--- rxvt-unicode/src/screen.C	2006/01/06 18:33:30	1.213
+++ rxvt-unicode/src/screen.C	2006/01/20 10:35:25	1.245
@@ -117,7 +117,7 @@
 
 /* Fill part/all of a line with blanks. */
 void
-rxvt_term::scr_blank_line (line_t &l, unsigned int col, unsigned int width, rend_t efs)
+rxvt_term::scr_blank_line (line_t &l, unsigned int col, unsigned int width, rend_t efs) const NOTHROW
 {
   if (!l.t)
     {
@@ -144,9 +144,12 @@
 /* ------------------------------------------------------------------------- */
 /* Fill a full line with blanks - make sure it is allocated first */
 void
-rxvt_term::scr_blank_screen_mem (line_t &l, rend_t efs)
+rxvt_term::scr_blank_screen_mem (line_t &l, rend_t efs) const NOTHROW
 {
   scr_blank_line (l, 0, ncol, efs);
+
+  l.l = 0;
+  l.f = 0;
 }
 
 /* ------------------------------------------------------------------------- *
@@ -178,7 +181,7 @@
       //TODO//FIXME
       saveLines++;
       prev_nrow--;
-      nsaved++;
+      top_row--;
     }
 
   want_refresh = 1;
@@ -193,18 +196,16 @@
     {
       /*
        * first time called so just malloc everything: don't rely on realloc
-       * Note: this is still needed so that all the scrollback lines are NULL
        */
-      nsaved = 0;       /* no saved lines */
+      top_row = 0;       /* no saved lines */
       term_start = 0;
 
       talloc = new rxvt_salloc (ncol * sizeof (text_t));
       ralloc = new rxvt_salloc (ncol * sizeof (rend_t));
 
-      row_buf   = (line_t *)rxvt_calloc (total_rows, sizeof (line_t));
-      temp_buf  = (line_t *)rxvt_calloc (total_rows, sizeof (line_t));
-      drawn_buf = (line_t *)rxvt_calloc (nrow      , sizeof (line_t));
-      swap_buf  = (line_t *)rxvt_calloc (nrow      , sizeof (line_t));
+      row_buf   = (line_t *)rxvt_calloc (total_rows + nrow, sizeof (line_t));
+      drawn_buf = (line_t *)rxvt_calloc (nrow             , sizeof (line_t));
+      swap_buf  = (line_t *)rxvt_calloc (nrow             , sizeof (line_t));
 
       for (int row = nrow; row--; )
         {
@@ -235,7 +236,6 @@
       selection.op = SELECTION_CLEAR;
       selection.screen = PRIMARY;
       selection.clicks = 0;
-      CLEAR_ALL_SELECTION ();
       rvideo = 0;
     }
   else
@@ -259,7 +259,6 @@
 #endif
 
       drawn_buf = (line_t *)rxvt_realloc (drawn_buf, nrow * sizeof (line_t));
-      temp_buf  = (line_t *)rxvt_realloc (temp_buf , nrow * sizeof (line_t));
       swap_buf  = (line_t *)rxvt_realloc (swap_buf , nrow * sizeof (line_t));
 
       for (int row = min (nrow, prev_nrow); row--; )
@@ -274,13 +273,14 @@
           drawn_buf[row].clear (); scr_blank_screen_mem (drawn_buf[row], DEFAULT_RSTYLE);
         }
 
-      line_t *old_buf = row_buf; row_buf = (line_t *)rxvt_calloc (total_rows, sizeof (line_t));
+      line_t *old_buf = row_buf;
+      row_buf = (line_t *)rxvt_calloc (total_rows + nrow, sizeof (line_t));
         
       int p    = MOD (term_start + prev_nrow, prev_total_rows);  // previous row
-      int pend = MOD (term_start - nsaved   , prev_total_rows);
+      int pend = MOD (term_start + top_row  , prev_total_rows);
       int q    = total_rows; // rewrapped row
 
-      if (nsaved)
+      if (top_row)
         {
           // re-wrap lines, this is rather ugly, possibly because I am too dumb
           // to come up with a lean and mean algorithm.
@@ -326,6 +326,10 @@
 
                   int qcol = 0;
 
+                  // see below for cursor adjustment rationale
+                  if (p == ocur.row)
+                    screen.cur.row = q - (total_rows - nrow);
+                  
                   // fill a single destination line
                   while (lofs < llen && qcol < ncol)
                     {
@@ -345,8 +349,10 @@
 
                       int len = min (min (prev_ncol - pcol, ncol - qcol), llen - lofs);
 
+#if DEBUG_STRICT
                       assert (len);
                       assert (pline.t);
+#endif
 
                       memcpy (qline->t + qcol, pline.t + pcol, len * sizeof (text_t));
                       memcpy (qline->r + qcol, pline.r + pcol, len * sizeof (rend_t));
@@ -363,11 +369,11 @@
           while (p != pend && q > 0);
 
           term_start = total_rows - nrow;
-          nsaved = term_start - q;
+          top_row = q - term_start;
  
           // make sure all terminal lines exist
-          while (nsaved < 0)
-            scr_blank_screen_mem (ROW (-++nsaved), DEFAULT_RSTYLE);
+          while (top_row > 0)
+            scr_blank_screen_mem (ROW (--top_row), DEFAULT_RSTYLE);
         }
       else
         {
@@ -390,11 +396,6 @@
           term_start = 0;
         }
 
-#ifdef DEBUG_STRICT //TODO: remove
-      for (int i = -nsaved; i < nrow; i++)
-        assert (ROW (i).t);
-#endif
-
       free (old_buf);
       delete old_ta;
       delete old_ra;
@@ -406,6 +407,8 @@
         free (tabs);
     }
 
