X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/f6bcfd974ef26faf6f91a62cac09827e09463fd1..1a2fe0cbea671f0642b71f0a3ea30a55943e21c5:/include/wx/buffer.h

diff --git a/include/wx/buffer.h b/include/wx/buffer.h
index 6556f39cd6..3d7d6403f6 100644
--- a/include/wx/buffer.h
+++ b/include/wx/buffer.h
@@ -1,130 +1,375 @@
 ///////////////////////////////////////////////////////////////////////////////
-// Name:        buffer.h
+// Name:        wx/buffer.h
 // Purpose:     auto buffer classes: buffers which automatically free memory
 // Author:      Vadim Zeitlin
 // Modified by:
 // Created:     12.04.99
 // RCS-ID:      $Id$
 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
-// Licence:     wxWindows license
+// Licence:     wxWindows licence
 ///////////////////////////////////////////////////////////////////////////////
 
-// these classes are for private use only for now, they're not documented
-
 #ifndef _WX_BUFFER_H
 #define _WX_BUFFER_H
 
-#include "wx/wxchar.h"
+#include "wx/chartype.h"
+#include "wx/wxcrtbase.h"
+
+#include <stdlib.h>             // malloc() and free()
 
-#include <string.h> // strdup
+class WXDLLIMPEXP_FWD_BASE wxCStrData;
 
 // ----------------------------------------------------------------------------
 // Special classes for (wide) character strings: they use malloc/free instead
 // of new/delete
 // ----------------------------------------------------------------------------
 
-class wxCharBuffer
+template <typename T>
+class wxCharTypeBuffer
 {
 public:
-    wxCharBuffer(const char *str)
+    typedef T CharType;
+
+    wxCharTypeBuffer(const CharType *str = NULL)
+        : m_str(str ? wxStrdup(str) : NULL),
+          m_owned(true)
     {
-        wxASSERT_MSG( str, wxT("NULL string in wxCharBuffer") );
+    }
 
-        m_str = str ? strdup(str) : (char *)NULL;
+    wxCharTypeBuffer(size_t len)
+        : m_str((CharType *)malloc((len + 1)*sizeof(CharType))),
+          m_owned(true)
+    {
+        m_str[len] = (CharType)0;
     }
-    wxCharBuffer(size_t len)
+
+    static const wxCharTypeBuffer CreateNonOwned(const CharType *str)
+    {
+        wxCharTypeBuffer buf;
+        buf.m_str = wx_const_cast(CharType*, str);
+        buf.m_owned = false;
+        return buf;
+    }
+
+    /* no need to check for NULL, free() does it */
+    ~wxCharTypeBuffer()
     {
-        m_str = (char *)malloc(len+1);
-        m_str[len] = '\0';
+        if ( m_owned)
+            free(m_str);
     }
-    // no need to check for NULL, free() does it
-   ~wxCharBuffer() { free(m_str); }
 
-   wxCharBuffer(const wxCharBuffer& src)
-   {
-     m_str = src.m_str;
-     // no reference count yet...
-     ((wxCharBuffer*)&src)->m_str = (char *)NULL;
-   }
-   wxCharBuffer& operator=(const wxCharBuffer& src)
-   {
-     m_str = src.m_str;
-     // no reference count yet...
-     ((wxCharBuffer*)&src)->m_str = (char *)NULL;
-     return *this;
-   }
+    /*
+        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 wxCharTypeBuffer 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
+    {
+        wxASSERT_MSG( m_owned, _T("can't release non-owned buffer") );
+        return DoRelease();
+    }
+
+    void reset()
+    {
+        if ( m_owned )
+            free(m_str);
+        m_str = NULL;
+    }
+
+    wxCharTypeBuffer(const wxCharTypeBuffer& src)
+    {
+        CopyFrom(src);
+    }
+
+    wxCharTypeBuffer& operator=(const CharType *str)
+    {
+        if ( m_owned )
+            free(m_str);
+        m_str = str ? wxStrdup(str) : NULL;
+        m_owned = true;
+        return *this;
+    }
+
+    wxCharTypeBuffer& operator=(const wxCharTypeBuffer& src)
+    {
+        if ( m_owned )
+            free(m_str);
+        CopyFrom(src);
+        return *this;
+    }
+
+    bool extend(size_t len)
+    {
+        wxASSERT_MSG( m_owned, _T("cannot extend non-owned buffer") );
+
+        CharType *
+            str = (CharType *)realloc(m_str, (len + 1)*sizeof(CharType));
+        if ( !str )
+            return false;
+
+        m_str = str;
+
+        return true;
+    }
 
