2002-06-18 Marcus Brinkmann <marcus@gnu.org>

	* console.h: Update all CONS_KEY_* macros to match other terminfo
	definitions (like "linux", "screen", "gnome").  Add CONS_CHAR_*
	macros for terminal graphic characters.

	* display.c (struct attr): New member ALTCHAR to flag usage of
	alternate character set.
	(display_notice_filechange): Make static.
	(handle_escape_bracket_m): Set ALTCHAR to 0 when resetting.
	Support new modes 10 and 11 to disable and enable ALTCHAR.
	(limit_cursor): New function, moved to global scope from ...
	(handle_escape_bracket): ... here.
	(linefeed): New function, moved to global scope from ...
	(display_output_one): ... here.
	(horizontal_tab): New function.
	(handle_escape_bracket): Add alias \E[' to \E[G for VT100
	compatibility.  Add capability \E[a (horizontal cursor position
	relative) for ECMA-48 compatibility.  Add capabilities \E[I
	(horizontal tab) and \E[Z (backward tabulation) for ECMA-48
	compatibility.  Move capabilities \E[s and \E[u to ...
	(display_output_one): ... here as \E7 and \E8 for VT100
	compatibility.
	(altchar_to_ucs4): New function.
	(display_output_one): Use altchar_to_ucs4 when in altchar mode.
	Add \EM (reset) capability.

3 files changed, 362 insertions, 97 deletions

diff --git a/console/ChangeLog b/console/ChangeLog
index 62b292ad..9e86d139 100644
--- a/console/ChangeLog
+++ b/console/ChangeLog
@@ -1,3 +1,30 @@
+2002-06-18  Marcus Brinkmann  <marcus@gnu.org>
+
+	* console.h: Update all CONS_KEY_* macros to match other terminfo
+	definitions (like "linux", "screen", "gnome").  Add CONS_CHAR_*
+	macros for terminal graphic characters.
+
+	* display.c (struct attr): New member ALTCHAR to flag usage of
+	alternate character set.
+	(display_notice_filechange): Make static.
+	(handle_escape_bracket_m): Set ALTCHAR to 0 when resetting.
+	Support new modes 10 and 11 to disable and enable ALTCHAR.
+	(limit_cursor): New function, moved to global scope from ...
+	(handle_escape_bracket): ... here.
+	(linefeed): New function, moved to global scope from ...
+	(display_output_one): ... here.
+	(horizontal_tab): New function.
+	(handle_escape_bracket): Add alias \E[' to \E[G for VT100
+	compatibility.  Add capability \E[a (horizontal cursor position
+	relative) for ECMA-48 compatibility.  Add capabilities \E[I
+	(horizontal tab) and \E[Z (backward tabulation) for ECMA-48
+	compatibility.  Move capabilities \E[s and \E[u to ...
+	(display_output_one): ... here as \E7 and \E8 for VT100
+	compatibility.
+	(altchar_to_ucs4): New function.
+	(display_output_one): Use altchar_to_ucs4 when in altchar mode.
+	Add \EM (reset) capability.
+
 2002-06-17  Marcus Brinkmann  <marcus@gnu.org>
 
 	* console.c (new_node): Adjust size of display node.
diff --git a/console/console.h b/console/console.h
index 771351f5..d1f06492 100644
--- a/console/console.h
+++ b/console/console.h
@@ -94,27 +94,114 @@ struct cons_display
 };
 
