tty: hide cursor unless waiting for user input

Use vi (cursor_invisible) and ve (cursor_normal) to hide and show
cursor, if the terminal supports those.  This way on a slower
connection the cursor doesn't jump all over the place when doing
map or menu updates.

doc/fixes3-7-0.txt

@@ -2210,6 +2210,7 @@ tty: add support for petattr
 tty: if a ^C interrupt occurred while DECgraphics characters were being drawn
 	on the map, the "Really quit?" prompt would be illegible due to being
 	rendered with VT line drawing characters
+tty: hide cursor unless waiting for user input
 Unix: when user name is used as default character name, keep hyphenated value
 	intact instead stripping off dash and whatever follows as if that
 	specified role/race/&c (worked once upon a time; broken since 3.3.0)

include/wintty.h

@@ -255,6 +255,7 @@ extern void tty_raw_print_bold(const char *);
 extern int tty_nhgetch(void);
 extern int tty_nh_poskey(coordxy *, coordxy *, int *);
 extern void tty_nhbell(void);
+extern void tty_curs_set(int);
 extern int tty_doprev_message(void);
 extern char tty_yn_function(const char *, const char *, char);
 extern void tty_getlin(const char *, char *);

win/tty/getline.c

@@ -79,7 +79,9 @@ hooked_tty_getlin(
     for (;;) {
         (void) fflush(stdout);
         Strcat(strcat(strcpy(gt.toplines, query), " "), obufp);
+        tty_curs_set(1);
         c = pgetchar();
+        tty_curs_set(0);
         if (c == '\033' || c == EOF) {
             if (c == '\033' && obufp[0] != '\0') {
                 obufp[0] = '\0';

win/tty/termcap.c

@@ -36,6 +36,10 @@ static void kill_hilite(void);
 /* (see tcap.h) -- nh_CM, nh_ND, nh_CD, nh_HI,nh_HE, nh_US,nh_UE, ul_hack */
 struct tc_lcl_data tc_lcl_data = { 0, 0, 0, 0, 0, 0, 0, FALSE };
 
+static char *nh_VI = (char *) 0; /* cursor_invisible */
+static char *nh_VE = (char *) 0; /* cursor_normal */
+/*static char *nh_VS = (char *) 0;*/ /* cursor_visible (highlighted cursor) */
+
 static char *HO, *CL, *CE, *UP, *XD, *BC, *SO, *SE, *TI, *TE;
 static char *VS, *VE;
 static char *ME, *MR, *MB, *MH, *MD;
@@ -280,6 +284,12 @@ tty_startup(int *wid, int *hgt)
     if (!ME)
         ME = SE ? SE : nullstr; /* default to SE value */
 
+    nh_VI = Tgetstr(nhStr("vi"));
+    nh_VE = Tgetstr(nhStr("ve"));
+    /*nh_VS = Tgetstr(nhStr("vs"));*/
+    if (!nh_VI || !nh_VE /*|| !nh_VS*/ )
+        nh_VI = nh_VE = /*nh_VS =*/ (char *) 0;
+
     /* Get rid of padding numbers for nh_HI and nh_HE.  Hope they
      * aren't really needed!!!  nh_HI and nh_HE are outputted to the
      * pager as a string - so how can you send it NULs???
@@ -737,6 +747,16 @@ tty_nhbell(void)
     (void) fflush(stdout);
 }
 
+/* hide or show cursor */
+void
+tty_curs_set(int visibility)
+{
+    if (!visibility && nh_VI)
+        xputs(nh_VI);
+    else if (visibility && nh_VE)
+        xputs(nh_VE);
+}
+
 #ifdef ASCIIGRAPH
 void
 graph_on(void)

win/tty/wintty.c

@@ -542,6 +542,7 @@ tty_init_nhwindows(int *argcp UNUSED, char **argv UNUSED)
     /* to port dependant tty setup */
     tty_startup(&wid, &hgt);
     setftty(); /* calls start_screen */
+    tty_curs_set(0);
 
     /* set up tty descriptor */
     ttyDisplay = (struct DisplayDesc *) alloc(sizeof (struct DisplayDesc));
@@ -807,6 +808,7 @@ tty_exit_nhwindows(const char *str)
 {
     winid i;
 
+    tty_curs_set(1);
     tty_suspend_nhwindows(str);
     /*
      * Disable windows to avoid calls to window routines.
@@ -3985,6 +3987,7 @@ tty_nhgetch(void)
 
     HUPSKIP_RESULT('\033');
     print_vt_code1(AVTC_INLINE_SYNC);
+    tty_curs_set(1);
     (void) fflush(stdout);
     /* Note: if raw_print() and wait_synch() get called to report terminal
      * initialization problems, then wins[] and ttyDisplay might not be
@@ -4018,6 +4021,7 @@ tty_nhgetch(void)
         }
 #endif
     }
+    tty_curs_set(0);
     if (!i)
         i = '\033'; /* map NUL to ESC since nethack doesn't expect NUL */
     else if (i == EOF)