]> git.saurik.com Git - wxWidgets.git/blobdiff - src/common/strconv.cpp
Fix recursion problems when loading pages from a virtual file system using the WebKit...
[wxWidgets.git] / src / common / strconv.cpp
index 1e36ac81b46a65d66ba36c77ebc1a89386813d22..170ad719bdbd0380c6d06b8de8cf8aaedb37e9d6 100644 (file)
 /////////////////////////////////////////////////////////////////////////////
-// Name:        strconv.cpp
+// Name:        src/common/strconv.cpp
 // Purpose:     Unicode conversion classes
-// Author:      Ove Kaaven, Robert Roebling, Vadim Zeitlin
+// Author:      Ove Kaaven, Robert Roebling, Vadim Zeitlin, Vaclav Slavik,
+//              Ryan Norton, Fredrik Roubert (UTF7)
 // Modified by:
 // Created:     29/01/98
 // RCS-ID:      $Id$
-// Copyright:   (c) 1999 Ove Kaaven, Robert Roebling, Vadim Zeitlin
-// Licence:     wxWindows license
+// Copyright:   (c) 1999 Ove Kaaven, Robert Roebling, Vaclav Slavik
+//              (c) 2000-2003 Vadim Zeitlin
+//              (c) 2004 Ryan Norton, Fredrik Roubert
+// Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-// ============================================================================
-// declarations
-// ============================================================================
-
-// ----------------------------------------------------------------------------
-// headers
-// ----------------------------------------------------------------------------
-
-#ifdef __GNUG__
-  #pragma implementation "strconv.h"
-#endif
-
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
 #ifdef __BORLANDC__
-  #pragma hdrstop
+    #pragma hdrstop
+#endif  //__BORLANDC__
+
+#ifndef WX_PRECOMP
+    #include "wx/intl.h"
+    #include "wx/log.h"
+    #include "wx/utils.h"
+    #include "wx/hashmap.h"
 #endif
 
-#ifdef __WXMSW__
-  #include "wx/msw/private.h"
-#endif
+#include "wx/strconv.h"
 
+#ifndef __WXWINCE__
 #include <errno.h>
+#endif
+
 #include <ctype.h>
 #include <string.h>
 #include <stdlib.h>
 
-#ifdef __SALFORDC__
-  #include <clib.h>
+#if defined(__WIN32__) && !defined(__WXMICROWIN__)
+    #include "wx/msw/private.h"
+    #include "wx/msw/missing.h"
+    #define wxHAVE_WIN32_MB2WC
 #endif
 
-#ifdef HAVE_ICONV_H
-  #include <iconv.h>
-#endif
-#ifdef HAVE_LANGINFO_H
-  #include <langinfo.h>
+#ifdef HAVE_ICONV
+    #include <iconv.h>
+    #include "wx/thread.h"
 #endif
 
-#ifdef __WXMSW__
-  #include <windows.h>
-#endif
+#include "wx/encconv.h"
+#include "wx/fontmap.h"
 
-#include "wx/debug.h"
-#include "wx/strconv.h"
-#include "wx/intl.h"
-#include "wx/log.h"
+#ifdef __DARWIN__
+#include "wx/osx/core/private/strconv_cf.h"
+#endif //def __DARWIN__
 
-#if defined(WORDS_BIGENDIAN) || defined(__STDC_ISO_10646__)
-#define BSWAP_UCS4(str, len)
-#define BSWAP_UCS2(str, len)
-#else
-#define BSWAP_UCS4(str, len) { unsigned _c; for (_c=0; _c<len; _c++) str[_c]=wxUINT32_SWAP_ALWAYS(str[_c]); }
-#define BSWAP_UCS2(str, len) { unsigned _c; for (_c=0; _c<len; _c++) str[_c]=wxUINT16_SWAP_ALWAYS(str[_c]); }
-#define WC_NEED_BSWAP
-#endif
-#define BSWAP_UTF32(str, len) BSWAP_UCS4(str, len)
-#define BSWAP_UTF16(str, len) BSWAP_UCS2(str, len)
 
-#if SIZEOF_WCHAR_T == 4
-#define WC_NAME "UCS4"
-#define WC_BSWAP BSWAP_UCS4
-#elif SIZEOF_WCHAR_T == 2
-#define WC_NAME "UTF16"
-#define WC_BSWAP BSWAP_UTF16
-#define WC_UTF16
-#endif
+#define TRACE_STRCONV wxT("strconv")
 
-// ----------------------------------------------------------------------------
-// globals
-// ----------------------------------------------------------------------------
+// WC_UTF16 is defined only if sizeof(wchar_t) == 2, otherwise it's supposed to
+// be 4 bytes
+#if SIZEOF_WCHAR_T == 2
+    #define WC_UTF16
+#endif
 
-WXDLLEXPORT_DATA(wxMBConv *) wxConvCurrent = &wxConvLibc;
 
 // ============================================================================
 // implementation
 // ============================================================================
 
-#if wxUSE_WCHAR_T
-
-#ifdef WC_UTF16
-
-static size_t encode_utf16(wxUint32 input,wxUint16*output)
+// helper function of cMB2WC(): check if n bytes at this location are all NUL
+static bool NotAllNULs(const char *p, size_t n)
 {
-  if (input<=0xffff) {
-    if (output) *output++ = input;
-    return 1;
-  } else
-  if (input>=0x110000) {
-    return (size_t)-1;
-  } else {
-    if (output) {
-      *output++ = (input >> 10)+0xd7c0;
-      *output++ = (input&0x3ff)+0xdc00;
-    }
-    return 2;
-  }
-}
+    while ( n && *p++ == '\0' )
+        n--;
 
-static size_t decode_utf16(wxUint16*input,wxUint32&output)
-{
-  if ((*input<0xd800) || (*input>0xdfff)) {
-    output = *input;
-    return 1;
-  } else
-  if ((input[1]<0xdc00) || (input[1]>=0xdfff)) {
-    output = *input;
-    return (size_t)-1;
-  } else {
-    output = ((input[0] - 0xd7c0) << 10) + (input[1] - 0xdc00);
-    return 2;
-  }
+    return n != 0;
 }
 
-#endif // WC_UTF16
-
 // ----------------------------------------------------------------------------
-// wxMBConv
+// UTF-16 en/decoding to/from UCS-4 with surrogates handling
 // ----------------------------------------------------------------------------
 
-WXDLLEXPORT_DATA(wxMBConv) wxConvLibc;
-
-size_t wxMBConv::MB2WC(wchar_t *buf, const char *psz, size_t n) const
-{
-    return wxMB2WC(buf, psz, n);
-}
-
-size_t wxMBConv::WC2MB(char *buf, const wchar_t *psz, size_t n) const
+static size_t encode_utf16(wxUint32 input, wxUint16 *output)
 {
-    return wxWC2MB(buf, psz, n);
-}
+    if (input <= 0xffff)
+    {
+        if (output)
+            *output = (wxUint16) input;
 
-const wxWCharBuffer wxMBConv::cMB2WC(const char *psz) const
-{
-    if (psz)
+        return 1;
+    }
+    else if (input >= 0x110000)
     {
-        size_t nLen = MB2WC((wchar_t *) NULL, psz, 0);
-        if (nLen == (size_t)-1)
-            return wxWCharBuffer((wchar_t *) NULL);
-        wxWCharBuffer buf(nLen);
-        MB2WC((wchar_t *)(const wchar_t *) buf, psz, nLen);
-        return buf;
+        return wxCONV_FAILED;
     }
     else
-        return wxWCharBuffer((wchar_t *) NULL);
+    {
+        if (output)
+        {
+            *output++ = (wxUint16) ((input >> 10) + 0xd7c0);
+            *output = (wxUint16) ((input & 0x3ff) + 0xdc00);
+        }
+
+        return 2;
+    }
 }
 
-const wxCharBuffer wxMBConv::cWC2MB(const wchar_t *psz) const
+static size_t decode_utf16(const wxUint16* input, wxUint32& output)
 {
-    if (psz)
+    if ((*input < 0xd800) || (*input > 0xdfff))
     {
-        size_t nLen = WC2MB((char *) NULL, psz, 0);
-        if (nLen == (size_t)-1)
-            return wxCharBuffer((char *) NULL);
-        wxCharBuffer buf(nLen);
-        WC2MB((char *)(const char *) buf, psz, nLen);
-        return buf;
+        output = *input;
+        return 1;
+    }
+    else if ((input[1] < 0xdc00) || (input[1] > 0xdfff))
+    {
+        output = *input;
+        return wxCONV_FAILED;
     }
     else
-        return wxCharBuffer((char *) NULL);
+    {
+        output = ((input[0] - 0xd7c0) << 10) + (input[1] - 0xdc00);
+        return 2;
+    }
 }
 
-// ----------------------------------------------------------------------------
-// standard file conversion
-// ----------------------------------------------------------------------------
-
-WXDLLEXPORT_DATA(wxMBConvFile) wxConvFile;
-
-// just use the libc conversion for now
-size_t wxMBConvFile::MB2WC(wchar_t *buf, const char *psz, size_t n) const
+#ifdef WC_UTF16
+    typedef wchar_t wxDecodeSurrogate_t;
+#else // !WC_UTF16
+    typedef wxUint16 wxDecodeSurrogate_t;
+#endif // WC_UTF16/!WC_UTF16
+
+// returns the next UTF-32 character from the wchar_t buffer and advances the
+// pointer to the character after this one
+//
+// if an invalid character is found, *pSrc is set to NULL, the caller must
+// check for this
+static wxUint32 wxDecodeSurrogate(const wxDecodeSurrogate_t **pSrc)
 {
-    return wxMB2WC(buf, psz, n);
-}
+    wxUint32 out;
+    const size_t
+        n = decode_utf16(reinterpret_cast<const wxUint16 *>(*pSrc), out);
+    if ( n == wxCONV_FAILED )
+        *pSrc = NULL;
+    else
+        *pSrc += n;
 
-size_t wxMBConvFile::WC2MB(char *buf, const wchar_t *psz, size_t n) const
-{
-    return wxWC2MB(buf, psz, n);
+    return out;
 }
 
 // ----------------------------------------------------------------------------
-// standard gdk conversion
+// wxMBConv
 // ----------------------------------------------------------------------------
 
-#ifdef __WXGTK12__
-
-WXDLLEXPORT_DATA(wxMBConvGdk) wxConvGdk;
-
-#include <gdk/gdk.h>
-
-size_t wxMBConvGdk::MB2WC(wchar_t *buf, const char *psz, size_t n) const
+size_t
+wxMBConv::ToWChar(wchar_t *dst, size_t dstLen,
+                  const char *src, size_t srcLen) const
 {
-  if (buf) {
-    return gdk_mbstowcs((GdkWChar *)buf, psz, n);
-  } else {
-    GdkWChar *nbuf = new GdkWChar[n=strlen(psz)];
-    size_t len = gdk_mbstowcs(nbuf, psz, n);
-    delete [] nbuf;
-    return len;
-  }
-}
+    // although new conversion classes are supposed to implement this function
+    // directly, the existing ones only implement the old MB2WC() and so, to
+    // avoid to have to rewrite all conversion classes at once, we provide a
+    // default (but not efficient) implementation of this one in terms of the
+    // old function by copying the input to ensure that it's NUL-terminated and
+    // then using MB2WC() to convert it
+    //
+    // moreover, some conversion classes simply can't implement ToWChar()
+    // directly, the primary example is wxConvLibc: mbstowcs() only handles
+    // NUL-terminated strings
+
+    // the number of chars [which would be] written to dst [if it were not NULL]
+    size_t dstWritten = 0;
+
+    // the number of NULs terminating this string
+    size_t nulLen = 0;  // not really needed, but just to avoid warnings
+
+    // if we were not given the input size we just have to assume that the
+    // string is properly terminated as we have no way of knowing how long it
+    // is anyhow, but if we do have the size check whether there are enough
+    // NULs at the end
+    wxCharBuffer bufTmp;
+    const char *srcEnd;
+    if ( srcLen != wxNO_LEN )
+    {
+        // we need to know how to find the end of this string
+        nulLen = GetMBNulLen();
+        if ( nulLen == wxCONV_FAILED )
+            return wxCONV_FAILED;
 
-size_t wxMBConvGdk::WC2MB(char *buf, const wchar_t *psz, size_t n) const
-{
-  char *mbstr = gdk_wcstombs((GdkWChar *)psz);
-  size_t len = mbstr ? strlen(mbstr) : 0;
-  if (buf) {
-    if (len > n) len = n;
-    memcpy(buf, psz, len);
-    if (len < n) buf[len] = 0;
-  }
-  return len;
-}
+        // if there are enough NULs we can avoid the copy
+        if ( srcLen < nulLen || NotAllNULs(src + srcLen - nulLen, nulLen) )
+        {
+            // make a copy in order to properly NUL-terminate the string
+            bufTmp = wxCharBuffer(srcLen + nulLen - 1 /* 1 will be added */);
+            char * const p = bufTmp.data();
+            memcpy(p, src, srcLen);
+            for ( char *s = p + srcLen; s < p + srcLen + nulLen; s++ )
+                *s = '\0';
+
+            src = bufTmp;
+        }
 
-#endif // GTK > 1.0
+        srcEnd = src + srcLen;
+    }
+    else // quit after the first loop iteration
+    {
+        srcEnd = NULL;
+    }
 
-// ----------------------------------------------------------------------------
-// UTF-7
-// ----------------------------------------------------------------------------
+    // the idea of this code is straightforward: it converts a NUL-terminated
+    // chunk of the string during each iteration and updates the output buffer
+    // with the result
+    //
+    // all the complication come from the fact that this function, for
+    // historical reasons, must behave in 2 subtly different ways when it's
+    // called with a fixed number of characters and when it's called for the
+    // entire NUL-terminated string: in the former case (srcEnd != NULL) we
+    // must count all characters we convert, NUL or not; but in the latter we
+    // do not count the trailing NUL -- but still count all the NULs inside the
+    // string
+    //
+    // so for the (simple) former case we just always count the trailing NUL,
+    // but for the latter we need to wait until we see if there is going to be
+    // another loop iteration and only count it then
+    for ( ;; )
+    {
+        // try to convert the current chunk
+        size_t lenChunk = MB2WC(NULL, src, 0);
+        if ( lenChunk == wxCONV_FAILED )
+            return wxCONV_FAILED;
 
-WXDLLEXPORT_DATA(wxMBConvUTF7) wxConvUTF7;
+        dstWritten += lenChunk;
+        if ( !srcEnd )
+            dstWritten++;
 
-#if 0
-static char utf7_setD[]="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-                        "abcdefghijklmnopqrstuvwxyz"
-                        "0123456789'(),-./:?";
-static char utf7_setO[]="!\"#$%&*;<=>@[]^_`{|}";
-static char utf7_setB[]="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-                        "abcdefghijklmnopqrstuvwxyz"
-                        "0123456789+/";
-#endif
+        if ( !lenChunk )
+        {
+            // nothing left in the input string, conversion succeeded
+            break;
+        }
 
