Return NULL from wxWindow::GetCapture() when the capture is being lost.

[wxWidgets.git] / src / common / imagbmp.cpp

diff --git a/src/common/imagbmp.cpp b/src/common/imagbmp.cpp
index 6f3a298d18eed65e66b51db3336e4f7512b5565f..c3fcfb275e3719c05c64e2e3ed28de5bd4416ed4 100644 (file)
--- a/src/common/imagbmp.cpp
+++ b/src/common/imagbmp.cpp
@@ -2,7 +2,6 @@
 // Name:        src/common/imagbmp.cpp
 // Purpose:     wxImage BMP,ICO and CUR handlers
 // Author:      Robert Roebling, Chris Elliott
 // Name:        src/common/imagbmp.cpp
 // Purpose:     wxImage BMP,ICO and CUR handlers
 // Author:      Robert Roebling, Chris Elliott

-// RCS-ID:      $Id$

 // Copyright:   (c) Robert Roebling, Chris Elliott
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 // Copyright:   (c) Robert Roebling, Chris Elliott
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////


@@ -39,6 +38,16 @@
 // For memcpy
 #include <string.h>
 
 // For memcpy
 #include <string.h>
 

+// ----------------------------------------------------------------------------
+// private functions
+// ----------------------------------------------------------------------------
+
+#if wxUSE_ICO_CUR
+
+static bool CanReadICOOrCUR(wxInputStream *stream, wxUint16 resourceType);
+
+#endif // wxUSE_ICO_CUR
+

 //-----------------------------------------------------------------------------
 // wxBMPHandler
 //-----------------------------------------------------------------------------
 //-----------------------------------------------------------------------------
 // wxBMPHandler
 //-----------------------------------------------------------------------------


@@ -79,12 +88,14 @@ bool wxBMPHandler::SaveDib(wxImage *image,
                            bool IsMask)
 
 {
                            bool IsMask)
 
 {

-    wxCHECK_MSG( image, false, _T("invalid pointer in wxBMPHandler::SaveFile") );
+    wxCHECK_MSG( image, false, wxT("invalid pointer in wxBMPHandler::SaveFile") );

 
 

-    if ( !image->Ok() )
+    if ( !image->IsOk() )

     {
         if ( verbose )
     {
         if ( verbose )

+        {

             wxLogError(_("BMP: Couldn't save invalid image."));
             wxLogError(_("BMP: Couldn't save invalid image."));

+        }

         return false;
     }
 
         return false;
     }
 


@@ -118,7 +129,9 @@ bool wxBMPHandler::SaveDib(wxImage *image,
             )
         {
             if ( verbose )
             )
         {
             if ( verbose )

+            {

                 wxLogError(_("BMP: wxImage doesn't have own wxPalette."));
                 wxLogError(_("BMP: wxImage doesn't have own wxPalette."));

+            }

             return false;
         }
         bpp = 8;
             return false;
         }
         bpp = 8;


@@ -132,8 +145,8 @@ bool wxBMPHandler::SaveDib(wxImage *image,
     }
 
     unsigned width = image->GetWidth();
     }
 
     unsigned width = image->GetWidth();

-    unsigned row_padding = (4 - int(width*bpp/8.0) % 4) % 4; // # bytes to pad to dword
-    unsigned row_width = int(width * bpp/8.0) + row_padding; // # of bytes per row
+    unsigned row_padding = (4 - ((width * bpp + 7) / 8) % 4) % 4; // # bytes to pad to dword
+    unsigned row_width = (width * bpp + 7) / 8 + row_padding; // # of bytes per row

 
     struct
     {
 
     struct
     {


@@ -184,7 +197,7 @@ bool wxBMPHandler::SaveDib(wxImage *image,
     switch ( GetResolutionFromOptions(*image, &hres, &vres) )
     {
         default:
     switch ( GetResolutionFromOptions(*image, &hres, &vres) )
     {
         default:

-            wxFAIL_MSG( _T("unexpected image resolution units") );
+            wxFAIL_MSG( wxT("unexpected image resolution units") );

             // fall through
 
         case wxIMAGE_RESOLUTION_NONE:
             // fall through
 
         case wxIMAGE_RESOLUTION_NONE:


@@ -215,35 +228,39 @@ bool wxBMPHandler::SaveDib(wxImage *image,
         if (// VS: looks ugly but compilers tend to do ugly things with structs,
             //     like aligning hdr.filesize's ofset to dword :(
             // VZ: we should add padding then...
         if (// VS: looks ugly but compilers tend to do ugly things with structs,
             //     like aligning hdr.filesize's ofset to dword :(
             // VZ: we should add padding then...

-            !stream.Write(&hdr.magic, 2) ||
-            !stream.Write(&hdr.filesize, 4) ||
-            !stream.Write(&hdr.reserved, 4) ||
-            !stream.Write(&hdr.data_offset, 4)
+            !stream.WriteAll(&hdr.magic, 2) ||
+            !stream.WriteAll(&hdr.filesize, 4) ||
+            !stream.WriteAll(&hdr.reserved, 4) ||
+            !stream.WriteAll(&hdr.data_offset, 4)

            )
         {
             if (verbose)
            )
         {
             if (verbose)

+            {

                 wxLogError(_("BMP: Couldn't write the file (Bitmap) header."));
                 wxLogError(_("BMP: Couldn't write the file (Bitmap) header."));

+                }

             return false;
         }
     }
     if ( !IsMask )
     {
         if (
             return false;
         }
     }
     if ( !IsMask )
     {
         if (

