- This implements a solution that lets any GUI take over handling of any

signal.  First, selection of the GUI should cause BX_GUI_SIGHANDLER to
  be defined in config.h.in.  Then, the GUI should define member functions
    Bit32u get_sighandler_mask ();
    void sighandler (int sig);
  The mask function returns a bitfield where one bit corresponds to each
  signal.  For any signal whose bit is set to 1 in the return value of
  get_sighandler_mask, the gui will control that signal.  When the signal
  arrives, bx_gui.sighandler(sig) will be called by bx_signal_handler,
  instead of the default behavior of that signal.

bochs/bochs.h

@@ -260,6 +260,7 @@ typedef struct {
   void* record_io;
   } bx_debug_t;
 
+void bx_signal_handler (int signum);
 void bx_printf(char *fmt, ...);
 void bx_panic(char *fmt, ...);
 void bx_atexit(void);

bochs/config.h.in

@@ -404,6 +404,9 @@ typedef unsigned int Boolean;
 #endif
 #endif // BX_WITH_WIN32
 
+// for now only term.cc requires a GUI sighandler.
+#define BX_GUI_SIGHANDLER (BX_WITH_TERM)
+
 #define HAVE_SIGACTION 1
 
 // configure will change the definition of "inline" to the value

bochs/debug/dbg_main.cc

@@ -353,6 +353,7 @@ process_sim2:
 
   // (mch) Moved from main.cc
   bx_devices.init();
+  bx_gui.init_signal_handlers ();
   bx_pc_system.start_timers();
 
   // setup Ctrl-C handler

bochs/gui/gui.cc

@@ -21,7 +21,7 @@
 //  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 
 
-
+#include <signal.h>
 #include "bochs.h"
 #include "gui/bitmaps/floppya.h"
 #include "gui/bitmaps/floppyb.h"
@@ -190,3 +190,16 @@ bx_gui_c::gui_set_mouse_enable(Boolean val)
 {
   bx_options.mouse_enabled = val;
 }
+
+void 
+bx_gui_c::init_signal_handlers ()
+{
+#if BX_GUI_SIGHANDLER
+  Bit32u mask = get_sighandler_mask ();
+  for (Bit32u sig=0; sig<32; sig++)
+  {
+    if (mask & (1<<sig))
+      signal (sig, bx_signal_handler);
+  }
+#endif
+}

bochs/gui/gui.h

@@ -51,6 +51,14 @@ public:
   static Boolean  gui_get_mouse_enable(void);
   static void     gui_set_mouse_enable(Boolean val);
   static void     exit(void);
+  static void init_signal_handlers ();
+#if BX_GUI_SIGHANDLER
+  // returns 32-bit bitmask in which 1 means the GUI should handle that signal
+  static Bit32u get_sighandler_mask ();
+  // called when registered signal arrives
+  static void sighandler (int sig);
+#endif
+
 
 private:
   // And these are defined and used privately in gui.cc

bochs/gui/term.cc

@@ -79,8 +79,20 @@ do_scan(int key_event, int shift, int ctrl, int alt)
 //     always assumes the width of the current VGA mode width, but
 //     it's height is defined by this parameter.
 
-static void
-guisig(int signo)
+Bit32u 
+bx_gui_c::get_sighandler_mask ()
+{
+  return 
+    (1<<SIGHUP)
+    | (1<<SIGINT)
+    | (1<<SIGQUIT)
+    | (1<<SIGSTOP)
+    | (1<<SIGTSTP)
+    | (1<<SIGTERM);
+}
+
+void
+bx_gui_c::sighandler(int signo)
 {
 	switch(signo) {
 	case SIGINT:
@@ -124,14 +136,6 @@ bx_gui_c::specific_init(bx_gui_c *th, int argc, char **argv, unsigned tilewidth,
 	nodelay(stdscr, TRUE);
 	noecho();
 
-	bx_printf ("bx_gui_c::specific_init is defining signal handlers now");
-	(void)signal(SIGHUP, guisig);
-	(void)signal(SIGINT, guisig);
-	(void)signal(SIGQUIT, guisig);
-	(void)signal(SIGSTOP, guisig);
-	(void)signal(SIGTSTP, guisig);
-	(void)signal(SIGTERM, guisig);
-
 	if (bx_options.private_colormap)
 		if(bx_dbg.video)
 			bx_printf("#TERM] WARNING: private_colormap option ignored.\n");

bochs/main.cc

@@ -22,14 +22,6 @@
 
 
 
-
-
-
-
-void bx_signal_handler(int signum);
-
-
-
 #include "bochs.h"
 #include "state_file.h"
 
@@ -188,7 +180,7 @@ bx_bochs_init(int argc, char *argv[])
 
 #if BX_DEBUGGER == 0
   bx_devices.init();
-
+  bx_gui.init_signal_handlers ();
   bx_pc_system.start_timers();
 #endif
 
@@ -928,5 +920,12 @@ bx_signal_handler( int signum)
     }
 #endif
 
+#if BX_GUI_SIGHANDLER
+  if ((1<<signum) & bx_gui.get_sighandler_mask ()) {
+    bx_gui.sighandler (signum);
+    return;
+  }
+#endif
+
   bx_panic("SIGNAL %u caught\n", signum);
 }