-   const char *data() const { return m_str; }
-   operator const char *() const { return m_str; }
-   char operator[](size_t n) const { return m_str[n]; }
+    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 *DoRelease() const
+    {
+        CharType *p = m_str;
+        ((wxCharTypeBuffer *)this)->m_str = NULL;
+        return p;
+    }
+
+    void CopyFrom(const wxCharTypeBuffer& src)
+    {
+        m_owned = src.m_owned;
+        m_str = src.DoRelease();
+    }
 
 private:
-   char *m_str;
+    CharType *m_str;
+    bool m_owned;
+};
+
+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
-class wxWCharBuffer
+class wxWCharBuffer : public wxCharTypeBuffer<wchar_t>
 {
 public:
-    wxWCharBuffer(const wchar_t *wcs)
-    {
-        wxASSERT_MSG( wcs, wxT("NULL string in wxWCharBuffer") );
-
-        if (wcs) {
-#if (defined(__BORLANDC__) && (__BORLANDC__ > 0x530))
-          size_t siz = (std::wcslen(wcs)+1)*sizeof(wchar_t);
-#else
-          size_t siz = (::wcslen(wcs)+1)*sizeof(wchar_t);
-#endif
-          m_wcs = (wchar_t *)malloc(siz);
-          memcpy(m_wcs, wcs, siz);
-        }
-        else m_wcs = (wchar_t *)NULL;
-    }
-    wxWCharBuffer(size_t len)
-    {
-        m_wcs = (wchar_t *)malloc((len+1)*sizeof(wchar_t));
-        m_wcs[len] = L'\0';
-    }
+    typedef wxCharTypeBuffer<wchar_t> wxCharTypeBufferBase;
+
+    wxWCharBuffer(const wxCharTypeBufferBase& buf)
+        : wxCharTypeBufferBase(buf) {}
 
-    // no need to check for NULL, free() does it
-   ~wxWCharBuffer() { free(m_wcs); }
+    wxWCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {}
+    wxWCharBuffer(size_t len) : wxCharTypeBufferBase(len) {}
 
-   wxWCharBuffer(const wxWCharBuffer& src)
-   {
-     m_wcs = src.m_wcs;
-     // no reference count yet...
-     ((wxWCharBuffer*)&src)->m_wcs = (wchar_t *)NULL;
-   }
-   wxWCharBuffer& operator=(const wxWCharBuffer& src)
-   {
-     m_wcs = src.m_wcs;
-     // no reference count yet...
-     ((wxWCharBuffer*)&src)->m_wcs = (wchar_t *)NULL;
-     return *this;
-   }
+    wxWCharBuffer(const wxCStrData& cstr);
+};
+#endif // wxUSE_WCHAR_T
 
-   const wchar_t *data() const { return m_wcs; }
-   operator const wchar_t *() const { return m_wcs; }
-   wchar_t operator[](size_t n) const { return m_wcs[n]; }
+// wxCharTypeBuffer<T> implicitly convertible to T*
+template <typename T>
+class wxWritableCharTypeBuffer : public wxCharTypeBuffer<T>
+{
+public:
+    typedef typename wxCharTypeBuffer<T>::CharType CharType;
 
-private:
-   wchar_t *m_wcs;
+    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(); }
 };
-#endif
+
+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
 
