db/DatabasePlugin: add #EventLoop parameter documentation

src/db/Configured.cxx

@@ -28,7 +28,8 @@
 #include "util/RuntimeError.hxx"
 
 Database *
-CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener)
+CreateConfiguredDatabase(EventLoop &main_event_loop,
+			 DatabaseListener &listener)
 {
 	const auto *param = config_get_block(ConfigBlockOption::DATABASE);
 	const auto *path = config_get_param(ConfigOption::DB_FILE);
@@ -38,11 +39,13 @@ CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener)
 					 param->line, path->line);
 
 	if (param != nullptr)
-		return DatabaseGlobalInit(loop, listener, *param);
+		return DatabaseGlobalInit(main_event_loop,
+					  listener, *param);
 	else if (path != nullptr) {
 		ConfigBlock block(path->line);
 		block.AddBlockParam("path", path->value.c_str(), path->line);
-		return DatabaseGlobalInit(loop, listener, block);
+		return DatabaseGlobalInit(main_event_loop,
+					  listener, block);
 	} else {
 		/* if there is no override, use the cache directory */
 
@@ -58,6 +61,7 @@ CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener)
 
 		ConfigBlock block;
 		block.AddBlockParam("path", db_file_utf8.c_str(), -1);
-		return DatabaseGlobalInit(loop, listener, block);
+		return DatabaseGlobalInit(main_event_loop,
+					  listener, block);
 	}
 }

src/db/Configured.hxx

@@ -34,6 +34,7 @@ class Database;
  * Throws #std::runtime_error on error.
  */
 Database *
-CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener);
+CreateConfiguredDatabase(EventLoop &main_event_loop,
+			 DatabaseListener &listener);
 
 #endif

src/db/DatabaseGlue.cxx

@@ -26,7 +26,8 @@
 #include "DatabasePlugin.hxx"
 
 Database *
-DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
+DatabaseGlobalInit(EventLoop &main_event_loop,
+		   DatabaseListener &listener,
 		   const ConfigBlock &block)
 {
 	const char *plugin_name =
@@ -38,7 +39,7 @@ DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
 					 plugin_name);
 
 	try {
-		return plugin->create(loop, listener, block);
+		return plugin->create(main_event_loop, listener, block);
 	} catch (...) {
 		std::throw_with_nested(FormatRuntimeError("Failed to initialize database plugin '%s'",
 							  plugin_name));

src/db/DatabaseGlue.hxx

@@ -35,7 +35,8 @@ class Database;
  * @param block the database configuration block
  */
 Database *
-DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
+DatabaseGlobalInit(EventLoop &main_event_loop,
+		   DatabaseListener &listener,
 		   const ConfigBlock &block);
 
 #endif

src/db/DatabasePlugin.hxx

@@ -46,8 +46,12 @@ struct DatabasePlugin {
 	 * Allocates and configures a database.
 	 *
 	 * Throws #std::runtime_error on error.
+	 *
+	 * @param main_event_loop the #EventLoop running in the same
+	 * thread which invokes #Database methods
 	 */
-	Database *(*create)(EventLoop &loop, DatabaseListener &listener,
+	Database *(*create)(EventLoop &main_event_loop,
+			    DatabaseListener &listener,
 			    const ConfigBlock &block);
 
 	constexpr bool RequireStorage() const {