daemon-conf: Add conf file parsing

Support to parse configuration files. By default, the default conf file
is parsed ({sysconfdir}/pinos/pinos.conf), but that can be changed with
an environment variable (PINOS_CONFIG_FILE). The file can contain
commands and assignments (no assignment supported this far).

Support for command module-load is added.

pinos/server/command.h

@@ -0,0 +1,69 @@
+/* Pinos
+ * Copyright (C) 2016 Axis Communications <dev-gstreamer@axis.com>
+ * @author Linus Svensson <linus.svensson@axis.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __PINOS_COMMAND_H__
+#define __PINOS_COMMAND_H__
+
+#include <glib.h>
+
+G_BEGIN_DECLS
+
+#include <server/daemon.h>
+
+typedef struct _PinosCommand PinosCommand;
+
+GQuark pinos_command_error_quark (void);
+/**
+ * PINOS_COMMAND_ERROR:
+ *
+ * Pinos command error.
+ */
+#define PINOS_COMMAND_ERROR (pinos_command_error_quark ())
+
+/**
+ * PinosCommandError:
+ * @PINOS_COMMAND_ERROR_GENERIC: Generic command error.
+ * @PINOS_COMMAND_ERROR_NO_SUCH_COMMAND: No such command.
+ * @PINOS_COMMAND_ERROR_PARSE: Failed to parse command.
+ * @PINOS_COMMAND_ERROR_FAILED: Command failed to execute.
+ *
+ * Error codes for Pinos command.
+ */
+typedef enum
+{
+  PINOS_COMMAND_ERROR_GENERIC,
+  PINOS_COMMAND_ERROR_NO_SUCH_COMMAND,
+  PINOS_COMMAND_ERROR_PARSE,
+  PINOS_COMMAND_ERROR_FAILED,
+} PinosCommandError;
+
+void               pinos_command_free                 (PinosCommand *command);
+
+gboolean           pinos_command_parse                (PinosCommand **command,
+                                                       gchar         *line,
+                                                       GError       **err);
+gboolean           pinos_command_run                  (PinosCommand  *command,
+                                                       PinosDaemon   *daemon,
+                                                       GError       **err);
+const gchar *      pinos_command_get_name             (PinosCommand  *command);
+
+G_END_DECLS
+
+#endif /* __PINOS_COMMAND_H__ */