 
-#define CONS_KEY_UP		"\e[A"		/* Cursor up.  */
-#define CONS_KEY_DOWN		"\e[B"		/* Cursor down.  */
-#define CONS_KEY_RIGHT		"\e[C"		/* Cursor right.  */
-#define CONS_KEY_LEFT		"\e[D"		/* Cursor left.  */
-#define CONS_KEY_HOME		"\e[H"		/* Home key.  */
+/* The console server will use the following UCS-4 characters for the
+   specified terminal graphic characters.  If the display driver is
+   UCS-4 capabable, it can print them without interpretation.  */
+
+/* ACS_BLOCK maps to FULL BLOCK.  */
+#define CONS_CHAR_BLOCK		((wchar_t) 0x2588)
+/* ACS_DIAMOND maps to BLACK DIAMOND.  */
+#define CONS_CHAR_DIAMOND	((wchar_t) 0x25c6)
+/* ACS_CKBOARD maps to MEDIUM SHADE.  */
+#define CONS_CHAR_CKBOARD	((wchar_t) 0x2592)
+/* ACS_BOARD maps to LIGHT SHADE.  */
+#define CONS_CHAR_BOARD		((wchar_t) 0x2591)
+/* ACS_BULLET maps to BULLET (Linux maps it to MIDDLE DOT 0x00b7).  */
+#define CONS_CHAR_BULLET	((wchar_t) 0x2022)
+/* ACS_STERLING maps to POUND STERLING.  */
+#define CONS_CHAR_STERLING	((wchar_t) 0x00a3)
+/* ACS_DEGREE maps to DEGREE SIGN.  */
+#define CONS_CHAR_DEGREE	((wchar_t) 0x00b0)
+/* ACS_PLMINUS maps to PLUS-MINUS SIGN.  */
+#define CONS_CHAR_PLMINUS	((wchar_t) 0x00b1)
+/* ACS_PI maps to GREEK SMALL LETTER PI.  */
+#define CONS_CHAR_PI		((wchar_t) 0x03c0)
+/* ACS_LANTERN maps to BLACK HOURGLASS.  XXX Is this appropriate?  */
+#define CONS_CHAR_LANTERN	((wchar_t) 0x29d7)
+
+/* ACS_RARROW maps to RIGHTWARDS ARROW.  */
+#define CONS_CHAR_RARROW	((wchar_t) 0x2192)
+/* ACS_LARROW maps to LEFTWARDS ARROW.  */
+#define CONS_CHAR_LARROW	((wchar_t) 0x2190)
+/* ACS_UARROW maps to UPWARDS ARROW.  */
+#define CONS_CHAR_UARROW	((wchar_t) 0x2191)
+/* ACS_DARROW maps to DOWNWARDS ARROW.  */
+#define CONS_CHAR_DARROW	((wchar_t) 0x2193)
+
+/* ACS_LRCORNER maps to BOX DRAWINGS LIGHT UP AND LEFT.  */
+#define CONS_CHAR_LRCORNER	((wchar_t) 0x2518)
+/* ACS_URCORNER maps to BOX DRAWINGS LIGHT DOWN AND LEFT.  */
+#define CONS_CHAR_URCORNER	((wchar_t) 0x2510)
+/* ACS_ULCORNER maps to BOX DRAWINGS LIGHT DOWN AND RIGHT.  */
+#define CONS_CHAR_ULCORNER	((wchar_t) 0x250c)
+/* ACS_LLCORNER maps to BOX DRAWINGS LIGHT UP AND RIGHT.  */
+#define CONS_CHAR_LLCORNER	((wchar_t) 0x2514)
+/* ACS_PLUS maps to BOX DRAWINGS LIGHT VERTICAL AND HORIZONTAL.  */
+#define CONS_CHAR_PLUS		((wchar_t) 0x253c)
+/* ACS_HLINE maps to BOX DRAWINGS LIGHT HORIZONTAL.  */
+#define CONS_CHAR_HLINE		((wchar_t) 0x2500)
+/* ACS_LTEE maps to BOX DRAWINGS LIGHT VERTICAL AND RIGHT.  */
+#define CONS_CHAR_LTEE		((wchar_t) 0x251c)
+/* ACS_RTEE maps to BOX DRAWINGS LIGHT VERTICAL AND LEFT.  */
+#define CONS_CHAR_RTEE		((wchar_t) 0x2524)
+/* ACS_BTEE maps to BOX DRAWINGS LIGHT UP AND HORIZONTAL.  */
+#define CONS_CHAR_BTEE		((wchar_t) 0x2534)
+/* ACS_TTEE maps to BOX DRAWINGS LIGHT DOWN AND HORIZONTAL.  */
+#define CONS_CHAR_TTEE		((wchar_t) 0x252c)
+/* ACS_VLINE maps to BOX DRAWINGS LIGHT VERTICAL.  */
+#define CONS_CHAR_VLINE		((wchar_t) 0x2502)
+
+/* ACS_S1 maps to HORIZONTAL SCAN LINE-1.  */
+#define CONS_CHAR_S1		((wchar_t) 0x23ba)
