From: K.Kosako <kkosako0@gmail.com>
Date: Sat, 27 Aug 2016 08:52:30 +0000 (+0900)
Subject: add is_valid_mbc_string() member into OnigEncodingType
X-Git-Tag: v6.1.0~11
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=42dcb6b0daf8bff19aacc268e3dc3e759e9a25d5;p=onig

add is_valid_mbc_string() member into OnigEncodingType
---

diff --git a/src/ascii.c b/src/ascii.c
index 92db179..b21878d 100644
--- a/src/ascii.c
+++ b/src/ascii.c
@@ -56,5 +56,6 @@ OnigEncodingType OnigEncodingASCII = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/big5.c b/src/big5.c
index 3c90eaa..3d44975 100644
--- a/src/big5.c
+++ b/src/big5.c
@@ -54,6 +54,12 @@ big5_mbc_enc_len(const UChar* p)
   return EncLen_BIG5[*p];
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_BIG5, s, end);
+}
+
 static OnigCodePoint
 big5_mbc_to_code(const UChar* p, const UChar* end)
 {
@@ -160,5 +166,6 @@ OnigEncodingType OnigEncodingBIG5 = {
   big5_left_adjust_char_head,
   big5_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/cp1251.c b/src/cp1251.c
index af45847..4d655bb 100644
--- a/src/cp1251.c
+++ b/src/cp1251.c
@@ -198,5 +198,6 @@ OnigEncodingType OnigEncodingCP1251 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/euc_jp.c b/src/euc_jp.c
index 17f53e7..19422ce 100644
--- a/src/euc_jp.c
+++ b/src/euc_jp.c
@@ -56,6 +56,12 @@ mbc_enc_len(const UChar* p)
   return EncLen_EUCJP[*p];
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_EUC_JP, s, end);
+}
+
 static OnigCodePoint
 mbc_to_code(const UChar* p, const UChar* end)
 {
@@ -269,5 +275,6 @@ OnigEncodingType OnigEncodingEUC_JP = {
   left_adjust_char_head,
   is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/euc_kr.c b/src/euc_kr.c
index 769104b..12803cd 100644
--- a/src/euc_kr.c
+++ b/src/euc_kr.c
@@ -54,6 +54,12 @@ euckr_mbc_enc_len(const UChar* p)
   return EncLen_EUCKR[*p];
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_EUC_KR, s, end);
+}
+
 static OnigCodePoint
 euckr_mbc_to_code(const UChar* p, const UChar* end)
 {
@@ -136,7 +142,8 @@ OnigEncodingType OnigEncodingEUC_KR = {
   euckr_left_adjust_char_head,
   euckr_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
 