-            !stream.Write(&hdr.bih_size, 4) ||
-            !stream.Write(&hdr.width, 4) ||
-            !stream.Write(&hdr.height, 4) ||
-            !stream.Write(&hdr.planes, 2) ||
-            !stream.Write(&hdr.bpp, 2) ||
-            !stream.Write(&hdr.compression, 4) ||
-            !stream.Write(&hdr.size_of_bmp, 4) ||
-            !stream.Write(&hdr.h_res, 4) ||
-            !stream.Write(&hdr.v_res, 4) ||
-            !stream.Write(&hdr.num_clrs, 4) ||
-            !stream.Write(&hdr.num_signif_clrs, 4)
+            !stream.WriteAll(&hdr.bih_size, 4) ||
+            !stream.WriteAll(&hdr.width, 4) ||
+            !stream.WriteAll(&hdr.height, 4) ||
+            !stream.WriteAll(&hdr.planes, 2) ||
+            !stream.WriteAll(&hdr.bpp, 2) ||
+            !stream.WriteAll(&hdr.compression, 4) ||
+            !stream.WriteAll(&hdr.size_of_bmp, 4) ||
+            !stream.WriteAll(&hdr.h_res, 4) ||
+            !stream.WriteAll(&hdr.v_res, 4) ||
+            !stream.WriteAll(&hdr.num_clrs, 4) ||
+            !stream.WriteAll(&hdr.num_signif_clrs, 4)

            )
         {
             if (verbose)
            )
         {
             if (verbose)

+            {

                 wxLogError(_("BMP: Couldn't write the file (BitmapInfo) header."));
                 wxLogError(_("BMP: Couldn't write the file (BitmapInfo) header."));

+            }

             return false;
         }
     }
             return false;
         }
     }


@@ -314,10 +331,12 @@ bool wxBMPHandler::SaveDib(wxImage *image,
     {
         if ( !IsMask )
         {
     {
         if ( !IsMask )
         {

-            if ( !stream.Write(rgbquad, palette_size*4) )
+            if ( !stream.WriteAll(rgbquad, palette_size*4) )

             {
                 if (verbose)
             {
                 if (verbose)

+                {

                     wxLogError(_("BMP: Couldn't write RGB color map."));
                     wxLogError(_("BMP: Couldn't write RGB color map."));

+                }

                 delete[] rgbquad;
 #if wxUSE_PALETTE
                 delete palette;
                 delete[] rgbquad;
 #if wxUSE_PALETTE
                 delete palette;


@@ -331,7 +350,7 @@ bool wxBMPHandler::SaveDib(wxImage *image,
 
     // pointer to the image data, use quantized if available
     wxUint8 *data = (wxUint8*) image->GetData();
 
     // pointer to the image data, use quantized if available
     wxUint8 *data = (wxUint8*) image->GetData();

-    if (q_image) if (q_image->Ok()) data = (wxUint8*) q_image->GetData();
+    if (q_image) if (q_image->IsOk()) data = (wxUint8*) q_image->GetData();

 
     wxUint8 *buffer = new wxUint8[row_width];
     memset(buffer, 0, row_width);
 
     wxUint8 *buffer = new wxUint8[row_width];
     memset(buffer, 0, row_width);


@@ -447,10 +466,12 @@ bool wxBMPHandler::SaveDib(wxImage *image,
             }
         }
 
             }
         }
 

-        if ( !stream.Write(buffer, row_width) )
+        if ( !stream.WriteAll(buffer, row_width) )

         {
             if (verbose)
         {
             if (verbose)

+            {

                 wxLogError(_("BMP: Couldn't write data."));
                 wxLogError(_("BMP: Couldn't write data."));

+            }

             delete[] buffer;
 #if wxUSE_PALETTE
             delete palette;
             delete[] buffer;
 #if wxUSE_PALETTE
             delete palette;


@@ -498,7 +519,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
         if ( !cmap )
         {
             if (verbose)
         if ( !cmap )
         {
             if (verbose)

+            {

                 wxLogError(_("BMP: Couldn't allocate memory."));
                 wxLogError(_("BMP: Couldn't allocate memory."));

+            }

             return false;
         }
     }
             return false;
         }
     }


@@ -509,6 +532,14 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
 
     wxON_BLOCK_EXIT1(&BMPPalette::Free, cmap);
 
 
     wxON_BLOCK_EXIT1(&BMPPalette::Free, cmap);
 

+    bool isUpsideDown = true;
+
+    if (height < 0)
+    {
+        isUpsideDown = false;
+        height = -height;
+    }
+

     // destroy existing here instead of:
     image->Destroy();
     image->Create(width, height);
     // destroy existing here instead of:
     image->Destroy();
     image->Create(width, height);


@@ -518,7 +549,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
     if ( !ptr )
     {
         if ( verbose )
     if ( !ptr )
     {
         if ( verbose )

+        {

             wxLogError( _("BMP: Couldn't allocate memory.") );
             wxLogError( _("BMP: Couldn't allocate memory.") );

+        }

         return false;
     }
 
         return false;
     }
 


@@ -531,7 +564,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
         if ( !alpha )
         {
             if ( verbose )
         if ( !alpha )
         {
             if ( verbose )

+            {

                 wxLogError(_("BMP: Couldn't allocate memory."));
                 wxLogError(_("BMP: Couldn't allocate memory."));

+            }

             return false;
         }
     }
             return false;
         }
     }


@@ -550,7 +585,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
         {
             if (hasPalette)
             {
         {
             if (hasPalette)
             {

-                stream.Read(bbuf, 4);
+                if ( !stream.ReadAll(bbuf, 4) )
+                    return false;
+

                 cmap[j].b = bbuf[0];
                 cmap[j].g = bbuf[1];
                 cmap[j].r = bbuf[2];
                 cmap[j].b = bbuf[0];
                 cmap[j].g = bbuf[1];
                 cmap[j].r = bbuf[2];


@@ -581,8 +618,10 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
     {
         if ( comp == BI_BITFIELDS )
         {
     {
         if ( comp == BI_BITFIELDS )
         {

