Revert "avutils/hwcontext: When deriving a hwdevice, search for existing device in both directions"

This reverts commit a4289497755386435783774a4f520eb7fc23cbc9.
There were objections on ML (see
https://ffmpeg.org/pipermail/ffmpeg-devel/2021-December/290530.html)

Signed-off-by: Haihao Xiang <haihao.xiang@intel.com>

1 files changed, 0 insertions, 38 deletions

diff --git a/libavutil/hwcontext.c b/libavutil/hwcontext.c
index 1a50635018..31c7840dba 100644
--- a/libavutil/hwcontext.c
+++ b/libavutil/hwcontext.c
@@ -122,7 +122,6 @@ static const AVClass hwdevice_ctx_class = {
 static void hwdevice_ctx_free(void *opaque, uint8_t *data)
 {
     AVHWDeviceContext *ctx = (AVHWDeviceContext*)data;
-    int i;
 
     /* uninit might still want access the hw context and the user
      * free() callback might destroy it, so uninit has to be called first */
@@ -133,8 +132,6 @@ static void hwdevice_ctx_free(void *opaque, uint8_t *data)
         ctx->free(ctx);
 
     av_buffer_unref(&ctx->internal->source_device);
-    for (i = 0; i < AV_HWDEVICE_TYPE_NB; i++)
-        av_buffer_unref(&ctx->internal->derived_devices[i]);
 
     av_freep(&ctx->hwctx);
     av_freep(&ctx->internal->priv);
@@ -646,26 +643,6 @@ fail:
     return ret;
 }
 
-static AVBufferRef* find_derived_hwdevice_ctx(AVBufferRef *src_ref, enum AVHWDeviceType type)
-{
-    AVBufferRef *tmp_ref;
-    AVHWDeviceContext *src_ctx;
-    int i;
-
-    src_ctx = (AVHWDeviceContext*)src_ref->data;
-    if (src_ctx->type == type)
-        return src_ref;
-
-    for (i = 0; i < AV_HWDEVICE_TYPE_NB; i++)
-        if (src_ctx->internal->derived_devices[i]) {
-            tmp_ref = find_derived_hwdevice_ctx(src_ctx->internal->derived_devices[i], type);
-            if (tmp_ref)
-                return tmp_ref;
-        }
-
-    return NULL;
-}
-
 int av_hwdevice_ctx_create_derived_opts(AVBufferRef **dst_ref_ptr,
                                         enum AVHWDeviceType type,
                                         AVBufferRef *src_ref,
@@ -689,16 +666,6 @@ int av_hwdevice_ctx_create_derived_opts(AVBufferRef **dst_ref_ptr,
         tmp_ref = tmp_ctx->internal->source_device;
     }
 
-    tmp_ref = find_derived_hwdevice_ctx(src_ref, type);
-    if (tmp_ref) {
-        dst_ref = av_buffer_ref(tmp_ref);
-        if (!dst_ref) {
-            ret = AVERROR(ENOMEM);
-            goto fail;
-        }
-        goto done;
-    }
-
     dst_ref = av_hwdevice_ctx_alloc(type);
     if (!dst_ref) {
         ret = AVERROR(ENOMEM);
@@ -720,11 +687,6 @@ int av_hwdevice_ctx_create_derived_opts(AVBufferRef **dst_ref_ptr,
                     ret = AVERROR(ENOMEM);
                     goto fail;
                 }
-                tmp_ctx->internal->derived_devices[type] = av_buffer_ref(dst_ref);
-                if (!tmp_ctx->internal->derived_devices[type]) {
-                    ret = AVERROR(ENOMEM);
-                    goto fail;
-                }
                 ret = av_hwdevice_ctx_init(dst_ref);
                 if (ret < 0)
                     goto fail;