///////////////////////////////////////////////////////////////////////////// // Name: strconv.h // Purpose: interface of wxMBConvUTF7 // Author: wxWidgets team // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// /** @class wxMBConv This class is the base class of a hierarchy of classes capable of converting text strings between multibyte (SBCS or DBCS) encodings and Unicode. This is an abstract base class which defines the operations implemented by all different conversion classes. The derived classes don't add any new operations of their own (except, possibly, some non-default constructors) and so you should simply use this class ToWChar() and FromWChar() (or cMB2WC() and cWC2MB()) methods with the objects of the derived class. In the documentation for this and related classes please notice that length of the string refers to the number of characters in the string not counting the terminating @c NUL, if any. While the size of the string is the total number of bytes in the string, including any trailing @c NUL. Thus, length of wide character string @c L"foo" is 3 while its size can be either 8 or 16 depending on whether @c wchar_t is 2 bytes (as under Windows) or 4 (Unix). @library{wxbase} @category{conv} @see wxCSConv, wxEncodingConverter, @ref overview_mbconv */ class wxMBConv { public: /** Trivial default constructor. */ wxMBConv(); /** This pure virtual function is overridden in each of the derived classes to return a new copy of the object it is called on. It is used for copying the conversion objects while preserving their dynamic type. */ virtual wxMBConv* Clone() const = 0; /** This function returns 1 for most of the multibyte encodings in which the string is terminated by a single @c NUL, 2 for UTF-16 and 4 for UTF-32 for which the string is terminated with 2 and 4 @c NUL characters respectively. The other cases are not currently supported and @c wxCONV_FAILED (defined as -1) is returned for them. */ virtual size_t GetMBNulLen() const; /** Returns the maximal value which can be returned by GetMBNulLen() for any conversion object. Currently this value is 4. This method can be used to allocate the buffer with enough space for the trailing @c NUL characters for any encoding. */ static size_t GetMaxMBNulLen(); /** Convert multibyte string to a wide character one. This is the most general function for converting a multibyte string to a wide string, cMB2WC() may be often more convenient, however this function is the most efficient one as it allows to avoid any unnecessary copying. The main case is when @a dst is not @NULL and @a srcLen is not @c wxNO_LEN (which is defined as @c (size_t)-1): then the function converts exactly @a srcLen bytes starting at @a src into wide string which it output to @e dst. If the length of the resulting wide string is greater than @e dstLen, an error is returned. Note that if @a srcLen bytes don't include @c NUL characters, the resulting wide string is not @c NUL-terminated neither. If @a srcLen is @c wxNO_LEN, the function supposes that the string is properly (i.e. as necessary for the encoding handled by this conversion) @c NUL-terminated and converts the entire string, including any trailing @c NUL bytes. In this case the wide string is also @c NUL-terminated. Finally, if @a dst is @NULL, the function returns the length of the needed buffer. Example of use of this function: @code size_t dstLen = conv.ToWChar(NULL, 0, src); if ( dstLen == wxCONV_FAILED ) ... handle error ... wchar_t *dst = new wchar_t[dstLen]; if ( conv.ToWChar(dst, dstLen, src) == wxCONV_FAILED ) ... handle error ... @endcode Notice that when passing the explicit source length the output will @e not be @c NUL terminated if you pass @c strlen(str) as parameter. Either leave @a srcLen as default @c wxNO_LEN or add one to @c strlen result if you want the output to be @c NUL terminated. @param dst Pointer to output buffer of the size of at least @a dstLen or @NULL. @param dstLen Maximal number of characters to be written to the output buffer if @a dst is non-@NULL, unused otherwise. @param src Point to the source string, must not be @NULL. @param srcLen The number of characters of the source string to convert or @c wxNO_LEN (default parameter) to convert everything up to and including the terminating @c NUL character(s). @return The number of character written (or which would have been written if it were non-@NULL) to @a dst or @c wxCONV_FAILED on error. */ virtual size_t ToWChar(wchar_t* dst, size_t dstLen, const char* src, size_t srcLen = wxNO_LEN) const; /** Converts wide character string to multibyte. This function has the same semantics as ToWChar() except that it converts a wide string to multibyte one. As with ToWChar(), it may be more convenient to use cWC2MB() when working with @c NUL terminated strings. @param dst Pointer to output buffer of the size of at least @a dstLen or @NULL. @param dstLen Maximal number of characters to be written to the output buffer if @a dst is non-@NULL, unused otherwise. @param src Point to the source string, must not be @NULL. @param srcLen The number of characters of the source string to convert or @c wxNO_LEN (default parameter) to convert everything up to and including the terminating @c NUL character. @return The number of character written (or which would have been written if it were non-@NULL) to @a dst or @c wxCONV_FAILED on error. */ virtual size_t FromWChar(char* dst, size_t dstLen, const wchar_t* src, size_t srcLen = wxNO_LEN) const; /** Converts from multibyte encoding to Unicode by calling ToWChar() and