+  CLEAR_ALL_SELECTION ();
+
   prev_nrow = nrow;
   prev_ncol = ncol;
 
@@ -424,7 +427,7 @@
  * Free everything.  That way malloc debugging can find leakage.
  */
 void
-rxvt_term::scr_release ()
+rxvt_term::scr_release () NOTHROW
 {
   delete talloc; talloc = 0;
   delete ralloc; ralloc = 0;
@@ -432,7 +435,6 @@
   free (row_buf);
   free (swap_buf);
   free (drawn_buf);
-  free (temp_buf);
   free (tabs);
 
   row_buf = 0; // signal that we freed all the arrays
@@ -443,14 +445,14 @@
  * Hard reset
  */
 void
-rxvt_term::scr_poweron ()
+rxvt_term::scr_poweron () NOTHROW
 {
   scr_release ();
   prev_nrow = prev_ncol = 0;
   scr_reset ();
 
   scr_clear (true);
-  scr_refresh (SLOW_REFRESH);
+  scr_refresh ();
 }
 
 /* ------------------------------------------------------------------------- *
@@ -462,7 +464,7 @@
  * XTERM_SEQ: Restore cursor: ESC 8
  */
 void
-rxvt_term::scr_cursor (int mode)
+rxvt_term::scr_cursor (cursor_mode mode) NOTHROW
 {
   screen_t *s;
 
@@ -511,7 +513,7 @@
  * XTERM_SEQ: Secondary screen: ESC [ ? 4 7 l
  */
 int
-rxvt_term::scr_change_screen (int scrn)
+rxvt_term::scr_change_screen (int scrn) NOTHROW
 {
   want_refresh = 1;
   view_start = 0;
@@ -552,7 +554,7 @@
 
 // clear WrapNext indicator, solidifying position on next line
 void
-rxvt_term::scr_do_wrap ()
+rxvt_term::scr_do_wrap () NOTHROW
 {
   if (!(screen.flags & Screen_WrapNext))
     return;
@@ -572,9 +574,9 @@
  * Change the colour for following text
  */
 void
-rxvt_term::scr_color (unsigned int color, int fgbg)
+rxvt_term::scr_color (unsigned int color, int fgbg) NOTHROW
 {
-  if (color > maxTermCOLOR)
+  if (!IN_RANGE_INC (color, minCOLOR, maxTermCOLOR))
     color = fgbg;
 
   if (fgbg == Color_fg)
@@ -588,7 +590,7 @@
  * Change the rendition style for following text
  */
 void
-rxvt_term::scr_rendition (int set, int style)
+rxvt_term::scr_rendition (int set, int style) NOTHROW
   {
     if (set)
       rstyle |= style;
@@ -605,7 +607,7 @@
  * count negative ==> scroll down
  */
 int
-rxvt_term::scr_scroll_text (int row1, int row2, int count)
+rxvt_term::scr_scroll_text (int row1, int row2, int count) NOTHROW
 {
   if (count == 0 || (row1 > row2))
     return 0;
@@ -615,40 +617,69 @@
 
   if (count > 0
       && row1 == 0
-      && row2 == nrow - 1
       && (current_screen == PRIMARY || OPTION (Opt_secondaryScroll)))
     {
-      nsaved = min (nsaved + count, saveLines);
+      top_row = max (top_row - count, -saveLines);
 
-      HOOK_INVOKE ((this, HOOK_SCROLL_BACK, DT_INT, count, DT_INT, nsaved, DT_END));
-      
+      // scroll everything up 'count' lines
       term_start = (term_start + count) % total_rows;
 
+      // sever bottommost line
+      {
+        line_t &l = ROW(row2 - count);
+        l.is_longer (0);
+        l.touch ();
+      }
+
+      // erase newly scrolled-in lines
+      for (int i = count; i--; )
+        {
+          // basically this is a slightly optimized scr_blank_screen_mem
+          // it is worth the effort on slower machines
+          line_t &l = ROW(nrow - 1 - i);
+
+          scr_blank_line (l, 0, l.l, rstyle);
+
+          l.l = 0;
+          l.f = 0;
+        }
+
+      // now copy lines below the scroll region bottom to the
+      // bottom of the screen again, so they look as if they
+      // hadn't moved.
+      for (int i = nrow; --i > row2; )
+        {
+          line_t &l1 = ROW(i - count);
+          line_t &l2 = ROW(i);
+
+          ::swap (l1, l2);
+          l2.touch ();
+        }
+      
+      // move and/or clear selection, if any
       if (selection.op && current_screen == selection.screen)
         {
           selection.beg.row  -= count;
           selection.end.row  -= count;
           selection.mark.row -= count;
 
-          if (selection.beg.row < -nsaved
-              || selection.end.row < -nsaved
-              || selection.mark.row < -nsaved)
+          if (selection.beg.row < top_row
+              || selection.end.row < top_row
+              || selection.mark.row < top_row)
             {
               CLEAR_ALL_SELECTION ();
               selection.op = SELECTION_CLEAR;
             }
         }
 
-      for (int i = count; i--; )
-        {
-          ROW(row2 - i).l = 0;
-          scr_blank_screen_mem (ROW(row2 - i), rstyle);
-        }
-      
+      // finally move the view window, if desired
       if (OPTION (Opt_scrollWithBuffer)
           && view_start != 0
-          && view_start != saveLines)
+          && view_start != -saveLines)
         scr_page (UP, count);
+
+      if (SHOULD_INVOKE (HOOK_SCROLL_BACK))
+        HOOK_INVOKE ((this, HOOK_SCROLL_BACK, DT_INT, count, DT_INT, top_row, DT_END));
     }
   else
     {
@@ -682,6 +713,8 @@
 
       min_it (count, rows);
 