-// TODO: write actual implementations of UTF-7 here
-size_t wxMBConvUTF7::MB2WC(wchar_t * WXUNUSED(buf),
-                           const char * WXUNUSED(psz),
-                           size_t WXUNUSED(n)) const
-{
-  return 0;
-}
+        if ( dst )
+        {
+            if ( dstWritten > dstLen )
+                return wxCONV_FAILED;
 
-size_t wxMBConvUTF7::WC2MB(char * WXUNUSED(buf),
-                           const wchar_t * WXUNUSED(psz),
-                           size_t WXUNUSED(n)) const
-{
-  return 0;
-}
+            // +1 is for trailing NUL
+            if ( MB2WC(dst, src, lenChunk + 1) == wxCONV_FAILED )
+                return wxCONV_FAILED;
 
-// ----------------------------------------------------------------------------
-// UTF-8
-// ----------------------------------------------------------------------------
+            dst += lenChunk;
+            if ( !srcEnd )
+                dst++;
+        }
 
-WXDLLEXPORT_DATA(wxMBConvUTF8) wxConvUTF8;
-
-static wxUint32 utf8_max[]={0x7f,0x7ff,0xffff,0x1fffff,0x3ffffff,0x7fffffff,0xffffffff};
-
-size_t wxMBConvUTF8::MB2WC(wchar_t *buf, const char *psz, size_t n) const
-{
-  size_t len = 0;
-
-  while (*psz && ((!buf) || (len<n))) {
-    unsigned char cc=*psz++, fc=cc;
-    unsigned cnt;
-    for (cnt=0; fc&0x80; cnt++) fc<<=1;
-    if (!cnt) {
-      // plain ASCII char
-      if (buf) *buf++=cc;
-      len++;
-    } else {
-      cnt--;
-      if (!cnt) {
-        // invalid UTF-8 sequence
-        return (size_t)-1;
-      } else {
-        unsigned ocnt=cnt-1;
-        wxUint32 res=cc&(0x3f>>cnt);
-        while (cnt--) {
-          cc = *psz++;
-          if ((cc&0xC0)!=0x80) {
-            // invalid UTF-8 sequence
-            return (size_t)-1;
-          }
-          res=(res<<6)|(cc&0x3f);
-        }
-        if (res<=utf8_max[ocnt]) {
-          // illegal UTF-8 encoding
-          return (size_t)-1;
+        if ( !srcEnd )
+        {
+            // we convert just one chunk in this case as this is the entire
+            // string anyhow (and we don't count the trailing NUL in this case)
+            break;
         }
-#ifdef WC_UTF16
-        size_t pa = encode_utf16(res, buf);
-        if (pa == (size_t)-1)
-          return (size_t)-1;
-        if (buf) buf+=pa;
-        len+=pa;
-#else
-        if (buf) *buf++=res;
-        len++;
-#endif
-      }
-    }
-  }
-  if (buf && (len<n)) *buf = 0;
-  return len;
-}
 
-size_t wxMBConvUTF8::WC2MB(char *buf, const wchar_t *psz, size_t n) const
-{
-  size_t len = 0;
+        // advance the input pointer past the end of this chunk: notice that we
+        // will always stop before srcEnd because we know that the chunk is
+        // always properly NUL-terminated
+        while ( NotAllNULs(src, nulLen) )
+        {
+            // notice that we must skip over multiple bytes here as we suppose
+            // that if NUL takes 2 or 4 bytes, then all the other characters do
+            // too and so if advanced by a single byte we might erroneously
+            // detect sequences of NUL bytes in the middle of the input
+            src += nulLen;
+        }
 
-  while (*psz && ((!buf) || (len<n))) {
-    wxUint32 cc;
-#ifdef WC_UTF16
-    size_t pa = decode_utf16(psz,cc);
-    psz += (pa == (size_t)-1) ? 1 : pa;
-#else
-    cc=(*psz++)&0x7fffffff;
-#endif
-    unsigned cnt;
-    for (cnt=0; cc>utf8_max[cnt]; cnt++);
-    if (!cnt) {
-      // plain ASCII char
-      if (buf) *buf++=cc;
-      len++;
-    } else {
-      len+=cnt+1;
-      if (buf) {
-        *buf++=(-128>>cnt)|((cc>>(cnt*6))&(0x3f>>cnt));
-        while (cnt--)
-          *buf++=0x80|((cc>>(cnt*6))&0x3f);
-      }
-    }
-  }
-  if (buf && (len<n)) *buf = 0;
-  return len;
-}
+        // if the buffer ends before this NUL, we shouldn't count it in our
+        // output so skip the code below
+        if ( src == srcEnd )
+            break;
 
-// ----------------------------------------------------------------------------
-// specified character set
-// ----------------------------------------------------------------------------
+        // do count this terminator as it's inside the buffer we convert
+        dstWritten++;
+        if ( dst )
+            dst++;
 
-WXDLLEXPORT_DATA(wxCSConv) wxConvLocal((const wxChar *)NULL);
+        src += nulLen; // skip the terminator itself
 
-#include "wx/encconv.h"
-#include "wx/fontmap.h"
+        if ( src >= srcEnd )
+            break;
+    }
 
-// TODO: add some tables here
-// - perhaps common encodings to common codepages (for Win32)
-// - perhaps common encodings to objects ("UTF8" -> wxConvUTF8)
-// - move wxEncodingConverter meat in here
-
-#ifdef __WIN32__
-#include "wx/msw/registry.h"
-// this should work if M$ Internet Exploiter is installed
-static long CharsetToCodepage(const wxChar *name)
-{
-    if (!name) 
-        return GetACP();
-        
-    long CP=-1;
-    
-    wxString cn(name);
-    do {
-        wxString path( wxT("MIME\\Database\\Charset\\") );
-        path += cn;
-        wxRegKey key( wxRegKey::HKCR, path );
-
-        /* two cases: either there's an AliasForCharset string,
-         * or there are Codepage and InternetEncoding dwords.
-         * The InternetEncoding gives us the actual encoding,
-         * the Codepage just says which Windows character set to
-         * use when displaying the data.
-         */
-        if (key.QueryValue( wxT("InternetEncoding"), &CP )) break;
-        
-        // no encoding, see if it's an alias
-        if (!key.QueryValue( wxT("AliasForCharset"), cn )) break;
-    } while (1);
-    
-    return CP;
+    return dstWritten;
 }
-#endif
-
-class wxCharacterSet
-{
-public:
-    wxCharacterSet(const wxChar*name)
-        : cname(name) {}
-    virtual ~wxCharacterSet()
-        {}
-    virtual size_t MB2WC(wchar_t*buf, const char*psz, size_t n) 
-        { return (size_t)-1; }
-    virtual size_t WC2MB(char*buf, const wchar_t*psz, size_t n)
-        { return (size_t)-1; }
-    virtual bool usable()
-        { return FALSE; }
-public:
-    const wxChar*cname;
-};
-
-class ID_CharSet : public wxCharacterSet
-{
-public:
-    ID_CharSet(const wxChar*name,wxMBConv*cnv)
-        : wxCharacterSet(name), work(cnv) {}
-        
-    size_t MB2WC(wchar_t*buf, const char*psz, size_t n)
-        { return work ? work->MB2WC(buf,psz,n) : (size_t)-1; }
-        
-    size_t WC2MB(char*buf, const wchar_t*psz, size_t n)
-        { return work ? work->WC2MB(buf,psz,n) : (size_t)-1; }
-        
-    bool usable()
-        { return work!=NULL; }
-public:
-    wxMBConv*work;
-};
-
 
-#ifdef HAVE_ICONV_H
-
-// VS: glibc 2.1.3 is broken in that iconv() conversion to/from UCS4 fails with E2BIG
-//     if output buffer is _exactly_ as big as needed. Such case is (unless there's
-//     yet another bug in glibc) the only case when iconv() returns with (size_t)-1
-//     (which means error) and says there are 0 bytes left in the input buffer --
-//     when _real_ error occurs, bytes-left-in-input buffer is non-zero. Hence,
-//     this alternative test for iconv() failure.
-//     [This bug does not appear in glibc 2.2.]
-#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ <= 1
-#define ICONV_FAILED(cres, bufLeft) ((cres == (size_t)-1) && \
-                                     (errno != E2BIG || bufLeft != 0))
-#else
-#define ICONV_FAILED(cres, bufLeft)  (cres == (size_t)-1)
-#endif
-
-class IC_CharSet : public wxCharacterSet
+size_t
+wxMBConv::FromWChar(char *dst, size_t dstLen,
+                    const wchar_t *src, size_t srcLen) const
 {
-public:
-    IC_CharSet(const wxChar*name) 
-        : wxCharacterSet(name)
+    // the number of chars [which would be] written to dst [if it were not NULL]
+    size_t dstWritten = 0;
+
+    // if we don't know its length we have no choice but to assume that it is
+    // NUL-terminated (notice that it can still be NUL-terminated even if
+    // explicit length is given but it doesn't change our return value)
+    const bool isNulTerminated = srcLen == wxNO_LEN;
+
+    // make a copy of the input string unless it is already properly
+    // NUL-terminated
+    wxWCharBuffer bufTmp;
+    if ( isNulTerminated )
     {
-        m2w = iconv_open(WC_NAME, wxConvLibc.cWX2MB(cname));
-        w2m = iconv_open(wxConvLibc.cWX2MB(cname), WC_NAME);
+        srcLen = wxWcslen(src) + 1;
     }
-    
-    ~IC_CharSet()
+    else if ( srcLen != 0 && src[srcLen - 1] != L'\0' )
     {
-        if ( m2w != (iconv_t)-1 ) 
-            iconv_close(m2w);
-        if ( w2m != (iconv_t)-1 ) 
-            iconv_close(w2m);
+        // make a copy in order to properly NUL-terminate the string
+        bufTmp = wxWCharBuffer(srcLen);
+        memcpy(bufTmp.data(), src, srcLen * sizeof(wchar_t));
+        src = bufTmp;
     }
-    
-    size_t MB2WC(wchar_t *buf, const char *psz, size_t n)
+
+    const size_t lenNul = GetMBNulLen();
+    for ( const wchar_t * const srcEnd = src + srcLen;
+          src < srcEnd;
+          src++ /* skip L'\0' too */ )
     {
-        size_t inbuf = strlen(psz);
-        size_t outbuf = n * SIZEOF_WCHAR_T;
-        size_t res, cres;
-        // VS: Use these instead of psz, buf because iconv() modifies its arguments:
-        wchar_t *bufPtr = buf;
-        const char *pszPtr = psz;
+        // try to convert the current chunk
+        size_t lenChunk = WC2MB(NULL, src, 0);
+        if ( lenChunk == wxCONV_FAILED )
+            return wxCONV_FAILED;
 
-        if (buf)
-        {
-            // have destination buffer, convert there
-#ifdef WX_ICONV_TAKES_CHAR
-            cres = iconv(m2w, (char**)&pszPtr, &inbuf, (char**)&bufPtr, &outbuf);
-#else
-            cres = iconv(m2w, &pszPtr, &inbuf, (char**)&bufPtr, &outbuf);
-#endif
-            res = n - (outbuf / SIZEOF_WCHAR_T);
-            // convert to native endianness
-#ifdef WC_NEED_BSWAP
-            WC_BSWAP(buf /* _not_ bufPtr */, res)
-#endif
-        }
-        else
+        dstWritten += lenChunk;
+
+        const wchar_t * const
+            chunkEnd = isNulTerminated ? srcEnd - 1 : src + wxWcslen(src);
+
+        // our return value accounts for the trailing NUL(s), unlike that of
+        // WC2MB(), however don't do it for the last NUL we artificially added
+        // ourselves above
+        if ( chunkEnd < srcEnd )
+            dstWritten += lenNul;
+
+        if ( dst )
         {
-            // no destination buffer... convert using temp buffer
-            // to calculate destination buffer requirement
-            wchar_t tbuf[8];
-            res = 0;
-            do {
-                bufPtr = tbuf; outbuf = 8*SIZEOF_WCHAR_T;
-#ifdef WX_ICONV_TAKES_CHAR
-                cres = iconv( m2w, (char**)&pszPtr, &inbuf, (char**)&bufPtr, &outbuf );
-#else
-                cres = iconv( m2w, &pszPtr, &inbuf, (char**)&bufPtr, &outbuf );
-#endif
-                res += 8-(outbuf/SIZEOF_WCHAR_T);
-            } while ((cres==(size_t)-1) && (errno==E2BIG));
+            if ( dstWritten > dstLen )
+                return wxCONV_FAILED;
+
+            // if we know that there is enough space in the destination buffer
+            // (because we accounted for lenNul in dstWritten above), we can
+            // convert directly in place -- but otherwise we need another
+            // temporary buffer to ensure that we don't overwrite the output
+            wxCharBuffer dstBuf;
+            char *dstTmp;
+            if ( chunkEnd == srcEnd )
+            {
+                dstBuf = wxCharBuffer(lenChunk + lenNul - 1);
+                dstTmp = dstBuf.data();
+            }
+            else
+            {
+                dstTmp = dst;
+            }
+
+            if ( WC2MB(dstTmp, src, lenChunk + lenNul) == wxCONV_FAILED )
+                return wxCONV_FAILED;
+
+            if ( dstTmp != dst )
+            {
+                // copy everything up to but excluding the terminating NUL(s)
+                // into the real output buffer
+                memcpy(dst, dstTmp, lenChunk);
+
+                // micro-optimization: if dstTmp != dst it means that chunkEnd
+                // == srcEnd and so we're done, no need to update anything below
+                break;
+            }
+
+            dst += lenChunk;
+            if ( chunkEnd < srcEnd )
+                dst += lenNul;
         }
-        
-        if (ICONV_FAILED(cres, inbuf))
-            return (size_t)-1;
 
-        return res;
+        src = chunkEnd;
     }
-    
-    size_t WC2MB(char*buf, const wchar_t*psz, size_t n)
-    {
-#if defined(__BORLANDC__) && (__BORLANDC__ > 0x530)
-        size_t inbuf = std::wcslen(psz) * SIZEOF_WCHAR_T;
-#else
-        size_t inbuf = ::wcslen(psz) * SIZEOF_WCHAR_T;
-#endif
-        size_t outbuf = n;
-        size_t res, cres;
 
-#ifdef WC_NEED_BSWAP
-        // 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
-        //  could be in read-only memory, or be accessed in some other thread)
-        wchar_t*tmpbuf=(wchar_t*)malloc((inbuf+1)*SIZEOF_WCHAR_T);
-        memcpy(tmpbuf,psz,(inbuf+1)*SIZEOF_WCHAR_T);
-        WC_BSWAP(tmpbuf, inbuf)
-        psz=tmpbuf;
-#endif
-        if (buf)
-        {
-            // have destination buffer, convert there
-#ifdef WX_ICONV_TAKES_CHAR
-            cres = iconv( w2m, (char**)&psz, &inbuf, &buf, &outbuf );
-#else
-            cres = iconv( w2m, (const char**)&psz, &inbuf, &buf, &outbuf );
-#endif
-            res = n-outbuf;
-        }
-        else
-        {
-            // no destination buffer... convert using temp buffer
-            // to calculate destination buffer requirement
-            char tbuf[16];
-            res = 0;
-            do {
-                buf = tbuf; outbuf = 16;
-#ifdef WX_ICONV_TAKES_CHAR
-                cres = iconv( w2m, (char**)&psz, &inbuf, &buf, &outbuf );
-#else
-                cres = iconv( w2m, (const char**)&psz, &inbuf, &buf, &outbuf );
-#endif
-                res += 16 - outbuf;
-            } while ((cres==(size_t)-1) && (errno==E2BIG));
-        }
-#ifdef WC_NEED_BSWAP
-        free(tmpbuf);
-#endif
-        if (ICONV_FAILED(cres, inbuf))
-            return (size_t)-1;
-            
-        return res;
-    }
-    
-    bool usable()
-        { return (m2w != (iconv_t)-1) && (w2m != (iconv_t)-1); }
-  
-public:
-    iconv_t m2w, w2m;
-};
-#endif
+    return dstWritten;
+}
 
