Support bidi reordering of text covered by display properties.

 src/bidi.c (bidi_copy_it): Use offsetof instead of emulating it.
 (bidi_fetch_char, bidi_fetch_char_advance): New functions.
 (bidi_cache_search, bidi_cache_iterator_state)
 (bidi_paragraph_init, bidi_resolve_explicit, bidi_resolve_weak)
 (bidi_level_of_next_char, bidi_move_to_visually_next): Support
 character positions inside a run of characters covered by a
 display string.
 (bidi_paragraph_init, bidi_resolve_explicit_1)
 (bidi_level_of_next_char): Call bidi_fetch_char and
 bidi_fetch_char_advance instead of FETCH_CHAR and
 FETCH_CHAR_ADVANCE.
 (bidi_init_it): Initialize new members.
 (LRE_CHAR, RLE_CHAR, PDF_CHAR, LRO_CHAR, RLO_CHAR): Remove macro
 definitions.
 (bidi_explicit_dir_char): Lookup character type in bidi_type_table,
 instead of using explicit *_CHAR codes.
 (bidi_resolve_explicit, bidi_resolve_weak): Use
 FETCH_MULTIBYTE_CHAR instead of FETCH_CHAR, as reordering of
 bidirectional text is supported only in multibyte buffers.
 (bidi_init_it): Accept additional argument FRAME_WINDOW_P and use
 it to initialize the frame_window_p member of struct bidi_it.
 (bidi_cache_iterator_state, bidi_resolve_explicit_1)
 (bidi_resolve_explicit, bidi_resolve_weak)
 (bidi_level_of_next_char, bidi_move_to_visually_next): Abort if
 bidi_it->nchars is non-positive.
 (bidi_level_of_next_char): Don't try to lookup the cache for the
 next/previous character if nothing is cached there yet, or if we
 were just reseat()'ed to a new position.
 src/xdisp.c (set_cursor_from_row): Set start and stop points
 according to the row's direction when priming the loop that looks
 for the glyph on which to display cursor.
 (single_display_spec_intangible_p): Function deleted.
 (display_prop_intangible_p): Reimplement to call
 handle_display_spec instead of single_display_spec_intangible_p.
 Accept 3 additional arguments needed by handle_display_spec.  This
 fixes incorrect cursor motion across display property with complex
 values: lists, `(when COND...)' forms, etc.
 (single_display_spec_string_p): Support property values that are
 lists with the argument STRING its top-level element.
 (display_prop_string_p): Fix the condition for processing a
 property that is a list to be consistent with handle_display_spec.
 (handle_display_spec): New function, refactored from the
 last portion of handle_display_prop.
 (compute_display_string_pos): Accept additional argument
 FRAME_WINDOW_P.  Call handle_display_spec to determine whether the
 value of a `display' property is a "replacing spec".
 (handle_single_display_spec): Accept 2 additional arguments BUFPOS
 and FRAME_WINDOW_P.  If IT is NULL, don't set up the iterator from
 the display property, but just return a value indicating whether
 the display property will replace the characters it covers.
 (Fcurrent_bidi_paragraph_direction): Initialize the nchars and
 frame_window_p members of struct bidi_it.
 (compute_display_string_pos, compute_display_string_end): New
 functions.
 (push_it): Accept second argument POSITION, where pop_it should
 jump to continue iteration.
 (reseat_1): Initialize bidi_it.disp_pos.
 src/keyboard.c (adjust_point_for_property): Adjust the call to
 display_prop_intangible_p to its new signature.
 src/dispextern.h (struct bidi_it): New member frame_window_p.
 (bidi_init_it): Update prototypes.
 (display_prop_intangible_p): Update prototype.
 (compute_display_string_pos, compute_display_string_end): Declare
 prototypes.
 (struct bidi_it): New members nchars and disp_pos.  ch_len is now
 EMACS_INT.

