have core ask windowport if suspend is ok

PORTS: Please make sure I've done the right thing for/to your code.
This patch adds a new winproc that lets the window port approve or cancel
the suspend request - this should take care of the Mac Qt lockup issue.
In addition, Unix suspend is restricted to accounts that can use the shell
if SYSCF is defined.

doc/window.doc

@@ -488,6 +488,9 @@ suspend_nhwindows(str)
 		-- Prepare the window to be suspended.
 resume_nhwindows()
 		-- Restore the windows after being suspended.
+can_suspend()   -- Tell the core if the window system will allow the game
+                   to be suspended now.  If unconditionally yes or no, use
+		   genl_can_suspend_yes() or genl_can_suspend_no().
 
 start_screen()	-- Only used on Unix tty ports, but must be declared for
 		   completeness.  Sets up the tty to work in full-screen

include/extern.h

@@ -2574,6 +2574,8 @@ E boolean FDECL(mwelded, (struct obj *));
 /* ### windows.c ### */
 
 E void FDECL(choose_windows, (const char *));
+E boolean NDECL(genl_can_suspend_no);
+E boolean NDECL(genl_can_suspend_yes);
 E char FDECL(genl_message_menu, (CHAR_P,int,const char *));
 E void FDECL(genl_preference_update, (const char *));
 E char *FDECL(genl_getmsghistory, (BOOLEAN_P));

include/winprocs.h

@@ -80,6 +80,7 @@ struct window_procs {
     void FDECL((*win_status_threshold), (int,int,anything,int,int,int));
 # endif
 #endif
+    boolean NDECL((*win_can_suspend));
 };
 
 extern

src/cmd.c

@@ -109,6 +109,8 @@ extern int NDECL(dozap); /**/
 extern int NDECL(doorganize); /**/
 #endif /* DUMB */
 
+static int NDECL(dosuspend_core); /**/
+
 static int NDECL((*timed_occ_fn));
 
 STATIC_PTR int NDECL(doprev_message);
@@ -2124,9 +2126,7 @@ static const struct func_tab cmdlist[] = {
 	{C('w'), TRUE, wiz_wish},
 #endif
 	{C('x'), TRUE, doattributes},
-#ifdef SUSPEND
-	{C('z'), TRUE, dosuspend},
-#endif
+	{C('z'), TRUE, dosuspend_core},
 	{'a', FALSE, doapply},
 	{'A', FALSE, doddoremarm},
 	{M('a'), TRUE, doorganize},
@@ -3586,4 +3586,16 @@ char def;
 	return (*windowprocs.win_yn_function)(qbuf, resp, def);
 }
 
+int
+dosuspend_core(){
+#ifdef SUSPEND
+		/* Does current window system support suspend? */
+	if( (*windowprocs.win_can_suspend)()){
+			/* NB: SYSCF SHELLERS handled in port code. */
+		dosuspend();
+	} else
+#endif
+		Norep("Suspend command not available.");
+}
+
 /*cmd.c*/

src/windows.c

@@ -88,6 +88,16 @@ struct win_choices {
     { 0, 0 }		/* must be last */
 };
 
+boolean
+genl_can_suspend_no(){
+    return FALSE;
+}
+
+boolean
+genl_can_suspend_yes(){
+    return TRUE;
+}
+
 STATIC_OVL
 void
 def_raw_print(s)
@@ -316,6 +326,7 @@ static struct window_procs hup_procs = {
     genl_status_threshold,
 #  endif
 # endif /* STATUS_VIA_WINDOWPORT */
+    genl_can_suspend_no,
 };
 
 static void FDECL((*previnterface_exit_nhwindows), (const char *)) = 0;

sys/amiga/winami.c

@@ -93,6 +93,7 @@ struct window_procs amii_procs =
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_yes,
 };
 
 /* The view window layout uses the same function names so we can use
@@ -164,6 +165,7 @@ struct window_procs amiv_procs =
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_yes,
 };
 
 unsigned short amii_initmap[ AMII_MAXCOLORS ];

sys/mac/macwin.c

@@ -3293,6 +3293,7 @@ struct window_procs mac_procs = {
 	0, //    mac_end_screen,
 	genl_outrip,
 	genl_preference_update,
+	genl_can_suspend_no,
 };
 
 /*macwin.c*/

sys/share/ioctl.c

@@ -155,6 +155,16 @@ setioctls()
 int
 dosuspend()
 {
+#ifdef SYSCF
+		/* NB: check_user_string() is port-specific. */
+	if(   !sysopt.shellers
+	   || !sysopt.shellers[0]
+	   || !check_user_string(sysopt.shellers)
+	){
+		Norep("Suspend command not available.");
+		return;
+	}
+#endif
 # ifdef SIGTSTP
 	if(signal(SIGTSTP, SIG_IGN) == SIG_DFL) {
 		suspend_nhwindows((char *)0);

sys/unix/sysconf

@@ -9,11 +9,11 @@
 # A value of * allows anyone to enter debugging mode.
 WIZARDS=root,games
 
-# Users allowed to use the ! (shell escape) command.  Uses the same syntax
-# as the WIZARDS option above.
+# Users allowed to use the ! (shell escape) command or to suspend the game.
+# Uses the same syntax as the WIZARDS option above.
 #SHELLERS=
 
-# Limit the number of simultaneous games (see also and nethack.sh).
+# Limit the number of simultaneous games (see also nethack.sh).
 MAXPLAYERS=10
 
 # If not null, added to string "To get local support, " in the support

sys/wince/mswproc.c

@@ -108,6 +108,7 @@ struct window_procs mswin_procs = {
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_no,
 };
 
 /*  

win/X11/winX.c

@@ -173,6 +173,7 @@ struct window_procs X11_procs = {
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_no,	/* XXX may not always be correct */
 };
 
 /*

win/gem/wingem.c

@@ -111,6 +111,7 @@ struct window_procs Gem_procs = {
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_no,
 };
 
 #ifdef MAC

win/gnome/gnbind.c

@@ -90,6 +90,7 @@ struct window_procs Gnome_procs = {
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_yes,
 };
 
 /*  

win/tty/wintty.c

@@ -137,6 +137,7 @@ struct window_procs tty_procs = {
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_yes,
 };
 
 static int maxwin = 0;			/* number of windows in use */

win/win32/mswproc.c

@@ -136,6 +136,7 @@ struct window_procs mswin_procs = {
     genl_status_threshold,
 # endif
 #endif
+    genl_can_suspend_yes,
 };