Rewind the input stream after failing to load image from it.

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

diff --git a/src/common/imagpnm.cpp b/src/common/imagpnm.cpp
index e46916c549379feb82e1ca647af31d9ec55e97e7..731220450b67e54121d9216ecd872b9528666191 100644 (file)
--- a/src/common/imagpnm.cpp
+++ b/src/common/imagpnm.cpp
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        imagpnm.cpp
+// Name:        src/common/imagpnm.cpp

 // Purpose:     wxImage PNM handler
 // Author:      Sylvain Bougnoux
 // RCS-ID:      $Id$
 // Purpose:     wxImage PNM handler
 // Author:      Sylvain Bougnoux
 // RCS-ID:      $Id$


@@ -7,154 +7,210 @@
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 

-/*
-   We don't put pragma implement in this file because it is already present in
-   src/common/image.cpp
-*/
-

 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
 #ifdef __BORLANDC__
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
 #ifdef __BORLANDC__

-#pragma hdrstop
+    #pragma hdrstop

 #endif
 
 #endif
 

-#include "wx/image.h"
-#include "wx/log.h"
-#include "wx/txtstrm.h"
+#if wxUSE_IMAGE && wxUSE_PNM

 
 

-#ifdef __WXMSW__
-#include <windows.h>
+#include "wx/imagpnm.h"
+
+#ifndef WX_PRECOMP
+    #include "wx/intl.h"
+    #include "wx/log.h"

 #endif
 
 #endif
 

+#include "wx/txtstrm.h"
+

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

-#if !USE_SHARED_LIBRARIES

 IMPLEMENT_DYNAMIC_CLASS(wxPNMHandler,wxImageHandler)
 IMPLEMENT_DYNAMIC_CLASS(wxPNMHandler,wxImageHandler)

-#endif

 
 #if wxUSE_STREAMS
 
 
 #if wxUSE_STREAMS
 

-  //#include <stream.h> // for cout
-

 void Skip_Comment(wxInputStream &stream)
 {
 void Skip_Comment(wxInputStream &stream)
 {

-  wxString line;
-  wxTextInputStream text_stream(stream);
+    wxTextInputStream text_stream(stream);

 
 

-  if (stream.Peek()==_T('#')) 
+    if (stream.Peek()==wxT('#'))

     {
     {

-      text_stream >> line;
-      Skip_Comment(stream);
+        text_stream.ReadLine();
+        Skip_Comment(stream);

     }
 }
 
     }
 }
 

-bool wxPNMHandler::LoadFile( wxImage *image, wxInputStream& stream, bool WXUNUSED(verbose) )
+bool wxPNMHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int WXUNUSED(index) )

 {
     wxUint32  width, height;
     wxUint16  maxval;
 {
     wxUint32  width, height;
     wxUint16  maxval;

-    wxString  line;

     char      c(0);
     char      c(0);

-    
+

     image->Destroy();
 
     /*
      * Read the PNM header
      */
 
     image->Destroy();
 
     /*
      * Read the PNM header
      */
 

-    wxTextInputStream text_stream(stream);
+    wxBufferedInputStream buf_stream(stream);
+    wxTextInputStream text_stream(buf_stream);

 
 

-    Skip_Comment(stream);
-    if (stream.GetC()==_T('P')) c=stream.GetC();
+    Skip_Comment(buf_stream);
+    if (buf_stream.GetC()==wxT('P')) c=buf_stream.GetC();

 
     switch (c)
 
     switch (c)

-      {
-      case _T('2'):
-       wxLogError(_T("Loading Grey Ascii PNM image is not yet implemented."));
-       return FALSE;
-      case _T('5'):
-       wxLogError(_T("Loading Grey Raw PNM image is not yet implemented."));
-       return FALSE;
-      case _T('3'): case _T('6'): break;
-       default :
-       wxLogError(_T("Loading PNM image : file not recognized."));
-       return FALSE;
-      }
-
-    text_stream >> line; // for the \n
-    Skip_Comment(stream);
+    {
+        case wxT('2'): // ASCII Grey
+        case wxT('3'): // ASCII RGB
+        case wxT('5'): // RAW Grey
+        case wxT('6'): break;
+        default:
+            if (verbose)
+            {
+                wxLogError(_("PNM: File format is not recognized."));
+            }
+            return false;
+    }
+
+    text_stream.ReadLine(); // for the \n
+    Skip_Comment(buf_stream);

     text_stream >> width >> height ;
     text_stream >> width >> height ;

-    Skip_Comment(stream); 
+    Skip_Comment(buf_stream);

     text_stream >> maxval;
 
     text_stream >> maxval;
 

-    //cout << width << " " << height << " " << maxval << endl;
+    //cout << line << " " << width << " " << height << " " << maxval << endl;

     image->Create( width, height );
     unsigned char *ptr = image->GetData();
     if (!ptr)
     {
     image->Create( width, height );
     unsigned char *ptr = image->GetData();
     if (!ptr)
     {

-        wxLogError( _T("Cannot allocate RAM for RGB data in PNM file.") );
-       return FALSE;
+        if (verbose)
+        {
+           wxLogError( _("PNM: Couldn't allocate memory.") );
+        }
+        return false;

