From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Mon, 9 Nov 2026 09:10:34 +0000 (+0100)
Subject: MINOR: cli: store active CLI sessions in a global list
X-Git-Url: https://git.kaiwu.me/$%7BISSUES%7D/static/gitweb.js?a=commitdiff_plain;h=2367f7a0033d097e50d1a19dabe830f623b7cdb0;p=haproxy.git

MINOR: cli: store active CLI sessions in a global list

Implement a global list of the currently active CLI sessions. This is
sound as since only one CLI frontend exists per HAProxy instance (via
"stats socket" for a worker, or alternatively a master CLI via -S for a
master process).

Each session is appended in the CLI_ST_INIT state at the beginning of
cli_io_handler() and removed in cli_release_handler().

This will allow to implement new CLI commands which can interact with
other CLI sessions.
---

diff --git a/include/haproxy/applet-t.h b/include/haproxy/applet-t.h
index ff41fdf82..9a9268f98 100644
--- a/include/haproxy/applet-t.h
+++ b/include/haproxy/applet-t.h
@@ -136,6 +136,7 @@ struct appctx {
 		void (*io_release)(struct appctx *appctx); /* used within the cli_io_handler when st0 = CLI_ST_CALLBACK,
 							      if the command is terminated or the session released */
 		struct cli_kw *kw;      /* the keyword being processed */
+		struct mt_list sess_el; /* attach point in global <cli_session_list> */
 	} cli_ctx; /* context dedicated to the CLI applet */
 
 	struct buffer_wait buffer_wait; /* position in the list of objects waiting for a buffer */
diff --git a/src/cli.c b/src/cli.c
index e861c0303..edd20b3a6 100644
--- a/src/cli.c
+++ b/src/cli.c
@@ -96,6 +96,9 @@ struct show_env_ctx {
 	int show_one;    /* stop after showing the first one */
 };
 
+/* Currently active CLI sessions. */
+static struct mt_list cli_session_list = MT_LIST_HEAD_INIT(cli_session_list);
+
 /* CLI context for the "show fd" command */
 /* flags for show_fd_ctx->show_mask */
 #define CLI_SHOWFD_F_PI  0x00000001   /* pipes             */
@@ -1011,6 +1014,7 @@ int cli_init(struct appctx *appctx)
 	appctx->cli_ctx.cmdline = NULL;
 	appctx->cli_ctx.payload = BUF_NULL;
 	appctx->cli_ctx.max_payload_sz = global.tune.cli_max_payload_sz;
+	MT_LIST_APPEND(&cli_session_list, &appctx->cli_ctx.sess_el);
 
 	/* Wakeup the applet ASAP. */
         applet_need_more_data(appctx);
@@ -1275,6 +1279,11 @@ void cli_io_handler(struct appctx *appctx)
 {
 	appctx->st1 &= ~APPCTX_CLI_ST1_YIELD;
 
+	if (appctx->st0 == CLI_ST_INIT) {
+		/* Init global CLI sess list attach element. Ensure safe delete in release handler. */
+		MT_LIST_INIT(&appctx->cli_ctx.sess_el);
+	}
+
 	if (unlikely(applet_fl_test(appctx, APPCTX_FL_EOS|APPCTX_FL_ERROR))) {
 		appctx->st0 = CLI_ST_END;
 		goto out;
@@ -1523,6 +1532,10 @@ static void cli_release_handler(struct appctx *appctx)
 	else if (appctx->st0 == CLI_ST_PRINT_UMSG || appctx->st0 == CLI_ST_PRINT_UMSGERR) {
 		usermsgs_clr(NULL);
 	}
+
+	/* Removes from global list unless release is called early before first cli_io_handler() invocation. */
+	if (appctx->st0 > CLI_ST_INIT)
+		MT_LIST_DELETE(&appctx->cli_ctx.sess_el);
 }
 
 /* This function dumps all environment variables to the buffer. It returns 0