Change GetC to return an int so that it can return wxEOF on error.

[wxWidgets.git] / include / wx / strconv.h

diff --git a/include/wx/strconv.h b/include/wx/strconv.h
index 53b74ca6ccd2c5faad32db8b14d49386d3d03a38..c56ae9af2f206189494de646f46fc8e2864116e5 100644 (file)
--- a/include/wx/strconv.h
+++ b/include/wx/strconv.h
@@ -1,16 +1,17 @@
 ///////////////////////////////////////////////////////////////////////////////
 // Name:        strconv.h
 // Purpose:     conversion routines for char sets any Unicode
 ///////////////////////////////////////////////////////////////////////////////
 // Name:        strconv.h
 // Purpose:     conversion routines for char sets any Unicode

-// Author:      Robert Roebling, Ove Kaaven
+// Author:      Ove Kaaven, Robert Roebling, Vadim Zeitlin

 // Modified by:
 // Created:     29/01/98
 // RCS-ID:      $Id$
 // Modified by:
 // Created:     29/01/98
 // RCS-ID:      $Id$

-// Copyright:   (c) 1998 Ove Kaaven, Robert Roebling, Vadim Zeitlin
+// Copyright:   (c) 1998 Ove Kaaven, Robert Roebling
+//              (c) 1998-2006 Vadim Zeitlin

 // Licence:     wxWindows licence
 ///////////////////////////////////////////////////////////////////////////////
 
 // Licence:     wxWindows licence
 ///////////////////////////////////////////////////////////////////////////////
 

-#ifndef _WX_WXSTRCONVH__
-#define _WX_WXSTRCONVH__
+#ifndef _WX_STRCONV_H_
+#define _WX_STRCONV_H_

 
 #include "wx/defs.h"
 #include "wx/wxchar.h"
 
 #include "wx/defs.h"
 #include "wx/wxchar.h"


@@ -28,31 +29,67 @@
 
 #if wxUSE_WCHAR_T
 
 
 #if wxUSE_WCHAR_T
 

+// the error value returned by wxMBConv methods
+#define wxCONV_FAILED ((size_t)-1)
+
+// the default value for some length parameters meaning that the string is
+// NUL-terminated
+#define wxNO_LEN ((size_t)-1)
+

 // ----------------------------------------------------------------------------
 // wxMBConv (abstract base class for conversions)
 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 // wxMBConv (abstract base class for conversions)
 // ----------------------------------------------------------------------------
 

+// When deriving a new class from wxMBConv you must reimplement ToWChar() and
+// FromWChar() methods which are not pure virtual only for historical reasons,
+// don't let the fact that the existing classes implement MB2WC/WC2MB() instead
+// confuse you.
+//
+// You also have to implement Clone() to allow copying the conversions
+// polymorphically.
+//
+// And you might need to override GetMBNulLen() as well.

 class WXDLLIMPEXP_BASE wxMBConv
 {
 public:
 class WXDLLIMPEXP_BASE wxMBConv
 {
 public:

-    // The functions doing actual conversion. On success, the return value is
-    // the length (i.e. the number of characters, not bytes, and not counting
-    // the trailing L'\0') of the converted string. On failure, (size_t)-1 is
-    // returned. In the special case when outputBuf is NULL the return value is
-    // the same one but nothing is written to the buffer.
+    // The functions doing actual conversion from/to narrow to/from wide
+    // character strings.

     //
     //

-    // Note that outLen is the length of the output buffer, not the length of
-    // the input (which is always supposed to be terminated by one or more
-    // NULs, as appropriate for the encoding)!
-    virtual size_t MB2WC(wchar_t *out, const char *in, size_t outLen) const = 0;
-    virtual size_t WC2MB(char *out, const wchar_t *in, size_t outLen) const = 0;
+    // On success, the return value is the length (i.e. the number of
+    // characters, not bytes) of the converted string including any trailing
+    // L'\0' or (possibly multiple) '\0'(s). If the conversion fails or if
+    // there is not enough space for everything, including the trailing NUL
+    // character(s), in the output buffer, wxCONV_FAILED is returned.
+    //
+    // In the special case when dstLen is 0 (outputBuf may be NULL then) the
+    // return value is the length of the needed buffer but nothing happens
+    // otherwise. If srcLen is wxNO_LEN, the entire string, up to and
+    // including the trailing NUL(s), is converted, otherwise exactly srcLen
+    // bytes are.
+    //
+    // Typical usage:
+    //
+    //          size_t dstLen = conv.ToWChar(NULL, 0, src);
+    //          if ( dstLen != wxCONV_FAILED )
+    //              ... handle error ...
+    //          wchar_t *wbuf = new wchar_t[dstLen];
+    //          conv.ToWChar(wbuf, dstLen, src);
+    //
+    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;

