]> git.saurik.com Git - wxWidgets.git/blobdiff - include/wx/buffer.h
added template wxScopedArray<> too
[wxWidgets.git] / include / wx / buffer.h
index 1c54c504040c52d1737ecbd641a64c03850d0892..4cc340aa518fa7248e26b58781b93958a3596c5a 100644 (file)
 #ifndef _WX_BUFFER_H
 #define _WX_BUFFER_H
 
-#include "wx/wxchar.h"
+#include "wx/chartype.h"
+#include "wx/wxcrtbase.h"
 
+#ifndef __WXPALMOS5__
 #include <stdlib.h>             // malloc() and free()
+#endif // ! __WXPALMOS5__
+
+class WXDLLIMPEXP_FWD_BASE wxCStrData;
 
 // ----------------------------------------------------------------------------
 // Special classes for (wide) character strings: they use malloc/free instead
 // of new/delete
 // ----------------------------------------------------------------------------
 
-#define DEFINE_BUFFER(classname, chartype, strdupfunc)                      \
-class WXDLLIMPEXP_BASE classname                                            \
-{                                                                           \
-public:                                                                     \
-    classname(const chartype *str = NULL)                                   \
-        : m_str(str ? strdupfunc(str) : NULL)                               \
-    {                                                                       \
-    }                                                                       \
-                                                                            \
-    classname(size_t len)                                                   \
-        : m_str((chartype *)malloc((len + 1)*sizeof(chartype)))             \
-    {                                                                       \
-        m_str[len] = (chartype)0;                                           \
-    }                                                                       \
-                                                                            \
-    /* no need to check for NULL, free() does it */                         \
-    ~classname() { free(m_str); }                                           \
-                                                                            \
-    /*                                                                      \
-        WARNING:                                                            \
-                                                                            \
-        the copy ctor and assignment operators change the passed in object  \
-        even although it is declared as "const", so:                        \
-                                                                            \
-        a) it shouldn't be really const                                     \
-        b) you shouldn't use it afterwards (or know that it was reset)      \
-                                                                            \
-        This is very ugly but is unfortunately needed to make the normal use\
-        of classname buffer objects possible and is very similar to what    \
-        std::auto_ptr<> does (as if it were an excuse...)                   \
-    */                                                                      \
-                                                                            \
-    /*                                                                      \
-       because of the remark above, release() is declared const even if it  \
-       isn't really const                                                   \
-     */                                                                     \
-    chartype *release() const                                               \
-    {                                                                       \
-        chartype *p = m_str;                                                \
-        ((classname *)this)->m_str = NULL;                                  \
-        return p;                                                           \
-    }                                                                       \
-                                                                            \
-    classname(const classname& src)                                         \
-        : m_str(src.release())                                              \
-    {                                                                       \
-    }                                                                       \
-                                                                            \
-    classname& operator=(const chartype *str)                               \
-    {                                                                       \
-        free(m_str);                                                        \
-        m_str = str ? strdupfunc(str) : NULL;                               \
-        return *this;                                                       \
-    }                                                                       \
-                                                                            \
-    classname& operator=(const classname& src)                              \
-    {                                                                       \
-        free(m_str);                                                        \
-        m_str = src.release();                                              \
-                                                                            \
-        return *this;                                                       \
-    }                                                                       \
-                                                                            \
-    bool extend(size_t len)                                                 \
-    {                                                                       \
-        chartype *                                                          \
-            str = (chartype *)realloc(m_str, (len + 1)*sizeof(chartype));   \
-        if ( !str )                                                         \
-            return false;                                                   \