-#ifdef __WIN32__
-class CP_CharSet : public wxCharacterSet
+size_t wxMBConv::MB2WC(wchar_t *outBuff, const char *inBuff, size_t outLen) const
 {
-public:
-    CP_CharSet(const wxChar*name) 
-        : wxCharacterSet(name), CodePage(CharsetToCodepage(name)) {}
-        
-    size_t MB2WC(wchar_t*buf, const char*psz, size_t n)
-    {
-        size_t len = MultiByteToWideChar(CodePage,0,psz,-1,buf,buf?n:0);
-        return len ? len : (size_t)-1;
-    }
-    
-    size_t WC2MB(char*buf, const wchar_t*psz, size_t n)
+    size_t rc = ToWChar(outBuff, outLen, inBuff);
+    if ( rc != wxCONV_FAILED )
     {
-        size_t len = WideCharToMultiByte(CodePage,0,psz,-1,buf,buf?n:0,NULL,NULL);
-        return len ? len : (size_t)-1;
+        // ToWChar() returns the buffer length, i.e. including the trailing
+        // NUL, while this method doesn't take it into account
+        rc--;
     }
-    
-    bool usable()
-        { return CodePage!=-1; }
 
-public:
-    long CodePage;
-};
-#endif
+    return rc;
+}
 
-class EC_CharSet : public wxCharacterSet
+size_t wxMBConv::WC2MB(char *outBuff, const wchar_t *inBuff, size_t outLen) const
 {
-public:
-    // temporarily just use wxEncodingConverter stuff,
-    // so that it works while a better implementation is built
-    EC_CharSet(const wxChar*name) : wxCharacterSet(name), enc(wxFONTENCODING_SYSTEM)
-    {
-        if (name)
-            enc = wxTheFontMapper->CharsetToEncoding(name, FALSE);
-        m2w.Init(enc, wxFONTENCODING_UNICODE);
-        w2m.Init(wxFONTENCODING_UNICODE, enc);
-    }
-    
-    size_t MB2WC(wchar_t*buf, const char*psz, size_t n)
-    {
-        size_t inbuf = strlen(psz);
-        if (buf) m2w.Convert(psz,buf);
-        return inbuf;
-    }
-    
-    size_t WC2MB(char*buf, const wchar_t*psz, size_t n)
+    size_t rc = FromWChar(outBuff, outLen, inBuff);
+    if ( rc != wxCONV_FAILED )
     {
-#if defined(__BORLANDC__) && (__BORLANDC__ > 0x530)
-        size_t inbuf = std::wcslen(psz);
-#else
-        size_t inbuf = ::wcslen(psz);
-#endif
-        if (buf)
-            w2m.Convert(psz,buf);
-            
-        return inbuf;
+        rc -= GetMBNulLen();
     }
-    
-    bool usable()
-        { return (enc!=wxFONTENCODING_SYSTEM) && (enc!=wxFONTENCODING_DEFAULT); }
 
-public:
-    wxFontEncoding enc;
-    wxEncodingConverter m2w, w2m;
-};
+    return rc;
+}
+
+wxMBConv::~wxMBConv()
+{
+    // nothing to do here (necessary for Darwin linking probably)
+}
 
-static wxCharacterSet *wxGetCharacterSet(const wxChar *name)
+const wxWCharBuffer wxMBConv::cMB2WC(const char *psz) const
 {
-    wxCharacterSet *cset = NULL;
-    if (name)
+    if ( psz )
     {
-        if (!wxStricmp(name, wxT("UTF8")) || !wxStricmp(name, wxT("UTF-8")))
-        {
-            cset = new ID_CharSet(name, &wxConvUTF8);
-        }
-        else
+        // calculate the length of the buffer needed first
+        const size_t nLen = ToWChar(NULL, 0, psz);
+        if ( nLen != wxCONV_FAILED )
         {
-#ifdef HAVE_ICONV_H
-            cset = new IC_CharSet(name); // may not take NULL
-#endif
+            // now do the actual conversion
+            wxWCharBuffer buf(nLen - 1 /* +1 added implicitly */);
+
+            // +1 for the trailing NULL
+            if ( ToWChar(buf.data(), nLen, psz) != wxCONV_FAILED )
+                return buf;
         }
     }
-    
-    if (cset && cset->usable()) return cset;
-    if (cset) delete cset;
-    cset = NULL;
-#ifdef __WIN32__
-    cset = new CP_CharSet(name); // may take NULL
-    if (cset->usable()) return cset;
-#endif
-    if (cset) delete cset;
-    cset = new EC_CharSet(name);
-    if (cset->usable()) return cset;
-    delete cset;
-    wxLogError(_("Unknown encoding '%s'!"), name);
-    return NULL;
-}
 
-wxCSConv::wxCSConv(const wxChar *charset)
-{
-    m_name = (wxChar *) NULL;
-    m_cset = (wxCharacterSet *) NULL;
-    m_deferred = TRUE;
-    SetName(charset);
+    return wxWCharBuffer();
 }
 
-wxCSConv::~wxCSConv()
+const wxCharBuffer wxMBConv::cWC2MB(const wchar_t *pwz) const
 {
-    if (m_name) free(m_name);
-    if (m_cset) delete m_cset;
+    if ( pwz )
+    {
+        const size_t nLen = FromWChar(NULL, 0, pwz);
+        if ( nLen != wxCONV_FAILED )
+        {
+            wxCharBuffer buf(nLen - 1);
+            if ( FromWChar(buf.data(), nLen, pwz) != wxCONV_FAILED )
+                return buf;
+        }
+    }
+
+    return wxCharBuffer();
 }
 
-void wxCSConv::SetName(const wxChar *charset)
+const wxWCharBuffer
+wxMBConv::cMB2WC(const char *inBuff, size_t inLen, size_t *outLen) const
 {
-    if (charset)
+    const size_t dstLen = ToWChar(NULL, 0, inBuff, inLen);
+    if ( dstLen != wxCONV_FAILED )
     {
-        m_name = wxStrdup(charset);
-        m_deferred = TRUE;
+        // notice that we allocate space for dstLen+1 wide characters here
+        // because we want the buffer to always be NUL-terminated, even if the
+        // input isn't (as otherwise the caller has no way to know its length)
+        wxWCharBuffer wbuf(dstLen);
+        wbuf.data()[dstLen] = L'\0';
+        if ( ToWChar(wbuf.data(), dstLen, inBuff, inLen) != wxCONV_FAILED )
+        {
+            if ( outLen )
+            {
+                *outLen = dstLen;
+
+                // we also need to handle NUL-terminated input strings
+                // specially: for them the output is the length of the string
+                // excluding the trailing NUL, however if we're asked to
+                // convert a specific number of characters we return the length
+                // of the resulting output even if it's NUL-terminated
+                if ( inLen == wxNO_LEN )
+                    (*outLen)--;
+            }
+
+            return wbuf;
+        }
     }
+
+    if ( outLen )
+        *outLen = 0;
+
+    return wxWCharBuffer();
 }
 
-void wxCSConv::LoadNow()
+const wxCharBuffer
+wxMBConv::cWC2MB(const wchar_t *inBuff, size_t inLen, size_t *outLen) const
 {
-    if (m_deferred)
+    size_t dstLen = FromWChar(NULL, 0, inBuff, inLen);
+    if ( dstLen != wxCONV_FAILED )
     {
-        if (!m_name)
+        const size_t nulLen = GetMBNulLen();
+
+        // as above, ensure that the buffer is always NUL-terminated, even if
+        // the input is not
+        wxCharBuffer buf(dstLen + nulLen - 1);
+        memset(buf.data() + dstLen, 0, nulLen);
+        if ( FromWChar(buf.data(), dstLen, inBuff, inLen) != wxCONV_FAILED )
         {
-#ifdef __UNIX__
-#if defined(HAVE_LANGINFO_H) && defined(CODESET)
-            // GNU libc provides current character set this way
-            char*alang = nl_langinfo(CODESET);
-            if (alang)
+            if ( outLen )
             {
-                SetName(wxConvLibc.cMB2WX(alang));
+                *outLen = dstLen;
+
+                if ( inLen == wxNO_LEN )
+                {
+                    // in this case both input and output are NUL-terminated
+                    // and we're not supposed to count NUL
+                    *outLen -= nulLen;
+                }
             }
-            else
-#endif
-            {
-                // if we can't get at the character set directly,
-                // try to see if it's in the environment variables
-                // (in most cases this won't work, but I was out of ideas)
-                wxChar *lang = wxGetenv(wxT("LC_ALL"));
-                if (!lang) lang = wxGetenv(wxT("LC_CTYPE"));
-                if (!lang) lang = wxGetenv(wxT("LANG"));
-                wxChar *dot = lang ? wxStrchr(lang, wxT('.')) : (wxChar *)NULL;
-                if (dot) SetName(dot+1);
-            }
-#endif
+
+            return buf;
         }
-        m_cset = wxGetCharacterSet(m_name);
-        m_deferred = FALSE;
     }
+
+    if ( outLen )
+        *outLen = 0;
+
+    return wxCharBuffer();
 }
 
-size_t wxCSConv::MB2WC(wchar_t *buf, const char *psz, size_t n) const
+const wxWCharBuffer wxMBConv::cMB2WC(const wxScopedCharBuffer& buf) const
 {
-    ((wxCSConv *)this)->LoadNow(); // discard constness
-    
-    if (m_cset)
-        return m_cset->MB2WC(buf, psz, n);
-
-    // latin-1 (direct)
-    size_t len=strlen(psz);
-    
-    if (buf)
+    const size_t srcLen = buf.length();
+    if ( srcLen )
     {
-        for (size_t c=0; c<=len; c++)
-            buf[c] = (unsigned char)(psz[c]);
+        const size_t dstLen = ToWChar(NULL, 0, buf, srcLen);
+        if ( dstLen != wxCONV_FAILED )
+        {
+            wxWCharBuffer wbuf(dstLen);
+            wbuf.data()[dstLen] = L'\0';
+            if ( ToWChar(wbuf.data(), dstLen, buf, srcLen) != wxCONV_FAILED )
+                return wbuf;
+        }
     }
-    
-    return len;
+
+    return wxScopedWCharBuffer::CreateNonOwned(L"", 0);
 }
 