 
 

-    // MB <-> WC
+
+    // Convenience functions for translating NUL-terminated strings: returns
+    // the buffer containing the converted string or NULL pointer if the
+    // conversion failed.

     const wxWCharBuffer cMB2WC(const char *in) const;
     const wxCharBuffer cWC2MB(const wchar_t *in) const;
 
     const wxWCharBuffer cMB2WC(const char *in) const;
     const wxCharBuffer cWC2MB(const wchar_t *in) const;
 

-    // Functions converting strings which may contain embedded NULs and don't
-    // have to be NUL-terminated.
+    // Convenience functions for converting strings which may contain embedded
+    // NULs and don't have to be NUL-terminated.

     //
     // inLen is the length of the buffer including trailing NUL if any: if the
     // last 4 bytes of the buffer are all NULs, these functions are more
     //
     // inLen is the length of the buffer including trailing NUL if any: if the
     // last 4 bytes of the buffer are all NULs, these functions are more


@@ -81,19 +118,49 @@ public:
     const wxWCharBuffer cWX2WC(const char *psz) const { return cMB2WC(psz); }
 #endif // Unicode/ANSI
 
     const wxWCharBuffer cWX2WC(const char *psz) const { return cMB2WC(psz); }
 #endif // Unicode/ANSI
 

-    // virtual dtor for any base class
-    virtual ~wxMBConv();
+    // this function is used in the implementation of cMB2WC() to distinguish
+    // between the following cases:
+    //
+    //      a) var width encoding with strings terminated by a single NUL
+    //         (usual multibyte encodings): return 1 in this case
+    //      b) fixed width encoding with 2 bytes/char and so terminated by
+    //         2 NULs (UTF-16/UCS-2 and variants): return 2 in this case
+    //      c) fixed width encoding with 4 bytes/char and so terminated by
+    //         4 NULs (UTF-32/UCS-4 and variants): return 4 in this case
+    //
+    // anything else is not supported currently and -1 should be returned
+    virtual size_t GetMBNulLen() const { return 1; }

 
 

-private:
-    // this function must return the multibyte representation of L'\0'
+    // return the maximal value currently returned by GetMBNulLen() for any
+    // encoding
+    static size_t GetMaxMBNulLen() { return 4 /* for UTF-32 */; }
+
+
+    // The old conversion functions. The existing classes currently mostly
+    // implement these ones but we're in transition to using To/FromWChar()
+    // instead and any new classes should implement just the new functions.
+    // For now, however, we provide default implementation of To/FromWChar() in
+    // this base class in terms of MB2WC/WC2MB() to avoid having to rewrite all
+    // the conversions at once.

     //
     //

-    // on error, nulLen should be set to -1
-    virtual const char *GetMBNul(size_t *nulLen) const
-    {
-        *nulLen = 1;
+    // On success, the return value is the length (i.e. the number of
+    // characters, not bytes) not counting the trailing NUL(s) of the converted
+    // string. On failure, (size_t)-1 is returned. In the special case when
+    // outputBuf is NULL the return value is the same one but nothing is
+    // written to the buffer.
+    //
+    // Note that outLen is the length of the output buffer, not the length of
+    // the input (which is always supposed to be terminated by one or more
+    // NULs, as appropriate for the encoding)!
+    virtual size_t MB2WC(wchar_t *out, const char *in, size_t outLen) const;
+    virtual size_t WC2MB(char *out, const wchar_t *in, size_t outLen) const;

 
 

-        return "";
-    }
+
+    // make a heap-allocated copy of this object
+    virtual wxMBConv *Clone() const = 0;
+
+    // virtual dtor for any base class
+    virtual ~wxMBConv();

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -106,6 +173,8 @@ class WXDLLIMPEXP_BASE wxMBConvLibc : public wxMBConv
 public:
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
 public:
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;

+
+    virtual wxMBConv *Clone() const { return new wxMBConvLibc; }

 };
 
 #ifdef __UNIX__
 };
 
