1 files changed, 558 insertions, 296 deletions

diff --git a/src/buffer.h b/src/buffer.h
index fa65a4b81fd..fbbbf1b8434 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -1,6 +1,6 @@
 /* Header file for the buffer manipulation primitives.
 
-Copyright (C) 1985-1986, 1993-1995, 1997-2011
+Copyright (C) 1985-1986, 1993-1995, 1997-2012
                  Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
@@ -19,6 +19,12 @@ You should have received a copy of the GNU General Public License
 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include <sys/types.h> /* for off_t, time_t */
+#include "systime.h" /* for EMACS_TIME */
+
+INLINE_HEADER_BEGIN
+#ifndef BUFFER_INLINE
+# define BUFFER_INLINE INLINE
+#endif
 
 /* Accessing the parameters of the current buffer.  */
 
@@ -187,9 +193,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 /* FIXME: should we move this into ->text->auto_save_modiff?  */
 #define BUF_AUTOSAVE_MODIFF(buf) ((buf)->auto_save_modified)
 
-/* Interval tree of buffer.  */
-#define BUF_INTERVALS(buf) ((buf)->text->intervals)
-
 /* Marker chain of buffer.  */
 #define BUF_MARKERS(buf) ((buf)->text->markers)
 
@@ -245,12 +248,12 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #define BUF_TEMP_SET_PT(buffer, position) \
   (temp_set_point ((buffer), (position)))
 
-extern void set_point (EMACS_INT);
-extern void temp_set_point (struct buffer *, EMACS_INT);
-extern void set_point_both (EMACS_INT, EMACS_INT);
+extern void set_point (ptrdiff_t);
+extern void temp_set_point (struct buffer *, ptrdiff_t);
+extern void set_point_both (ptrdiff_t, ptrdiff_t);
 extern void temp_set_point_both (struct buffer *,
-                                 EMACS_INT, EMACS_INT);
-extern void enlarge_buffer_text (struct buffer *, EMACS_INT);
+                                 ptrdiff_t, ptrdiff_t);
+extern void enlarge_buffer_text (struct buffer *, ptrdiff_t);
 
 
 /* Macros for setting the BEGV, ZV or PT of a given buffer.
@@ -343,7 +346,8 @@ while (0)
  - (ptr - (current_buffer)->text->beg <= GPT_BYTE - BEG_BYTE ? 0 : GAP_SIZE) \
  + BEG_BYTE)
 
-/* Return character at byte position POS.  */
+/* Return character at byte position POS.  See the caveat WARNING for
+   FETCH_MULTIBYTE_CHAR below.  */
 
 #define FETCH_CHAR(pos)                                 \
   (!NILP (BVAR (current_buffer, enable_multibyte_characters))   \
@@ -354,18 +358,6 @@ while (0)
 
 #define FETCH_BYTE(n) *(BYTE_POS_ADDR ((n)))
 
-/* Variables used locally in FETCH_MULTIBYTE_CHAR.  */
-extern unsigned char *_fetch_multibyte_char_p;
-
-/* Return character code of multi-byte form at byte position POS.  If POS
-   doesn't point the head of valid multi-byte form, only the byte at
-   POS is returned.  No range checking.  */
-
-#define FETCH_MULTIBYTE_CHAR(pos)                                       \
-  (_fetch_multibyte_char_p = (((pos) >= GPT_BYTE ? GAP_SIZE : 0)        \
-                               + (pos) + BEG_ADDR - BEG_BYTE),          \
-   STRING_CHAR (_fetch_multibyte_char_p))
-
 /* Return character at byte position POS.  If the current buffer is unibyte
    and the character is not ASCII, make the returning character
    multibyte.  */
@@ -414,16 +406,6 @@ extern unsigned char *_fetch_multibyte_char_p;
 
 #define BUF_FETCH_BYTE(buf, n) \
   *(BUF_BYTE_ADDRESS ((buf), (n)))
-
-/* Return character code of multi-byte form at byte position POS in BUF.
-   If POS doesn't point the head of valid multi-byte form, only the byte at
-   POS is returned.  No range checking.  */
-
-#define BUF_FETCH_MULTIBYTE_CHAR(buf, pos)                              \
-  (_fetch_multibyte_char_p                                              \
-     = (((pos) >= BUF_GPT_BYTE (buf) ? BUF_GAP_SIZE (buf) : 0)          \
-        + (pos) + BUF_BEG_ADDR (buf) - BEG_BYTE),                       \
-   STRING_CHAR (_fetch_multibyte_char_p))
 
 /* Define the actual buffer data structures.  */
 
@@ -438,38 +420,41 @@ struct buffer_text
        into a buffer's text to functions that malloc.  */
     unsigned char *beg;
 
-    EMACS_INT gpt;              /* Char pos of gap in buffer.  */
-    EMACS_INT z;                /* Char pos of end of buffer.  */
-    EMACS_INT gpt_byte;         /* Byte pos of gap in buffer.  */
-    EMACS_INT z_byte;           /* Byte pos of end of buffer.  */
-    EMACS_INT gap_size;         /* Size of buffer's gap.  */
-    int modiff;                 /* This counts buffer-modification events
+    ptrdiff_t gpt;              /* Char pos of gap in buffer.  */
+    ptrdiff_t z;                /* Char pos of end of buffer.  */
+    ptrdiff_t gpt_byte;         /* Byte pos of gap in buffer.  */
+    ptrdiff_t z_byte;           /* Byte pos of end of buffer.  */
+    ptrdiff_t gap_size;         /* Size of buffer's gap.  */
+    EMACS_INT modiff;           /* This counts buffer-modification events
                                    for this buffer.  It is incremented for
                                    each such event, and never otherwise
                                    changed.  */
-    int chars_modiff;           /* This is modified with character change
+    EMACS_INT chars_modiff;     /* This is modified with character change
                                    events for this buffer.  It is set to
                                    modiff for each such event, and never
                                    otherwise changed.  */
-    int save_modiff;            /* Previous value of modiff, as of last
+    EMACS_INT save_modiff;      /* Previous value of modiff, as of last
                                    time buffer visited or saved a file.  */
 