+// ----------------------------------------------------------------------------
+// A class for holding growable data buffers (not necessarily strings)
+// ----------------------------------------------------------------------------
+
+// This class manages the actual data buffer pointer and is ref-counted.
+class wxMemoryBufferData
+{
+public:
+    // the initial size and also the size added by ResizeIfNeeded()
+    enum { DefBufSize = 1024 };
+
+    friend class wxMemoryBuffer;
+
+    // everyting is private as it can only be used by wxMemoryBuffer
+private:
+    wxMemoryBufferData(size_t size = wxMemoryBufferData::DefBufSize)
+        : m_data(size ? malloc(size) : NULL), m_size(size), m_len(0), m_ref(0)
+    {
+    }
+    ~wxMemoryBufferData() { free(m_data); }
+
+
+    void ResizeIfNeeded(size_t newSize)
+    {
+        if (newSize > m_size)
+        {
+            void *dataOld = m_data;
+            m_data = realloc(m_data, newSize + wxMemoryBufferData::DefBufSize);
+            if ( !m_data )
+            {
+                free(dataOld);
+            }
+
+            m_size = newSize + wxMemoryBufferData::DefBufSize;
+        }
+    }
+
+    void IncRef() { m_ref += 1; }
+    void DecRef()
+    {
+        m_ref -= 1;
+        if (m_ref == 0)  // are there no more references?
+            delete this;
+    }
+
+
+    // the buffer containing the data
+    void  *m_data;
+
+    // the size of the buffer
+    size_t m_size;
+
+    // the amount of data currently in the buffer
+    size_t m_len;
+
+    // the reference count
+    size_t m_ref;
+
+    DECLARE_NO_COPY_CLASS(wxMemoryBufferData)
+};
+
+
+class wxMemoryBuffer
+{
+public:
+    // ctor and dtor
+    wxMemoryBuffer(size_t size = wxMemoryBufferData::DefBufSize)
+    {
+        m_bufdata = new wxMemoryBufferData(size);
+        m_bufdata->IncRef();
+    }
+
+    ~wxMemoryBuffer() { m_bufdata->DecRef(); }
+
+
+    // copy and assignment
+    wxMemoryBuffer(const wxMemoryBuffer& src)
+        : m_bufdata(src.m_bufdata)
+    {
+        m_bufdata->IncRef();
+    }
+
+    wxMemoryBuffer& operator=(const wxMemoryBuffer& src)
+    {
+        m_bufdata->DecRef();
+        m_bufdata = src.m_bufdata;
+        m_bufdata->IncRef();
+        return *this;
+    }
+
+
+    // Accessors
+    void  *GetData() const    { return m_bufdata->m_data; }
+    size_t GetBufSize() const { return m_bufdata->m_size; }
+    size_t GetDataLen() const { return m_bufdata->m_len; }
+
+    void   SetBufSize(size_t size) { m_bufdata->ResizeIfNeeded(size); }
+    void   SetDataLen(size_t len)
+    {
+        wxASSERT(len <= m_bufdata->m_size);
+        m_bufdata->m_len = len;
+    }
+
+    // Ensure the buffer is big enough and return a pointer to it
+    void *GetWriteBuf(size_t sizeNeeded)
+    {
+        m_bufdata->ResizeIfNeeded(sizeNeeded);
+        return m_bufdata->m_data;
+    }
+
+    // Update the length after the write
+    void  UngetWriteBuf(size_t sizeUsed) { SetDataLen(sizeUsed); }
+
+    // Like the above, but appends to the buffer
+    void *GetAppendBuf(size_t sizeNeeded)
+    {
+        m_bufdata->ResizeIfNeeded(m_bufdata->m_len + sizeNeeded);
+        return (char*)m_bufdata->m_data + m_bufdata->m_len;
+    }
+
+    // Update the length after the append
+    void  UngetAppendBuf(size_t sizeUsed)
+    {
+        SetDataLen(m_bufdata->m_len + sizeUsed);
+    }
+
+    // Other ways to append to the buffer
+    void  AppendByte(char data)
+    {
+        wxCHECK_RET( m_bufdata->m_data, _T("invalid wxMemoryBuffer") );
+
+        m_bufdata->ResizeIfNeeded(m_bufdata->m_len + 1);
+        *(((char*)m_bufdata->m_data) + m_bufdata->m_len) = data;
+        m_bufdata->m_len += 1;
+    }
+
+    void  AppendData(const void *data, size_t len)
+    {
+        memcpy(GetAppendBuf(len), data, len);
+        UngetAppendBuf(len);
+    }
+
+    operator const char *() const { return (const char*)GetData(); }
+
+private:
+    wxMemoryBufferData*  m_bufdata;
+};
+
 // ----------------------------------------------------------------------------
 // template class for any kind of data
 // ----------------------------------------------------------------------------