MEDIUM: mworker: create CLI listeners from argv[]

This patch introduces mworker_cli_proxy_new_listener() which allows the
creation of new listeners for the CLI proxy.

Using this function it is possible to create new listeners from the
program arguments with -Sa <unix_socket>. It is allowed to create
multiple listeners with several -Sa.

include/proto/cli.h

@@ -29,6 +29,7 @@ void cli_register_kw(struct cli_kw_list *kw_list);
 int cli_has_level(struct appctx *appctx, int level);
 
 int mworker_cli_proxy_create();
+int mworker_cli_proxy_new_listener(char *line);
 int mworker_cli_sockpair_new(struct mworker_proc *mworker_proc, int proc);
 
 #endif /* _PROTO_CLI_H */

src/cli.c

@@ -1651,6 +1651,104 @@ int mworker_cli_proxy_create()
 	return 0;
 }
 
+/*
+ * Create a new listener for the master CLI proxy
+ */
+int mworker_cli_proxy_new_listener(char *line)
+{
+	struct bind_conf *bind_conf;
+	struct listener *l;
+	char *err = NULL;
+	char *args[MAX_LINE_ARGS + 1];
+	int arg;
+	int cur_arg;
+
+	arg = 0;
+	args[0] = line;
+
+	/* args is a bind configuration with spaces replaced by commas */
+	while (*line && arg < MAX_LINE_ARGS) {
+
+		if (*line == ',') {
+			*line++ = '\0';
+			while (*line == ',')
+				line++;
+			args[++arg] = line;
+		}
+		line++;
+	}
+
+	args[++arg] = "\0";
+
+	bind_conf = bind_conf_alloc(mworker_proxy, "master-socket", 0, "", xprt_get(XPRT_RAW));
+
+	bind_conf->level &= ~ACCESS_LVL_MASK;
+	bind_conf->level |= ACCESS_LVL_ADMIN;
+
+	if (!str2listener(args[0], mworker_proxy, bind_conf, "master-socket", 0, &err)) {
+		ha_alert("Cannot create the listener of the master CLI\n");
+		return -1;
+	}
+
+	cur_arg = 1;
+
+	while (*args[cur_arg]) {
+			static int bind_dumped;
+			struct bind_kw *kw;
+
+			kw = bind_find_kw(args[cur_arg]);
+			if (kw) {
+				if (!kw->parse) {
+					memprintf(&err, "'%s %s' : '%s' option is not implemented in this version (check build options).",
+						  args[0], args[1], args[cur_arg]);
+					goto err;
+				}
+
+				if (kw->parse(args, cur_arg, global.stats_fe, bind_conf, &err) != 0) {
+					if (err)
+						memprintf(&err, "'%s %s' : '%s'", args[0], args[1], err);
+					else
+						memprintf(&err, "'%s %s' : error encountered while processing '%s'",
+						          args[0], args[1], args[cur_arg]);
+					goto err;
+				}
+
+				cur_arg += 1 + kw->skip;
+				continue;
+			}
+
+			if (!bind_dumped) {
+				bind_dump_kws(&err);
+				indent_msg(&err, 4);
+				bind_dumped = 1;
+			}
+
+			memprintf(&err, "'%s %s' : unknown keyword '%s'.%s%s",
+			          args[0], args[1], args[cur_arg],
+			          err ? " Registered keywords :" : "", err ? err : "");
+			goto err;
+	}
+
+
+	list_for_each_entry(l, &bind_conf->listeners, by_bind) {
+		l->maxconn = 10;
+		l->backlog = 10;
+		l->accept = session_accept_fd;
+		l->default_target = mworker_proxy->default_target;
+		/* don't make the peers subject to global limits and don't close it in the master */
+		l->options |= (LI_O_UNLIMITED|LI_O_MWORKER); /* we are keeping this FD in the master */
+		l->nice = -64;  /* we want to boost priority for local stats */
+		global.maxsock += l->maxconn;
+	}
+
+	return 0;
+
+err:
+	ha_alert("%s\n", err);
+	return -1;
+
+}
+
 /*
  * Create a new CLI socket using a socketpair for a worker process
  * <mworker_proc> is the process structure, and <proc> is the process number

src/haproxy.c

@@ -224,6 +224,8 @@ static void *run_thread_poll_loop(void *data);
 /* bitfield of a few warnings to emit just once (WARN_*) */
 unsigned int warned = 0;
 
+/* master CLI configuration (-S flag) */
+struct list mworker_cli_conf = LIST_HEAD_INIT(mworker_cli_conf);
 
 /* These are strings to be reported in the output of "haproxy -vv". They may
  * either be constants (in which case must_free must be zero) or dynamically
@@ -452,6 +454,7 @@ static void usage(char *name)
 		"        -dV disables SSL verify on servers side\n"
 		"        -sf/-st [pid ]* finishes/terminates old pids.\n"
 		"        -x <unix_socket> get listening sockets from a unix socket\n"
+		"        -S <unix_socket>[,<bind options>...] new stats socket for the master\n"
 		"\n",
 		name, DEFAULT_MAXCONN, cfg_maxpconn);
 	exit(1);
@@ -1563,6 +1566,22 @@ static void init(int argc, char **argv)
 				argv++;
 				argc--;
 			}
+			else if (*flag == 'S') {
+				struct wordlist *c;
+
+				if (argc <= 1 || argv[1][0] == '-') {
+					ha_alert("Socket and optional bind parameters expected with the -S flag\n");
+					usage(progname);
+				}
+				if ((c = malloc(sizeof(*c))) == NULL || (c->s = strdup(argv[1])) == NULL) {
+					ha_alert("Cannot allocate memory\n");
+					exit(EXIT_FAILURE);
+				}
+				LIST_ADD(&mworker_cli_conf, &c->list);
+
+				argv++;
+				argc--;
+			}
 			else if (*flag == 's' && (flag[1] == 'f' || flag[1] == 't')) {
 				/* list of pids to finish ('f') or terminate ('t') */
 
@@ -1701,6 +1720,7 @@ static void init(int argc, char **argv)
 
 	if (global.mode & MODE_MWORKER) {
 		int proc;
+		struct wordlist *it, *c;
 
 		for (proc = 0; proc < global.nbproc; proc++) {
 			struct mworker_proc *tmproc;
@@ -1727,6 +1747,18 @@ static void init(int argc, char **argv)
 				ha_alert("Can't create the master's CLI.\n");
 				exit(EXIT_FAILURE);
 		}
+
+		list_for_each_entry_safe(c, it, &mworker_cli_conf, list) {
+
+			if (mworker_cli_proxy_new_listener(c->s) < 0) {
+				ha_alert("Can't create the master's CLI.\n");
+				exit(EXIT_FAILURE);
+			}
+			LIST_DEL(&c->list);
+			free(c->s);
+			free(c);
+		}
+
 	}
 
 	pattern_finalize_config();