MEDIUM: move listener->frontend to bind_conf->frontend

Historically, all listeners have a pointer to the frontend. But since
the introduction of SSL, we now have an intermediary layer called
bind_conf corresponding to a "bind" line. It makes no sense to have
the frontend on each listener given that it's the same for all
listeners belonging to a same bind_conf. Also certain parts like
SSL can only operate on bind_conf and need the frontend.

This patch fixes this by moving the frontend pointer from the listener
to the bind_conf. The extra indirection is quite cheap given and the
places were this is used are very scarce.

include/proto/listener.h

@@ -119,19 +119,18 @@ struct bind_kw *bind_find_kw(const char *kw);
 /* Dumps all registered "bind" keywords to the <out> string pointer. */
 void bind_dump_kws(char **out);
 
-/* allocate an bind_conf struct for a bind line, and chain it to list head <lh>.
+/* allocate an bind_conf struct for a bind line, and chain it to the frontend <fe>.
  * If <arg> is not NULL, it is duplicated into ->arg to store useful config
  * information for error reporting.
  */
-static inline struct bind_conf *bind_conf_alloc(struct list *lh, const char *file,
+static inline struct bind_conf *bind_conf_alloc(struct proxy *fe, const char *file,
                                  int line, const char *arg, struct xprt_ops *xprt)
 {
 	struct bind_conf *bind_conf = (void *)calloc(1, sizeof(struct bind_conf));
 
 	bind_conf->file = strdup(file);
 	bind_conf->line = line;
-	if (lh)
-		LIST_ADDQ(lh, &bind_conf->by_fe);
+	LIST_ADDQ(&fe->conf.bind, &bind_conf->by_fe);
 	if (arg)
 		bind_conf->arg = strdup(arg);
 
@@ -139,6 +138,7 @@ static inline struct bind_conf *bind_conf_alloc(struct list *lh, const char *fil
 	bind_conf->ux.gid = -1;
 	bind_conf->ux.mode = 0;
 	bind_conf->xprt = xprt;
+	bind_conf->frontend = fe;
 
 	LIST_INIT(&bind_conf->listeners);
 	return bind_conf;

include/types/listener.h

@@ -142,6 +142,7 @@ struct bind_conf {
 	X509     *ca_sign_cert;    /* CA certificate referenced by ca_file */
 	EVP_PKEY *ca_sign_pkey;    /* CA private key referenced by ca_key */
 #endif
+	struct proxy *frontend;    /* the frontend all these listeners belong to, or NULL */
 	struct xprt_ops *xprt;     /* transport-layer operations for all listeners */
 	int is_ssl;                /* SSL is required for these listeners */
 	int generate_certs;        /* 1 if generate-certificates option is set, else 0 */
@@ -181,7 +182,6 @@ struct listener {
 	struct list proto_list;         /* list in the protocol header */
 	int (*accept)(struct listener *l, int fd, struct sockaddr_storage *addr); /* upper layer's accept() */
 	struct task * (*handler)(struct task *t); /* protocol handler. It is a task */
-	struct proxy *frontend;		/* the frontend this listener belongs to, or NULL */
 	enum obj_type *default_target;  /* default target to use for accepted sessions or NULL */
 	struct list wait_queue;		/* link element to make the listener wait for something (LI_LIMITED)  */
 	unsigned int analysers;		/* bitmap of required protocol analysers */

src/cfgparse.c

@@ -297,7 +297,6 @@ int str2listener(char *str, struct proxy *curproxy, struct bind_conf *bind_conf,
 			l->obj_type = OBJ_TYPE_LISTENER;
 			LIST_ADDQ(&curproxy->conf.listeners, &l->by_fe);
 			LIST_ADDQ(&bind_conf->listeners, &l->by_bind);
-			l->frontend = curproxy;
 			l->bind_conf = bind_conf;
 
 			l->fd = fd;
@@ -2032,7 +2031,7 @@ int cfg_parse_peers(const char *file, int linenum, char **args, int kwm)
 				curpeers->peers_fe->conf.args.line = curpeers->peers_fe->conf.line = linenum;
 				peers_setup_frontend(curpeers->peers_fe);
 
-				bind_conf = bind_conf_alloc(&curpeers->peers_fe->conf.bind, file, linenum, args[2], &raw_sock);
+				bind_conf = bind_conf_alloc(curpeers->peers_fe, file, linenum, args[2], &raw_sock);
 
 				if (!str2listener(args[2], curpeers->peers_fe, bind_conf, file, linenum, &errmsg)) {
 					if (errmsg && *errmsg) {
@@ -2881,7 +2880,7 @@ int cfg_parse_listen(const char *file, int linenum, char **args, int kwm)
 			goto out;
 		}
 
-		bind_conf = bind_conf_alloc(&curproxy->conf.bind, file, linenum, args[1], &raw_sock);
+		bind_conf = bind_conf_alloc(curproxy, file, linenum, args[1], &raw_sock);
 
 		/* use default settings for unix sockets */
 		bind_conf->ux.uid  = global.unix_bind.ux.uid;

src/cli.c

@@ -215,7 +215,7 @@ static int stats_parse_global(char **args, int section_type, struct proxy *curpx
 			}
 		}
 
-		bind_conf = bind_conf_alloc(&global.stats_fe->conf.bind, file, line, args[2], &raw_sock);
+		bind_conf = bind_conf_alloc(global.stats_fe, file, line, args[2], &raw_sock);
 		bind_conf->level = ACCESS_LVL_OPER; /* default access level */
 
 		if (!str2listener(args[2], global.stats_fe, bind_conf, file, line, err)) {

src/hlua_fcn.c

@@ -470,12 +470,12 @@ int hlua_listener_get_stats(lua_State *L)
 
 	li = hlua_check_listener(L, 1);
 
-	if (!li->frontend) {
+	if (!li->bind_conf->frontend) {
 		lua_pushnil(L);
 		return 1;
 	}
 
-	stats_fill_li_stats(li->frontend, li, ST_SHLGNDS, stats, STATS_LEN);
+	stats_fill_li_stats(li->bind_conf->frontend, li, ST_SHLGNDS, stats, STATS_LEN);
 
 	lua_newtable(L);
 	for (i=0; i<ST_F_TOTAL_FIELDS; i++) {

src/listener.c

@@ -295,7 +295,7 @@ void delete_listener(struct listener *listener)
 void listener_accept(int fd)
 {
 	struct listener *l = fdtab[fd].owner;
-	struct proxy *p = l->frontend;
+	struct proxy *p = l->bind_conf->frontend;
 	int max_accept = l->maxaccept ? l->maxaccept : 1;
 	int expire;
 	int cfd;

src/peers.c

@@ -1753,7 +1753,7 @@ void peers_setup_frontend(struct proxy *fe)
 static struct appctx *peer_session_create(struct peers *peers, struct peer *peer)
 {
 	struct listener *l = LIST_NEXT(&peers->peers_fe->conf.listeners, struct listener *, by_fe);
-	struct proxy *p = l->frontend; /* attached frontend */
+	struct proxy *p = l->bind_conf->frontend; /* attached frontend */
 	struct appctx *appctx;
 	struct session *sess;
 	struct stream *s;

src/session.c

@@ -115,7 +115,7 @@ static void session_count_new(struct session *sess)
 int session_accept_fd(struct listener *l, int cfd, struct sockaddr_storage *addr)
 {
 	struct connection *cli_conn;
-	struct proxy *p = l->frontend;
+	struct proxy *p = l->bind_conf->frontend;
 	struct session *sess;
 	struct stream *strm;
 	struct task *t;