-    int overlay_modiff;         /* Counts modifications to overlays.  */
+    EMACS_INT overlay_modiff;   /* Counts modifications to overlays.  */
+
+    EMACS_INT compact;          /* Set to modiff each time when compact_buffer
+                                   is called for this buffer.  */
 
     /* Minimum value of GPT - BEG since last redisplay that finished.  */
-    EMACS_INT beg_unchanged;
+    ptrdiff_t beg_unchanged;
 
     /* Minimum value of Z - GPT since last redisplay that finished.  */
-    EMACS_INT end_unchanged;
+    ptrdiff_t end_unchanged;
 
     /* MODIFF as of last redisplay that finished; if it matches MODIFF,
        beg_unchanged and end_unchanged contain no useful information.  */
-    int unchanged_modified;
+    EMACS_INT unchanged_modified;
 
     /* BUF_OVERLAY_MODIFF of current buffer, as of last redisplay that
        finished; if it matches BUF_OVERLAY_MODIFF, beg_unchanged and
        end_unchanged contain no useful information.  */
-    int overlay_unchanged_modified;
+    EMACS_INT overlay_unchanged_modified;
 
     /* Properties of this buffer's text.  */
     INTERVAL intervals;
@@ -486,267 +471,164 @@ struct buffer_text
     /* Usually 0.  Temporarily set to 1 in decode_coding_gap to
        prevent Fgarbage_collect from shrinking the gap and losing
        not-yet-decoded bytes.  */
-    int inhibit_shrinking;
+    bool inhibit_shrinking;
   };
 
-/* Lisp fields in struct buffer are hidden from most code and accessed
-   via the BVAR macro, below.  Only select pieces of code, like the GC,
-   are allowed to use BUFFER_INTERNAL_FIELD.  */
-#define BUFFER_INTERNAL_FIELD(field) field ## _
+/* Most code should use this macro to access Lisp fields in struct buffer.  */
 
-/* Most code should use this macro to access Lisp fields in struct
-   buffer.  */
-#define BVAR(buf, field) ((buf)->BUFFER_INTERNAL_FIELD (field))
+#define BVAR(buf, field) ((buf)->INTERNAL_FIELD (field))
 
 /* This is the structure that the buffer Lisp object points to.  */
 
 struct buffer
 {
-  /* Everything before the `name' slot must be of a non-Lisp_Object type,
-     and every slot after `name' must be a Lisp_Object.
-
-     Check out mark_buffer (alloc.c) to see why.  */
-
-  /* HEADER.NEXT is the next buffer, in chain of all buffers,
-     including killed buffers.
-     This chain is used only for garbage collection, in order to
-     collect killed buffers properly.
-     Note that vectors and most pseudovectors are all on one chain,
-     but buffers are on a separate chain of their own.  */
   struct vectorlike_header header;
 
-  /* This structure holds the coordinates of the buffer contents
-     in ordinary buffers.  In indirect buffers, this is not used.  */
-  struct buffer_text own_text;
-
-  /* This points to the `struct buffer_text' that used for this buffer.
-     In an ordinary buffer, this is the own_text field above.
-     In an indirect buffer, this is the own_text field of another buffer.  */
-  struct buffer_text *text;
-
-  /* Char position of point in buffer.  */
-  EMACS_INT pt;
-  /* Byte position of point in buffer.  */
-  EMACS_INT pt_byte;
-  /* Char position of beginning of accessible range.  */
-  EMACS_INT begv;
-  /* Byte position of beginning of accessible range.  */
-  EMACS_INT begv_byte;
-  /* Char position of end of accessible range.  */
-  EMACS_INT zv;
-  /* Byte position of end of accessible range.  */
-  EMACS_INT zv_byte;
-
-  /* In an indirect buffer, this points to the base buffer.
-     In an ordinary buffer, it is 0.  */
-  struct buffer *base_buffer;
-
-  /* A non-zero value in slot IDX means that per-buffer variable
-     with index IDX has a local value in this buffer.  The index IDX
-     for a buffer-local variable is stored in that variable's slot
-     in buffer_local_flags as a Lisp integer.  If the index is -1,
-     this means the variable is always local in all buffers.  */
-#define MAX_PER_BUFFER_VARS 50
-  char local_flags[MAX_PER_BUFFER_VARS];
-
-  /* Set to the modtime of the visited file when read or written.
-     -1 means visited file was nonexistent.
-     0 means visited file modtime unknown; in no case complain
-     about any mismatch on next save attempt.  */
-  time_t modtime;
-  /* Size of the file when modtime was set.  This is used to detect the
-     case where the file grew while we were reading it, so the modtime
-     is still the same (since it's rounded up to seconds) but we're actually
-     not up-to-date.  -1 means the size is unknown.  Only meaningful if
-     modtime is actually set.  */
-  off_t modtime_size;
-  /* The value of text->modiff at the last auto-save.  */
-  int auto_save_modified;
-  /* The value of text->modiff at the last display error.
-     Redisplay of this buffer is inhibited until it changes again.  */
-  int display_error_modiff;
-  /* The time at which we detected a failure to auto-save,
-     Or 0 if we didn't have a failure.  */
-  time_t auto_save_failure_time;
-  /* Position in buffer at which display started
-     the last time this buffer was displayed.  */
-  EMACS_INT last_window_start;
-
-  /* Set nonzero whenever the narrowing is changed in this buffer.  */
-  int clip_changed;
-
-  /* If the long line scan cache is enabled (i.e. the buffer-local
-     variable cache-long-line-scans is non-nil), newline_cache
-     points to the newline cache, and width_run_cache points to the
-     width run cache.
-
-     The newline cache records which stretches of the buffer are
-     known *not* to contain newlines, so that they can be skipped
-     quickly when we search for newlines.
-
-     The width run cache records which stretches of the buffer are
-     known to contain characters whose widths are all the same.  If
-     the width run cache maps a character to a value > 0, that value is
-     the character's width; if it maps a character to zero, we don't
-     know what its width is.  This allows compute_motion to process
-     such regions very quickly, using algebra instead of inspecting
-     each character.   See also width_table, below.  */
-  struct region_cache *newline_cache;
-  struct region_cache *width_run_cache;
-
-  /* Non-zero means don't use redisplay optimizations for
-     displaying this buffer.  */
-  unsigned prevent_redisplay_optimizations_p : 1;
-
-  /* List of overlays that end at or before the current center,
-     in order of end-position.  */
-  struct Lisp_Overlay *overlays_before;
+  /* The name of this buffer.  */
+  Lisp_Object INTERNAL_FIELD (name);
 
