Start refactoring bundle behavior into BundleManager

This is step 1: Encapsulating the data.

Bug: webrtc:12837
Change-Id: I15df30dc294c90136a90b072608ed4c2e8925dcb
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/221602
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#34245}

pc/BUILD.gn

@@ -41,6 +41,7 @@ rtc_library("rtc_pc_base") {
   visibility = [ "*" ]
   defines = []
   sources = [
+    "bundle_manager.h",
     "channel.cc",
     "channel.h",
     "channel_interface.h",

pc/bundle_manager.h

@@ -0,0 +1,49 @@
+/*
+ *  Copyright 2021 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef PC_BUNDLE_MANAGER_H_
+#define PC_BUNDLE_MANAGER_H_
+
+#include <memory>
+#include <vector>
+
+#include "pc/session_description.h"
+
+namespace webrtc {
+// This class manages information about RFC 8843 BUNDLE bundles
+// in SDP descriptions.
+
+// This is a work-in-progress. Planned steps:
+// 1) Move all Bundle-related data structures from JsepTransport
+//  into this class.
+// 2) Move all Bundle-related functions into this class.
+// 3) Move remaining Bundle-related logic into this class.
+//    Make data members private.
+// 4) Refine interface to have comprehensible semantics.
+// 5) Add unit tests.
+// 6) Change the logic to do what's right.
+class BundleManager {
+ public:
+  const std::vector<std::unique_ptr<cricket::ContentGroup>>& bundle_groups()
+      const {
+    return bundle_groups_;
+  }
+  std::vector<std::unique_ptr<cricket::ContentGroup>>& bundle_groups() {
+    return bundle_groups_;
+  }
+
+ private:
+  // Use unique_ptr<> to get a stable address.
+  std::vector<std::unique_ptr<cricket::ContentGroup>> bundle_groups_;
+};
+
+}  // namespace webrtc
+
+#endif  // PC_BUNDLE_MANAGER_H_

pc/jsep_transport_controller.cc

@@ -559,7 +559,7 @@ RTCError JsepTransportController::ApplyDescription_n(
   // Established BUNDLE groups by MID.
   std::map<std::string, cricket::ContentGroup*>
       established_bundle_groups_by_mid;
-  for (const auto& bundle_group : bundle_groups_) {
+  for (const auto& bundle_group : bundles_.bundle_groups()) {
     for (const std::string& content_name : bundle_group->content_names()) {
       established_bundle_groups_by_mid[content_name] = bundle_group.get();
     }
@@ -567,7 +567,7 @@ RTCError JsepTransportController::ApplyDescription_n(
 
   std::map<const cricket::ContentGroup*, std::vector<int>>
       merged_encrypted_extension_ids_by_bundle;
-  if (!bundle_groups_.empty()) {
+  if (!bundles_.bundle_groups().empty()) {
     merged_encrypted_extension_ids_by_bundle =
         MergeEncryptedHeaderExtensionIdsForBundles(
             established_bundle_groups_by_mid, description);
@@ -593,7 +593,7 @@ RTCError JsepTransportController::ApplyDescription_n(
     const cricket::TransportInfo& transport_info =
         description->transport_infos()[i];
     if (content_info.rejected) {
-      // This may cause groups to be removed from |bundle_groups_| and
+      // This may cause groups to be removed from |bundles_.bundle_groups()| and
       // |established_bundle_groups_by_mid|.
       HandleRejectedContent(content_info, established_bundle_groups_by_mid);
       continue;
@@ -752,7 +752,7 @@ RTCError JsepTransportController::ValidateAndMaybeUpdateBundleGroups(
       }
     }
 
-    for (const auto& bundle_group : bundle_groups_) {
+    for (const auto& bundle_group : bundles_.bundle_groups()) {
       for (const std::string& content_name : bundle_group->content_names()) {
         // An answer that removes m= sections from pre-negotiated BUNDLE group
         // without rejecting it, is invalid.
@@ -778,14 +778,14 @@ RTCError JsepTransportController::ValidateAndMaybeUpdateBundleGroups(
   }
 
   if (ShouldUpdateBundleGroup(type, description)) {
-    bundle_groups_.clear();
+    bundles_.bundle_groups().clear();
     for (const cricket::ContentGroup* new_bundle_group : new_bundle_groups) {
-      bundle_groups_.push_back(
+      bundles_.bundle_groups().push_back(
           std::make_unique<cricket::ContentGroup>(*new_bundle_group));
     }
   }
 
-  for (const auto& bundle_group : bundle_groups_) {
+  for (const auto& bundle_group : bundles_.bundle_groups()) {
     if (!bundle_group->FirstContentName())
       continue;
 
@@ -851,12 +851,12 @@ void JsepTransportController::HandleRejectedContent(
     }
     // Delete the BUNDLE group.
     auto bundle_group_it = std::find_if(
-        bundle_groups_.begin(), bundle_groups_.end(),
+        bundles_.bundle_groups().begin(), bundles_.bundle_groups().end(),
         [bundle_group](std::unique_ptr<cricket::ContentGroup>& group) {
           return bundle_group == group.get();
         });
-    RTC_DCHECK(bundle_group_it != bundle_groups_.end());
+    RTC_DCHECK(bundle_group_it != bundles_.bundle_groups().end());
-    bundle_groups_.erase(bundle_group_it);
+    bundles_.bundle_groups().erase(bundle_group_it);
   } else {
     RemoveTransportForMid(content_info.name);
     if (bundle_group) {
@@ -990,7 +990,7 @@ JsepTransportController::MergeEncryptedHeaderExtensionIdsForBundles(
     const std::map<std::string, cricket::ContentGroup*>& bundle_groups_by_mid,
     const cricket::SessionDescription* description) {
   RTC_DCHECK(description);
-  RTC_DCHECK(!bundle_groups_.empty());
+  RTC_DCHECK(!bundles_.bundle_groups().empty());
   std::map<const cricket::ContentGroup*, std::vector<int>>
       merged_encrypted_extension_ids_by_bundle;
   // Union the encrypted header IDs in the group when bundle is enabled.

pc/jsep_transport_controller.h

@@ -44,6 +44,7 @@
 #include "p2p/base/port_allocator.h"
 #include "p2p/base/transport_description.h"
 #include "p2p/base/transport_info.h"
+#include "pc/bundle_manager.h"
 #include "pc/channel.h"
 #include "pc/dtls_srtp_transport.h"
 #include "pc/dtls_transport.h"
@@ -483,14 +484,13 @@ class JsepTransportController : public sigslot::has_slots<> {
   const cricket::SessionDescription* remote_desc_ = nullptr;
   absl::optional<bool> initial_offerer_;
 
-  // Use unique_ptr<> to get a stable address.
-  std::vector<std::unique_ptr<cricket::ContentGroup>> bundle_groups_;
-
   cricket::IceConfig ice_config_;
   cricket::IceRole ice_role_ = cricket::ICEROLE_CONTROLLING;
   uint64_t ice_tiebreaker_ = rtc::CreateRandomId64();
   rtc::scoped_refptr<rtc::RTCCertificate> certificate_;
 
+  BundleManager bundles_;
+
   RTC_DISALLOW_COPY_AND_ASSIGN(JsepTransportController);
 };