-size_t wxCSConv::WC2MB(char *buf, const wchar_t *psz, size_t n) const
+const wxCharBuffer wxMBConv::cWC2MB(const wxScopedWCharBuffer& wbuf) const
 {
-    ((wxCSConv *)this)->LoadNow(); // discard constness
-    
-    if (m_cset)
-        return m_cset->WC2MB(buf, psz, n);
-
-    // latin-1 (direct)
-#if defined(__BORLANDC__) && (__BORLANDC__ > 0x530)
-    size_t len=std::wcslen(psz);
+    const size_t srcLen = wbuf.length();
+    if ( srcLen )
+    {
+        const size_t dstLen = FromWChar(NULL, 0, wbuf, srcLen);
+        if ( dstLen != wxCONV_FAILED )
+        {
+            wxCharBuffer buf(dstLen);
+            buf.data()[dstLen] = '\0';
+            if ( FromWChar(buf.data(), dstLen, wbuf, srcLen) != wxCONV_FAILED )
+                return buf;
+        }
+    }
+
+    return wxScopedCharBuffer::CreateNonOwned("", 0);
+}
+
+// ----------------------------------------------------------------------------
+// wxMBConvLibc
+// ----------------------------------------------------------------------------
+
+size_t wxMBConvLibc::MB2WC(wchar_t *buf, const char *psz, size_t n) const
+{
+    return wxMB2WC(buf, psz, n);
+}
+
+size_t wxMBConvLibc::WC2MB(char *buf, const wchar_t *psz, size_t n) const
+{
+    return wxWC2MB(buf, psz, n);
+}
+
+// ----------------------------------------------------------------------------
+// wxConvBrokenFileNames
+// ----------------------------------------------------------------------------
+
+#ifdef __UNIX__
+
+wxConvBrokenFileNames::wxConvBrokenFileNames(const wxString& charset)
+{
+    if ( wxStricmp(charset, wxT("UTF-8")) == 0 ||
+         wxStricmp(charset, wxT("UTF8")) == 0  )
+        m_conv = new wxMBConvUTF8(wxMBConvUTF8::MAP_INVALID_UTF8_TO_PUA);
+    else
+        m_conv = new wxCSConv(charset);
+}
+
+#endif // __UNIX__
+
+// ----------------------------------------------------------------------------
+// UTF-7
+// ----------------------------------------------------------------------------
+
+// Implementation (C) 2004 Fredrik Roubert
+//
+// Changes to work in streaming mode (C) 2008 Vadim Zeitlin
+
+//
+// BASE64 decoding table
+//
+static const unsigned char utf7unb64[] =
+{
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0x3e, 0xff, 0xff, 0xff, 0x3f,
+    0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b,
+    0x3c, 0x3d, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06,
+    0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e,
+    0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16,
+    0x17, 0x18, 0x19, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20,
+    0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28,
+    0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30,
+    0x31, 0x32, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff
+};
+
+size_t wxMBConvUTF7::ToWChar(wchar_t *dst, size_t dstLen,
+                             const char *src, size_t srcLen) const
+{
+    DecoderState stateOrig,
+                *statePtr;
+    if ( srcLen == wxNO_LEN )
+    {
+        // convert the entire string, up to and including the trailing NUL
+        srcLen = strlen(src) + 1;
+
+        // when working on the entire strings we don't update nor use the shift
+        // state from the previous call
+        statePtr = &stateOrig;
+    }
+    else // when working with partial strings we do use the shift state
+    {
+        statePtr = const_cast<DecoderState *>(&m_stateDecoder);
+
+        // also save the old state to be able to rollback to it on error
+        stateOrig = m_stateDecoder;
+    }
+
+    // but to simplify the code below we use this variable in both cases
+    DecoderState& state = *statePtr;
+
+
+    // number of characters [which would have been] written to dst [if it were
+    // not NULL]
+    size_t len = 0;
+
+    const char * const srcEnd = src + srcLen;
+
+    while ( (src < srcEnd) && (!dst || (len < dstLen)) )
+    {
+        const unsigned char cc = *src++;
+
+        if ( state.IsShifted() )
+        {
+            const unsigned char dc = utf7unb64[cc];
+            if ( dc == 0xff )
+            {
+                // end of encoded part, check that nothing was left: there can
+                // be up to 4 bits of 0 padding but nothing else (we also need
+                // to check isLSB as we count bits modulo 8 while a valid UTF-7
+                // encoded sequence must contain an integral number of UTF-16
+                // characters)
+                if ( state.isLSB || state.bit > 4 ||
+                        (state.accum & ((1 << state.bit) - 1)) )
+                {
+                    if ( !len )
+                        state = stateOrig;
+
+                    return wxCONV_FAILED;
+                }
+
+                state.ToDirect();
+
+                // re-parse this character normally below unless it's '-' which
+                // is consumed by the decoder
+                if ( cc == '-' )
+                    continue;
+            }
+            else // valid encoded character
+            {
+                // mini base64 decoder: each character is 6 bits
+                state.bit += 6;
+                state.accum <<= 6;
+                state.accum += dc;
+
+                if ( state.bit >= 8 )
+                {
+                    // got the full byte, consume it
+                    state.bit -= 8;
+                    unsigned char b = (state.accum >> state.bit) & 0x00ff;
+
+                    if ( state.isLSB )
+                    {
+                        // we've got the full word, output it
+                        if ( dst )
+                            *dst++ = (state.msb << 8) | b;
+                        len++;
+                        state.isLSB = false;
+                    }
+                    else // MSB
+                    {
+                        // just store it while we wait for LSB
+                        state.msb = b;
+                        state.isLSB = true;
+                    }
+                }
+            }
+        }
+
+        if ( state.IsDirect() )
+        {
+            // start of an encoded segment?
+            if ( cc == '+' )
+            {
+                if ( *src == '-' )
+                {
+                    // just the encoded plus sign, don't switch to shifted mode
+                    if ( dst )
+                        *dst++ = '+';
+                    len++;
+                    src++;
+                }
+                else if ( utf7unb64[(unsigned)*src] == 0xff )
+                {
+                    // empty encoded chunks are not allowed
+                    if ( !len )
+                        state = stateOrig;
+
+                    return wxCONV_FAILED;
+                }
+                else // base-64 encoded chunk follows
+                {
+                    state.ToShifted();
+                }
+            }
+            else // not '+'
+            {
+                // only printable 7 bit ASCII characters (with the exception of
+                // NUL, TAB, CR and LF) can be used directly
+                if ( cc >= 0x7f || (cc < ' ' &&
+                      !(cc == '\0' || cc == '\t' || cc == '\r' || cc == '\n')) )
+                    return wxCONV_FAILED;
+
+                if ( dst )
+                    *dst++ = cc;
+                len++;
+            }
+        }
+    }
+
+    if ( !len )
+    {
+        // as we didn't read any characters we should be called with the same
+        // data (followed by some more new data) again later so don't save our
+        // state
+        state = stateOrig;
+
+        return wxCONV_FAILED;
+    }
+
+    return len;
+}
+
+//
+// BASE64 encoding table
+//
+static const unsigned char utf7enb64[] =
+{
+    'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
+    'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
+    'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
+    'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
+    'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
+    'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
+    'w', 'x', 'y', 'z', '0', '1', '2', '3',
+    '4', '5', '6', '7', '8', '9', '+', '/'
+};
+
+//
+// UTF-7 encoding table
+//
+// 0 - Set D (directly encoded characters)
+// 1 - Set O (optional direct characters)
+// 2 - whitespace characters (optional)
+// 3 - special characters
+//
+static const unsigned char utf7encode[128] =
+{
+    0, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 3, 3, 2, 3, 3,
+    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+    2, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 3, 0, 0, 0, 3,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0,
+    1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 3, 1, 1, 1,
+    1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 3, 3
+};
+
+static inline bool wxIsUTF7Direct(wchar_t wc)
+{
+    return wc < 0x80 && utf7encode[wc] < 1;
+}
+
+size_t wxMBConvUTF7::FromWChar(char *dst, size_t dstLen,
+                               const wchar_t *src, size_t srcLen) const
+{
+    EncoderState stateOrig,
+                *statePtr;
+    if ( srcLen == wxNO_LEN )
+    {
+        // we don't apply the stored state when operating on entire strings at
+        // once
+        statePtr = &stateOrig;
+
+        srcLen = wxWcslen(src) + 1;
+    }
+    else // do use the mode we left the output in previously
+    {
+        stateOrig = m_stateEncoder;
+        statePtr = const_cast<EncoderState *>(&m_stateEncoder);
+    }
+
+    EncoderState& state = *statePtr;
+
+
+    size_t len = 0;
+
+    const wchar_t * const srcEnd = src + srcLen;
+    while ( src < srcEnd && (!dst || len < dstLen) )
+    {
+        wchar_t cc = *src++;
+        if ( wxIsUTF7Direct(cc) )
+        {
+            if ( state.IsShifted() )
+            {
+                // pad with zeros the last encoded block if necessary
+                if ( state.bit )
+                {
+                    if ( dst )
+                        *dst++ = utf7enb64[((state.accum % 16) << (6 - state.bit)) % 64];
+                    len++;
+                }
+
+                state.ToDirect();
+
+                if ( dst )
+                    *dst++ = '-';
+                len++;
+            }
+
+            if ( dst )
+                *dst++ = (char)cc;
+            len++;
+        }
+        else if ( cc == '+' && state.IsDirect() )
+        {
+            if ( dst )
+            {
+                *dst++ = '+';
+                *dst++ = '-';
+            }
+
+            len += 2;
+        }
+#ifndef WC_UTF16
+        else if (((wxUint32)cc) > 0xffff)
+        {
+            // no surrogate pair generation (yet?)
+            return wxCONV_FAILED;
+        }
+#endif
+        else
+        {
+            if ( state.IsDirect() )
+            {
+                state.ToShifted();
+
+                if ( dst )
+                    *dst++ = '+';
+                len++;
+            }
+
+            // BASE64 encode string
+            for ( ;; )
+            {
+                for ( unsigned lsb = 0; lsb < 2; lsb++ )
+                {
+                    state.accum <<= 8;
+                    state.accum += lsb ? cc & 0xff : (cc & 0xff00) >> 8;
+
+                    for (state.bit += 8; state.bit >= 6; )
+                    {
+                        state.bit -= 6;
+                        if ( dst )
+                            *dst++ = utf7enb64[(state.accum >> state.bit) % 64];
+                        len++;
+                    }
+                }
+
+                if ( src == srcEnd || wxIsUTF7Direct(cc = *src) )
+                    break;
+
+                src++;
+            }
+        }
+    }
+
+    // we need to restore the original encoder state if we were called just to
+    // calculate the amount of space needed as we will presumably be called
+    // again to really convert the data now
+    if ( !dst )
+        state = stateOrig;
+
+    return len;
+}
+
+// ----------------------------------------------------------------------------
+// UTF-8
+// ----------------------------------------------------------------------------
+
+static const 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;
+
+// this table gives the length of the UTF-8 encoding from its first character:
+const unsigned char tableUtf8Lengths[256] = {
+    // single-byte sequences (ASCII):
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 00..0F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 10..1F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 20..2F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 30..3F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 40..4F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 50..5F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 60..6F
+    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  // 70..7F
+
+    // these are invalid:
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 80..8F
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // 90..9F
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // A0..AF
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,  // B0..BF
+    0, 0,                                            // C0,C1
+
+    // two-byte sequences:
+          2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,  // C2..CF
+    2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,  // D0..DF
+
+    // three-byte sequences:
+    3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,  // E0..EF
+
+    // four-byte sequences:
+    4, 4, 4, 4, 4,                                   // F0..F4
+
+    // these are invalid again (5- or 6-byte
+    // sequences and sequences for code points
+    // above U+10FFFF, as restricted by RFC 3629):
+                   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0   // F5..FF
+};
+
+size_t
+wxMBConvStrictUTF8::ToWChar(wchar_t *dst, size_t dstLen,
+                            const char *src, size_t srcLen) const
+{
+    wchar_t *out = dstLen ? dst : NULL;
+    size_t written = 0;
+
+    if ( srcLen == wxNO_LEN )
+        srcLen = strlen(src) + 1;
+
+    for ( const char *p = src; ; p++ )
+    {
+        if ( (srcLen == wxNO_LEN ? !*p : !srcLen) )
+        {
+            // all done successfully, just add the trailing NULL if we are not
+            // using explicit length
+            if ( srcLen == wxNO_LEN )
+            {
+                if ( out )
+                {
+                    if ( !dstLen )
+                        break;
+
+                    *out = L'\0';
+                }
+
+                written++;
+            }
+
+            return written;
+        }
+
+        if ( out && !dstLen-- )
+            break;
+
+        wxUint32 code;
+        unsigned char c = *p;
+
+        if ( c < 0x80 )
+        {
+            if ( srcLen == 0 ) // the test works for wxNO_LEN too
+                break;
+
+            if ( srcLen != wxNO_LEN )
+                srcLen--;
+
+            code = c;
+        }
+        else
+        {
+            unsigned len = tableUtf8Lengths[c];
+            if ( !len )
+                break;
+
+            if ( srcLen < len ) // the test works for wxNO_LEN too
+                break;
+
+            if ( srcLen != wxNO_LEN )
+                srcLen -= len;
+
+            //   Char. number range   |        UTF-8 octet sequence
+            //      (hexadecimal)     |              (binary)
+            //  ----------------------+----------------------------------------
+            //  0000 0000 - 0000 007F | 0xxxxxxx
+            //  0000 0080 - 0000 07FF | 110xxxxx 10xxxxxx
+            //  0000 0800 - 0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
+            //  0001 0000 - 0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+            //
+            //  Code point value is stored in bits marked with 'x',
+            //  lowest-order bit of the value on the right side in the diagram
+            //  above.                                         (from RFC 3629)
+
+            // mask to extract lead byte's value ('x' bits above), by sequence
+            // length:
+            static const unsigned char leadValueMask[] = { 0x7F, 0x1F, 0x0F, 0x07 };
+
+            // mask and value of lead byte's most significant bits, by length:
+            static const unsigned char leadMarkerMask[] = { 0x80, 0xE0, 0xF0, 0xF8 };
+            static const unsigned char leadMarkerVal[] = { 0x00, 0xC0, 0xE0, 0xF0 };
+
+            len--; // it's more convenient to work with 0-based length here
+
+            // extract the lead byte's value bits:
+            if ( (c & leadMarkerMask[len]) != leadMarkerVal[len] )
+                break;
+
+            code = c & leadValueMask[len];
+
+            // all remaining bytes, if any, are handled in the same way
+            // regardless of sequence's length:
+            for ( ; len; --len )
+            {
+                c = *++p;
+                if ( (c & 0xC0) != 0x80 )
+                    return wxCONV_FAILED;
+
+                code <<= 6;
+                code |= c & 0x3F;
+            }
+        }
+
+#ifdef WC_UTF16
+        // cast is ok because wchar_t == wxUint16 if WC_UTF16
+        if ( encode_utf16(code, (wxUint16 *)out) == 2 )
+        {
+            if ( out )
+                out++;
+            written++;
+        }
+#else // !WC_UTF16
+        if ( out )
+            *out = code;
+#endif // WC_UTF16/!WC_UTF16
+
+        if ( out )
+            out++;
+
+        written++;
+    }
+
+    return wxCONV_FAILED;
+}
+
+size_t
+wxMBConvStrictUTF8::FromWChar(char *dst, size_t dstLen,
+                              const wchar_t *src, size_t srcLen) const
+{
+    char *out = dstLen ? dst : NULL;
+    size_t written = 0;
+
+    for ( const wchar_t *wp = src; ; wp++ )
+    {
+        if ( (srcLen == wxNO_LEN ? !*wp : !srcLen) )
+        {
+            // all done successfully, just add the trailing NULL if we are not
+            // using explicit length
+            if ( srcLen == wxNO_LEN )
+            {
+                if ( out )
+                {
+                    if ( !dstLen )
+                        break;
+
+                    *out = '\0';
+                }
+
+                written++;
+            }
+
+            return written;
+        }
+
+        if ( srcLen != wxNO_LEN )
+            srcLen--;
+
+        wxUint32 code;
+#ifdef WC_UTF16
+        // cast is ok for WC_UTF16
+        if ( decode_utf16((const wxUint16 *)wp, code) == 2 )
+        {
+            // skip the next char too as we decoded a surrogate
+            wp++;
+        }
+#else // wchar_t is UTF-32
+        code = *wp & 0x7fffffff;
+#endif
+
+        unsigned len;
+        if ( code <= 0x7F )
+        {
+            len = 1;
+            if ( out )
+            {
+                if ( dstLen < len )
+                    break;
+
+                out[0] = (char)code;
+            }
+        }
+        else if ( code <= 0x07FF )
+        {
+            len = 2;
+            if ( out )
+            {
+                if ( dstLen < len )
+                    break;
+
+                // NB: this line takes 6 least significant bits, encodes them as
+                // 10xxxxxx and discards them so that the next byte can be encoded:
+                out[1] = 0x80 | (code & 0x3F);  code >>= 6;
+                out[0] = 0xC0 | code;
+            }
+        }
+        else if ( code < 0xFFFF )
+        {
+            len = 3;
+            if ( out )
+            {
+                if ( dstLen < len )
+                    break;
+
+                out[2] = 0x80 | (code & 0x3F);  code >>= 6;
+                out[1] = 0x80 | (code & 0x3F);  code >>= 6;
+                out[0] = 0xE0 | code;
+            }
+        }
+        else if ( code <= 0x10FFFF )
+        {
+            len = 4;
+            if ( out )
+            {
+                if ( dstLen < len )
+                    break;
+
+                out[3] = 0x80 | (code & 0x3F);  code >>= 6;
+                out[2] = 0x80 | (code & 0x3F);  code >>= 6;
+                out[1] = 0x80 | (code & 0x3F);  code >>= 6;
+                out[0] = 0xF0 | code;
+            }
+        }
+        else
+        {
+            wxFAIL_MSG( wxT("trying to encode undefined Unicode character") );
+            break;
+        }
+
+        if ( out )
+        {
+            out += len;
+            dstLen -= len;
+        }
+
+        written += len;
+    }
+
+    // we only get here if an error occurs during decoding
+    return wxCONV_FAILED;
+}
+
+size_t wxMBConvUTF8::ToWChar(wchar_t *buf, size_t n,
+                             const char *psz, size_t srcLen) const
+{
+    if ( m_options == MAP_INVALID_UTF8_NOT )
+        return wxMBConvStrictUTF8::ToWChar(buf, n, psz, srcLen);
+
+    size_t len = 0;
+
+    while ((srcLen == wxNO_LEN ? *psz : srcLen--) && ((!buf) || (len < n)))
+    {
+        const char *opsz = psz;
+        bool invalid = false;
+        unsigned char cc = *psz++, fc = cc;
+        unsigned cnt;
+        for (cnt = 0; fc & 0x80; cnt++)
+            fc <<= 1;
+
+        if (!cnt)
+        {
+            // plain ASCII char
+            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
+        {
+            cnt--;
+            if (!cnt)
+            {
+                // invalid UTF-8 sequence
+                invalid = true;
+            }
+            else
+            {
+                unsigned ocnt = cnt - 1;
+                wxUint32 res = cc & (0x3f >> cnt);
+                while (cnt--)
+                {
+                    cc = *psz;
+                    if ((cc & 0xC0) != 0x80)
+                    {
+                        // invalid UTF-8 sequence
+                        invalid = true;
+                        break;
+                    }
+
+                    psz++;
+                    res = (res << 6) | (cc & 0x3f);
+                }
+
+                if (invalid || res <= utf8_max[ocnt])
+                {
+                    // illegal UTF-8 encoding
+                    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 == wxUint16 if WC_UTF16
+                    size_t pa = encode_utf16(res, (wxUint16 *)buf);
+                    if (pa == wxCONV_FAILED)
+                    {
+                        invalid = true;
+                    }
+                    else
+                    {
+                        if (buf)
+                            buf += pa;
+                        len += pa;
+                    }
+#else // !WC_UTF16
+                    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 != wxCONV_FAILED);
+                        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 wxCONV_FAILED;
+                }
+            }
+        }
+    }
+
+    if (srcLen == wxNO_LEN && buf && (len < n))
+        *buf = 0;
+
+    return len + 1;
+}
+
+static inline bool isoctal(wchar_t wch)
+{
+    return L'0' <= wch && wch <= L'7';
+}
+
+size_t wxMBConvUTF8::FromWChar(char *buf, size_t n,
+                               const wchar_t *psz, size_t srcLen) const
+{
+    if ( m_options == MAP_INVALID_UTF8_NOT )
+        return wxMBConvStrictUTF8::FromWChar(buf, n, psz, srcLen);
+
+    size_t len = 0;
+
+    while ((srcLen == wxNO_LEN ? *psz : srcLen--) && ((!buf) || (len < n)))
+    {
+        wxUint32 cc;
+
+#ifdef WC_UTF16
+        // cast is ok for WC_UTF16
+        size_t pa = decode_utf16((const wxUint16 *)psz, cc);
+        psz += (pa == wxCONV_FAILED) ? 1 : pa;
+#else
+        cc = (*psz++) & 0x7fffffff;
+#endif
+
+        if ( (m_options & MAP_INVALID_UTF8_TO_PUA)
+                && cc >= wxUnicodePUA && cc < wxUnicodePUAEnd )
+        {
+            if (buf)
+                *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
+        {
+            unsigned cnt;
+            for (cnt = 0; cc > utf8_max[cnt]; cnt++)
+            {
+            }
+
+            if (!cnt)
+            {
+                // 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 (srcLen == wxNO_LEN && buf && (len < n))
+        *buf = 0;
+
+    return len + 1;
+}
+
+// ============================================================================
+// UTF-16
+// ============================================================================
+
+#ifdef WORDS_BIGENDIAN
+    #define wxMBConvUTF16straight wxMBConvUTF16BE
+    #define wxMBConvUTF16swap     wxMBConvUTF16LE
+#else
+    #define wxMBConvUTF16swap     wxMBConvUTF16BE
+    #define wxMBConvUTF16straight wxMBConvUTF16LE
+#endif
+
+/* static */
+size_t wxMBConvUTF16Base::GetLength(const char *src, size_t srcLen)
+{
+    if ( srcLen == wxNO_LEN )
+    {
+        // count the number of bytes in input, including the trailing NULs
+        const wxUint16 *inBuff = reinterpret_cast<const wxUint16 *>(src);
+        for ( srcLen = 1; *inBuff++; srcLen++ )
+            ;
+
+        srcLen *= BYTES_PER_CHAR;
+    }
+    else // we already have the length
+    {
+        // we can only convert an entire number of UTF-16 characters
+        if ( srcLen % BYTES_PER_CHAR )
+            return wxCONV_FAILED;
+    }
+
+    return srcLen;
+}
+
+// case when in-memory representation is UTF-16 too
+#ifdef WC_UTF16
+
+// ----------------------------------------------------------------------------
+// conversions without endianness change
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF16straight::ToWChar(wchar_t *dst, size_t dstLen,
+                               const char *src, size_t srcLen) const
+{
+    // set up the scene for using memcpy() (which is presumably more efficient
+    // than copying the bytes one by one)
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    const size_t inLen = srcLen / BYTES_PER_CHAR;
+    if ( dst )
+    {
+        if ( dstLen < inLen )
+            return wxCONV_FAILED;
+
+        memcpy(dst, src, srcLen);
+    }
+
+    return inLen;
+}
+
+size_t
+wxMBConvUTF16straight::FromWChar(char *dst, size_t dstLen,
+                                 const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    srcLen *= BYTES_PER_CHAR;
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        memcpy(dst, src, srcLen);
+    }
+
+    return srcLen;
+}
+
+// ----------------------------------------------------------------------------
+// endian-reversing conversions
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF16swap::ToWChar(wchar_t *dst, size_t dstLen,
+                           const char *src, size_t srcLen) const
+{
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    srcLen /= BYTES_PER_CHAR;
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        const wxUint16 *inBuff = reinterpret_cast<const wxUint16 *>(src);
+        for ( size_t n = 0; n < srcLen; n++, inBuff++ )
+        {
+            *dst++ = wxUINT16_SWAP_ALWAYS(*inBuff);
+        }
+    }
+
+    return srcLen;
+}
+
+size_t
+wxMBConvUTF16swap::FromWChar(char *dst, size_t dstLen,
+                             const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    srcLen *= BYTES_PER_CHAR;
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        wxUint16 *outBuff = reinterpret_cast<wxUint16 *>(dst);
+        for ( size_t n = 0; n < srcLen; n += BYTES_PER_CHAR, src++ )
+        {
+            *outBuff++ = wxUINT16_SWAP_ALWAYS(*src);
+        }
+    }
+
+    return srcLen;
+}
+
+#else // !WC_UTF16: wchar_t is UTF-32
+
+// ----------------------------------------------------------------------------
+// conversions without endianness change
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF16straight::ToWChar(wchar_t *dst, size_t dstLen,
+                               const char *src, size_t srcLen) const
+{
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    const size_t inLen = srcLen / BYTES_PER_CHAR;
+    if ( !dst )
+    {
+        // optimization: return maximal space which could be needed for this
+        // string even if the real size could be smaller if the buffer contains
+        // any surrogates
+        return inLen;
+    }
+
+    size_t outLen = 0;
+    const wxUint16 *inBuff = reinterpret_cast<const wxUint16 *>(src);
+    for ( const wxUint16 * const inEnd = inBuff + inLen; inBuff < inEnd; )
+    {
+        const wxUint32 ch = wxDecodeSurrogate(&inBuff);
+        if ( !inBuff )
+            return wxCONV_FAILED;
+
+        if ( ++outLen > dstLen )
+            return wxCONV_FAILED;
+
+        *dst++ = ch;
+    }
+
+
+    return outLen;
+}
+
+size_t
+wxMBConvUTF16straight::FromWChar(char *dst, size_t dstLen,
+                                 const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    size_t outLen = 0;
+    wxUint16 *outBuff = reinterpret_cast<wxUint16 *>(dst);
+    for ( size_t n = 0; n < srcLen; n++ )
+    {
+        wxUint16 cc[2] = { 0 };
+        const size_t numChars = encode_utf16(*src++, cc);
+        if ( numChars == wxCONV_FAILED )
+            return wxCONV_FAILED;
+
+        outLen += numChars * BYTES_PER_CHAR;
+        if ( outBuff )
+        {
+            if ( outLen > dstLen )
+                return wxCONV_FAILED;
+
+            *outBuff++ = cc[0];
+            if ( numChars == 2 )
+            {
+                // second character of a surrogate
+                *outBuff++ = cc[1];
+            }
+        }
+    }
+
+    return outLen;
+}
+
+// ----------------------------------------------------------------------------
+// endian-reversing conversions
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF16swap::ToWChar(wchar_t *dst, size_t dstLen,
+                           const char *src, size_t srcLen) const
+{
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    const size_t inLen = srcLen / BYTES_PER_CHAR;
+    if ( !dst )
+    {
+        // optimization: return maximal space which could be needed for this
+        // string even if the real size could be smaller if the buffer contains
+        // any surrogates
+        return inLen;
+    }
+
+    size_t outLen = 0;
+    const wxUint16 *inBuff = reinterpret_cast<const wxUint16 *>(src);
+    for ( const wxUint16 * const inEnd = inBuff + inLen; inBuff < inEnd; )
+    {
+        wxUint32 ch;
+        wxUint16 tmp[2];
+
+        tmp[0] = wxUINT16_SWAP_ALWAYS(*inBuff);
+        inBuff++;
+        tmp[1] = wxUINT16_SWAP_ALWAYS(*inBuff);
+
+        const size_t numChars = decode_utf16(tmp, ch);
+        if ( numChars == wxCONV_FAILED )
+            return wxCONV_FAILED;
+
+        if ( numChars == 2 )
+            inBuff++;
+
+        if ( ++outLen > dstLen )
+            return wxCONV_FAILED;
+
+        *dst++ = ch;
+    }
+
+
+    return outLen;
+}
+
+size_t
+wxMBConvUTF16swap::FromWChar(char *dst, size_t dstLen,
+                             const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    size_t outLen = 0;