-  /* List of overlays that end after  the current center,
-     in order of start-position.  */
-  struct Lisp_Overlay *overlays_after;
+  /* The name of the file visited in this buffer, or nil.  */
+  Lisp_Object INTERNAL_FIELD (filename);
 
-  /* Position where the overlay lists are centered.  */
-  EMACS_INT overlay_center;
-
-  /* Everything from here down must be a Lisp_Object.  */
-  /* buffer-local Lisp variables start at `undo_list',
-     tho only the ones from `name' on are GC'd normally.  */
-  #define FIRST_FIELD_PER_BUFFER undo_list
-
-  /* Changes in the buffer are recorded here for undo.
-     t means don't record anything.
-     This information belongs to the base buffer of an indirect buffer,
-     But we can't store it in the  struct buffer_text
-     because local variables have to be right in the  struct buffer.
-     So we copy it around in set_buffer_internal.
-     This comes before `name' because it is marked in a special way.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (undo_list);
+  /* Directory for expanding relative file names.  */
+  Lisp_Object INTERNAL_FIELD (directory);
 
-  /* The name of this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (name);
+  /* True if this buffer has been backed up (if you write to the visited
+     file and it hasn't been backed up, then a backup will be made).  */
+  Lisp_Object INTERNAL_FIELD (backed_up);
 
-  /* The name of the file visited in this buffer, or nil.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (filename);
-  /* Dir for expanding relative file names.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (directory);
-  /* True if this buffer has been backed up (if you write to the
-     visited file and it hasn't been backed up, then a backup will
-     be made).  */
-  /* This isn't really used by the C code, so could be deleted.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (backed_up);
   /* Length of file when last read or saved.
      -1 means auto saving turned off because buffer shrank a lot.
      -2 means don't turn off auto saving if buffer shrinks.
        (That value is used with buffer-swap-text.)
      This is not in the  struct buffer_text
      because it's not used in indirect buffers at all.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (save_length);
+  Lisp_Object INTERNAL_FIELD (save_length);
+
   /* File name used for auto-saving this buffer.
      This is not in the  struct buffer_text
      because it's not used in indirect buffers at all.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (auto_save_file_name);
+  Lisp_Object INTERNAL_FIELD (auto_save_file_name);
 
   /* Non-nil if buffer read-only.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (read_only);
+  Lisp_Object INTERNAL_FIELD (read_only);
+
   /* "The mark".  This is a marker which may
      point into this buffer or may point nowhere.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (mark);
+  Lisp_Object INTERNAL_FIELD (mark);
 
   /* Alist of elements (SYMBOL . VALUE-IN-THIS-BUFFER) for all
      per-buffer variables of this buffer.  For locally unbound
      symbols, just the symbol appears as the element.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (local_var_alist);
+  Lisp_Object INTERNAL_FIELD (local_var_alist);
+
+  /* Symbol naming major mode (e.g., lisp-mode).  */
+  Lisp_Object INTERNAL_FIELD (major_mode);
+
+  /* Pretty name of major mode (e.g., "Lisp"). */
+  Lisp_Object INTERNAL_FIELD (mode_name);
 
-  /* Symbol naming major mode (eg, lisp-mode).  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (major_mode);
-  /* Pretty name of major mode (eg, "Lisp"). */
-  Lisp_Object BUFFER_INTERNAL_FIELD (mode_name);
   /* Mode line element that controls format of mode line.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (mode_line_format);
+  Lisp_Object INTERNAL_FIELD (mode_line_format);
 
   /* Analogous to mode_line_format for the line displayed at the top
      of windows.  Nil means don't display that line.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (header_line_format);
+  Lisp_Object INTERNAL_FIELD (header_line_format);
 
   /* Keys that are bound local to this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (keymap);
+  Lisp_Object INTERNAL_FIELD (keymap);
+
   /* This buffer's local abbrev table.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (abbrev_table);
+  Lisp_Object INTERNAL_FIELD (abbrev_table);
+
   /* This buffer's syntax table.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (syntax_table);
+  Lisp_Object INTERNAL_FIELD (syntax_table);
+
   /* This buffer's category table.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (category_table);
+  Lisp_Object INTERNAL_FIELD (category_table);
 
   /* Values of several buffer-local variables.  */
   /* tab-width is buffer-local so that redisplay can find it
      in buffers that are not current.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (case_fold_search);
-  Lisp_Object BUFFER_INTERNAL_FIELD (tab_width);
-  Lisp_Object BUFFER_INTERNAL_FIELD (fill_column);
-  Lisp_Object BUFFER_INTERNAL_FIELD (left_margin);
+  Lisp_Object INTERNAL_FIELD (case_fold_search);
+  Lisp_Object INTERNAL_FIELD (tab_width);
+  Lisp_Object INTERNAL_FIELD (fill_column);
+  Lisp_Object INTERNAL_FIELD (left_margin);
+
   /* Function to call when insert space past fill column.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (auto_fill_function);
+  Lisp_Object INTERNAL_FIELD (auto_fill_function);
 
   /* Case table for case-conversion in this buffer.
      This char-table maps each char into its lower-case version.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (downcase_table);
+  Lisp_Object INTERNAL_FIELD (downcase_table);
+
   /* Char-table mapping each char to its upper-case version.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (upcase_table);
+  Lisp_Object INTERNAL_FIELD (upcase_table);
+
   /* Char-table for conversion for case-folding search.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (case_canon_table);
+  Lisp_Object INTERNAL_FIELD (case_canon_table);
+
   /* Char-table of equivalences for case-folding search.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (case_eqv_table);
+  Lisp_Object INTERNAL_FIELD (case_eqv_table);
 