1 files changed, 74 insertions, 0 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 45d8e38738a..4c33bcc4e67 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,77 @@
+2011-06-03  Eli Zaretskii  <eliz@gnu.org>
+
+        Support bidi reordering of text covered by display properties.
+
+        * bidi.c (bidi_copy_it): Use offsetof instead of emulating it.
+        (bidi_fetch_char, bidi_fetch_char_advance): New functions.
+        (bidi_cache_search, bidi_cache_iterator_state)
+        (bidi_paragraph_init, bidi_resolve_explicit, bidi_resolve_weak)
+        (bidi_level_of_next_char, bidi_move_to_visually_next): Support
+        character positions inside a run of characters covered by a
+        display string.
+        (bidi_paragraph_init, bidi_resolve_explicit_1)
+        (bidi_level_of_next_char): Call bidi_fetch_char and
+        bidi_fetch_char_advance instead of FETCH_CHAR and
+        FETCH_CHAR_ADVANCE.
+        (bidi_init_it): Initialize new members.
+        (LRE_CHAR, RLE_CHAR, PDF_CHAR, LRO_CHAR, RLO_CHAR): Remove macro
+        definitions.
+        (bidi_explicit_dir_char): Lookup character type in bidi_type_table,
+        instead of using explicit *_CHAR codes.
+        (bidi_resolve_explicit, bidi_resolve_weak): Use
+        FETCH_MULTIBYTE_CHAR instead of FETCH_CHAR, as reordering of
+        bidirectional text is supported only in multibyte buffers.
+        (bidi_init_it): Accept additional argument FRAME_WINDOW_P and use
+        it to initialize the frame_window_p member of struct bidi_it.
+        (bidi_cache_iterator_state, bidi_resolve_explicit_1)
+        (bidi_resolve_explicit, bidi_resolve_weak)
+        (bidi_level_of_next_char, bidi_move_to_visually_next): Abort if
+        bidi_it->nchars is non-positive.
+        (bidi_level_of_next_char): Don't try to lookup the cache for the
+        next/previous character if nothing is cached there yet, or if we
+        were just reseat()'ed to a new position.
+
+        * xdisp.c (set_cursor_from_row): Set start and stop points
+        according to the row's direction when priming the loop that looks
+        for the glyph on which to display cursor.
+        (single_display_spec_intangible_p): Function deleted.
+        (display_prop_intangible_p): Reimplement to call
+        handle_display_spec instead of single_display_spec_intangible_p.
+        Accept 3 additional arguments needed by handle_display_spec.  This
+        fixes incorrect cursor motion across display property with complex
+        values: lists, `(when COND...)' forms, etc.
+        (single_display_spec_string_p): Support property values that are
+        lists with the argument STRING its top-level element.
+        (display_prop_string_p): Fix the condition for processing a
+        property that is a list to be consistent with handle_display_spec.
+        (handle_display_spec): New function, refactored from the
+        last portion of handle_display_prop.
+        (compute_display_string_pos): Accept additional argument
+        FRAME_WINDOW_P.  Call handle_display_spec to determine whether the
+        value of a `display' property is a "replacing spec".
+        (handle_single_display_spec): Accept 2 additional arguments BUFPOS
+        and FRAME_WINDOW_P.  If IT is NULL, don't set up the iterator from
+        the display property, but just return a value indicating whether
+        the display property will replace the characters it covers.
+        (Fcurrent_bidi_paragraph_direction): Initialize the nchars and
+        frame_window_p members of struct bidi_it.
+        (compute_display_string_pos, compute_display_string_end): New
+        functions.
+        (push_it): Accept second argument POSITION, where pop_it should
+        jump to continue iteration.
+        (reseat_1): Initialize bidi_it.disp_pos.
+
+        * keyboard.c (adjust_point_for_property): Adjust the call to
+        display_prop_intangible_p to its new signature.
+
+        * dispextern.h (struct bidi_it): New member frame_window_p.
+        (bidi_init_it): Update prototypes.
+        (display_prop_intangible_p): Update prototype.
+        (compute_display_string_pos, compute_display_string_end): Declare
+        prototypes.
+        (struct bidi_it): New members nchars and disp_pos.  ch_len is now
+        EMACS_INT.
+
 2011-06-02  Paul Eggert  <eggert@cs.ucla.edu>
 
         Malloc failure behavior now depends on size of allocation.