2 files changed, 24 insertions, 11 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 34f81336e6d..1ceb2ec3134 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2003-05-31  Kenichi Handa  <handa@m17n.org>
+
+        * charset.h (VALID_LEADING_CODE_P): New macro.
+        (UNIBYTE_STR_AS_MULTIBYTE_P): Check more rigidly.
+
 2003-05-30  Kenichi Handa  <handa@m17n.org>
 
         * coding.c (ccl_coding_driver): Set ccl->eight_bit_control
diff --git a/src/charset.h b/src/charset.h
index 97b9801464e..fd8905e47d8 100644
--- a/src/charset.h
+++ b/src/charset.h
@@ -441,21 +441,29 @@ extern int width_by_char_head[256];
 
 #endif /* not BYTE_COMBINING_DEBUG */
 
+#define VALID_LEADING_CODE_P(code)      \
+  (! NILP (CHARSET_TABLE_ENTRY (code)))
+
 /* Return 1 iff the byte sequence at unibyte string STR (LENGTH bytes)
    is valid as a multibyte form.  If valid, by a side effect, BYTES is
    set to the byte length of the multibyte form.  */
 
-#define UNIBYTE_STR_AS_MULTIBYTE_P(str, length, bytes)  \
-  (((str)[0] < 0x80 || (str)[0] >= 0xA0)                \
-   ? ((bytes) = 1)                                      \
-   : (((bytes) = BYTES_BY_CHAR_HEAD ((str)[0])),        \
-      ((bytes) > 1 && (bytes) <= (length)               \
-       && (str)[0] != LEADING_CODE_8_BIT_CONTROL        \
-       && !CHAR_HEAD_P ((str)[1])                       \
-       && ((bytes) == 2                                 \
-           || (!CHAR_HEAD_P ((str)[2])                  \
-               && ((bytes) == 3                         \
-                   || !CHAR_HEAD_P ((str)[3])))))))
+#define UNIBYTE_STR_AS_MULTIBYTE_P(str, length, bytes)          \
+  (((str)[0] < 0x80 || (str)[0] >= 0xA0)                        \
+   ? ((bytes) = 1)                                              \
+   : (((bytes) = BYTES_BY_CHAR_HEAD ((str)[0])),                \
+      ((bytes) <= (length)                                      \
+       && !CHAR_HEAD_P ((str)[1])                               \
+       && ((bytes) == 2                                         \
+           ? (str)[0] != LEADING_CODE_8_BIT_CONTROL             \
+           : (!CHAR_HEAD_P ((str)[2])                           \
+              && ((bytes) == 3                                  \
+                  ? (((str)[0] != LEADING_CODE_PRIVATE_11       \
+                      && (str)[0] != LEADING_CODE_PRIVATE_12)   \
+                     || VALID_LEADING_CODE_P (str[1]))          \
+                  : (!CHAR_HEAD_P ((str)[3])                    \
+                     && VALID_LEADING_CODE_P (str[1]))))))))
+
 
 /* Return 1 iff the byte sequence at multibyte string STR is valid as
    a unibyte form.  By a side effect, BYTES is set to the byte length