///////////////////////////////////////////////////////////////////////////////
-// 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 <string.h> // strdup
-#include <wchar.h> // wchar_t
+#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
// ----------------------------------------------------------------------------
-class wxCharBuffer
+// helpers used by wxCharTypeBuffer
+namespace wxPrivate
+{
+
+struct UntypedBufferData
+{
+ enum Kind
+ {
+ Owned,
+ NonOwned
+ };
+
+ UntypedBufferData(void *str, size_t len, Kind kind = Owned)
+ : m_str(str), m_length(len), m_ref(1), m_owned(kind == Owned) {}
+
+ ~UntypedBufferData()
+ {
+ if ( m_owned )
+ free(m_str);
+ }
+
+ void *m_str;
+ size_t m_length;
+
+ // "short" to have sizeof(Data)=12 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
+
+
+// Reference-counted character buffer for storing string data. The buffer
+// is only valid for as long as the "parent" object that provided the data
+// is valid; see wxCharTypeBuffer<T> for persistent variant.
+template <typename T>
+class wxScopedCharTypeBuffer
{
public:
- wxCharBuffer(const char *str)
+ typedef T CharType;
+
+ wxScopedCharTypeBuffer()
+ {
+ m_data = GetNullData();
+ }
+
+ // Creates "non-owned" buffer, i.e. 'str' is not owned by the buffer
+ // and doesn't get freed by dtor. Used e.g. to point to wxString's internal
+ // storage.
+ static
+ const wxScopedCharTypeBuffer CreateNonOwned(const CharType *str,
+ size_t len = wxNO_LEN)
{
- wxASSERT_MSG( str, _T("NULL string in wxCharBuffer") );
+ if ( len == wxNO_LEN )
+ len = wxStrlen(str);
- m_str = str ? strdup(str) : (char *)NULL;
+ wxScopedCharTypeBuffer buf;
+ if ( str )
+ buf.m_data = new Data(const_cast<CharType*>(str), len, Data::NonOwned);
+ return buf;
}
- wxCharBuffer(size_t len)
+
+ // Creates "owned" buffer, i.e. takes over ownership of 'str' and frees it
+ // in dtor (if ref.count reaches 0).
+ static
+ const wxScopedCharTypeBuffer CreateOwned(const CharType *str,
+ size_t len = wxNO_LEN )
{
- m_str = (char *)malloc(len+1);
- m_str[len] = '\0';
+ if ( len == wxNO_LEN )
+ len = wxStrlen(str);
+
+ wxScopedCharTypeBuffer buf;
+ if ( str )
+ buf.m_data = new Data(StrCopy(str, len), len);
+ return buf;
}
- // 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;
- }
+ wxScopedCharTypeBuffer(const wxScopedCharTypeBuffer& src)
+ {
+ m_data = src.m_data;
+ IncRef();
+ }
- operator const char *() const { return m_str; }
+ wxScopedCharTypeBuffer& operator=(const wxScopedCharTypeBuffer& src)
+ {
+ if ( &src == this )
+ return *this;
-private:
- char *m_str;
+ DecRef();
+ m_data = src.m_data;
+ IncRef();
+
+ return *this;
+ }
+
+ ~wxScopedCharTypeBuffer()
+ {
+ 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();
+
+ wxScopedCharTypeBuffer *self = const_cast<wxScopedCharTypeBuffer*>(this);
+ self->m_data->Set(NULL, 0);
+ self->DecRef();
+
+ return p;
+ }
+
+ void reset()
+ {
+ DecRef();
+ }
+
+ 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]; }
+
+ size_t length() const { return m_data->m_length; }
+
+protected:
+ // reference-counted data
+ struct Data : public wxPrivate::UntypedBufferData
+ {
+ Data(CharType *str, size_t len, Kind kind = Owned)
+ : wxPrivate::UntypedBufferData(str, len, kind)
+ {
+ }
+
+ CharType *Get() const { return static_cast<CharType *>(m_str); }
+ void Set(CharType *str, size_t len)
+ {
+ m_str = str;
+ m_length = len;
+ }
+ };
+
+ // 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();
+ }
+
+ // sets this object to a be copy of 'other'; if 'src' is non-owned,
+ // a deep copy is made and 'this' will contain new instance of the data
+ void MakeOwnedCopyOf(const wxScopedCharTypeBuffer& src)
+ {
+ this->DecRef();
+
+ if ( src.m_data == this->GetNullData() )
+ {
+ this->m_data = this->GetNullData();
+ }
+ else if ( src.m_data->m_owned )
+ {
+ this->m_data = src.m_data;
+ this->IncRef();
+ }
+ else
+ {
+ // if the scoped buffer had non-owned data, we have to make
+ // a copy here, because src.m_data->m_str is valid only for as long
+ // as 'src' exists
+ this->m_data = new Data
+ (
+ StrCopy(src.data(), src.length()),
+ src.length()
+ );
+ }
+ }
+
+ static CharType *StrCopy(const CharType *src, size_t len)
+ {
+ CharType *dst = (CharType*)malloc(sizeof(CharType) * (len + 1));
+ memcpy(dst, src, sizeof(CharType) * (len + 1));
+ return dst;
+ }
+
+protected:
+ Data *m_data;
};
-class wxWCharBuffer
+typedef wxScopedCharTypeBuffer<char> wxScopedCharBuffer;
+typedef wxScopedCharTypeBuffer<wchar_t> wxScopedWCharBuffer;
+
+
+// this buffer class always stores data in "owned" (persistent) manner
+template <typename T>
