[ruby] * use static variable to avoid creating stirngs every time.

       * fix possible overflow.

1 files changed, 16 insertions, 14 deletions

diff --git a/Lib/ruby/rubywstrings.swg b/Lib/ruby/rubywstrings.swg
index 043f213bc..54724b268 100644
--- a/Lib/ruby/rubywstrings.swg
+++ b/Lib/ruby/rubywstrings.swg
@@ -8,23 +8,23 @@
 SWIGINTERN int
 SWIG_AsWCharPtrAndSize(VALUE obj, wchar_t **cptr, size_t *psize, int *alloc)
 {
+  static rb_encoding* wstr_enc = rb_to_encoding(rb_str_new_cstr( SWIG_RUBY_WSTRING_ENCODING ));
 
   if (TYPE(obj) == T_STRING) {
-    VALUE tmp = rb_str_conv_enc(obj, rb_enc_get(obj),
-                                rb_to_encoding(rb_str_new_cstr( SWIG_RUBY_WSTRING_ENCODING )) );
-    wchar_t* cstr = (wchar_t*) StringValuePtr(tmp);
-    size_t   size = RSTRING_LEN(tmp) / sizeof(wchar_t) + 1;
+    VALUE rstr = rb_str_conv_enc(obj, rb_enc_get(obj), wstr_enc);
+    wchar_t* cstr = (wchar_t*) StringValuePtr(rstr);
+    size_t   size = RSTRING_LEN(rstr) / sizeof(wchar_t) + 1;
 
-    if( RSTRING_LEN(tmp) % sizeof(wchar_t) != 0 ) {
+    if ( RSTRING_LEN(rstr) % sizeof(wchar_t) != 0 ) {
         rb_raise(rb_eRuntimeError,
                  "The length of the byte sequence of converted string is not a multiplier of sizeof(wchar_t). Invalid byte sequence is given. Or invalid SWIG_RUBY_WSTRING_ENCODING is given when compiling this binding.");
     }
     if (cptr && alloc)  {
       *alloc = SWIG_NEWOBJ;
       *cptr = %new_array(size, wchar_t);
-      memmove(*cptr, cstr, RSTRING_LEN(tmp));
+      memmove(*cptr, cstr, RSTRING_LEN(rstr));
     }
-    if(psize) *psize = size;
+    if (psize) *psize = size;
 
     return SWIG_OK;
   } else {
@@ -37,16 +37,18 @@ SWIG_AsWCharPtrAndSize(VALUE obj, wchar_t **cptr, size_t *psize, int *alloc)
 SWIGINTERNINLINE VALUE 
 SWIG_FromWCharPtrAndSize(const wchar_t * carray, size_t size)
 {
-  if (carray && size <= LONG_MAX) {
-    VALUE ret = rb_str_new( (const char*)carray, %numeric_cast(size*sizeof(wchar_t),long) );
-    rb_encoding* new_enc = rb_default_internal_encoding();
+  static rb_encoding* wstr_enc = rb_to_encoding(rb_str_new_cstr( SWIG_RUBY_WSTRING_ENCODING ));
+  static rb_encoding* rb_enc = rb_to_encoding(rb_str_new_cstr( SWIG_RUBY_INTERNAL_ENCODING ));
 
-    rb_enc_associate(ret, rb_to_encoding(rb_str_new_cstr( SWIG_RUBY_WSTRING_ENCODING )) );
+  if (carray && size <= LONG_MAX/sizeof(wchar_t)) {
+    VALUE rstr = rb_str_new( (const char*)carray, %numeric_cast(size*sizeof(wchar_t),long) );
+    rb_encoding* new_enc = rb_default_internal_encoding();
 
-    if( !new_enc ) {
-      new_enc = rb_to_encoding(rb_str_new_cstr( SWIG_RUBY_INTERNAL_ENCODING ));
+    rb_enc_associate(rstr, wstr_enc);
+    if ( !new_enc ) {
+      new_enc = rb_enc;
     }
-    return rb_str_conv_enc(ret, rb_enc_get(ret), new_enc);
+    return rb_str_conv_enc(rstr, wstr_enc, new_enc);
   } else {
     return Qnil;
   }