db/Configured: migrate from class Error to C++ exceptions

src/Main.cxx

@@ -183,14 +183,9 @@ glue_db_init_and_load(void)
 {
 	Error error;
 	instance->database =
-		CreateConfiguredDatabase(instance->event_loop, *instance,
-					 error);
-	if (instance->database == nullptr) {
-		if (error.IsDefined())
-			FatalError(error);
-		else
-			return true;
-	}
+		CreateConfiguredDatabase(instance->event_loop, *instance);
+	if (instance->database == nullptr)
+		return true;
 
 	if (instance->database->GetPlugin().flags & DatabasePlugin::FLAG_REQUIRE_STORAGE) {
 		InitStorage();

src/db/Configured.cxx

@@ -23,31 +23,26 @@
 #include "config/ConfigGlobal.hxx"
 #include "config/Param.hxx"
 #include "config/Block.hxx"
-#include "config/ConfigError.hxx"
 #include "fs/AllocatedPath.hxx"
 #include "fs/StandardDirectory.hxx"
-#include "util/Error.hxx"
+#include "util/RuntimeError.hxx"
 
 Database *
-CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener,
-			 Error &error)
+CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener)
 {
 	const auto *param = config_get_block(ConfigBlockOption::DATABASE);
 	const auto *path = config_get_param(ConfigOption::DB_FILE);
 
-	if (param != nullptr && path != nullptr) {
-		error.Format(config_domain,
-			     "Found both 'database' (line %d) and 'db_file' (line %d) setting",
-			     param->line, path->line);
-		return nullptr;
-	}
+	if (param != nullptr && path != nullptr)
+		throw FormatRuntimeError("Found both 'database' (line %d) and 'db_file' (line %d) setting",
+					 param->line, path->line);
 
 	if (param != nullptr)
-		return DatabaseGlobalInit(loop, listener, *param, error);
+		return DatabaseGlobalInit(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, error);
+		return DatabaseGlobalInit(loop, listener, block);
 	} else {
 		/* if there is no override, use the cache directory */
 
@@ -63,6 +58,6 @@ CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener,
 
 		ConfigBlock block;
 		block.AddBlockParam("path", db_file_utf8.c_str(), -1);
-		return DatabaseGlobalInit(loop, listener, block, error);
+		return DatabaseGlobalInit(loop, listener, block);
 	}
 }

src/db/Configured.hxx

@@ -25,15 +25,15 @@
 class EventLoop;
 class DatabaseListener;
 class Database;
-class Error;
 
 /**
  * Read database configuration settings and create a #Database
- * instance from it, but do not open it.  Returns nullptr on error or
- * if no database is configured (no #Error set in that case).
+ * instance from it, but do not open it.  Returns nullptr if no
+ * database is configured.
+ *
+ * Throws #std::runtime_error on error.
  */
 Database *
-CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener,
-			 Error &error);
+CreateConfiguredDatabase(EventLoop &loop, DatabaseListener &listener);
 
 #endif

src/db/DatabaseGlue.cxx

@@ -21,23 +21,21 @@
 #include "DatabaseGlue.hxx"
 #include "Registry.hxx"
 #include "DatabaseError.hxx"
-#include "util/Error.hxx"
+#include "util/RuntimeError.hxx"
 #include "config/Block.hxx"
 #include "DatabasePlugin.hxx"
 
 Database *
 DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
-		   const ConfigBlock &block, Error &error)
+		   const ConfigBlock &block)
 {
 	const char *plugin_name =
 		block.GetBlockValue("plugin", "simple");
 
 	const DatabasePlugin *plugin = GetDatabasePluginByName(plugin_name);
-	if (plugin == nullptr) {
-		error.Format(db_domain,
-			     "No such database plugin: %s", plugin_name);
-		return nullptr;
-	}
+	if (plugin == nullptr)
+		throw FormatRuntimeError("No such database plugin: %s",
+					 plugin_name);
 
 	return plugin->create(loop, listener, block);
 }

src/db/DatabaseGlue.hxx

@@ -26,15 +26,16 @@ struct ConfigBlock;
 class EventLoop;
 class DatabaseListener;
 class Database;
-class Error;
 
 /**
  * Initialize the database library.
  *
+ * Throws #std::runtime_error on error.
+ *
  * @param block the database configuration block
  */
 Database *
 DatabaseGlobalInit(EventLoop &loop, DatabaseListener &listener,
-		   const ConfigBlock &block, Error &error);
+		   const ConfigBlock &block);
 
 #endif