commit f3736ed3d8d4e6660ad8b82a8deff7aca8389e5c
author Harald Alvestrand <hta@webrtc.org> Mon Apr 08 13:09:30 2019 +0200
committer Commit Bot <commit-bot@chromium.org> Tue Apr 09 08:32:43 2019 +0000
tree a93e6b99878cd2f95e1c9d83dff1eba781cf18e2
parent 8581877121f58435d683c2a39a73e72e5dcd558a

Datachannel: Use absl::optional for maxRetransmits and maxRetransmitTime.

These parameters are nullable in the JS API.
This allows cleaner handling of "unset" vs "set" in Chrome.

Backwards compatibility note: Behavior should not change, even for users
who set the values explicitly to -1 in the DataChannelInit struct.
Those who try to read back the value will get a compile-time error.

Bug: chromium:854385
Change-Id: Ib488ca5f70bc24ba8b4a3f71b506434c4d2c60b2
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/131381
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27507}

pc/data_channel.h

diff --git a/pc/data_channel.h b/pc/data_channel.h
index 3e58c2b..e4166dd 100644
--- a/pc/data_channel.h
+++ b/pc/data_channel.h
@@ -57,18 +57,7 @@
   enum OpenHandshakeRole { kOpener, kAcker, kNone };
   // The default role is kOpener because the default |negotiated| is false.
   InternalDataChannelInit() : open_handshake_role(kOpener) {}
-  explicit InternalDataChannelInit(const DataChannelInit& base)
-      : DataChannelInit(base), open_handshake_role(kOpener) {
-    // If the channel is externally negotiated, do not send the OPEN message.
-    if (base.negotiated) {
-      open_handshake_role = kNone;
-    } else {
-      // Datachannel is externally negotiated. Ignore the id value.
-      // Specified in createDataChannel, WebRTC spec section 6.1 bullet 13.
-      id = -1;
-    }
-  }
-
+  explicit InternalDataChannelInit(const DataChannelInit& base);
   OpenHandshakeRole open_handshake_role;
 };
 
@@ -135,10 +124,21 @@
   virtual std::string label() const { return label_; }
   virtual bool reliable() const;
   virtual bool ordered() const { return config_.ordered; }
+  // Backwards compatible accessors
   virtual uint16_t maxRetransmitTime() const {
+    return config_.maxRetransmitTime ? *config_.maxRetransmitTime
+                                     : static_cast<uint16_t>(-1);
+  }
+  virtual uint16_t maxRetransmits() const {
+    return config_.maxRetransmits ? *config_.maxRetransmits
+                                  : static_cast<uint16_t>(-1);
+  }
+  virtual absl::optional<int> maxPacketLifeTime() const {
     return config_.maxRetransmitTime;
   }
-  virtual uint16_t maxRetransmits() const { return config_.maxRetransmits; }
+  virtual absl::optional<int> maxRetransmitsOpt() const {
+    return config_.maxRetransmits;
+  }
   virtual std::string protocol() const { return config_.protocol; }
   virtual bool negotiated() const { return config_.negotiated; }
   virtual int id() const { return config_.id; }
@@ -307,6 +307,8 @@
 PROXY_CONSTMETHOD0(bool, ordered)
 PROXY_CONSTMETHOD0(uint16_t, maxRetransmitTime)
 PROXY_CONSTMETHOD0(uint16_t, maxRetransmits)
+PROXY_CONSTMETHOD0(absl::optional<int>, maxRetransmitsOpt)
+PROXY_CONSTMETHOD0(absl::optional<int>, maxPacketLifeTime)
 PROXY_CONSTMETHOD0(std::string, protocol)
 PROXY_CONSTMETHOD0(bool, negotiated)
 PROXY_CONSTMETHOD0(int, id)