New base/Signal.h: Exception safe signal handler save/restore.

diff --git a/zypp/CMakeLists.txt b/zypp/CMakeLists.txt
index 78c25eb..0b8519a 100644 (file)
--- a/zypp/CMakeLists.txt
+++ b/zypp/CMakeLists.txt
@@ -245,6 +245,7 @@ SET( zypp_base_HEADERS
   base/PtrTypes.h
   base/ReferenceCounted.h
   base/SafeBool.h
+  base/Signal.h
   base/String.h
   base/Regex.h
   base/Sysconfig.h

diff --git a/zypp/base/Signal.h b/zypp/base/Signal.h
new file mode 100644 (file)
index 0000000..e4ffd6a
--- /dev/null
+++ b/zypp/base/Signal.h
@@ -0,0 +1,84 @@
+/*---------------------------------------------------------------------\
+|                          ____ _   __ __ ___                          |
+|                         |__  / \ / / . \ . \                         |
+|                           / / \ V /|  _/  _/                         |
+|                          / /__ | | | | | |                           |
+|                         /_____||_| |_| |_|                           |
+|                                                                      |
+\---------------------------------------------------------------------*/
+/** \file      zypp/base/Signal.h
+ *
+*/
+#ifndef ZYPP_BASE_SIGNAL_H
+#define ZYPP_BASE_SIGNAL_H
+
+#include <csignal>
+#include <iosfwd>
+
+///////////////////////////////////////////////////////////////////
+namespace zypp
+{ /////////////////////////////////////////////////////////////////
+
+  /** Exception safe signal handler save/restore.
+   * \ingroup g_RAII
+   */
+  class SignalSaver
+  {
+    public:
+      SignalSaver( int signum_r, sighandler_t handler_r )
+      : _signum( signum_r )
+      { _orighandler = ::signal( signum_r, handler_r ); }
+      ~SignalSaver()
+      { ::signal( _signum, _orighandler ); }
+    private:
+      int _signum;
+      ::sighandler_t _orighandler;
+  };
+
+  /** Exception safe sigprocmask save/restore.
+   * \ingroup g_RAII
+   */
+  class SigprocmaskSaver
+  {
+    public:
+      /** Ctor saving the original sigprocmask. */
+      SigprocmaskSaver()
+      { ::sigprocmask( SIG_SETMASK, NULL, &_origmask ); }
+      /** Dtor restoring the original sigprocmask. */
+      ~SigprocmaskSaver()
+      { ::sigprocmask( SIG_SETMASK, &_origmask, NULL ); }
+    public:
+      /** Temporary block signal. */
+      void block( int signum_r )
+      {
+       ::sigset_t mask;
+       ::sigemptyset( & mask );
+       ::sigaddset( & mask, signum_r );
+       ::sigprocmask( SIG_BLOCK, &mask, NULL );
+      }
+      /** Temporary unblock signal. */
+      void unblock( int signum_r )
+      {
+       ::sigset_t mask;
+       ::sigemptyset( & mask );
+       ::sigaddset( & mask, signum_r );
+       ::sigprocmask( SIG_UNBLOCK, &mask, NULL );
+      }
+      /** Whether signal delivery is pending. */
+      bool pending( int signum_r )
+      {
+       ::sigset_t mask;
+       ::sigpending( &mask );
+       return ::sigismember( &mask, signum_r );
+      }
+      /** Wait for signals not blocked in original sigprocmask. */
+      void suspend()
+      { ::sigsuspend( &_origmask ); }
+    private:
+      ::sigset_t _origmask;
+  };
+
+  /////////////////////////////////////////////////////////////////
+} // namespace zypp
+///////////////////////////////////////////////////////////////////
+#endif // ZYPP_BASE_SIGNAL_H