Log: new logging library API

Prepare to migrate away from GLib.  Currently, we're still using GLib
as a backend.

src/LogInit.hxx

@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_LOG_INIT_HXX
+#define MPD_LOG_INIT_HXX
+
+class Error;
+
+/**
+ * Configure a logging destination for daemon startup, before the
+ * configuration file is read.  This allows the daemon to use the
+ * logging library (and the command line verbose level) before it's
+ * daemonized.
+ *
+ * @param verbose true when the program is started with --verbose
+ */
+void
+log_early_init(bool verbose);
+
+bool
+log_init(bool verbose, bool use_stdout, Error &error);
+
+void
+log_deinit(void);
+
+void setup_log_output(bool use_stdout);
+
+int cycle_log_files(void);
+
+#endif /* LOG_H */