1 files changed, 263 insertions, 169 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index b20c4815abc..167b4afadaa 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -843,8 +843,8 @@ static struct text_pos run_window_scroll_functions P_ ((Lisp_Object,
                                                         struct text_pos));
 static void reconsider_clip_changes P_ ((struct window *, struct buffer *));
 static int text_outside_line_unchanged_p P_ ((struct window *, int, int));
-static void store_frame_title_char P_ ((char));
-static int store_frame_title P_ ((const unsigned char *, int, int));
+static void store_mode_line_noprop_char P_ ((char));
+static int store_mode_line_noprop P_ ((const unsigned char *, int, int));
 static void x_consider_frame_title P_ ((Lisp_Object));
 static void handle_stop P_ ((struct it *));
 static int tool_bar_lines_needed P_ ((struct frame *));
@@ -8159,52 +8159,123 @@ echo_area_display (update_frame_p)
 
 
 /***********************************************************************
-                             Frame Titles
+                     Mode Lines and Frame Titles
  ***********************************************************************/
 
+/* A buffer for constructing non-propertized mode-line strings and
+   frame titles in it; allocated from the heap in init_xdisp and
+   resized as needed in store_mode_line_noprop_char.  */
 
-/* The frame title buffering code is also used by Fformat_mode_line.
-   So it is not conditioned by HAVE_WINDOW_SYSTEM.  */
+static char *mode_line_noprop_buf;
 
-/* A buffer for constructing frame titles in it; allocated from the
-   heap in init_xdisp and resized as needed in store_frame_title_char.  */
+/* The buffer's end, and a current output position in it.  */
 
-static char *frame_title_buf;
+static char *mode_line_noprop_buf_end;
+static char *mode_line_noprop_ptr;
 
-/* The buffer's end, and a current output position in it.  */
+static enum {
+  MODE_LINE_DISPLAY = 0,
+  MODE_LINE_TITLE,
+  MODE_LINE_NOPROP,
+  MODE_LINE_STRING
+} mode_line_target;
+
+/* Alist that caches the results of :propertize.
+   Each element is (PROPERTIZED-STRING . PROPERTY-LIST).  */
+static Lisp_Object mode_line_proptrans_alist;
+
+/* List of strings making up the mode-line.  */
+static Lisp_Object mode_line_string_list;
+
+/* Base face property when building propertized mode line string.  */
+static Lisp_Object mode_line_string_face;
+static Lisp_Object mode_line_string_face_prop;
+
+
+/* Unwind data for mode line strings */
+
+static Lisp_Object Vmode_line_unwind_vector;
+
+static Lisp_Object
+format_mode_line_unwind_data (obuf)
+     struct buffer *obuf;
+{
+  int i = 0;
+  Lisp_Object vector;
+
+  /* Reduce consing by keeping one vector in
+     Vwith_echo_area_save_vector.  */
+  vector = Vmode_line_unwind_vector;
+  Vmode_line_unwind_vector = Qnil;
+
+  if (NILP (vector))
+    vector = Fmake_vector (make_number (7), Qnil);
+
+  AREF (vector, 0) = make_number (mode_line_target);
+  AREF (vector, 1) = make_number (mode_line_noprop_ptr - mode_line_noprop_buf);
+  AREF (vector, 2) = mode_line_string_list;
+  AREF (vector, 3) = mode_line_proptrans_alist;
+  AREF (vector, 4) = mode_line_string_face;
+  AREF (vector, 5) = mode_line_string_face_prop;
+
+  if (obuf)
+    XSETBUFFER (AREF (vector, 6), obuf);
+  else
+    AREF (vector, 6) = Qnil;
+
+  return vector;
+}
+
+static Lisp_Object
+unwind_format_mode_line (vector)
+     Lisp_Object vector;
+{
+  mode_line_target = XINT (AREF (vector, 0));
+  mode_line_noprop_ptr = mode_line_noprop_buf + XINT (AREF (vector, 1));
+  mode_line_string_list = AREF (vector, 2);
+  mode_line_proptrans_alist = AREF (vector, 3);
+  mode_line_string_face = AREF (vector, 4);
+  mode_line_string_face_prop = AREF (vector, 5);
 
-static char *frame_title_buf_end;
-static char *frame_title_ptr;
+  if (!NILP (AREF (vector, 6)))
+    {
+      set_buffer_internal_1 (XBUFFER (AREF (vector, 6)));
+      AREF (vector, 6) = Qnil;
+    }
 
+  Vmode_line_unwind_vector = vector;
+  return Qnil;
+}
 
-/* Store a single character C for the frame title in frame_title_buf.
-   Re-allocate frame_title_buf if necessary.  */
+
+/* Store a single character C for the frame title in mode_line_noprop_buf.
+   Re-allocate mode_line_noprop_buf if necessary.  */
 
 static void
 #ifdef PROTOTYPES
-store_frame_title_char (char c)
+store_mode_line_noprop_char (char c)
 #else
-store_frame_title_char (c)
+store_mode_line_noprop_char (c)
     char c;
 #endif
 {
   /* If output position has reached the end of the allocated buffer,
      double the buffer's size.  */
-  if (frame_title_ptr == frame_title_buf_end)
+  if (mode_line_noprop_ptr == mode_line_noprop_buf_end)
     {
-      int len = frame_title_ptr - frame_title_buf;
-      int new_size = 2 * len * sizeof *frame_title_buf;
-      frame_title_buf = (char *) xrealloc (frame_title_buf, new_size);
-      frame_title_buf_end = frame_title_buf + new_size;
-      frame_title_ptr = frame_title_buf + len;
+      int len = mode_line_noprop_ptr - mode_line_noprop_buf;
+      int new_size = 2 * len * sizeof *mode_line_noprop_buf;
+      mode_line_noprop_buf = (char *) xrealloc (mode_line_noprop_buf, new_size);
+      mode_line_noprop_buf_end = mode_line_noprop_buf + new_size;
+      mode_line_noprop_ptr = mode_line_noprop_buf + len;
     }
 
-  *frame_title_ptr++ = c;
+  *mode_line_noprop_ptr++ = c;
 }
 
 
-/* Store part of a frame title in frame_title_buf, beginning at
-   frame_title_ptr.  STR is the string to store.  Do not copy
+/* Store part of a frame title in mode_line_noprop_buf, beginning at
+   mode_line_noprop_ptr.  STR is the string to store.  Do not copy
    characters that yield more columns than PRECISION; PRECISION <= 0
    means copy the whole string.  Pad with spaces until FIELD_WIDTH
    number of characters have been copied; FIELD_WIDTH <= 0 means don't
@@ -8212,7 +8283,7 @@ store_frame_title_char (c)
    frame title.  */
 
 static int
-store_frame_title (str, field_width, precision)
+store_mode_line_noprop (str, field_width, precision)
      const unsigned char *str;
      int field_width, precision;
 {
@@ -8223,19 +8294,23 @@ store_frame_title (str, field_width, precision)
   nbytes = strlen (str);
   n += c_string_width (str, nbytes, precision, &dummy, &nbytes);
   while (nbytes--)
-    store_frame_title_char (*str++);
+    store_mode_line_noprop_char (*str++);
 
   /* Fill up with spaces until FIELD_WIDTH reached.  */
   while (field_width > 0
          && n < field_width)
     {
-      store_frame_title_char (' ');
+      store_mode_line_noprop_char (' ');
       ++n;
     }
 
   return n;
 }
 
+/***********************************************************************
+                             Frame Titles
+ ***********************************************************************/
+
 #ifdef HAVE_WINDOW_SYSTEM
 
 /* Set the title of FRAME, if it has changed.  The title format is
@@ -8255,9 +8330,10 @@ x_consider_frame_title (frame)
       /* Do we have more than one visible frame on this X display?  */
       Lisp_Object tail;
       Lisp_Object fmt;
-      struct buffer *obuf;
+      char *title_start;
       int len;
       struct it it;
+      int count = SPECPDL_INDEX ();
 
       for (tail = Vframe_list; CONSP (tail); tail = XCDR (tail))
         {
@@ -8276,18 +8352,22 @@ x_consider_frame_title (frame)
       multiple_frames = CONSP (tail);
 
