]> git.saurik.com Git - wxWidgets.git/blobdiff - src/common/strconv.cpp
don't crash when loading images with verbose==false (patch 1449823)
[wxWidgets.git] / src / common / strconv.cpp
index 76282821dbe1bd887e5d727add6bee9f62c2d382..e50eddf3f93b5f796aa7bc6185b2a623229a52e4 100644 (file)
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////////
-// Name:        strconv.cpp
+// Name:        src/common/strconv.cpp
 // Purpose:     Unicode conversion classes
 // Author:      Ove Kaaven, Robert Roebling, Vadim Zeitlin, Vaclav Slavik,
 //              Ryan Norton, Fredrik Roubert (UTF7)
 // headers
 // ----------------------------------------------------------------------------
 
-#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
-  #pragma implementation "strconv.h"
-#endif
-
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
 
 #if wxUSE_WCHAR_T
 
-#ifdef __WXMSW__
-    #include "wx/msw/private.h"
-#endif
-
 #ifdef __WINDOWS__
+    #include "wx/msw/private.h"
     #include "wx/msw/missing.h"
 #endif
 
     #define wxHAVE_WIN32_MB2WC
 #endif // __WIN32__ but !__WXMICROWIN__
 
-// ----------------------------------------------------------------------------
-// headers
-// ----------------------------------------------------------------------------
-
 #ifdef __SALFORDC__
     #include <clib.h>
 #endif
 #include "wx/utils.h"
 
 #ifdef __WXMAC__
+#ifndef __DARWIN__
 #include <ATSUnicode.h>
 #include <TextCommon.h>
 #include <TextEncodingConverter.h>
+#endif
 
 #include  "wx/mac/private.h"  // includes mac headers
 #endif
-// ----------------------------------------------------------------------------
-// macros
-// ----------------------------------------------------------------------------
 
-#define BSWAP_UCS4(str, len) { unsigned _c; for (_c=0; _c<len; _c++) str[_c]=wxUINT32_SWAP_ALWAYS(str[_c]); }
-#define BSWAP_UTF16(str, len) { unsigned _c; for (_c=0; _c<len; _c++) str[_c]=wxUINT16_SWAP_ALWAYS(str[_c]); }
+#define TRACE_STRCONV _T("strconv")
 
-#if SIZEOF_WCHAR_T == 4
-    #define WC_NAME         "UCS4"
-    #define WC_BSWAP         BSWAP_UCS4
-    #ifdef WORDS_BIGENDIAN
-      #define WC_NAME_BEST  "UCS-4BE"
-    #else
-      #define WC_NAME_BEST  "UCS-4LE"
-    #endif
-#elif SIZEOF_WCHAR_T == 2
-    #define WC_NAME         "UTF16"
-    #define WC_BSWAP         BSWAP_UTF16
+#if SIZEOF_WCHAR_T == 2
     #define WC_UTF16
-    #ifdef WORDS_BIGENDIAN
-      #define WC_NAME_BEST  "UTF-16BE"
-    #else
-      #define WC_NAME_BEST  "UTF-16LE"
-    #endif
-#else // sizeof(wchar_t) != 2 nor 4
-    // does this ever happen?
-    #error "Unknown sizeof(wchar_t): please report this to wx-dev@lists.wxwindows.org"
 #endif
 
 // ============================================================================
@@ -152,7 +121,7 @@ static size_t decode_utf16(const wxUint16* input, wxUint32& output)
         output = *input;
         return 1;
     }
-    else if ((input[1]<0xdc00) || (input[1]>=0xdfff))
+    else if ((input[1]<0xdc00) || (input[1]>0xdfff))
     {
         output = *input;
         return (size_t)-1;
@@ -218,129 +187,161 @@ const wxCharBuffer wxMBConv::cWC2MB(const wchar_t *pwz) const
     return buf;
 }
 
-const wxWCharBuffer wxMBConv::cMB2WC(const char *szString, size_t nStringLen, size_t* pOutSize) const
+const wxWCharBuffer
+wxMBConv::cMB2WC(const char *in, size_t inLen, size_t *outLen) const
 {
-    wxASSERT(pOutSize != NULL);
+    // the currently accumulated wide characters
+    wxWCharBuffer wbuf;
 
-    const char* szEnd = szString + nStringLen + 1;
-    const char* szPos = szString;
-    const char* szStart = szPos;
+    // the current length of wbuf
+    size_t lenBuf = 0;
 
-    size_t nActualLength = 0;
-    size_t nCurrentSize = nStringLen; //try normal size first (should never resize?)
+    // we need to know the representation of L'\0' for this conversion
+    size_t nulLen;
+    const char * const nul = GetMBNul(&nulLen);
+    if ( nulLen == (size_t)-1 || nulLen == 0 )
+        return wxWCharBuffer();
 
-    wxWCharBuffer theBuffer(nCurrentSize);
+    // make a copy of the input string unless it is already properly
+    // NUL-terminated
+    wxCharBuffer bufTmp;
 
-    //Convert the string until the length() is reached, continuing the
-    //loop every time a null character is reached
-    while(szPos != szEnd)
+    // now we can compute the input size if we were not given it: notice that
+    // in this case the string must be properly NUL-terminated, of course, as
+    // otherwise we have no way of knowing how long it is
+    if ( inLen == (size_t)-1 )
     {
-        wxASSERT(szPos < szEnd); //something is _really_ screwed up if this rings true
-
-        //Get the length of the current (sub)string
-        size_t nLen = MB2WC(NULL, szPos, 0);
+        // not the most efficient algorithm but it shouldn't matter as normally
+        // there are not many NULs in the string and so normally memcmp()
+        // should stop on the first character
+        const char *p = in;
+        while ( memcmp(p, nul, nulLen) != 0 )
+            p++;
 
-        //Invalid conversion?
-        if( nLen == (size_t)-1 )
+        inLen = p - in + nulLen;
+    }
+    else // we already have the size
+    {
+        // check if it's not already NUL-terminated too to avoid the copy
+        if ( inLen < nulLen || memcmp(in + inLen - nulLen, nul, nulLen) != 0 )
         {
-            *pOutSize = 0;
-            theBuffer.data()[0u] = wxT('\0');
-            return theBuffer;
+            // make a copy in order to properly NUL-terminate the string
+            bufTmp = wxCharBuffer(inLen + nulLen - 1 /* 1 will be added */);
+            memcpy(bufTmp.data(), in, inLen);
+            memcpy(bufTmp.data() + inLen, nul, nulLen);
         }
+    }
 
+    if ( bufTmp )
+        in = bufTmp;
 
-        //Increase the actual length (+1 for current null character)
-        nActualLength += nLen + 1;
-
-        //if buffer too big, realloc the buffer
-        if (nActualLength > (nCurrentSize+1))
+    for ( const char * const inEnd = in + inLen;; )
+    {
+        // try to convert the current chunk if anything left
+        size_t lenChunk = in < inEnd ? MB2WC(NULL, in, 0) : 0;
+        if ( lenChunk == 0 )
         {
-            wxWCharBuffer theNewBuffer(nCurrentSize << 1);
-            memcpy(theNewBuffer.data(), theBuffer.data(), nCurrentSize * sizeof(wchar_t));
-            theBuffer = theNewBuffer;
-            nCurrentSize <<= 1;
-        }
+            // nothing left in the input string, conversion succeeded
+            if ( outLen )
+            {
+                // we shouldn't include the last NUL in the result length
+                *outLen = lenBuf ? lenBuf - 1 : 0;
+            }
 
-        //Convert the current (sub)string
-        if ( MB2WC(&theBuffer.data()[szPos - szStart], szPos, nLen + 1) == (size_t)-1 )
-        {
-            *pOutSize = 0;
-            theBuffer.data()[0u] = wxT('\0');
-            return theBuffer;
+            return wbuf;
         }
 
