Using @if with a variable like @if $VAR == "something" was always false.

Reported by BlackBishop.

This rename free_config_defines() to init_config_defines and calls it from
config_read_start() so caller doesn't have to think about it.

doc/RELEASE-NOTES.md

@@ -12,6 +12,8 @@ in progress and may not always be a stable version.
   the former.
 
 ### Fixes:
+* [Conditional config](https://www.unrealircd.org/docs/Defines_and_conditional_config):
+  using @if with a variable like `@if $VAR == "something"` always evaluated to false.
 * When booting for the first time (without any cached files) the IRCd
   downloads GeoIP.dat. If that fails, e.g. due to lack of internet connectivity,
   we now show a warning and continue booting instead of it being a hard error.

include/h.h

@@ -82,7 +82,7 @@ extern void preprocessor_cc_free_level(ConditionalConfig **cc_list, int level);
 extern void preprocessor_cc_free_list(ConditionalConfig *cc);
 extern void preprocessor_resolve_conditionals_ce(ConfigEntry **ce_list, PreprocessorPhase phase);
 extern void preprocessor_resolve_conditionals_all(PreprocessorPhase phase);
-extern void free_config_defines(void);
+extern void init_config_defines(void);
 extern void preprocessor_replace_defines(char **item, ConfigEntry *ce);
 
 /*

src/conf.c

@@ -2071,6 +2071,8 @@ int config_read_start(void)
 		return -1;
 	}
 
+	init_config_defines();
+
 	/* We set this to 1 because otherwise we may call rehash_internal()
 	 * already from config_read_file() which is too soon (race).
 	 */
@@ -2129,7 +2131,6 @@ int config_test(void)
 	config_setdefaultsettings(&tempiConf);
 	clicap_pre_rehash();
 	log_pre_rehash();
-	free_config_defines();
 
 	if (!config_loadmodules())
 	{

src/conf_preprocessor.c

@@ -365,6 +365,7 @@ int preprocessor_resolve_if(ConditionalConfig *cc, PreprocessorPhase phase)
 	if (cc->condition == IF_VALUE)
 	{
 		NameValuePrioList *d = find_config_define(cc->name);
+		config_status("Comparing @if %s shit %s vs %s", cc->name, d ? d->value : "<null>", cc->opt);
 		if (d && !strcasecmp(d->value, cc->opt))
 		{
 			result = 1;
@@ -417,8 +418,10 @@ void preprocessor_resolve_conditionals_all(PreprocessorPhase phase)
 		preprocessor_resolve_conditionals_ce(&cfptr->items, phase);
 }
 
-/** Frees the list of config_defines, so all @defines, and add the build-in ones */
-void free_config_defines(void)
+/** Frees the list of config_defines, so all @defines and then initialize the
+ * build-in ones.
+ */
+void init_config_defines(void)
 {
 	safe_free_nvplist(config_defines);
 	add_nvplist(&config_defines, 0, "UNREALIRCD_VERSION", VERSIONONLY);

src/ircd.c

@@ -824,7 +824,6 @@ int InitUnrealIRCd(int argc, char *argv[])
 	default_class->sendq = DEFAULT_RECVQ;
 	default_class->name = "default";
 	AddListItem(default_class, conf_class);
-	free_config_defines();
 	if (config_read_start() < 0)
 		exit(-1);
 	while (!is_config_read_finished())