   /* Non-nil means do not display continuation lines.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (truncate_lines);
+  Lisp_Object INTERNAL_FIELD (truncate_lines);
+
   /* Non-nil means to use word wrapping when displaying continuation lines.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (word_wrap);
+  Lisp_Object INTERNAL_FIELD (word_wrap);
+
   /* Non-nil means display ctl chars with uparrow.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (ctl_arrow);
+  Lisp_Object INTERNAL_FIELD (ctl_arrow);
+
   /* Non-nil means reorder bidirectional text for display in the
      visual order.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (bidi_display_reordering);
+  Lisp_Object INTERNAL_FIELD (bidi_display_reordering);
+
   /* If non-nil, specifies which direction of text to force in all the
      paragraphs of the buffer.  Nil means determine paragraph
      direction dynamically for each paragraph.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (bidi_paragraph_direction);
+  Lisp_Object INTERNAL_FIELD (bidi_paragraph_direction);
+
   /* Non-nil means do selective display;
      see doc string in syms_of_buffer (buffer.c) for details.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (selective_display);
-#ifndef old
+  Lisp_Object INTERNAL_FIELD (selective_display);
+
   /* Non-nil means show ... at end of line followed by invisible lines.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (selective_display_ellipses);
-#endif
+  Lisp_Object INTERNAL_FIELD (selective_display_ellipses);
+
   /* Alist of (FUNCTION . STRING) for each minor mode enabled in buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (minor_modes);
+  Lisp_Object INTERNAL_FIELD (minor_modes);
+
   /* t if "self-insertion" should overwrite; `binary' if it should also
      overwrite newlines and tabs - for editing executables and the like.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (overwrite_mode);
-  /* non-nil means abbrev mode is on.  Expand abbrevs automatically.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (abbrev_mode);
+  Lisp_Object INTERNAL_FIELD (overwrite_mode);
+
+  /* Non-nil means abbrev mode is on.  Expand abbrevs automatically.  */
+  Lisp_Object INTERNAL_FIELD (abbrev_mode);
+
   /* Display table to use for text in this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (display_table);
+  Lisp_Object INTERNAL_FIELD (display_table);
+
   /* t means the mark and region are currently active.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (mark_active);
+  Lisp_Object INTERNAL_FIELD (mark_active);
 
   /* Non-nil means the buffer contents are regarded as multi-byte
      form of characters, not a binary code.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (enable_multibyte_characters);
+  Lisp_Object INTERNAL_FIELD (enable_multibyte_characters);
 
   /* Coding system to be used for encoding the buffer contents on
      saving.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (buffer_file_coding_system);
+  Lisp_Object INTERNAL_FIELD (buffer_file_coding_system);
 
   /* List of symbols naming the file format used for visited file.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (file_format);
+  Lisp_Object INTERNAL_FIELD (file_format);
 
   /* List of symbols naming the file format used for auto-save file.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (auto_save_file_format);
+  Lisp_Object INTERNAL_FIELD (auto_save_file_format);
 
   /* True if the newline position cache and width run cache are
      enabled.  See search.c and indent.c.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (cache_long_line_scans);
+  Lisp_Object INTERNAL_FIELD (cache_long_line_scans);
 
   /* If the width run cache is enabled, this table contains the
      character widths width_run_cache (see above) assumes.  When we
@@ -754,105 +636,377 @@ struct buffer
      current display table to see whether the display table has
      affected the widths of any characters.  If it has, we
      invalidate the width run cache, and re-initialize width_table.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (width_table);
+  Lisp_Object INTERNAL_FIELD (width_table);
 
   /* In an indirect buffer, or a buffer that is the base of an
      indirect buffer, this holds a marker that records
      PT for this buffer when the buffer is not current.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (pt_marker);
+  Lisp_Object INTERNAL_FIELD (pt_marker);
 
   /* In an indirect buffer, or a buffer that is the base of an
      indirect buffer, this holds a marker that records
      BEGV for this buffer when the buffer is not current.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (begv_marker);
+  Lisp_Object INTERNAL_FIELD (begv_marker);
 
   /* In an indirect buffer, or a buffer that is the base of an
      indirect buffer, this holds a marker that records
      ZV for this buffer when the buffer is not current.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (zv_marker);
+  Lisp_Object INTERNAL_FIELD (zv_marker);
 
   /* This holds the point value before the last scroll operation.
      Explicitly setting point sets this to nil.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (point_before_scroll);
+  Lisp_Object INTERNAL_FIELD (point_before_scroll);
 
   /* Truename of the visited file, or nil.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (file_truename);
+  Lisp_Object INTERNAL_FIELD (file_truename);
 
   /* Invisibility spec of this buffer.
      t => any non-nil `invisible' property means invisible.
      A list => `invisible' property means invisible
      if it is memq in that list.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (invisibility_spec);
+  Lisp_Object INTERNAL_FIELD (invisibility_spec);
 
   /* This is the last window that was selected with this buffer in it,
      or nil if that window no longer displays this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (last_selected_window);
+  Lisp_Object INTERNAL_FIELD (last_selected_window);
 
   /* Incremented each time the buffer is displayed in a window.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (display_count);
+  Lisp_Object INTERNAL_FIELD (display_count);
 
   /* Widths of left and right marginal areas for windows displaying
      this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (left_margin_cols), BUFFER_INTERNAL_FIELD (right_margin_cols);
+  Lisp_Object INTERNAL_FIELD (left_margin_cols);
+  Lisp_Object INTERNAL_FIELD (right_margin_cols);
 
   /* Widths of left and right fringe areas for windows displaying
      this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (left_fringe_width), BUFFER_INTERNAL_FIELD (right_fringe_width);
+  Lisp_Object INTERNAL_FIELD (left_fringe_width);
+  Lisp_Object INTERNAL_FIELD (right_fringe_width);
 
   /* Non-nil means fringes are drawn outside display margins;
      othersize draw them between margin areas and text.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (fringes_outside_margins);
+  Lisp_Object INTERNAL_FIELD (fringes_outside_margins);
 
   /* Width and type of scroll bar areas for windows displaying
      this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (scroll_bar_width), BUFFER_INTERNAL_FIELD (vertical_scroll_bar_type);
+  Lisp_Object INTERNAL_FIELD (scroll_bar_width);
+  Lisp_Object INTERNAL_FIELD (vertical_scroll_bar_type);
 
   /* Non-nil means indicate lines not displaying text (in a style
      like vi).  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (indicate_empty_lines);
+  Lisp_Object INTERNAL_FIELD (indicate_empty_lines);
 