 /* Same with OnigEncodingEUC_KR except the name */
@@ -158,5 +165,6 @@ OnigEncodingType OnigEncodingEUC_CN = {
   euckr_left_adjust_char_head,
   euckr_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/euc_tw.c b/src/euc_tw.c
index f757961..4e07567 100644
--- a/src/euc_tw.c
+++ b/src/euc_tw.c
@@ -54,6 +54,12 @@ euctw_mbc_enc_len(const UChar* p)
   return EncLen_EUCTW[*p];
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_EUC_TW, s, end);
+}
+
 static OnigCodePoint
 euctw_mbc_to_code(const UChar* p, const UChar* end)
 {
@@ -127,5 +133,6 @@ OnigEncodingType OnigEncodingEUC_TW = {
   euctw_left_adjust_char_head,
   euctw_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/gb18030.c b/src/gb18030.c
index beeda06..36fc3de 100644
--- a/src/gb18030.c
+++ b/src/gb18030.c
@@ -75,6 +75,12 @@ gb18030_mbc_enc_len(const UChar* p)
   return 2;
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_GB18030, s, end);
+}
+
 static OnigCodePoint
 gb18030_mbc_to_code(const UChar* p, const UChar* end)
 {
@@ -493,5 +499,6 @@ OnigEncodingType OnigEncodingGB18030 = {
   gb18030_left_adjust_char_head,
   gb18030_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/iso8859_1.c b/src/iso8859_1.c
index b2d8c9a..573931f 100644
--- a/src/iso8859_1.c
+++ b/src/iso8859_1.c
@@ -270,5 +270,6 @@ OnigEncodingType OnigEncodingISO_8859_1 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_10.c b/src/iso8859_10.c
index a6dbe5c..91b18d4 100644
--- a/src/iso8859_10.c
+++ b/src/iso8859_10.c
@@ -237,5 +237,6 @@ OnigEncodingType OnigEncodingISO_8859_10 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_11.c b/src/iso8859_11.c
index d671af8..518be25 100644
--- a/src/iso8859_11.c
+++ b/src/iso8859_11.c
@@ -94,5 +94,6 @@ OnigEncodingType OnigEncodingISO_8859_11 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_13.c b/src/iso8859_13.c
index c97e24e..d1f39a2 100644
--- a/src/iso8859_13.c
+++ b/src/iso8859_13.c
@@ -226,5 +226,6 @@ OnigEncodingType OnigEncodingISO_8859_13 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_14.c b/src/iso8859_14.c
index edf5313..3361b0d 100644
--- a/src/iso8859_14.c
+++ b/src/iso8859_14.c
@@ -239,5 +239,6 @@ OnigEncodingType OnigEncodingISO_8859_14 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_15.c b/src/iso8859_15.c
index 24aa573..b09e876 100644
--- a/src/iso8859_15.c
+++ b/src/iso8859_15.c
@@ -233,5 +233,6 @@ OnigEncodingType OnigEncodingISO_8859_15 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_16.c b/src/iso8859_16.c
index 4f4c2b8..29a350d 100644
--- a/src/iso8859_16.c
+++ b/src/iso8859_16.c
@@ -235,5 +235,6 @@ OnigEncodingType OnigEncodingISO_8859_16 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_2.c b/src/iso8859_2.c
index 16c1549..9eb3536 100644
--- a/src/iso8859_2.c
+++ b/src/iso8859_2.c
@@ -233,5 +233,6 @@ OnigEncodingType OnigEncodingISO_8859_2 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_3.c b/src/iso8859_3.c
index 549f01e..862823a 100644
--- a/src/iso8859_3.c
+++ b/src/iso8859_3.c
@@ -233,5 +233,6 @@ OnigEncodingType OnigEncodingISO_8859_3 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_4.c b/src/iso8859_4.c
index 74b3a88..db706da 100644
--- a/src/iso8859_4.c
+++ b/src/iso8859_4.c
@@ -235,5 +235,6 @@ OnigEncodingType OnigEncodingISO_8859_4 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_5.c b/src/iso8859_5.c
index 70c799a..0e03e9c 100644
--- a/src/iso8859_5.c
+++ b/src/iso8859_5.c
@@ -224,5 +224,6 @@ OnigEncodingType OnigEncodingISO_8859_5 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_6.c b/src/iso8859_6.c
index e36579a..6289af5 100644
--- a/src/iso8859_6.c
+++ b/src/iso8859_6.c
@@ -94,5 +94,6 @@ OnigEncodingType OnigEncodingISO_8859_6 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_7.c b/src/iso8859_7.c
index 87a1acd..75b520f 100644
--- a/src/iso8859_7.c
+++ b/src/iso8859_7.c
@@ -220,5 +220,6 @@ OnigEncodingType OnigEncodingISO_8859_7 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_8.c b/src/iso8859_8.c
index e34a3bb..5f18345 100644
--- a/src/iso8859_8.c
+++ b/src/iso8859_8.c
@@ -94,5 +94,6 @@ OnigEncodingType OnigEncodingISO_8859_8 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/iso8859_9.c b/src/iso8859_9.c
index 8cbbbd6..d0c06bb 100644
--- a/src/iso8859_9.c
+++ b/src/iso8859_9.c
@@ -226,5 +226,6 @@ OnigEncodingType OnigEncodingISO_8859_9 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/koi8.c b/src/koi8.c
index 9c11776..80f89e9 100644
--- a/src/koi8.c
+++ b/src/koi8.c
@@ -248,5 +248,6 @@ OnigEncodingType OnigEncodingKOI8 = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/koi8_r.c b/src/koi8_r.c
index 2f090f4..f8ef34f 100644
--- a/src/koi8_r.c
+++ b/src/koi8_r.c
@@ -210,5 +210,6 @@ OnigEncodingType OnigEncodingKOI8_R = {
   onigenc_single_byte_left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  onigenc_always_true_is_valid_mbc_string
 };
diff --git a/src/oniguruma.h b/src/oniguruma.h
index a09c9e9..8e4911d 100644
--- a/src/oniguruma.h
+++ b/src/oniguruma.h
@@ -165,6 +165,7 @@ typedef struct OnigEncodingTypeST {
   int    (*is_allowed_reverse_match)(const OnigUChar* p, const OnigUChar* end);
   int    (*init)(void);
   int    (*is_initialized)(void);
+  int    (*is_valid_mbc_string)(const OnigUChar* s, const OnigUChar* end);
 } OnigEncodingType;
 