       /* Switch to the buffer of selected window of the frame.  Set up
-         frame_title_ptr so that display_mode_element will output into it;
+         mode_line_noprop_ptr so that display_mode_element will output into it;
          then display the title.  */
-      obuf = current_buffer;
+      record_unwind_protect (unwind_format_mode_line,
+                             format_mode_line_unwind_data (current_buffer));
+
       set_buffer_internal_1 (XBUFFER (XWINDOW (f->selected_window)->buffer));
       fmt = FRAME_ICONIFIED_P (f) ? Vicon_title_format : Vframe_title_format;
-      frame_title_ptr = frame_title_buf;
+
+      mode_line_target = MODE_LINE_TITLE;
+      title_start = mode_line_noprop_ptr;
       init_iterator (&it, XWINDOW (f->selected_window), -1, -1,
                      NULL, DEFAULT_FACE_ID);
       display_mode_element (&it, 0, -1, -1, fmt, Qnil, 0);
-      len = frame_title_ptr - frame_title_buf;
-      frame_title_ptr = NULL;
-      set_buffer_internal_1 (obuf);
+      len = mode_line_noprop_ptr - title_start;
+
+      unbind_to (count, Qnil);
 
       /* Set the title only if it's changed.  This avoids consing in
          the common case where it hasn't.  (If it turns out that we've
@@ -8296,8 +8376,8 @@ x_consider_frame_title (frame)
          higher level than this.)  */
       if (! STRINGP (f->name)
           || SBYTES (f->name) != len
-          || bcmp (frame_title_buf, SDATA (f->name), len) != 0)
-        x_implicitly_set_name (f, make_string (frame_title_buf, len), Qnil);
+          || bcmp (title_start, SDATA (f->name), len) != 0)
+        x_implicitly_set_name (f, make_string (title_start, len), Qnil);
     }
 }
 
@@ -15631,18 +15711,6 @@ display_mode_line (w, face_id, format)
   return it.glyph_row->height;
 }
 
-/* Alist that caches the results of :propertize.
-   Each element is (PROPERTIZED-STRING . PROPERTY-LIST).  */
-Lisp_Object mode_line_proptrans_alist;
-
-/* List of strings making up the mode-line.  */
-Lisp_Object mode_line_string_list;
-
-/* Base face property when building propertized mode line string.  */
-static Lisp_Object mode_line_string_face;
-static Lisp_Object mode_line_string_face_prop;
-
-
 /* Contribute ELT to the mode line for window IT->w.  How it
    translates into text depends on its data type.
 
@@ -15663,8 +15731,9 @@ static Lisp_Object mode_line_string_face_prop;
    If RISKY is nonzero, remove (disregard) any properties in any string
    we encounter, and ignore :eval and :propertize.
 
-   If the global variable `frame_title_ptr' is non-NULL, then the output
-   is passed to `store_frame_title' instead of `display_string'.  */
+   The global variable `mode_line_target' determines whether the
+   output is passed to `store_mode_line_noprop',
+   `store_mode_line_string', or `display_string'.  */
 
 static int
 display_mode_element (it, depth, field_width, precision, elt, props, risky)
@@ -15753,21 +15822,27 @@ display_mode_element (it, depth, field_width, precision, elt, props, risky)
         if (literal)
           {
             prec = precision - n;
-            if (frame_title_ptr)
-              n += store_frame_title (SDATA (elt), -1, prec);
-            else if (!NILP (mode_line_string_list))
-              n += store_mode_line_string (NULL, elt, 1, 0, prec, Qnil);
-            else
-              n += display_string (NULL, elt, Qnil, 0, 0, it,
-                                   0, prec, 0, STRING_MULTIBYTE (elt));
+            switch (mode_line_target)
+              {
+              case MODE_LINE_NOPROP:
+              case MODE_LINE_TITLE:
+                n += store_mode_line_noprop (SDATA (elt), -1, prec);
+                break;
+              case MODE_LINE_STRING:
+                n += store_mode_line_string (NULL, elt, 1, 0, prec, Qnil);
+                break;
+              case MODE_LINE_DISPLAY:
+                n += display_string (NULL, elt, Qnil, 0, 0, it,
+                                     0, prec, 0, STRING_MULTIBYTE (elt));
+                break;
+              }
 
             break;
           }
 
         while ((precision <= 0 || n < precision)
                && *this
-               && (frame_title_ptr
-                   || !NILP (mode_line_string_list)
+               && (mode_line_target != MODE_LINE_DISPLAY
                    || it->current_x < it->last_visible_x))
           {
             const unsigned char *last = this;
@@ -15788,29 +15863,36 @@ display_mode_element (it, depth, field_width, precision, elt, props, risky)
                 prec = c_string_width (last, this - last, precision - n,
                                        &nchars, &nbytes);
 
