Improve wxImage::LoadImage so that image format in not anymore required

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@3397 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/image.h

@@ -50,8 +50,8 @@ public:
   wxImageHandler() { m_name = ""; m_extension = ""; m_type = 0; }
 
 #if wxUSE_STREAMS
-  virtual bool LoadFile( wxImage *image, wxInputStream& stream );
+  virtual bool LoadFile( wxImage *image, wxInputStream& stream, bool verbose=TRUE );
-  virtual bool SaveFile( wxImage *image, wxOutputStream& stream );
+  virtual bool SaveFile( wxImage *image, wxOutputStream& stream, bool verbose=TRUE );
 #endif
 
   inline void SetName(const wxString& name) { m_name = name; }
@@ -91,8 +91,8 @@ public:
   };
 
 #if wxUSE_STREAMS
-  virtual bool LoadFile( wxImage *image, wxInputStream& stream );
+  virtual bool LoadFile( wxImage *image, wxInputStream& stream, bool verbose=TRUE );
-  virtual bool SaveFile( wxImage *image, wxOutputStream& stream );
+  virtual bool SaveFile( wxImage *image, wxOutputStream& stream, bool verbose=TRUE );
 #endif
 };
 #endif
@@ -117,8 +117,8 @@ public:
   };
 
 #if wxUSE_STREAMS
-  virtual bool LoadFile( wxImage *image, wxInputStream& stream );
+  virtual bool LoadFile( wxImage *image, wxInputStream& stream, bool verbose=TRUE );
-  virtual bool SaveFile( wxImage *image, wxOutputStream& stream );
+  virtual bool SaveFile( wxImage *image, wxOutputStream& stream, bool verbose=TRUE );
 #endif
 };
 #endif
@@ -142,7 +142,7 @@ public:
   };
 
 #if wxUSE_STREAMS
-  virtual bool LoadFile( wxImage *image, wxInputStream& stream );
+  virtual bool LoadFile( wxImage *image, wxInputStream& stream, bool verbose=TRUE );
 #endif
 };
 
@@ -165,8 +165,8 @@ public:
   };
 
 #if wxUSE_STREAMS
-  virtual bool LoadFile( wxImage *image, wxInputStream& stream );
+  virtual bool LoadFile( wxImage *image, wxInputStream& stream, bool verbose=TRUE );
-  virtual bool SaveFile( wxImage *image, wxOutputStream& stream );
+  virtual bool SaveFile( wxImage *image, wxOutputStream& stream, bool verbose=TRUE );
 #endif
 };
 
@@ -184,8 +184,8 @@ public:
 
   wxImage();
   wxImage( int width, int height );
-  wxImage( const wxString& name, long type = wxBITMAP_TYPE_PNG );
+  wxImage( const wxString& name, long type = wxBITMAP_TYPE_ANY );
-  wxImage( wxInputStream& stream, long type = wxBITMAP_TYPE_PNG );
+  wxImage( wxInputStream& stream, long type = wxBITMAP_TYPE_ANY );
   wxImage( const wxString& name, const wxString& mimetype );
   wxImage( wxInputStream& stream, const wxString& mimetype );
 
@@ -212,11 +212,11 @@ public:
   unsigned char GetGreen( int x, int y );
   unsigned char GetBlue( int x, int y );
 
-  virtual bool LoadFile( const wxString& name, long type = wxBITMAP_TYPE_PNG );
+  virtual bool LoadFile( const wxString& name, long type = wxBITMAP_TYPE_ANY );
   virtual bool LoadFile( const wxString& name, const wxString& mimetype );
 
 #if wxUSE_STREAMS
-  virtual bool LoadFile( wxInputStream& stream, long type = wxBITMAP_TYPE_PNG );
+  virtual bool LoadFile( wxInputStream& stream, long type = wxBITMAP_TYPE_ANY );
   virtual bool LoadFile( wxInputStream& stream, const wxString& mimetype );
 #endif
 

src/common/imagbmp.cpp

@@ -64,7 +64,7 @@ IMPLEMENT_DYNAMIC_CLASS(wxBMPHandler,wxImageHandler)
 
 #define poffset (line * width * 3 + column * 3)
 