+/* ACS_S3 maps to HORIZONTAL SCAN LINE-3.  */
+#define CONS_CHAR_S3		((wchar_t) 0x23bb)
+/* ACS_S7 maps to HORIZONTAL SCAN LINE-1.  */
+#define CONS_CHAR_S7		((wchar_t) 0x23bc)
+/* ACS_S9 maps to HORIZONTAL SCAN LINE-1.  */
+#define CONS_CHAR_S9		((wchar_t) 0x23bd)
+
+/* ACS_NEQUAL maps to NOT EQUAL TO.  */
+#define CONS_CHAR_NEQUAL	((wchar_t) 0x2260)
+/* ACS_LEQUAL maps to LESS-THAN OR EQUAL TO.  */
+#define CONS_CHAR_LEQUAL	((wchar_t) 0x2264)
+/* ACS_GEQUAL maps to GREATER-THAN OR EQUAL TO.  */
+#define CONS_CHAR_GEQUAL	((wchar_t) 0x2265)
+
+
+
+/* The input driver should emit these escape sequences for special
+   keys which don't represent characters in UTF-8.  */
+#define CONS_KEY_UP		"\eOA"		/* Cursor up.  */
+#define CONS_KEY_DOWN		"\eOB"		/* Cursor down.  */
+#define CONS_KEY_RIGHT		"\eOC"		/* Cursor right.  */
+#define CONS_KEY_LEFT		"\eOD"		/* Cursor left.  */
 #define CONS_KEY_BACKSPACE	"\177"		/* Backspace key.  */
 #define CONS_KEY_F1		"\eOP"		/* Function key 1.  */
 #define CONS_KEY_F2		"\eOQ"		/* Function key 2.  */
 #define CONS_KEY_F3		"\eOR"		/* Function key 3.  */
 #define CONS_KEY_F4		"\eOS"		/* Function key 4.  */
-#define CONS_KEY_F5		"\eOT"		/* Function key 5.  */
-#define CONS_KEY_F6		"\eOU"		/* Function key 6.  */
-#define CONS_KEY_F7		"\eOV"		/* Function key 7.  */
-#define CONS_KEY_F8		"\eOW"		/* Function key 8.  */
-#define CONS_KEY_F9		"\eOX"		/* Function key 9.  */
-#define CONS_KEY_F10		"\eOY"		/* Function key 10.  */
-#define CONS_KEY_DC		"\e[9"		/* Delete character.  */
-#define CONS_KEY_NPAGE		"\e[U"		/* Next page.  */
-#define CONS_KEY_PPAGE		"\e[V"		/* Previous page.  */
+#define CONS_KEY_F5		"\e[15~"	/* Function key 5.  */
+#define CONS_KEY_F6		"\e[17~"	/* Function key 6.  */
+#define CONS_KEY_F7		"\e[18~"	/* Function key 7.  */
+#define CONS_KEY_F8		"\e[19~"	/* Function key 8.  */
+#define CONS_KEY_F9		"\e[20~"	/* Function key 9.  */
+#define CONS_KEY_F10		"\e[21~"	/* Function key 10.  */
+#define CONS_KEY_F11		"\e[23~"	/* Function key 11.  */
+#define CONS_KEY_F12		"\e[24~"	/* Function key 12.  */
+#define CONS_KEY_F13		"\e[25~"	/* Function key 13.  */
+#define CONS_KEY_F14		"\e[26~"	/* Function key 14.  */
+#define CONS_KEY_F15		"\e[28~"	/* Function key 15.  */
+#define CONS_KEY_F16		"\e[29~"	/* Function key 16.  */
+#define CONS_KEY_F17		"\e[31~"	/* Function key 17.  */
+#define CONS_KEY_F18		"\e[32~"	/* Function key 18.  */
+#define CONS_KEY_F19		"\e[33~"	/* Function key 19.  */
+#define CONS_KEY_F20		"\e[34~"	/* Function key 20.  */
+#define CONS_KEY_HOME		"\e[1~"		/* Home key.  */
+#define CONS_KEY_IC		"\e[2~"		/* Insert char mode.  */
+#define CONS_KEY_DC		"\e[3~"		/* Delete character.  */
+#define CONS_KEY_END		"\e[4~"		/* End key.  */
+#define CONS_KEY_PPAGE		"\e[5~"		/* Previous page.  */
+#define CONS_KEY_NPAGE		"\e[6~"		/* Next page.  */
 #define CONS_KEY_BTAB		"\e[Z"		/* Back tab key.  */
-#define CONS_KEY_IC		"\e[@"		/* Insert char mode.  */
-#define CONS_KEY_END		"\e[Y"		/* End key.  */
 
