Getting rid of more (FX_LPCWSTR) casts and fixing two bugs revealed by this.

core/include/fxcrt/fx_string.h

Index: core/include/fxcrt/fx_string.h
diff --git a/core/include/fxcrt/fx_string.h b/core/include/fxcrt/fx_string.h
index 26b04b70fad6f12c70e7ccf4dd7b9601d8c4872a..41bd0d3e7b902a7ec8479cde7435760d176ea419 100644
--- a/core/include/fxcrt/fx_string.h
+++ b/core/include/fxcrt/fx_string.h
@@ -597,7 +597,7 @@ private:
     }
 };
 typedef const CFX_WideStringC&	FX_WSTR;
-#define FX_WSTRC(wstr) CFX_WideStringC((FX_LPCWSTR)wstr, sizeof(wstr) / sizeof(FX_WCHAR) - 1)
+#define FX_WSTRC(wstr) CFX_WideStringC(wstr, sizeof(wstr) / sizeof(FX_WCHAR) - 1)
 struct CFX_StringDataW {
 
     long		m_nRefs;
@@ -640,9 +640,16 @@ public:
 
     static FX_STRSIZE       WStringLength(const unsigned short* str);
 
+    // Explicit conversion -- safer
+    FX_LPCWSTR c_str() const
+    {
+        return m_pData ? m_pData->m_String : L"";
+    }
+
+    // Implicit conversion -- potentially risky

[Tom Sepez, 2014/11/17 18:31:37]

Can we remove this and fix the places where it fails? Or was that in line for a
follow-on CL?

[brucedawson, 2014/11/17 18:41:55]

Follow-on CL would be better. Simply removing the conversion operator causes 357
errors (perhaps many more). The sanest way to fix them would be to add more
overrides to reduce the implicit conversion count -- not trivial.

     operator FX_LPCWSTR() const

[Tom Sepez, 2014/11/17 18:31:37]

Also, maybe we want to mark this cast operator as explicit to prevent it from
being applied without a cast?

[brucedawson, 2014/11/17 18:41:55]

That leads to just as many errors and would then encourage adding casts, which
have been shown to hide errors, so I'd prefer not to take that route.

     {
-        return m_pData ? m_pData->m_String : (FX_WCHAR*)L"";
+        return m_pData ? m_pData->m_String : L"";
     }
 
     void					Empty();
@@ -762,12 +769,12 @@ protected:
 };
 inline CFX_WideStringC::CFX_WideStringC(const CFX_WideString& src)
 {
-    m_Ptr = (FX_LPCWSTR)src;
+    m_Ptr = src.c_str();
     m_Length = src.GetLength();
 }
 inline CFX_WideStringC& CFX_WideStringC::operator = (const CFX_WideString& src)
 {
-    m_Ptr = (FX_LPCWSTR)src;
+    m_Ptr = src.c_str();
     m_Length = src.GetLength();
     return *this;
 }
@@ -841,6 +848,6 @@ inline CFX_ByteString	FX_UTF8Encode(FX_WSTR wsStr)
 }
 inline CFX_ByteString	FX_UTF8Encode(const CFX_WideString &wsStr)
 {
-    return FX_UTF8Encode((FX_LPCWSTR)wsStr, wsStr.GetLength());
+    return FX_UTF8Encode(wsStr.c_str(), wsStr.GetLength());
 }
 #endif