Some initial work towards making DECRQCRA less wrong

doc/changes.md

@@ -407,6 +407,8 @@ as part of K95 at this time, the default terminal remains VT220 for now.
    width if the parameters value is 0. Any value less than 80 will now produce an
    80 column terminal.
  - Fixed crash writing to unopened file
+ - Fixed DECFRA accepting invalid fill character specifications
+ - Fixed DECFRA not using the selected remote character set for the fill character
 
 ## Kermit 95 v3.0 beta 7 - 27 January 2025
 

doc/ctlseqs.xml

@@ -16252,10 +16252,17 @@ DCS $ q 3 , } ST</pre>
                 this will only be available to VT420 and higher emulations.
             </p>
             <p>
-                <param-single symbol="Pc"/> is the character
-                to fill with, while <tt><param-single symbol="Pt"/> ;
-                <param-single symbol="Pl"/> ; <param-single symbol="Pb"/> ;
-                <param-single symbol="Pr"/></tt> is the rectangle to fill
+                <tt><param-single symbol="Pt"/> ;
+                    <param-single symbol="Pl"/> ; <param-single symbol="Pb"/> ;
+                    <param-single symbol="Pr"/></tt> is the rectangle to fill.
+            </p>
+            <p>
+                <param-single symbol="Pc"/> is an integer referring to a
+                character in the current GL or GR character set to fill the
+                specified rectangular area. When not in UTF8 mode, it must fall
+                in the range 32-126 (GL) or 160-255 (GR). If the remote
+                character set is UTF8, then the second range is extended to
+                160-65535 to cover the Unicode base multilingual plane.
             </p>
         </section>
         <section role="ctlseq" id="decrqpkfm" mnemonic="DECRQPKFM"

kermit/k95/ckoco2.c

@@ -1865,7 +1865,7 @@ VscrnScrollLf( BYTE vmode, USHORT TopRow, USHORT LeftCol, USHORT BotRow,
             }
         for ( x = RightCol - Columns + 1 ; x <= RightCol ; x++ ){
             line->cells[x] = Cell ;
-            line->vt_char_attrs[x] = VT_CHAR_ATTR_NORMAL ;
+            line->vt_char_attrs[x] = VT_CHAR_ATTR_ERASED ;
             }
         }
 
@@ -1912,7 +1912,7 @@ VscrnScrollRt( BYTE vmode, USHORT TopRow, USHORT LeftCol, USHORT BotRow,
             }
         for ( x = LeftCol + Columns - 1 ; x >= LeftCol ; x-- ){
             line->cells[x] = Cell ;
-            line->vt_char_attrs[x] = VT_CHAR_ATTR_NORMAL ;
+            line->vt_char_attrs[x] = VT_CHAR_ATTR_ERASED ;
             }
         }
 
@@ -2045,6 +2045,7 @@ USHORT vtattrib_to_int(vtattrib vta) {
                 (vta.unerasable ? VT_CHAR_ATTR_PROTECTED : 0) |
                 (vta.graphic    ? VT_CHAR_ATTR_GRAPHIC   : 0) |
                 (vta.crossedout ? VT_CHAR_ATTR_CROSSEDOUT: 0) |
+                (vta.erased     ? VT_CHAR_ATTR_ERASED    : 0) |
                 (vta.hyperlink  ? VT_CHAR_ATTR_HYPERLINK : 0) |
                 (vta.wyseattr   ? WY_CHAR_ATTR         : 0) ;
 
@@ -2077,7 +2078,7 @@ VscrnWrtCell( BYTE vmode, viocell Cell, vtattrib att, USHORT Row, USHORT Col )
         for ( i=0 ; i<MAXTERMCOL  ; i++ ) {
             line->cells[i].c = ' ' ;
             line->cells[i].video_attr = cellcolor ;
-            line->vt_char_attrs[i] = VT_CHAR_ATTR_NORMAL ;
+            line->vt_char_attrs[i] = VT_CHAR_ATTR_ERASED ;
         }
     }
 
@@ -2642,6 +2643,7 @@ VscrnGetVtCharAttr( BYTE vmode, SHORT x, SHORT y )
     vta.graphic         = attr & VT_CHAR_ATTR_GRAPHIC ? 1 : 0 ;
     vta.wyseattr        = attr & WY_CHAR_ATTR ? 1 : 0 ;
     vta.crossedout      = attr & VT_CHAR_ATTR_CROSSEDOUT ? 1 : 0 ;
+    vta.erased          = attr & VT_CHAR_ATTR_ERASED ? 1 : 0 ;
     vta.hyperlink       = attr & VT_CHAR_ATTR_HYPERLINK ? 1 : 0;
     vta.linkid          = attr & VT_CHAR_ATTR_HYPERLINK ? line->hyperlinks[x] : 0;
 
@@ -3646,7 +3648,7 @@ VscrnScrollPage(BYTE vmode, int updown, int topmargin, int bottommargin,
                     line->vt_line_attr = VT_LINE_ATTR_NORMAL ;
                     for ( x = 0 ; x < MAXTERMCOL ; x++ ) {
                         line->cells[x] = blankcell ;
-                        line->vt_char_attrs[x] = VT_CHAR_ATTR_NORMAL ;
+                        line->vt_char_attrs[x] = VT_CHAR_ATTR_ERASED ;
                     }
                 }
 
@@ -3685,7 +3687,7 @@ VscrnScrollPage(BYTE vmode, int updown, int topmargin, int bottommargin,
                     for ( x = 0 ; x < MAXTERMCOL ; x++ )
                         {
                         line->cells[x] = blankcell ;
-                        line->vt_char_attrs[x] = VT_CHAR_ATTR_NORMAL ;
+                        line->vt_char_attrs[x] = VT_CHAR_ATTR_ERASED ;
                         }
                     }
                 }
@@ -3730,7 +3732,7 @@ VscrnScrollPage(BYTE vmode, int updown, int topmargin, int bottommargin,
                 line->vt_line_attr = VT_LINE_ATTR_NORMAL ;
                 for ( x = 0 ; x < MAXTERMCOL ; x++ ) {
                     line->cells[x] = blankcell ;
-                    line->vt_char_attrs[x] = VT_CHAR_ATTR_NORMAL ;
+                    line->vt_char_attrs[x] = VT_CHAR_ATTR_ERASED ;
                 }
             }
             break;
@@ -5675,7 +5677,7 @@ VscrnInit( BYTE vmode )
                         	for ( x = 0 ; x < MAXTERMCOL ; x++ ) {
                             	line->cells[x].c = ' ' ;
                             	line->cells[x].video_attr = vmode == VTERM ? attribute : colorcmd;
-                            	line->vt_char_attrs[x] = VT_CHAR_ATTR_NORMAL ;
+                            	line->vt_char_attrs[x] = VT_CHAR_ATTR_ERASED ;
                         	}
                     	}
                 	}
@@ -5730,6 +5732,10 @@ VscrnIsClear( BYTE vmode, int page )
                 debug(F100,"VscrnIsClear video_attr != cellcolor","",0);
                 return 0;
             }
+			/* TODO: Ideally we'd check if VT_CHAR_ATTR_ERASED is set too, but
+             *       in order to do that we'd need to be *certain* that all
+             *       emulations are correctly setting and clearing the attribute
+             *       which is not currently the case. */
         }
     }
     debug(F100,"VscrnIsClear all clear","",0);