 #endif	/* _HURD_CONSOLE_H */
diff --git a/console/display.c b/console/display.c
index 45190c1e..5528ff98 100644
--- a/console/display.c
+++ b/console/display.c
@@ -123,6 +123,8 @@ struct attr
   unsigned int bgcol_def;
   unsigned int fgcol_def;
   conchar_attr_t current;
+  /* True if in alternate character set (ASCII graphic) mode.  */
+  unsigned int altchar;
 };
 typedef struct attr *attr_t;
 
@@ -296,7 +298,7 @@ display_notice_changes (display_t display, mach_port_t notify)
 }
 
 /* Requires DISPLAY to be locked.  */
-void
+static void
 display_notice_filechange (display_t display, enum file_changed_type type,
 			   off_t start, off_t end)
 {
@@ -391,7 +393,6 @@ display_flush_filechange (display_t display, unsigned int type)
     }
 }
 
-
 /* Record a change in the matrix ringbuffer.  */
 static void
 display_record_filechange (display_t display, off_t start, off_t end)
@@ -470,7 +471,6 @@ display_record_filechange (display_t display, off_t start, off_t end)
       display->changes.end = end;
     }
 }
-      
 	    
 
 static void
@@ -737,6 +737,7 @@ handle_esc_bracket_m (attr_t attr, int code)
       memset (&attr->current, 0, sizeof (conchar_attr_t));
       attr->current.fgcol = attr->fgcol_def;
       attr->current.bgcol = attr->bgcol_def;
+      attr->altchar = 0;
       break;
     case 1:
       /* Bold on: <bold>.  */
@@ -762,6 +763,14 @@ handle_esc_bracket_m (attr_t attr, int code)
       /* Concealed on: <invis>.  */
       attr->current.concealed = 1;
       break;
+    case 10:
+      /* Alternate character set mode off: <rmacs>.  */
+      attr->altchar = 0;
+      break;
+    case 11:
+      /* Alternate character set mode on: <smacs>.  */
+      attr->altchar = 1;
+      break;
     case 22:
       /* Normal intensity.  */
       attr->current.intensity = CONS_ATTR_INTENSITY_NORMAL;
@@ -801,27 +810,71 @@ handle_esc_bracket_m (attr_t attr, int code)
     }
 }
 
+static
+void limit_cursor (display_t display)
+{
+  struct cons_display *user = display->user;
+
+  if (user->cursor.col >= user->screen.width)
+    user->cursor.col = user->screen.width - 1;
+  else if (user->cursor.col < 0)
+    user->cursor.col = 0;
+      
+  if (user->cursor.row >= user->screen.height)
+    user->cursor.row = user->screen.height - 1;
+  else if (user->cursor.row < 0)
+    user->cursor.row = 0;
+  
+  /* XXX Flag cursor change.  */
+}
+
+
 static void
-handle_esc_bracket (display_t display, char op)
+linefeed (display_t display)
 {
   struct cons_display *user = display->user;
-  parse_t parse = &display->output.parse;
-  int i;
 
-  static void limit_cursor (void)
+  if (user->cursor.row < user->screen.height - 1)
     {
-      if (user->cursor.col >= user->screen.width)
-	user->cursor.col = user->screen.width - 1;
-      else if (user->cursor.col < 0)
-	user->cursor.col = 0;
-      
-      if (user->cursor.row >= user->screen.height)
-	user->cursor.row = user->screen.height - 1;
-      else if (user->cursor.row < 0)
-	user->cursor.row = 0;
+      user->cursor.row++;
+      /* XXX Flag cursor update.  */
+    }
+  else
+    {
+      user->screen.cur_line++;
+      user->screen.cur_line %= user->screen.lines;
 