-        //Increment to next (sub)string
-        //Note that we have to use strlen here instead of nLen
-        //here because XX2XX gives us the size of the output buffer,
-        //not neccessarly the length of the string
-        szPos += strlen(szPos) + 1;
+        if ( lenChunk == (size_t)-1 )
+            break;
+
+        const size_t lenBufNew = lenBuf + lenChunk;
+        if ( !wbuf.extend(lenBufNew) )
+            break;
+
+        lenChunk = MB2WC(wbuf.data() + lenBuf, in, lenChunk + 1 /* for NUL */);
+        if ( lenChunk == (size_t)-1 )
+            break;
+
+        // +! for the embedded NUL (if something follows)
+        lenBuf = lenBufNew + 1;
+
+        // advance the input pointer past the end of this chunk
+        while ( memcmp(in, nul, nulLen) != 0 )
+            in++;
+
+        in += nulLen; // skipping over its terminator as well
     }
 
-    //success - return actual length and the buffer
-    *pOutSize = nActualLength;
-    return theBuffer;  
+    // conversion failed
+    if ( outLen )
+        *outLen = 0;
+
+    return wxWCharBuffer();
 }
 
-const wxCharBuffer wxMBConv::cWC2MB(const wchar_t *szString, size_t nStringLen, size_t* pOutSize) const
+const wxCharBuffer
+wxMBConv::cWC2MB(const wchar_t *in, size_t inLen, size_t *outLen) const
 {
-    wxASSERT(pOutSize != NULL);
-
-    const wchar_t* szEnd = szString + nStringLen + 1;
-    const wchar_t* szPos = szString;
-    const wchar_t* szStart = szPos;
+    // the currently accumulated multibyte characters
+    wxCharBuffer buf;
 
-    size_t nActualLength = 0;
-    size_t nCurrentSize = nStringLen << 2; //try * 4 first
+    // the current length of buf
+    size_t lenBuf = 0;
 
-    wxCharBuffer theBuffer(nCurrentSize);
-
-    //Convert the string until the length() is reached, continuing the
-    //loop every time a null character is reached
-    while(szPos != szEnd)
+    // make a copy of the input string unless it is already properly
+    // NUL-terminated
+    //
+    // if we don't know its length we have no choice but to assume that it is,
+    // indeed, properly terminated
+    wxWCharBuffer bufTmp;
+    if ( inLen == (size_t)-1 )
     {
-        wxASSERT(szPos < szEnd); //something is _really_ screwed up if this rings true
+        inLen = wxWcslen(in) + 1;
+    }
+    else if ( inLen != 0 && in[inLen - 1] != L'\0' )
+    {
+        // make a copy in order to properly NUL-terminate the string
+        bufTmp = wxWCharBuffer(inLen);
+        memcpy(bufTmp.data(), in, inLen*sizeof(wchar_t));
+    }
 
-        //Get the length of the current (sub)string
-        size_t nLen = WC2MB(NULL, szPos, 0);
+    if ( bufTmp )
+        in = bufTmp;
 
-        //Invalid conversion?
-        if( nLen == (size_t)-1 )
+    for ( const wchar_t * const inEnd = in + inLen;; )
+    {
+        // try to convert the current chunk, if anything left
+        size_t lenChunk = in < inEnd ? WC2MB(NULL, in, 0) : 0;
+        if ( lenChunk == 0 )
         {
-            *pOutSize = 0;
-            theBuffer.data()[0u] = wxT('\0');
-            return theBuffer;
-        }
+            // nothing left in the input string, conversion succeeded
+            if ( outLen )
+                *outLen = lenBuf ? lenBuf - 1 : lenBuf;
 
-        //Increase the actual length (+1 for current null character)
-        nActualLength += nLen + 1;
-        
-        //if buffer too big, realloc the buffer
-        if (nActualLength > (nCurrentSize+1))
-        {
-            wxCharBuffer theNewBuffer(nCurrentSize << 1);
-            memcpy(theNewBuffer.data(), theBuffer.data(), nCurrentSize);
-            theBuffer = theNewBuffer;
-            nCurrentSize <<= 1;
+            return buf;
         }
 
-        //Convert the current (sub)string
-        if(WC2MB(&theBuffer.data()[szPos - szStart], szPos, nLen + 1) == (size_t)-1 )
-        {
-            *pOutSize = 0;
-            theBuffer.data()[0u] = wxT('\0');
-            return theBuffer;
-        }
+        if ( lenChunk == (size_t)-1 )
+            break;
 
-        //Increment to next (sub)string
-        //Note that we have to use wxWcslen here instead of nLen
-        //here because XX2XX gives us the size of the output buffer,
-        //not neccessarly the length of the string
-        szPos += wxWcslen(szPos) + 1;
+        const size_t lenBufNew = lenBuf + lenChunk;
+        if ( !buf.extend(lenBufNew) )
+            break;
+
+        lenChunk = WC2MB(buf.data() + lenBuf, in, lenChunk + 1 /* for NUL */);
+        if ( lenChunk == (size_t)-1 )
+            break;
+
+        // chunk successfully converted, go to the next one
+        in += wxWcslen(in) + 1 /* skip NUL too */;
+        lenBuf = lenBufNew + 1;
     }
 
-    //success - return actual length and the buffer
-    *pOutSize = nActualLength;
-    return theBuffer;  
+    // conversion failed
+    if ( outLen )
+        *outLen = 0;
+
+    return wxCharBuffer();
 }
 
 // ----------------------------------------------------------------------------
@@ -356,8 +357,26 @@ size_t wxMBConvLibc::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 {
     return wxWC2MB(buf, psz, n);
 }
+
 // ----------------------------------------------------------------------------
-// UTF-7 
+// wxConvBrokenFileNames
+// ----------------------------------------------------------------------------
+
+#ifdef __UNIX__
+
+wxConvBrokenFileNames::wxConvBrokenFileNames(const wxChar *charset)
+{
+    if ( !charset || wxStricmp(charset, _T("UTF-8")) == 0
+                  || wxStricmp(charset, _T("UTF8")) == 0  )
+        m_conv = new wxMBConvUTF8(wxMBConvUTF8::MAP_INVALID_UTF8_TO_OCTAL);
+    else
+        m_conv = new wxCSConv(charset);
+}
+
+#endif // __UNIX__
+
+// ----------------------------------------------------------------------------
+// UTF-7
 // ----------------------------------------------------------------------------
 
 // Implementation (C) 2004 Fredrik Roubert
@@ -405,7 +424,7 @@ size_t wxMBConvUTF7::MB2WC(wchar_t *buf, const char *psz, size_t n) const
 {
     size_t len = 0;
 
-    while (*psz && ((!buf) || (len < n)))
+    while ( *psz && (!buf || (len < n)) )
     {
         unsigned char cc = *psz++;
         if (cc != '+')
@@ -423,20 +442,19 @@ size_t wxMBConvUTF7::MB2WC(wchar_t *buf, const char *psz, size_t n) const
             len++;
             psz++;
         }
-        else
+        else // start of BASE64 encoded string
         {
-            // BASE64 encoded string
-            bool lsb;
-            unsigned char c;
+            bool lsb, ok;
             unsigned int d, l;
-            for (lsb = false, d = 0, l = 0;
-                (cc = utf7unb64[(unsigned char)*psz]) != 0xff; psz++)
+            for ( ok = lsb = false, d = 0, l = 0;
+                  (cc = utf7unb64[(unsigned char)*psz]) != 0xff;
+                  psz++ )
             {
                 d <<= 6;
                 d += cc;
                 for (l += 6; l >= 8; lsb = !lsb)
                 {
-                    c = (unsigned char)((d >> (l -= 8)) % 256);
+                    unsigned char c = (unsigned char)((d >> (l -= 8)) % 256);
                     if (lsb)
                     {
                         if (buf)
@@ -444,16 +462,29 @@ size_t wxMBConvUTF7::MB2WC(wchar_t *buf, const char *psz, size_t n) const
                         len ++;
                     }
                     else
+                    {
                         if (buf)
                             *buf = (wchar_t)(c << 8);
+                    }
+
+                    ok = true;
                 }
             }
+
+            if ( !ok )
+            {
+                // in valid UTF7 we should have valid characters after '+'
+                return (size_t)-1;
+            }
+
             if (*psz == '-')
                 psz++;
         }
     }
-    if (buf && (len < n))
-        *buf = 0;
+
+    if ( buf && (len < n) )
+        *buf = '\0';
+
     return len;
 }
 