-                                                                            \
-        m_str = str;                                                        \
-                                                                            \
-        return true;                                                        \
-    }                                                                       \
-                                                                            \
-    chartype *data() { return m_str; }                                      \
-    const chartype *data() const { return m_str; }                          \
-    operator const chartype *() const { return m_str; }                     \
-    chartype operator[](size_t n) const { return m_str[n]; }                \
-                                                                            \
-private:                                                                    \
-    chartype *m_str;                                                        \
-}
-
-DEFINE_BUFFER(wxCharBuffer, char, wxStrdupA);
+// helpers used by wxCharTypeBuffer
+namespace wxPrivate
+{
+
+struct UntypedBufferData
+{
+    enum Kind
+    {
+        Owned,
+        NonOwned
+    };
+
+    UntypedBufferData(void *str, Kind kind = Owned)
+        : m_str(str), m_ref(1), m_owned(kind == Owned) {}
+
+    ~UntypedBufferData()
+    {
+        if ( m_owned )
+            free(m_str);
+    }
+
+    void *m_str;
+
+    // "short" to have sizeof(Data)=8 on 32bit archs
+    unsigned short m_ref;
+
+    bool m_owned;
+};
+
+// this has to be defined inside the DLL (and not e.g. as a static variable
+// inside an inline function) as otherwise MSVC gives link errors when the
+// functions are effectively inlined (i.e. in non-debug build)
+//
+// NB: this is defined in string.cpp and not the (non-existent) buffer.cpp
+extern WXDLLIMPEXP_DATA_BASE(UntypedBufferData * const) untypedNullDataPtr;
+
+} // namespace wxPrivate
+
+template <typename T>
+class wxCharTypeBuffer
+{
+public:
+    typedef T CharType;
+
+    wxCharTypeBuffer(const CharType *str = NULL)
+    {
+        if ( str )
+            m_data = new Data(wxStrdup(str));
+        else
+            m_data = GetNullData();
+    }
+
+    wxCharTypeBuffer(size_t len)
+    {
+        m_data = new Data((CharType *)malloc((len + 1)*sizeof(CharType)));
+        m_data->Get()[len] = (CharType)0;
+    }
+
+    static const wxCharTypeBuffer CreateNonOwned(const CharType *str)
+    {
+        wxCharTypeBuffer buf;
+        if ( str )
+            buf.m_data = new Data(const_cast<CharType*>(str), Data::NonOwned);
+        return buf;
+    }
+
+    ~wxCharTypeBuffer()
+    {
+        DecRef();
+    }
+
+    // NB: this method is only const for backward compatibility. It used to
+    //     be needed for auto_ptr-like semantics of the copy ctor, but now
+    //     that ref-counting is used, it's not really needed.
+    CharType *release() const
+    {
+        if ( m_data == GetNullData() )
+            return NULL;
+
+        wxASSERT_MSG( m_data->m_owned, _T("can't release non-owned buffer") );
+        wxASSERT_MSG( m_data->m_ref == 1, _T("can't release shared buffer") );
+
+        CharType * const p = m_data->Get();
+
+        wxCharTypeBuffer *self = const_cast<wxCharTypeBuffer*>(this);
+        self->m_data->Set(NULL);
+        self->DecRef();
+
+        return p;
+    }
+
+    void reset()
+    {
+        DecRef();
+    }
+
+    wxCharTypeBuffer(const wxCharTypeBuffer& src)
+    {
+        m_data = src.m_data;
+        IncRef();
+    }
+
+    wxCharTypeBuffer& operator=(const CharType *str)
+    {
+        DecRef();
+
+        if ( str )
+            m_data = new Data(wxStrdup(str));
+        return *this;
+    }
+
+    wxCharTypeBuffer& operator=(const wxCharTypeBuffer& src)
+    {
+        if ( &src == this )
+            return *this;
+
+        DecRef();
+        m_data = src.m_data;
+        IncRef();
+
+        return *this;
+    }
+
+    bool extend(size_t len)
+    {
+        wxASSERT_MSG( m_data->m_owned, _T("cannot extend non-owned buffer") );
+        wxASSERT_MSG( m_data->m_ref == 1, _T("can't extend shared buffer") );
+
+        CharType *str =
+            (CharType *)realloc(data(), (len + 1) * sizeof(CharType));
+        if ( !str )
+            return false;
+
+        if ( m_data == GetNullData() )
+        {
+            m_data = new Data(str);
+        }
+        else
+        {
+            m_data->Set(str);
+            m_data->m_owned = true;
+        }
+
+        return true;
+    }
+
+    CharType *data() { return m_data->Get(); }
+    const CharType *data() const { return  m_data->Get(); }
+    operator const CharType *() const { return data(); }
+    CharType operator[](size_t n) const { return data()[n]; }
+
+private:
+    // reference-counted data
+    struct Data : public wxPrivate::UntypedBufferData
+    {
+        Data(CharType *str, Kind kind = Owned)
+            : wxPrivate::UntypedBufferData(str, kind)
+        {
+        }
+
+        CharType *Get() const { return static_cast<CharType *>(m_str); }
+        void Set(CharType *str) { m_str = str; }
+    };
+
+    // placeholder for NULL string, to simplify this code
+    static Data *GetNullData()
+    {
+        return static_cast<Data *>(wxPrivate::untypedNullDataPtr);
+    }
+
+    void IncRef()
+    {
+        if ( m_data == GetNullData() ) // exception, not ref-counted
+            return;
+        m_data->m_ref++;
+    }
+
+    void DecRef()
+    {
+        if ( m_data == GetNullData() ) // exception, not ref-counted
+            return;
+        if ( --m_data->m_ref == 0 )
+            delete m_data;
+        m_data = GetNullData();
+    }
+
+private:
+    Data *m_data;
+};
+
+WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxCharTypeBuffer<char> )
+
+class wxCharBuffer : public wxCharTypeBuffer<char>
+{
+public:
+    typedef wxCharTypeBuffer<char> wxCharTypeBufferBase;
+
+    wxCharBuffer(const wxCharTypeBufferBase& buf)
+        : wxCharTypeBufferBase(buf) {}
+
+    wxCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {}
+    wxCharBuffer(size_t len) : wxCharTypeBufferBase(len) {}
+
+    wxCharBuffer(const wxCStrData& cstr);
+};
 