+    wxUint16 *outBuff = reinterpret_cast<wxUint16 *>(dst);
+    for ( const wchar_t *srcEnd = src + srcLen; src < srcEnd; src++ )
+    {
+        wxUint16 cc[2] = { 0 };
+        const size_t numChars = encode_utf16(*src, cc);
+        if ( numChars == wxCONV_FAILED )
+            return wxCONV_FAILED;
+
+        outLen += numChars * BYTES_PER_CHAR;
+        if ( outBuff )
+        {
+            if ( outLen > dstLen )
+                return wxCONV_FAILED;
+
+            *outBuff++ = wxUINT16_SWAP_ALWAYS(cc[0]);
+            if ( numChars == 2 )
+            {
+                // second character of a surrogate
+                *outBuff++ = wxUINT16_SWAP_ALWAYS(cc[1]);
+            }
+        }
+    }
+
+    return outLen;
+}
+
+#endif // WC_UTF16/!WC_UTF16
+
+
+// ============================================================================
+// UTF-32
+// ============================================================================
+
+#ifdef WORDS_BIGENDIAN
+    #define wxMBConvUTF32straight  wxMBConvUTF32BE
+    #define wxMBConvUTF32swap      wxMBConvUTF32LE
+#else
+    #define wxMBConvUTF32swap      wxMBConvUTF32BE
+    #define wxMBConvUTF32straight  wxMBConvUTF32LE
+#endif
+
+
+WXDLLIMPEXP_DATA_BASE(wxMBConvUTF32LE) wxConvUTF32LE;
+WXDLLIMPEXP_DATA_BASE(wxMBConvUTF32BE) wxConvUTF32BE;
+
+/* static */
+size_t wxMBConvUTF32Base::GetLength(const char *src, size_t srcLen)
+{
+    if ( srcLen == wxNO_LEN )
+    {
+        // count the number of bytes in input, including the trailing NULs
+        const wxUint32 *inBuff = reinterpret_cast<const wxUint32 *>(src);
+        for ( srcLen = 1; *inBuff++; srcLen++ )
+            ;
+
+        srcLen *= BYTES_PER_CHAR;
+    }
+    else // we already have the length
+    {
+        // we can only convert an entire number of UTF-32 characters
+        if ( srcLen % BYTES_PER_CHAR )
+            return wxCONV_FAILED;
+    }
+
+    return srcLen;
+}
+
+// case when in-memory representation is UTF-16
+#ifdef WC_UTF16
+
+// ----------------------------------------------------------------------------
+// conversions without endianness change
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF32straight::ToWChar(wchar_t *dst, size_t dstLen,
+                               const char *src, size_t srcLen) const
+{
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    const wxUint32 *inBuff = reinterpret_cast<const wxUint32 *>(src);
+    const size_t inLen = srcLen / BYTES_PER_CHAR;
+    size_t outLen = 0;
+    for ( size_t n = 0; n < inLen; n++ )
+    {
+        wxUint16 cc[2] = { 0 };
+        const size_t numChars = encode_utf16(*inBuff++, cc);
+        if ( numChars == wxCONV_FAILED )
+            return wxCONV_FAILED;
+
+        outLen += numChars;
+        if ( dst )
+        {
+            if ( outLen > dstLen )
+                return wxCONV_FAILED;
+
+            *dst++ = cc[0];
+            if ( numChars == 2 )
+            {
+                // second character of a surrogate
+                *dst++ = cc[1];
+            }
+        }
+    }
+
+    return outLen;
+}
+
+size_t
+wxMBConvUTF32straight::FromWChar(char *dst, size_t dstLen,
+                                 const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    if ( !dst )
+    {
+        // optimization: return maximal space which could be needed for this
+        // string instead of the exact amount which could be less if there are
+        // any surrogates in the input
+        //
+        // we consider that surrogates are rare enough to make it worthwhile to
+        // avoid running the loop below at the cost of slightly extra memory
+        // consumption
+        return srcLen * BYTES_PER_CHAR;
+    }
+
+    wxUint32 *outBuff = reinterpret_cast<wxUint32 *>(dst);
+    size_t outLen = 0;
+    for ( const wchar_t * const srcEnd = src + srcLen; src < srcEnd; )
+    {
+        const wxUint32 ch = wxDecodeSurrogate(&src);
+        if ( !src )
+            return wxCONV_FAILED;
+
+        outLen += BYTES_PER_CHAR;
+
+        if ( outLen > dstLen )
+            return wxCONV_FAILED;
+
+        *outBuff++ = ch;
+    }
+
+    return outLen;
+}
+
+// ----------------------------------------------------------------------------
+// endian-reversing conversions
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF32swap::ToWChar(wchar_t *dst, size_t dstLen,
+                           const char *src, size_t srcLen) const
+{
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    const wxUint32 *inBuff = reinterpret_cast<const wxUint32 *>(src);
+    const size_t inLen = srcLen / BYTES_PER_CHAR;
+    size_t outLen = 0;
+    for ( size_t n = 0; n < inLen; n++, inBuff++ )
+    {
+        wxUint16 cc[2] = { 0 };
+        const size_t numChars = encode_utf16(wxUINT32_SWAP_ALWAYS(*inBuff), cc);
+        if ( numChars == wxCONV_FAILED )
+            return wxCONV_FAILED;
+
+        outLen += numChars;
+        if ( dst )
+        {
+            if ( outLen > dstLen )
+                return wxCONV_FAILED;
+
+            *dst++ = cc[0];
+            if ( numChars == 2 )
+            {
+                // second character of a surrogate
+                *dst++ = cc[1];
+            }
+        }
+    }
+
+    return outLen;
+}
+
+size_t
+wxMBConvUTF32swap::FromWChar(char *dst, size_t dstLen,
+                             const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    if ( !dst )
+    {
+        // optimization: return maximal space which could be needed for this
+        // string instead of the exact amount which could be less if there are
+        // any surrogates in the input
+        //
+        // we consider that surrogates are rare enough to make it worthwhile to
+        // avoid running the loop below at the cost of slightly extra memory
+        // consumption
+        return srcLen*BYTES_PER_CHAR;
+    }
+
+    wxUint32 *outBuff = reinterpret_cast<wxUint32 *>(dst);
+    size_t outLen = 0;
+    for ( const wchar_t * const srcEnd = src + srcLen; src < srcEnd; )
+    {
+        const wxUint32 ch = wxDecodeSurrogate(&src);
+        if ( !src )
+            return wxCONV_FAILED;
+
+        outLen += BYTES_PER_CHAR;
+
+        if ( outLen > dstLen )
+            return wxCONV_FAILED;
+
+        *outBuff++ = wxUINT32_SWAP_ALWAYS(ch);
+    }
+
+    return outLen;
+}
+
+#else // !WC_UTF16: wchar_t is UTF-32
+
+// ----------------------------------------------------------------------------
+// conversions without endianness change
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF32straight::ToWChar(wchar_t *dst, size_t dstLen,
+                               const char *src, size_t srcLen) const
+{
+    // use memcpy() as it should be much faster than hand-written loop
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    const size_t inLen = srcLen/BYTES_PER_CHAR;
+    if ( dst )
+    {
+        if ( dstLen < inLen )
+            return wxCONV_FAILED;
+
+        memcpy(dst, src, srcLen);
+    }
+
+    return inLen;
+}
+
+size_t
+wxMBConvUTF32straight::FromWChar(char *dst, size_t dstLen,
+                                 const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    srcLen *= BYTES_PER_CHAR;
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        memcpy(dst, src, srcLen);
+    }
+
+    return srcLen;
+}
+
+// ----------------------------------------------------------------------------
+// endian-reversing conversions
+// ----------------------------------------------------------------------------
+
+size_t
+wxMBConvUTF32swap::ToWChar(wchar_t *dst, size_t dstLen,
+                           const char *src, size_t srcLen) const
+{
+    srcLen = GetLength(src, srcLen);
+    if ( srcLen == wxNO_LEN )
+        return wxCONV_FAILED;
+
+    srcLen /= BYTES_PER_CHAR;
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        const wxUint32 *inBuff = reinterpret_cast<const wxUint32 *>(src);
+        for ( size_t n = 0; n < srcLen; n++, inBuff++ )
+        {
+            *dst++ = wxUINT32_SWAP_ALWAYS(*inBuff);
+        }
+    }
+
+    return srcLen;
+}
+
+size_t
+wxMBConvUTF32swap::FromWChar(char *dst, size_t dstLen,
+                             const wchar_t *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    srcLen *= BYTES_PER_CHAR;
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        wxUint32 *outBuff = reinterpret_cast<wxUint32 *>(dst);
+        for ( size_t n = 0; n < srcLen; n += BYTES_PER_CHAR, src++ )
+        {
+            *outBuff++ = wxUINT32_SWAP_ALWAYS(*src);
+        }
+    }
+
+    return srcLen;
+}
+
+#endif // WC_UTF16/!WC_UTF16
+
+
+// ============================================================================
+// The classes doing conversion using the iconv_xxx() functions
+// ============================================================================
+
+#ifdef HAVE_ICONV
+
+// VS: glibc 2.1.3 is broken in that iconv() conversion to/from UCS4 fails with
+//     E2BIG if output buffer is _exactly_ as big as needed. Such case is
+//     (unless there's yet another bug in glibc) the only case when iconv()
+//     returns with (size_t)-1 (which means error) and says there are 0 bytes
+//     left in the input buffer -- when _real_ error occurs,
+//     bytes-left-in-input buffer is non-zero. Hence, this alternative test for
+//     iconv() failure.
+//     [This bug does not appear in glibc 2.2.]
+#if defined(__GLIBC__) && __GLIBC__ == 2 && __GLIBC_MINOR__ <= 1
+#define ICONV_FAILED(cres, bufLeft) ((cres == (size_t)-1) && \
+                                     (errno != E2BIG || bufLeft != 0))
 #else
-    size_t len=::wcslen(psz);
+#define ICONV_FAILED(cres, bufLeft)  (cres == (size_t)-1)
+#endif
+
+#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
+// ----------------------------------------------------------------------------
+
+class wxMBConv_iconv : public wxMBConv
+{
+public:
+    wxMBConv_iconv(const char *name);
+    virtual ~wxMBConv_iconv();
+
+    // implement base class virtual methods
+    virtual size_t ToWChar(wchar_t *dst, size_t dstLen,
+                           const char *src, size_t srcLen = wxNO_LEN) const;
+    virtual size_t FromWChar(char *dst, size_t dstLen,
+                             const wchar_t *src, size_t srcLen = wxNO_LEN) const;
+    virtual size_t GetMBNulLen() const;
+
+#if wxUSE_UNICODE_UTF8
+    virtual bool IsUTF8() const;
+#endif
+
+    virtual wxMBConv *Clone() const
+    {
+        wxMBConv_iconv *p = new wxMBConv_iconv(m_name);
+        p->m_minMBCharWidth = m_minMBCharWidth;
+        return p;
+    }
+
+    bool IsOk() const
+        { return (m2w != ICONV_T_INVALID) && (w2m != ICONV_T_INVALID); }
+
+protected:
+    // the iconv handlers used to translate from multibyte
+    // to wide char and in the other direction
+    iconv_t m2w,
+            w2m;
+
+#if wxUSE_THREADS
+    // guards access to m2w and w2m objects
+    wxMutex m_iconvMutex;
+#endif
+
+private:
+    // the name (for iconv_open()) of a wide char charset -- if none is
+    // available on this machine, it will remain NULL
+    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;
+
+
+    // name of the encoding handled by this conversion
+    const char *m_name;
+
+    // cached result of GetMBNulLen(); set to 0 meaning "unknown"
+    // initially
+    size_t m_minMBCharWidth;
+};
+
+// make the constructor available for unit testing
+WXDLLIMPEXP_BASE wxMBConv* new_wxMBConv_iconv( const char* 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 char *name)
+              : m_name(wxStrdup(name))
+{
+    m_minMBCharWidth = 0;
+
+    // check for charset that represents wchar_t:
+    if ( ms_wcCharsetName.empty() )
+    {
+        wxLogTrace(TRACE_STRCONV, wxT("Looking for wide char codeset:"));
+
+#if wxUSE_FONTMAP
+        const wxChar *const *names = wxFontMapperBase::GetAllEncodingNames(WC_ENC);
+#else // !wxUSE_FONTMAP
+        static const wxChar *const names_static[] =
+        {
+#if SIZEOF_WCHAR_T == 4
+            wxT("UCS-4"),
+#elif SIZEOF_WCHAR_T == 2
+            wxT("UCS-2"),
+#endif
+            NULL
+        };
+        const wxChar *const *names = names_static;
+#endif // wxUSE_FONTMAP/!wxUSE_FONTMAP
+
+        for ( ; *names && ms_wcCharsetName.empty(); ++names )
+        {
+            const wxString nameCS(*names);
+
+            // first try charset with explicit bytesex info (e.g. "UCS-4LE"):
+            wxString nameXE(nameCS);
+
+#ifdef WORDS_BIGENDIAN
+                nameXE += wxT("BE");
+#else // little endian
+                nameXE += wxT("LE");
+#endif
+
+            wxLogTrace(TRACE_STRCONV, wxT("  trying charset \"%s\""),
+                       nameXE.c_str());
+
+            m2w = iconv_open(nameXE.ToAscii(), name);
+            if ( m2w == ICONV_T_INVALID )
+            {
+                // try charset w/o bytesex info (e.g. "UCS4")
+                wxLogTrace(TRACE_STRCONV, wxT("  trying charset \"%s\""),
+                           nameCS.c_str());
+                m2w = iconv_open(nameCS.ToAscii(), name);
+
+                // and check for bytesex ourselves:
+                if ( m2w != ICONV_T_INVALID )
+                {
+                    char    buf[2], *bufPtr;
+                    wchar_t wbuf[2];
+                    size_t  insz, outsz;
+                    size_t  res;
+
+                    buf[0] = 'A';
+                    buf[1] = 0;
+                    wbuf[0] = 0;
+                    insz = 2;
+                    outsz = SIZEOF_WCHAR_T * 2;
+                    char* wbufPtr = (char*)wbuf;
+                    bufPtr = buf;
+
+                    res = iconv(
+                        m2w, ICONV_CHAR_CAST(&bufPtr), &insz,
+                        &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 // use charset not requiring byte swapping
+            {
+                ms_wcCharsetName = nameXE;
+            }
+        }
+
+        wxLogTrace(TRACE_STRCONV,
+                   wxT("iconv wchar_t charset is \"%s\"%s"),
+                   ms_wcCharsetName.empty() ? wxString("<none>")
+                                            : ms_wcCharsetName,
+                   ms_wcNeedsSwap ? wxT(" (needs swap)")
+                                  : wxT(""));
+    }
+    else // we already have ms_wcCharsetName
+    {
+        m2w = iconv_open(ms_wcCharsetName.ToAscii(), name);
+    }
+
+    if ( ms_wcCharsetName.empty() )
+    {
+        w2m = ICONV_T_INVALID;
+    }
+    else
+    {
+        w2m = iconv_open(name, ms_wcCharsetName.ToAscii());
+        if ( w2m == ICONV_T_INVALID )
+        {
+            wxLogTrace(TRACE_STRCONV,
+                       wxT("\"%s\" -> \"%s\" works but not the converse!?"),
+                       ms_wcCharsetName.c_str(), name);
+        }
+    }
+}
+
+wxMBConv_iconv::~wxMBConv_iconv()
+{
+    free(const_cast<char *>(m_name));
+
+    if ( m2w != ICONV_T_INVALID )
+        iconv_close(m2w);
+    if ( w2m != ICONV_T_INVALID )
+        iconv_close(w2m);
+}
+
+size_t
+wxMBConv_iconv::ToWChar(wchar_t *dst, size_t dstLen,
+                        const char *src, size_t srcLen) const
+{
+    if ( srcLen == wxNO_LEN )
+    {
+        // find the string length: notice that must be done differently for
+        // NUL-terminated strings and UTF-16/32 which are terminated with 2/4
+        // consecutive NULs
+        const size_t nulLen = GetMBNulLen();
+        switch ( nulLen )
+        {
+            default:
+                return wxCONV_FAILED;
+
+            case 1:
+                srcLen = strlen(src); // arguably more optimized than our version
+                break;
+
+            case 2:
+            case 4:
+                // for UTF-16/32 not only we need to have 2/4 consecutive NULs
+                // but they also have to start at character boundary and not
+                // span two adjacent characters
+                const char *p;
+                for ( p = src; NotAllNULs(p, nulLen); p += nulLen )
+                    ;
+                srcLen = p - src;
+                break;
+        }
+
+        // when we're determining the length of the string ourselves we count
+        // the terminating NUL(s) as part of it and always NUL-terminate the
+        // output
+        srcLen += nulLen;
+    }
+
+    // we express length in the number of (wide) characters but iconv always
+    // counts buffer sizes it in bytes
+    dstLen *= SIZEOF_WCHAR_T;
+
+#if wxUSE_THREADS
+    // NB: iconv() is MT-safe, but each thread must use its own iconv_t handle.
+    //     Unfortunately there are a couple of global wxCSConv objects such as
+    //     wxConvLocal that are used all over wx code, so we have to make sure
+    //     the handle is used by at most one thread at the time. Otherwise
+    //     only a few wx classes would be safe to use from non-main threads
+    //     as MB<->WC conversion would fail "randomly".
+    wxMutexLocker lock(wxConstCast(this, wxMBConv_iconv)->m_iconvMutex);
+#endif // wxUSE_THREADS
+
+    size_t res, cres;
+    const char *pszPtr = src;
+
+    if ( dst )
+    {
+        char* bufPtr = (char*)dst;
+
+        // have destination buffer, convert there
+        size_t dstLenOrig = dstLen;
+        cres = iconv(m2w,
+                     ICONV_CHAR_CAST(&pszPtr), &srcLen,
+                     &bufPtr, &dstLen);
+
+        // convert the number of bytes converted as returned by iconv to the
+        // number of (wide) characters converted that we need
+        res = (dstLenOrig - dstLen) / SIZEOF_WCHAR_T;
+
+        if (ms_wcNeedsSwap)
+        {
+            // convert to native endianness
+            for ( unsigned i = 0; i < res; i++ )
+                dst[i] = WC_BSWAP(dst[i]);
+        }
+    }
+    else // no destination buffer
+    {
+        // convert using temp buffer to calculate the size of the buffer needed
+        wchar_t tbuf[256];
+        res = 0;
+
+        do
+        {
+            char* bufPtr = (char*)tbuf;
+            dstLen = 8 * SIZEOF_WCHAR_T;
+
+            cres = iconv(m2w,
+                         ICONV_CHAR_CAST(&pszPtr), &srcLen,
+                         &bufPtr, &dstLen );
+
+            res += 8 - (dstLen / SIZEOF_WCHAR_T);
+        }
+        while ((cres == (size_t)-1) && (errno == E2BIG));
+    }
+
+    if (ICONV_FAILED(cres, srcLen))
+    {
+        //VS: it is ok if iconv fails, hence trace only
+        wxLogTrace(TRACE_STRCONV, wxT("iconv failed: %s"), wxSysErrorMsg(wxSysErrorCode()));
+        return wxCONV_FAILED;
+    }
+
+    return res;
+}
+
+size_t wxMBConv_iconv::FromWChar(char *dst, size_t dstLen,
+                                 const wchar_t *src, size_t srcLen) const
+{
+#if wxUSE_THREADS
+    // NB: explained in MB2WC
+    wxMutexLocker lock(wxConstCast(this, wxMBConv_iconv)->m_iconvMutex);
+#endif
+
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    size_t inbuflen = srcLen * SIZEOF_WCHAR_T;
+    size_t outbuflen = dstLen;
+    size_t res, cres;
+
+    wchar_t *tmpbuf = 0;
+
+    if (ms_wcNeedsSwap)
+    {
+        // need to copy to temp buffer to switch endianness
+        // (doing WC_BSWAP twice on the original buffer won't work, as it
+        //  could be in read-only memory, or be accessed in some other thread)
+        tmpbuf = (wchar_t *)malloc(inbuflen);
+        for ( size_t i = 0; i < srcLen; i++ )
+            tmpbuf[i] = WC_BSWAP(src[i]);
+
+        src = tmpbuf;
+    }
+
+    char* inbuf = (char*)src;
+    if ( dst )
+    {
+        // have destination buffer, convert there
+        cres = iconv(w2m, ICONV_CHAR_CAST(&inbuf), &inbuflen, &dst, &outbuflen);
+
+        res = dstLen - outbuflen;
+    }
+    else // no destination buffer
+    {
+        // convert using temp buffer to calculate the size of the buffer needed
+        char tbuf[256];
+        res = 0;
+        do
+        {
+            dst = tbuf;
+            outbuflen = WXSIZEOF(tbuf);
+
+            cres = iconv(w2m, ICONV_CHAR_CAST(&inbuf), &inbuflen, &dst, &outbuflen);
+
+            res += WXSIZEOF(tbuf) - outbuflen;
+        }
+        while ((cres == (size_t)-1) && (errno == E2BIG));
+    }
+
+    if (ms_wcNeedsSwap)
+    {
+        free(tmpbuf);
+    }
+
+    if (ICONV_FAILED(cres, inbuflen))
+    {
+        wxLogTrace(TRACE_STRCONV, wxT("iconv failed: %s"), wxSysErrorMsg(wxSysErrorCode()));
+        return wxCONV_FAILED;
+    }
+
+    return res;
+}
+
+size_t wxMBConv_iconv::GetMBNulLen() const
+{
+    if ( m_minMBCharWidth == 0 )
+    {
+        wxMBConv_iconv * const self = wxConstCast(this, wxMBConv_iconv);
+
+#if wxUSE_THREADS
+        // NB: explained in MB2WC
+        wxMutexLocker lock(self->m_iconvMutex);
+#endif
+
+        const wchar_t *wnul = L"";
+        char buf[8]; // should be enough for NUL in any encoding
+        size_t inLen = sizeof(wchar_t),
+               outLen = WXSIZEOF(buf);
+        char *inBuff = (char *)wnul;
+        char *outBuff = buf;
+        if ( iconv(w2m, ICONV_CHAR_CAST(&inBuff), &inLen, &outBuff, &outLen) == (size_t)-1 )
+        {
+            self->m_minMBCharWidth = (size_t)-1;
+        }
+        else // ok
+        {
+            self->m_minMBCharWidth = outBuff - buf;
+        }
+    }
+
+    return m_minMBCharWidth;
+}
+
+#if wxUSE_UNICODE_UTF8
+bool wxMBConv_iconv::IsUTF8() const
+{
+    return wxStricmp(m_name, "UTF-8") == 0 ||
+           wxStricmp(m_name, "UTF8") == 0;
+}
+#endif
+
+#endif // HAVE_ICONV
+
+
+// ============================================================================
+// Win32 conversion classes
+// ============================================================================
+
+#ifdef wxHAVE_WIN32_MB2WC
+
+// from utils.cpp
+#if wxUSE_FONTMAP
+extern WXDLLIMPEXP_BASE long wxCharsetToCodepage(const char *charset);
+extern WXDLLIMPEXP_BASE long wxEncodingToCodepage(wxFontEncoding encoding);
 #endif
-    if (buf)
+
+class wxMBConv_win32 : public wxMBConv
+{
+public:
+    wxMBConv_win32()
+    {
+        m_CodePage = CP_ACP;
+        m_minMBCharWidth = 0;
+    }
+
+    wxMBConv_win32(const wxMBConv_win32& conv)
+        : wxMBConv()
+    {
+        m_CodePage = conv.m_CodePage;
+        m_minMBCharWidth = conv.m_minMBCharWidth;
+    }
+
+#if wxUSE_FONTMAP
+    wxMBConv_win32(const char* name)
+    {
+        m_CodePage = wxCharsetToCodepage(name);
+        m_minMBCharWidth = 0;
+    }
+
+    wxMBConv_win32(wxFontEncoding encoding)
+    {
+        m_CodePage = wxEncodingToCodepage(encoding);
+        m_minMBCharWidth = 0;
+    }
+#endif // wxUSE_FONTMAP
+
+    virtual size_t MB2WC(wchar_t *buf, const char *psz, size_t n) const
+    {
+        // note that we have to use MB_ERR_INVALID_CHARS flag as it without it
+        // the behaviour is not compatible with the Unix version (using iconv)
+        // and break the library itself, e.g. wxTextInputStream::NextChar()
+        // wouldn't work if reading an incomplete MB char didn't result in an
+        // error
+        //
+        // Moreover, MB_ERR_INVALID_CHARS is only supported on Win 2K SP4 or
+        // Win XP or newer and it is not supported for UTF-[78] so we always
+        // use our own conversions in this case. See
+        //     http://blogs.msdn.com/michkap/archive/2005/04/19/409566.aspx
+        //     http://msdn.microsoft.com/library/en-us/intl/unicode_17si.asp
+        if ( m_CodePage == CP_UTF8 )
+        {
+            return wxMBConvUTF8().MB2WC(buf, psz, n);
+        }
+
+        if ( m_CodePage == CP_UTF7 )
+        {
+            return wxMBConvUTF7().MB2WC(buf, psz, n);
+        }
+
+        int flags = 0;
+        if ( (m_CodePage < 50000 && m_CodePage != CP_SYMBOL) &&
+                IsAtLeastWin2kSP4() )
+        {
+            flags = MB_ERR_INVALID_CHARS;
+        }
+
+        const size_t len = ::MultiByteToWideChar
+                             (
+                                m_CodePage,     // code page
+                                flags,          // flags: fall on error
+                                psz,            // input string
+                                -1,             // its length (NUL-terminated)
+                                buf,            // output string
+                                buf ? n : 0     // size of output buffer
+                             );
+        if ( !len )
+        {
+            // function totally failed
+            return wxCONV_FAILED;
+        }
+
+        // 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 wxCONV_FAILED;
+            }
+        }
+
+        // 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 - 1;
+    }
+
+    virtual size_t WC2MB(char *buf, const wchar_t *pwz, size_t n) const
+    {
+        /*
+            we have a problem here: by default, WideCharToMultiByte() may
+            replace characters unrepresentable in the target code page with bad
+            quality approximations such as turning "1/2" symbol (U+00BD) into
+            "1" for the code pages which don't have it and we, obviously, want
+            to avoid this at any price
+
+            the trouble is that this function does it _silently_, i.e. it won't
+            even tell us whether it did or not... Win98/2000 and higher provide
+            WC_NO_BEST_FIT_CHARS but it doesn't work for the older systems and
+            we have to resort to a round trip, i.e. check that converting back
+            results in the same string -- this is, of course, expensive but
+            otherwise we simply can't be sure to not garble the data.
+         */
+
+        // determine if we can rely on WC_NO_BEST_FIT_CHARS: according to MSDN
+        // it doesn't work with CJK encodings (which we test for rather roughly
+        // here...) nor with UTF-7/8 nor, of course, with Windows versions not
+        // supporting it
+        BOOL usedDef wxDUMMY_INITIALIZE(false);
+        BOOL *pUsedDef;
+        int flags;
+        if ( CanUseNoBestFit() && m_CodePage < 50000 )
+        {
+            // it's our lucky day
+            flags = WC_NO_BEST_FIT_CHARS;
+            pUsedDef = &usedDef;
+        }
+        else // old system or unsupported encoding
+        {
+            flags = 0;
+            pUsedDef = NULL;
+        }
+
+        const size_t len = ::WideCharToMultiByte
+                             (
+                                m_CodePage,     // code page
+                                flags,          // either none or no best fit
+                                pwz,            // input string
+                                -1,             // it is (wide) NUL-terminated
+                                buf,            // output buffer
+                                buf ? n : 0,    // and its size
+                                NULL,           // default "replacement" char
+                                pUsedDef        // [out] was it used?
+                             );
+
+        if ( !len )
+        {
+            // function totally failed
+            return wxCONV_FAILED;
+        }
+
+        // we did something, check if we really succeeded
+        if ( flags )
+        {
+            // check if the conversion failed, i.e. if any replacements
+            // were done
+            if ( usedDef )
+                return wxCONV_FAILED;
+        }
+        else // we must resort to double tripping...
+        {
+            // first we need to ensure that we really have the MB data: this is
+            // not the case if we're called with NULL buffer, in which case we
+            // need to do the conversion yet again
+            wxCharBuffer bufDef;
+            if ( !buf )
+            {
+                bufDef = wxCharBuffer(len);
+                buf = bufDef.data();
+                if ( !::WideCharToMultiByte(m_CodePage, flags, pwz, -1,
+                                            buf, len, NULL, NULL) )
+                    return wxCONV_FAILED;
+            }
+
+            if ( !n )
+                n = wcslen(pwz);
+            wxWCharBuffer wcBuf(n);
+            if ( MB2WC(wcBuf.data(), buf, n + 1) == wxCONV_FAILED ||
+                    wcscmp(wcBuf, pwz) != 0 )
+            {
+                // we didn't obtain the same thing we started from, hence
+                // the conversion was lossy and we consider that it failed
+                return wxCONV_FAILED;
+            }
+        }
+
+        // see the comment above for the reason of "len - 1"
+        return len - 1;
+    }
+
+    virtual size_t GetMBNulLen() const
+    {
+        if ( m_minMBCharWidth == 0 )
+        {
+            int len = ::WideCharToMultiByte
+                        (
+                            m_CodePage,     // code page
+                            0,              // no flags
+                            L"",            // input string
+                            1,              // translate just the NUL
+                            NULL,           // output buffer
+                            0,              // and its size
+                            NULL,           // no replacement char
+                            NULL            // [out] don't care if it was used
+                        );
+
+            wxMBConv_win32 * const self = wxConstCast(this, wxMBConv_win32);
+            switch ( len )
+            {
+                default:
+                    wxLogDebug(wxT("Unexpected NUL length %d"), len);
+                    self->m_minMBCharWidth = (size_t)-1;
+                    break;
+
+                case 0:
+                    self->m_minMBCharWidth = (size_t)-1;
+                    break;
+
+                case 1:
+                case 2:
+                case 4:
+                    self->m_minMBCharWidth = len;
+                    break;
+            }
+        }
+
+        return m_minMBCharWidth;
+    }
+
+    virtual wxMBConv *Clone() const { return new wxMBConv_win32(*this); }
+
+    bool IsOk() const { return m_CodePage != -1; }
+
+private:
+    static bool CanUseNoBestFit()
     {
-        for (size_t c=0; c<=len; c++)
-            buf[c] = (psz[c]>0xff) ? '?' : psz[c];
+        static int s_isWin98Or2k = -1;
+
+        if ( s_isWin98Or2k == -1 )
+        {
+            int verMaj, verMin;
+            switch ( wxGetOsVersion(&verMaj, &verMin) )
+            {
+                case wxOS_WINDOWS_9X:
+                    s_isWin98Or2k = verMaj >= 4 && verMin >= 10;
+                    break;
+
+                case wxOS_WINDOWS_NT:
+                    s_isWin98Or2k = verMaj >= 5;
+                    break;
+
+                default:
+                    // unknown: be conservative by default
+                    s_isWin98Or2k = 0;
+                    break;
+            }
+
+            wxASSERT_MSG( s_isWin98Or2k != -1, wxT("should be set above") );
+        }
+
+        return s_isWin98Or2k == 1;
     }
-    
-    return len;
-}
 