-      /* XXX Flag cursor change.  */
+      screen_fill (display, 0, user->screen.height - 1,
+		   user->screen.width - 1, user->screen.height - 1,
+		   L' ', display->attr.current);
+      if (user->screen.scr_lines <
+	  user->screen.lines - user->screen.height)
+	user->screen.scr_lines++;
+      /* XXX Flag current line change.  */
+      /* XXX Possibly flag change of length of scroll back buffer.  */
+    }
+}
+
+static void
+horizontal_tab (display_t display)
+{
+  struct cons_display *user = display->user;
+
+  user->cursor.col = (user->cursor.col | 7) + 1;
+  if (user->cursor.col >= user->screen.width)
+    {
+      user->cursor.col = 0;
+      linefeed (display);
     }
+  /* XXX Flag cursor update.  */
+}
+
+static void
+handle_esc_bracket (display_t display, char op)
+{
+  struct cons_display *user = display->user;
+  parse_t parse = &display->output.parse;
+  int i;
 
   switch (op)
     {
@@ -830,18 +883,24 @@ handle_esc_bracket (display_t display, char op)
       /* Cursor position: <cup>.  */
       user->cursor.col = (parse->params[1] ?: 1) - 1;
       user->cursor.row = (parse->params[0] ?: 1) - 1;
-      limit_cursor ();
+      limit_cursor (display);
       break;
     case 'G':		/* ECMA-48 <CHA>.  */
     case '`':		/* ECMA-48 <HPA>.  */
+    case '\'':		/* VT100.  */
       /* Horizontal cursor position: <hpa>.  */
       user->cursor.col = (parse->params[0] ?: 1) - 1;
-      limit_cursor ();
+      limit_cursor (display);
+      break;
+    case 'a':		/* ECMA-48 <HPR>.  */
+      /* Horizontal cursor position relative.  */
+      user->cursor.col += (parse->params[1] ?: 1) - 1;
+      limit_cursor (display);
       break;
     case 'd':		/* ECMA-48 <VPA>.  */
-      /* Vertical cursor position: <hpa>.  */
+      /* Vertical cursor position: <vpa>.  */
       user->cursor.row = (parse->params[0] ?: 1) - 1;
-      limit_cursor ();
+      limit_cursor (display);
       break;
     case 'F':		/* ECMA-48 <CPL>.  */
       /* Beginning of previous line.  */
@@ -851,7 +910,7 @@ handle_esc_bracket (display_t display, char op)
     case 'k':		/* ECMA-48 <VPB>.  */
       /* Cursor up: <cuu>, <cuu1>.  */
       user->cursor.row -= (parse->params[0] ?: 1);
-      limit_cursor ();
+      limit_cursor (display);
       break;
     case 'E':		/* ECMA-48 <CNL>.  */
       /* Beginning of next line.  */
@@ -861,29 +920,17 @@ handle_esc_bracket (display_t display, char op)
     case 'e':		/* ECMA-48 <VPR>.  */
       /* Cursor down: <cud1>, <cud>.  */
       user->cursor.row += (parse->params[0] ?: 1);
-      limit_cursor ();
+      limit_cursor (display);
       break;
     case 'C':		/* ECMA-48 <CUF>.  */
       /* Cursor right: <cuf1>, <cuf>.  */
       user->cursor.col += (parse->params[0] ?: 1);
-      limit_cursor ();
+      limit_cursor (display);
       break;
     case 'D':		/* ECMA-48 <CUB>.  */
       /* Cursor left: <cub>, <cub1>.  */
       user->cursor.col -= (parse->params[0] ?: 1);
-      limit_cursor ();
-      break;
-    case 's':
-      /* Save cursor position: <sc>.  */
-      display->cursor.saved_x = user->cursor.col;
-      display->cursor.saved_y = user->cursor.row;
-      break;
-    case 'u':
-      /* Restore cursor position: <rc>.  */
-      user->cursor.col = display->cursor.saved_x;
-      user->cursor.row = display->cursor.saved_y;
-      /* In case the screen was larger before:  */
-      limit_cursor ();
+      limit_cursor (display);
       break;
     case 'h':
       /* Reset mode.  */
@@ -895,11 +942,11 @@ handle_esc_bracket (display_t display, char op)
       for (i = 0; i < parse->nparams; i++)
 	handle_esc_bracket_hl (display, parse->params[i], 1);
