[PATCH v3 1/5] dcc: Check to see if the client supports multiple codecs (v2)

[Vivek Kasireddy <vivek.kasireddy@xxxxxxxxx>]

We need to determine if the client is new enough to support multiple
codecs -- which might include any of the Gstreamer based ones.

v2: (suggestions and fixups from Frediano)
- Add is_gl_client() method to DisplayChannelClient instead of a
  dcc_is_gl_client() function.
- Avoid the usage of XXX_CAST macro.

Cc: Frediano Ziglio <freddy77@xxxxxxxxx>
Cc: Gerd Hoffmann <kraxel@xxxxxxxxxx>
Cc: Marc-André Lureau <marcandre.lureau@xxxxxxxxxx>
Cc: Dongwon Kim <dongwon.kim@xxxxxxxxx>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@xxxxxxxxx>
---
 server/dcc.cpp | 22 ++++++++++++----------
 server/dcc.h   |  6 ++++++
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/server/dcc.cpp b/server/dcc.cpp
index 01c16ab7..ca73470a 100644
--- a/server/dcc.cpp
+++ b/server/dcc.cpp
@@ -494,29 +494,31 @@ RedSurfaceDestroyItem::RedSurfaceDestroyItem(uint32_t surface_id)
 
 RedPipeItemPtr dcc_gl_scanout_item_new(RedChannelClient *rcc, void *data, int num)
 {
-    /* FIXME: on !unix peer, start streaming with a video codec */
-    if (!red_stream_is_plain_unix(rcc->get_stream()) ||
-        !rcc->test_remote_cap(SPICE_DISPLAY_CAP_GL_SCANOUT)) {
+    auto dcc = static_cast<DisplayChannelClient *>(rcc);
+
+    if (dcc->is_gl_client()) {
+        return red::make_shared<RedGlScanoutUnixItem>();
+    } else if (rcc->test_remote_cap(SPICE_DISPLAY_CAP_MULTI_CODEC)) {
+        return RedPipeItemPtr();
+    } else {
         red_channel_warning(rcc->get_channel(),
-                            "FIXME: client does not support GL scanout");
+                            "Client does not support GL scanout or multiple codecs");
         rcc->disconnect();
         return RedPipeItemPtr();
     }
-
-    return red::make_shared<RedGlScanoutUnixItem>();
 }
 
 XXX_CAST(RedChannelClient, DisplayChannelClient, DISPLAY_CHANNEL_CLIENT);
 
 RedPipeItemPtr dcc_gl_draw_item_new(RedChannelClient *rcc, void *data, int num)
 {
-    DisplayChannelClient *dcc = DISPLAY_CHANNEL_CLIENT(rcc);
+    auto dcc = static_cast<DisplayChannelClient *>(rcc);
     auto draw = static_cast<const SpiceMsgDisplayGlDraw *>(data);
 
-    if (!red_stream_is_plain_unix(rcc->get_stream()) ||
-        !rcc->test_remote_cap(SPICE_DISPLAY_CAP_GL_SCANOUT)) {
+    if (!dcc->is_gl_client() &&
+        !rcc->test_remote_cap(SPICE_DISPLAY_CAP_MULTI_CODEC)) {
         red_channel_warning(rcc->get_channel(),
-                            "FIXME: client does not support GL scanout");
+                            "Client does not support GL scanout or multiple codecs");
         rcc->disconnect();
         return RedPipeItemPtr();
     }
diff --git a/server/dcc.h b/server/dcc.h
index a8dd3bef..47f082fe 100644
--- a/server/dcc.h
+++ b/server/dcc.h
@@ -47,6 +47,12 @@ public:
                          spice_wan_compression_t zlib_glz_state);
     virtual void disconnect() override;
 
+    bool is_gl_client()
+    {
+        return red_stream_is_plain_unix(get_stream()) &&
+           test_remote_cap(SPICE_DISPLAY_CAP_GL_SCANOUT);
+    }
+
 protected:
     virtual bool handle_message(uint16_t type, uint32_t size, void *msg) override;
     virtual bool config_socket() override;
-- 
2.39.2