@@ -494,8 +525,6 @@ static const unsigned char utf7encode[128] =
 
 size_t wxMBConvUTF7::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 {
-
-
     size_t len = 0;
 
     while (*psz && ((!buf) || (len < n)))
@@ -510,7 +539,7 @@ size_t wxMBConvUTF7::WC2MB(char *buf, const wchar_t *psz, size_t n) const
         }
 #ifndef WC_UTF16
         else if (((wxUint32)cc) > 0xffff)
-           {
+        {
             // no surrogate pair generation (yet?)
             return (size_t)-1;
         }
@@ -524,7 +553,7 @@ size_t wxMBConvUTF7::WC2MB(char *buf, const wchar_t *psz, size_t n) const
             {
                 // BASE64 encode string
                 unsigned int lsb, d, l;
-                for (d = 0, l = 0;; psz++)
+                for (d = 0, l = 0; /*nothing*/; psz++)
                 {
                     for (lsb = 0; lsb < 2; lsb ++)
                     {
@@ -567,12 +596,19 @@ size_t wxMBConvUTF7::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 static wxUint32 utf8_max[]=
     { 0x7f, 0x7ff, 0xffff, 0x1fffff, 0x3ffffff, 0x7fffffff, 0xffffffff };
 
+// boundaries of the private use area we use to (temporarily) remap invalid
+// characters invalid in a UTF-8 encoded string
+const wxUint32 wxUnicodePUA = 0x100000;
+const wxUint32 wxUnicodePUAEnd = wxUnicodePUA + 256;
+
 size_t wxMBConvUTF8::MB2WC(wchar_t *buf, const char *psz, size_t n) const
 {
     size_t len = 0;
 
     while (*psz && ((!buf) || (len < n)))
     {
+        const char *opsz = psz;
+        bool invalid = false;
         unsigned char cc = *psz++, fc = cc;
         unsigned cnt;
         for (cnt = 0; fc & 0x80; cnt++)
@@ -583,6 +619,15 @@ size_t wxMBConvUTF8::MB2WC(wchar_t *buf, const char *psz, size_t n) const
             if (buf)
                 *buf++ = cc;
             len++;
+
+            // escape the escape character for octal escapes
+            if ((m_options & MAP_INVALID_UTF8_TO_OCTAL)
+                    && cc == '\\' && (!buf || len < n))
+            {
+                if (buf)
+                    *buf++ = cc;
+                len++;
+            }
         }
         else
         {
@@ -590,7 +635,7 @@ size_t wxMBConvUTF8::MB2WC(wchar_t *buf, const char *psz, size_t n) const
             if (!cnt)
             {
                 // invalid UTF-8 sequence
-                return (size_t)-1;
+                invalid = true;
             }
             else
             {
@@ -598,32 +643,93 @@ size_t wxMBConvUTF8::MB2WC(wchar_t *buf, const char *psz, size_t n) const
                 wxUint32 res = cc & (0x3f >> cnt);
                 while (cnt--)
                 {
-                    cc = *psz++;
+                    cc = *psz;
                     if ((cc & 0xC0) != 0x80)
                     {
                         // invalid UTF-8 sequence
-                        return (size_t)-1;
+                        invalid = true;
+                        break;
                     }
+                    psz++;
                     res = (res << 6) | (cc & 0x3f);
                 }
-                if (res <= utf8_max[ocnt])
+                if (invalid || res <= utf8_max[ocnt])
                 {
                     // illegal UTF-8 encoding
-                    return (size_t)-1;
+                    invalid = true;
+                }
+                else if ((m_options & MAP_INVALID_UTF8_TO_PUA) &&
+                        res >= wxUnicodePUA && res < wxUnicodePUAEnd)
+                {
+                    // if one of our PUA characters turns up externally
+                    // it must also be treated as an illegal sequence
+                    // (a bit like you have to escape an escape character)
+                    invalid = true;
                 }
+                else
+                {
 #ifdef WC_UTF16
-                // cast is ok because wchar_t == wxUuint16 if WC_UTF16
-                size_t pa = encode_utf16(res, (wxUint16 *)buf);
-                if (pa == (size_t)-1)
-                  return (size_t)-1;
-                if (buf)
-                    buf += pa;
-                len += pa;
+                    // cast is ok because wchar_t == wxUuint16 if WC_UTF16
+                    size_t pa = encode_utf16(res, (wxUint16 *)buf);
+                    if (pa == (size_t)-1)
+                    {
+                        invalid = true;
+                    }
+                    else
+                    {
+                        if (buf)
+                            buf += pa;
+                        len += pa;
+                    }
 #else // !WC_UTF16
-                if (buf)
-                    *buf++ = res;
-                len++;
+                    if (buf)
+                        *buf++ = (wchar_t)res;
+                    len++;
 #endif // WC_UTF16/!WC_UTF16
+                }
+            }
+            if (invalid)
+            {
+                if (m_options & MAP_INVALID_UTF8_TO_PUA)
+                {
+                    while (opsz < psz && (!buf || len < n))
+                    {
+#ifdef WC_UTF16
+                        // cast is ok because wchar_t == wxUuint16 if WC_UTF16
+                        size_t pa = encode_utf16((unsigned char)*opsz + wxUnicodePUA, (wxUint16 *)buf);
+                        wxASSERT(pa != (size_t)-1);
+                        if (buf)
+                            buf += pa;
+                        opsz++;
+                        len += pa;
+#else
+                        if (buf)
+                            *buf++ = (wchar_t)(wxUnicodePUA + (unsigned char)*opsz);
+                        opsz++;
+                        len++;
+#endif
+                    }
+                }
+                else if (m_options & MAP_INVALID_UTF8_TO_OCTAL)
+                {
+                    while (opsz < psz && (!buf || len < n))
+                    {
+                        if ( buf && len + 3 < n )
+                        {
+                            unsigned char on = *opsz;
+                            *buf++ = L'\\';
+                            *buf++ = (wchar_t)( L'0' + on / 0100 );
+                            *buf++ = (wchar_t)( L'0' + (on % 0100) / 010 );
+                            *buf++ = (wchar_t)( L'0' + on % 010 );
+                        }
+                        opsz++;
+                        len += 4;
+                    }
+                }
+                else // MAP_INVALID_UTF8_NOT
+                {
+                    return (size_t)-1;
+                }
             }
         }
     }
@@ -632,6 +738,11 @@ size_t wxMBConvUTF8::MB2WC(wchar_t *buf, const char *psz, size_t n) const
     return len;
 }
 
