Fix bug #16043 with crashes when displaying new bidi control characters.

 src/bidi.c (bidi_get_type, bidi_get_category): Handle the isolate
 directional control characters.  Update type and category
 determination according to the UBA from Unicode v6.3.
 (bidi_category_t): New category EXPLICIT_FORMATTING.
 src/dispextern.h (bidi_type_t): Update to include new bidirectional
 properties introduced with Unicode v6.3.

 admin/unidata/unidata-gen.el (unidata-prop-alist): Update bidi-class
 to include the new isolate-related classes introduced with Unicode
 v6.3.
 (unidata-encode-val): Accept an additional optional argument, a
 warning message to emit when UnicodeData.txt defines bidi-class
 values that are not in unidata-prop-alist.  Add a comment
 explaining what should maintainers do if/when such a warning ever
 appears.
 (unidata-gen-table): Call unidata-encode-val with 3rd arg non-nil
 when generating uni-bidi.el.

5 files changed, 87 insertions, 30 deletions

diff --git a/admin/ChangeLog b/admin/ChangeLog
index 7d23542a84e..730253e616f 100644
--- a/admin/ChangeLog
+++ b/admin/ChangeLog
@@ -1,3 +1,16 @@
+2013-12-04  Eli Zaretskii  <eliz@gnu.org>
+
+        * unidata/unidata-gen.el (unidata-prop-alist): Update bidi-class
+        to include the new isolate-related classes introduced with Unicode
+        v6.3.
+        (unidata-encode-val): Accept an additional optional argument, a
+        warning message to emit when UnicodeData.txt defines bidi-class
+        values that are not in unidata-prop-alist.  Add a comment
+        explaining what should maintainers do if/when such a warning ever
+        appears.
+        (unidata-gen-table): Call unidata-encode-val with 3rd arg non-nil
+        when generating uni-bidi.el.
+
 2013-12-01  Glenn Morris  <rgm@gnu.org>
 
         * unidata/Makefile.in (${DSTDIR}/charprop.el):
diff --git a/admin/unidata/unidata-gen.el b/admin/unidata/unidata-gen.el
index 42e1cc0bc3c..fa8f81636e3 100644
--- a/admin/unidata/unidata-gen.el
+++ b/admin/unidata/unidata-gen.el
@@ -194,8 +194,8 @@ Property value is an integer."
      4 unidata-gen-table-symbol "uni-bidi.el"
      "Unicode bidi class.
 Property value is one of the following symbols:
-  L, LRE, LRO, R, AL, RLE, RLO, PDF, EN, ES, ET,
-  AN, CS, NSM, BN, B, S, WS, ON"
+  L, LRE, LRO, LRI, R, AL, RLE, RLO, RLI, FSI, PDF, PDI,
+  EN, ES, ET, AN, CS, NSM, BN, B, S, WS, ON"
      unidata-describe-bidi-class
      ;; The assignment of default values to blocks of code points
      ;; follows the file DerivedBidiClass.txt from the Unicode
@@ -205,7 +205,8 @@ Property value is one of the following symbols:
         (#xFB1D #xFB4F R) (#x10800 #x10FFF R) (#x1E800 #x1EFFF R))
      ;; The order of elements must be in sync with bidi_type_t in
      ;; src/dispextern.h.
-     (L R EN AN BN B AL LRE LRO RLE RLO PDF ES ET CS NSM S WS ON))
+     (L R EN AN BN B AL LRE LRO RLE RLO PDF LRI RLI FSI PDI
+        ES ET CS NSM S WS ON))
     (decomposition
      5 unidata-gen-table-decomposition "uni-decomposition.el"
      "Unicode decomposition mapping.
@@ -397,12 +398,17 @@ is the character itself.")))
 ;; If VAL is one of VALn, just return n.
 ;; Otherwise, VAL-LIST is modified to this:
 ;;   ((nil . 0) (VAL1 . 1) (VAL2 . 2) ... (VAL . n+1))
+;;
+;; WARN is an optional warning to display when the value list is
+;; extended, for property values that need to be in sync with other
+;; parts of Emacs; currently only used for bidi-class.
 
