Vincent Povirk : windowscodecs: Add a WARN message when CreateDecoderFromStream fails.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: ad1d8adfeb57c8fd59b6088ad3880a4ad7b18995
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=ad1d8adfeb57c8fd59b6088ad3880a4ad7b18995

Author: Vincent Povirk <vincent at codeweavers.com>
Date:   Fri Aug 14 16:13:15 2009 -0500

windowscodecs: Add a WARN message when CreateDecoderFromStream fails.

---

 dlls/windowscodecs/imgfactory.c |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/dlls/windowscodecs/imgfactory.c b/dlls/windowscodecs/imgfactory.c
index ab85bca..6424e42 100644
--- a/dlls/windowscodecs/imgfactory.c
+++ b/dlls/windowscodecs/imgfactory.c
@@ -164,6 +164,21 @@ static HRESULT WINAPI ImagingFactory_CreateDecoderFromStream(
     }
     else
     {
+        if (WARN_ON(wincodecs))
+        {
+            LARGE_INTEGER seek;
+            BYTE data[4];
+            ULONG bytesread;
+
+            WARN("failed to load from a stream\n");
+
+            seek.QuadPart = 0;
+            res = IStream_Seek(pIStream, seek, STREAM_SEEK_SET, NULL);
+            if (SUCCEEDED(res))
+                res = IStream_Read(pIStream, data, 4, &bytesread);
+            if (SUCCEEDED(res))
+                WARN("first %i bytes of stream=%x %x %x %x\n", bytesread, data[0], data[1], data[2], data[3]);
+        }
         *ppIDecoder = NULL;
         return WINCODEC_ERR_COMPONENTNOTFOUND;
     }