-            int bit = 0;
-            stream.Read(dbuf, 4 * 3);
+            int bit;
+            if ( !stream.ReadAll(dbuf, 4 * 3) )
+                return false;
+

             rmask = wxINT32_SWAP_ON_BE(dbuf[0]);
             gmask = wxINT32_SWAP_ON_BE(dbuf[1]);
             bmask = wxINT32_SWAP_ON_BE(dbuf[2]);
             rmask = wxINT32_SWAP_ON_BE(dbuf[0]);
             gmask = wxINT32_SWAP_ON_BE(dbuf[1]);
             bmask = wxINT32_SWAP_ON_BE(dbuf[2]);


@@ -641,7 +680,12 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
      */
     if ( IsBmp )
     {
      */
     if ( IsBmp )
     {

-        if (stream.SeekI(bmpOffset) == wxInvalidOffset)
+        // NOTE: seeking a positive amount in wxFromCurrent mode allows us to
+        //       load even non-seekable streams (see wxInputStream::SeekI docs)!
+        const wxFileOffset pos = stream.TellI();
+        if ( pos == wxInvalidOffset ||
+             (bmpOffset > pos &&
+              stream.SeekI(bmpOffset - pos, wxFromCurrent) == wxInvalidOffset) )

             return false;
         //else: icon, just carry on
     }
             return false;
         //else: icon, just carry on
     }


@@ -662,9 +706,18 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
 
     int linesize = ((width * bpp + 31) / 32) * 4;
 
 
     int linesize = ((width * bpp + 31) / 32) * 4;
 

-    /* BMPs are stored upside down */
-    for ( int line = (height - 1); line >= 0; line-- )
+    // flag indicating if we have any not fully transparent alpha values: this
+    // is used to account for the bitmaps which use 32bpp format (normally
+    // meaning that they have alpha channel) but have only zeroes in it so that
+    // without this hack they appear fully transparent -- and as this is
+    // unlikely intentional, we consider that they don't have alpha at all in
+    // this case (see #10915)
+    bool hasValidAlpha = false;
+
+    for ( int row = 0; row < height; row++ )

     {
     {

+        int line = isUpsideDown ? height - 1 - row : row;
+

         int linepos = 0;
         for ( int column = 0; column < width ; )
         {
         int linepos = 0;
         for ( int column = 0; column < width ; )
         {


@@ -672,6 +725,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             {
                 linepos++;
                 aByte = stream.GetC();
             {
                 linepos++;
                 aByte = stream.GetC();

+                if ( !stream.IsOk() )
+                    return false;
+

                 if ( bpp == 1 )
                 {
                     for (int bit = 0; bit < 8 && column < width; bit++)
                 if ( bpp == 1 )
                 {
                     for (int bit = 0; bit < 8 && column < width; bit++)


@@ -690,25 +746,35 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                         wxUint8 first;
                         first = aByte;
                         aByte = stream.GetC();
                         wxUint8 first;
                         first = aByte;
                         aByte = stream.GetC();

+                        if ( !stream.IsOk() )
+                            return false;
+

                         if ( first == 0 )
                         {
                             if ( aByte == 0 )
                             {
                         if ( first == 0 )
                         {
                             if ( aByte == 0 )
                             {

-                                if ( column > 0 )
-                                    column = width;
+                                // end of scanline marker
+                                column = width;
+                                row--;

                             }
                             else if ( aByte == 1 )
                             {
                             }
                             else if ( aByte == 1 )
                             {

+                                // end of RLE data marker, stop decoding

                                 column = width;
                                 column = width;

-                                line = -1;
+                                row = height;

                             }
                             else if ( aByte == 2 )
                             {
                             }
                             else if ( aByte == 2 )
                             {

+                                // delta marker, move in image

                                 aByte = stream.GetC();
                                 aByte = stream.GetC();

+                                if ( !stream.IsOk() )
+                                    return false;

                                 column += aByte;
                                 linepos = column * bpp / 4;
                                 aByte = stream.GetC();
                                 column += aByte;
                                 linepos = column * bpp / 4;
                                 aByte = stream.GetC();

-                                line -= aByte; // upside down
+                                if ( !stream.IsOk() )
+                                    return false;
+                                row += aByte; // upside down

                             }
                             else
                             {
                             }
                             else
                             {


@@ -721,6 +787,8 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                                     {
                                         ++readBytes ;
                                         aByte = stream.GetC();
                                     {
                                         ++readBytes ;
                                         aByte = stream.GetC();

+                                        if ( !stream.IsOk() )
+                                            return false;

                                         nibble[0] = (wxUint8)( (aByte & 0xF0) >> 4 ) ;
                                         nibble[1] = (wxUint8)( aByte & 0x0F ) ;
                                     }
                                         nibble[0] = (wxUint8)( (aByte & 0xF0) >> 4 ) ;
                                         nibble[1] = (wxUint8)( aByte & 0x0F ) ;
                                     }


@@ -732,7 +800,11 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                                         linepos++;
                                 }
                                 if ( readBytes & 0x01 )
                                         linepos++;
                                 }
                                 if ( readBytes & 0x01 )

+                                {

                                     aByte = stream.GetC();
                                     aByte = stream.GetC();

+                                    if ( !stream.IsOk() )
+                                        return false;
+                                }

                             }
                         }
                         else
                             }
                         }
                         else


@@ -756,7 +828,7 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                     {
                         for (int nibble = 0; nibble < 2 && column < width; nibble++)
                         {
                     {
                         for (int nibble = 0; nibble < 2 && column < width; nibble++)
                         {

-                            int index = ((aByte & (0xF0 >> nibble * 4)) >> (!nibble * 4));
+                            int index = ((aByte & (0xF0 >> (nibble * 4))) >> (!nibble * 4));

                             if ( index >= 16 )
                                 index = 15;
                             ptr[poffset] = cmap[index].r;
                             if ( index >= 16 )
                                 index = 15;
                             ptr[poffset] = cmap[index].r;


@@ -773,24 +845,35 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                         unsigned char first;
                         first = aByte;
                         aByte = stream.GetC();
                         unsigned char first;
                         first = aByte;
                         aByte = stream.GetC();

