Generalize run-time debugging checks.

[bpt/emacs.git] / src / bidi.c

diff --git a/src/bidi.c b/src/bidi.c
index bd78a5e..80986e5 100644 (file)
--- a/src/bidi.c
+++ b/src/bidi.c
@@ -1,5 +1,5 @@
 /* Low-level bidirectional buffer/string-scanning functions for GNU Emacs.
-   Copyright (C) 2000-2001, 2004-2005, 2009-2011
+   Copyright (C) 2000-2001, 2004-2005, 2009-2012
    Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
@@ -59,8 +59,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <setjmp.h>
 
 #include "lisp.h"
-#include "buffer.h"
 #include "character.h"
+#include "buffer.h"
 #include "dispextern.h"
 
 static int bidi_initialized = 0;
@@ -149,7 +149,7 @@ bidi_get_type (int ch, bidi_dir_t override)
 static inline void
 bidi_check_type (bidi_type_t type)
 {
-  xassert (UNKNOWN_BT <= type && type <= NEUTRAL_ON);
+  eassert (UNKNOWN_BT <= type && type <= NEUTRAL_ON);
 }
 
 /* Given a bidi TYPE of a character, return its category.  */
@@ -204,8 +204,16 @@ bidi_mirror_char (int c)
   val = CHAR_TABLE_REF (bidi_mirror_table, c);
   if (INTEGERP (val))
     {
-      EMACS_INT v = XINT (val);
+      int v;
+
+      /* When debugging, check before assigning to V, so that the check
+        isn't broken by undefined behavior due to int overflow.  */
+      eassert (CHAR_VALID_P (XINT (val)));
 
+      v = XINT (val);
+
+      /* Minimal test we must do in optimized builds, to prevent weird
+        crashes further down the road.  */
       if (v < 0 || v > MAX_CHAR)
        abort ();
 
@@ -255,7 +263,7 @@ bidi_push_embedding_level (struct bidi_it *bidi_it,
                           int level, bidi_dir_t override)
 {
   bidi_it->stack_idx++;
-  xassert (bidi_it->stack_idx < BIDI_MAXLEVEL);
+  eassert (bidi_it->stack_idx < BIDI_MAXLEVEL);
   bidi_it->level_stack[bidi_it->stack_idx].level = level;
   bidi_it->level_stack[bidi_it->stack_idx].override = override;
 }
@@ -450,7 +458,7 @@ bidi_cache_find_level_change (int level, int dir, int before)
       ptrdiff_t i = dir ? bidi_cache_last_idx : bidi_cache_idx - 1;
       int incr = before ? 1 : 0;
 
-      xassert (!dir || bidi_cache_last_idx >= 0);
+      eassert (!dir || bidi_cache_last_idx >= 0);
 
       if (!dir)
        dir = -1;
@@ -572,7 +580,7 @@ bidi_cache_find (ptrdiff_t charpos, int level, struct bidi_it *bidi_it)
 
       bidi_copy_it (bidi_it, &bidi_cache[i]);
       bidi_cache_last_idx = i;
-      /* Don't let scan direction from from the cached state override
+      /* Don't let scan direction from the cached state override
         the current scan direction.  */
       bidi_it->scan_dir = current_scan_dir;
       return bidi_it->type;
@@ -608,7 +616,7 @@ bidi_push_it (struct bidi_it *bidi_it)
   memcpy (&bidi_cache[bidi_cache_idx++], bidi_it, sizeof (struct bidi_it));
 
   /* Push the current cache start onto the stack.  */
-  xassert (bidi_cache_sp < IT_STACK_SIZE);
+  eassert (bidi_cache_sp < IT_STACK_SIZE);
   bidi_cache_start_stack[bidi_cache_sp++] = bidi_cache_start;
 
   /* Start a new level of cache, and make it empty.  */
@@ -932,6 +940,7 @@ bidi_fetch_char (ptrdiff_t bytepos, ptrdiff_t charpos, ptrdiff_t *disp_pos,
   ptrdiff_t endpos
     = (string->s || STRINGP (string->lstring)) ? string->schars : ZV;
   struct text_pos pos;
+  int len;
 
   /* If we got past the last known position of display string, compute
      the position of the next one.  That position could be at CHARPOS.  */
@@ -1003,7 +1012,6 @@ bidi_fetch_char (ptrdiff_t bytepos, ptrdiff_t charpos, ptrdiff_t *disp_pos,
     normal_char:
       if (string->s)
        {
-         int len;
 
          if (!string->unibyte)
            {
@@ -1018,8 +1026,6 @@ bidi_fetch_char (ptrdiff_t bytepos, ptrdiff_t charpos, ptrdiff_t *disp_pos,
        }
       else if (STRINGP (string->lstring))
        {
-         int len;
-
          if (!string->unibyte)
            {
              ch = STRING_CHAR_AND_LENGTH (SDATA (string->lstring) + bytepos,
@@ -1034,8 +1040,8 @@ bidi_fetch_char (ptrdiff_t bytepos, ptrdiff_t charpos, ptrdiff_t *disp_pos,
        }
       else
        {
-         ch = FETCH_MULTIBYTE_CHAR (bytepos);
-         *ch_len = CHAR_BYTES (ch);
+         ch = STRING_CHAR_AND_LENGTH (BYTE_POS_ADDR (bytepos), len);
+         *ch_len = len;
        }
       *nchars = 1;
     }
@@ -1132,7 +1138,7 @@ bidi_find_paragraph_start (ptrdiff_t pos, ptrdiff_t pos_byte)
 
    Note that this function gives the paragraph separator the same
    direction as the preceding paragraph, even though Emacs generally
-   views the separartor as not belonging to any paragraph.  */
+   views the separator as not belonging to any paragraph.  */
 void
 bidi_paragraph_init (bidi_dir_t dir, struct bidi_it *bidi_it, int no_default_p)
 {
@@ -1952,7 +1958,7 @@ bidi_resolve_neutral (struct bidi_it *bidi_it)
              case STRONG_AL:
                /* Actually, STRONG_AL cannot happen here, because
                   bidi_resolve_weak converts it to STRONG_R, per W3.  */
-               xassert (type != STRONG_AL);
+               eassert (type != STRONG_AL);
                next_type = type;
                break;
              case WEAK_EN: