[Emacs-diffs] Changes to emacs/src/xdisp.c,v

[Chong Yidong]

CVSROOT:        /sources/emacs
Module name:    emacs
Changes by:     Chong Yidong <cyd>      08/06/24 18:00:21

Index: xdisp.c
===================================================================
RCS file: /sources/emacs/emacs/src/xdisp.c,v
retrieving revision 1.1220
retrieving revision 1.1221
diff -u -b -r1.1220 -r1.1221
--- xdisp.c     14 Jun 2008 19:12:44 -0000      1.1220
+++ xdisp.c     24 Jun 2008 18:00:20 -0000      1.1221
@@ -420,7 +420,7 @@
 /* Nonzero means truncate lines in all windows less wide than the
    frame.  */
 
-int truncate_partial_width_windows;
+Lisp_Object Vtruncate_partial_width_windows;
 
 /* A flag to control how to display unibyte 8-bit character.  */
 
@@ -2634,19 +2634,27 @@
     it->tab_width = 8;
 
   /* Are lines in the display truncated?  */
-  it->truncate_lines_p
-    = (base_face_id != DEFAULT_FACE_ID
+  if (base_face_id != DEFAULT_FACE_ID
        || XINT (it->w->hscroll)
-       || (truncate_partial_width_windows
-          && !WINDOW_FULL_WIDTH_P (it->w))
-       || !NILP (current_buffer->truncate_lines));
+      || (! WINDOW_FULL_WIDTH_P (it->w)
+         && ((!NILP (Vtruncate_partial_width_windows)
+              && !INTEGERP (Vtruncate_partial_width_windows))
+             || (INTEGERP (Vtruncate_partial_width_windows)
+                 && (WINDOW_TOTAL_COLS (it->w)
+                     < XINT (Vtruncate_partial_width_windows))))))
+    it->line_wrap = TRUNCATE;
+  else if (NILP (current_buffer->truncate_lines))
+    it->line_wrap = NILP (current_buffer->word_wrap)
+      ? WINDOW_WRAP : WORD_WRAP;
+  else
+    it->line_wrap = TRUNCATE;
 
   /* Get dimensions of truncation and continuation glyphs.  These are
      displayed as fringe bitmaps under X, so we don't need them for such
      frames.  */
   if (!FRAME_WINDOW_P (it->f))
     {
-      if (it->truncate_lines_p)
+      if (it->line_wrap == TRUNCATE)
        {
          /* We will need the truncation glyph.  */
          xassert (it->glyph_row == NULL);
@@ -2696,7 +2704,7 @@
         for window-based redisplay.  */
       if (!FRAME_WINDOW_P (it->f))
        {
-         if (it->truncate_lines_p)
+         if (it->line_wrap == TRUNCATE)
            it->last_visible_x -= it->truncation_pixel_width;
          else
            it->last_visible_x -= it->continuation_pixel_width;
@@ -2769,7 +2777,7 @@
 
   /* Don't reseat to previous visible line start if current start
      position is in a string or image.  */
-  if (it->method == GET_FROM_BUFFER && !it->truncate_lines_p)
+  if (it->method == GET_FROM_BUFFER && it->line_wrap != TRUNCATE)
     {
       int start_at_line_beg_p;
       int first_y = it->current_y;
@@ -2794,7 +2802,7 @@
             taken us to the start of the continuation line but to the
             end of the continued line.  */
          if (it->current_x > 0
-             && !it->truncate_lines_p /* Lines are continued.  */
+             && it->line_wrap != TRUNCATE /* Lines are continued.  */
              && (/* And glyph doesn't fit on the line.  */
                  new_x > it->last_visible_x
                  /* Or it fits exactly and we're on a window
@@ -5432,6 +5440,7 @@
        pos = --IT_CHARPOS (it2);
        --IT_BYTEPOS (it2);
        it2.sp = 0;
+       it2.string_from_display_prop_p = 0;
        if (handle_display_prop (&it2) == HANDLED_RETURN
            && !NILP (val = get_char_property_and_overlay
                      (make_number (pos), Qdisplay, Qnil, &overlay))
@@ -5582,6 +5591,7 @@
   IT_STRING_CHARPOS (*it) = -1;
   IT_STRING_BYTEPOS (*it) = -1;
   it->string = Qnil;
+  it->string_from_display_prop_p = 0;
   it->method = GET_FROM_BUFFER;
   it->object = it->w->buffer;
   it->area = TEXT_AREA;
@@ -6643,11 +6653,20 @@
 {
   enum move_it_result result = MOVE_UNDEFINED;
   struct glyph_row *saved_glyph_row;
+  struct it wrap_it, atpos_it;
+  int may_wrap = 0;
 
