Fix an out-of-boundary issue for wide string

core/src/fxcrt/fx_basic_wstring.cpp

Index: core/src/fxcrt/fx_basic_wstring.cpp
diff --git a/core/src/fxcrt/fx_basic_wstring.cpp b/core/src/fxcrt/fx_basic_wstring.cpp
index 192579fe547e1dda087542b83f4a1a4a59135203..36b0ad001ea5d3a789760ec5488d0e5b874c7146 100644
--- a/core/src/fxcrt/fx_basic_wstring.cpp
+++ b/core/src/fxcrt/fx_basic_wstring.cpp
@@ -401,12 +401,7 @@ CFX_WideString CFX_WideString::FromUTF8(const char* str, FX_STRSIZE len)
     if (!str) {

[palmer, 2014/07/12 00:54:39]

You could say:

    if (!str || 0 == len)

to avoid the (infinitesimal) cost of constructing and calling CFX_UTF8Decoder.

Then this function would match the behavior on line 413.

[Bo Xu, 2014/07/12 05:18:04]

Done.

         return CFX_WideString();
     }
-    if (len < 0) {
-        len = 0;
-        while (str[len]) {
-            len ++;
-        }
-    }
+
     CFX_UTF8Decoder decoder;
     for (FX_STRSIZE i = 0; i < len; i ++) {
         decoder.Input(str[i]);
@@ -418,12 +413,7 @@ CFX_WideString CFX_WideString::FromUTF16LE(const unsigned short* wstr, FX_STRSIZ
     if (!wstr || !wlen) {
         return CFX_WideString();
     }
-    if (wlen < 0) {
-        wlen = 0;
-        while (wstr[wlen]) {
-            wlen ++;
-        }
-    }
+
     CFX_WideString result;
     FX_WCHAR* buf = result.GetBuffer(wlen);
     for (int i = 0; i < wlen; i ++) {