 #ifdef __UNIX__


@@ -121,6 +190,11 @@ class WXDLLIMPEXP_BASE wxConvBrokenFileNames : public wxMBConv
 {
 public:
     wxConvBrokenFileNames(const wxChar *charset);
 {
 public:
     wxConvBrokenFileNames(const wxChar *charset);

+    wxConvBrokenFileNames(const wxConvBrokenFileNames& conv)
+        : wxMBConv(),
+          m_conv(conv.m_conv ? conv.m_conv->Clone() : NULL)
+    {
+    }

     virtual ~wxConvBrokenFileNames() { delete m_conv; }
 
     virtual size_t MB2WC(wchar_t *out, const char *in, size_t outLen) const
     virtual ~wxConvBrokenFileNames() { delete m_conv; }
 
     virtual size_t MB2WC(wchar_t *out, const char *in, size_t outLen) const


@@ -133,16 +207,19 @@ public:
         return m_conv->WC2MB(out, in, outLen);
     }
 
         return m_conv->WC2MB(out, in, outLen);
     }
 

-private:
-    virtual const char *GetMBNul(size_t *nulLen) const
+    virtual size_t GetMBNulLen() const

     {
         // cast needed to call a private function
     {
         // cast needed to call a private function

-        return ((wxConvBrokenFileNames *)m_conv)->GetMBNul(nulLen);
+        return m_conv->GetMBNulLen();

     }
 
     }
 

+    virtual wxMBConv *Clone() const { return new wxConvBrokenFileNames(*this); }

 
 

+private:

     // the conversion object we forward to
     wxMBConv *m_conv;
     // the conversion object we forward to
     wxMBConv *m_conv;

+
+    DECLARE_NO_ASSIGN_CLASS(wxConvBrokenFileNames)

 };
 
 #endif // __UNIX__
 };
 
 #endif // __UNIX__


@@ -156,6 +233,8 @@ class WXDLLIMPEXP_BASE wxMBConvUTF7 : public wxMBConv
 public:
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
 public:
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;

+
+    virtual wxMBConv *Clone() const { return new wxMBConvUTF7; }

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -165,7 +244,8 @@ public:
 class WXDLLIMPEXP_BASE wxMBConvUTF8 : public wxMBConv
 {
 public:
 class WXDLLIMPEXP_BASE wxMBConvUTF8 : public wxMBConv
 {
 public:

-    enum {
+    enum
+    {

         MAP_INVALID_UTF8_NOT = 0,
         MAP_INVALID_UTF8_TO_PUA = 1,
         MAP_INVALID_UTF8_TO_OCTAL = 2
         MAP_INVALID_UTF8_NOT = 0,
         MAP_INVALID_UTF8_TO_PUA = 1,
         MAP_INVALID_UTF8_TO_OCTAL = 2


@@ -175,6 +255,8 @@ public:
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
 
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
 

+    virtual wxMBConv *Clone() const { return new wxMBConvUTF8(m_options); }
+

 private:
     int m_options;
 };
 private:
     int m_options;
 };


@@ -185,12 +267,17 @@ private:
 
 class WXDLLIMPEXP_BASE wxMBConvUTF16Base : public wxMBConv
 {
 
 class WXDLLIMPEXP_BASE wxMBConvUTF16Base : public wxMBConv
 {

-private:
-    virtual const char *GetMBNul(size_t *nulLen) const
-    {
-        *nulLen = 2;
-        return "\0";
-    }
+public:
+    enum { BYTES_PER_CHAR = 2 };
+
+    virtual size_t GetMBNulLen() const { return BYTES_PER_CHAR; }
+
+protected:
+    // return the length of the buffer using srcLen if it's not wxNO_LEN and
+    // computing the length ourselves if it is; also checks that the length is
+    // even if specified as we need an entire number of UTF-16 characters and
+    // returns wxNO_LEN which indicates error if it is odd
+    static size_t GetLength(const char *src, size_t srcLen);

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -200,8 +287,11 @@ private:
 class WXDLLIMPEXP_BASE wxMBConvUTF16LE : public wxMBConvUTF16Base
 {
 public:
 class WXDLLIMPEXP_BASE wxMBConvUTF16LE : public wxMBConvUTF16Base
 {
 public:

-    virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
-    virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
+    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 wxMBConv *Clone() const { return new wxMBConvUTF16LE; }