+      line_t *temp_buf = row_buf + total_rows;
+
       for (int row = 0; row < rows; row++)
         {
           temp_buf [row] = ROW(row1 + (row + count + rows) % rows);
@@ -702,7 +735,7 @@
  * Add text given in <str> of length <len> to screen struct
  */
 void
-rxvt_term::scr_add_lines (const wchar_t *str, int len, int minlines)
+rxvt_term::scr_add_lines (const wchar_t *str, int len, int minlines) NOTHROW
 {
   if (len <= 0)               /* sanity */
     return;
@@ -732,7 +765,7 @@
 #ifdef DEBUG_STRICT
   assert (screen.cur.col < ncol);
   assert (screen.cur.row < nrow
-          && screen.cur.row >= -nsaved);
+          && screen.cur.row >= top_row);
 #endif
   int row = screen.cur.row;
 
@@ -788,11 +821,11 @@
 
       if (screen.flags & Screen_WrapNext)
         {
-          max_it (line->l, ncol);
-          line->is_longer (1);
-
           scr_do_wrap ();
           
+          line->l = ncol;
+          line->is_longer (1);
+
           row = screen.cur.row;
           line = &ROW(row);   /* _must_ refresh */
         }
@@ -966,7 +999,7 @@
  * XTERM_SEQ: CTRL-H
  */
 void
-rxvt_term::scr_backspace ()
+rxvt_term::scr_backspace () NOTHROW
 {
   want_refresh = 1;
 
@@ -994,7 +1027,7 @@
  * XTERM_SEQ: CTRL-I
  */
 void
-rxvt_term::scr_tab (int count, bool ht)
+rxvt_term::scr_tab (int count, bool ht) NOTHROW
 {
   int i, x;
 
@@ -1071,7 +1104,7 @@
  */
 #if ENABLE_FRILLS
 void
-rxvt_term::scr_backindex ()
+rxvt_term::scr_backindex () NOTHROW
 {
   if (screen.cur.col > 0)
     scr_gotorc (0, -1, R_RELATIVE | C_RELATIVE);
@@ -1088,7 +1121,7 @@
  */
 #if ENABLE_FRILLS
 void
-rxvt_term::scr_forwardindex ()
+rxvt_term::scr_forwardindex () NOTHROW
 {
   if (screen.cur.col < ncol - 1)
     scr_gotorc (0, 1, R_RELATIVE | C_RELATIVE);
@@ -1111,7 +1144,7 @@
  * Goto Row/Column
  */
 void
-rxvt_term::scr_gotorc (int row, int col, int relative)
+rxvt_term::scr_gotorc (int row, int col, int relative) NOTHROW
 {
   want_refresh = 1;
   ZERO_SCROLLBACK ();
@@ -1159,7 +1192,7 @@
  * direction should be UP or DN
  */
 void
-rxvt_term::scr_index (enum page_dirn direction)
+rxvt_term::scr_index (enum page_dirn direction) NOTHROW
 {
   int dirn;
 
@@ -1188,7 +1221,7 @@
  * XTERM_SEQ: Clear whole line   : ESC [ 2 K
  */
 void
-rxvt_term::scr_erase_line (int mode)
+rxvt_term::scr_erase_line (int mode) NOTHROW
 {
   unsigned int col, num;
 
@@ -1242,7 +1275,7 @@
  * XTERM_SEQ: Clear whole screen        : ESC [ 2 J
  */
 void
-rxvt_term::scr_erase_screen (int mode)
+rxvt_term::scr_erase_screen (int mode) NOTHROW
 {
   int num;
   int32_t row;
@@ -1305,22 +1338,19 @@
 
   for (; num--; row++)
     {
-      line_t &l = ROW(row);
-      l.l = 0;
-      l.is_longer (0);
-      scr_blank_screen_mem (l, rstyle);
+      scr_blank_screen_mem (ROW(row), rstyle);
       scr_blank_line (drawn_buf [row], 0, ncol, ren);
     }
 }
 
 #if ENABLE_FRILLS
 void
-rxvt_term::scr_erase_savelines ()
+rxvt_term::scr_erase_savelines () NOTHROW
 {
   want_refresh = 1;
   ZERO_SCROLLBACK ();
 
-  nsaved = 0;
+  top_row = 0;
 }
 #endif
 
@@ -1330,7 +1360,7 @@
  * XTERM_SEQ: Screen Alignment Test: ESC # 8
  */
 void
-rxvt_term::scr_E ()
+rxvt_term::scr_E () NOTHROW
 {
   rend_t fs;
 
@@ -1361,7 +1391,7 @@
  * Insert/Delete <count> lines
  */
 void
-rxvt_term::scr_insdel_lines (int count, int insdel)
+rxvt_term::scr_insdel_lines (int count, int insdel) NOTHROW
 {
   int end;
 
@@ -1391,7 +1421,7 @@
  * Insert/Delete <count> characters from the current position
  */
 void
-rxvt_term::scr_insdel_chars (int count, int insdel)
+rxvt_term::scr_insdel_chars (int count, int insdel) NOTHROW
 {
   int col, row;
   rend_t tr;
@@ -1489,7 +1519,7 @@
  * XTERM_SEQ: Set region <top> - <bot> inclusive: ESC [ <top> ; <bot> r
  */
 void
-rxvt_term::scr_scroll_region (int top, int bot)
+rxvt_term::scr_scroll_region (int top, int bot) NOTHROW
 {
   max_it (top, 0);
   min_it (bot, nrow - 1);
@@ -1509,7 +1539,7 @@
  * XTERM_SEQ: Make cursor invisible: ESC [ ? 25 l
  */
 void
-rxvt_term::scr_cursor_visible (int mode)
+rxvt_term::scr_cursor_visible (int mode) NOTHROW
 {
   want_refresh = 1;
 
