From 721d17e1818a82c6b3fdf9468ec82938e91969a8 Mon Sep 17 00:00:00 2001
From: Edward Hervey <edward@centricular.com>
Date: Sat, 15 Apr 2023 08:17:09 +0200
Subject: [PATCH] rtpgccbwe: Don't process empty lists

The structure parsing could result in an empty vector. Don't do any processing
since the loss code assumes it's non-empty for average estimates which would
result in weird/invalid results.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1181>
---
 net/rtp/src/gcc/imp.rs | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/net/rtp/src/gcc/imp.rs b/net/rtp/src/gcc/imp.rs
index 479198ac..f56d0a78 100644
--- a/net/rtp/src/gcc/imp.rs
+++ b/net/rtp/src/gcc/imp.rs
@@ -1184,19 +1184,22 @@ impl ObjectSubclass for BandwidthEstimator {
                                     })
                                     .collect::<Vec<Packet>>();
 
-                                let bitrate_changed = {
-                                    let mut state = this.state.lock().unwrap();
+                                // The list of packets could be empty once parsed
+                                if !packets.is_empty() {
+                                    let bitrate_changed = {
+                                        let mut state = this.state.lock().unwrap();
 
-                                    state.detector.update(&mut packets);
-                                    if !state.delay_control(&bwe) {
-                                        state.loss_control(&bwe)
-                                    } else {
-                                        true
+                                        state.detector.update(&mut packets);
+                                        if !state.delay_control(&bwe) {
+                                            state.loss_control(&bwe)
+                                        } else {
+                                            true
+                                        }
+                                    };
+
+                                    if bitrate_changed {
+                                        bwe.notify("estimated-bitrate")
                                     }
-                                };
-
-                                if bitrate_changed {
-                                    bwe.notify("estimated-bitrate")
                                 }
                             }
                         }