+class wxCharTypeBuffer : public wxScopedCharTypeBuffer<T>
{
+protected:
+ typedef typename wxScopedCharTypeBuffer<T>::Data Data;
+
public:
- wxWCharBuffer(const wchar_t *wcs)
+ typedef T CharType;
+
+ wxCharTypeBuffer(const CharType *str = NULL, size_t len = wxNO_LEN)
{
- wxASSERT_MSG( wcs, _T("NULL string in wxWCharBuffer") );
+ if ( str )
+ {
+ if ( len == wxNO_LEN )
+ len = wxStrlen(str);
+ this->m_data = new Data(StrCopy(str, len), len);
+ }
+ else
+ {
+ this->m_data = this->GetNullData();
+ }
+ }
- m_wcs = wcs ? (wchar_t *)malloc((wcslen(wcs)+1)*sizeof(wchar_t))
- : (wchar_t *)NULL;
- if (m_wcs) wcscpy(m_wcs, wcs);
+ wxCharTypeBuffer(size_t len)
+ {
+ this->m_data =
+ new Data((CharType *)malloc((len + 1)*sizeof(CharType)), len);
+ this->m_data->Get()[len] = (CharType)0;
}
- wxWCharBuffer(size_t len)
+
+ wxCharTypeBuffer(const wxCharTypeBuffer& src)
+ : wxScopedCharTypeBuffer<T>(src) {}
+
+ wxCharTypeBuffer& operator=(const CharType *str)
{
- m_wcs = (wchar_t *)malloc((len+1)*sizeof(wchar_t));
- m_wcs[len] = L'\0';
+ this->DecRef();
+
+ if ( str )
+ this->m_data = new Data(wxStrdup(str), wxStrlen(str));
+ return *this;
}
- // no need to check for NULL, free() does it
- ~wxWCharBuffer() { free(m_wcs); }
+ wxCharTypeBuffer& operator=(const wxCharTypeBuffer& src)
+ {
+ wxScopedCharTypeBuffer<T>::operator=(src);
+ return *this;
+ }
- 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;
- }
+ wxCharTypeBuffer(const wxScopedCharTypeBuffer<T>& src)
+ {
+ MakeOwnedCopyOf(src);
+ }
- operator const wchar_t *() const { return m_wcs; }
+ wxCharTypeBuffer& operator=(const wxScopedCharTypeBuffer<T>& src)
+ {
+ MakeOwnedCopyOf(src);
+ return *this;
+ }
-private:
- wchar_t *m_wcs;
+ bool extend(size_t len)
+ {
+ wxASSERT_MSG( this->m_data->m_owned, "cannot extend non-owned buffer" );
+ wxASSERT_MSG( this->m_data->m_ref == 1, "can't extend shared buffer" );
+
+ CharType *str =
+ (CharType *)realloc(this->data(), (len + 1) * sizeof(CharType));
+ if ( !str )
+ return false;
+
+ if ( this->m_data == this->GetNullData() )
+ {
+ this->m_data = new Data(str, len);
+ }
+ else
+ {
+ this->m_data->Set(str, len);
+ this->m_data->m_owned = true;
+ }
+
+ return true;
+ }
+
+ void shrink(size_t len)
+ {
+ wxASSERT_MSG( this->m_data->m_owned, "cannot shrink non-owned buffer" );
+ wxASSERT_MSG( this->m_data->m_ref == 1, "can't shrink shared buffer" );
+
+ wxASSERT( len <= this->length() );
+
+ this->m_data->m_length = len;
+ this->data()[len] = 0;
+ }
};
+WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxScopedCharTypeBuffer<char> )
+WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxCharTypeBuffer<char> )
+
+class wxCharBuffer : public wxCharTypeBuffer<char>
+{
+public:
+ typedef wxCharTypeBuffer<char> wxCharTypeBufferBase;
+ typedef wxScopedCharTypeBuffer<char> wxScopedCharTypeBufferBase;
+
+ wxCharBuffer(const wxCharTypeBufferBase& buf)
+ : wxCharTypeBufferBase(buf) {}
+ wxCharBuffer(const wxScopedCharTypeBufferBase& 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( wxScopedCharTypeBuffer<wchar_t> )
+WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxCharTypeBuffer<wchar_t> )
+
+class wxWCharBuffer : public wxCharTypeBuffer<wchar_t>
+{
+public:
+ typedef wxCharTypeBuffer<wchar_t> wxCharTypeBufferBase;
+ typedef wxScopedCharTypeBuffer<wchar_t> wxScopedCharTypeBufferBase;
+
+ wxWCharBuffer(const wxCharTypeBufferBase& buf)
+ : wxCharTypeBufferBase(buf) {}
+ wxWCharBuffer(const wxScopedCharTypeBufferBase& buf)
+ : wxCharTypeBufferBase(buf) {}
+
+ wxWCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {}
+ wxWCharBuffer(size_t len) : wxCharTypeBufferBase(len) {}
+
+ wxWCharBuffer(const wxCStrData& cstr);
+};
+#endif // wxUSE_WCHAR_T
+
+// wxCharTypeBuffer<T> implicitly convertible to T*
+template <typename T>
+class wxWritableCharTypeBuffer : public wxCharTypeBuffer<T>
+{
+public:
+ typedef typename wxScopedCharTypeBuffer<T>::CharType CharType;
+
+ wxWritableCharTypeBuffer(const wxScopedCharTypeBuffer<T>& src)
+ : wxCharTypeBuffer<T>(src) {}
+ // FIXME-UTF8: this won't be needed after converting mb_str()/wc_str() to
+ // always return a buffer
+ // + we should derive this class from wxScopedCharTypeBuffer
+ // then
+ 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 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
+ #define wxWxCharBuffer wxWCharBuffer
+
+ #define wxMB2WXbuf wxWCharBuffer
+ #define wxWX2MBbuf wxCharBuffer
+ #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;
+
+ wxDECLARE_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)
+ {
+ if (&src != this)
+ {
+ 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