Throw an exception when attempting to register an extension with a name that already exists

Previously this silently failed

2 files changed, 4 insertions, 3 deletions

diff --git a/src/base.cpp b/src/base.cpp
index bf74d9dc2..66a3cb140 100644
--- a/src/base.cpp
+++ b/src/base.cpp
@@ -132,9 +132,9 @@ void* ExtensionItem::unset_raw(Extensible* container)
 	return rv;
 }
 
-void ExtensionManager::Register(ExtensionItem* item)
+bool ExtensionManager::Register(ExtensionItem* item)
 {
-	types.insert(std::make_pair(item->name, item));
+	return types.insert(std::make_pair(item->name, item)).second;
 }
 
 void ExtensionManager::BeginUnregister(Module* module, std::vector<reference<ExtensionItem> >& list)
diff --git a/src/modules.cpp b/src/modules.cpp
index 1f135176c..4e4d20c70 100644
--- a/src/modules.cpp
+++ b/src/modules.cpp
@@ -448,7 +448,8 @@ void ModuleManager::AddService(ServiceProvider& item)
 				throw ModuleException("Mode "+std::string(item.name)+" already exists.");
 			return;
 		case SERVICE_METADATA:
-			ServerInstance->Extensions.Register(static_cast<ExtensionItem*>(&item));
+			if (!ServerInstance->Extensions.Register(static_cast<ExtensionItem*>(&item)))
+				throw ModuleException("Extension " + std::string(item.name) + " already exists.");
 			return;
 		case SERVICE_DATA:
 		case SERVICE_IOHOOK: