From 8a02257d88276e2f2f10c407d2961995f74a192c Mon Sep 17 00:00:00 2001
From: William Lallemand <wlallemand@haproxy.com>
Date: Fri, 26 Oct 2018 14:47:35 +0200
Subject: [PATCH] MEDIUM: mworker: proxy for the master CLI

This patch implements a listen proxy within the master. It uses the
sockpair of all the workers as servers.

In the current state of the code, the proxy is only doing round robin on
the CLI of the workers. A CLI mode will be needed to know to which CLI
send the requests.
---
 include/proto/cli.h |  1 +
 src/cli.c           | 85 +++++++++++++++++++++++++++++++++++++++++++++
 src/haproxy.c       |  5 +++
 3 files changed, 91 insertions(+)

diff --git a/include/proto/cli.h b/include/proto/cli.h
index de1305b97..6d6ca35ff 100644
--- a/include/proto/cli.h
+++ b/include/proto/cli.h
@@ -28,6 +28,7 @@ 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_sockpair_new(struct mworker_proc *mworker_proc, int proc);
 
 #endif /* _PROTO_CLI_H */
diff --git a/src/cli.c b/src/cli.c
index 2c17c6b8f..161d1ebb0 100644
--- a/src/cli.c
+++ b/src/cli.c
@@ -93,6 +93,8 @@ static struct cli_kw_list cli_keywords = {
 
 extern const char *stat_status_codes[];
 
+static struct proxy *mworker_proxy; /* CLI proxy of the master */
+
 static char *cli_gen_usage_msg(struct appctx *appctx)
 {
 	struct cli_kw_list *kw_list;
@@ -1565,6 +1567,89 @@ static int cli_parse_simple(char **args, char *payload, struct appctx *appctx, v
 	return 1;
 }
 
+/*
+ * The mworker functions are used to initialize the CLI in the master process
+ */
+
+/*
+ * Create the mworker CLI proxy
+ */
+int mworker_cli_proxy_create()
+{
+	struct mworker_proc *child;
+
+	mworker_proxy = calloc(1, sizeof(*mworker_proxy));
+	if (!mworker_proxy)
+		return -1;
+
+	init_new_proxy(mworker_proxy);
+	mworker_proxy->next = proxies_list;
+	proxies_list = mworker_proxy;
+	mworker_proxy->id = strdup("MASTER");
+	mworker_proxy->mode = PR_MODE_TCP;
+	mworker_proxy->state = PR_STNEW;
+	mworker_proxy->last_change = now.tv_sec;
+	mworker_proxy->cap = PR_CAP_LISTEN; /* this is a listen section */
+	mworker_proxy->maxconn = 10;                 /* default to 10 concurrent connections */
+	mworker_proxy->timeout.client = 0; /* no timeout */
+	mworker_proxy->conf.file = strdup("MASTER");
+	mworker_proxy->conf.line = 0;
+	mworker_proxy->accept = frontend_accept;
+	mworker_proxy-> lbprm.algo = BE_LB_ALGO_NONE;
+
+	/* Does not init the default target the CLI applet, but must be done in
+	 * the request parsing code */
+	mworker_proxy->default_target = NULL;
+
+	/* the check_config_validity() will get an ID for the proxy */
+	mworker_proxy->uuid = -1;
+
+	proxy_store_name(mworker_proxy);
+
+	/* create all servers using the mworker_proc list */
+	list_for_each_entry(child, &proc_list, list) {
+		char *msg = NULL;
+		struct server *newsrv = NULL;
+		struct sockaddr_storage *sk;
+		int port1, port2, port;
+		struct protocol *proto;
+		char *errmsg;
+
+		newsrv = new_server(mworker_proxy);
+		if (!newsrv)
+			return -1;
+
+		/* we don't know the new pid yet */
+		if (child->pid == -1)
+			memprintf(&msg, "cur-%d", child->relative_pid);
+		else
+			memprintf(&msg, "old-%d", child->pid);
+
+		newsrv->next = mworker_proxy->srv;
+		mworker_proxy->srv = newsrv;
+		newsrv->conf.file = strdup(msg);
+		newsrv->id = strdup(msg);
+		newsrv->conf.line = 0;
+
+		memprintf(&msg, "sockpair@%d", child->ipc_fd[0]);
+		if ((sk = str2sa_range(msg, &port, &port1, &port2, &errmsg, NULL, NULL, 0)) == 0)
+			return -1;
+
+		proto = protocol_by_family(sk->ss_family);
+		if (!proto || !proto->connect) {
+			return -1;
+		}
+
+		/* no port specified */
+		newsrv->flags |= SRV_F_MAPPORTS;
+		newsrv->addr = *sk;
+		newsrv->iweight = 1;
+		newsrv->uweight = 1;
+		mworker_proxy->srv_act++;
+		srv_lb_commit_status(newsrv);
+	}
+	return 0;
+}
 
 /*
  * Create a new CLI socket using a socketpair for a worker process
diff --git a/src/haproxy.c b/src/haproxy.c
index e46690432..5affcd208 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -1722,6 +1722,11 @@ static void init(int argc, char **argv)
 			LIST_ADDQ(&proc_list, &tmproc->list);
 		}
 		mworker_env_to_proc_list(); /* get the info of the children in the env */
+
+		if (mworker_cli_proxy_create() < 0) {
+				ha_alert("Can't create the master's CLI.\n");
+				exit(EXIT_FAILURE);
+		}
 	}
 
 	pattern_finalize_config();