@@ -1526,7 +1556,7 @@
  * XTERM_SEQ: Unset Wraparound: ESC [ ? 7 l
  */
 void
-rxvt_term::scr_autowrap (int mode)
+rxvt_term::scr_autowrap (int mode) NOTHROW
 {
   if (mode)
     screen.flags |= Screen_Autowrap;
@@ -1545,7 +1575,7 @@
  * XTERM_SEQ: Set Relative: ESC [ ? 6 l
  */
 void
-rxvt_term::scr_relative_origin (int mode)
+rxvt_term::scr_relative_origin (int mode) NOTHROW
 {
   if (mode)
     screen.flags |= Screen_Relative;
@@ -1562,7 +1592,7 @@
  * XTERM_SEQ: Set Replace mode: ESC [ ? 4 l
  */
 void
-rxvt_term::scr_insert_mode (int mode)
+rxvt_term::scr_insert_mode (int mode) NOTHROW
 {
   if (mode)
     screen.flags |= Screen_Insert;
@@ -1578,7 +1608,7 @@
  * XTERM_SEQ: Clear all tabs             : ESC [ 3 g
  */
 void
-rxvt_term::scr_set_tab (int mode)
+rxvt_term::scr_set_tab (int mode) NOTHROW
 {
   if (mode < 0)
     memset (tabs, 0, ncol * sizeof (char));
@@ -1593,7 +1623,7 @@
  * XTERM_SEQ: Normal video : ESC [ ? 5 l
  */
 void
-rxvt_term::scr_rvideo_mode (int mode)
+rxvt_term::scr_rvideo_mode (int mode) NOTHROW
 {
   XGCValues gcvalue;
 
@@ -1625,7 +1655,7 @@
  * XTERM_SEQ: Report position: ESC [ 6 n
  */
 void
-rxvt_term::scr_report_position ()
+rxvt_term::scr_report_position () NOTHROW
 {
   tt_printf ("\033[%d;%dR", screen.cur.row + 1, screen.cur.col + 1);
 }
@@ -1638,7 +1668,7 @@
  * Set font style
  */
 void
-rxvt_term::set_font_style ()
+rxvt_term::set_font_style () NOTHROW
 {
 #if 0
   switch (charsets [screen.charset])
@@ -1670,7 +1700,7 @@
  * XTERM_SEQ: Invoke G3 character set: ESC O
  */
 void
-rxvt_term::scr_charset_choose (int set)
+rxvt_term::scr_charset_choose (int set) NOTHROW
 {
   screen.charset = set;
   set_font_style ();
@@ -1686,7 +1716,7 @@
  * See set_font_style for possible values for <C>
  */
 void
-rxvt_term::scr_charset_set (int set, unsigned int ch)
+rxvt_term::scr_charset_set (int set, unsigned int ch) NOTHROW
 {
   charsets[set] = (unsigned char)ch;
   set_font_style ();
@@ -1701,7 +1731,7 @@
  * refresh matching text.
  */
 bool
-rxvt_term::scr_refresh_rend (rend_t mask, rend_t value)
+rxvt_term::scr_refresh_rend (rend_t mask, rend_t value) NOTHROW
 {
   bool found = false;
 
@@ -1731,7 +1761,7 @@
 };
 
 void
-rxvt_term::scr_expose (int x, int y, int ewidth, int eheight, bool refresh)
+rxvt_term::scr_expose (int x, int y, int ewidth, int eheight, bool refresh) NOTHROW
 {
   int i;
   row_col_t rc[RC_COUNT];
@@ -1764,8 +1794,10 @@
   for (i = rc[PART_BEG].row; i <= rc[PART_END].row; i++)
     fill_text (&drawn_buf[i].t[rc[PART_BEG].col], 0, rc[PART_END].col - rc[PART_BEG].col + 1);
 
+  num_scr_allow = 0;
+
   if (refresh)
-    scr_refresh (SLOW_REFRESH);
+    scr_refresh ();
 }
 
 /* ------------------------------------------------------------------------- */
@@ -1773,7 +1805,7 @@
  * Refresh the entire screen
  */
 void
-rxvt_term::scr_touch (bool refresh)
+rxvt_term::scr_touch (bool refresh) NOTHROW
 {
   scr_expose (0, 0, width, height, refresh);
 }
@@ -1783,24 +1815,10 @@
  * Move the display so that the line represented by scrollbar value Y is at
  * the top of the screen
  */
-int
-rxvt_term::scr_move_to (int y, int len)
+void
+rxvt_term::scr_move_to (int y, int len) NOTHROW
 {
-  long p = 0;
-  unsigned int oldviewstart;
-
-  oldviewstart = view_start;
-
-  if (y < len)
-    {
-      p = (nrow + nsaved) * (len - y) / len;
-      p -= (long) (nrow - 1);
-      p = max (p, 0);
-    }
-
-  view_start = (unsigned int)min (p, nsaved);
-
-  return scr_changeview (oldviewstart);
+  scr_changeview ((top_row - nrow) * (len - y) / len + (nrow - 1));
 }
 
 /* ------------------------------------------------------------------------- */
@@ -1808,45 +1826,36 @@
  * Page the screen up/down nlines
  * direction should be UP or DN
  */
-int
-rxvt_term::scr_page (enum page_dirn direction, int nlines)
+bool
+rxvt_term::scr_page (enum page_dirn direction, int nlines) NOTHROW
 {
-  int n;
-  unsigned int oldviewstart;
-
-  oldviewstart = view_start;
+  int new_view_start =
+    direction == UP ? view_start - nlines
+                    : view_start + nlines;
 