+static inline bool isoctal(wchar_t wch)
+{
+    return L'0' <= wch && wch <= L'7';
+}
+
 size_t wxMBConvUTF8::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 {
     size_t len = 0;
@@ -646,36 +757,67 @@ size_t wxMBConvUTF8::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 #else
         cc=(*psz++) & 0x7fffffff;
 #endif
-        unsigned cnt;
-        for (cnt = 0; cc > utf8_max[cnt]; cnt++) {}
-        if (!cnt)
+
+        if ( (m_options & MAP_INVALID_UTF8_TO_PUA)
+                && cc >= wxUnicodePUA && cc < wxUnicodePUAEnd )
         {
-            // plain ASCII char
             if (buf)
-                *buf++ = (char) cc;
+                *buf++ = (char)(cc - wxUnicodePUA);
             len++;
         }
+        else if ( (m_options & MAP_INVALID_UTF8_TO_OCTAL)
+                    && cc == L'\\' && psz[0] == L'\\' )
+        {
+            if (buf)
+                *buf++ = (char)cc;
+            psz++;
+            len++;
+        }
+        else if ( (m_options & MAP_INVALID_UTF8_TO_OCTAL) &&
+                    cc == L'\\' &&
+                        isoctal(psz[0]) && isoctal(psz[1]) && isoctal(psz[2]) )
+        {
+            if (buf)
+            {
+                *buf++ = (char) ((psz[0] - L'0')*0100 +
+                                 (psz[1] - L'0')*010 +
+                                 (psz[2] - L'0'));
+            }
 
+            psz += 3;
+            len++;
+        }
         else
         {
-            len += cnt + 1;
-            if (buf)
+            unsigned cnt;
+            for (cnt = 0; cc > utf8_max[cnt]; cnt++) {}
+            if (!cnt)
             {
-                *buf++ = (char) ((-128 >> cnt) | ((cc >> (cnt * 6)) & (0x3f >> cnt)));
-                while (cnt--)
-                    *buf++ = (char) (0x80 | ((cc >> (cnt * 6)) & 0x3f));
+                // plain ASCII char
+                if (buf)
+                    *buf++ = (char) cc;
+                len++;
+            }
+
+            else
+            {
+                len += cnt + 1;
+                if (buf)
+                {
+                    *buf++ = (char) ((-128 >> cnt) | ((cc >> (cnt * 6)) & (0x3f >> cnt)));
+                    while (cnt--)
+                        *buf++ = (char) (0x80 | ((cc >> (cnt * 6)) & 0x3f));
+                }
             }
         }
     }
 
-    if (buf && (len<n)) *buf = 0;
+    if (buf && (len<n))
+        *buf = 0;
 
     return len;
 }
 
-
-
-
 // ----------------------------------------------------------------------------
 // UTF-16
 // ----------------------------------------------------------------------------
@@ -734,20 +876,24 @@ size_t wxMBConvUTF16straight::WC2MB(char *buf, const wchar_t *psz, size_t n) con
 // swap 16bit MB to 16bit String
 size_t wxMBConvUTF16swap::MB2WC(wchar_t *buf, const char *psz, size_t n) const
 {
-    size_t len=0;
+    size_t len = 0;
 
-    while (*(wxUint16*)psz && (!buf || len < n))
+    // UTF16 string must be terminated by 2 NULs as single NULs may occur
+    // inside the string
+    while ( (psz[0] || psz[1]) && (!buf || len < n) )
     {
-        if (buf)
+        if ( buf )
         {
             ((char *)buf)[0] = psz[1];
             ((char *)buf)[1] = psz[0];
             buf++;
         }
         len++;
-        psz += sizeof(wxUint16);
+        psz += 2;
     }
-    if (buf && len<n)   *buf=0;
+
+    if ( buf && len < n )
+        *buf = L'\0';
 
     return len;
 }
@@ -756,19 +902,21 @@ size_t wxMBConvUTF16swap::MB2WC(wchar_t *buf, const char *psz, size_t n) const
 // swap 16bit MB to 16bit String
 size_t wxMBConvUTF16swap::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 {
-    size_t len=0;
+    size_t len = 0;
 
-    while (*psz && (!buf || len < n))
+    while ( *psz && (!buf || len < n) )
     {
-        if (buf)
+        if ( buf )
         {
             *buf++ = ((char*)psz)[1];
             *buf++ = ((char*)psz)[0];
         }
-        len += sizeof(wxUint16);
+        len += 2;
         psz++;
     }
-    if (buf && len<=n-sizeof(wxUint16))   *(wxUint16*)buf=0;
+
+    if ( buf && len < n )
+        *buf = '\0';
 
     return len;
 }
@@ -790,7 +938,7 @@ size_t wxMBConvUTF16straight::MB2WC(wchar_t *buf, const char *psz, size_t n) con
             return pa;
 
         if (buf)
-            *buf++ = cc;
+            *buf++ = (wchar_t)cc;
         len++;
         psz += pa * sizeof(wxUint16);
     }
@@ -850,7 +998,7 @@ size_t wxMBConvUTF16swap::MB2WC(wchar_t *buf, const char *psz, size_t n) const
             return pa;
 
         if (buf)
-            *buf++ = cc;
+            *buf++ = (wchar_t)cc;
 
         len++;
         psz += pa * sizeof(wxUint16);
@@ -1051,7 +1199,7 @@ size_t wxMBConvUTF32straight::MB2WC(wchar_t *buf, const char *psz, size_t n) con
     while (*(wxUint32*)psz && (!buf || len < n))
     {
         if (buf)
-            *buf++ = *(wxUint32*)psz;
+            *buf++ = (wchar_t)(*(wxUint32*)psz);
         len++;
         psz += sizeof(wxUint32);
     }
@@ -1164,6 +1312,19 @@ size_t wxMBConvUTF32swap::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 
 #define ICONV_CHAR_CAST(x)  ((ICONV_CONST char **)(x))
 
+#define ICONV_T_INVALID ((iconv_t)-1)
+
+#if SIZEOF_WCHAR_T == 4
+    #define WC_BSWAP    wxUINT32_SWAP_ALWAYS
+    #define WC_ENC      wxFONTENCODING_UTF32
+#elif SIZEOF_WCHAR_T == 2
+    #define WC_BSWAP    wxUINT16_SWAP_ALWAYS
+    #define WC_ENC      wxFONTENCODING_UTF16
+#else // sizeof(wchar_t) != 2 nor 4
+    // does this ever happen?
+    #error "Unknown sizeof(wchar_t): please report this to wx-dev@lists.wxwindows.org"
+#endif
+
 // ----------------------------------------------------------------------------
 // wxMBConv_iconv: encapsulates an iconv character set
 // ----------------------------------------------------------------------------
@@ -1178,7 +1339,7 @@ public:
     virtual size_t WC2MB(char *buf, const wchar_t *psz, size_t n) const;
 
     bool IsOk() const
-        { return (m2w != (iconv_t)-1) && (w2m != (iconv_t)-1); }
+        { return (m2w != ICONV_T_INVALID) && (w2m != ICONV_T_INVALID); }
 
 protected:
     // the iconv handlers used to translate from multibyte to wide char and in
@@ -1191,110 +1352,157 @@ protected:
 #endif
 
 private:
+    virtual const char *GetMBNul(size_t *nulLen) const;
+
     // the name (for iconv_open()) of a wide char charset -- if none is
     // available on this machine, it will remain NULL
-    static const char *ms_wcCharsetName;
+    static wxString ms_wcCharsetName;
 
     // true if the wide char encoding we use (i.e. ms_wcCharsetName) has
     // different endian-ness than the native one
     static bool ms_wcNeedsSwap;
+
+    // NUL representation
+    size_t m_nulLen;
+    char m_nulBuf[8];
 };
 
-const char *wxMBConv_iconv::ms_wcCharsetName = NULL;
+// make the constructor available for unit testing
+WXDLLIMPEXP_BASE wxMBConv* new_wxMBConv_iconv( const wxChar* name )
+{
+    wxMBConv_iconv* result = new wxMBConv_iconv( name );
+    if ( !result->IsOk() )
+    {
+        delete result;
+        return 0;
+    }
+    return result;
+}
+
+wxString wxMBConv_iconv::ms_wcCharsetName;
 bool wxMBConv_iconv::ms_wcNeedsSwap = false;
 
 wxMBConv_iconv::wxMBConv_iconv(const wxChar *name)
 {
-    // Do it the hard way
-    char cname[100];
-    for (size_t i = 0; i < wxStrlen(name)+1; i++)
-        cname[i] = (char) name[i];
+    m_nulLen = (size_t)-2;
+
+    // iconv operates with chars, not wxChars, but luckily it uses only ASCII
+    // names for the charsets
+    const wxCharBuffer cname(wxString(name).ToAscii());
 