allocating a temporary wxWCharBuffer to hold the result. This function is a convenient wrapper around ToWChar() as it takes care of allocating the buffer of the necessary size itself. Its parameters have the same meaning as for ToWChar(), in particular @a inLen can be specified explicitly in which case exactly that many characters are converted and @a outLen receives (if non-@NULL) exactly the corresponding number of wide characters, whether the last one of them is @c NUL or not. However if @c inLen is @c wxNO_LEN, then @c outLen doesn't count the trailing @c NUL even if it is always present in this case. Finally notice that if the conversion fails, the returned buffer is invalid and @a outLen is set to 0 (and not @c wxCONV_FAILED for compatibility concerns). */ const wxWCharBuffer cMB2WC(const char* in, size_t inLen, size_t *outLen) const; /** Converts a char buffer to wide char one. This is the most convenient and safest conversion function as you don't have to deal with the buffer lengths directly. Use it if the input buffer is known not to be empty or if you are sure that the conversion is going to succeed -- otherwise, use the overload above to be able to distinguish between empty input and conversion failure. @return The buffer containing the converted text, empty if the input was empty or if the conversion failed. @since 2.9.1 */ const wxWCharBuffer cMB2WC(const wxCharBuffer& buf) const; //@{ /** Converts from multibyte encoding to the current wxChar type (which depends on whether wxUSE_UNICODE is set to 1). If wxChar is char, it returns the parameter unaltered. If wxChar is wchar_t, it returns the result in a wxWCharBuffer. The macro wxMB2WXbuf is defined as the correct return type (without const). */ const char* cMB2WX(const char* psz) const; const wxWCharBuffer cMB2WX(const char* psz) const; //@} /** Converts from Unicode to multibyte encoding by calling FromWChar() and allocating a temporary wxCharBuffer to hold the result. This function is a convenient wrapper around FromWChar() as it takes care of allocating the buffer of necessary size itself. Its parameters have the same meaning as the corresponding parameters of FromWChar(), please see the description of cMB2WC() for more details. */ const wxCharBuffer cWC2MB(const wchar_t* in, size_t inLen, size_t *outLen) const; /** Converts a wide char buffer to char one. This is the most convenient and safest conversion function as you don't have to deal with the buffer lengths directly. Use it if the input buffer is known not to be empty or if you are sure that the conversion is going to succeed -- otherwise, use the overload above to be able to distinguish between empty input and conversion failure. @return The buffer containing the converted text, empty if the input was empty or if the conversion failed. @since 2.9.1 */ const wxCharBuffer cWC2MB(const wxWCharBuffer& buf) const; //@{ /** Converts from Unicode to the current wxChar type. If wxChar is wchar_t, it returns the parameter unaltered. If wxChar is char, it returns the result in a wxCharBuffer. The macro wxWC2WXbuf is defined as the correct return type (without const). */ const wchar_t* cWC2WX(const wchar_t* psz) const; const wxCharBuffer cWC2WX(const wchar_t* psz) const; //@} //@{ /** Converts from the current wxChar type to multibyte encoding. If wxChar is char, it returns the parameter unaltered. If wxChar is wchar_t, it returns the result in a wxCharBuffer. The macro wxWX2MBbuf is defined as the correct return type (without const). */ const char* cWX2MB(const wxChar* psz) const; const wxCharBuffer cWX2MB(const wxChar* psz) const; //@} //@{ /** Converts from the current wxChar type to Unicode. If wxChar is wchar_t, it returns the parameter unaltered. If wxChar is char, it returns the result in a wxWCharBuffer. The macro wxWX2WCbuf is defined as the correct return type (without const). */ const wchar_t* cWX2WC(const wxChar* psz) const; const wxWCharBuffer cWX2WC(const wxChar* psz) const; //@} /** @deprecated This function is deprecated, please use ToWChar() instead. Converts from a string @a in multibyte encoding to Unicode putting up to @a outLen characters into the buffer @e out. If @a out is @NULL, only the length of the string which would result from the conversion is calculated and returned. Note that this is the length and not size, i.e. the returned value does not include the trailing @c NUL. But when the function is called with a non-@NULL @a out buffer, the @a outLen parameter should be one more to allow to properly @c NUL-terminate the string. So to properly use this function you need to write: @code size_t lenConv = conv.MB2WC(NULL, in, 0); if ( lenConv == wxCONV_FAILED ) ... handle error ... // allocate 1 more character for the trailing NUL and also pass // the size of the buffer to the function now wchar_t *out = new wchar_t[lenConv + 1]; if ( conv.MB2WC(out, in, lenConv + 1) == wxCONV_FAILED ) ... handle error ... @endcode For this and other reasons, ToWChar() is strongly recommended as a replacement. @param out The output buffer, may be @NULL if the caller is only interested in the length of the resulting string @param in The NUL-terminated input string, cannot be @NULL @param outLen The length of the output buffer but including NUL, ignored if out is @NULL @return The length of the converted string excluding the trailing NUL. */ virtual size_t MB2WC(wchar_t* out, const char* in, size_t outLen) const; /** @deprecated This function is deprecated, please use FromWChar() instead. Converts from Unicode to multibyte encoding. The semantics of this