console/win32: allocate shareable display surface

Introduce qemu_win32_map_alloc() and qemu_win32_map_free() to allocate
shared memory mapping. The handle can be used to share the mapping with
another process.

Teach qemu_create_displaysurface() to allocate shared memory. Following
patches will introduce other places for shared memory allocation.

Other patches for -display dbus will share the memory when possible with
the client, to avoid expensive memory copy between the processes.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20230606115658.677673-10-marcandre.lureau@redhat.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/ui/console.h b/include/ui/console.h
index 2093e2a3ba..2ab0c7112a 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -143,6 +143,10 @@ typedef struct DisplaySurface {
     GLenum gltype;
     GLuint texture;
 #endif
+#ifdef WIN32
+    HANDLE handle;
+    uint32_t handle_offset;
+#endif
 } DisplaySurface;
 
 typedef struct QemuUIInfo {
@@ -329,6 +333,10 @@ DisplaySurface *qemu_create_displaysurface_from(int width, int height,
 DisplaySurface *qemu_create_displaysurface_pixman(pixman_image_t *image);
 DisplaySurface *qemu_create_placeholder_surface(int w, int h,
                                                 const char *msg);
+#ifdef WIN32
+void qemu_displaysurface_win32_set_handle(DisplaySurface *surface,
+                                          HANDLE h, uint32_t offset);
+#endif
 PixelFormat qemu_default_pixelformat(int bpp);
 
 DisplaySurface *qemu_create_displaysurface(int width, int height);