- int retlen = (int) m_conv->MB2WC(wbuf, m_lastBytes, 2); // returns -1 for failure
- if(retlen >= 0) // res == 0 could happen for '\0' char
- return wbuf[0];
+ switch ( m_conv->ToWChar(wbuf, WXSIZEOF(wbuf), m_lastBytes, inlen + 1) )
+ {
+ case 0:
+ // this is a bug in converter object as it should either fail
+ // or decode non-empty string to something non-empty
+ wxFAIL_MSG("ToWChar() can't return 0 for non-empty input");
+ break;
+
+ case wxCONV_FAILED:
+ // the buffer probably doesn't contain enough bytes to decode
+ // as a complete character, try with more bytes
+ break;
+
+ default:
+ // if we couldn't decode a single character during the last
+ // loop iteration we shouldn't be able to decode 2 or more of
+ // them with an extra single byte, something fishy is going on
+ wxFAIL_MSG("unexpected decoding result");
+ // fall through nevertheless and return at least something
+
+ case 1:
+ // we finally decoded a character
+ return wbuf[0];
+ }