custom cursor style

Signed-off-by: Neil Johnson <najohnsn@us.ibm.com>

tnz/_termlib.py

@@ -435,6 +435,8 @@ def refresh(self, *, _win_callback=None):
             if curs_vis:
                 if curs_vis == 2:
                     pendlist.append("\x1b[1 q")
+                elif curs_vis < 0:
+                    pendlist.append(f"\x1b[{-curs_vis-1} q")
                 else:
                     pendlist.append("\x1b[3 q")
 
@@ -1032,6 +1034,10 @@ def color_pair(cls, pair_number):
     @_log_errors
     def curs_set(cls, visibility):
         """Set cursor visibility.
+           0  - Invisible
+           1  - Terminal-specific normal mode
+           2  - Terminal-specific high visibility mode
+           <0 - Use absolute value minus one for DECSCUSR value
         """
         cls.__initscr_required()
 
@@ -1040,6 +1046,8 @@ def curs_set(cls, visibility):
         if cls.__alt_screen:
             if visibility == 2:
                 cls.__termo.write("\x1b[1 q\x1b[?25h")
+            elif visibility < 0:
+                cls.__termo.write(f"\x1b[{-visibility-1} q\x1b[?25h")
             elif visibility:
                 cls.__termo.write("\x1b[3 q\x1b[?25h")
             else:

tnz/zti.py

@@ -27,6 +27,8 @@
     TNZ_LOGGING (see tnz.py)
     ZTI_AIDBUFSIZE (9 is default)
     ZTI_AUTOSIZE
+    ZTI_CURSOR_INSERT
+    ZTI_CURSOR_REPLACE
     ZTI_SECLEVEL (see tnz.py)
     ZTI_TITLE
     _BPX_TERMPATH (see _termlib.py)
@@ -35,6 +37,7 @@
 
 SPDX-License-Identifier: Apache-2.0
 """
+
 if __name__ == "__main__":
     # We want to support starting by 'python -m tnz.zti', but that can
     # generally be problematic because the zti module is imported as
@@ -47,6 +50,7 @@
     # eventually dropping support for 'python -m tnz.zti' so that we can
     # avoid this.
     from tnz import zti
+
     raise SystemExit(zti.main())
 
 import atexit
@@ -135,7 +139,7 @@ def __init__(self, stdin=None, stdout=None):
         self.__has_color = None
 
         self.__prog_curs_vis = 0  # cursor invisible in prog mode
-        self.__cur_curs_vis = 1  # current cursor state
+        self.__cur_curs_vis = -1  # current cursor state
         self.__shell_mousemask = None
 
         self.ddmrecv = False  # allow host-initiated ind$file get
@@ -1483,6 +1487,17 @@ def __color_setup(self):
 
             self.__has_color = False
 
+    def __curs_vis(self, insmode):
+        if insmode:
+            curval = os.getenv("ZTI_CURSOR_INSERT", "")
+        else:
+            curval = os.getenv("ZTI_CURSOR_REPLACE", "")
+
+        if curval.isdigit():
+            return -int(curval)-1
+
+        return 2 if insmode else 1
+
     def __dirty_range(self, start, end, tns=None):
         """Mark a range of screen addresses as dirty.
 
@@ -1978,7 +1993,7 @@ def __r2d2(self, win, waitc, timeout):
         if show:
             self.__prog_curs_vis = 0
         else:
-            self.__prog_curs_vis = 1
+            self.__prog_curs_vis = self.__curs_vis(False)
 
         tout = timeout
         if timeout > 0:
@@ -2038,10 +2053,8 @@ def __r2d2(self, win, waitc, timeout):
                                 currow <= endy and
                                 curcol > begx and
                                 curcol <= endx):
-                            if insmode:
-                                self.__prog_curs_vis = 2  # very visible
-                            else:
-                                self.__prog_curs_vis = 1  # visible
+                            curs_vis = self.__curs_vis(insmode)
+                            self.__prog_curs_vis = curs_vis
 
                             xpos, ypos = self.twin_loc
                             _logger.debug("before win.move")
@@ -2330,10 +2343,7 @@ def __r2d2(self, win, waitc, timeout):
                     _logger.debug("keyed Insert")
 
                     insmode = (not insmode)
-                    if insmode:
-                        self.__prog_curs_vis = 2  # very visible
-                    else:
-                        self.__prog_curs_vis = 1  # visible
+                    self.__prog_curs_vis = self.__curs_vis(insmode)
 
                 elif (cstr == "\x1b1" or  # ESC+1 (Alt+1)
                       cstr == "ALT_1" or  # ESC+1 (Alt+1)