 typedef OnigEncodingType* OnigEncoding;
@@ -279,6 +280,8 @@ ONIG_EXTERN OnigEncodingType OnigEncodingGB18030;
         (enc)->is_allowed_reverse_match(s,end)
 #define ONIGENC_LEFT_ADJUST_CHAR_HEAD(enc,start,s) \
         (enc)->left_adjust_char_head(start, s)
+#define ONIGENC_IS_VALID_MBC_STRING(enc,s,end) \
+        (enc)->is_valid_mbc_string(s,end)
 #define ONIGENC_APPLY_ALL_CASE_FOLD(enc,case_fold_flag,f,arg) \
         (enc)->apply_all_case_fold(case_fold_flag,f,arg)
 #define ONIGENC_GET_CASE_FOLD_CODES_BY_STR(enc,case_fold_flag,p,end,acs) \
diff --git a/src/regenc.c b/src/regenc.c
index 11745d3..4517848 100644
--- a/src/regenc.c
+++ b/src/regenc.c
@@ -2,7 +2,7 @@
   regenc.c -  Oniguruma (regular expression library)
 **********************************************************************/
 /*-
- * Copyright (c) 2002-2007  K.Kosako  <sndgk393 AT ybb DOT ne DOT jp>
+ * Copyright (c) 2002-2016  K.Kosako  <sndgk393 AT ybb DOT ne DOT jp>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -661,6 +661,27 @@ onigenc_always_false_is_allowed_reverse_match(const UChar* s   ARG_UNUSED,
   return FALSE;
 }
 
+extern int
+onigenc_always_true_is_valid_mbc_string(const UChar* s   ARG_UNUSED,
+					const UChar* end ARG_UNUSED)
+{
+  return TRUE;
+}
+
+extern int
+onigenc_length_check_is_valid_mbc_string(OnigEncoding enc,
+					 const UChar* p, const UChar* end)
+{
+  while (p < end) {
+    p += enclen(enc, p);
+  }
+
+  if (p != end)
+    return FALSE;
+  else
+    return TRUE;
+}
+
 extern OnigCodePoint
 onigenc_mbn_mbc_to_code(OnigEncoding enc, const UChar* p, const UChar* end)
 {
diff --git a/src/regenc.h b/src/regenc.h
index 12e96ed..953765d 100644
--- a/src/regenc.h
+++ b/src/regenc.h
@@ -135,6 +135,8 @@ ONIG_EXTERN int onigenc_single_byte_code_to_mbc P_((OnigCodePoint code, UChar *b
 ONIG_EXTERN UChar* onigenc_single_byte_left_adjust_char_head P_((const UChar* start, const UChar* s));
 ONIG_EXTERN int onigenc_always_true_is_allowed_reverse_match P_((const UChar* s, const UChar* end));
 ONIG_EXTERN int onigenc_always_false_is_allowed_reverse_match P_((const UChar* s, const UChar* end));
+ONIG_EXTERN int onigenc_always_true_is_valid_mbc_string P_((const UChar* s, const UChar* end));
+ONIG_EXTERN int onigenc_length_check_is_valid_mbc_string P_((OnigEncoding enc, const UChar* s, const UChar* end));
 
 /* methods for multi byte encoding */
 ONIG_EXTERN OnigCodePoint onigenc_mbn_mbc_to_code P_((OnigEncoding enc, const UChar* p, const UChar* end));
diff --git a/src/regparse.c b/src/regparse.c
index dacc74f..5af1c8c 100644
--- a/src/regparse.c
+++ b/src/regparse.c
@@ -5303,19 +5303,6 @@ parse_regexp(Node** top, UChar** src, UChar* end, ScanEnv* env)
   return 0;
 }
 
-static int
-check_incomplete_multibyte_string(OnigEncoding enc, const UChar* p, const UChar* end)
-{
-  while (p < end) {
-    p += enclen(enc, p);
-  }
-
-  if (p != end)
-    return -1;
-  else
-    return 0;
-}
-
 extern int
 onig_parse_make_tree(Node** root, const UChar* pattern, const UChar* end,
 		     regex_t* reg, ScanEnv* env)
@@ -5338,8 +5325,8 @@ onig_parse_make_tree(Node** root, const UChar* pattern, const UChar* end,
 
   *root = NULL;
 