-#ifdef HAVE_ICONV_H
-class IC_CharSetConverter
-{
-public:
-    IC_CharSetConverter(IC_CharSet*from,IC_CharSet*to)
-        { cnv = iconv_open(wxConvLibc.cWX2MB(to->cname),wxConvLibc.cWX2MB(from->cname)); }
-        
-    ~IC_CharSetConverter()
-        { if (cnv!=(iconv_t)-1) iconv_close(cnv); }
-        
-    size_t Convert(char*buf, const char*psz, size_t n)
+    static bool IsAtLeastWin2kSP4()
     {
-        size_t inbuf = strlen(psz);
-        size_t outbuf = n;
-#ifdef WX_ICONV_TAKES_CHAR
-        size_t res = iconv( cnv, (char**)&psz, &inbuf, &buf, &outbuf );
+#ifdef __WXWINCE__
+        return false;
 #else
-        size_t res = iconv( cnv, &psz, &inbuf, &buf, &outbuf );
+        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
-        if (res==(size_t)-1) return (size_t)-1;
-        return n-outbuf;
     }
 
-public:
-    iconv_t cnv;
+
+    // the code page we're working with
+    long m_CodePage;
+
+    // cached result of GetMBNulLen(), set to 0 initially meaning
+    // "unknown"
+    size_t m_minMBCharWidth;
 };
-#endif
 