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -211,8 +301,11 @@ public:
 class WXDLLIMPEXP_BASE wxMBConvUTF16BE : public wxMBConvUTF16Base
 {
 public:
 class WXDLLIMPEXP_BASE wxMBConvUTF16BE : public wxMBConvUTF16Base
 {
 public:

-    virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
-    virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
+    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 wxMBConv *Clone() const { return new wxMBConvUTF16BE; }

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -221,12 +314,16 @@ public:
 
 class WXDLLIMPEXP_BASE wxMBConvUTF32Base : public wxMBConv
 {
 
 class WXDLLIMPEXP_BASE wxMBConvUTF32Base : public wxMBConv
 {

-private:
-    virtual const char *GetMBNul(size_t *nulLen) const
-    {
-        *nulLen = 4;
-        return "\0\0\0";
-    }
+public:
+    enum { BYTES_PER_CHAR = 4 };
+
+    virtual size_t GetMBNulLen() const { return BYTES_PER_CHAR; }
+
+protected:
+    // this is similar to wxMBConvUTF16Base method with the same name except
+    // that, of course, it verifies that length is divisible by 4 if given and
+    // not by 2
+    static size_t GetLength(const char *src, size_t srcLen);

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -236,8 +333,11 @@ private:
 class WXDLLIMPEXP_BASE wxMBConvUTF32LE : public wxMBConvUTF32Base
 {
 public:
 class WXDLLIMPEXP_BASE wxMBConvUTF32LE : public wxMBConvUTF32Base
 {
 public:

-    virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
-    virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
+    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 wxMBConv *Clone() const { return new wxMBConvUTF32LE; }

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -247,8 +347,11 @@ public:
 class WXDLLIMPEXP_BASE wxMBConvUTF32BE : public wxMBConvUTF32Base
 {
 public:
 class WXDLLIMPEXP_BASE wxMBConvUTF32BE : public wxMBConvUTF32Base
 {
 public:

-    virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
-    virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
+    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 wxMBConv *Clone() const { return new wxMBConvUTF32BE; }

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -272,8 +375,10 @@ public:
 
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;
 
     virtual size_t MB2WC(wchar_t *outputBuf, const char *psz, size_t outputSize) const;
     virtual size_t WC2MB(char *outputBuf, const wchar_t *psz, size_t outputSize) const;

+    virtual size_t GetMBNulLen() const;
+    virtual wxMBConv *Clone() const { return new wxCSConv(*this); }

 
 

-    void Clear() ;
+    void Clear();

 
 private:
     // common part of all ctors
 
 private:
     // common part of all ctors


@@ -289,8 +394,6 @@ private:
     // charset string
     void SetName(const wxChar *charset);
 
     // charset string
     void SetName(const wxChar *charset);
 

-    virtual const char *GetMBNul(size_t *nulLen) const;
-

 
     // note that we can't use wxString here because of compilation
     // dependencies: we're included from wx/string.h
 
     // note that we can't use wxString here because of compilation
     // dependencies: we're included from wx/string.h


@@ -332,9 +435,14 @@ extern WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvFileName;
 // default in a couple of places inside wx (initially same as wxConvLibc)
 extern WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvCurrent;
 
 // default in a couple of places inside wx (initially same as wxConvLibc)
 extern WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvCurrent;
 

-// ???
+// the conversion corresponding to the current locale

 extern WXDLLIMPEXP_DATA_BASE(wxCSConv&) wxConvLocal;
 
 extern WXDLLIMPEXP_DATA_BASE(wxCSConv&) wxConvLocal;
 

+// the conversion corresponding to the encoding of the standard UI elements
+//
+// by default this is the same as wxConvLocal but may be changed if the program
+// needs to use a fixed encoding
+extern WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvUI;

 
 // ----------------------------------------------------------------------------
 // endianness-dependent conversions
 
 // ----------------------------------------------------------------------------
 // endianness-dependent conversions


@@ -411,6 +519,5 @@ extern WXDLLIMPEXP_DATA_BASE(wxMBConv *) wxConvCurrent;
     #define wxConvertMB2WX(s)   (s)
 #endif // Unicode/ANSI
 
     #define wxConvertMB2WX(s)   (s)
 #endif // Unicode/ANSI
 

-#endif
-  // _WX_WXSTRCONVH__
+#endif // _WX_STRCONV_H_