+                        if ( !stream.IsOk() )
+                            return false;
+

                         if ( first == 0 )
                         {
                             if ( aByte == 0 )
                             {
                         if ( first == 0 )
                         {
                             if ( aByte == 0 )
                             {

-                                /* column = width; */
+                                // end of scanline marker
+                                column = width;
+                                row--;

                             }
                             else if ( aByte == 1 )
                             {
                             }
                             else if ( aByte == 1 )
                             {

+                                // end of RLE data marker, stop decoding

                                 column = width;
                                 column = width;

-                                line = -1;
+                                row = height;

                             }
                             else if ( aByte == 2 )
                             {
                             }
                             else if ( aByte == 2 )
                             {

+                                // delta marker, move in image

                                 aByte = stream.GetC();
                                 aByte = stream.GetC();

+                                if ( !stream.IsOk() )
+                                    return false;

                                 column += aByte;
                                 linepos = column * bpp / 8;
                                 aByte = stream.GetC();
                                 column += aByte;
                                 linepos = column * bpp / 8;
                                 aByte = stream.GetC();

-                                line += aByte;
+                                if ( !stream.IsOk() )
+                                    return false;
+                                row -= aByte;

                             }
                             else
                             {
                             }
                             else
                             {


@@ -799,13 +882,19 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                                 {
                                     linepos++;
                                     aByte = stream.GetC();
                                 {
                                     linepos++;
                                     aByte = stream.GetC();

+                                    if ( !stream.IsOk() )
+                                        return false;

                                     ptr[poffset    ] = cmap[aByte].r;
                                     ptr[poffset + 1] = cmap[aByte].g;
                                     ptr[poffset + 2] = cmap[aByte].b;
                                     column++;
                                 }
                                 if ( absolute & 0x01 )
                                     ptr[poffset    ] = cmap[aByte].r;
                                     ptr[poffset + 1] = cmap[aByte].g;
                                     ptr[poffset + 2] = cmap[aByte].b;
                                     column++;
                                 }
                                 if ( absolute & 0x01 )

+                                {

                                     aByte = stream.GetC();
                                     aByte = stream.GetC();

+                                    if ( !stream.IsOk() )
+                                        return false;
+                                }

                             }
                         }
                         else
                             }
                         }
                         else


@@ -832,7 +921,8 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             }
             else if ( bpp == 24 )
             {
             }
             else if ( bpp == 24 )
             {

-                stream.Read(bbuf, 3);
+                if ( !stream.ReadAll(bbuf, 3) )
+                    return false;

                 linepos += 3;
                 ptr[poffset    ] = (unsigned char)bbuf[2];
                 ptr[poffset + 1] = (unsigned char)bbuf[1];
                 linepos += 3;
                 ptr[poffset    ] = (unsigned char)bbuf[2];
                 ptr[poffset + 1] = (unsigned char)bbuf[1];


@@ -842,25 +932,28 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             else if ( bpp == 16 )
             {
                 unsigned char temp;
             else if ( bpp == 16 )
             {
                 unsigned char temp;

-                stream.Read(&aWord, 2);
+                if ( !stream.ReadAll(&aWord, 2) )
+                    return false;

                 aWord = wxUINT16_SWAP_ON_BE(aWord);
                 linepos += 2;
                 aWord = wxUINT16_SWAP_ON_BE(aWord);
                 linepos += 2;

-                /* use the masks and calculated amonut of shift
+                /* Use the masks and calculated amount of shift

                    to retrieve the color data out of the word.  Then
                    shift it left by (8 - number of bits) such that
                    the image has the proper dynamic range */
                    to retrieve the color data out of the word.  Then
                    shift it left by (8 - number of bits) such that
                    the image has the proper dynamic range */

-                temp = (unsigned char)((aWord & rmask) >> rshift << (8-rbits));
+                temp = (unsigned char)(((aWord & rmask) >> rshift) << (8-rbits));

                 ptr[poffset] = temp;
                 ptr[poffset] = temp;

-                temp = (unsigned char)((aWord & gmask) >> gshift << (8-gbits));
+                temp = (unsigned char)(((aWord & gmask) >> gshift) << (8-gbits));

                 ptr[poffset + 1] = temp;
                 ptr[poffset + 1] = temp;

-                temp = (unsigned char)((aWord & bmask) >> bshift << (8-bbits));
+                temp = (unsigned char)(((aWord & bmask) >> bshift) << (8-bbits));

                 ptr[poffset + 2] = temp;
                 column++;
             }
             else
             {
                 unsigned char temp;
                 ptr[poffset + 2] = temp;
                 column++;
             }
             else
             {
                 unsigned char temp;

-                stream.Read(&aDword, 4);
+                if ( !stream.ReadAll(&aDword, 4) )
+                    return false;
+

                 aDword = wxINT32_SWAP_ON_BE(aDword);
                 linepos += 4;
                 temp = (unsigned char)((aDword & rmask) >> rshift);
                 aDword = wxINT32_SWAP_ON_BE(aDword);
                 linepos += 4;
                 temp = (unsigned char)((aDword & rmask) >> rshift);


@@ -873,21 +966,30 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                 {
                     temp = (unsigned char)((aDword & amask) >> ashift);
                     alpha[line * width + column] = temp;
                 {
                     temp = (unsigned char)((aDword & amask) >> ashift);
                     alpha[line * width + column] = temp;

+
+                    if ( temp != wxALPHA_TRANSPARENT )
+                        hasValidAlpha = true;

                 }
                 column++;
             }
         }
         while ( (linepos < linesize) && (comp != 1) && (comp != 2) )
         {
                 }
                 column++;
             }
         }
         while ( (linepos < linesize) && (comp != 1) && (comp != 2) )
         {