       break;
-    case 'm':		/* ECME-48 <SGR>.  */
+    case 'm':		/* ECMA-48 <SGR>.  */
       for (i = 0; i < parse->nparams; i++)
 	handle_esc_bracket_m (&display->attr, parse->params[i]);
       break;
-    case 'J':		/* ECME-48 <ED>.  */
+    case 'J':		/* ECMA-48 <ED>.  */
       switch (parse->params[0])
 	{
 	case 0:
@@ -922,7 +969,7 @@ handle_esc_bracket (display_t display, char op)
 	  break;
 	}
       break;
-    case 'K':		/* ECME-48 <EL>.  */
+    case 'K':		/* ECMA-48 <EL>.  */
       switch (parse->params[0])
 	{
 	case 0:
@@ -945,55 +992,90 @@ handle_esc_bracket (display_t display, char op)
 	  break;
 	}
       break;
-    case 'L':		/* ECME-48 <IL>.  */
+    case 'L':		/* ECMA-48 <IL>.  */
       /* Insert line(s): <il1>, <il>.  */
       screen_shift_right (display, 0, user->cursor.row,
 			  user->screen.width - 1, user->screen.height - 1,
 			  (parse->params[0] ?: 1) * user->screen.width,
 			  L' ', display->attr.current);
       break;
-    case 'M':		/* ECME-48 <DL>.  */
+    case 'M':		/* ECMA-48 <DL>.  */
       /* Delete line(s): <dl1>, <dl>.  */
       screen_shift_left (display, 0, user->cursor.row,
 			 user->screen.width - 1, user->screen.height - 1,
 			 (parse->params[0] ?: 1) * user->screen.width,
 			 L' ', display->attr.current);
       break;
-    case '@':		/* ECME-48 <ICH>.  */
+    case '@':		/* ECMA-48 <ICH>.  */
       /* Insert character(s): <ich1>, <ich>.  */
       screen_shift_right (display, user->cursor.col, user->cursor.row,
 			  user->screen.width - 1, user->cursor.row,
 			  parse->params[0] ?: 1,
 			  L' ', display->attr.current);
       break;
-    case 'P':		/* ECME-48 <DCH>.  */
+    case 'P':		/* ECMA-48 <DCH>.  */
       /* Delete character(s): <dch1>, <dch>.  */
       screen_shift_left (display, user->cursor.col, user->cursor.row,
 			 user->screen.width - 1, user->cursor.row,
 			 parse->params[0] ?: 1,
 			 L' ', display->attr.current);
       break;
-    case 'S':		/* ECME-48 <SU>.  */
+    case 'S':		/* ECMA-48 <SU>.  */
       /* Scroll up: <ind>, <indn>.  */
       screen_shift_left (display, 0, 0,
 			 user->screen.width - 1, user->screen.height - 1,
 			 (parse->params[0] ?: 1) * user->screen.width,
 			 L' ', display->attr.current);
       break;
-    case 'T':		/* ECME-48 <SD>.  */
+    case 'T':		/* ECMA-48 <SD>.  */
       /* Scroll down: <ri>, <rin>.  */
       screen_shift_right (display, 0, 0,
 			  user->screen.width, user->screen.height,
 			  (parse->params[0] ?: 1) * user->screen.width,
 			  L' ', display->attr.current);
       break;
-    case 'X':		/* ECME-48 <ECH>.  */
+    case 'X':		/* ECMA-48 <ECH>.  */
       /* Erase character(s): <ech>.  */
       screen_fill (display, user->cursor.col, user->cursor.row,
 		   /* XXX limit ? */user->cursor.col + (parse->params[0] ?: 1),
 		   user->cursor.row,
 		   L' ', display->attr.current);
       break;
+    case 'I':		/* ECMA-48 <CHT>.  */
+      /* Horizontal tab.  */
+      if (!parse->params[0])
+	parse->params[0] = 1;
+      while (parse->params[0]--)
+	horizontal_tab (display);
+      break;
+    case 'Z':		/* ECMA-48 <CBT>.  */
+      /* Cursor backward tabulation: <cbt>.  */
+      if (parse->params[0] > user->screen.height * (user->screen.width / 8))
+	{
+	  user->cursor.col = 0;
+	  user->cursor.row = 0;
+	}
+      else
+	{
+	  int i = parse->params[0] ?: 1;
+
+	  while (i--)
+	    {
+	      if (user->cursor.col == 0)
+		{
+		  if (user->cursor.row == 0)
+		    break;
+		  else
+		    {
+		      user->cursor.col = user->screen.width - 1;
+		      user->cursor.row--;
+		    }
+		}
+	      else
+		user->cursor.col--;
+	      user->cursor.col &= ~7;
+	    }
+	}
     }
 }
 