-bool wxBMPHandler::LoadFile( wxImage *image, wxInputStream& stream )
+bool wxBMPHandler::LoadFile( wxImage *image, wxInputStream& stream, bool WXUNUSED(verbose) )
 {
     int             rshift = 0, gshift = 0, bshift = 0;
     wxUint8         aByte;

src/common/image.cpp

@@ -388,13 +388,41 @@ bool wxImage::SaveFile( const wxString& filename, const wxString& mimetype )
 }
 
 #if wxUSE_STREAMS
+//#include <stream.h>
+
 bool wxImage::LoadFile( wxInputStream& stream, long type )
 {
     UnRef();
 
     m_refData = new wxImageRefData;
 
-    wxImageHandler *handler = FindHandler(type);
+    wxImageHandler *handler;
+
+    if (type==wxBITMAP_TYPE_ANY)
+    {
+      // here we can try to guess the handler according the extension,
+      // but we lose the stream name !?
+      // Probably we should write methods such as 
+      // bool wxImageHandler::IsAppropriate(wxString&)
+      // bool wxImageHandler::IsAppropriate(sxInputStream&&)
+      // for png : see example.c
+	wxList &list=GetHandlers();
+	off_t pos=stream.TellI();
+
+	 wxLogNull prevent_log;
+
+	for ( wxList::Node *node = list.GetFirst(); node; node = node->GetNext() )
+	{
+	    handler=(wxImageHandler*)node->GetData();
+	    //cout << handler->GetExtension() << endl;
+	    if (handler->LoadFile( this, stream, FALSE )) return TRUE;
+	    stream.SeekI(pos);
+	}
+
+	return FALSE;
+    }
+
+    handler = FindHandler(type);
 
     if (handler == NULL)
     {
@@ -563,12 +591,12 @@ IMPLEMENT_DYNAMIC_CLASS(wxImageHandler,wxObject)
 #endif
 
 #if wxUSE_STREAMS
-bool wxImageHandler::LoadFile( wxImage *WXUNUSED(image), wxInputStream& WXUNUSED(stream) )
+bool wxImageHandler::LoadFile( wxImage *WXUNUSED(image), wxInputStream& WXUNUSED(stream), bool WXUNUSED(verbose) )
 {
     return FALSE;
 }
 
-bool wxImageHandler::SaveFile( wxImage *WXUNUSED(image), wxOutputStream& WXUNUSED(stream) )
+bool wxImageHandler::SaveFile( wxImage *WXUNUSED(image), wxOutputStream& WXUNUSED(stream), bool WXUNUSED(verbose) )
 {
     return FALSE;
 }

src/common/imaggif.cpp

@@ -367,7 +367,7 @@ FOLLOWING CODE IS BY V.S. :
 // wxGIFHandler
 //-----------------------------------------------------------------------------
 
-bool wxGIFHandler::LoadFile( wxImage *image, wxInputStream& stream )
+bool wxGIFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool WXUNUSED(verbose) )
 {
     unsigned char *ptr, *src, *pal;
     IMAGEN igif;
@@ -418,9 +418,9 @@ bool wxGIFHandler::LoadFile( wxImage *image, wxInputStream& stream )
 }
 
 bool wxGIFHandler::SaveFile( wxImage * WXUNUSED(image),
-                             wxOutputStream& WXUNUSED(stream) )
+                             wxOutputStream& WXUNUSED(stream), bool verbose )
 {
-    wxLogDebug(_T("wxGIFHandler is read-only!!"));
+    if (verbose) wxLogDebug(_T("wxGIFHandler is read-only!!"));
     return FALSE;
 }
 

src/common/imagjpeg.cpp

@@ -141,7 +141,7 @@ my_error_exit (j_common_ptr cinfo)
 
   /* Always display the message. */
   /* We could postpone this until after returning, if we chose. */
-  (*cinfo->err->output_message) (cinfo);
+  if (cinfo->err->output_message) (*cinfo->err->output_message) (cinfo);
 
   /* Return control to the setjmp point */
   longjmp(myerr->setjmp_buffer, 1);
@@ -149,7 +149,7 @@ my_error_exit (j_common_ptr cinfo)
 
 
 
-bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream )
+bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose )
 {
     struct jpeg_decompress_struct cinfo;
     struct my_error_mgr jerr;
@@ -161,12 +161,14 @@ bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream )
     cinfo.err = jpeg_std_error( &jerr.pub );
     jerr.pub.error_exit = my_error_exit;
 
+    if (!verbose) cinfo.err->output_message=NULL;
+
     /* Establish the setjmp return context for my_error_exit to use. */
     if (setjmp(jerr.setjmp_buffer)) {
       /* If we get here, the JPEG code has signaled an error.
        * We need to clean up the JPEG object, close the input file, and return.
        */
-      wxLogError(_("Couldn't load a JPEG image - probably file is corrupted."));
+      if (verbose) wxLogError(_("Couldn't load a JPEG image - probably file is corrupted."));
       jpeg_destroy_decompress(&cinfo);
       if (image->Ok()) image->Destroy();
       return FALSE;
@@ -263,7 +265,7 @@ GLOBAL(void) jpeg_wxio_dest (j_compress_ptr cinfo, wxOutputStream& outfile)
     dest->stream = &outfile;
 }
 
-bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream )
+bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )
 {
     struct jpeg_compress_struct cinfo;
     struct my_error_mgr jerr;
@@ -274,12 +276,14 @@ bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream )
     cinfo.err = jpeg_std_error(&jerr.pub);
     jerr.pub.error_exit = my_error_exit;
 
+    if (!verbose) cinfo.err->output_message=NULL;
+
     /* Establish the setjmp return context for my_error_exit to use. */
     if (setjmp(jerr.setjmp_buffer)) {
       /* If we get here, the JPEG code has signaled an error.
        * We need to clean up the JPEG object, close the input file, and return.
        */
-      wxLogError(_("Couldn't save a JPEG image - probably file is corrupted."));
+      if (verbose) wxLogError(_("Couldn't save a JPEG image - probably file is corrupted."));
       jpeg_destroy_compress(&cinfo);
       return FALSE;
     }

src/common/imagpng.cpp

@@ -75,7 +75,28 @@ static void LINKAGEMODE _PNG_stream_writer( png_structp png_ptr, png_bytep data,
     ((wxOutputStream*) png_get_io_ptr( png_ptr )) -> Write(data, length);
 }
 
-bool wxPNGHandler::LoadFile( wxImage *image, wxInputStream& stream )
+// from pngerror.c
+// so that the libpng doesn't send anything on stderr
+void
+png_silent_error(png_structp png_ptr, png_const_charp WXUNUSED(message))
+{
+#ifdef USE_FAR_KEYWORD
+   {
+      jmp_buf jmpbuf;
+      png_memcpy(jmpbuf,png_ptr->jmpbuf,sizeof(jmp_buf));
+      longjmp(jmpbuf, 1);
+   }
+#else
+   longjmp(png_ptr->jmpbuf, 1);
+#endif
+}
+
+void
+png_silent_warning(png_structp WXUNUSED(png_ptr), png_const_charp WXUNUSED(message))
+{
+}
+
+bool wxPNGHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose)
 {
     // VZ: as this function uses setjmp() the only fool proof error handling
     //     method is to use goto (setjmp is not really C++ dtors friendly...)
@@ -93,6 +114,9 @@ bool wxPNGHandler::LoadFile( wxImage *image, wxInputStream& stream )
     if (!png_ptr)
         goto error_nolines;
 
+    // the file example.c explain how to guess if the stream is a png image
+    if (!verbose) png_set_error_fn(png_ptr, (png_voidp)NULL, png_silent_error, png_silent_warning);
+
     info_ptr = png_create_info_struct( png_ptr );
     if (!info_ptr)
         goto error_nolines;
@@ -245,7 +269,7 @@ bool wxPNGHandler::LoadFile( wxImage *image, wxInputStream& stream )
 }
 
 
-bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream )
+bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )
 {
     {
         png_structp png_ptr = png_create_write_struct( PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
@@ -254,6 +278,8 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream )
             return FALSE;
         }
 
+	if (!verbose) png_set_error_fn(png_ptr, (png_voidp)NULL, png_silent_error, png_silent_warning);
+
         png_infop info_ptr = png_create_info_struct(png_ptr);
         if (info_ptr == NULL)
         {