-                if (frame_title_ptr)
-                  n += store_frame_title (last, 0, prec);
-                else if (!NILP (mode_line_string_list))
-                  {
-                    int bytepos = last - lisp_string;
-                    int charpos = string_byte_to_char (elt, bytepos);
-                    int endpos = (precision <= 0
-                                  ? string_byte_to_char (elt,
-                                                         this - lisp_string)
-                                  : charpos + nchars);
-
-                    n += store_mode_line_string (NULL,
-                                                 Fsubstring (elt, make_number (charpos),
-                                                             make_number (endpos)),
-                                                 0, 0, 0, Qnil);
-                  }
-                else
+                switch (mode_line_target)
                   {
-                    int bytepos = last - lisp_string;
-                    int charpos = string_byte_to_char (elt, bytepos);
-                    n += display_string (NULL, elt, Qnil, 0, charpos,
-                                         it, 0, prec, 0,
-                                         STRING_MULTIBYTE (elt));
+                  case MODE_LINE_NOPROP:
+                  case MODE_LINE_TITLE:
+                    n += store_mode_line_noprop (last, 0, prec);
+                    break;
+                  case MODE_LINE_STRING:
+                    {
+                      int bytepos = last - lisp_string;
+                      int charpos = string_byte_to_char (elt, bytepos);
+                      int endpos = (precision <= 0
+                                    ? string_byte_to_char (elt,
+                                                           this - lisp_string)
+                                    : charpos + nchars);
+
+                      n += store_mode_line_string (NULL,
+                                                   Fsubstring (elt, make_number (charpos),
+                                                               make_number (endpos)),
+                                                   0, 0, 0, Qnil);
+                    }
+                    break;
+                  case MODE_LINE_DISPLAY:
+                    {
+                      int bytepos = last - lisp_string;
+                      int charpos = string_byte_to_char (elt, bytepos);
+                      n += display_string (NULL, elt, Qnil, 0, charpos,
+                                           it, 0, prec, 0,
+                                           STRING_MULTIBYTE (elt));
+                    }
+                    break;
                   }
               }
             else /* c == '%' */
@@ -15848,44 +15930,51 @@ display_mode_element (it, depth, field_width, precision, elt, props, risky)
                     spec
                       = decode_mode_spec (it->w, c, field, prec, &multibyte);
 