-  if (direction == UP)
-    {
-      n = view_start + nlines;
-      view_start = min (n, nsaved);
-    }
-  else
-    {
-      n = view_start - nlines;
-      view_start = max (n, 0);
-    }
-
-  return scr_changeview (oldviewstart);
+  return scr_changeview (new_view_start);
 }
 
-int
-rxvt_term::scr_changeview (unsigned int oldviewstart)
+bool
+rxvt_term::scr_changeview (int new_view_start) NOTHROW
 {
-  if (view_start != oldviewstart)
-    {
-      HOOK_INVOKE ((this, HOOK_VIEW_CHANGE, DT_INT, view_start, DT_END));
+  clamp_it (new_view_start, top_row, 0);
 
-      want_refresh = 1;
-      num_scr -= (view_start - oldviewstart);
-    }
+  if (new_view_start == view_start)
+    return false;
+
+  num_scr += new_view_start - view_start;
+  view_start = new_view_start;
+  want_refresh = 1;
 
-  return (int)view_start - (int)oldviewstart;
+  HOOK_INVOKE ((this, HOOK_VIEW_CHANGE, DT_INT, view_start, DT_END));
+
+  return true;
 }
 
 /* ------------------------------------------------------------------------- */
 void
-rxvt_term::scr_bell ()
+rxvt_term::scr_bell () NOTHROW
 {
 #ifndef NO_BELL
 
@@ -1860,6 +1869,7 @@
   if (OPTION (Opt_visualBell))
     {
       scr_rvideo_mode (!rvideo); /* refresh also done */
+      display->flush ();
       rxvt_usleep (VISUAL_BELL_DURATION);
       scr_rvideo_mode (!rvideo); /* refresh also done */
     }
@@ -1872,7 +1882,7 @@
 /* ------------------------------------------------------------------------- */
 /* ARGSUSED */
 void
-rxvt_term::scr_printscreen (int fullhist)
+rxvt_term::scr_printscreen (int fullhist) NOTHROW
 {
 #ifdef PRINTPIPE
   int nrows, row_start;
@@ -1883,13 +1893,13 @@
 
   if (fullhist)
     {
-      nrows = nrow + nsaved;
-      row_start = -nsaved;
+      nrows = nrow - top_row;
+      row_start = top_row;
     }
   else
     {
       nrows = nrow;
-      row_start = -view_start;
+      row_start = view_start;
     }
 
   wctomb (0, 0);
@@ -1931,7 +1941,7 @@
  * screen.text/screen.rend contain what the screen will change to.
  */
 void
-rxvt_term::scr_refresh (unsigned char refresh_type)
+rxvt_term::scr_refresh () NOTHROW
 {
   unsigned char must_clear, /* use draw_string not draw_image_string     */
                 showcursor; /* show the cursor                           */
@@ -2027,7 +2037,7 @@
     setoldcursor = 0;
     if (ocrow != -1)
       {
-        if (screen.cur.row + view_start != ocrow
+        if (screen.cur.row - view_start != ocrow
             || screen.cur.col != oldcursor.col)
           {
             if (ocrow < nrow
@@ -2045,11 +2055,11 @@
 
     if (setoldcursor)
       {
-        if (screen.cur.row + view_start >= nrow)
+        if (screen.cur.row - view_start >= nrow)
           oldcursor.row = -1;
         else
           {
-            oldcursor.row = screen.cur.row + view_start;
+            oldcursor.row = screen.cur.row - view_start;
             oldcursor.col = screen.cur.col;
           }
       }
@@ -2065,7 +2075,6 @@
    * D: CopyArea pass - very useful for slower links
    *    This has been deliberately kept simple.
    */
-  i = num_scr;
   if (!display->is_local
       && refresh_type == FAST_REFRESH && num_scr_allow && num_scr
       && abs (num_scr) < nrow && !must_clear)
@@ -2073,6 +2082,7 @@
       int16_t nits;
       int j;
       int len, wlen;
+      dLocal (int, num_scr);
 
       j = nrow;
       wlen = len = -1;
@@ -2081,7 +2091,7 @@
         {
           if (row + i >= 0 && row + i < nrow && row + i != ocrow)
             {
-              line_t s  = ROW(row - view_start);
+              line_t s  = ROW(view_start + row);
               line_t d  = drawn_buf[row];
               line_t d2 = drawn_buf[row + i];
 
@@ -2129,8 +2139,8 @@
    */
   for (row = 0; row < nrow; row++)
     {
-      text_t *stp = ROW(row - view_start).t;
-      rend_t *srp = ROW(row - view_start).r;
+      text_t *stp = ROW(view_start + row).t;
+      rend_t *srp = ROW(view_start + row).r;
       text_t *dtp = drawn_buf[row].t;
       rend_t *drp = drawn_buf[row].r;
 
@@ -2377,27 +2387,24 @@
    */
   scr_reverse_selection ();
 
-  if (refresh_type & SMOOTH_REFRESH)
-    XFlush (display->display);
-
   num_scr = 0;
   num_scr_allow = 1;
 }
 
 void
-rxvt_term::scr_remap_chars (line_t &l)
+rxvt_term::scr_remap_chars (line_t &l) NOTHROW
 {
   if (!l.t)
     return;
 
-  l.touch (); // maybe a bit of an overkill, but its not performance-relevant
+  l.touch (); // maybe a bit of an overkill, but it's not performance-relevant
 
   for (int i = ncol; i--; )
     l.r[i] = SET_FONT (l.r[i], FONTSET (l.r[i])->find_font (l.t[i]));
 }
 
 void
-rxvt_term::scr_remap_chars ()
+rxvt_term::scr_remap_chars () NOTHROW
 {
   for (int i = total_rows; i--; )
     scr_remap_chars (row_buf [i]);
@@ -2410,7 +2417,7 @@
 }
 
 void
-rxvt_term::scr_recolour ()
+rxvt_term::scr_recolour () NOTHROW
 {
   if (1
 #if TRANSPARENT
@@ -2441,7 +2448,7 @@
 