   /* Non-nil means indicate buffer boundaries and scrolling.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (indicate_buffer_boundaries);
+  Lisp_Object INTERNAL_FIELD (indicate_buffer_boundaries);
 
   /* Logical to physical fringe bitmap mappings.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (fringe_indicator_alist);
+  Lisp_Object INTERNAL_FIELD (fringe_indicator_alist);
 
   /* Logical to physical cursor bitmap mappings.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (fringe_cursor_alist);
+  Lisp_Object INTERNAL_FIELD (fringe_cursor_alist);
 
   /* Time stamp updated each time this buffer is displayed in a window.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (display_time);
+  Lisp_Object INTERNAL_FIELD (display_time);
 
   /* If scrolling the display because point is below the bottom of a
      window showing this buffer, try to choose a window start so
      that point ends up this number of lines from the top of the
      window.  Nil means that scrolling method isn't used.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (scroll_up_aggressively);
+  Lisp_Object INTERNAL_FIELD (scroll_up_aggressively);
 
   /* If scrolling the display because point is above the top of a
      window showing this buffer, try to choose a window start so
      that point ends up this number of lines from the bottom of the
      window.  Nil means that scrolling method isn't used.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (scroll_down_aggressively);
+  Lisp_Object INTERNAL_FIELD (scroll_down_aggressively);
 
   /* Desired cursor type in this buffer.  See the doc string of
      per-buffer variable `cursor-type'.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (cursor_type);
+  Lisp_Object INTERNAL_FIELD (cursor_type);
 
   /* An integer > 0 means put that number of pixels below text lines
      in the display of this buffer.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (extra_line_spacing);
+  Lisp_Object INTERNAL_FIELD (extra_line_spacing);
 
-  /* *Cursor type to display in non-selected windows.
+  /* Cursor type to display in non-selected windows.
      t means to use hollow box cursor.
      See `cursor-type' for other values.  */
-  Lisp_Object BUFFER_INTERNAL_FIELD (cursor_in_non_selected_windows);
+  Lisp_Object INTERNAL_FIELD (cursor_in_non_selected_windows);
+
+  /* No more Lisp_Object beyond this point.  Except undo_list,
+     which is handled specially in Fgarbage_collect .  */
+
+  /* This structure holds the coordinates of the buffer contents
+     in ordinary buffers.  In indirect buffers, this is not used.  */
+  struct buffer_text own_text;
+
+  /* This points to the `struct buffer_text' that used for this buffer.
+     In an ordinary buffer, this is the own_text field above.
+     In an indirect buffer, this is the own_text field of another buffer.  */
+  struct buffer_text *text;
+
+  /* Next buffer, in chain of all buffers, including killed ones.  */
+  struct buffer *next;
+
+  /* Char position of point in buffer.  */
+  ptrdiff_t pt;
+
+  /* Byte position of point in buffer.  */
+  ptrdiff_t pt_byte;
+
+  /* Char position of beginning of accessible range.  */
+  ptrdiff_t begv;
+
+  /* Byte position of beginning of accessible range.  */
+  ptrdiff_t begv_byte;
+
+  /* Char position of end of accessible range.  */
+  ptrdiff_t zv;
+
+  /* Byte position of end of accessible range.  */
+  ptrdiff_t zv_byte;
+
+  /* In an indirect buffer, this points to the base buffer.
+     In an ordinary buffer, it is 0.  */
+  struct buffer *base_buffer;
+
+  /* In an indirect buffer, this is -1. In an ordinary buffer,
+     it's the number of indirect buffers that share our text;
+     zero means that we're the only owner of this text.  */
+  int indirections;
+
+  /* A non-zero value in slot IDX means that per-buffer variable
+     with index IDX has a local value in this buffer.  The index IDX
+     for a buffer-local variable is stored in that variable's slot
+     in buffer_local_flags as a Lisp integer.  If the index is -1,
+     this means the variable is always local in all buffers.  */
+#define MAX_PER_BUFFER_VARS 50
+  char local_flags[MAX_PER_BUFFER_VARS];
+
+  /* Set to the modtime of the visited file when read or written.
+     EMACS_NSECS (modtime) == NONEXISTENT_MODTIME_NSECS means
+     visited file was nonexistent.  EMACS_NSECS (modtime) ==
+     UNKNOWN_MODTIME_NSECS means visited file modtime unknown;
+     in no case complain about any mismatch on next save attempt.  */
+#define NONEXISTENT_MODTIME_NSECS (-1)
+#define UNKNOWN_MODTIME_NSECS (-2)
+  EMACS_TIME modtime;
+
+  /* Size of the file when modtime was set.  This is used to detect the
+     case where the file grew while we were reading it, so the modtime
+     is still the same (since it's rounded up to seconds) but we're actually
+     not up-to-date.  -1 means the size is unknown.  Only meaningful if
+     modtime is actually set.  */
+  off_t modtime_size;
+
+  /* The value of text->modiff at the last auto-save.  */
+  EMACS_INT auto_save_modified;
+
+  /* The value of text->modiff at the last display error.
+     Redisplay of this buffer is inhibited until it changes again.  */
+  EMACS_INT display_error_modiff;
+
+  /* The time at which we detected a failure to auto-save,
+     Or 0 if we didn't have a failure.  */
+  time_t auto_save_failure_time;
+
+  /* Position in buffer at which display started
+     the last time this buffer was displayed.  */
+  ptrdiff_t last_window_start;
+
+  /* If the long line scan cache is enabled (i.e. the buffer-local
+     variable cache-long-line-scans is non-nil), newline_cache
+     points to the newline cache, and width_run_cache points to the
+     width run cache.
+
+     The newline cache records which stretches of the buffer are
+     known *not* to contain newlines, so that they can be skipped
+     quickly when we search for newlines.
+
+     The width run cache records which stretches of the buffer are
+     known to contain characters whose widths are all the same.  If
+     the width run cache maps a character to a value > 0, that value is
+     the character's width; if it maps a character to zero, we don't
+     know what its width is.  This allows compute_motion to process
+     such regions very quickly, using algebra instead of inspecting
+     each character.   See also width_table, below.  */
+  struct region_cache *newline_cache;
+  struct region_cache *width_run_cache;
+
+  /* Non-zero means don't use redisplay optimizations for
+     displaying this buffer.  */
+  unsigned prevent_redisplay_optimizations_p : 1;
+
+  /* Non-zero whenever the narrowing is changed in this buffer.  */
+  unsigned clip_changed : 1;
+
+  /* List of overlays that end at or before the current center,
+     in order of end-position.  */
+  struct Lisp_Overlay *overlays_before;
+
+  /* List of overlays that end after  the current center,
+     in order of start-position.  */
+  struct Lisp_Overlay *overlays_after;
 
