conf parsing: Fix memory leaks and clean up code a bit.

Charybdis currently leaks about 45-50k per configuration parse,
including every rehash. This change plugs these leaks by properly
iterating through all conf_parm_t structures to seek all strings that
should be freed and also by freeing the conf_parm_t structures
themselves.

These leaks have been present since the original rewrite of the
configuration parsing system in ircd-ratbox r11953.

Additionally, this change also cleans up and documents the parsing code
a bit.

include/newconf.h

@@ -25,19 +25,27 @@ struct TopConf
 };
 
 
-#define CF_QSTRING	0x01
+#define CF_QSTRING	0x01 /* quoted string */
 #define CF_INT		0x02
-#define CF_STRING	0x03
+#define CF_STRING	0x03 /* unquoted string */
 #define CF_TIME		0x04
 #define CF_YESNO	0x05
-#define CF_LIST		0x06
-#define CF_ONE		0x07
 
-#define CF_MTYPE	0xFF
+#define CF_MTYPE	0xFF /* mask for type */
 
-#define CF_FLIST	0x1000
+/* CF_FLIST is used to allow specifying that an option accepts a list of (type)
-#define CF_MFLAG	0xFF00
+ * values. conf_parm_t.type will never actually have another type & CF_FLIST;
+ * it's only used as a true flag in newconf.c (which only consumes conf_parm_t
+ * structures and doesn't create them itself).
+ */
+#define CF_FLIST	0x0100 /* flag for list */
+#define CF_MFLAG	0xFF00 /* mask for flags */
 
+/* conf_parm_t.type must be either one type OR one flag. this is pretty easy to
+ * enforce because lists always contain nested conf_parm_t structures whose
+ * .type is the real type, so it doesn't need to be stored in the top-level one
+ * anyway.
+ */
 typedef struct conf_parm_t_stru
 {
 	struct conf_parm_t_stru *next;
@@ -59,7 +67,7 @@ extern char *current_file;
 int read_config(char *);
 int conf_start_block(char *, char *);
 int conf_end_block(struct TopConf *);
-int conf_call_set(struct TopConf *, char *, conf_parm_t *, int);
+int conf_call_set(struct TopConf *, char *, conf_parm_t *);
 void conf_report_error(const char *, ...);
 void newconf_init(void);
 int add_conf_item(const char *topconf, const char *name, int type, void (*func) (void *));

src/ircd_parser.y

@@ -101,22 +101,22 @@ static int	conf_get_yesno_value(char *str)
 
 static void	free_cur_list(conf_parm_t* list)
 {
-	switch (list->type & CF_MTYPE)
+	if (list->type == CF_STRING || list->type == CF_QSTRING) {
-	{
-		case CF_STRING:
-		case CF_QSTRING:
 	        rb_free(list->v.string);
-			break;
+	} else if (list->type == CF_FLIST) {
-		case CF_LIST:
+		/* Even though CF_FLIST is a flag, comparing with == is valid
+		 * because conf_parm_t.type must be either a type or one flag.
+		 */
 		free_cur_list(list->v.list);
-			break;
-		default: break;
 	}
 
-	if (list->next)
+	if (list->next) {
 		free_cur_list(list->next);
 	}
 
+	rb_free(list);
+}
+
 
 conf_parm_t *	cur_list = NULL;
 
@@ -125,7 +125,7 @@ static void	add_cur_list_cpt(conf_parm_t *new)
 	if (cur_list == NULL)
 	{
 		cur_list = rb_malloc(sizeof(conf_parm_t));
-		cur_list->type |= CF_FLIST;
+		cur_list->type = CF_FLIST;
 		cur_list->v.list = new;
 	}
 	else
@@ -216,7 +216,7 @@ block_items: block_items block_item
 
 block_item:	string '=' itemlist ';'
 		{
-			conf_call_set(conf_cur_block, $1, cur_list, CF_LIST);
+			conf_call_set(conf_cur_block, $1, cur_list);
 			free_cur_list(cur_list);
 			cur_list = NULL;
 		}
@@ -233,8 +233,7 @@ single: oneitem
 	| oneitem TWODOTS oneitem
 	{
 		/* "1 .. 5" meaning 1,2,3,4,5 - only valid for integers */
-		if (($1->type & CF_MTYPE) != CF_INT ||
+		if ($1->type != CF_INT || $3->type != CF_INT)
-		    ($3->type & CF_MTYPE) != CF_INT)
 		{
 			conf_report_error("Both arguments in '..' notation must be integers.");
 			break;

src/newconf.c

@@ -65,7 +65,7 @@ static char *yy_privset_extends = NULL;
 static const char *
 conf_strtype(int type)
 {
-	switch (type & CF_MTYPE)
+	switch (CF_TYPE(type))
 	{
 	case CF_INT:
 		return "integer value";
@@ -424,7 +424,7 @@ set_modes_from_table(int *modes, const char *whatis, struct mode_table *tab, con
 		int dir = 1;
 		int mode;
 
-		if((args->type & CF_MTYPE) != CF_STRING)
+		if(CF_TYPE(args->type) != CF_STRING)
 		{
 			conf_report_error("Warning -- %s is not a string; ignoring.", whatis);
 			continue;
@@ -857,7 +857,7 @@ conf_set_listen_port_both(void *data, int ssl)
 	conf_parm_t *args = data;
 	for (; args; args = args->next)
 	{
-		if((args->type & CF_MTYPE) != CF_INT)
+		if(CF_TYPE(args->type) != CF_INT)
 		{
 			conf_report_error
 				("listener::port argument is not an integer " "-- ignoring.");
@@ -1179,7 +1179,7 @@ conf_set_shared_oper(void *data)
 
 	if(args->next != NULL)
 	{
-		if((args->type & CF_MTYPE) != CF_QSTRING)
+		if(CF_TYPE(args->type) != CF_QSTRING)
 		{
 			conf_report_error("Ignoring shared::oper -- server is not a qstring");
 			return;
@@ -1191,7 +1191,7 @@ conf_set_shared_oper(void *data)
 	else
 		yy_shared->server = rb_strdup("*");
 
-	if((args->type & CF_MTYPE) != CF_QSTRING)
+	if(CF_TYPE(args->type) != CF_QSTRING)
 	{
 		conf_report_error("Ignoring shared::oper -- oper is not a qstring");
 		return;
@@ -2037,7 +2037,7 @@ conf_set_generic_string(void *data, int len, void *location)
 }
 
 int
-conf_call_set(struct TopConf *tc, char *item, conf_parm_t * value, int type)
+conf_call_set(struct TopConf *tc, char *item, conf_parm_t * value)
 {
 	struct ConfEntry *cf;
 	conf_parm_t *cp;