     // check for charset that represents wchar_t:
-    if (ms_wcCharsetName == NULL)
+    if ( ms_wcCharsetName.empty() )
     {
-        ms_wcNeedsSwap = false;
+        wxLogTrace(TRACE_STRCONV, _T("Looking for wide char codeset:"));
 
-        // try charset with explicit bytesex info (e.g. "UCS-4LE"):
-        ms_wcCharsetName = WC_NAME_BEST;
-        m2w = iconv_open(ms_wcCharsetName, cname);
+#if wxUSE_FONTMAP
+        const wxChar **names = wxFontMapperBase::GetAllEncodingNames(WC_ENC);
+#else // !wxUSE_FONTMAP
+        static const wxChar *names[] =
+        {
+#if SIZEOF_WCHAR_T == 4
+            _T("UCS-4"),
+#elif SIZEOF_WCHAR_T = 2
+            _T("UCS-2"),
+#endif
+            NULL
+        };
+#endif // wxUSE_FONTMAP/!wxUSE_FONTMAP
 
-        if (m2w == (iconv_t)-1)
+        for ( ; *names && ms_wcCharsetName.empty(); ++names )
         {
-            // try charset w/o bytesex info (e.g. "UCS4")
-            // and check for bytesex ourselves:
-            ms_wcCharsetName = WC_NAME;
-            m2w = iconv_open(ms_wcCharsetName, cname);
+            const wxString nameCS(*names);
 
-            // last bet, try if it knows WCHAR_T pseudo-charset
-            if (m2w == (iconv_t)-1)
-            {
-                ms_wcCharsetName = "WCHAR_T";
-                m2w = iconv_open(ms_wcCharsetName, cname);
-            }
+            // first try charset with explicit bytesex info (e.g. "UCS-4LE"):
+            wxString nameXE(nameCS);
+            #ifdef WORDS_BIGENDIAN
+                nameXE += _T("BE");
+            #else // little endian
+                nameXE += _T("LE");
+            #endif
 
-            if (m2w != (iconv_t)-1)
+            wxLogTrace(TRACE_STRCONV, _T("  trying charset \"%s\""),
+                       nameXE.c_str());
+
+            m2w = iconv_open(nameXE.ToAscii(), cname);
+            if ( m2w == ICONV_T_INVALID )
             {
-                char    buf[2], *bufPtr;
-                wchar_t wbuf[2], *wbufPtr;
-                size_t  insz, outsz;
-                size_t  res;
-
-                buf[0] = 'A';
-                buf[1] = 0;
-                wbuf[0] = 0;
-                insz = 2;
-                outsz = SIZEOF_WCHAR_T * 2;
-                wbufPtr = wbuf;
-                bufPtr = buf;
-
-                res = iconv(m2w, ICONV_CHAR_CAST(&bufPtr), &insz,
-                            (char**)&wbufPtr, &outsz);
-
-                if (ICONV_FAILED(res, insz))
-                {
-                    ms_wcCharsetName = NULL;
-                    wxLogLastError(wxT("iconv"));
-                    wxLogError(_("Conversion to charset '%s' doesn't work."), name);
-                }
-                else
+                // try charset w/o bytesex info (e.g. "UCS4")
+                wxLogTrace(TRACE_STRCONV, _T("  trying charset \"%s\""),
+                           nameCS.c_str());
+                m2w = iconv_open(nameCS.ToAscii(), cname);
+
+                // and check for bytesex ourselves:
+                if ( m2w != ICONV_T_INVALID )
                 {
-                    ms_wcNeedsSwap = wbuf[0] != (wchar_t)buf[0];
+                    char    buf[2], *bufPtr;
+                    wchar_t wbuf[2], *wbufPtr;
+                    size_t  insz, outsz;
+                    size_t  res;
+
+                    buf[0] = 'A';
+                    buf[1] = 0;
+                    wbuf[0] = 0;
+                    insz = 2;
+                    outsz = SIZEOF_WCHAR_T * 2;
+                    wbufPtr = wbuf;
+                    bufPtr = buf;
+
+                    res = iconv(m2w, ICONV_CHAR_CAST(&bufPtr), &insz,
+                                (char**)&wbufPtr, &outsz);
+
+                    if (ICONV_FAILED(res, insz))
+                    {
+                        wxLogLastError(wxT("iconv"));
+                        wxLogError(_("Conversion to charset '%s' doesn't work."),
+                                   nameCS.c_str());
+                    }
+                    else // ok, can convert to this encoding, remember it
+                    {
+                        ms_wcCharsetName = nameCS;
+                        ms_wcNeedsSwap = wbuf[0] != (wchar_t)buf[0];
+                    }
                 }
             }
-            else
+            else // use charset not requiring byte swapping
             {
-                ms_wcCharsetName = NULL;
-
-                // VS: we must not output an error here, since wxWidgets will safely
-                //     fall back to using wxEncodingConverter.
-                wxLogTrace(wxT("strconv"), wxT("Impossible to convert to/from charset '%s' with iconv, falling back to wxEncodingConverter."), name);
-                //wxLogError(
+                ms_wcCharsetName = nameXE;
             }
         }
-        wxLogTrace(wxT("strconv"), wxT("wchar_t charset is '%s', needs swap: %i"), ms_wcCharsetName, ms_wcNeedsSwap);
+
+        wxLogTrace(TRACE_STRCONV,
+                   wxT("iconv wchar_t charset is \"%s\"%s"),
+                   ms_wcCharsetName.empty() ? _T("<none>")
+                                            : ms_wcCharsetName.c_str(),
+                   ms_wcNeedsSwap ? _T(" (needs swap)")
+                                  : _T(""));
     }
     else // we already have ms_wcCharsetName
     {
-        m2w = iconv_open(ms_wcCharsetName, cname);
+        m2w = iconv_open(ms_wcCharsetName.ToAscii(), cname);
     }
 
-    // NB: don't ever pass NULL to iconv_open(), it may crash!
-    if ( ms_wcCharsetName )
+    if ( ms_wcCharsetName.empty() )
     {
-        w2m = iconv_open( cname, ms_wcCharsetName);
+        w2m = ICONV_T_INVALID;
     }
     else
     {
-        w2m = (iconv_t)-1;
+        w2m = iconv_open(cname, ms_wcCharsetName.ToAscii());
+        if ( w2m == ICONV_T_INVALID )
+        {
+            wxLogTrace(TRACE_STRCONV,
+                       wxT("\"%s\" -> \"%s\" works but not the converse!?"),
+                       ms_wcCharsetName.c_str(), cname.data());
+        }
     }
 }
 
 wxMBConv_iconv::~wxMBConv_iconv()
 {
-    if ( m2w != (iconv_t)-1 )
+    if ( m2w != ICONV_T_INVALID )
         iconv_close(m2w);
-    if ( w2m != (iconv_t)-1 )
+    if ( w2m != ICONV_T_INVALID )
         iconv_close(w2m);
 }
 
@@ -1309,7 +1517,7 @@ size_t wxMBConv_iconv::MB2WC(wchar_t *buf, const char *psz, size_t n) const
     //     as MB<->WC conversion would fail "randomly".
     wxMutexLocker lock(wxConstCast(this, wxMBConv_iconv)->m_iconvMutex);
 #endif
+
     size_t inbuf = strlen(psz);
     size_t outbuf = n * SIZEOF_WCHAR_T;
     size_t res, cres;
@@ -1328,7 +1536,8 @@ size_t wxMBConv_iconv::MB2WC(wchar_t *buf, const char *psz, size_t n) const
         if (ms_wcNeedsSwap)
         {
             // convert to native endianness
-            WC_BSWAP(buf /* _not_ bufPtr */, res)
+            for ( unsigned i = 0; i < res; i++ )
+                buf[n] = WC_BSWAP(buf[i]);
         }
 
