video: refactor how VO exports hwdec device handles

The main change is with video/hwdec.h. mp_hwdec_info is made opaque (and
renamed to mp_hwdec_devices). Its accessors are mainly thread-safe (or
documented where not), which makes the whole thing saner and cleaner. In
particular, thread-safety rules become less subtle and more obvious.

The new internal API makes it easier to support multiple OpenGL interop
backends. (Although this is not done yet, and it's not clear whether it
ever will.)

This also removes all the API-specific fields from mp_hwdec_ctx and
replaces them with a "ctx" field. For d3d in particular, we drop the
mp_d3d_ctx struct completely, and pass the interfaces directly.

Remove the emulation checks from vaapi.c and vdpau.c; they are
pointless, and the checks that matter are done on the VO layer.

The d3d hardware decoders might slightly change behavior: dxva2-copy
will not use the VO device anymore if the VO supports proper interop.
This pretty much assumes that any in such cases the VO will not use any
form of exclusive mode, which makes using the VO device in copy mode
unnecessary.

This is a big refactor. Some things may be untested and could be broken.

5 files changed, 11 insertions, 21 deletions

diff --git a/video/filter/vf.c b/video/filter/vf.c
index d8e7f6b4c8..7ca1b08f34 100644
--- a/video/filter/vf.c
+++ b/video/filter/vf.c
@@ -244,7 +244,7 @@ static struct vf_instance *vf_open(struct vf_chain *c, const char *name,
     *vf = (vf_instance_t) {
         .info = desc.p,
         .log = mp_log_new(vf, c->log, name),
-        .hwdec = c->hwdec,
+        .hwdec_devs = c->hwdec_devs,
         .query_format = vf_default_query_format,
         .out_pool = talloc_steal(vf, mp_image_pool_new(16)),
         .chain = c,
diff --git a/video/filter/vf.h b/video/filter/vf.h
index c982b612e1..02f6f2c8fd 100644
--- a/video/filter/vf.h
+++ b/video/filter/vf.h
@@ -92,7 +92,7 @@ typedef struct vf_instance {
     struct mp_image_pool *out_pool;
     struct vf_priv_s *priv;
     struct mp_log *log;
-    struct mp_hwdec_info *hwdec;
+    struct mp_hwdec_devices *hwdec_devs;
 
     struct mp_image **out_queued;
     int num_out_queued;
@@ -120,7 +120,7 @@ struct vf_chain {
     struct mp_log *log;
     struct MPOpts *opts;
     struct mpv_global *global;
-    struct mp_hwdec_info *hwdec;
+    struct mp_hwdec_devices *hwdec_devs;
 
     // Call when the filter chain wants new processing (for filters with
     // asynchronous behavior) - must be immutable once filters are created,
diff --git a/video/filter/vf_vavpp.c b/video/filter/vf_vavpp.c
index 9dab15e2b9..554ddc1a05 100644
--- a/video/filter/vf_vavpp.c
+++ b/video/filter/vf_vavpp.c
@@ -481,19 +481,17 @@ static bool initialize(struct vf_instance *vf)
 
 static int vf_open(vf_instance_t *vf)
 {
+    struct vf_priv_s *p = vf->priv;
+
     vf->reconfig = reconfig;
     vf->filter_ext = filter_ext;
     vf->query_format = query_format;
     vf->uninit = uninit;
     vf->control = control;
 
-    struct vf_priv_s *p = vf->priv;
-    if (!vf->hwdec)
-        return false;
-    hwdec_request_api(vf->hwdec, "vaapi");
-    p->va = vf->hwdec->hwctx ? vf->hwdec->hwctx->vaapi_ctx : NULL;
-    if (!p->va || !p->va->display)
-        return false;
+    p->va = hwdec_devices_load(vf->hwdec_devs, HWDEC_VAAPI);
+    if (!p->va)
+        return 0;
     p->display = p->va->display;
     if (initialize(vf))
         return true;
diff --git a/video/filter/vf_vdpaupp.c b/video/filter/vf_vdpaupp.c
index 882b80d9e2..23afeafe6a 100644
--- a/video/filter/vf_vdpaupp.c
+++ b/video/filter/vf_vdpaupp.c
@@ -223,10 +223,7 @@ static int vf_open(vf_instance_t *vf)
     vf->control = control;
     vf->uninit = uninit;
 
-    if (!vf->hwdec)
-        return 0;
-    hwdec_request_api(vf->hwdec, "vdpau");
-    p->ctx = vf->hwdec->hwctx ? vf->hwdec->hwctx->vdpau_ctx : NULL;
+    p->ctx = hwdec_devices_load(vf->hwdec_devs, HWDEC_VDPAU);
     if (!p->ctx)
         return 0;
 
diff --git a/video/filter/vf_vdpaurb.c b/video/filter/vf_vdpaurb.c
index 62f7f34af1..92dfa52486 100644
--- a/video/filter/vf_vdpaurb.c
+++ b/video/filter/vf_vdpaurb.c
@@ -101,14 +101,9 @@ static int vf_open(vf_instance_t *vf)
     vf->reconfig = reconfig;
     vf->query_format = query_format;
 
-    if (!vf->hwdec) {
+    p->ctx = hwdec_devices_load(vf->hwdec_devs, HWDEC_VDPAU);
+    if (!p->ctx)
         return 0;
-    }
-    hwdec_request_api(vf->hwdec, "vdpau");
-    p->ctx = vf->hwdec->hwctx ? vf->hwdec->hwctx->vdpau_ctx : NULL;
-    if (!p->ctx) {
-        return 0;
-    }
 
     return 1;
 }