     }
 
     }
 

+
+    if (c=='2') // Ascii GREY
+    {
+        wxUint32 value, size=width*height;
+        for (wxUint32 i=0; i<size; ++i)
+        {
+            value=text_stream.Read32();
+            if ( maxval != 255 )
+                value = (255 * value)/maxval;
+            *ptr++=(unsigned char)value; // R
+            *ptr++=(unsigned char)value; // G
+            *ptr++=(unsigned char)value; // B
+            if ( !buf_stream )
+            {
+                if (verbose)
+                {
+                    wxLogError(_("PNM: File seems truncated."));
+                }
+                return false;
+            }
+        }
+    }

     if (c=='3') // Ascii RBG
     if (c=='3') // Ascii RBG

-      { 
-       wxUint32 value, size=3*width*height;
-       for (wxUint32 i=0; i<size; ++i)
-         {
-           //this is very slow !!!
-           //I wonder how we can make any better ?
-           value=text_stream.Read32();
-           *ptr++=(unsigned char)value;
-
-           if (stream.LastError()!=wxSTREAM_NOERROR)
-             {
-               wxLogError(_T("Loading PNM image : file seems truncated."));
-               return FALSE;
-             }
-         }
-      }
-    if (c=='6') // Raw RGB
-      stream.Read( ptr, 3*width*height );
-
-    image->SetMask( FALSE );
-
-    return (stream.LastError()==wxStream_NOERROR || stream.LastError()==wxStream_EOF);
+    {
+        wxUint32 value, size=3*width*height;
+        for (wxUint32 i=0; i<size; ++i)
+          {
+            //this is very slow !!!
+            //I wonder how we can make any better ?
+            value=text_stream.Read32();
+            if ( maxval != 255 )
+                value = (255 * value)/maxval;
+            *ptr++=(unsigned char)value;
+
+            if ( !buf_stream )
+              {
+                if (verbose)
+                {
+                    wxLogError(_("PNM: File seems truncated."));
+                }
+                return false;
+              }
+          }
+    }
+    if (c=='5') // Raw GREY
+    {
+        wxUint32 size=width*height;
+        unsigned char value;
+        for (wxUint32 i=0; i<size; ++i)
+        {
+            buf_stream.Read(&value,1);
+            if ( maxval != 255 )
+                value = (255 * value)/maxval;
+            *ptr++=value; // R
+            *ptr++=value; // G
+            *ptr++=value; // B
+            if ( !buf_stream )
+            {
+                if (verbose)
+                {
+                    wxLogError(_("PNM: File seems truncated."));
+                }
+                return false;
+            }
+        }
+    }
+
+    if ( c=='6' ) // Raw RGB
+    {
+        buf_stream.Read(ptr, 3*width*height);
+        if ( maxval != 255 )
+        {
+            for ( unsigned i = 0; i < 3*width*height; i++ )
+                ptr[i] = (255 * ptr[i])/maxval;
+        }
+    }
+
+    image->SetMask( false );
+
+    const wxStreamError err = buf_stream.GetLastError();
+    return err == wxSTREAM_NO_ERROR || err == wxSTREAM_EOF;

 }
 
 bool wxPNMHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool WXUNUSED(verbose) )
 {
     wxTextOutputStream text_stream(stream);
 }
 
 bool wxPNMHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool WXUNUSED(verbose) )
 {
     wxTextOutputStream text_stream(stream);

-    
-    //text_stream << "P6" << endl 
-    //<< image->GetWidth() << " " << image->GetHeight() << endl 
+
+    //text_stream << "P6" << endl
+    //<< image->GetWidth() << " " << image->GetHeight() << endl

     //<< "255" << endl;
     //<< "255" << endl;

-    text_stream << "P6\n" << image->GetWidth() << " " << image->GetHeight() << "\n255\n";
+    text_stream << wxT("P6\n") << image->GetWidth() << wxT(" ") << image->GetHeight() << wxT("\n255\n");

     stream.Write(image->GetData(),3*image->GetWidth()*image->GetHeight());
 
     stream.Write(image->GetData(),3*image->GetWidth()*image->GetHeight());
 

-    return (stream.LastError()==wxStream_NOERROR);
+    return stream.IsOk();

 }
 
 }
 

-bool wxPNMHandler::CanRead( wxInputStream& stream )
+bool wxPNMHandler::DoCanRead( wxInputStream& stream )

 {
 {

-    off_t pos=stream.TellI();
-

     Skip_Comment(stream);
 
     Skip_Comment(stream);
 

-    if (stream.GetC()==_T('P'))
-      switch (stream.GetC())
-       {
-       case _T('3'): case _T('6'):
-         stream.SeekI(pos);
-         return TRUE;
-       }
+    // it's ok to modify the stream position here
+    if ( stream.GetC() == 'P' )
+    {
+        switch ( stream.GetC() )
+        {
+            case '2': // ASCII Grey
+            case '3': // ASCII RGB
+            case '5': // RAW Grey
+            case '6': // RAW RGB
+                return true;
+        }
+    }

 
 

-    stream.SeekI(pos);
-    return FALSE;
+    return false;

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

-
+#endif // wxUSE_IMAGE && wxUSE_PNM