Fix for 64-bit negative seek value.

files/file.c

@@ -1289,9 +1289,12 @@ DWORD WINAPI SetFilePointer( HANDLE hFile, LONG distance, LONG *highword,
 {
     struct set_file_pointer_request *req = get_req_buffer();
 
-    if (highword && *highword)
+    if (highword &&
+        ((distance >= 0 && *highword != 0) || (distance < 0 && *highword != -1)))
     {
-        FIXME("64-bit offsets not supported yet\n");
+        FIXME("64-bit offsets not supported yet\n"
+              "SetFilePointer(%08x,%08lx,%08lx,%08lx)\n",
+              hFile,distance,*highword,method);
         SetLastError( ERROR_INVALID_PARAMETER );
         return 0xffffffff;
     }
@@ -1300,7 +1303,7 @@ DWORD WINAPI SetFilePointer( HANDLE hFile, LONG distance, LONG *highword,
 
     req->handle = hFile;
     req->low = distance;
-    req->high = highword ? *highword : 0;
+    req->high = highword ? *highword : (distance >= 0) ? 0 : -1;
     /* FIXME: assumes 1:1 mapping between Windows and Unix seek constants */
     req->whence = method;
     SetLastError( 0 );

server/file.c

@@ -344,9 +344,9 @@ static int set_file_pointer( int handle, int *low, int *high, int whence )
     struct file *file;
     int result;
 
-    if (*high)
+    if ((*low >= 0 && *high != 0) || (*low < 0 && *high != -1))
     {
-        fprintf( stderr, "set_file_pointer: offset > 4Gb not supported yet\n" );
+        fprintf( stderr, "set_file_pointer: offset > 2Gb not supported yet\n" );
         set_error( STATUS_INVALID_PARAMETER );
         return 0;
     }