 /* ------------------------------------------------------------------------- */
 void
-rxvt_term::scr_clear (bool really)
+rxvt_term::scr_clear (bool really) NOTHROW
 {
   if (!mapped)
     return;
@@ -2453,57 +2460,72 @@
     XClearWindow (display->display, vt);
 }
 
+void
+rxvt_term::scr_xor_rect (int beg_row, int beg_col, int end_row, int end_col, rend_t rstyle1, rend_t rstyle2) NOTHROW
+{
+  int view_end = view_start + nrow;
+  int row, col;
+
+  for (row = max (beg_row, view_start); row <= min (end_row, view_end); row++)
+    {
+      text_t *stp = ROW(row).t;
+      rend_t *srp = ROW(row).r;
+
+      for (col = beg_col; col < end_col; col++)
+        srp[col] ^= rstyle1;
+
+      while (col-- > beg_col && (stp[col] == NOCHAR || unicode::is_space (stp[col])))
+        srp[col] ^= rstyle2;
+
+      if (++col < end_col)
+        srp[col] ^= rstyle2;
+    }
+}
+
+void
+rxvt_term::scr_xor_span (int beg_row, int beg_col, int end_row, int end_col, rend_t rstyle) NOTHROW
+{
+  int view_end = view_start + nrow;
+  int row, col;
+
+  if (beg_row >= view_start)
+    {
+      col = beg_col;
+      row = beg_row;
+    }
+  else
+    {
+      col = 0;
+      row = view_start;
+    }
+
+  for (; row < min (end_row, view_end); row++, col = 0)
+    for (rend_t *srp = ROW(row).r; col < ncol; col++)
+      srp[col] ^= rstyle;
+
+  if (row == end_row)
+    for (rend_t *srp = ROW(row).r; col < end_col; col++)
+      srp[col] ^= rstyle;
+}
+
 /* ------------------------------------------------------------------------- */
 void
-rxvt_term::scr_reverse_selection ()
+rxvt_term::scr_reverse_selection () NOTHROW
 {
   if (selection.op
       && current_screen == selection.screen
-      && selection.end.row >= -view_start)
+      && selection.end.row >= view_start)
     {
-      int view_end = -view_start + nrow;
-      int row, col;
-
 #if ENABLE_FRILLS
       if (selection.rect)
-        {
-          for (row = max (selection.beg.row, -view_start); row <= min (selection.end.row, view_end); row++)
-            {
-              text_t *stp = ROW(row).t;
-              rend_t *srp = ROW(row).r;
-
-              for (col = selection.beg.col; col < selection.end.col; col++)
-                srp[col] ^= RS_RVid;
-
-              while (col-- > selection.beg.col && (stp[col] == NOCHAR || unicode::is_space (stp[col])))
-                srp[col] ^= RS_RVid | RS_Uline;
-
-              if (++col < selection.end.col)
-                srp[col] ^= RS_RVid | RS_Uline;
-            }
-        }
+        scr_xor_rect (selection.beg.row, selection.beg.col,
+                      selection.end.row, selection.end.col,
+                      RS_RVid, RS_RVid | RS_Uline);
       else
 #endif
-        {
-          if (selection.beg.row >= -view_start)
-            {
-              col = selection.beg.col;
-              row = selection.beg.row;
-            }
-          else
-            {
-              col = 0;
-              row = -view_start;
-            }
-
-          for (; row < min (selection.end.row, view_end); row++, col = 0)
-            for (rend_t *srp = ROW(row).r; col < ncol; col++)
-              srp[col] ^= RS_RVid;
-
-          if (row == selection.end.row)
-            for (rend_t *srp = ROW(row).r; col < selection.end.col; col++)
-              srp[col] ^= RS_RVid;
-        }
+        scr_xor_span (selection.beg.row, selection.beg.col,
+                      selection.end.row, selection.end.col,
+                      RS_RVid);
     }
 }
 
@@ -2514,7 +2536,7 @@
  */
 #if 0
 void
-rxvt_term::scr_dump (int fd)
+rxvt_term::scr_dump (int fd) NOTHROW
 {
   int             row, wrote;
   unsigned int    width, towrite;
@@ -2543,7 +2565,7 @@
  *                           CHARACTER SELECTION                             *
  * ------------------------------------------------------------------------- */
 void
-rxvt_term::selection_check (int check_more)
+rxvt_term::selection_check (int check_more) NOTHROW
 {
   row_col_t pos;
 
@@ -2551,9 +2573,9 @@
     return;
 
   pos.row = pos.col = 0;
-  if (!IN_RANGE_EXC (selection.beg.row, -nsaved, nrow)
-      || !IN_RANGE_EXC (selection.mark.row, -nsaved, nrow)
-      || !IN_RANGE_EXC (selection.end.row, -nsaved, nrow)
+  if (!IN_RANGE_EXC (selection.beg.row, top_row, nrow)
+      || !IN_RANGE_EXC (selection.mark.row, top_row, nrow)
+      || !IN_RANGE_EXC (selection.end.row, top_row, nrow)
       || (check_more == 1
           && current_screen == selection.screen
           && !ROWCOL_IS_BEFORE (screen.cur, selection.beg)
@@ -2574,7 +2596,7 @@
  * Paste a selection direct to the command fd
  */
 void
-rxvt_term::paste (char *data, unsigned int len)
+rxvt_term::paste (char *data, unsigned int len) NOTHROW
 {
   /* convert normal newline chars into common keyboard Return key sequence */
   for (unsigned int i = 0; i < len; i++)
@@ -2590,7 +2612,7 @@
  * EXT: SelectionNotify
  */
 void
-rxvt_term::selection_paste (Window win, Atom prop, bool delete_prop)
+rxvt_term::selection_paste (Window win, Atom prop, bool delete_prop) NOTHROW
 {
   if (prop == None)         /* check for failed XConvertSelection */
     {
@@ -2752,7 +2774,7 @@
 }
 
 void
-rxvt_term::incr_cb (time_watcher &w)
+rxvt_term::incr_cb (time_watcher &w) NOTHROW
 {
   selection_wait = Sel_none;
 