   /* Don't produce glyphs in produce_glyphs.  */
   saved_glyph_row = it->glyph_row;
   it->glyph_row = NULL;
 
+  /* Use wrap_it to save a copy of IT wherever a word wrap could
+     occur.  Use atpos_it to save a copy of IT at the desired
+     position, if found, so that we can scan ahead and check if the
+     word later overshoots the window edge.  */
+  wrap_it.sp = -1;
+  atpos_it.sp = -1;
+
 #define BUFFER_POS_REACHED_P()                                 \
   ((op & MOVE_TO_POS) != 0                                     \
    && BUFFERP (it->object)                                     \
@@ -6667,35 +6686,76 @@
          && it->method == GET_FROM_BUFFER
          && IT_CHARPOS (*it) > to_charpos)
        {
+         if (it->line_wrap == WORD_WRAP)
+           {
+             /* If wrap_it is valid, the current position might be in
+                a word that is wrapped to the next line, so continue
+                to see if that happens.  */
+             if (wrap_it.sp < 0)
+               {
+                 result = MOVE_POS_MATCH_OR_ZV;
+                 break;
+               }
+             if (atpos_it.sp < 0)
+               atpos_it = *it;
+           }
+         else
+           {
          result = MOVE_POS_MATCH_OR_ZV;
          break;
        }
+       }
 
       /* Stop when ZV reached.
          We used to stop here when TO_CHARPOS reached as well, but that is
          too soon if this glyph does not fit on this line.  So we handle it
          explicitly below.  */
-      if (!get_next_display_element (it)
-         || (it->truncate_lines_p
-             && BUFFER_POS_REACHED_P ()))
+      if (!get_next_display_element (it))
        {
          result = MOVE_POS_MATCH_OR_ZV;
          break;
        }
 
-      /* The call to produce_glyphs will get the metrics of the
-        display element IT is loaded with.  We record in x the
-        x-position before this display element in case it does not
-        fit on the line.  */
-      x = it->current_x;
-
-      /* Remember the line height so far in case the next element doesn't
-        fit on the line.  */
-      if (!it->truncate_lines_p)
+      if (it->line_wrap == TRUNCATE)
        {
+         if (BUFFER_POS_REACHED_P ())
+           {
+             result = MOVE_POS_MATCH_OR_ZV;
+             break;
+           }
+       }
+      else
+       {
+         /* Remember the line height so far in case the next element
+            doesn't fit on the line.  */
          ascent = it->max_ascent;
          descent = it->max_descent;
+
+         if (it->line_wrap == WORD_WRAP)
+           {
+             if (it->what == IT_CHARACTER
+                 && (it->c == ' ' || it->c == '\t'))
+               may_wrap = 1;
+             else if (may_wrap)
+               {
+                 /* We are done if the position is already found.  */
+                 if (atpos_it.sp >= 0)
+                   {
+                     *it = atpos_it;
+                     atpos_it.sp = -1;
+                     goto buffer_pos_reached;
+                   }
+                 wrap_it = *it;
+                 may_wrap = 0;
        }
+           }
+       }
+
+      /* The call to produce_glyphs will get the metrics of the
+        display element IT is loaded with.  Record the x-position
+        before this display element, in case it doesn't fit on the
+        line.  */
+      x = it->current_x;
 
       PRODUCE_GLYPHS (it);
 
@@ -6740,13 +6800,24 @@
              if ((op & MOVE_TO_X) && new_x > to_x)
                {
                  if (BUFFER_POS_REACHED_P ())
+                   {
+                     if (it->line_wrap == WORD_WRAP)
+                       {
+                         if (wrap_it.sp < 0)
+                           goto buffer_pos_reached;
+                         if (atpos_it.sp < 0)
+                           atpos_it = *it;
+                       }
+                     else
                    goto buffer_pos_reached;
+                   }
                  it->current_x = x;
                  result = MOVE_X_REACHED;
                  break;
                }
-             else if (/* Lines are continued.  */
-                      !it->truncate_lines_p
+
+             if (/* Lines are continued.  */
+                 it->line_wrap != TRUNCATE
                       && (/* And glyph doesn't fit on the line.  */
                           new_x > it->last_visible_x
                           /* Or it fits exactly and we're on a window
@@ -6811,24 +6882,37 @@
                      it->max_descent = descent;
                    }
 