 #if wxUSE_WCHAR_T
+WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxCharTypeBuffer<wchar_t> )
 
-DEFINE_BUFFER(wxWCharBuffer, wchar_t, wxStrdupW);
+class wxWCharBuffer : public wxCharTypeBuffer<wchar_t>
+{
+public:
+    typedef wxCharTypeBuffer<wchar_t> wxCharTypeBufferBase;
 
+    wxWCharBuffer(const wxCharTypeBufferBase& buf)
+        : wxCharTypeBufferBase(buf) {}
+
+    wxWCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {}
+    wxWCharBuffer(size_t len) : wxCharTypeBufferBase(len) {}
+
+    wxWCharBuffer(const wxCStrData& cstr);
+};
 #endif // wxUSE_WCHAR_T
 
-#undef DEFINE_BUFFER
+// wxCharTypeBuffer<T> implicitly convertible to T*
+template <typename T>
+class wxWritableCharTypeBuffer : public wxCharTypeBuffer<T>
+{
+public:
+    typedef typename wxCharTypeBuffer<T>::CharType CharType;
+
+    wxWritableCharTypeBuffer(const wxCharTypeBuffer<T>& src)
+        : wxCharTypeBuffer<T>(src) {}
+    // FIXME-UTF8: this won't be needed after converting mb_str()/wc_str() to
+    //             always return a buffer
+    wxWritableCharTypeBuffer(const CharType *str = NULL)
+        : wxCharTypeBuffer<T>(str) {}
+
+    operator CharType*() { return this->data(); }
+};
+
+typedef wxWritableCharTypeBuffer<char> wxWritableCharBuffer;
+typedef wxWritableCharTypeBuffer<wchar_t> wxWritableWCharBuffer;
+
 
 #if wxUSE_UNICODE
+    #define wxWxCharBuffer wxWCharBuffer
+
     #define wxMB2WXbuf wxWCharBuffer
     #define wxWX2MBbuf wxCharBuffer
-    #define wxWC2WXbuf wxChar*
-    #define wxWX2WCbuf wxChar*
+    #if wxUSE_UNICODE_WCHAR
+        #define wxWC2WXbuf wxChar*
+        #define wxWX2WCbuf wxChar*
+    #elif wxUSE_UNICODE_UTF8
+        #define wxWC2WXbuf wxWCharBuffer
+        #define wxWX2WCbuf wxWCharBuffer
+    #endif
 #else // ANSI
+    #define wxWxCharBuffer wxCharBuffer
+
     #define wxMB2WXbuf wxChar*
     #define wxWX2MBbuf wxChar*
     #define wxWC2WXbuf wxCharBuffer
     #define wxWX2WCbuf wxWCharBuffer
 #endif // Unicode/ANSI
 
+// type of the value returned by wxString::utf8_str()
+#if wxUSE_UNICODE_UTF8
+    #define wxUTF8Buf char *
+#else
+    #define wxUTF8Buf wxCharBuffer
+#endif
+
 // ----------------------------------------------------------------------------
 // A class for holding growable data buffers (not necessarily strings)
 // ----------------------------------------------------------------------------
@@ -211,9 +383,12 @@ public:
 
     wxMemoryBuffer& operator=(const wxMemoryBuffer& src)
     {
-        m_bufdata->DecRef();
-        m_bufdata = src.m_bufdata;
-        m_bufdata->IncRef();
+        if (&src != this)
+        {
+            m_bufdata->DecRef();
+            m_bufdata = src.m_bufdata;
+            m_bufdata->IncRef();
+        }
         return *this;
     }