@@ -2763,7 +2785,7 @@
 }
 
 void
-rxvt_term::selection_property (Window win, Atom prop)
+rxvt_term::selection_property (Window win, Atom prop) NOTHROW
 {
   if (prop == None || selection_wait != Sel_incr)
     return;
@@ -2782,12 +2804,9 @@
  * EXT: button 2 release
  */
 void
-rxvt_term::selection_request (Time tm, int x, int y)
+rxvt_term::selection_request (Time tm, int selnum) NOTHROW
 {
-  if (x < 0 || x >= width || y < 0 || y >= height)
-    return;                 /* outside window */
-
-  if (selection.text)
+  if (selection.text && selnum == Sel_Primary)
     { /* internal selection */
       char *str = rxvt_wcstombs (selection.text, selection.len);
       paste (str, strlen (str));
@@ -2796,23 +2815,18 @@
     }
   else
     {
-      int i;
-
       selection_request_time = tm;
       selection_wait = Sel_normal;
 
-      for (i = Sel_Primary; i <= Sel_Clipboard; i++)
-        {
 #if X_HAVE_UTF8_STRING
-          selection_type = Sel_UTF8String;
-          if (selection_request_other (xa[XA_UTF8_STRING], i))
-            return;
+      selection_type = Sel_UTF8String;
+      if (selection_request_other (xa[XA_UTF8_STRING], selnum))
+	return;
 #else
-          selection_type = Sel_CompoundText;
-          if (selection_request_other (xa[XA_COMPOUND_TEXT], i))
-            return;
+      selection_type = Sel_CompoundText;
+      if (selection_request_other (xa[XA_COMPOUND_TEXT], selnum))
+	return;
 #endif
-        }
     }
 
   selection_wait = Sel_none;       /* don't loop in selection_paste () */
@@ -2820,7 +2834,7 @@
 }
 
 int
-rxvt_term::selection_request_other (Atom target, int selnum)
+rxvt_term::selection_request_other (Atom target, int selnum) NOTHROW
 {
   Atom sel;
 
@@ -2849,7 +2863,7 @@
  * EXT: SelectionClear
  */
 void
-rxvt_term::selection_clear ()
+rxvt_term::selection_clear () NOTHROW
 {
   want_refresh = 1;
   free (selection.text);
@@ -2994,7 +3008,7 @@
 }
 
 bool
-rxvt_term::selection_grab (Time tm)
+rxvt_term::selection_grab (Time tm) NOTHROW
 {
   selection_time = tm;
 
@@ -3005,7 +3019,10 @@
       return true;
     }
   else
-    return false;
+    {
+      selection_clear ();
+      return false;
+    }
 
 #if 0
   XTextProperty ct;
@@ -3024,16 +3041,25 @@
  * EXT: button 1 press
  */
 void
-rxvt_term::selection_click (int clicks, int x, int y)
+rxvt_term::selection_click (int clicks, int x, int y) NOTHROW
 {
   clicks = ((clicks - 1) % 3) + 1;
   selection.clicks = clicks;       /* save clicks so extend will work */
 
+  if (clicks == 2 && !selection.rect
+      && HOOK_INVOKE ((this, HOOK_SEL_EXTEND, DT_END)))
+    {
+      MEvent.clicks = 1; // what a mess
+      selection.screen = current_screen;
+      selection.op = SELECTION_CONT;
+      return;
+    }
+
   selection_start_colrow (Pixel2Col (x), Pixel2Row (y));
 
   if (clicks == 2 || clicks == 3)
     selection_extend_colrow (selection.mark.col,
-                             selection.mark.row + view_start,
+                             selection.mark.row - view_start,
                              0, /* button 3     */
                              1, /* button press */
                              0);        /* click change */
@@ -3044,14 +3070,14 @@
  * Mark a selection at the specified col/row
  */
 void
-rxvt_term::selection_start_colrow (int col, int row)
+rxvt_term::selection_start_colrow (int col, int row) NOTHROW
 {
   want_refresh = 1;
 
-  selection.mark.row = row - view_start;
+  selection.mark.row = row + view_start;
   selection.mark.col = col;
 
-  selection.mark.row = clamp (selection.mark.row, -nsaved, nrow - 1);
+  selection.mark.row = clamp (selection.mark.row, top_row, nrow - 1);
   selection.mark.col = clamp (selection.mark.col,       0, ncol - 1);
 
   while (selection.mark.col > 0
@@ -3080,7 +3106,7 @@
 #define DELIMIT_REND(x)        1
 
 void
-rxvt_term::selection_delimit_word (enum page_dirn dirn, const row_col_t *mark, row_col_t *ret)
+rxvt_term::selection_delimit_word (enum page_dirn dirn, const row_col_t *mark, row_col_t *ret) NOTHROW
 {
   int col, row, dirnadd, tcol, trow, w1, w2;
   row_col_t bound;
@@ -3089,7 +3115,7 @@
 