-  if (check_incomplete_multibyte_string(env->enc, pattern, end) != 0)
-    return ONIGERR_TOO_SHORT_MULTI_BYTE_STRING;
+  if (! ONIGENC_IS_VALID_MBC_STRING(env->enc, pattern, end))
+    return ONIGERR_INVALID_WIDE_CHAR_VALUE;
 
   p = (UChar* )pattern;
   r = parse_regexp(root, &p, (UChar* )end, env);
diff --git a/src/sjis.c b/src/sjis.c
index 84843ae..a607b3d 100644
--- a/src/sjis.c
+++ b/src/sjis.c
@@ -76,6 +76,12 @@ mbc_enc_len(const UChar* p)
   return EncLen_SJIS[*p];
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_SJIS, s, end);
+}
+
 static int
 code_to_mbclen(OnigCodePoint code)
 {
@@ -303,5 +309,6 @@ OnigEncodingType OnigEncodingSJIS = {
   left_adjust_char_head,
   is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/utf16_be.c b/src/utf16_be.c
index e93b42a..f220cca 100644
--- a/src/utf16_be.c
+++ b/src/utf16_be.c
@@ -54,6 +54,12 @@ utf16be_mbc_enc_len(const UChar* p)
   return EncLen_UTF16[*p];
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_UTF16_BE, s, end);
+}
+
 static int
 utf16be_is_mbc_newline(const UChar* p, const UChar* end)
 {
@@ -224,5 +230,6 @@ OnigEncodingType OnigEncodingUTF16_BE = {
   utf16be_left_adjust_char_head,
   onigenc_always_false_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/utf16_le.c b/src/utf16_le.c
index 2d9af52..4f0414e 100644
--- a/src/utf16_le.c
+++ b/src/utf16_le.c
@@ -60,6 +60,12 @@ utf16le_mbc_enc_len(const UChar* p)
   return EncLen_UTF16[*(p+1)];
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_UTF16_LE, s, end);
+}
+
 static int
 utf16le_is_mbc_newline(const UChar* p, const UChar* end)
 {
@@ -225,5 +231,6 @@ OnigEncodingType OnigEncodingUTF16_LE = {
   utf16le_left_adjust_char_head,
   onigenc_always_false_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/utf32_be.c b/src/utf32_be.c
index b8f64af..d0c7f39 100644
--- a/src/utf32_be.c
+++ b/src/utf32_be.c
@@ -35,6 +35,12 @@ utf32be_mbc_enc_len(const UChar* p ARG_UNUSED)
   return 4;
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_UTF32_BE, s, end);
+}
+
 static int
 utf32be_is_mbc_newline(const UChar* p, const UChar* end)
 {
@@ -183,5 +189,6 @@ OnigEncodingType OnigEncodingUTF32_BE = {
   utf32be_left_adjust_char_head,
   onigenc_always_false_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/utf32_le.c b/src/utf32_le.c
index a5a048e..33200d1 100644
--- a/src/utf32_le.c
+++ b/src/utf32_le.c
@@ -35,6 +35,12 @@ utf32le_mbc_enc_len(const UChar* p ARG_UNUSED)
   return 4;
 }
 
+static int
+is_valid_mbc_string(const UChar* s, const UChar* end)
+{
+  return onigenc_length_check_is_valid_mbc_string(ONIG_ENCODING_UTF32_LE, s, end);
+}
+
 static int
 utf32le_is_mbc_newline(const UChar* p, const UChar* end)
 {
@@ -183,5 +189,6 @@ OnigEncodingType OnigEncodingUTF32_LE = {
   utf32le_left_adjust_char_head,
   onigenc_always_false_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };
diff --git a/src/utf8.c b/src/utf8.c
index 38b13a5..90b7ff0 100644
--- a/src/utf8.c
+++ b/src/utf8.c
@@ -39,6 +39,7 @@
 #endif
 
 #define utf8_islead(c)     ((UChar )((c) & 0xc0) != 0x80)
+#define utf8_istail(c)     ((UChar )((c) & 0xc0) == 0x80)
 
 static const int EncLen_UTF8[] = {
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
@@ -65,6 +66,33 @@ mbc_enc_len(const UChar* p)
   return EncLen_UTF8[*p];
 }
 
+static int
+is_valid_mbc_string(const UChar* p, const UChar* end)
+{
+  int i, len;
+
+  while (p < end) {
+    if (! utf8_islead(*p))
+      return FALSE;
+
+    len = mbc_enc_len(p++);
+    if (len > 1) {
+      for (i = 1; i < len; i++) {
+	if (p == end)
+	  return FALSE;
+
+	if (! utf8_istail(*p++))
+	  return FALSE;
+      }
+    }
+  }
+
+  if (p != end)
+    return FALSE;
+  else
+    return TRUE;
+}
+
 static int
 is_mbc_newline(const UChar* p, const UChar* end)
 {
@@ -303,5 +331,6 @@ OnigEncodingType OnigEncodingUTF8 = {
   left_adjust_char_head,
   onigenc_always_true_is_allowed_reverse_match,
   NULL, /* init */
-  NULL  /* is_initialized */
+  NULL, /* is_initialized */
+  is_valid_mbc_string
 };