+                 if (wrap_it.sp >= 0)
+                   {
+                     *it = wrap_it;
+                     atpos_it.sp = -1;
+                   }
+
                  TRACE_MOVE ((stderr, "move_it_in: continued at %d\n",
                               IT_CHARPOS (*it)));
                  result = MOVE_LINE_CONTINUED;
                  break;
                }
-             else if (BUFFER_POS_REACHED_P ())
+
+             if (BUFFER_POS_REACHED_P ())
+               {
+                 if (it->line_wrap == WORD_WRAP)
+                   {
+                     if (wrap_it.sp < 0)
                goto buffer_pos_reached;
-             else if (new_x > it->first_visible_x)
+                     if (atpos_it.sp < 0)
+                       atpos_it = *it;
+                   }
+                 else
+                   goto buffer_pos_reached;
+               }
+
+             if (new_x > it->first_visible_x)
                {
                  /* Glyph is visible.  Increment number of glyphs that
                     would be displayed.  */
                  ++it->hpos;
                }
-             else
-               {
-                 /* Glyph is completely off the left margin of the display
-                    area.  Nothing to do.  */
-               }
            }
 
          if (result != MOVE_UNDEFINED)
@@ -6867,7 +6951,7 @@
 
       /* Stop if lines are truncated and IT's current x-position is
         past the right edge of the window now.  */
-      if (it->truncate_lines_p
+      if (it->line_wrap == TRUNCATE
          && it->current_x >= it->last_visible_x)
        {
 #ifdef HAVE_WINDOW_SYSTEM
@@ -6893,6 +6977,11 @@
 
 #undef BUFFER_POS_REACHED_P
 
+  /* If we scanned beyond to_pos and didn't find a point to wrap at,
+     return iterator at to_pos.  */
+  if (atpos_it.sp >= 0)
+    *it = atpos_it;
+
   /* Restore the iterator settings altered at the beginning of this
      function.  */
   it->glyph_row = saved_glyph_row;
@@ -8555,7 +8644,7 @@
       max_height = min (total_height, max_height);
 
       /* Find out the height of the text in the window.  */
-      if (it.truncate_lines_p)
+      if (it.line_wrap == TRUNCATE)
        height = 1;
       else
        {
@@ -15997,7 +16086,8 @@
       && it->glyph_row->displays_text_p
       && face->box == FACE_NO_BOX
       && face->background == FRAME_BACKGROUND_PIXEL (f)
-      && !face->stipple)
+      && !face->stipple
+      && it->line_wrap != WORD_WRAP)
     return;
 
   /* Set the glyph row flag indicating that the face of the last glyph
@@ -16212,6 +16302,11 @@
 {
   struct glyph_row *row = it->glyph_row;
   Lisp_Object overlay_arrow_string;
+  struct it wrap_it;
+  int may_wrap = 0, wrap_x;
+  int wrap_row_used = -1, wrap_row_ascent, wrap_row_height;
+  int wrap_row_phys_ascent, wrap_row_phys_height;
+  int wrap_row_extra_line_spacing;
 
   /* We always start displaying at hpos zero even if hscrolled.  */
   xassert (it->hpos == 0 && it->current_x == 0);
@@ -16306,12 +16401,31 @@
 
       /* Remember the line height so far in case the next element doesn't
         fit on the line.  */
-      if (!it->truncate_lines_p)
+      if (it->line_wrap != TRUNCATE)
        {
          ascent = it->max_ascent;
          descent = it->max_descent;
          phys_ascent = it->max_phys_ascent;
          phys_descent = it->max_phys_descent;
+
+         if (it->line_wrap == WORD_WRAP && it->area == TEXT_AREA)
+           {
+             if (it->what == IT_CHARACTER
+                 && (it->c == ' ' || it->c == '\t'))
+               may_wrap = 1;
+             else if (may_wrap)
+               {
+                 wrap_it = *it;
+                 wrap_x = x;
+                 wrap_row_used = row->used[TEXT_AREA];
+                 wrap_row_ascent = row->ascent;
+                 wrap_row_height = row->height;
+                 wrap_row_phys_ascent = row->phys_ascent;
+                 wrap_row_phys_height = row->phys_height;
+                 wrap_row_extra_line_spacing = row->extra_line_spacing;
+                 may_wrap = 0;
+               }
+           }
        }
 
       PRODUCE_GLYPHS (it);
@@ -16371,7 +16485,7 @@
              new_x = x + glyph->pixel_width;
 
              if (/* Lines are continued.  */
-                 !it->truncate_lines_p
+                 it->line_wrap != TRUNCATE
                  && (/* Glyph doesn't fit on the line.  */
                      new_x > it->last_visible_x
                      /* Or it fits exactly on a window system frame.  */
@@ -16412,6 +16526,8 @@
                                }
                            }
 #endif /* HAVE_WINDOW_SYSTEM */
+                         if (wrap_row_used > 0)
+                           goto back_to_wrap;
                        }
                    }
                  else if (CHAR_GLYPH_PADDING_P (*glyph)
@@ -16439,6 +16555,26 @@
                      it->max_phys_ascent = phys_ascent;
                      it->max_phys_descent = phys_descent;
                    }
+                 else if (wrap_row_used > 0)
+                   {
+                   back_to_wrap:
+                     *it = wrap_it;
+                     it->continuation_lines_width += wrap_x;
+                     row->used[TEXT_AREA] = wrap_row_used;
+                     row->ascent = wrap_row_ascent;
+                     row->height = wrap_row_height;
+                     row->phys_ascent = wrap_row_phys_ascent;
+                     row->phys_height = wrap_row_phys_height;
+                     row->extra_line_spacing = wrap_row_extra_line_spacing;
+                     row->continued_p = 1;
+                     row->ends_at_zv_p = 0;
+                     row->exact_window_width_line_p = 0;
+                     it->continuation_lines_width += x;
+
+                     /* Make sure that a non-default face is extended
+                        up to the right margin of the window.  */
+                     extend_face_to_end_of_line (it);
+                   }
                  else if (it->c == '\t' && FRAME_WINDOW_P (it->f))
                    {
                      /* A TAB that extends past the right edge of the
@@ -16554,7 +16690,7 @@
 
       /* If we truncate lines, we are done when the last displayed
         glyphs reach past the right margin of the window.  */
-      if (it->truncate_lines_p
+      if (it->line_wrap == TRUNCATE
          && (FRAME_WINDOW_P (it->f)
              ? (it->current_x >= it->last_visible_x)
              : (it->current_x > it->last_visible_x)))
@@ -18579,7 +18715,7 @@
        {
          struct glyph *glyph = row->glyphs[TEXT_AREA] + n_glyphs_before + i;
 
-         if (!it->truncate_lines_p
+         if (it->line_wrap != TRUNCATE
              && x + glyph->pixel_width > max_x)
            {
              /* End of continued line or max_x reached.  */
@@ -18635,7 +18771,7 @@
       set_iterator_to_next (it, 1);
 
       /* Stop if truncating at the right edge.  */
-      if (it->truncate_lines_p
+      if (it->line_wrap == TRUNCATE
          && it->current_x >= it->last_visible_x)
        {
          /* Add truncation mark, but don't do it if the line is
@@ -20583,7 +20719,7 @@
   else
     ascent = (height * FONT_BASE (font)) / FONT_HEIGHT (font);
 
-  if (width > 0 && !it->truncate_lines_p
+  if (width > 0 && it->line_wrap != TRUNCATE
       && it->current_x + width > it->last_visible_x)
     width = it->last_visible_x - it->current_x - 1;
 
@@ -24538,11 +24674,18 @@
   DEFVAR_INT ("debug-end-pos", &debug_end_pos, doc: /* Don't ask.  */);
 #endif
 
-  DEFVAR_BOOL ("truncate-partial-width-windows",
-              &truncate_partial_width_windows,
-    doc: /* *Non-nil means truncate lines in all windows less than full frame 
wide.
+  DEFVAR_LISP ("truncate-partial-width-windows",
+              &Vtruncate_partial_width_windows,
+    doc: /* Non-nil means truncate lines in windows with less than the frame 
width.
+For an integer value, truncate lines in each window with less than the
+full frame width, provided the window width is less than that integer;
+otherwise, respect the value of `truncate-lines'.
+
+For any other non-nil value, truncate lines in all windows with
+less than the full frame width.
+
 Nil means to respect the value of `truncate-lines'.  */);
-  truncate_partial_width_windows = 1;
+  Vtruncate_partial_width_windows = make_number (30);
 
   DEFVAR_BOOL ("mode-line-inverse-video", &mode_line_inverse_video,
     doc: /* When nil, display the mode-line/header-line/menu-bar in the 
default face.