-                    if (frame_title_ptr)
-                      n += store_frame_title (spec, field, prec);
-                    else if (!NILP (mode_line_string_list))
-                      {
-                        int len = strlen (spec);
-                        Lisp_Object tem = make_string (spec, len);
-                        props = Ftext_properties_at (make_number (charpos), elt);
-                        /* Should only keep face property in props */
-                        n += store_mode_line_string (NULL, tem, 0, field, prec, props);
-                      }
-                    else
+                    switch (mode_line_target)
                       {
-                        int nglyphs_before, nwritten;
-
-                        nglyphs_before = it->glyph_row->used[TEXT_AREA];
-                        nwritten = display_string (spec, Qnil, elt,
-                                                   charpos, 0, it,
-                                                   field, prec, 0,
-                                                   multibyte);
-
-                        /* Assign to the glyphs written above the
-                           string where the `%x' came from, position
-                           of the `%'.  */
-                        if (nwritten > 0)
-                          {
-                            struct glyph *glyph
-                              = (it->glyph_row->glyphs[TEXT_AREA]
-                                 + nglyphs_before);
-                            int i;
-
-                            for (i = 0; i < nwritten; ++i)
-                              {
-                                glyph[i].object = elt;
-                                glyph[i].charpos = charpos;
-                              }
-
-                            n += nwritten;
-                          }
+                      case MODE_LINE_NOPROP:
+                      case MODE_LINE_TITLE:
+                        n += store_mode_line_noprop (spec, field, prec);
+                        break;
+                      case MODE_LINE_STRING:
+                        {
+                          int len = strlen (spec);
+                          Lisp_Object tem = make_string (spec, len);
+                          props = Ftext_properties_at (make_number (charpos), elt);
+                          /* Should only keep face property in props */
+                          n += store_mode_line_string (NULL, tem, 0, field, prec, props);
+                        }
+                        break;
+                      case MODE_LINE_DISPLAY:
+                        {
+                          int nglyphs_before, nwritten;
+
+                          nglyphs_before = it->glyph_row->used[TEXT_AREA];
+                          nwritten = display_string (spec, Qnil, elt,
+                                                     charpos, 0, it,
+                                                     field, prec, 0,
+                                                     multibyte);
+
+                          /* Assign to the glyphs written above the
+                             string where the `%x' came from, position
+                             of the `%'.  */
+                          if (nwritten > 0)
+                            {
+                              struct glyph *glyph
+                                = (it->glyph_row->glyphs[TEXT_AREA]
+                                   + nglyphs_before);
+                              int i;
+
+                              for (i = 0; i < nwritten; ++i)
+                                {
+                                  glyph[i].object = elt;
+                                  glyph[i].charpos = charpos;
+                                }
+
+                              n += nwritten;
+                            }
+                        }
+                        break;
                       }
                   }
                 else /* c == 0 */
@@ -16056,13 +16145,20 @@ display_mode_element (it, depth, field_width, precision, elt, props, risky)
   /* Pad to FIELD_WIDTH.  */
   if (field_width > 0 && n < field_width)
     {
-      if (frame_title_ptr)
-        n += store_frame_title ("", field_width - n, 0);
-      else if (!NILP (mode_line_string_list))
-        n += store_mode_line_string ("", Qnil, 0, field_width - n, 0, Qnil);
-      else
-        n += display_string ("", Qnil, Qnil, 0, 0, it, field_width - n,
-                             0, 0, 0);
+      switch (mode_line_target)
+        {
+        case MODE_LINE_NOPROP:
+        case MODE_LINE_TITLE:
+          n += store_mode_line_noprop ("", field_width - n, 0);
+          break;
+        case MODE_LINE_STRING:
+          n += store_mode_line_string ("", Qnil, 0, field_width - n, 0, Qnil);
+          break;
+        case MODE_LINE_DISPLAY:
+          n += display_string ("", Qnil, Qnil, 0, 0, it, field_width - n,
+                               0, 0, 0);
+          break;
+        }
     }
 
   return n;
@@ -16194,6 +16290,9 @@ are the selected window and the window's buffer).  */)
   struct buffer *old_buffer = NULL;
   int face_id = -1;
   int no_props = INTEGERP (face);
+  int count = SPECPDL_INDEX ();
+  Lisp_Object str;
+  char *string_start = NULL;
 
   if (NILP (window))
     window = selected_window;
@@ -16221,64 +16320,52 @@ are the selected window and the window's buffer).  */)
     face_id = DEFAULT_FACE_ID;
 
   if (XBUFFER (buffer) != current_buffer)
-    {
-      old_buffer = current_buffer;
-      set_buffer_internal_1 (XBUFFER (buffer));
-    }
+    old_buffer = current_buffer;
+
+  record_unwind_protect (unwind_format_mode_line,
+                         format_mode_line_unwind_data (old_buffer));
+
+  if (old_buffer)
+    set_buffer_internal_1 (XBUFFER (buffer));
 
   init_iterator (&it, w, -1, -1, NULL, face_id);
 