-  /* This must be the last field in the above list.  */
-  #define LAST_FIELD_PER_BUFFER cursor_in_non_selected_windows
+  /* Position where the overlay lists are centered.  */
+  ptrdiff_t overlay_center;
+
+  /* Changes in the buffer are recorded here for undo, and t means
+     don't record anything.  This information belongs to the base
+     buffer of an indirect buffer.  But we can't store it in the
+     struct buffer_text because local variables have to be right in
+     the struct buffer. So we copy it around in set_buffer_internal.  */
+  Lisp_Object INTERNAL_FIELD (undo_list);
 };
 
-
+/* Most code should use these functions to set Lisp fields in struct
+   buffer.  */
+BUFFER_INLINE void
+bset_bidi_paragraph_direction (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (bidi_paragraph_direction) = val;
+}
+BUFFER_INLINE void
+bset_case_canon_table (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (case_canon_table) = val;
+}
+BUFFER_INLINE void
+bset_case_eqv_table (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (case_eqv_table) = val;
+}
+BUFFER_INLINE void
+bset_directory (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (directory) = val;
+}
+BUFFER_INLINE void
+bset_display_count (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (display_count) = val;
+}
+BUFFER_INLINE void
+bset_display_time (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (display_time) = val;
+}
+BUFFER_INLINE void
+bset_downcase_table (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (downcase_table) = val;
+}
+BUFFER_INLINE void
+bset_enable_multibyte_characters (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (enable_multibyte_characters) = val;
+}
+BUFFER_INLINE void
+bset_filename (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (filename) = val;
+}
+BUFFER_INLINE void
+bset_keymap (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (keymap) = val;
+}
+BUFFER_INLINE void
+bset_last_selected_window (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (last_selected_window) = val;
+}
+BUFFER_INLINE void
+bset_local_var_alist (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (local_var_alist) = val;
+}
+BUFFER_INLINE void
+bset_mark_active (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (mark_active) = val;
+}
+BUFFER_INLINE void
+bset_point_before_scroll (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (point_before_scroll) = val;
+}
+BUFFER_INLINE void
+bset_read_only (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (read_only) = val;
+}
+BUFFER_INLINE void
+bset_truncate_lines (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (truncate_lines) = val;
+}
+BUFFER_INLINE void
+bset_undo_list (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (undo_list) = val;
+}
+BUFFER_INLINE void
+bset_upcase_table (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (upcase_table) = val;
+}
+BUFFER_INLINE void
+bset_width_table (struct buffer *b, Lisp_Object val)
+{
+  b->INTERNAL_FIELD (width_table) = val;
+}
+
+/* Number of Lisp_Objects at the beginning of struct buffer.
+   If you add, remove, or reorder Lisp_Objects within buffer
+   structure, make sure that this is still correct.  */
+
+#define BUFFER_LISP_SIZE                                                \
+  ((offsetof (struct buffer, own_text) - header_size) / word_size)
+
+/* Size of the struct buffer part beyond leading Lisp_Objects, in word_size
+   units.  Rounding is needed for --with-wide-int configuration.  */
+
+#define BUFFER_REST_SIZE                                                \
+  ((((sizeof (struct buffer) - offsetof (struct buffer, own_text))      \
+     + (word_size - 1)) & ~(word_size - 1)) / word_size)
+
+/* Initialize the pseudovector header of buffer object.  BUFFER_LISP_SIZE
+   is required for GC, but BUFFER_REST_SIZE is set up just to be consistent
+   with other pseudovectors.  */
+
+#define BUFFER_PVEC_INIT(b)                                    \
+  XSETPVECTYPESIZE (b, PVEC_BUFFER, BUFFER_LISP_SIZE, BUFFER_REST_SIZE)
+
+/* Convenient check whether buffer B is live.  */
+
+#define BUFFER_LIVE_P(b) (!NILP (BVAR (b, name)))
+
+/* Verify indirection counters.  */
+
+#define BUFFER_CHECK_INDIRECTION(b)                     \
+  do {                                                  \
+    if (BUFFER_LIVE_P (b))                              \
+    {                                                   \
+      if (b->base_buffer)                               \
+        {                                               \
+          eassert (b->indirections == -1);              \
+          eassert (b->base_buffer->indirections > 0);   \
+        }                                               \
+      else                                              \
+        eassert (b->indirections >= 0);                 \
+    }                                                   \
+  } while (0)
+
+/* Chain of all buffers, including killed ones.  */
+
+extern struct buffer *all_buffers;
+
+/* Used to iterate over the chain above.  */
+
+#define FOR_EACH_BUFFER(b) \
+  for ((b) = all_buffers; (b); (b) = (b)->next)
+
 /* This points to the current buffer.  */
 
 extern struct buffer *current_buffer;
@@ -890,21 +1044,46 @@ extern struct buffer buffer_local_symbols;
 