-(defun unidata-encode-val (val-list val)
+(defun unidata-encode-val (val-list val &optional warn)
   (let ((slot (assoc val val-list))
         val-code)
     (if slot
         (cdr slot)
+      (if warn (message warn val))
       (setq val-code (length val-list))
       (nconc val-list (list (cons val val-code)))
       val-code)))
@@ -413,6 +419,16 @@ is the character itself.")))
   (let ((table (make-char-table 'char-code-property-table))
         (prop-idx (unidata-prop-index prop))
         (vec (make-vector 128 0))
+        ;; When this warning is printed, there's a need to make the
+        ;; following changes:
+        ;; (1) update unidata-prop-alist with the new bidi-class values;
+        ;; (2) extend bidi_type_t enumeration on src/dispextern.h to
+        ;;     include the new classes;
+        ;; (3) possibly update the assertion in bidi.c:bidi_check_type; and
+        ;; (4) possibly update the switch cases in
+        ;;     bidi.c:bidi_get_type and bidi.c:bidi_get_category.
+        (bidi-warning "\
+** Found new bidi-class '%s', please update bidi.c and dispextern.h")
         tail elt range val val-code idx slot
         prev-range-data)
     (setq val-list (cons nil (copy-sequence val-list)))
@@ -438,7 +454,9 @@ is the character itself.")))
       (setq elt (car tail) tail (cdr tail))
       (setq range (car elt)
             val (funcall val-func (nth prop-idx elt)))
-      (setq val-code (if val (unidata-encode-val val-list val)))
+      (setq val-code (if val (unidata-encode-val val-list val
+                                                 (and (eq prop 'bidi-class)
+                                                      bidi-warning))))
       (if (consp range)
           (when val-code
             (set-char-table-range table range val-code)
@@ -486,7 +504,9 @@ is the character itself.")))
             (setq new-val (funcall val-func (nth prop-idx elt)))
             (if (not (eq val new-val))
                 (setq val new-val
-                      val-code (if val (unidata-encode-val val-list val))))
+                      val-code (if val (unidata-encode-val
+                                        val-list val (and (eq prop 'bidi-class)
+                                                          bidi-warning)))))
             (if val-code
                 (aset vec (- range start) val-code))
             (setq tail (cdr tail)))
diff --git a/src/ChangeLog b/src/ChangeLog
index a877bc885e7..4c7b3015877 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,13 @@
+2013-12-04  Eli Zaretskii  <eliz@gnu.org>
+
+        * bidi.c (bidi_get_type, bidi_get_category): Handle the isolate
+        directional control characters.  Update type and category
+        determination according to the UBA from Unicode v6.3.
+        (bidi_category_t): New category EXPLICIT_FORMATTING.
+
+        * dispextern.h (bidi_type_t): Update to include new bidirectional
+        properties introduced with Unicode v6.3.  (Bug#16043)
+
 2013-12-04  Martin Rudalics  <rudalics@gmx.at>
 
         * xterm.c (XTflash): Fix coordinate of bottom area to flash
diff --git a/src/bidi.c b/src/bidi.c
index 98c3c17b78f..d3a617651f6 100644
--- a/src/bidi.c
+++ b/src/bidi.c
@@ -76,7 +76,8 @@ typedef enum {
   UNKNOWN_BC,
   NEUTRAL,
   WEAK,
-  STRONG
+  STRONG,
+  EXPLICIT_FORMATTING
 } bidi_category_t;
 
 /* UAX#9 says to search only for L, AL, or R types of characters, and
@@ -115,13 +116,9 @@ bidi_get_type (int ch, bidi_dir_t override)
   if (default_type == UNKNOWN_BT)
     emacs_abort ();
 
-  if (override == NEUTRAL_DIR)
-    return default_type;
-
   switch (default_type)
     {
-      /* Although UAX#9 does not tell, it doesn't make sense to
-         override NEUTRAL_B and LRM/RLM characters.  */
+      case WEAK_BN:
       case NEUTRAL_B:
       case LRE:
       case LRO:
@@ -129,20 +126,20 @@ bidi_get_type (int ch, bidi_dir_t override)
       case RLO:
       case PDF:
         return default_type;
+        /* FIXME: The isolate controls are treated as BN until we add
+           support for UBA v6.3.  */
+      case LRI:
+      case RLI:
+      case FSI:
+      case PDI:
+        return WEAK_BN;
       default:
-        switch (ch)
-          {
-            case LRM_CHAR:
-            case RLM_CHAR:
-              return default_type;
-            default:
-              if (override == L2R) /* X6 */
-                return STRONG_L;
-              else if (override == R2L)
-                return STRONG_R;
-              else
-                emacs_abort (); /* can't happen: handled above */
-          }
+        if (override == L2R)
+          return STRONG_L;
+        else if (override == R2L)
+          return STRONG_R;
+        else
+          return default_type;
     }
 }
 
@@ -163,12 +160,7 @@ bidi_get_category (bidi_type_t type)
       case STRONG_L:
       case STRONG_R:
       case STRONG_AL:
-      case LRE:
-      case LRO:
-      case RLE:
-      case RLO:
         return STRONG;
-      case PDF:         /* ??? really?? */
       case WEAK_EN:
       case WEAK_ES:
       case WEAK_ET:
@@ -176,12 +168,30 @@ bidi_get_category (bidi_type_t type)
       case WEAK_CS:
       case WEAK_NSM:
       case WEAK_BN:
+        /* FIXME */
+      case LRI:
+      case RLI:
+      case FSI:
+      case PDI:
         return WEAK;
       case NEUTRAL_B:
       case NEUTRAL_S:
       case NEUTRAL_WS:
       case NEUTRAL_ON:
         return NEUTRAL;
+      case LRE:
+      case LRO:
+      case RLE:
+      case RLO:
+      case PDF:
+#if 0
+        /* FIXME: This awaits implementation of isolate support.  */
+      case LRI:
+      case RLI:
+      case FSI:
+      case PDI:
+#endif
+        return EXPLICIT_FORMATTING;
       default:
         emacs_abort ();
     }
diff --git a/src/dispextern.h b/src/dispextern.h
index 2ce0a8f4c99..7de4edf2196 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -1895,6 +1895,10 @@ typedef enum {
   RLE,          /* right-to-left embedding */
   RLO,          /* right-to-left override */
   PDF,          /* pop directional format */
+  LRI,          /* left-to-right isolate */
+  RLI,          /* right-to-left isolate */
+  FSI,          /* first strong isolate */
+  PDI,          /* pop directional isolate */
   WEAK_ES,      /* european number separator */
   WEAK_ET,      /* european number terminator */
   WEAK_CS,      /* common separator */