-class EC_CharSetConverter
+#endif // wxHAVE_WIN32_MB2WC
+
+
+// ============================================================================
+// wxEncodingConverter based conversion classes
+// ============================================================================
+
+#if wxUSE_FONTMAP
+
+class wxMBConv_wxwin : public wxMBConv
 {
+private:
+    void Init()
+    {
+        // Refuse to use broken wxEncodingConverter code for Mac-specific encodings.
+        // The wxMBConv_cf class does a better job.
+        m_ok = (m_enc < wxFONTENCODING_MACMIN || m_enc > wxFONTENCODING_MACMAX) &&
+               m2w.Init(m_enc, wxFONTENCODING_UNICODE) &&
+               w2m.Init(wxFONTENCODING_UNICODE, m_enc);
+    }
+
 public:
-    EC_CharSetConverter(EC_CharSet*from,EC_CharSet*to)
-        { cnv.Init(from->enc,to->enc); }
-        
-    size_t Convert(char*buf, const char*psz, size_t n)
+    // temporarily just use wxEncodingConverter stuff,
+    // so that it works while a better implementation is built
+    wxMBConv_wxwin(const char* name)
+    {
+        if (name)
+            m_enc = wxFontMapperBase::Get()->CharsetToEncoding(name, false);
+        else
+            m_enc = wxFONTENCODING_SYSTEM;
+
+        Init();
+    }
+
+    wxMBConv_wxwin(wxFontEncoding enc)
+    {
+        m_enc = enc;
+
+        Init();
+    }
+
+    size_t MB2WC(wchar_t *buf, const char *psz, size_t WXUNUSED(n)) const
     {
         size_t inbuf = strlen(psz);
-        if (buf) cnv.Convert(psz,buf);
+        if (buf)
+        {
+            if (!m2w.Convert(psz, buf))
+                return wxCONV_FAILED;
+        }
+        return inbuf;
+    }
+
+    size_t WC2MB(char *buf, const wchar_t *psz, size_t WXUNUSED(n)) const
+    {
+        const size_t inbuf = wxWcslen(psz);
+        if (buf)
+        {
+            if (!w2m.Convert(psz, buf))
+                return wxCONV_FAILED;
+        }
+
         return inbuf;
     }
-  
+
+    virtual size_t GetMBNulLen() const
+    {
+        switch ( m_enc )
+        {
+            case wxFONTENCODING_UTF16BE:
+            case wxFONTENCODING_UTF16LE:
+                return 2;
+
+            case wxFONTENCODING_UTF32BE:
+            case wxFONTENCODING_UTF32LE:
+                return 4;
+
+            default:
+                return 1;
+        }
+    }
+
+    virtual wxMBConv *Clone() const { return new wxMBConv_wxwin(m_enc); }
+
+    bool IsOk() const { return m_ok; }
+
 public:
-    wxEncodingConverter cnv;
+    wxFontEncoding m_enc;
+    wxEncodingConverter m2w, w2m;
+
+private:
+    // were we initialized successfully?
+    bool m_ok;
+
+    wxDECLARE_NO_COPY_CLASS(wxMBConv_wxwin);
 };
 