-            stream.Read(&aByte, 1);
-            linepos += 1;
-            if ( !stream )
+            ++linepos;
+            if ( !stream.ReadAll(&aByte, 1) )

                 break;
         }
     }
 
     image->SetMask(false);
 
                 break;
         }
     }
 
     image->SetMask(false);
 

+    // check if we had any valid alpha values in this bitmap
+    if ( alpha && !hasValidAlpha )
+    {
+        // we didn't, so finally discard the alpha channel completely
+        image->ClearAlpha();
+    }
+

     const wxStreamError err = stream.GetLastError();
     return err == wxSTREAM_NO_ERROR || err == wxSTREAM_EOF;
 }
     const wxStreamError err = stream.GetLastError();
     return err == wxSTREAM_NO_ERROR || err == wxSTREAM_EOF;
 }


@@ -899,28 +1001,26 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
     wxInt32         dbuf[4];
     wxInt8          bbuf[4];
 
     wxInt32         dbuf[4];
     wxInt8          bbuf[4];
 

-    wxFileOffset offset = 0; // keep gcc quiet

     if ( IsBmp )
     {
         // read the header off the .BMP format file
     if ( IsBmp )
     {
         // read the header off the .BMP format file

-
-        offset = stream.TellI();
-        if (offset == wxInvalidOffset)
-            offset = 0;
-
-        stream.Read(bbuf, 2);
-        stream.Read(dbuf, 16);
+        if ( !stream.ReadAll(bbuf, 2) ||
+             !stream.ReadAll(dbuf, 16) )
+            return false;

     }
     else
     {
     }
     else
     {

-        stream.Read(dbuf, 4);
+        if ( !stream.ReadAll(dbuf, 4) )
+            return false;

     }
     #if 0 // unused
         wxInt32 size = wxINT32_SWAP_ON_BE(dbuf[0]);
     #endif
     }
     #if 0 // unused
         wxInt32 size = wxINT32_SWAP_ON_BE(dbuf[0]);
     #endif

-    offset = offset + wxINT32_SWAP_ON_BE(dbuf[2]);
+    wxFileOffset offset = wxINT32_SWAP_ON_BE(dbuf[2]);
+
+    if ( !stream.ReadAll(dbuf, 4 * 2) )
+        return false;

 
 

-    stream.Read(dbuf, 4 * 2);

     int width = wxINT32_SWAP_ON_BE((int)dbuf[0]);
     int height = wxINT32_SWAP_ON_BE((int)dbuf[1]);
     if ( !IsBmp)height = height  / 2; // for icons divide by 2
     int width = wxINT32_SWAP_ON_BE((int)dbuf[0]);
     int height = wxINT32_SWAP_ON_BE((int)dbuf[1]);
     if ( !IsBmp)height = height  / 2; // for icons divide by 2


@@ -928,41 +1028,56 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
     if ( width > 32767 )
     {
         if (verbose)
     if ( width > 32767 )
     {
         if (verbose)

+        {

             wxLogError( _("DIB Header: Image width > 32767 pixels for file.") );
             wxLogError( _("DIB Header: Image width > 32767 pixels for file.") );

+        }

         return false;
     }
     if ( height > 32767 )
     {
         if (verbose)
         return false;
     }
     if ( height > 32767 )
     {
         if (verbose)

+        {

             wxLogError( _("DIB Header: Image height > 32767 pixels for file.") );
             wxLogError( _("DIB Header: Image height > 32767 pixels for file.") );

+        }

         return false;
     }
 
         return false;
     }
 

-    stream.Read(&aWord, 2);
+    if ( !stream.ReadAll(&aWord, 2) )
+        return false;
+

     /*
             TODO
             int planes = (int)wxUINT16_SWAP_ON_BE( aWord );
         */
     /*
             TODO
             int planes = (int)wxUINT16_SWAP_ON_BE( aWord );
         */

-    stream.Read(&aWord, 2);
+    if ( !stream.ReadAll(&aWord, 2) )
+        return false;
+

     int bpp = wxUINT16_SWAP_ON_BE((int)aWord);
     if ( bpp != 1 && bpp != 4 && bpp != 8 && bpp != 16 && bpp != 24 && bpp != 32 )
     {
         if (verbose)
     int bpp = wxUINT16_SWAP_ON_BE((int)aWord);
     if ( bpp != 1 && bpp != 4 && bpp != 8 && bpp != 16 && bpp != 24 && bpp != 32 )
     {
         if (verbose)

+        {

             wxLogError( _("DIB Header: Unknown bitdepth in file.") );
             wxLogError( _("DIB Header: Unknown bitdepth in file.") );

+        }

         return false;
     }
 
         return false;
     }
 

-    stream.Read(dbuf, 4 * 4);
+    if ( !stream.ReadAll(dbuf, 4 * 4) )
+        return false;
+

     int comp = wxINT32_SWAP_ON_BE((int)dbuf[0]);
     if ( comp != BI_RGB && comp != BI_RLE4 && comp != BI_RLE8 &&
          comp != BI_BITFIELDS )
     {
         if (verbose)
     int comp = wxINT32_SWAP_ON_BE((int)dbuf[0]);
     if ( comp != BI_RGB && comp != BI_RLE4 && comp != BI_RLE8 &&
          comp != BI_BITFIELDS )
     {
         if (verbose)

+        {

             wxLogError( _("DIB Header: Unknown encoding in file.") );
             wxLogError( _("DIB Header: Unknown encoding in file.") );

+        }

         return false;
     }
 
         return false;
     }
 

-    stream.Read(dbuf, 4 * 2);
+    if ( !stream.ReadAll(dbuf, 4 * 2) )
+        return false;

 
     int ncolors = wxINT32_SWAP_ON_BE( (int)dbuf[0] );
     if (ncolors == 0)
 
     int ncolors = wxINT32_SWAP_ON_BE( (int)dbuf[0] );
     if (ncolors == 0)


