From be0d7ab72ab276f63eacc5c6600ea13e9dc0666c Mon Sep 17 00:00:00 2001
From: Peter Powell <petpow@saberuk.com>
Date: Thu, 26 Nov 2015 04:07:50 +0000
Subject: [PATCH] Fix CAP REQ to be atomic like the standard dictates.

Reported by @dequis on IRC.
---
 src/modules/m_cap.cpp | 16 ++++++++--------
 src/modules/m_cap.h   |  5 ++++-
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/src/modules/m_cap.cpp b/src/modules/m_cap.cpp
index e9f4dae90..37478243f 100644
--- a/src/modules/m_cap.cpp
+++ b/src/modules/m_cap.cpp
@@ -72,17 +72,17 @@ class CommandCAP : public Command
 			reghold.set(user, 1);
 			Data.Send();
 
-			if (Data.ack.size() > 0)
+			if (Data.wanted.empty())
 			{
-				std::string AckResult = irc::stringjoiner(" ", Data.ack, 0, Data.ack.size() - 1).GetJoined();
-				user->WriteServ("CAP %s ACK :%s", user->nick.c_str(), AckResult.c_str());
+				user->WriteServ("CAP %s ACK :%s", user->nick.c_str(), parameters[1].c_str());
+				return CMD_SUCCESS;
 			}
 
-			if (Data.wanted.size() > 0)
-			{
-				std::string NakResult = irc::stringjoiner(" ", Data.wanted, 0, Data.wanted.size() - 1).GetJoined();
-				user->WriteServ("CAP %s NAK :%s", user->nick.c_str(), NakResult.c_str());
-			}
+			// HACK: reset all of the caps which were enabled on this user because a cap request is atomic.
+			for (std::vector<std::pair<GenericCap*, int> >::iterator iter = Data.changed.begin(); iter != Data.changed.end(); ++iter)
+				iter->first->ext.set(user, iter->second);
+
+			user->WriteServ("CAP %s NAK :%s", user->nick.c_str(), parameters[1].c_str());
 		}
 		else if (subcommand == "END")
 		{
diff --git a/src/modules/m_cap.h b/src/modules/m_cap.h
index 409671f48..23cf8cf69 100644
--- a/src/modules/m_cap.h
+++ b/src/modules/m_cap.h
@@ -21,6 +21,8 @@
 #ifndef M_CAP_H
 #define M_CAP_H
 
+class GenericCap;
+
 class CapEvent : public Event
 {
  public:
@@ -35,6 +37,7 @@ class CapEvent : public Event
 	CapEventType type;
 	std::vector<std::string> wanted;
 	std::vector<std::string> ack;
+	std::vector<std::pair<GenericCap*, int> > changed; // HACK: clean this up before 2.2
 	User* user;
 	CapEvent(Module* sender, User* u, CapEventType capevtype) : Event(sender, "cap_request"), type(capevtype), user(u) {}
 };
@@ -67,7 +70,7 @@ class GenericCap
 					// we can handle this, so ACK it, and remove it from the wanted list
 					data->ack.push_back(*it);
 					data->wanted.erase(it);
-					ext.set(data->user, enablecap ? 1 : 0);
+					data->changed.push_back(std::make_pair(this, ext.set(data->user, enablecap ? 1 : 0)));
 					break;
 				}
 			}
-- 
2.39.2