Added tests for buffered streams.

Made wxBufferedOutputStream call Sync() in
    the destructor and SeekO().
  Documented this.
  Use buffered streams in wxImage. Seems to
    significantly speed-up the sample.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@4847 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

docs/latex/wx/strmbfrd.tex

@@ -28,8 +28,9 @@ from (such as a file stream or a memory stream).
 
 This stream acts as a cache. It caches the bytes to be written to the specified
 output stream (See \helpref{wxFilterOutputStream}{wxfilteroutputstream}). The
-datas are only written when the cache is full or when the buffered stream is
+datas are only written when the cache is full, when the buffered stream is
-destroyed.
+destroyed or when calling SeekO().
+
 This class may not be used without some other stream to write the data
 to (such as a file stream or a memory stream).
 
@@ -45,3 +46,35 @@ to (such as a file stream or a memory stream).
 
 \helpref{wxStreamBuffer}{wxstreamBuffer}, \helpref{wxOutputStream}{wxoutputstream}
 
+% ----------
+% Members
+% ----------
+\latexignore{\rtfignore{\wxheading{Members}}}
+
+\membersection{wxBufferedOutputStream::wxBufferedOutputStream}
+
+\func{}{wxBufferedOutputStream}{\param{const wxOutputStream\&}{ parent}}
+
+Creates a buffered stream using a buffer of a default size of 1024 bytes for cashing
+the stream {\it parent}.
+
+\membersection{wxBufferedOutputStream::\destruct{wxBufferedOutputStream}}
+
+\func{}{\destruct{wxBufferedOutputStream}}{\void}
+
+Destructor. Calls Sync() and destroys the internal buffer.
+
+\membersection{wxBufferedOutputStream::SeekO}
+
+\func{off\_t}{SeekO}{\param{off\_t}{ pos}, \param{wxSeekMode}{ mode}}
+
+Calls Sync() and changes the stream position.
+
+\membersection{wxBufferedOutputStream::Sync}
+
+\func{void}{Sync}{\void}
+
+Flushes the buffer and calls Sync() on the parent stream.
+
+
+

samples/typetest/typetest.cpp

@@ -60,6 +60,7 @@ BEGIN_EVENT_TABLE(MyApp, wxApp)
 #if wxUSE_UNICODE
     EVT_MENU(TYPES_UNICODE,   MyApp::DoUnicodeDemo)
 #endif
+    EVT_MENU(TYPES_STREAM2, MyApp::DoStreamDemo2)
     EVT_MENU(TYPES_STREAM, MyApp::DoStreamDemo)
     EVT_MENU(TYPES_MIME, MyApp::DoMIMEDemo)
 END_EVENT_TABLE()
@@ -89,6 +90,7 @@ bool MyApp::OnInit()
     test_menu->Append(TYPES_UNICODE, "&Unicode test");
 #endif
     test_menu->Append(TYPES_STREAM, "&Stream test");
+    test_menu->Append(TYPES_STREAM2, "&Stream seek test");
     test_menu->AppendSeparator();
     test_menu->Append(TYPES_MIME, "&MIME database test");
 
@@ -256,6 +258,78 @@ void MyApp::DoStreamDemo(wxCommandEvent& WXUNUSED(event))
     textCtrl.WriteText( tmp );
 }
 
+void MyApp::DoStreamDemo2(wxCommandEvent& WXUNUSED(event))
+{
+    wxTextCtrl& textCtrl = * GetTextCtrl();
+
+    textCtrl.Clear();
+    textCtrl << _T("\nTest wxBufferedStream:\n\n");
+
+    char ch,ch2;
+
+    textCtrl.WriteText( "Writing number 0 to 9 to buffered wxFileOutputStream:\n\n" );
+
+    wxFileOutputStream file_output( "test_wx.dat" );
+    wxBufferedOutputStream buf_output( file_output );
+    for (ch = 0; ch < 10; ch++)
+        buf_output.Write( &ch, 1 );
+    buf_output.Sync();
+    
+    wxFileInputStream file_input( "test_wx.dat" );
+    for (ch2 = 0; ch2 < 10; ch2++)
+    {
+        file_input.Read( &ch, 1 );
+	textCtrl.WriteText( (char)(ch + '0') );
+    }
+    textCtrl.WriteText( "\n\n\n" );
+    
+    textCtrl.WriteText( "Writing number 0 to 9 to buffered wxFileOutputStream, then\n" );
+    textCtrl.WriteText( "seeking back to #3 and writing 3:\n\n" );
+
+    wxFileOutputStream file_output2( "test_wx2.dat" );
+    wxBufferedOutputStream buf_output2( file_output2 );
+    for (ch = 0; ch < 10; ch++)
+        buf_output2.Write( &ch, 1 );
+    buf_output2.SeekO( 3 );
+    ch = 3;
+    buf_output2.Write( &ch, 1 );
+    buf_output2.Sync();
+    
+    wxFileInputStream file_input2( "test_wx2.dat" );
+    for (ch2 = 0; ch2 < 10; ch2++)
+    {
+        file_input2.Read( &ch, 1 );
+	textCtrl.WriteText( (char)(ch + '0') );
+    }
+    textCtrl.WriteText( "\n\n\n" );
+    
+    // now append 2000 bytes to file (bigger than buffer)
+    buf_output2.SeekO( 0, wxFromEnd );
+    ch = 1;
+    for (int i = 0; i < 2000; i++)
+       buf_output2.Write( &ch, 1 );
+    buf_output2.Sync();
+    
+    textCtrl.WriteText( "Reading number 0 to 9 from buffered wxFileInputStream, then\n" );
+    textCtrl.WriteText( "seeking back to #3 and reading 3:\n\n" );
+
+    wxFileInputStream file_input3( "test_wx2.dat" );
+    wxBufferedInputStream buf_input3( file_input3 );
+    for (ch2 = 0; ch2 < 10; ch2++)
+    {
+        buf_input3.Read( &ch, 1 );
+	textCtrl.WriteText( (char)(ch + '0') );
+    }
+    for (int j = 0; j < 2000; j++)
+       buf_input3.Read( &ch, 1 );
+    textCtrl.WriteText( "\n" );
+    buf_input3.SeekI( 3 );
+    buf_input3.Read( &ch, 1 );
+    textCtrl.WriteText( (char)(ch + '0') );
+    textCtrl.WriteText( "\n\n\n" );
+    
+}
+
 #if wxUSE_UNICODE
 void MyApp::DoUnicodeDemo(wxCommandEvent& WXUNUSED(event))
 {

samples/typetest/typetest.h

@@ -30,6 +30,7 @@ public:
     void DoVariantDemo(wxCommandEvent& event);
     void DoByteOrderDemo(wxCommandEvent& event);
     void DoStreamDemo(wxCommandEvent& event);
+    void DoStreamDemo2(wxCommandEvent& event);
 #if wxUSE_UNICODE
     void DoUnicodeDemo(wxCommandEvent& event);
 #endif
@@ -74,6 +75,7 @@ enum
     TYPES_BYTEORDER,
     TYPES_UNICODE,
     TYPES_STREAM,
+    TYPES_STREAM2,
     TYPES_MIME
 };
 

src/common/image.cpp

@@ -381,7 +381,8 @@ bool wxImage::LoadFile( const wxString& filename, long type )
     if (wxFileExists(filename))
     {
         wxFileInputStream stream(filename);
-        return LoadFile(stream, type);
+	wxBufferedInputStream bstream( stream );
+        return LoadFile(bstream, type);
     }
     else 
     {
@@ -400,7 +401,8 @@ bool wxImage::LoadFile( const wxString& filename, const wxString& mimetype )
     if (wxFileExists(filename))
     {
         wxFileInputStream stream(filename);
-        return LoadFile(stream, mimetype);
+	wxBufferedInputStream bstream( stream );
+        return LoadFile(bstream, mimetype);
     }
     else 
     {
@@ -419,7 +421,10 @@ bool wxImage::SaveFile( const wxString& filename, int type )
     wxFileOutputStream stream(filename);
 
     if ( stream.LastError() == wxStream_NOERROR )
-        return SaveFile(stream, type);
+    {
+	wxBufferedOutputStream bstream( stream );
+        return SaveFile(bstream, type);
+    }
     else
 #endif // wxUSE_STREAMS
         return FALSE;
@@ -431,7 +436,10 @@ bool wxImage::SaveFile( const wxString& filename, const wxString& mimetype )
     wxFileOutputStream stream(filename);
 
     if ( stream.LastError() == wxStream_NOERROR )
-        return SaveFile(stream, mimetype);
+    {
+	wxBufferedOutputStream bstream( stream );
+        return SaveFile(bstream, mimetype);
+    }
     else
 #endif // wxUSE_STREAMS
         return FALSE;

src/common/stream.cpp

@@ -856,6 +856,7 @@ wxBufferedOutputStream::wxBufferedOutputStream(wxOutputStream& s)
 
 wxBufferedOutputStream::~wxBufferedOutputStream()
 {
+  Sync();
   delete m_o_streambuf;
 }
 
@@ -868,6 +869,7 @@ wxOutputStream& wxBufferedOutputStream::Write(const void *buffer, size_t size)
 
 off_t wxBufferedOutputStream::SeekO(off_t pos, wxSeekMode mode)
 {
+  Sync();
   return m_o_streambuf->Seek(pos, mode);
 }