@@ -973,7 +1088,9 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
         ((comp == BI_BITFIELDS) && (bpp != 16 && bpp != 32)))
     {
         if (verbose)
         ((comp == BI_BITFIELDS) && (bpp != 16 && bpp != 32)))
     {
         if (verbose)

+        {

             wxLogError( _("DIB Header: Encoding doesn't match bitdepth.") );
             wxLogError( _("DIB Header: Encoding doesn't match bitdepth.") );

+        }

         return false;
     }
 
         return false;
     }
 


@@ -982,7 +1099,9 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
                     verbose, IsBmp, true) )
     {
         if (verbose)
                     verbose, IsBmp, true) )
     {
         if (verbose)

+        {

             wxLogError( _("Error in reading image DIB.") );
             wxLogError( _("Error in reading image DIB.") );

+        }

         return false;
     }
 
         return false;
     }
 


@@ -995,7 +1114,9 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
                         verbose, IsBmp, false) )
         {
             if (verbose)
                         verbose, IsBmp, false) )
         {
             if (verbose)

+            {

                 wxLogError( _("ICO: Error in reading mask DIB.") );
                 wxLogError( _("ICO: Error in reading mask DIB.") );

+            }

             return false;
         }
         image->SetMaskFromImage(mask, 255, 255, 255);
             return false;
         }
         image->SetMaskFromImage(mask, 255, 255, 255);


@@ -1021,7 +1142,7 @@ bool wxBMPHandler::DoCanRead(wxInputStream& stream)
 {
     unsigned char hdr[2];
 
 {
     unsigned char hdr[2];
 

-    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
+    if ( !stream.ReadAll(hdr, WXSIZEOF(hdr)) )     // it's ok to modify the stream position here

         return false;
 
     // do we have the BMP file signature?
         return false;
 
     // do we have the BMP file signature?


@@ -1073,13 +1194,17 @@ bool wxICOHandler::SaveFile(wxImage *image,
     if ( image->GetHeight () > 127 )
     {
         if ( verbose )
     if ( image->GetHeight () > 127 )
     {
         if ( verbose )

+        {

             wxLogError(_("ICO: Image too tall for an icon."));
             wxLogError(_("ICO: Image too tall for an icon."));

+        }

         return false;
     }
     if ( image->GetWidth () > 255 )
     {
         if ( verbose )
         return false;
     }
     if ( image->GetWidth () > 255 )
     {
         if ( verbose )

+        {

             wxLogError(_("ICO: Image too wide for an icon."));
             wxLogError(_("ICO: Image too wide for an icon."));

+        }

         return false;
     }
 
         return false;
     }
 


@@ -1099,13 +1224,14 @@ bool wxICOHandler::SaveFile(wxImage *image,
     IconDir.idReserved = 0;
     IconDir.idType = wxUINT16_SWAP_ON_BE((wxUint16)type);
     IconDir.idCount = wxUINT16_SWAP_ON_BE((wxUint16)images);
     IconDir.idReserved = 0;
     IconDir.idType = wxUINT16_SWAP_ON_BE((wxUint16)type);
     IconDir.idCount = wxUINT16_SWAP_ON_BE((wxUint16)images);

-    stream.Write(&IconDir.idReserved, sizeof(IconDir.idReserved));
-    stream.Write(&IconDir.idType, sizeof(IconDir.idType));
-    stream.Write(&IconDir.idCount, sizeof(IconDir.idCount));
-    if ( !stream.IsOk() )
+    if ( !stream.WriteAll(&IconDir.idReserved, sizeof(IconDir.idReserved)) ||
+         !stream.WriteAll(&IconDir.idType, sizeof(IconDir.idType)) ||
+         !stream.WriteAll(&IconDir.idCount, sizeof(IconDir.idCount)) )

     {
         if ( verbose )
     {
         if ( verbose )

+        {

             wxLogError(_("ICO: Error writing the image file!"));
             wxLogError(_("ICO: Error writing the image file!"));

+        }

         return false;
     }
 
         return false;
     }
 


@@ -1164,7 +1290,9 @@ bool wxICOHandler::SaveFile(wxImage *image,
         if ( !bResult )
         {
             if ( verbose )
         if ( !bResult )
         {
             if ( verbose )

+            {

                 wxLogError(_("ICO: Error writing the image file!"));
                 wxLogError(_("ICO: Error writing the image file!"));

+            }

             return false;
         }
         IsMask = true;
             return false;
         }
         IsMask = true;


@@ -1173,7 +1301,9 @@ bool wxICOHandler::SaveFile(wxImage *image,
         if ( !bResult )
         {
             if ( verbose )
         if ( !bResult )
         {
             if ( verbose )

+            {

                 wxLogError(_("ICO: Error writing the image file!"));
                 wxLogError(_("ICO: Error writing the image file!"));

+            }

             return false;
         }
         wxUint32 Size = cStream.GetSize();
             return false;
         }
         wxUint32 Size = cStream.GetSize();


@@ -1181,10 +1311,12 @@ bool wxICOHandler::SaveFile(wxImage *image,
         // wxCountingOutputStream::IsOk() always returns true for now and this
         // "if" provokes VC++ warnings in optimized build
 #if 0
         // wxCountingOutputStream::IsOk() always returns true for now and this
         // "if" provokes VC++ warnings in optimized build
 #if 0

-        if ( !cStream.Ok() )
+        if ( !cStream.IsOk() )

         {
             if ( verbose )
         {
             if ( verbose )

+            {

                 wxLogError(_("ICO: Error writing the image file!"));
                 wxLogError(_("ICO: Error writing the image file!"));

+            }

             return false;
         }
 #endif // 0
             return false;
         }
 #endif // 0


@@ -1217,18 +1349,19 @@ bool wxICOHandler::SaveFile(wxImage *image,
         offset += Size;
 
         // write to stream:
         offset += Size;
 
         // write to stream:

-        stream.Write(&icondirentry.bWidth, sizeof(icondirentry.bWidth));
-        stream.Write(&icondirentry.bHeight, sizeof(icondirentry.bHeight));
-        stream.Write(&icondirentry.bColorCount, sizeof(icondirentry.bColorCount));
-        stream.Write(&icondirentry.bReserved, sizeof(icondirentry.bReserved));
-        stream.Write(&icondirentry.wPlanes, sizeof(icondirentry.wPlanes));
-        stream.Write(&icondirentry.wBitCount, sizeof(icondirentry.wBitCount));
-        stream.Write(&icondirentry.dwBytesInRes, sizeof(icondirentry.dwBytesInRes));
-        stream.Write(&icondirentry.dwImageOffset, sizeof(icondirentry.dwImageOffset));
-        if ( !stream.IsOk() )
+        if ( !stream.WriteAll(&icondirentry.bWidth, sizeof(icondirentry.bWidth)) ||
+             !stream.WriteAll(&icondirentry.bHeight, sizeof(icondirentry.bHeight)) ||
+             !stream.WriteAll(&icondirentry.bColorCount, sizeof(icondirentry.bColorCount)) ||
+             !stream.WriteAll(&icondirentry.bReserved, sizeof(icondirentry.bReserved)) ||
+             !stream.WriteAll(&icondirentry.wPlanes, sizeof(icondirentry.wPlanes)) ||
+             !stream.WriteAll(&icondirentry.wBitCount, sizeof(icondirentry.wBitCount)) ||
+             !stream.WriteAll(&icondirentry.dwBytesInRes, sizeof(icondirentry.dwBytesInRes)) ||
+             !stream.WriteAll(&icondirentry.dwImageOffset, sizeof(icondirentry.dwImageOffset)) )

         {
             if ( verbose )
         {
             if ( verbose )

+            {

                 wxLogError(_("ICO: Error writing the image file!"));
                 wxLogError(_("ICO: Error writing the image file!"));

+            }

             return false;
         }
 
             return false;
         }
 


@@ -1238,7 +1371,9 @@ bool wxICOHandler::SaveFile(wxImage *image,
         if ( !bResult )
         {
             if ( verbose )
         if ( !bResult )
         {
             if ( verbose )

+            {

                 wxLogError(_("ICO: Error writing the image file!"));
                 wxLogError(_("ICO: Error writing the image file!"));

+            }

             return false;
         }
         IsMask = true;
             return false;
         }
         IsMask = true;


@@ -1247,7 +1382,9 @@ bool wxICOHandler::SaveFile(wxImage *image,
         if ( !bResult )
         {
             if ( verbose )
         if ( !bResult )
         {
             if ( verbose )

+            {

                 wxLogError(_("ICO: Error writing the image file!"));
                 wxLogError(_("ICO: Error writing the image file!"));

+            }

             return false;
         }
 
             return false;
         }
 


@@ -1259,8 +1396,11 @@ bool wxICOHandler::SaveFile(wxImage *image,
 bool wxICOHandler::LoadFile(wxImage *image, wxInputStream& stream,
                             bool verbose, int index)
 {
 bool wxICOHandler::LoadFile(wxImage *image, wxInputStream& stream,
                             bool verbose, int index)
 {

-    if (stream.SeekI(0) == wxInvalidOffset)
+    if ( stream.IsSeekable() && stream.SeekI(0) == wxInvalidOffset )
+    {

         return false;
         return false;

+    }
+

     return DoLoadFile(image, stream, verbose, index);
 }
 
     return DoLoadFile(image, stream, verbose, index);
 }
 


@@ -1272,9 +1412,11 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
 
     ICONDIR IconDir;
 
 
     ICONDIR IconDir;
 

-    wxFileOffset iPos = stream.TellI();
-    stream.Read(&IconDir, sizeof(IconDir));
+    if ( !stream.ReadAll(&IconDir, sizeof(IconDir)) )
+        return false;
+

     wxUint16 nIcons = wxUINT16_SWAP_ON_BE(IconDir.idCount);
     wxUint16 nIcons = wxUINT16_SWAP_ON_BE(IconDir.idCount);

+

     // nType is 1 for Icons, 2 for Cursors:
     wxUint16 nType = wxUINT16_SWAP_ON_BE(IconDir.idType);
 
     // nType is 1 for Icons, 2 for Cursors:
     wxUint16 nType = wxUINT16_SWAP_ON_BE(IconDir.idType);
 


@@ -1285,9 +1427,16 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
     int colmax = 0;
     int iSel = wxNOT_FOUND;
 
     int colmax = 0;
     int iSel = wxNOT_FOUND;
 

-    for (int i = 0; i < nIcons; i++ )
+    // remember how many bytes we read from the stream:
+    wxFileOffset alreadySeeked = sizeof(IconDir);
+
+    for (unsigned int i = 0; i < nIcons; i++ )

     {
     {

-        stream.Read(pCurrentEntry, sizeof(ICONDIRENTRY));
+        if ( !stream.ReadAll(pCurrentEntry, sizeof(ICONDIRENTRY)) )
+            return false;
+
+        alreadySeeked += stream.LastRead();
+

         // bHeight and bColorCount are wxUint8
         if ( pCurrentEntry->bWidth >= wMax )
         {
         // bHeight and bColorCount are wxUint8
         if ( pCurrentEntry->bWidth >= wMax )
         {


@@ -1301,6 +1450,7 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
                 colmax = pCurrentEntry->bColorCount;
             }
         }
                 colmax = pCurrentEntry->bColorCount;
             }
         }

+

         pCurrentEntry++;
     }
 
         pCurrentEntry++;
     }
 


@@ -1320,8 +1470,13 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
     {
         // seek to selected icon:
         pCurrentEntry = pIconDirEntry + iSel;
     {
         // seek to selected icon:
         pCurrentEntry = pIconDirEntry + iSel;