-#else // !wxUSE_WCHAR_T
+// make the constructors available for unit testing
+WXDLLIMPEXP_BASE wxMBConv* new_wxMBConv_wxwin( const char* name )
+{
+    wxMBConv_wxwin* result = new wxMBConv_wxwin( name );
+    if ( !result->IsOk() )
+    {
+        delete result;
+        return 0;
+    }
+
+    return result;
+}
+
+#endif // wxUSE_FONTMAP
+
+// ============================================================================
+// wxCSConv implementation
+// ============================================================================
+
+void wxCSConv::Init()
+{
+    m_name = NULL;
+    m_convReal =  NULL;
+}
+
+void wxCSConv::SetEncoding(wxFontEncoding encoding)
+{
+    switch ( encoding )
+    {
+        case wxFONTENCODING_MAX:
+        case wxFONTENCODING_SYSTEM:
+            if ( m_name )
+            {
+                // It's ok to not have encoding value if we have a name for it.
+                m_encoding = wxFONTENCODING_SYSTEM;
+            }
+            else // No name neither.
+            {
+                // Fall back to the system default encoding in this case (not
+                // sure how much sense does this make but this is how the old
+                // code used to behave).
+#if wxUSE_INTL
+                m_encoding = wxLocale::GetSystemEncoding();
+                if ( m_encoding == wxFONTENCODING_SYSTEM )
+#endif // wxUSE_INTL
+                    m_encoding = wxFONTENCODING_ISO8859_1;
+            }
+            break;
+
+        case wxFONTENCODING_DEFAULT:
+            // wxFONTENCODING_DEFAULT is same as US-ASCII in this context
+            m_encoding = wxFONTENCODING_ISO8859_1;
+            break;
+
+        default:
+            // Just use the provided encoding.
+            m_encoding = encoding;
+    }
+}
+
+wxCSConv::wxCSConv(const wxString& charset)
+{
+    Init();
+
+    if ( !charset.empty() )
+    {
+        SetName(charset.ToAscii());
+    }
+
+#if wxUSE_FONTMAP
+    SetEncoding(wxFontMapperBase::GetEncodingFromName(charset));
+#else
+    SetEncoding(wxFONTENCODING_SYSTEM);
+#endif
+
+    m_convReal = DoCreate();
+}
+
+wxCSConv::wxCSConv(wxFontEncoding encoding)
+{
+    if ( encoding == wxFONTENCODING_MAX || encoding == wxFONTENCODING_DEFAULT )
+    {
+        wxFAIL_MSG( wxT("invalid encoding value in wxCSConv ctor") );
+
+        encoding = wxFONTENCODING_SYSTEM;
+    }
+
+    Init();
+
+    SetEncoding(encoding);
+
+    m_convReal = DoCreate();
+}
+
+wxCSConv::~wxCSConv()
+{
+    Clear();
+}
+
+wxCSConv::wxCSConv(const wxCSConv& conv)
+        : wxMBConv()
+{
+    Init();
+
+    SetName(conv.m_name);
+    SetEncoding(conv.m_encoding);
+
+    m_convReal = DoCreate();
+}
+
+wxCSConv& wxCSConv::operator=(const wxCSConv& conv)
+{
+    Clear();
+
+    SetName(conv.m_name);
+    SetEncoding(conv.m_encoding);
+
+    m_convReal = DoCreate();
+
+    return *this;
+}
+
+void wxCSConv::Clear()
+{
+    free(m_name);
+    m_name = NULL;
+
+    wxDELETE(m_convReal);
+}
+
+void wxCSConv::SetName(const char *charset)
+{
+    if ( charset )
+        m_name = wxStrdup(charset);
+}
+
+#if wxUSE_FONTMAP
+
+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
+                       : (const char*)wxFontMapperBase::GetEncodingName(m_encoding).mb_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 )
+    {
+        // don't convert at all
+        return NULL;
+    }
+
+    // we trust OS to do conversion better than we can so try external
+    // conversion methods first
+    //
+    // the full order is:
+    //      1. OS conversion (iconv() under Unix or Win32 API)
+    //      2. hard coded conversions for UTF
+    //      3. wxEncodingConverter as fall back
+
+    // step (1)
+#ifdef HAVE_ICONV
+#if !wxUSE_FONTMAP
+    if ( m_name )
+#endif // !wxUSE_FONTMAP
+    {
+#if wxUSE_FONTMAP
+        wxFontEncoding encoding(m_encoding);
+#endif
+
+        if ( m_name )
+        {
+            wxMBConv_iconv *conv = new wxMBConv_iconv(m_name);
+            if ( conv->IsOk() )
+                return conv;
+
+            delete conv;
+
+#if wxUSE_FONTMAP
+            encoding =
+                wxFontMapperBase::Get()->CharsetToEncoding(m_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(it->second.ToAscii());
+                if ( conv->IsOk() )
+                    return conv;
+
+                delete conv;
+            }
+
+            const wxChar* const* names = wxFontMapperBase::GetAllEncodingNames(encoding);
+            // CS : in case this does not return valid names (eg for MacRoman)
+            // encoding got a 'failure' entry in the cache all the same,
+            // although it just has to be created using a different method, so
+            // only store failed iconv creation attempts (or perhaps we
+            // shoulnd't do this at all ?)
+            if ( names[0] != NULL )
+            {
+                for ( ; *names; ++names )
+                {
+                    // FIXME-UTF8: wxFontMapperBase::GetAllEncodingNames()
+                    //             will need changes that will obsolete this
+                    wxString name(*names);
+                    wxMBConv_iconv *conv = new wxMBConv_iconv(name.ToAscii());
+                    if ( conv->IsOk() )
+                    {
+                        gs_nameCache[encoding] = *names;
+                        return conv;
+                    }
+
+                    delete conv;
+                }
+
+                gs_nameCache[encoding] = wxT(""); // cache the failure
+            }
+        }
+#endif // wxUSE_FONTMAP
+    }
+#endif // HAVE_ICONV
+
+#ifdef wxHAVE_WIN32_MB2WC
+    {
+#if wxUSE_FONTMAP
+        wxMBConv_win32 *conv = m_name ? new wxMBConv_win32(m_name)
+                                      : new wxMBConv_win32(m_encoding);
+        if ( conv->IsOk() )
+            return conv;
+
+        delete conv;
+#else
+        return NULL;
+#endif
+    }
+#endif // wxHAVE_WIN32_MB2WC
+
+#ifdef __DARWIN__
+    {
+        // 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
+            wxMBConv_cf *conv = m_name ? new wxMBConv_cf(m_name)
+                                          : new wxMBConv_cf(m_encoding);
+#else
+            wxMBConv_cf *conv = new wxMBConv_cf(m_encoding);
+#endif
+
+            if ( conv->IsOk() )
+                 return conv;
+
+            delete conv;
+        }
+    }
+#endif // __DARWIN__
+
+    // step (2)
+    wxFontEncoding enc = m_encoding;
+#if wxUSE_FONTMAP
+    if ( enc == wxFONTENCODING_SYSTEM && m_name )
+    {
+        // 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 = wxFontMapperBase::Get()->CharsetToEncoding(m_name, false);
+    }
+#endif // wxUSE_FONTMAP
+
+    switch ( enc )
+    {
+        case wxFONTENCODING_UTF7:
+             return new wxMBConvUTF7;
+
+        case wxFONTENCODING_UTF8:
+             return new wxMBConvUTF8;
+
+        case wxFONTENCODING_UTF16BE:
+             return new wxMBConvUTF16BE;
+
+        case wxFONTENCODING_UTF16LE:
+             return new wxMBConvUTF16LE;
+
+        case wxFONTENCODING_UTF32BE:
+             return new wxMBConvUTF32BE;
+
+        case wxFONTENCODING_UTF32LE:
+             return new wxMBConvUTF32LE;
+
+        default:
+             // nothing to do but put here to suppress gcc warnings
+             break;
+    }
+
+    // step (3)
+#if wxUSE_FONTMAP
+    {
+        wxMBConv_wxwin *conv = m_name ? new wxMBConv_wxwin(m_name)
+                                      : new wxMBConv_wxwin(m_encoding);
+        if ( conv->IsOk() )
+            return conv;
+
+        delete conv;
+    }
+
+    wxLogTrace(TRACE_STRCONV,
+               wxT("encoding \"%s\" is not supported by this system"),
+               (m_name ? wxString(m_name)
+                       : wxFontMapperBase::GetEncodingName(m_encoding)));
+#endif // wxUSE_FONTMAP
+
+    return NULL;
+}
+
+bool wxCSConv::IsOk() const
+{
+    // special case: no convReal created for wxFONTENCODING_ISO8859_1
+    if ( m_encoding == wxFONTENCODING_ISO8859_1 )
+        return true; // always ok as we do it ourselves
+
+    // m_convReal->IsOk() is called at its own creation, so we know it must
+    // be ok if m_convReal is non-NULL
+    return m_convReal != NULL;
+}
+
+size_t wxCSConv::ToWChar(wchar_t *dst, size_t dstLen,
+                         const char *src, size_t srcLen) const
+{
+    if (m_convReal)
+        return m_convReal->ToWChar(dst, dstLen, src, srcLen);
+
+    // latin-1 (direct)
+    if ( srcLen == wxNO_LEN )
+        srcLen = strlen(src) + 1; // take trailing NUL too
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        for ( size_t n = 0; n < srcLen; n++ )
+            dst[n] = (unsigned char)(src[n]);
+    }
+
+    return srcLen;
+}
+
+size_t wxCSConv::FromWChar(char *dst, size_t dstLen,
+                           const wchar_t *src, size_t srcLen) const
+{
+    if (m_convReal)
+        return m_convReal->FromWChar(dst, dstLen, src, srcLen);
+
+    // latin-1 (direct)
+    if ( srcLen == wxNO_LEN )
+        srcLen = wxWcslen(src) + 1;
+
+    if ( dst )
+    {
+        if ( dstLen < srcLen )
+            return wxCONV_FAILED;
+
+        for ( size_t n = 0; n < srcLen; n++ )
+        {
+            if ( src[n] > 0xFF )
+                return wxCONV_FAILED;
+
+            dst[n] = (char)src[n];
+        }
+
+    }
+    else // still need to check the input validity
+    {
+        for ( size_t n = 0; n < srcLen; n++ )
+        {
+            if ( src[n] > 0xFF )
+                return wxCONV_FAILED;
+        }
+    }
+
+    return srcLen;
+}
+
+size_t wxCSConv::GetMBNulLen() const
+{
+    if ( m_convReal )
+        return m_convReal->GetMBNulLen();
+
+    // otherwise, we are ISO-8859-1
+    return 1;
+}
+
+#if wxUSE_UNICODE_UTF8
+bool wxCSConv::IsUTF8() const
+{
+    if ( m_convReal )
+        return m_convReal->IsUTF8();
+
+    // otherwise, we are ISO-8859-1
+    return false;
+}
+#endif
+
+
+#if wxUSE_UNICODE
+
+wxWCharBuffer wxSafeConvertMB2WX(const char *s)
+{
+    if ( !s )
+        return wxWCharBuffer();
+
+    wxWCharBuffer wbuf(wxConvLibc.cMB2WX(s));
+    if ( !wbuf )
+        wbuf = wxMBConvUTF8().cMB2WX(s);
+    if ( !wbuf )
+        wbuf = wxConvISO8859_1.cMB2WX(s);
+
+    return wbuf;
+}
+
+wxCharBuffer wxSafeConvertWX2MB(const wchar_t *ws)
+{
+    if ( !ws )
+        return wxCharBuffer();
+
+    wxCharBuffer buf(wxConvLibc.cWX2MB(ws));
+    if ( !buf )
+        buf = wxMBConvUTF8(wxMBConvUTF8::MAP_INVALID_UTF8_TO_OCTAL).cWX2MB(ws);
+
+    return buf;
+}
+
+#endif // wxUSE_UNICODE
 
 // ----------------------------------------------------------------------------
-// stand-ins in absence of wchar_t
+// globals
 // ----------------------------------------------------------------------------
 
-WXDLLEXPORT_DATA(wxMBConv) wxConvLibc, wxConvFile;
-
-#endif // wxUSE_WCHAR_T
+// NB: The reason why we create converted objects in this convoluted way,
+//     using a factory function instead of global variable, is that they
+//     may be used at static initialization time (some of them are used by
+//     wxString ctors and there may be a global wxString object). In other
+//     words, possibly _before_ the converter global object would be
+//     initialized.
+
+#undef wxConvLibc
+#undef wxConvUTF8
+#undef wxConvUTF7
+#undef wxConvLocal
+#undef wxConvISO8859_1
+
+#define WX_DEFINE_GLOBAL_CONV2(klass, impl_klass, name, ctor_args)      \
+    WXDLLIMPEXP_DATA_BASE(klass*) name##Ptr = NULL;                     \
+    WXDLLIMPEXP_BASE klass* wxGet_##name##Ptr()                         \
+    {                                                                   \
+        static impl_klass name##Obj ctor_args;                          \
+        return &name##Obj;                                              \
+    }                                                                   \
+    /* this ensures that all global converter objects are created */    \
+    /* by the time static initialization is done, i.e. before any */    \
+    /* thread is launched: */                                           \
+    static klass* gs_##name##instance = wxGet_##name##Ptr()
+
+#define WX_DEFINE_GLOBAL_CONV(klass, name, ctor_args) \
+    WX_DEFINE_GLOBAL_CONV2(klass, klass, name, ctor_args)
+
+#ifdef __INTELC__
+    // disable warning "variable 'xxx' was declared but never referenced"
+    #pragma warning(disable: 177)
+#endif // Intel C++
+
+#ifdef __WINDOWS__
+    WX_DEFINE_GLOBAL_CONV2(wxMBConv, wxMBConv_win32, wxConvLibc, wxEMPTY_PARAMETER_VALUE);
+#elif 0 // defined(__WXOSX__)
+    WX_DEFINE_GLOBAL_CONV2(wxMBConv, wxMBConv_cf, wxConvLibc,  (wxFONTENCODING_UTF8));
+#else
+    WX_DEFINE_GLOBAL_CONV2(wxMBConv, wxMBConvLibc, wxConvLibc, wxEMPTY_PARAMETER_VALUE);
+#endif
 
+// NB: we can't use wxEMPTY_PARAMETER_VALUE as final argument here because it's
+//     passed to WX_DEFINE_GLOBAL_CONV2 after a macro expansion and so still
+//     provokes an error message about "not enough macro parameters"; and we
+//     can't use "()" here as the name##Obj declaration would be parsed as a
+//     function declaration then, so use a semicolon and live with an extra
+//     empty statement (and hope that no compilers warns about this)
+WX_DEFINE_GLOBAL_CONV(wxMBConvStrictUTF8, wxConvUTF8, ;);
+WX_DEFINE_GLOBAL_CONV(wxMBConvUTF7, wxConvUTF7, ;);
+
+WX_DEFINE_GLOBAL_CONV(wxCSConv, wxConvLocal, (wxFONTENCODING_SYSTEM));
+WX_DEFINE_GLOBAL_CONV(wxCSConv, wxConvISO8859_1, (wxFONTENCODING_ISO8859_1));
+
+WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvCurrent = wxGet_wxConvLibcPtr();
+WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvUI = wxGet_wxConvLocalPtr();
+
+#ifdef __DARWIN__
+// It is important to use this conversion object under Darwin as it ensures
+// that Unicode strings are (re)composed correctly even though xnu kernel uses
+// decomposed form internally (at least for the file names).
+static wxMBConv_cf wxConvMacUTF8DObj(wxFONTENCODING_UTF8);
+#endif
 
+WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvFileName =
+#ifdef __DARWIN__
+                                    &wxConvMacUTF8DObj;
+#else // !__DARWIN__
+                                    wxGet_wxConvLibcPtr();
+#endif // __DARWIN__/!__DARWIN__