From 88ea6adb94c6a1b6f3d91b39419fdc87b9be6847 Mon Sep 17 00:00:00 2001
From: Paul-Louis Ageneau <paul-louis@ageneau.org>
Date: Tue, 30 Jul 2024 14:29:39 +0200
Subject: [PATCH] Add rtcIsNegotiationNeeded() to C API

---
 DOC.md                           | 12 ++++++++++++
 include/rtc/rtc.h                |  2 ++
 pages/content/pages/reference.md | 12 ++++++++++++
 src/capi.cpp                     |  5 +++++
 4 files changed, 31 insertions(+)

diff --git a/DOC.md b/DOC.md
index 50ad1758b..ca6d27cca 100644
--- a/DOC.md
+++ b/DOC.md
@@ -371,6 +371,18 @@ Return value: the maximun length of strings copied in buffers (including the ter
 
 If `local`, `remote`, or both, are `NULL`, the corresponding candidate is not copied, but the maximum length is still returned.
 
+#### rtcIsNegotiationNeeded
+```
+bool rtcIsNegotiationNeeded(int pc);
+```
+
+Return true if negotiation needs to be started or restarted, for instance to signal new tracks. If so, the user may call `rtcSetLocalDescription()` to start it.
+
+Arguments:
+- `pc`: the Peer Connection identifier
+
+Return value: true if negotiation is needed
+
 #### rtcGetMaxDataChannelStream
 ```
 int rtcGetMaxDataChannelStream(int pc);
diff --git a/include/rtc/rtc.h b/include/rtc/rtc.h
index bc7aed65f..2fc70c90c 100644
--- a/include/rtc/rtc.h
+++ b/include/rtc/rtc.h
@@ -227,6 +227,8 @@ RTC_C_EXPORT int rtcGetRemoteAddress(int pc, char *buffer, int size);
 RTC_C_EXPORT int rtcGetSelectedCandidatePair(int pc, char *local, int localSize, char *remote,
                                              int remoteSize);
 
+RTC_C_EXPORT bool rtcIsNegotiationNeeded(int pc);
+
 RTC_C_EXPORT int rtcGetMaxDataChannelStream(int pc);
 RTC_C_EXPORT int rtcGetRemoteMaxMessageSize(int pc);
 
diff --git a/pages/content/pages/reference.md b/pages/content/pages/reference.md
index ea10e5c10..fd4049db2 100644
--- a/pages/content/pages/reference.md
+++ b/pages/content/pages/reference.md
@@ -374,6 +374,18 @@ Return value: the maximun length of strings copied in buffers (including the ter
 
 If `local`, `remote`, or both, are `NULL`, the corresponding candidate is not copied, but the maximum length is still returned.
 
+#### rtcIsNegotiationNeeded
+```
+bool rtcIsNegotiationNeeded(int pc);
+```
+
+Return true if negotiation needs to be started or restarted, for instance to signal new tracks. If so, the user may call `rtcSetLocalDescription()` to start it.
+
+Arguments:
+- `pc`: the Peer Connection identifier
+
+Return value: true if negotiation is needed
+
 #### rtcGetMaxDataChannelStream
 ```
 int rtcGetMaxDataChannelStream(int pc);
diff --git a/src/capi.cpp b/src/capi.cpp
index bf7bca3c0..ead5cedf3 100644
--- a/src/capi.cpp
+++ b/src/capi.cpp
@@ -674,6 +674,11 @@ int rtcGetSelectedCandidatePair(int pc, char *local, int localSize, char *remote
 	});
 }
 
+bool rtcIsNegotiationNeeded(int pc) {
+	return wrap([&] { return getPeerConnection(pc)->negotiationNeeded() ? 0 : 1; }) == 0 ? true
+	                                                                                     : false;
+}
+
 int rtcGetMaxDataChannelStream(int pc) {
 	return wrap([&] {
 		auto peerConnection = getPeerConnection(pc);