X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/0273a428450950cf846767982cdb77cc9937a1f3..d3155315c85212f224fc5df0239182dafdfd6284:/src/undo.c

diff --git a/src/undo.c b/src/undo.c
index 63edc8e9b8..750bc8afff 100644
--- a/src/undo.c
+++ b/src/undo.c
@@ -1,5 +1,5 @@
 /* undo handling for GNU Emacs.
-   Copyright (C) 1990, 1993-1994, 2000-2013 Free Software Foundation,
+   Copyright (C) 1990, 1993-1994, 2000-2015 Free Software Foundation,
    Inc.
 
 This file is part of GNU Emacs.
@@ -34,12 +34,6 @@ static struct buffer *last_undo_buffer;
 static struct buffer *last_boundary_buffer;
 static ptrdiff_t last_boundary_position;
 
-Lisp_Object Qinhibit_read_only;
-
-/* Marker for function call undo list elements.  */
-
-Lisp_Object Qapply;
-
 /* The first time a command records something for undo.
    it also allocates the undo-boundary object
    which will be added to the list at the end of the command.
@@ -55,7 +49,7 @@ static Lisp_Object pending_boundary;
 static void
 record_point (ptrdiff_t pt)
 {
-  int at_boundary;
+  bool at_boundary;
 
   /* Don't record position of pt when undo_inhibit_record_point holds.  */
   if (undo_inhibit_record_point)
@@ -75,27 +69,8 @@ record_point (ptrdiff_t pt)
     Fundo_boundary ();
   last_undo_buffer = current_buffer;
 
-  if (CONSP (BVAR (current_buffer, undo_list)))
-    {
-      /* Set AT_BOUNDARY to 1 only when we have nothing other than
-         marker adjustment before undo boundary.  */
-
-      Lisp_Object tail = BVAR (current_buffer, undo_list), elt;
-
-      while (1)
-	{
-	  if (NILP (tail))
-	    elt = Qnil;
-	  else
-	    elt = XCAR (tail);
-	  if (NILP (elt) || ! (CONSP (elt) && MARKERP (XCAR (elt))))
-	    break;
-	  tail = XCDR (tail);
-	}
-      at_boundary = NILP (elt);
-    }
-  else
-    at_boundary = 1;
+  at_boundary = ! CONSP (BVAR (current_buffer, undo_list))
+                || NILP (XCAR (BVAR (current_buffer, undo_list)));
 
   if (MODIFF <= SAVE_MODIFF)
     record_first_change ();
@@ -147,11 +122,61 @@ record_insert (ptrdiff_t beg, ptrdiff_t length)
 		  Fcons (Fcons (lbeg, lend), BVAR (current_buffer, undo_list)));
 }
 
-/* Record that a deletion is about to take place,
-   of the characters in STRING, at location BEG.  */
+/* Record the fact that markers in the region of FROM, TO are about to
+   be adjusted.  This is done only when a marker points within text
+   being deleted, because that's the only case where an automatic
+   marker adjustment won't be inverted automatically by undoing the
+   buffer modification.  */
+
+static void
+record_marker_adjustments (ptrdiff_t from, ptrdiff_t to)
+{
+  Lisp_Object marker;
+  register struct Lisp_Marker *m;
+  register ptrdiff_t charpos, adjustment;
+
+  /* Allocate a cons cell to be the undo boundary after this command.  */
+  if (NILP (pending_boundary))
+    pending_boundary = Fcons (Qnil, Qnil);
+
+  if (current_buffer != last_undo_buffer)
+    Fundo_boundary ();
+  last_undo_buffer = current_buffer;
+
+  for (m = BUF_MARKERS (current_buffer); m; m = m->next)
+    {
+      charpos = m->charpos;
+      eassert (charpos <= Z);
+
+      if (from <= charpos && charpos <= to)
+        {
+          /* insertion_type nil markers will end up at the beginning of
+             the re-inserted text after undoing a deletion, and must be
+             adjusted to move them to the correct place.
+
+             insertion_type t markers will automatically move forward
+             upon re-inserting the deleted text, so we have to arrange
+             for them to move backward to the correct position.  */
+          adjustment = (m->insertion_type ? to : from) - charpos;
+
+          if (adjustment)
+            {
+              XSETMISC (marker, m);
+              bset_undo_list
+                (current_buffer,
+                 Fcons (Fcons (marker, make_number (adjustment)),
+                        BVAR (current_buffer, undo_list)));
+            }
+        }
+    }
+}
+
+/* Record that a deletion is about to take place, of the characters in
+   STRING, at location BEG.  Optionally record adjustments for markers
+   in the region STRING occupies in the current buffer.  */
 
 void
-record_delete (ptrdiff_t beg, Lisp_Object string)
+record_delete (ptrdiff_t beg, Lisp_Object string, bool record_markers)
 {
   Lisp_Object sbeg;
 
@@ -169,34 +194,15 @@ record_delete (ptrdiff_t beg, Lisp_Object string)
       record_point (beg);
     }
 
-  bset_undo_list
-    (current_buffer,
-     Fcons (Fcons (string, sbeg), BVAR (current_buffer, undo_list)));
-}
-
-/* Record the fact that MARKER is about to be adjusted by ADJUSTMENT.
-   This is done only when a marker points within text being deleted,
-   because that's the only case where an automatic marker adjustment
-   won't be inverted automatically by undoing the buffer modification.  */
-
-void
-record_marker_adjustment (Lisp_Object marker, ptrdiff_t adjustment)
-{
-  if (EQ (BVAR (current_buffer, undo_list), Qt))
-    return;
-
-  /* Allocate a cons cell to be the undo boundary after this command.  */
-  if (NILP (pending_boundary))
-    pending_boundary = Fcons (Qnil, Qnil);
-
-  if (current_buffer != last_undo_buffer)
-    Fundo_boundary ();
-  last_undo_buffer = current_buffer;
+  /* primitive-undo assumes marker adjustments are recorded
+     immediately before the deletion is recorded.  See bug 16818
+     discussion.  */
+  if (record_markers)
+    record_marker_adjustments (beg, beg + SCHARS (string));
 
   bset_undo_list
     (current_buffer,
-     Fcons (Fcons (marker, make_number (adjustment)),
-	    BVAR (current_buffer, undo_list)));
+     Fcons (Fcons (string, sbeg), BVAR (current_buffer, undo_list)));
 }
 
 /* Record that a replacement is about to take place,
@@ -206,7 +212,7 @@ record_marker_adjustment (Lisp_Object marker, ptrdiff_t adjustment)
 void
 record_change (ptrdiff_t beg, ptrdiff_t length)
 {
-  record_delete (beg, make_buffer_string (beg, beg + length, 1));
+  record_delete (beg, make_buffer_string (beg, beg + length, true), false);
   record_insert (beg, length);
 }
 
@@ -229,10 +235,9 @@ record_first_change (void)
   if (base_buffer->base_buffer)
     base_buffer = base_buffer->base_buffer;
 
-  bset_undo_list
-    (current_buffer,
-     Fcons (Fcons (Qt, make_lisp_time (base_buffer->modtime)),
-	    BVAR (current_buffer, undo_list)));
+  bset_undo_list (current_buffer,
+		  Fcons (Fcons (Qt, Fvisited_file_modtime ()),
+			 BVAR (current_buffer, undo_list)));
 }
 
 /* Record a change in property PROP (whose old value was VAL)
@@ -245,7 +250,7 @@ record_property_change (ptrdiff_t beg, ptrdiff_t length,
 {
   Lisp_Object lbeg, lend, entry;
   struct buffer *obuf = current_buffer, *buf = XBUFFER (buffer);
-  int boundary = 0;
+  bool boundary = false;
 
   if (EQ (BVAR (buf, undo_list), Qt))
     return;
@@ -255,7 +260,7 @@ record_property_change (ptrdiff_t beg, ptrdiff_t length,
     pending_boundary = Fcons (Qnil, Qnil);
 
   if (buf != last_undo_buffer)
-    boundary = 1;
+    boundary = true;
   last_undo_buffer = buf;
 
   /* Switch temporarily to the buffer that was changed.  */
@@ -445,17 +450,13 @@ truncate_undo_list (struct buffer *b)
   unbind_to (count, Qnil);
 }
 
-static _Noreturn void
-user_error (const char *msg)
-{
-  xsignal1 (Quser_error, build_string (msg));
-}
-
 
 void
 syms_of_undo (void)
 {
   DEFSYM (Qinhibit_read_only, "inhibit-read-only");
+
+  /* Marker for function call undo list elements.  */
   DEFSYM (Qapply, "apply");
 
   pending_boundary = Qnil;
@@ -518,5 +519,5 @@ so it must make sure not to do a lot of consing.  */);
 
   DEFVAR_BOOL ("undo-inhibit-record-point", undo_inhibit_record_point,
 	       doc: /* Non-nil means do not record `point' in `buffer-undo-list'.  */);
-  undo_inhibit_record_point = 0;
+  undo_inhibit_record_point = false;
 }