154..e6f9c07f 100644
--- a/src/syncevo/SuspendFlags.h
+++ b/src/syncevo/SuspendFlags.h
@@ -56,7 +56,9 @@ class SuspendFlags
         /** suspend sync request received again (only written to event FD, not returned by getState()) */
         SUSPEND_AGAIN,
         /** abort sync request received again (only written to event FD, not returned by getState()) */
-        ABORT_AGAIN
+        ABORT_AGAIN,
+
+        ABORT_MAX
     };
 
     /** access to singleton */
@@ -73,6 +75,12 @@ class SuspendFlags
     State getState() const;
 
     /**
+     * Returns or-ed mask of all signals handled so far.
+     * See activate().
+     */
+    uint32_t getReceivedSignals() const { return m_receivedSignals; }
+
+    /**
      * Throws a "aborting as requested by user" StatusException with
      * LOCERR_USERABORT as status code if the current state is not
      * NORMAL. In other words, suspend and abort are both
@@ -83,7 +91,7 @@ class SuspendFlags
     /**
      * Users of this class can read a single char for each received
      * signal from this file descriptor. The char is the State that
-     * was entered by that signal. This can be used to be notified
+      * was entered by that signal. This can be used to be notified
      * immediately about changes, without having to poll.
      *
      * -1 if not activated.
@@ -96,11 +104,25 @@ class SuspendFlags
     };
 
     /**
-     * Allocate file descriptors, set signal handlers for SIGINT and
-     * SIGTERM. Once the returned guard is freed, it will
-     * automatically deactivate signal handling.
+     * Allocate file descriptors, set signal handlers for the chosen
+     * signals (SIGINT and SIGTERM by default). Once the returned
+     * guard is freed, it will automatically deactivate signal
+     * handling.
+     *
+     * Additional signals like SIGURG or SIGIO may also be used. It is
+     * unlikely that any library used by SyncEvolution occupies these
+     * signals for its own use.
+     *
+     * Only SIGINT and SIGTERM influence the overall State. All
+     * received signals, including SIGINT and SIGTERM, are recorded
+     * and can be retrieved via getReceivedSignals().
+     *
+     * It is possible to call activate multiple times. All following
+     * calls do nothing except creating a new reference to the same
+     * guard.  In particular they cannot add or remove handled
+     * signals.
      */
-    boost::shared_ptr<Guard> activate();
+    boost::shared_ptr<Guard> activate(uint32_t sigmask = (1<<SIGINT)|(1<<SIGTERM));
 
     /**
      * Retrieve state changes pushed into pipe by signal
@@ -162,12 +184,18 @@ class SuspendFlags
     /** state as observed by signal handler */
     State m_state;
 
+    /** or-ed bit mask of all received signals */
+    uint32_t m_receivedSignals;
+
     /** time is measured inside signal handler */
     time_t m_lastSuspend;
 
     int m_senderFD, m_receiverFD;
-    struct sigaction m_oldSigInt, m_oldSigTerm;
+    // For the sake of simplicity we only support signals in the 1-31 range.
+    uint32_t m_activeSignals;
+    struct sigaction m_oldSignalHandlers[32];
 
+    boost::weak_ptr<Guard> m_guard;
     boost::weak_ptr<StateBlocker> m_suspendBlocker, m_abortBlocker;
     boost::shared_ptr<StateBlocker> block(boost::weak_ptr<StateBlocker> &blocker);
 };