commit f3736ed3d8d4e6660ad8b82a8deff7aca8389e5c
author Harald Alvestrand <hta@webrtc.org> Mon Apr 08 11:09:30 2019
committer Commit Bot <commit-bot@chromium.org> Tue Apr 09 08:32:43 2019
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}

api/data_channel_interface.h

diff --git a/api/data_channel_interface.h b/api/data_channel_interface.h
index 1bd874e..f7032ec 100644
--- a/api/data_channel_interface.h
+++ b/api/data_channel_interface.h
@@ -18,6 +18,7 @@
 #include <stdint.h>
 #include <string>
 
+#include "absl/types/optional.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/copy_on_write_buffer.h"
 #include "rtc_base/ref_count.h"
@@ -35,15 +36,16 @@
   bool ordered = true;
 
   // The max period of time in milliseconds in which retransmissions will be
-  // sent. After this time, no more retransmissions will be sent. -1 if unset.
+  // sent. After this time, no more retransmissions will be sent.
   //
   // Cannot be set along with |maxRetransmits|.
-  int maxRetransmitTime = -1;
+  // This is called |maxPacketLifeTime| in the WebRTC JS API.
+  absl::optional<int> maxRetransmitTime;
 
-  // The max number of retransmissions. -1 if unset.
+  // The max number of retransmissions.
   //
   // Cannot be set along with |maxRetransmitTime|.
-  int maxRetransmits = -1;
+  absl::optional<int> maxRetransmits;
 
   // This is set by the application and opaque to the WebRTC implementation.
   std::string protocol;
@@ -137,8 +139,11 @@
   // implemented these APIs. They should all just return the values the
   // DataChannel was created with.
   virtual bool ordered() const;
+  // TODO(hta): Deprecate and remove the following two functions.
   virtual uint16_t maxRetransmitTime() const;
   virtual uint16_t maxRetransmits() const;
+  virtual absl::optional<int> maxRetransmitsOpt() const;
+  virtual absl::optional<int> maxPacketLifeTime() const;
   virtual std::string protocol() const;
   virtual bool negotiated() const;