 extern void delete_all_overlays (struct buffer *);
 extern void reset_buffer (struct buffer *);
-extern void evaporate_overlays (EMACS_INT);
-extern ptrdiff_t overlays_at (EMACS_INT pos, int extend, Lisp_Object **vec_ptr,
-                              ptrdiff_t *len_ptr, EMACS_INT *next_ptr,
-                              EMACS_INT *prev_ptr, int change_req);
+extern void compact_buffer (struct buffer *);
+extern void evaporate_overlays (ptrdiff_t);
+extern ptrdiff_t overlays_at (EMACS_INT, bool, Lisp_Object **,
+                              ptrdiff_t *, ptrdiff_t *, ptrdiff_t *, bool);
 extern ptrdiff_t sort_overlays (Lisp_Object *, ptrdiff_t, struct window *);
-extern void recenter_overlay_lists (struct buffer *, EMACS_INT);
-extern EMACS_INT overlay_strings (EMACS_INT, struct window *, unsigned char **);
+extern void recenter_overlay_lists (struct buffer *, ptrdiff_t);
+extern ptrdiff_t overlay_strings (ptrdiff_t, struct window *, unsigned char **);
 extern void validate_region (Lisp_Object *, Lisp_Object *);
-extern void set_buffer_internal (struct buffer *);
 extern void set_buffer_internal_1 (struct buffer *);
 extern void set_buffer_temp (struct buffer *);
+extern Lisp_Object buffer_local_value_1 (Lisp_Object, Lisp_Object);
 extern void record_buffer (Lisp_Object);
-extern void buffer_slot_type_mismatch (Lisp_Object, int) NO_RETURN;
-extern void fix_overlays_before (struct buffer *, EMACS_INT, EMACS_INT);
-extern void mmap_set_vars (int);
+extern _Noreturn void buffer_slot_type_mismatch (Lisp_Object, int);
+extern void fix_overlays_before (struct buffer *, ptrdiff_t, ptrdiff_t);
+extern void mmap_set_vars (bool);
+
+/* Set the current buffer to B.
+
+   We previously set windows_or_buffers_changed here to invalidate
+   global unchanged information in beg_unchanged and end_unchanged.
+   This is no longer necessary because we now compute unchanged
+   information on a buffer-basis.  Every action affecting other
+   windows than the selected one requires a select_window at some
+   time, and that increments windows_or_buffers_changed.  */
+
+BUFFER_INLINE void
+set_buffer_internal (struct buffer *b)
+{
+  if (current_buffer != b)
+    set_buffer_internal_1 (b);
+}
+
+/* Arrange to go back to the original buffer after the next
+   call to unbind_to if the original buffer is still alive.  */
+
+BUFFER_INLINE void
+record_unwind_current_buffer (void)
+{
+  record_unwind_protect (set_buffer_if_live, Fcurrent_buffer ());
+}
 
 /* Get overlays at POSN into array OVERLAYS with NOVERLAYS elements.
    If NEXTP is non-NULL, return next overlay there.
@@ -912,52 +1091,103 @@ extern void mmap_set_vars (int);
 
 #define GET_OVERLAYS_AT(posn, overlays, noverlays, nextp, chrq)         \
   do {                                                                  \
-    ptrdiff_t maxlen = 40;                                                      \
-    overlays = (Lisp_Object *) alloca (maxlen * sizeof (Lisp_Object));  \
+    ptrdiff_t maxlen = 40;                                              \
+    overlays = alloca (maxlen * sizeof *overlays);                      \
     noverlays = overlays_at (posn, 0, &overlays, &maxlen,               \
-                             nextp, NULL, chrq);                                \
+                             nextp, NULL, chrq);                        \
     if (noverlays > maxlen)                                             \
       {                                                                 \
         maxlen = noverlays;                                             \
-        overlays = (Lisp_Object *) alloca (maxlen * sizeof (Lisp_Object)); \
+        overlays = alloca (maxlen * sizeof *overlays);                  \
         noverlays = overlays_at (posn, 0, &overlays, &maxlen,           \
                                  nextp, NULL, chrq);                    \
       }                                                                 \
   } while (0)
 
-EXFUN (Fbuffer_live_p, 1);
-EXFUN (Fbuffer_name, 1);
-EXFUN (Fnext_overlay_change, 1);
-EXFUN (Fbuffer_local_value, 2);
-
 extern Lisp_Object Qbefore_change_functions;
 extern Lisp_Object Qafter_change_functions;
 extern Lisp_Object Qfirst_change_hook;
 
-
-/* Overlays */
+/* Get text properties of B.  */
 
-/* 1 if the OV is an overlay object.  */
+BUFFER_INLINE INTERVAL
+buffer_intervals (struct buffer *b)
+{
+  eassert (b->text != NULL);
+  return b->text->intervals;
+}
+
+/* Set text properties of B to I.  */
+
+BUFFER_INLINE void
+set_buffer_intervals (struct buffer *b, INTERVAL i)
+{
+  eassert (b->text != NULL);
+  b->text->intervals = i;
+}
+
+/* Non-zero if current buffer has overlays.  */
+
+BUFFER_INLINE bool
+buffer_has_overlays (void)
+{
+  return current_buffer->overlays_before || current_buffer->overlays_after;
+}
+
+/* Return character code of multi-byte form at byte position POS.  If POS
+   doesn't point the head of valid multi-byte form, only the byte at
+   POS is returned.  No range checking.
+
+   WARNING: The character returned by this macro could be "unified"
+   inside STRING_CHAR, if the original character in the buffer belongs
+   to one of the Private Use Areas (PUAs) of codepoints that Emacs
+   uses to support non-unified CJK characters.  If that happens,
+   CHAR_BYTES will return a value that is different from the length of
+   the original multibyte sequence stored in the buffer.  Therefore,
+   do _not_ use FETCH_MULTIBYTE_CHAR if you need to advance through
+   the buffer to the next character after fetching this one.  Instead,
+   use either FETCH_CHAR_ADVANCE or STRING_CHAR_AND_LENGTH.  */
+
+BUFFER_INLINE int
+FETCH_MULTIBYTE_CHAR (ptrdiff_t pos)
+{
+  unsigned char *p = ((pos >= GPT_BYTE ? GAP_SIZE : 0)
+                      + pos + BEG_ADDR - BEG_BYTE);
+  return STRING_CHAR (p);
+}
 
-#define OVERLAY_VALID(OV) (OVERLAYP (OV))
+/* Return character code of multi-byte form at byte position POS in BUF.
+   If POS doesn't point the head of valid multi-byte form, only the byte at
+   POS is returned.  No range checking.  */
+
+BUFFER_INLINE int
+BUF_FETCH_MULTIBYTE_CHAR (struct buffer *buf, ptrdiff_t pos)
+{
+  unsigned char *p
+    = ((pos >= BUF_GPT_BYTE (buf) ? BUF_GAP_SIZE (buf) : 0)
+       + pos + BUF_BEG_ADDR (buf) - BEG_BYTE);
+  return STRING_CHAR (p);
+}
+
+/* Overlays */
 