@@ -1035,6 +1117,81 @@ handle_esc_bracket_question (display_t display, char op)
     }
 }
 
+static wchar_t
+altchar_to_ucs4 (wchar_t chr)
+{
+  /* Alternative character set frobbing.  */
+  switch (chr)
+    {
+    case L'+':
+      return CONS_CHAR_RARROW;
+    case L',':
+      return CONS_CHAR_LARROW;
+    case L'-':
+      return CONS_CHAR_UARROW;
+    case L'.':
+      return CONS_CHAR_DARROW;
+    case L'0':
+      return CONS_CHAR_BLOCK;
+    case L'I':
+      return CONS_CHAR_LANTERN;
+    case L'`':
+      return CONS_CHAR_DIAMOND;
+    case L'a':
+      return CONS_CHAR_CKBOARD;
+    case L'f':
+      return CONS_CHAR_DEGREE;
+    case L'g':
+      return CONS_CHAR_PLMINUS;
+    case L'h':
+      return CONS_CHAR_BOARD;
+    case L'j':
+      return CONS_CHAR_LRCORNER;
+    case L'k':
+      return CONS_CHAR_URCORNER;
+    case L'l':
+      return CONS_CHAR_ULCORNER;
+    case L'm':
+      return CONS_CHAR_LLCORNER;
+    case L'n':
+      return CONS_CHAR_PLUS;
+    case L'o':
+      return CONS_CHAR_S1;
+    case L'p':
+      return CONS_CHAR_S3;
+    case L'q':
+      return CONS_CHAR_HLINE;
+    case L'r':
+      return CONS_CHAR_S7;
+    case L's':
+      return CONS_CHAR_S9;
+    case L't':
+      return CONS_CHAR_LTEE;
+    case L'u':
+      return CONS_CHAR_RTEE;
+    case L'v':
+      return CONS_CHAR_BTEE;
+    case L'w':
+      return CONS_CHAR_TTEE;
+    case L'x':
+      return CONS_CHAR_VLINE;
+    case L'y':
+      return CONS_CHAR_LEQUAL;
+    case L'z':
+      return CONS_CHAR_GEQUAL;
+    case L'{':
+      return CONS_CHAR_PI;
+    case L'|':
+      return CONS_CHAR_NEQUAL;
+    case L'}':
+      return CONS_CHAR_STERLING;
+    case L'~':
+      return CONS_CHAR_BULLET;
+    default:
+      return chr;
+    }
+}
+
 /* Display must be locked.  */
 static void
 display_output_one (display_t display, wchar_t chr)
@@ -1042,29 +1199,6 @@ display_output_one (display_t display, wchar_t chr)
   struct cons_display *user = display->user;
   parse_t parse = &display->output.parse;
 