function (including the return value meaning) is the same as for wxMBConv::MB2WC. Notice that when the function is called with a non-@NULL buffer, the @a n parameter should be the size of the buffer and so it should take into account the trailing @c NUL, which might take two or four bytes for some encodings (UTF-16 and UTF-32) and not one, i.e. GetMBNulLen(). */ virtual size_t WC2MB(char* buf, const wchar_t* psz, size_t n) const; }; /** @class wxMBConvUTF7 This class converts between the UTF-7 encoding and Unicode. It has one predefined instance, @b wxConvUTF7. Notice that, unlike all the other conversion objects, this converter is stateful, i.e. it remembers its state from the last call to its ToWChar() or FromWChar() and assumes it is called on the continuation of the same string when the same method is called again. This assumption is only made if an explicit length is specified as parameter to these functions as if an entire @c NUL terminated string is processed the state doesn't need to be remembered. This also means that, unlike the other predefined conversion objects, @b wxConvUTF7 is @em not thread-safe. @library{wxbase} @category{conv} @see wxMBConvUTF8, @ref overview_mbconv */ class wxMBConvUTF7 : public wxMBConv { }; /** @class wxMBConvUTF8 This class converts between the UTF-8 encoding and Unicode. It has one predefined instance, @b wxConvUTF8. @library{wxbase} @category{conv} @see wxMBConvUTF7, @ref overview_mbconv */ class wxMBConvUTF8 : public wxMBConv { }; /** @class wxMBConvUTF16 This class is used to convert between multibyte encodings and UTF-16 Unicode encoding (also known as UCS-2). Unlike UTF-8 encoding, UTF-16 uses words and not bytes and hence depends on the byte ordering: big or little endian. Hence this class is provided in two versions: wxMBConvUTF16LE and wxMBConvUTF16BE and wxMBConvUTF16 itself is just a typedef for one of them (native for the given platform, e.g. LE under Windows and BE under Mac). @library{wxbase} @category{conv} @see wxMBConvUTF8, wxMBConvUTF32, @ref overview_mbconv */ class wxMBConvUTF16 : public wxMBConv { }; /** @class wxMBConvUTF32 This class is used to convert between multibyte encodings and UTF-32 Unicode encoding (also known as UCS-4). Unlike UTF-8 encoding, UTF-32 uses (double) words and not bytes and hence depends on the byte ordering: big or little endian. Hence this class is provided in two versions: wxMBConvUTF32LE and wxMBConvUTF32BE and wxMBConvUTF32 itself is just a typedef for one of them (native for the given platform, e.g. LE under Windows and BE under Mac). @library{wxbase} @category{conv} @see wxMBConvUTF8, wxMBConvUTF16, @ref overview_mbconv */ class wxMBConvUTF32 : public wxMBConv { }; /** @class wxCSConv This class converts between any character set supported by the system and Unicode. Please notice that this class uses system-provided conversion functions, e.g. @c MultiByteToWideChar() and @c WideCharToMultiByte() under MSW and @c iconv(3) under Unix systems and as such may support different encodings and different encoding names on different platforms (although all relatively common encodings are supported should be supported everywhere). It has one predefined instance, @b wxConvLocal, for the default user character set. @library{wxbase} @category{conv} @see wxMBConv, wxEncodingConverter, @ref overview_mbconv */ class wxCSConv : public wxMBConv { public: /** Constructor. You can specify the name of the character set you want to convert from/to. If the character set name is not recognized, ISO 8859-1 is used as fall back, use IsOk() to test for this. @param charset The name of the encoding, shouldn't be empty. */ wxCSConv(const wxString& charset); /** Constructor. You can specify an encoding constant for the character set you want to convert from/to. Use IsOk() after construction to check whether the encoding is supported by the current system. @param encoding Any valid (i.e. not wxFONTENCODING_MAX) font encoding. */ wxCSConv(wxFontEncoding encoding); /** Returns @true if the charset (or the encoding) given at constructor is really available to use. Returns @false if ISO 8859-1 will be used instead. Note this does not mean that a given string will be correctly converted. A malformed string may still make conversion functions return @c wxCONV_FAILED. @since 2.8.2 */ bool IsOk() const; }; /** Conversion object used for converting file names from their external representation to the one used inside the program. @b wxConvFileName converts filenames between filesystem multibyte encoding and Unicode. @b wxConvFileName can also be set to a something else at run-time which is used e.g. by wxGTK to use an object which checks the environment variable @b G_FILESYSTEM_ENCODING indicating that filenames should not be interpreted as UTF8 and also for converting invalid UTF8 characters (e.g. if there is a filename in iso8859_1) to strings with octal values. Since some platforms (such as Win32) use Unicode in the filenames, and others (such as Unix) use multibyte encodings, this object should only be used directly if wxMBFILES is defined to 1. A convenience macro, @c wxFNCONV, is defined to @c wxConvFileName->cWX2MB in this case. You could use it like this: @code wxChar *name = "rawfile.doc"; FILE *fil = fopen(wxFNCONV(name), "r"); @endcode (although it would be better to just use wxFopen(name, "r") in this particular case, you only need to use this object for functions taking file names not wrapped by wxWidgets.) @library{wxbase} @category{conv} @see @ref overview_mbconv */ extern wxMBConv* wxConvFileName;