   if (dirn == UP)
     {
-      bound.row = - nsaved - 1;
+      bound.row = top_row - 1;
       bound.col = 0;
       dirnadd = -1;
     }
@@ -3164,7 +3190,7 @@
  * flag == 2 ==> button 3 motion
  */
 void
-rxvt_term::selection_extend (int x, int y, int flag)
+rxvt_term::selection_extend (int x, int y, int flag) NOTHROW
 {
   int col = clamp (Pixel2Col (x), 0, ncol);
   int row = clamp (Pixel2Row (y), 0, nrow - 1);
@@ -3177,7 +3203,7 @@
   */
   if (((selection.clicks % 3) == 1) && !flag
       && (col == selection.mark.col
-          && (row == selection.mark.row + view_start)))
+          && (row == selection.mark.row - view_start)))
     {
       /* select nothing */
       selection.beg.row = selection.end.row = 0;
@@ -3200,7 +3226,7 @@
  * Extend the selection to the specified col/row
  */
 void
-rxvt_term::selection_extend_colrow (int32_t col, int32_t row, int button3, int buttonpress, int clickchange)
+rxvt_term::selection_extend_colrow (int32_t col, int32_t row, int button3, int buttonpress, int clickchange) NOTHROW
 {
   row_col_t pos;
   enum {
@@ -3242,7 +3268,7 @@
     }
 
   pos.col = col;
-  pos.row = row - view_start;
+  pos.row = view_start + row;
 
   /*
    * This is mainly xterm style selection with a couple of differences, mainly
@@ -3333,11 +3359,8 @@
       if (ROWCOL_IS_AFTER (selection.end, selection.beg))
         selection.end.col--;
 
-      if (!HOOK_INVOKE ((this, HOOK_SEL_EXTEND, DT_END)))
-        {
-          selection_delimit_word (UP, &selection.beg, &selection.beg);
-          selection_delimit_word (DN, &selection.end, &selection.end);
-        }
+      selection_delimit_word (UP, &selection.beg, &selection.beg);
+      selection_delimit_word (DN, &selection.end, &selection.end);
     }
   else if (selection.clicks == 3)
     {
@@ -3399,7 +3422,7 @@
 
 #if ENABLE_FRILLS
 void
-rxvt_term::selection_remove_trailing_spaces ()
+rxvt_term::selection_remove_trailing_spaces () NOTHROW
 {
   int32_t end_col, end_row;
   text_t *stp;
@@ -3447,7 +3470,7 @@
  * EXT: button 3 double click
  */
 void
-rxvt_term::selection_rotate (int x, int y)
+rxvt_term::selection_rotate (int x, int y) NOTHROW
 {
   selection.clicks = selection.clicks % 3 + 1;
   selection_extend_colrow (Pixel2Col (x), Pixel2Row (y), 1, 0, 1);
@@ -3459,7 +3482,7 @@
  * EXT: SelectionRequest
  */
 void
-rxvt_term::selection_send (const XSelectionRequestEvent &rq)
+rxvt_term::selection_send (const XSelectionRequestEvent &rq) NOTHROW
 {
   XSelectionEvent ev;
   dDisp;
@@ -3597,7 +3620,7 @@
  * return col/row values corresponding to x/y pixel values
  */
 void
-rxvt_term::pixel_position (int *x, int *y)
+rxvt_term::pixel_position (int *x, int *y) NOTHROW
 {
   *x = Pixel2Col (*x);
   /* max_it (*x, 0); min_it (*x, (int)ncol - 1); */
@@ -3608,7 +3631,7 @@
 /* ------------------------------------------------------------------------- */
 #ifdef USE_XIM
 void
-rxvt_term::im_set_position (XPoint &pos)
+rxvt_term::im_set_position (XPoint &pos) NOTHROW
 {
   XWindowAttributes xwa;
 
@@ -3621,7 +3644,7 @@
 
 #if ENABLE_OVERLAY
 void
-rxvt_term::scr_overlay_new (int x, int y, int w, int h)
+rxvt_term::scr_overlay_new (int x, int y, int w, int h) NOTHROW
 {
   if (nrow < 1 || ncol < 1)
     return;
@@ -3676,7 +3699,7 @@
 }
 
 void
-rxvt_term::scr_overlay_off ()
+rxvt_term::scr_overlay_off () NOTHROW
 {
   if (!ov_text)
     return;
@@ -3694,7 +3717,7 @@
 }
 
 void
-rxvt_term::scr_overlay_set (int x, int y, text_t text, rend_t rend)
+rxvt_term::scr_overlay_set (int x, int y, text_t text, rend_t rend) NOTHROW
 {
   if (!ov_text || x >= ov_w - 2 || y >= ov_h - 2)
     return;
@@ -3706,14 +3729,14 @@
 }
 
 void
-rxvt_term::scr_overlay_set (int x, int y, const char *s)
+rxvt_term::scr_overlay_set (int x, int y, const char *s) NOTHROW
 {
   while (*s)
     scr_overlay_set (x++, y, *s++);
 }
 
 void
-rxvt_term::scr_overlay_set (int x, int y, const wchar_t *s)
+rxvt_term::scr_overlay_set (int x, int y, const wchar_t *s) NOTHROW
 {
   while (*s)
     {
@@ -3729,7 +3752,7 @@
 }
 
 void
-rxvt_term::scr_swap_overlay ()
+rxvt_term::scr_swap_overlay () NOTHROW
 {
   if (!ov_text)
     return;
@@ -3740,8 +3763,8 @@
       text_t *t1 = ov_text[y];
       rend_t *r1 = ov_rend[y];
 
-      text_t *t2 = ROW(y + ov_y - view_start).t + ov_x;
-      rend_t *r2 = ROW(y + ov_y - view_start).r + ov_x;
+      text_t *t2 = ROW(y + ov_y + view_start).t + ov_x;
+      rend_t *r2 = ROW(y + ov_y + view_start).r + ov_x;
 
       for (int x = ov_w; x--; )
         {