* include/errors.h: New file.

* include/dshow.h: Include <errors.h>.

winsup/w32api/include/errors.h

@@ -0,0 +1,23 @@
+#ifndef _ERRORS_H
+#define _ERRORS_H
+#if __GNUC__ >=3
+#pragma GCC system_header
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define MAX_ERROR_TEXT_LEN 160
+DWORD WINAPI AMGetErrorTextA(HRESULT,CHAR*,DWORD);
+DWORD WINAPI AMGetErrorTextW(HRESULT,WCHAR*,DWORD);
+#ifdef UNICODE
+#define AMGetErrorText AMGetErrorTextW
+#else
+#define AMGetErrorText AMGetErrorTextA
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+#endif