avfilter: factorize requesting an input frame from multi output filters

Signed-off-by: Marton Balint <cus@passwd.hu>

6 files changed, 20 insertions, 36 deletions

diff --git a/doc/filter_design.txt b/doc/filter_design.txt
index 885b19b6f6..b6bfca12f5 100644
--- a/doc/filter_design.txt
+++ b/doc/filter_design.txt
@@ -214,6 +214,7 @@ Frame scheduling
     FF_FILTER_FORWARD_STATUS(inlink, outlink);
     FF_FILTER_FORWARD_STATUS_ALL(inlink, filter);
     FF_FILTER_FORWARD_WANTED(outlink, inlink);
+    FF_FILTER_FORWARD_WANTED_ANY(filter, inlink);
 
   filter_frame
   ------------
diff --git a/libavfilter/af_acrossover.c b/libavfilter/af_acrossover.c
index 2c9a1e00bc..e24bf9eb73 100644
--- a/libavfilter/af_acrossover.c
+++ b/libavfilter/af_acrossover.c
@@ -588,15 +588,7 @@ static int activate(AVFilterContext *ctx)
         return 0;
     }
 
-    for (int i = 0; i < ctx->nb_outputs; i++) {
-        if (ff_outlink_get_status(ctx->outputs[i]))
-            continue;
-
-        if (ff_outlink_frame_wanted(ctx->outputs[i])) {
-            ff_inlink_request_frame(inlink);
-            return 0;
-        }
-    }
+    FF_FILTER_FORWARD_WANTED_ANY(ctx, inlink);
 
     return FFERROR_NOT_READY;
 }
diff --git a/libavfilter/af_channelsplit.c b/libavfilter/af_channelsplit.c
index 0156c0c28c..638e81593c 100644
--- a/libavfilter/af_channelsplit.c
+++ b/libavfilter/af_channelsplit.c
@@ -228,15 +228,7 @@ static int activate(AVFilterContext *ctx)
         return 0;
     }
 
-    for (int i = 0; i < ctx->nb_outputs; i++) {
-        if (ff_outlink_get_status(ctx->outputs[i]))
-            continue;
-
-        if (ff_outlink_frame_wanted(ctx->outputs[i])) {
-            ff_inlink_request_frame(inlink);
-            return 0;
-        }
-    }
+    FF_FILTER_FORWARD_WANTED_ANY(ctx, inlink);
 
     return FFERROR_NOT_READY;
 }
diff --git a/libavfilter/filters.h b/libavfilter/filters.h
index 654aed5c9e..66dc611a98 100644
--- a/libavfilter/filters.h
+++ b/libavfilter/filters.h
@@ -697,6 +697,21 @@ static inline void ff_outlink_set_status(AVFilterLink *link, int status, int64_t
 } while (0)
 
 /**
+ * Forward the frame_wanted_out flag from any of the output links to an input link.
+ * If the flag is set on any of the outputs, this macro will return immediately.
+ */
+#define FF_FILTER_FORWARD_WANTED_ANY(filter, inlink) do { \
+    for (int i = 0; i < filter->nb_outputs; i++) { \
+        if (ff_outlink_get_status(filter->outputs[i])) \
+            continue; \
+        if (ff_outlink_frame_wanted(filter->outputs[i])) { \
+            ff_inlink_request_frame(inlink); \
+            return 0; \
+        } \
+    } \
+} while (0)
+
+/**
  * Check for flow control between input and output.
  * This is necessary for filters that may produce several output frames for
  * a single input event, otherwise they may produce them all at once,
diff --git a/libavfilter/split.c b/libavfilter/split.c
index 0557f54cce..d0bd0c3b2a 100644
--- a/libavfilter/split.c
+++ b/libavfilter/split.c
@@ -110,15 +110,7 @@ static int activate(AVFilterContext *ctx)
         return 0;
     }
 
-    for (int i = 0; i < ctx->nb_outputs; i++) {
-        if (ff_outlink_get_status(ctx->outputs[i]))
-            continue;
-
-        if (ff_outlink_frame_wanted(ctx->outputs[i])) {
-            ff_inlink_request_frame(inlink);
-            return 0;
-        }
-    }
+    FF_FILTER_FORWARD_WANTED_ANY(ctx, inlink);
 
     return FFERROR_NOT_READY;
 }
diff --git a/libavfilter/vf_extractplanes.c b/libavfilter/vf_extractplanes.c
index 337ad12ac7..99e37ba04a 100644
--- a/libavfilter/vf_extractplanes.c
+++ b/libavfilter/vf_extractplanes.c
@@ -367,15 +367,7 @@ static int activate(AVFilterContext *ctx)
         return 0;
     }
 
-    for (int i = 0; i < ctx->nb_outputs; i++) {
-        if (ff_outlink_get_status(ctx->outputs[i]))
-            continue;
-
-        if (ff_outlink_frame_wanted(ctx->outputs[i])) {
-            ff_inlink_request_frame(inlink);
-            return 0;
-        }
-    }
+    FF_FILTER_FORWARD_WANTED_ANY(ctx, inlink);
 
     return FFERROR_NOT_READY;
 }