 /* Return the marker that stands for where OV starts in the buffer.  */
 
-#define OVERLAY_START(OV) (XOVERLAY (OV)->start)
+#define OVERLAY_START(OV) XOVERLAY (OV)->start
 
 /* Return the marker that stands for where OV ends in the buffer.  */
 
-#define OVERLAY_END(OV) (XOVERLAY (OV)->end)
+#define OVERLAY_END(OV) XOVERLAY (OV)->end
 
 /* Return the plist of overlay OV.  */
 
-#define OVERLAY_PLIST(OV) XOVERLAY ((OV))->plist
+#define OVERLAY_PLIST(OV) XOVERLAY (OV)->plist
 
 /* Return the actual buffer position for the marker P.
    We assume you know which buffer it's pointing into.  */
 
 #define OVERLAY_POSITION(P) \
- (MARKERP (P) ? marker_position (P) : (abort (), 0))
+ (MARKERP (P) ? marker_position (P) : (emacs_abort (), 0))
 
 
 /***********************************************************************
@@ -972,7 +1202,16 @@ extern int last_per_buffer_idx;
    from the start of a buffer structure.  */
 
 #define PER_BUFFER_VAR_OFFSET(VAR) \
-  offsetof (struct buffer, BUFFER_INTERNAL_FIELD (VAR))
+  offsetof (struct buffer, INTERNAL_FIELD (VAR))
+
+/* Used to iterate over normal Lisp_Object fields of struct buffer (all
+   Lisp_Objects except undo_list).  If you add, remove, or reorder
+   Lisp_Objects in a struct buffer, make sure that this is still correct.  */
+
+#define FOR_EACH_PER_BUFFER_OBJECT_AT(offset)                            \
+  for (offset = PER_BUFFER_VAR_OFFSET (name);                            \
+       offset <= PER_BUFFER_VAR_OFFSET (cursor_in_non_selected_windows); \
+       offset += word_size)
 
 /* Return the index of buffer-local variable VAR.  Each per-buffer
    variable has an index > 0 associated with it, except when it always
@@ -988,7 +1227,7 @@ extern int last_per_buffer_idx;
 
 #define PER_BUFFER_VALUE_P(B, IDX)              \
     (((IDX) < 0 || IDX >= last_per_buffer_idx)  \
-     ? (abort (), 0)                            \
+     ? (emacs_abort (), 0)                      \
      : ((B)->local_flags[IDX] != 0))
 
 /* Set whether per-buffer variable with index IDX has a buffer-local
@@ -997,7 +1236,7 @@ extern int last_per_buffer_idx;
 #define SET_PER_BUFFER_VALUE_P(B, IDX, VAL)     \
      do {                                               \
        if ((IDX) < 0 || (IDX) >= last_per_buffer_idx)   \
-         abort ();                                      \
+         emacs_abort ();                                \
        (B)->local_flags[IDX] = (VAL);                   \
      } while (0)
 
@@ -1025,20 +1264,38 @@ extern int last_per_buffer_idx;
 #define PER_BUFFER_IDX(OFFSET) \
       XINT (*(Lisp_Object *)((OFFSET) + (char *) &buffer_local_flags))
 
-/* Return the default value of the per-buffer variable at offset
-   OFFSET in the buffer structure.  */
+/* Functions to get and set default value of the per-buffer
+   variable at offset OFFSET in the buffer structure.  */
+
+BUFFER_INLINE Lisp_Object
+per_buffer_default (int offset)
+{
+  return *(Lisp_Object *)(offset + (char *) &buffer_defaults);
+}
 
-#define PER_BUFFER_DEFAULT(OFFSET) \
-      (*(Lisp_Object *)((OFFSET) + (char *) &buffer_defaults))
+BUFFER_INLINE void
+set_per_buffer_default (int offset, Lisp_Object value)
+{
+  *(Lisp_Object *)(offset + (char *) &buffer_defaults) = value;
+}
 
-/* Return the buffer-local value of the per-buffer variable at offset
-   OFFSET in the buffer structure.  */
+/* Functions to get and set buffer-local value of the per-buffer
+   variable at offset OFFSET in the buffer structure.  */
+
+BUFFER_INLINE Lisp_Object
+per_buffer_value (struct buffer *b, int offset)
+{
+  return *(Lisp_Object *)(offset + (char *) b);
+}
+
+BUFFER_INLINE void
+set_per_buffer_value (struct buffer *b, int offset, Lisp_Object value)
+{
+  *(Lisp_Object *)(offset + (char *) b) = value;
+}
 
-#define PER_BUFFER_VALUE(BUFFER, OFFSET) \
-      (*(Lisp_Object *)((OFFSET) + (char *) (BUFFER)))
-
 /* Downcase a character C, or make no change if that cannot be done.  */
-static inline int
+BUFFER_INLINE int
 downcase (int c)
 {
   Lisp_Object downcase_table = BVAR (current_buffer, downcase_table);
@@ -1047,10 +1304,10 @@ downcase (int c)
 }
 
 /* 1 if C is upper case.  */
-static inline int uppercasep (int c) { return downcase (c) != c; }
+BUFFER_INLINE bool uppercasep (int c) { return downcase (c) != c; }
 
 /* Upcase a character C known to be not upper case.  */
-static inline int
+BUFFER_INLINE int
 upcase1 (int c)
 {
   Lisp_Object upcase_table = BVAR (current_buffer, upcase_table);
@@ -1059,8 +1316,13 @@ upcase1 (int c)
 }
 
 /* 1 if C is lower case.  */
-static inline int lowercasep (int c)
-{ return !uppercasep (c) && upcase1 (c) != c; }
+BUFFER_INLINE bool
+lowercasep (int c)
+{
+  return !uppercasep (c) && upcase1 (c) != c;
+}
 
 /* Upcase a character C, or make no change if that cannot be done.  */
-static inline int upcase (int c) { return uppercasep (c) ? c : upcase1 (c); }
+BUFFER_INLINE int upcase (int c) { return uppercasep (c) ? c : upcase1 (c); }
+
+INLINE_HEADER_END