         // NB: iconv was given only strlen(psz) characters on input, and so
@@ -1358,7 +1567,7 @@ size_t wxMBConv_iconv::MB2WC(wchar_t *buf, const char *psz, size_t n) const
     if (ICONV_FAILED(cres, inbuf))
     {
         //VS: it is ok if iconv fails, hence trace only
-        wxLogTrace(wxT("strconv"), wxT("iconv failed: %s"), wxSysErrorMsg(wxSysErrorCode()));
+        wxLogTrace(TRACE_STRCONV, wxT("iconv failed: %s"), wxSysErrorMsg(wxSysErrorCode()));
         return (size_t)-1;
     }
 
@@ -1371,8 +1580,9 @@ size_t wxMBConv_iconv::WC2MB(char *buf, const wchar_t *psz, size_t n) const
     // NB: explained in MB2WC
     wxMutexLocker lock(wxConstCast(this, wxMBConv_iconv)->m_iconvMutex);
 #endif
-    
-    size_t inbuf = wxWcslen(psz) * SIZEOF_WCHAR_T;
+
+    size_t inlen = wxWcslen(psz);
+    size_t inbuf = inlen * SIZEOF_WCHAR_T;
     size_t outbuf = n;
     size_t res, cres;
 
@@ -1381,13 +1591,13 @@ size_t wxMBConv_iconv::WC2MB(char *buf, const wchar_t *psz, size_t n) const
     if (ms_wcNeedsSwap)
     {
         // need to copy to temp buffer to switch endianness
-        // this absolutely doesn't rock!
-        // (no, doing WC_BSWAP twice on the original buffer won't help, as it
+        // (doing WC_BSWAP twice on the original buffer won't help, as it
         //  could be in read-only memory, or be accessed in some other thread)
-        tmpbuf=(wchar_t*)malloc((inbuf+1)*SIZEOF_WCHAR_T);
-        memcpy(tmpbuf,psz,(inbuf+1)*SIZEOF_WCHAR_T);
-        WC_BSWAP(tmpbuf, inbuf)
-        psz=tmpbuf;
+        tmpbuf = (wchar_t *)malloc(inbuf + SIZEOF_WCHAR_T);
+        for ( size_t i = 0; i < inlen; i++ )
+            tmpbuf[n] = WC_BSWAP(psz[i]);
+        tmpbuf[inlen] = L'\0';
+        psz = tmpbuf;
     }
 
     if (buf)
@@ -1425,14 +1635,43 @@ size_t wxMBConv_iconv::WC2MB(char *buf, const wchar_t *psz, size_t n) const
 
     if (ICONV_FAILED(cres, inbuf))
     {
-        //VS: it is ok if iconv fails, hence trace only
-        wxLogTrace(wxT("strconv"), wxT("iconv failed: %s"), wxSysErrorMsg(wxSysErrorCode()));
+        wxLogTrace(TRACE_STRCONV, wxT("iconv failed: %s"), wxSysErrorMsg(wxSysErrorCode()));
         return (size_t)-1;
     }
 
     return res;
 }
 
+const char *wxMBConv_iconv::GetMBNul(size_t *nulLen) const
+{
+    if ( m_nulLen == (size_t)-2 )
+    {
+        wxMBConv_iconv * const self = wxConstCast(this, wxMBConv_iconv);
+
+#if wxUSE_THREADS
+        // NB: explained in MB2WC
+        wxMutexLocker lock(self->m_iconvMutex);
+#endif
+
+        wchar_t *wnul = L"";
+        size_t inLen = sizeof(wchar_t),
+               outLen = WXSIZEOF(m_nulBuf);
+        const char *in = (char *)wnul;
+        char *out = self->m_nulBuf;
+        if ( iconv(w2m, &in, &inLen, &out, &outLen) == (size_t)-1 )
+        {
+            self->m_nulLen = (size_t)-1;
+        }
+        else // ok
+        {
+            self->m_nulLen = out - m_nulBuf;
+        }
+    }
+
+    *nulLen = m_nulLen;
+    return m_nulBuf;
+}
+
 #endif // HAVE_ICONV
 
 
@@ -1454,19 +1693,22 @@ public:
     wxMBConv_win32()
     {
         m_CodePage = CP_ACP;
+        m_nulLen = (size_t)-2;
     }
 
 #if wxUSE_FONTMAP
     wxMBConv_win32(const wxChar* name)
     {
         m_CodePage = wxCharsetToCodepage(name);
+        m_nulLen = (size_t)-2;
     }
 
     wxMBConv_win32(wxFontEncoding encoding)
     {
         m_CodePage = wxEncodingToCodepage(encoding);
+        m_nulLen = (size_t)-2;
     }
-#endif
+#endif // wxUSE_FONTMAP
 
     size_t MB2WC(wchar_t *buf, const char *psz, size_t n) const
     {
@@ -1483,7 +1725,28 @@ public:
         // own wxMBConvUTF7 doesn't detect errors (e.g. lone "+" which is
         // explicitly ill-formed according to RFC 2152) neither so we don't
         // even have any fallback here...
-        int flags = m_CodePage == CP_UTF7 ? 0 : MB_ERR_INVALID_CHARS;
+        //
+        // Moreover, MB_ERR_INVALID_CHARS is only supported on Win 2K SP4 or
+        // Win XP or newer and if it is specified on older versions, conversion
+        // from CP_UTF8 (which can have flags only 0 or MB_ERR_INVALID_CHARS)
+        // fails. So we can only use the flag on newer Windows versions.
+        // Additionally, the flag is not supported by UTF7, symbol and CJK
+        // encodings. See here:
+        //     http://blogs.msdn.com/michkap/archive/2005/04/19/409566.aspx
+        //     http://msdn.microsoft.com/library/en-us/intl/unicode_17si.asp
+        int flags = 0;
+        if ( m_CodePage != CP_UTF7 && m_CodePage != CP_SYMBOL &&
+             m_CodePage < 50000 &&
+             IsAtLeastWin2kSP4() )
+        {
+            flags = MB_ERR_INVALID_CHARS;
+        }
+        else if ( m_CodePage == CP_UTF8 )
+        {
+            // Avoid round-trip in the special case of UTF-8 by using our
+            // own UTF-8 conversion code:
+            return wxMBConvUTF8().MB2WC(buf, psz, n);
+        }
 
         const size_t len = ::MultiByteToWideChar
                              (
@@ -1494,11 +1757,41 @@ public:
                                 buf,            // output string
                                 buf ? n : 0     // size of output buffer
                              );
+        if ( !len )
+        {
+            // function totally failed
+            return (size_t)-1;
+        }
+
+        // if we were really converting and didn't use MB_ERR_INVALID_CHARS,
+        // check if we succeeded, by doing a double trip:
+        if ( !flags && buf )
+        {
+            const size_t mbLen = strlen(psz);
+            wxCharBuffer mbBuf(mbLen);
+            if ( ::WideCharToMultiByte
+                   (
+                      m_CodePage,
+                      0,
+                      buf,
+                      -1,
+                      mbBuf.data(),
+                      mbLen + 1,        // size in bytes, not length
+                      NULL,
+                      NULL
+                   ) == 0 ||
+                  strcmp(mbBuf, psz) != 0 )
+            {
+                // we didn't obtain the same thing we started from, hence
+                // the conversion was lossy and we consider that it failed
+                return (size_t)-1;
+            }
+        }
 