-  if (!no_props)
+  if (no_props)
     {
-      mode_line_string_face = face;
-      mode_line_string_face_prop
-        = (NILP (face) ? Qnil : Fcons (Qface, Fcons (face, Qnil)));
-
-      /* We need a dummy last element in mode_line_string_list to
-         indicate we are building the propertized mode-line string.
-         Using mode_line_string_face_prop here GC protects it.  */
-      mode_line_string_list
-        = Fcons (mode_line_string_face_prop, Qnil);
-      frame_title_ptr = NULL;
+      mode_line_target = MODE_LINE_NOPROP;
+      mode_line_string_face_prop = Qnil;
+      mode_line_string_list = Qnil;
+      string_start = mode_line_noprop_ptr;
     }
   else
     {
-      mode_line_string_face_prop = Qnil;
+      mode_line_target = MODE_LINE_STRING;
       mode_line_string_list = Qnil;
-      frame_title_ptr = frame_title_buf;
+      mode_line_string_face = face;
+      mode_line_string_face_prop
+        = (NILP (face) ? Qnil : Fcons (Qface, Fcons (face, Qnil)));
+
+      string_start = NULL;
     }
 
   push_frame_kboard (it.f);
   display_mode_element (&it, 0, 0, 0, format, Qnil, 0);
   pop_frame_kboard ();
 
-  if (old_buffer)
-    set_buffer_internal_1 (old_buffer);
-
-  if (!no_props)
+  if (no_props)
     {
-      Lisp_Object str;
-      mode_line_string_list = Fnreverse (mode_line_string_list);
-      str = Fmapconcat (intern ("identity"), XCDR (mode_line_string_list),
-                        make_string ("", 0));
-      mode_line_string_face_prop = Qnil;
-      mode_line_string_list = Qnil;
-      return str;
+      len = mode_line_noprop_ptr - string_start;
+      str = make_string (string_start, len);
     }
-
-  len = frame_title_ptr - frame_title_buf;
-  if (len > 0 && frame_title_ptr[-1] == '-')
+  else
     {
-      /* Mode lines typically ends with numerous dashes; reduce to two dashes.  */
-      while (frame_title_ptr > frame_title_buf && *--frame_title_ptr == '-')
-        ;
-      frame_title_ptr += 3;  /* restore last non-dash + two dashes */
-      if (len > frame_title_ptr - frame_title_buf)
-        len = frame_title_ptr - frame_title_buf;
+      mode_line_string_list = Fnreverse (mode_line_string_list);
+      str = Fmapconcat (intern ("identity"), mode_line_string_list,
+                        make_string ("", 0));
     }
 
-  frame_title_ptr = NULL;
-  return make_string (frame_title_buf, len);
+  unbind_to (count, Qnil);
+  return str;
 }
 
 /* Write a null-terminated, right justified decimal representation of
@@ -16596,7 +16683,8 @@ decode_mode_spec (w, c, field_width, precision, multibyte)
         register int i;
 
         /* Let lots_of_dashes be a string of infinite length.  */
-        if (!NILP (mode_line_string_list))
+        if (mode_line_target == MODE_LINE_NOPROP ||
+            mode_line_target == MODE_LINE_STRING)
           return "--";
         if (field_width <= 0
             || field_width > sizeof (lots_of_dashes))
@@ -22689,9 +22777,14 @@ syms_of_xdisp ()
 
   mode_line_proptrans_alist = Qnil;
   staticpro (&mode_line_proptrans_alist);
-
   mode_line_string_list = Qnil;
   staticpro (&mode_line_string_list);
+  mode_line_string_face = Qnil;
+  staticpro (&mode_line_string_face);
+  mode_line_string_face_prop = Qnil;
+  staticpro (&mode_line_string_face_prop);
+  Vmode_line_unwind_vector = Qnil;
+  staticpro (&Vmode_line_unwind_vector);
 
   help_echo_string = Qnil;
   staticpro (&help_echo_string);
@@ -23041,9 +23134,10 @@ init_xdisp ()
     /* Allocate the buffer for frame titles.
        Also used for `format-mode-line'.  */
     int size = 100;
-    frame_title_buf = (char *) xmalloc (size);
-    frame_title_buf_end = frame_title_buf + size;
-    frame_title_ptr = NULL;
+    mode_line_noprop_buf = (char *) xmalloc (size);
+    mode_line_noprop_buf_end = mode_line_noprop_buf + size;
+    mode_line_noprop_ptr = mode_line_noprop_buf;
+    mode_line_target = MODE_LINE_DISPLAY;
   }
 
   help_echo_showing_p = 0;