-  void linefeed (void)
-    {
-      if (user->cursor.row < user->screen.height - 1)
-	{
-	  user->cursor.row++;
-	  /* XXX Flag cursor update.  */
-	}
-      else
-	{
-	  user->screen.cur_line++;
-	  user->screen.cur_line %= user->screen.lines;
-
-	  screen_fill (display, 0, user->screen.height - 1,
-		       user->screen.width - 1, user->screen.height - 1,
-		       L' ', display->attr.current);
-	  if (user->screen.scr_lines <
-	      user->screen.lines - user->screen.height)
-	    user->screen.scr_lines++;
-	  /* XXX Flag current line change.  */
-	  /* XXX Possibly flag change of length of scroll back buffer.  */
-	}
-    }
-
   switch (parse->state)
     {
     case STATE_NORMAL:
@@ -1080,7 +1214,7 @@ display_output_one (display_t display, wchar_t chr)
 	  break;
 	case L'\n':
 	  /* Line feed.  */
-	  linefeed ();
+	  linefeed (display);
 	  break;
 	case L'\b':
 	  /* Backspace.  */
@@ -1100,13 +1234,7 @@ display_output_one (display_t display, wchar_t chr)
 	  break;
 	case L'\t':
 	  /* Horizontal tab: <ht> */
-	  user->cursor.col = (user->cursor.col | 7) + 1;
-	  if (user->cursor.col >= user->screen.width)
-	    {
-	      user->cursor.col = 0;
-	      linefeed ();
-	    }
-	  /* XXX Flag cursor update.  */
+	  horizontal_tab (display);
 	  break;
 	case L'\033':
 	  parse->state = STATE_ESC;
@@ -1119,7 +1247,9 @@ display_output_one (display_t display, wchar_t chr)
 	    int line = (user->screen.cur_line + user->cursor.row)
 	      % user->screen.lines;
 	    int idx = line * user->screen.width + user->cursor.col;
-	    user->_matrix[idx].chr = chr;
+
+	    user->_matrix[idx].chr = display->attr.altchar
+	      ? altchar_to_ucs4 (chr) : chr;
 	    user->_matrix[idx].attr = display->attr.current;
 
 	    display_record_filechange (display, idx, idx);
@@ -1127,7 +1257,7 @@ display_output_one (display_t display, wchar_t chr)
 	    if (user->cursor.col == user->screen.width)
 	      {
 		user->cursor.col = 0;
-		linefeed ();
+		linefeed (display);
 	      }
 	  }
 	  break;
@@ -1140,6 +1270,13 @@ display_output_one (display_t display, wchar_t chr)
 	case L'[':
 	  parse->state = STATE_ESC_BRACKET_INIT;
 	  break;
+	case L'M':		/* ECMA-48 <RIS>.  */
+	  /* Reset: <rs2>.  */
+	  * (uint32_t *) &display->attr.current = 0;
+	  display->attr.current.bgcol = display->attr.bgcol_def;
+	  display->attr.current.fgcol = display->attr.fgcol_def;
+	  display->attr.altchar = 0;
+	  /* Fall through.  */
 	case L'c':
 	  /* Clear screen and home cursor: <clear>.  */
 	  screen_fill (display, 0, 0,
@@ -1152,7 +1289,19 @@ display_output_one (display_t display, wchar_t chr)
 	case L'E':		/* ECMA-48 <NEL>.  */
 	  /* Newline.  */
 	  user->cursor.col = 0;
-	  linefeed ();
+	  linefeed (display);
+	  break;
+	case L'7':		/* VT100: Save cursor and attributes.  */
+	  /* Save cursor position: <sc>.  */
+	  display->cursor.saved_x = user->cursor.col;
+	  display->cursor.saved_y = user->cursor.row;
+	  break;
+	case L'8':		/* VT100: Restore cursor and attributes.  */
+	  /* Restore cursor position: <rc>.  */
+	  user->cursor.col = display->cursor.saved_x;
+	  user->cursor.row = display->cursor.saved_y;
+	  /* In case the screen was larger before:  */
+	  limit_cursor (display);
 	  break;
 	default:
 	  /* Unsupported escape sequence.  */
@@ -1244,6 +1393,7 @@ display_output_some (display_t display, char **buffer, size_t *length)
   display_flush_filechange (display, ~0);
   return err;
 }
+
 
 void
 display_init (void)
@@ -1258,6 +1408,7 @@ display_init (void)
                                 (any_t)pager_bucket));
 }
 
+
 /* Create a new virtual console display, with the system encoding
    being ENCODING.  */
 error_t