         // note that it returns count of written chars for buf != NULL and size
         // of the needed buffer for buf == NULL so in either case the length of
         // the string (which never includes the terminating NUL) is one less
-        return len ? len - 1 : (size_t)-1;
+        return len 1;
     }
 
     size_t WC2MB(char *buf, const wchar_t *pwz, size_t n) const
@@ -1613,7 +1906,62 @@ private:
         return s_isWin98Or2k == 1;
     }
 
+    static bool IsAtLeastWin2kSP4()
+    {
+#ifdef __WXWINCE__
+        return false;
+#else
+        static int s_isAtLeastWin2kSP4 = -1;
+
+        if ( s_isAtLeastWin2kSP4 == -1 )
+        {
+            OSVERSIONINFOEX ver;
+
+            memset(&ver, 0, sizeof(ver));
+            ver.dwOSVersionInfoSize = sizeof(ver);
+            GetVersionEx((OSVERSIONINFO*)&ver);
+
+            s_isAtLeastWin2kSP4 =
+              ((ver.dwMajorVersion > 5) || // Vista+
+               (ver.dwMajorVersion == 5 && ver.dwMinorVersion > 0) || // XP/2003
+               (ver.dwMajorVersion == 5 && ver.dwMinorVersion == 0 &&
+               ver.wServicePackMajor >= 4)) // 2000 SP4+
+              ? 1 : 0;
+        }
+
+        return s_isAtLeastWin2kSP4 == 1;
+#endif
+    }
+
+    virtual const char *GetMBNul(size_t *nulLen) const
+    {
+        if ( m_nulLen == (size_t)-2 )
+        {
+            wxMBConv_win32 * const self = wxConstCast(this, wxMBConv_win32);
+
+            self->m_nulLen = ::WideCharToMultiByte
+                               (
+                                    m_CodePage,         // code page
+                                    0,                  // no flags
+                                    L"",                // input string
+                                    1,                  // translate just NUL
+                                    self->m_nulBuf,     // output buffer
+                                    WXSIZEOF(m_nulBuf), // and its size
+                                    NULL,               // "replacement" char
+                                    NULL                // [out] was it used?
+                               );
+
+            if ( m_nulLen == 0 )
+                self->m_nulLen = (size_t)-1;
+        }
+
+        *nulLen = m_nulLen;
+        return m_nulBuf;
+    }
+
     long m_CodePage;
+    size_t m_nulLen;
+    char m_nulBuf[8];
 };
 
 #endif // wxHAVE_WIN32_MB2WC
@@ -1899,7 +2247,7 @@ public:
 #if wxUSE_FONTMAP
     wxMBConv_cocoa(const wxChar* name)
     {
-        Init( wxCFStringEncFromFontEnc(wxFontMapper::Get()->CharsetToEncoding(name, false) ) ) ;
+        Init( wxCFStringEncFromFontEnc(wxFontMapperBase::Get()->CharsetToEncoding(name, false) ) ) ;
     }
 #endif
 
@@ -1944,9 +2292,9 @@ public:
 #if SIZEOF_WCHAR_T == 4
         UniChar* szUniCharBuffer = new UniChar[nOutSize];
 #endif
+
         CFStringGetCharacters(theString, theRange, szUniCharBuffer);
-        
+
         CFRelease(theString);
 
         szUniCharBuffer[nOutLength] = '\0' ;
@@ -1956,20 +2304,20 @@ public:
         converter.MB2WC(szOut, (const char*)szUniCharBuffer , nOutSize ) ;
         delete[] szUniCharBuffer;
 #endif
-    
+
         return nOutLength;
     }
 
     size_t WC2MB(char *szOut, const wchar_t *szUnConv, size_t nOutSize) const
     {
         wxASSERT(szUnConv);
-        
+
         size_t nRealOutSize;
         size_t nBufSize = wxWcslen(szUnConv);
         UniChar* szUniBuffer = (UniChar*) szUnConv;
 
 #if SIZEOF_WCHAR_T == 4
-        wxMBConvUTF16BE converter ;
+        wxMBConvUTF16 converter ;
         nBufSize = converter.WC2MB( NULL , szUnConv , 0 );
         szUniBuffer = new UniChar[ (nBufSize / sizeof(UniChar)) + 1] ;
         converter.WC2MB( (char*) szUniBuffer , szUnConv, nBufSize + sizeof(UniChar)) ;
@@ -1991,7 +2339,7 @@ public:
         {
             if (szOut != NULL)
                 CFStringGetCharacters(theString, CFRangeMake(0, nOutSize - 1), (UniChar*) szOut);
-            
+
             nRealOutSize = CFStringGetLength(theString) + 1;
         }
         else
@@ -2004,7 +2352,7 @@ public:
                     //0 tells CFString to return NULL if it meets such a character
                 false, //not an external representation
                 (UInt8*) szOut,
-                nOutSize, 
+                nOutSize,
                 (CFIndex*) &nRealOutSize
                         );
         }
@@ -2020,7 +2368,7 @@ public:
 
     bool IsOk() const
     {
-        return m_encoding != kCFStringEncodingInvalidId && 
+        return m_encoding != kCFStringEncodingInvalidId &&
               CFStringIsEncodingAvailable(m_encoding);
     }
 
@@ -2047,7 +2395,7 @@ public:
 #if wxUSE_FONTMAP
     wxMBConv_mac(const wxChar* name)
     {
-        Init( wxMacGetSystemEncFromFontEnc(wxFontMapper::Get()->CharsetToEncoding(name, false) ) ) ;
+        Init( wxMacGetSystemEncFromFontEnc(wxFontMapperBase::Get()->CharsetToEncoding(name, false) ) ) ;
     }
 #endif
 
@@ -2105,7 +2453,7 @@ public:
         // we have to terminate here, because n might be larger for the trailing zero, and if UniChar
         // is not properly terminated we get random characters at the end
         ubuf[byteOutLen / sizeof( UniChar ) ] = 0 ;
-        wxMBConvUTF16BE converter ;
+        wxMBConvUTF16 converter ;
         res = converter.MB2WC( (buf ? buf : tbuf) , (const char*)ubuf , n ) ;
         free( ubuf ) ;
 #else
@@ -2138,7 +2486,7 @@ public:
         ByteCount byteBufferLen = n ;
         UniChar* ubuf = NULL ;
 #if SIZEOF_WCHAR_T == 4
-        wxMBConvUTF16BE converter ;
+        wxMBConvUTF16 converter ;
         size_t unicharlen = converter.WC2MB( NULL , psz , 0 ) ;
         byteInLen = unicharlen ;
         ubuf = (UniChar*) malloc( byteInLen + 2 ) ;
@@ -2158,7 +2506,7 @@ public:
         if ( buf  && res < n)
         {
             buf[res] = 0;
-            
+
             //we need to double-trip to verify it didn't insert any ? in place
             //of bogus characters
             wxWCharBuffer wcBuf(n);
@@ -2210,7 +2558,7 @@ public:
     wxMBConv_wxwin(const wxChar* name)
     {
         if (name)
-            m_enc = wxFontMapper::Get()->CharsetToEncoding(name, false);
+            m_enc = wxFontMapperBase::Get()->CharsetToEncoding(name, false);
         else
             m_enc = wxFONTENCODING_SYSTEM;
 
@@ -2253,12 +2601,45 @@ public:
     wxFontEncoding m_enc;
     wxEncodingConverter m2w, w2m;
 
+private:
+    virtual const char *GetMBNul(size_t *nulLen) const
+    {
+        switch ( m_enc )
+        {
+            case wxFONTENCODING_UTF16BE:
+            case wxFONTENCODING_UTF16LE:
+                *nulLen = 2;
+                return "\0";
+
+            case wxFONTENCODING_UTF32BE:
+            case wxFONTENCODING_UTF32LE:
+                *nulLen = 4;
+                return "\0\0\0";
+
+            default:
+                *nulLen = 1;
+                return "";
+        }
+    }
+
     // were we initialized successfully?
     bool m_ok;
 