-        if (stream.SeekI(iPos + wxUINT32_SWAP_ON_BE(pCurrentEntry->dwImageOffset), wxFromStart) == wxInvalidOffset)
+
+        // NOTE: seeking a positive amount in wxFromCurrent mode allows us to
+        //       load even non-seekable streams (see wxInputStream::SeekI docs)!
+        wxFileOffset offset = wxUINT32_SWAP_ON_BE(pCurrentEntry->dwImageOffset) - alreadySeeked;
+        if (offset != 0 && stream.SeekI(offset, wxFromCurrent) == wxInvalidOffset)

             return false;
             return false;

+

         bResult = LoadDib(image, stream, true, IsBmp);
         bool bIsCursorType = (this->GetType() == wxBITMAP_TYPE_CUR) || (this->GetType() == wxBITMAP_TYPE_ANI);
         if ( bResult && bIsCursorType && nType == 2 )
         bResult = LoadDib(image, stream, true, IsBmp);
         bool bIsCursorType = (this->GetType() == wxBITMAP_TYPE_CUR) || (this->GetType() == wxBITMAP_TYPE_ANI);
         if ( bResult && bIsCursorType && nType == 2 )


@@ -1331,34 +1486,33 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
             image->SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, wxUINT16_SWAP_ON_BE(pCurrentEntry->wBitCount));
         }
     }
             image->SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, wxUINT16_SWAP_ON_BE(pCurrentEntry->wBitCount));
         }
     }

-    delete[] pIconDirEntry;
+
+    delete [] pIconDirEntry;
+

     return bResult;
 }
 
     return bResult;
 }
 

-int wxICOHandler::GetImageCount(wxInputStream& stream)
+int wxICOHandler::DoGetImageCount(wxInputStream& stream)

 {
 {

-    ICONDIR IconDir;
-    wxFileOffset iPos = stream.TellI();
-    if (stream.SeekI(0) == wxInvalidOffset)
-        return 0;
-    if (stream.Read(&IconDir, sizeof(IconDir)).LastRead() != sizeof(IconDir))
+    // It's ok to modify the stream position in this function.
+
+    if ( stream.IsSeekable() && stream.SeekI(0) == wxInvalidOffset )
+    {

         return 0;
         return 0;

-    wxUint16 nIcons = wxUINT16_SWAP_ON_BE(IconDir.idCount);
-    if (stream.SeekI(iPos) == wxInvalidOffset)
+    }
+
+    ICONDIR IconDir;
+
+    if ( !stream.ReadAll(&IconDir, sizeof(IconDir)) )

         return 0;
         return 0;

-    return (int)nIcons;
+
+    return (int)wxUINT16_SWAP_ON_BE(IconDir.idCount);

 }
 
 bool wxICOHandler::DoCanRead(wxInputStream& stream)
 {
 }
 
 bool wxICOHandler::DoCanRead(wxInputStream& stream)
 {

-    if (stream.SeekI(0) == wxInvalidOffset)
-        return false;
-    unsigned char hdr[4];
-    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
-        return false;
+    return CanReadICOOrCUR(&stream, 1 /*for identifying an icon*/);

 
 

-    // hdr[2] is one for an icon and two for a cursor
-    return hdr[0] == '\0' && hdr[1] == '\0' && hdr[2] == '\1' && hdr[3] == '\0';

 }
 
 #endif // wxUSE_STREAMS
 }
 
 #endif // wxUSE_STREAMS


@@ -1374,14 +1528,7 @@ IMPLEMENT_DYNAMIC_CLASS(wxCURHandler, wxICOHandler)
 
 bool wxCURHandler::DoCanRead(wxInputStream& stream)
 {
 
 bool wxCURHandler::DoCanRead(wxInputStream& stream)
 {

-    if (stream.SeekI(0) == wxInvalidOffset)
-        return false;
-    unsigned char hdr[4];
-    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
-        return false;
-
-    // hdr[2] is one for an icon and two for a cursor
-    return hdr[0] == '\0' && hdr[1] == '\0' && hdr[2] == '\2' && hdr[3] == '\0';
+    return CanReadICOOrCUR(&stream, 2 /*for identifying a cursor*/);

 }
 
 #endif // wxUSE_STREAMS
 }
 
 #endif // wxUSE_STREAMS


@@ -1408,17 +1555,38 @@ bool wxANIHandler::DoCanRead(wxInputStream& stream)
 {
     wxANIDecoder decod;
     return decod.CanRead(stream);
 {
     wxANIDecoder decod;
     return decod.CanRead(stream);

+             // it's ok to modify the stream position here

 }
 
 }
 

-int wxANIHandler::GetImageCount(wxInputStream& stream)
+int wxANIHandler::DoGetImageCount(wxInputStream& stream)

 {
     wxANIDecoder decoder;
 {
     wxANIDecoder decoder;

-    if (!decoder.Load(stream))
+    if (!decoder.Load(stream))  // it's ok to modify the stream position here

         return wxNOT_FOUND;
 
     return decoder.GetFrameCount();
 }
 
         return wxNOT_FOUND;
 
     return decoder.GetFrameCount();
 }
 

+static bool CanReadICOOrCUR(wxInputStream *stream, wxUint16 resourceType)
+{
+    // It's ok to modify the stream position in this function.
+
+    if ( stream->IsSeekable() && stream->SeekI(0) == wxInvalidOffset )
+    {
+        return false;
+    }
+
+    ICONDIR iconDir;
+    if ( !stream->ReadAll(&iconDir, sizeof(iconDir)) )
+    {
+        return false;
+    }
+
+    return !iconDir.idReserved // reserved, must be 0
+        && wxUINT16_SWAP_ON_BE(iconDir.idType) == resourceType // either 1 or 2
+        && iconDir.idCount; // must contain at least one image
+}
+

 #endif // wxUSE_STREAMS
 
 #endif // wxUSE_ICO_CUR
 #endif // wxUSE_STREAMS
 
 #endif // wxUSE_ICO_CUR