X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/7a3e402c11cee61059e515e8a82d52fe285e69b7..d51305e81eb593bedd92cda864671e15209c268f:/include/wx/buffer.h

diff --git a/include/wx/buffer.h b/include/wx/buffer.h
index 67d23526d6..976177e3f1 100644
--- a/include/wx/buffer.h
+++ b/include/wx/buffer.h
@@ -1,120 +1,267 @@
 ///////////////////////////////////////////////////////////////////////////////
-// 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 <string.h> // strdup
+
+#include <stdlib.h>             // malloc() and free()
 
 // ----------------------------------------------------------------------------
 // Special classes for (wide) character strings: they use malloc/free instead
 // of new/delete
 // ----------------------------------------------------------------------------
 
-class wxCharBuffer
+#define DEFINE_BUFFER(classname, chartype, strdupfunc)                      \
+class WXDLLIMPEXP_BASE classname                                            \
+{                                                                           \
+public:                                                                     \
+    classname(const chartype *str)                                          \
+        : 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;                                                       \
+    }                                                                       \
+                                                                            \
+    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);
+
+#if wxUSE_WCHAR_T
+
+DEFINE_BUFFER(wxWCharBuffer, wchar_t, wxStrdupW);
+
+#endif // wxUSE_WCHAR_T
+
+#undef DEFINE_BUFFER
+
+#if wxUSE_UNICODE
+    #define wxMB2WXbuf wxWCharBuffer
+    #define wxWX2MBbuf wxCharBuffer
+    #define wxWC2WXbuf wxChar*
+    #define wxWX2WCbuf wxChar*
+#else // ANSI
+    #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:
-    wxCharBuffer(const char *str)
+    // the initial size and also the size added by ResizeIfNeeded()
+    enum { BLOCK_SIZE = 1024 };
+
+    friend class wxMemoryBuffer;
+
+    // everyting is private as it can only be used by wxMemoryBuffer
+private:
+    wxMemoryBufferData(size_t size = wxMemoryBufferData::BLOCK_SIZE)
+        : m_data(size ? malloc(size) : NULL), m_size(size), m_len(0), m_ref(0)
+    {
+    }
+    ~wxMemoryBufferData() { free(m_data); }
+
+
+    void ResizeIfNeeded(size_t newSize)
     {
-        wxASSERT_MSG( str, _T("NULL string in wxCharBuffer") );
+        if (newSize > m_size)
+        {
+            void *dataOld = m_data;
+            m_data = realloc(m_data, newSize + wxMemoryBufferData::BLOCK_SIZE);
+            if ( !m_data )
+            {
+                free(dataOld);
+            }
 
-        m_str = str ? strdup(str) : (char *)NULL;
+            m_size = newSize + wxMemoryBufferData::BLOCK_SIZE;
+        }
     }
-    wxCharBuffer(size_t len)
+
+    void IncRef() { m_ref += 1; }
+    void DecRef()
     {
-        m_str = (char *)malloc(len+1);
-	m_str[len] = '\0';
+        m_ref -= 1;
+        if (m_ref == 0)  // are there no more references?
+            delete this;
     }
-    // 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;
-   }
-
-   operator const char *() const { return m_str; }
 
-private:
-   char *m_str;
+
+    // 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)
 };
 
-#if wxUSE_WCHAR_T
-class wxWCharBuffer
+
+class wxMemoryBuffer
 {
 public:
-    wxWCharBuffer(const wchar_t *wcs)
+    // ctor and dtor
+    wxMemoryBuffer(size_t size = wxMemoryBufferData::BLOCK_SIZE)
     {
-        wxASSERT_MSG( wcs, _T("NULL string in wxWCharBuffer") );
+        m_bufdata = new wxMemoryBufferData(size);
+        m_bufdata->IncRef();
+    }
 
-        if (wcs) {
-          size_t siz = (wcslen(wcs)+1)*sizeof(wchar_t);
-          m_wcs = (wchar_t *)malloc(siz);
-          memcpy(m_wcs, wcs, siz);
-        }
-        else m_wcs = (wchar_t *)NULL;
+    ~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;
     }
-    wxWCharBuffer(size_t len)
+
+    // Update the length after the append
+    void  UngetAppendBuf(size_t sizeUsed)
     {
-        m_wcs = (wchar_t *)malloc((len+1)*sizeof(wchar_t));
-	m_wcs[len] = L'\0';
+        SetDataLen(m_bufdata->m_len + sizeUsed);
     }
 
-    // no need to check for NULL, free() does it
-   ~wxWCharBuffer() { free(m_wcs); }
-
-   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;
-   }
-
-   operator const wchar_t *() const { return m_wcs; }
+    // 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(void* data, size_t len)
+    {
+        memcpy(GetAppendBuf(len), data, len);
+        UngetAppendBuf(len);
+    }
+
+    operator const char *() const { return (const char*)GetData(); }
 
 private:
-   wchar_t *m_wcs;
+    wxMemoryBufferData*  m_bufdata;
 };
-#endif
-
-#if wxUSE_UNICODE
-#define wxMB2WXbuf wxWCharBuffer
-#define wxWX2MBbuf wxCharBuffer
-#define wxWC2WXbuf wxChar*
-#define wxWX2WCbuf wxChar*
-#else
-#define wxMB2WXbuf wxChar*
-#define wxWX2MBbuf wxChar*
-#define wxWC2WXbuf wxCharBuffer
-#define wxWX2WCbuf wxWCharBuffer
-#endif
 
 // ----------------------------------------------------------------------------
 // template class for any kind of data