Allow cp932 characters to be stored in a SJIS column

1 files changed, 35 insertions, 1 deletions

diff --git a/strings/ctype-sjis.c b/strings/ctype-sjis.c
index 55ff8ac28fe..4176ff2e538 100644
--- a/strings/ctype-sjis.c
+++ b/strings/ctype-sjis.c
@@ -4563,6 +4563,40 @@ uint my_numcells_sjis(CHARSET_INFO *cs __attribute__((unused)),
   return clen;
 }
 
+/*
+  Returns a well formed length of a SJIS string.
+  CP932 additional characters are also accepted.
+*/
+static
+uint my_well_formed_len_sjis(CHARSET_INFO *cs __attribute__((unused)),
+                             const char *b, const char *e, uint pos)
+{
+  const char *b0= b;
+  while (pos && b < e)
+  {
+    /*
+      Cast to int8 for extra safety.
+      "char" can be unsigned by default
+      on some platforms.
+    */
+    if (((int8)b[0]) >= 0)
+    {
+      /* Single byte character */
+      b+= 1;
+    }
+    else  if (issjishead((uchar)*b) && (e-b)>1 && issjistail((uchar)b[1]))
+    {
+      /* Double byte character */
+      b+= 2;
+    }
+    else
+    {
+      /* Wrong byte sequence */
+      break;
+    }
+  }
+  return b - b0;
+}
 
 
 static MY_COLLATION_HANDLER my_collation_ci_handler =
@@ -4586,7 +4620,7 @@ static MY_CHARSET_HANDLER my_charset_handler=
   mbcharlen_sjis,
   my_numchars_mb,
   my_charpos_mb,
-  my_well_formed_len_mb,
+  my_well_formed_len_sjis,
   my_lengthsp_8bit,
   my_numcells_sjis,
   my_mb_wc_sjis,	/* mb_wc */