use the new parser by default

you can force the old parser with the command line flag
--force-old-config-parser-v4.4-only (which will be present in v4.4 only,
as the name suggests)

include/all.h

@@ -80,7 +80,7 @@
 #include "commands.h"
 #include "commands_parser.h"
 #include "config_directives.h"
-//#include "config_parser.h"
+#include "config_parser.h"
 #include "fake_outputs.h"
 #include "display_version.h"
 

include/commands_parser.h

@@ -27,6 +27,11 @@ struct CommandResult {
 
     /* Whether the command requires calling tree_render. */
     bool needs_tree_render;
+
+    /* The next state to transition to. Passed to the function so that we can
+     * determine the next state as a result of a function call, like
+     * cfg_criteria_pop_state() does. */
+    int next_state;
 };
 
 struct CommandResult *parse_command(const char *input);

include/config.h

@@ -24,6 +24,8 @@ extern char *current_configpath;
 extern Config config;
 extern SLIST_HEAD(modes_head, Mode) modes;
 extern TAILQ_HEAD(barconfig_head, Barconfig) barconfigs;
+/* defined in src/cfgparse.y */
+extern bool force_old_config_parser;
 
 /**
  * Used during the config file lexing/parsing to keep the state of the lexer