     DECLARE_NO_COPY_CLASS(wxMBConv_wxwin)
 };
 
+// make the constructors available for unit testing
+WXDLLIMPEXP_BASE wxMBConv* new_wxMBConv_wxwin( const wxChar* name )
+{
+    wxMBConv_wxwin* result = new wxMBConv_wxwin( name );
+    if ( !result->IsOk() )
+    {
+        delete result;
+        return 0;
+    }
+    return result;
+}
+
 #endif // wxUSE_FONTMAP
 
 // ============================================================================
@@ -2281,7 +2662,11 @@ wxCSConv::wxCSConv(const wxChar *charset)
         SetName(charset);
     }
 
+#if wxUSE_FONTMAP
+    m_encoding = wxFontMapperBase::GetEncodingFromName(charset);
+#else
     m_encoding = wxFONTENCODING_SYSTEM;
+#endif
 }
 
 wxCSConv::wxCSConv(wxFontEncoding encoding)
@@ -2340,12 +2725,29 @@ void wxCSConv::SetName(const wxChar *charset)
     }
 }
 
+#if wxUSE_FONTMAP
+#include "wx/hashmap.h"
+
+WX_DECLARE_HASH_MAP( wxFontEncoding, wxString, wxIntegerHash, wxIntegerEqual,
+                     wxEncodingNameCache );
+
+static wxEncodingNameCache gs_nameCache;
+#endif
+
 wxMBConv *wxCSConv::DoCreate() const
 {
+#if wxUSE_FONTMAP
+    wxLogTrace(TRACE_STRCONV,
+               wxT("creating conversion for %s"),
+               (m_name ? m_name
+                       : wxFontMapperBase::GetEncodingName(m_encoding).c_str()));
+#endif // wxUSE_FONTMAP
+
     // check for the special case of ASCII or ISO8859-1 charset: as we have
     // special knowledge of it anyhow, we don't need to create a special
     // conversion object
-    if ( m_encoding == wxFONTENCODING_ISO8859_1 )
+    if ( m_encoding == wxFONTENCODING_ISO8859_1 ||
+            m_encoding == wxFONTENCODING_DEFAULT )
     {
         // don't convert at all
         return NULL;
@@ -2366,17 +2768,53 @@ wxMBConv *wxCSConv::DoCreate() const
 #endif // !wxUSE_FONTMAP
     {
         wxString name(m_name);
+        wxFontEncoding encoding(m_encoding);
+
+        if ( !name.empty() )
+        {
+            wxMBConv_iconv *conv = new wxMBConv_iconv(name);
+            if ( conv->IsOk() )
+                return conv;
+
+            delete conv;
 
 #if wxUSE_FONTMAP
-        if ( name.empty() )
-            name = wxFontMapper::Get()->GetEncodingName(m_encoding);
+            encoding =
+                wxFontMapperBase::Get()->CharsetToEncoding(name, false);
 #endif // wxUSE_FONTMAP
+        }
+#if wxUSE_FONTMAP
+        {
+            const wxEncodingNameCache::iterator it = gs_nameCache.find(encoding);
+            if ( it != gs_nameCache.end() )
+            {
+                if ( it->second.empty() )
+                    return NULL;
 
-        wxMBConv_iconv *conv = new wxMBConv_iconv(name);
-        if ( conv->IsOk() )
-            return conv;
+                wxMBConv_iconv *conv = new wxMBConv_iconv(it->second);
+                if ( conv->IsOk() )
+                    return conv;
 
-        delete conv;
+                delete conv;
+            }
+
+            const wxChar** names = wxFontMapperBase::GetAllEncodingNames(encoding);
+
+            for ( ; *names; ++names )
+            {
+                wxMBConv_iconv *conv = new wxMBConv_iconv(*names);
+                if ( conv->IsOk() )
+                {
+                    gs_nameCache[encoding] = *names;
+                    return conv;
+                }
+
+                delete conv;
+            }
+
+            gs_nameCache[encoding] = _T(""); // cache the failure
+        }
+#endif // wxUSE_FONTMAP
     }
 #endif // HAVE_ICONV
 
@@ -2396,7 +2834,9 @@ wxMBConv *wxCSConv::DoCreate() const
 #endif // wxHAVE_WIN32_MB2WC
 #if defined(__WXMAC__)
     {
-        if ( m_name || ( m_encoding < wxFONTENCODING_UTF16BE ) )
+        // leave UTF16 and UTF32 to the built-ins of wx
+        if ( m_name || ( m_encoding < wxFONTENCODING_UTF16BE ||
+            ( m_encoding >= wxFONTENCODING_MACMIN && m_encoding <= wxFONTENCODING_MACMAX ) ) )
         {
 
 #if wxUSE_FONTMAP
@@ -2438,7 +2878,7 @@ wxMBConv *wxCSConv::DoCreate() const
         // use "false" to suppress interactive dialogs -- we can be called from
         // anywhere and popping up a dialog from here is the last thing we want to
         // do
-        enc = wxFontMapper::Get()->CharsetToEncoding(m_name, false);
+        enc = wxFontMapperBase::Get()->CharsetToEncoding(m_name, false);
     }
 #endif // wxUSE_FONTMAP
 
@@ -2494,7 +2934,7 @@ wxMBConv *wxCSConv::DoCreate() const
                    m_name ? m_name
                       :
 #if wxUSE_FONTMAP
-                         wxFontMapper::GetEncodingDescription(m_encoding).c_str()
+                         wxFontMapperBase::GetEncodingDescription(m_encoding).c_str()
 #else // !wxUSE_FONTMAP
                          wxString::Format(_("encoding %s"), m_encoding).c_str()
 #endif // wxUSE_FONTMAP/!wxUSE_FONTMAP
@@ -2574,6 +3014,20 @@ size_t wxCSConv::WC2MB(char *buf, const wchar_t *psz, size_t n) const
     return len;
 }
 
+const char *wxCSConv::GetMBNul(size_t *nulLen) const
+{
+    CreateConvIfNeeded();
+
+    if ( m_convReal )
+    {
+        // cast needed just to call private function of m_convReal
+        return ((wxCSConv *)m_convReal)->GetMBNul(nulLen);
+    }
+
+    *nulLen = 1;
+    return "";
+}
+
 // ----------------------------------------------------------------------------
 // globals
 // ----------------------------------------------------------------------------
@@ -2591,13 +3045,19 @@ static wxCSConv wxConvISO8859_1Obj(wxFONTENCODING_ISO8859_1);
 static wxMBConvUTF7 wxConvUTF7Obj;
 static wxMBConvUTF8 wxConvUTF8Obj;
 
-
 WXDLLIMPEXP_DATA_BASE(wxMBConv&) wxConvLibc = wxConvLibcObj;
 WXDLLIMPEXP_DATA_BASE(wxCSConv&) wxConvLocal = wxConvLocalObj;
 WXDLLIMPEXP_DATA_BASE(wxCSConv&) wxConvISO8859_1 = wxConvISO8859_1Obj;
 WXDLLIMPEXP_DATA_BASE(wxMBConvUTF7&) wxConvUTF7 = wxConvUTF7Obj;
 WXDLLIMPEXP_DATA_BASE(wxMBConvUTF8&) wxConvUTF8 = wxConvUTF8Obj;
 WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvCurrent = &wxConvLibcObj;
+WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvFileName = &
+#ifdef __WXOSX__
+                                    wxConvUTF8Obj;
+#else
+                                    wxConvLibcObj;
+#endif
+
 
 #else // !wxUSE_WCHAR_T
 
@@ -2608,5 +3068,3 @@ WXDLLIMPEXP_DATA_BASE(wxMBConv) wxConvLibc,
                                 wxConvUTF8;
 
 #endif // wxUSE_WCHAR_T/!wxUSE_WCHAR_T
-
-