Committing modified version of jwiesemann's patch (see #11223):

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

diff --git a/src/common/imagtga.cpp b/src/common/imagtga.cpp
index 6d65dd788929cad8b8961ce84ce6d51b8a61b747..62080d22c1f5490cb0d852ce9f6bf3e35f08ebcb 100644 (file)
--- a/src/common/imagtga.cpp
+++ b/src/common/imagtga.cpp
@@ -39,9 +39,10 @@
 // TGA error codes.
 enum
 {
-    wxTGA_OK = 0,
-    wxTGA_INVFORMAT = 1,
-    wxTGA_MEMERR = 2
+    wxTGA_OK,
+    wxTGA_INVFORMAT,
+    wxTGA_MEMERR,
+    wxTGA_IOERR
 };
 
 // TGA header bytes.
@@ -100,8 +101,9 @@ void FlipTGA(unsigned char* imageData, int width, int height, short pixelSize)
     }
 }
 
+// return wxTGA_OK or wxTGA_IOERR
 static
-void DecodeRLE(unsigned char* imageData, unsigned long imageSize,
+int DecodeRLE(unsigned char* imageData, unsigned long imageSize,
                short pixelSize, wxInputStream& stream)
 {
     unsigned long index = 0;
@@ -111,7 +113,11 @@ void DecodeRLE(unsigned char* imageData, unsigned long imageSize,
 
     while (index < imageSize)
     {
-        current = stream.GetC();
+        int ch = stream.GetC();
+        if ( ch == wxEOF )
+            return wxTGA_IOERR;
+
+        current = ch;
 
         // RLE packet.
         if ( current & 0x80 )
@@ -126,7 +132,8 @@ void DecodeRLE(unsigned char* imageData, unsigned long imageSize,
             index += current * pixelSize;
 
             // Repeat the pixel length times.
-            stream.Read(buf, pixelSize);
+            if ( !stream.Read(buf, pixelSize) )
+                return wxTGA_IOERR;
 
             for (unsigned int i = 0; i < length; i++)
             {
@@ -145,11 +152,14 @@ void DecodeRLE(unsigned char* imageData, unsigned long imageSize,
             index += length;
 
             // Write the next length pixels directly to the image data.
-            stream.Read(imageData, length);
+            if ( !stream.Read(imageData, length) )
+                return wxTGA_IOERR;
 
             imageData += length;
         }
     }
+
+    return wxTGA_OK;
 }
 
 static
@@ -201,7 +211,8 @@ int ReadTGA(wxImage* image, wxInputStream& stream)
     }
 
     // Seek from the offset we got from the TGA header.
-    stream.SeekI(offset, wxFromStart);
+    if (stream.SeekI(offset, wxFromStart) == wxInvalidOffset)
+        return wxTGA_INVFORMAT;
 
     // Load a palette if we have one.
     if (colorType == wxTGA_MAPPED)
@@ -442,7 +453,9 @@ int ReadTGA(wxImage* image, wxInputStream& stream)
 
             // Decode the RLE data.
 
-            DecodeRLE(imageData, imageSize, pixelSize, stream);
+            int rc =  DecodeRLE(imageData, imageSize, pixelSize, stream);
+            if ( rc != wxTGA_OK )
+                return rc;
 
             // If orientation == 0, then the image is stored upside down.
             // We need to store it right side up.
@@ -500,7 +513,9 @@ int ReadTGA(wxImage* image, wxInputStream& stream)
         {
             // Decode the RLE data.
 
-            DecodeRLE(imageData, imageSize, pixelSize, stream);
+            int rc = DecodeRLE(imageData, imageSize, pixelSize, stream);
+            if ( rc != wxTGA_OK )
+                return rc;
 
             // If orientation == 0, then the image is stored upside down.
             // We need to store it right side up.
@@ -578,7 +593,9 @@ int ReadTGA(wxImage* image, wxInputStream& stream)
         {
             // Decode the RLE data.
 
-            DecodeRLE(imageData, imageSize, pixelSize, stream);
+            int rc = DecodeRLE(imageData, imageSize, pixelSize, stream);
+            if ( rc != wxTGA_OK )
+                return rc;
 
             // If orientation == 0, then the image is stored upside down.
             // We need to store it right side up.
@@ -652,7 +669,9 @@ bool wxTGAHandler::LoadFile(wxImage* image,
     if ( !CanRead(stream) )
     {
         if ( verbose )
+        {
             wxLogError(wxT("TGA: this is not a TGA file."));
+        }
 
         return false;
     }
@@ -674,6 +693,10 @@ bool wxTGAHandler::LoadFile(wxImage* image,
                     wxLogError(wxT("TGA: couldn't allocate memory."));
                     break;
 
+                case wxTGA_IOERR:
+                    wxLogError(wxT("TGA: couldn't read image data."));
+                    break;
+
                 default:
                     wxLogError(wxT("TGA: unknown error!"));
             }
@@ -720,7 +743,7 @@ bool wxTGAHandler::DoCanRead(wxInputStream& stream)
 {
     // read the fixed-size TGA headers
     unsigned char hdr[HDR_SIZE];
-    stream.Read(hdr, HDR_SIZE);
+    stream.Read(hdr, HDR_SIZE);     // it's ok to modify the stream position here
 
     // Check wether we can read the file or not.