screen: don't force the type of internal data

The win32 uses 2 different types with the same name. In C++ this breaks the
One Definition Rule.

modules/access/screen/dxgi.cpp

@@ -37,7 +37,8 @@
 #include <wrl/client.h>
 using Microsoft::WRL::ComPtr;
 
-struct screen_data_t
+namespace {
+struct dxgi_screen
 {
     const d3d_format_t             *output_format = nullptr;
     vlc_video_context              *vctx = nullptr;
@@ -47,12 +48,13 @@ struct screen_data_t
 
     ComPtr<IDXGIOutputDuplication> duplication;
 
-    ~screen_data_t()
+    ~dxgi_screen()
     {
         if (vctx)
             vlc_video_context_Release(vctx);
     }
 };
+} // namespace
 
 static void CaptureBlockRelease( block_t *p_block )
 {
@@ -64,7 +66,7 @@ static void CaptureBlockRelease( block_t *p_block )
 static block_t *screen_Capture(demux_t *p_demux)
 {
     demux_sys_t *p_sys = static_cast<demux_sys_t*>(p_demux->p_sys);
-    screen_data_t *p_data = p_sys->p_data;
+    dxgi_screen *p_data = static_cast<dxgi_screen *>(p_sys->p_data);
     block_sys_d3d11_t *d3d11_block = new (std::nothrow) block_sys_d3d11_t();
     ComPtr<IDXGIResource> resource;
     ComPtr<ID3D11Resource> d3d11res;
@@ -151,15 +153,16 @@ error:
     return nullptr;
 }
 
-static void screen_CloseCapture(screen_data_t *p_data)
+static void screen_CloseCapture(void *opaque)
 {
+    dxgi_screen *p_data = static_cast<dxgi_screen*>(opaque);
     delete p_data;
 }
 
 int screen_InitCaptureDXGI(demux_t *p_demux)
 {
     demux_sys_t *p_sys = static_cast<demux_sys_t*>(p_demux->p_sys);
-    screen_data_t *p_data;
+    dxgi_screen *p_data;
     vlc_decoder_device *dec_dev;
     HRESULT hr;
 
@@ -185,7 +188,7 @@ int screen_InitCaptureDXGI(demux_t *p_demux)
     }
 #endif // !WINAPI_PARTITION_DESKTOP
 
-    p_data = new (std::nothrow) screen_data_t();
+    p_data = new (std::nothrow) dxgi_screen();
     if (unlikely(p_data == nullptr))
         return VLC_ENOMEM;
 

modules/access/screen/mac.c

@@ -42,11 +42,11 @@
 extern int CGSMainConnectionID();
 extern CGImageRef CGSCreateRegisteredCursorImage(int, char*, CGPoint*);
 
-static void screen_CloseCapture(screen_data_t *);
+static void screen_CloseCapture(void *);
 static block_t *screen_Capture(demux_t *);
 
 
-struct screen_data_t
+typedef struct
 {
     block_t *p_block;
 
@@ -66,7 +66,7 @@ struct screen_data_t
     CGRect offscreen_rect;
     void *offscreen_bitmap;
     size_t offscreen_bitmap_size;
-};
+} screen_data_t;
 
 int screen_InitCapture(demux_t *p_demux)
 {
@@ -148,8 +148,9 @@ int screen_InitCapture(demux_t *p_demux)
     return VLC_SUCCESS;
 }
 
-static void screen_CloseCapture(screen_data_t *p_data)
+static void screen_CloseCapture(void *opaque)
 {
+    screen_data_t *p_data = opaque;
     if (p_data->offscreen_context)
         CFRelease(p_data->offscreen_context);
 

modules/access/screen/screen.h

@@ -34,12 +34,10 @@
 extern "C" {
 #endif
 
-typedef struct screen_data_t screen_data_t;
-
 struct screen_capture_operations
 {
     block_t* (*capture)( demux_t * );
-    void (*close)( screen_data_t * );
+    void (*close)( void * );
 };
 
 typedef struct
@@ -69,7 +67,7 @@ typedef struct
     picture_t dst;
 #endif
 
-    screen_data_t *p_data;
+    void *p_data;
     const struct screen_capture_operations *ops;
 } demux_sys_t;
 

modules/access/screen/win32.c

@@ -38,10 +38,10 @@
 #include <windows.h>
 
 
-static void screen_CloseCapture(screen_data_t *);
+static void screen_CloseCapture(void *);
 static block_t *screen_Capture(demux_t *);
 
-struct screen_data_t
+typedef struct
 {
     HDC hdc_src;
     HDC hdc_dst;
@@ -57,7 +57,7 @@ struct screen_data_t
 #ifdef SCREEN_MOUSE
     filter_t *p_blend;
 #endif
-};
+} screen_data_t;
 
 #if defined(SCREEN_SUBSCREEN) || defined(SCREEN_MOUSE)
 /*
@@ -162,8 +162,9 @@ int screen_InitCaptureGDI( demux_t *p_demux )
     return VLC_SUCCESS;
 }
 
-void screen_CloseCapture( screen_data_t *p_data )
+void screen_CloseCapture( void *opaque )
 {
+    screen_data_t *p_data = opaque;
     if( p_data->p_block ) block_Release( p_data->p_block );
 
     if( p_data->hgdi_backup)