From: Willy Tarreau <w@1wt.eu>
Date: Tue, 19 May 2020 15:07:30 +0000 (+0200)
Subject: MINOR: applet: adopt the wait list entry from the CLI
X-Git-Tag: v2.2-dev8~32
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9597cbd17a984852395ce7337ca245b7f9c84ac1;p=thirdparty%2Fhaproxy.git

MINOR: applet: adopt the wait list entry from the CLI

A few fields, including a generic list entry, were added to the CLI context
by commit 300decc8d9 ("MINOR: cli: extend the CLI context with a list and
two offsets"). It turns out that the list entry (l0) is solely used to
consult rings and that the generic ring_write() code is restricted to a
consumer on the CLI due to this, which was not the initial intent. Let's
make it a general purpose wait_entry field that is properly initialized
during appctx_init(). This will allow any applet to wait on a ring, not
just the CLI.
---

diff --git a/include/proto/applet.h b/include/proto/applet.h
index 31b4d90252..14fbca2a12 100644
--- a/include/proto/applet.h
+++ b/include/proto/applet.h
@@ -53,6 +53,7 @@ static inline void appctx_init(struct appctx *appctx, unsigned long thread_mask)
 	appctx->call_rate.curr_ctr = 0;
 	appctx->call_rate.prev_ctr = 0;
 	appctx->state = 0;
+	LIST_INIT(&appctx->wait_entry);
 }
 
 /* Tries to allocate a new appctx and initialize its main fields. The appctx
diff --git a/include/types/applet.h b/include/types/applet.h
index b990726f7c..013c5023d1 100644
--- a/include/types/applet.h
+++ b/include/types/applet.h
@@ -73,6 +73,7 @@ struct appctx {
 	unsigned long thread_mask;      /* mask of thread IDs authorized to process the applet */
 	struct task *t;                  /* task associated to the applet */
 	struct freq_ctr call_rate;       /* appctx call rate */
+	struct list wait_entry;          /* entry in a list of waiters for an event (e.g. ring events) */
 
 	union {
 		struct {
@@ -105,7 +106,6 @@ struct appctx {
 			const char *msg;        /* pointer to a persistent message to be returned in CLI_ST_PRINT state */
 			int severity;           /* severity of the message to be returned according to (syslog) rfc5424 */
 			char *err;              /* pointer to a 'must free' message to be returned in CLI_ST_PRINT_FREE state */
-			struct list l0;         /* General purpose list element, pointers, offsets and integers for... */
 			void *p0, *p1, *p2;     /* ...registered commands, initialized to 0 by the CLI before first... */
 			size_t o0, o1;          /* ...invocation of the keyword parser, except for the list element which... */
 			int i0, i1;             /* ...is initialized with LIST_INIT(). */
diff --git a/src/cli.c b/src/cli.c
index af17811041..a083ae7f6a 100644
--- a/src/cli.c
+++ b/src/cli.c
@@ -500,7 +500,6 @@ static int cli_parse_request(struct appctx *appctx)
 
 	appctx->st2 = 0;
 	memset(&appctx->ctx.cli, 0, sizeof(appctx->ctx.cli));
-	LIST_INIT(&appctx->ctx.cli.l0);
 
 	p = appctx->chunk->area;
 	end = p + appctx->chunk->data;
diff --git a/src/ring.c b/src/ring.c
index ec0656fbcf..48003b38bc 100644
--- a/src/ring.c
+++ b/src/ring.c
@@ -191,7 +191,7 @@ ssize_t ring_write(struct ring *ring, size_t maxlen, const struct ist pfx[], siz
 	sent = lenlen + totlen + 1;
 
 	/* notify potential readers */
-	list_for_each_entry(appctx, &ring->waiters, ctx.cli.l0)
+	list_for_each_entry(appctx, &ring->waiters, wait_entry)
 		appctx_wakeup(appctx);
 
  done_buf:
@@ -249,7 +249,7 @@ int cli_io_handler_show_ring(struct appctx *appctx)
 		return 1;
 
 	HA_RWLOCK_WRLOCK(LOGSRV_LOCK, &ring->lock);
-	LIST_DEL_INIT(&appctx->ctx.cli.l0);
+	LIST_DEL_INIT(&appctx->wait_entry);
 	HA_RWLOCK_WRUNLOCK(LOGSRV_LOCK, &ring->lock);
 
 	HA_RWLOCK_RDLOCK(LOGSRV_LOCK, &ring->lock);
@@ -324,7 +324,7 @@ int cli_io_handler_show_ring(struct appctx *appctx)
 		if (!si_oc(si)->output && !(si_oc(si)->flags & CF_SHUTW)) {
 			/* let's be woken up once new data arrive */
 			HA_RWLOCK_WRLOCK(LOGSRV_LOCK, &ring->lock);
-			LIST_ADDQ(&ring->waiters, &appctx->ctx.cli.l0);
+			LIST_ADDQ(&ring->waiters, &appctx->wait_entry);
 			HA_RWLOCK_WRUNLOCK(LOGSRV_LOCK, &ring->lock);
 			si_rx_endp_done(si);
 			ret = 0;
@@ -349,7 +349,7 @@ void cli_io_release_show_ring(struct appctx *appctx)
 		/* reader was still attached */
 		ofs -= ring->ofs;
 		BUG_ON(ofs >= b_size(&ring->buf));
-		LIST_DEL_INIT(&appctx->ctx.cli.l0);
+		LIST_DEL_INIT(&appctx->wait_entry);
 		HA_ATOMIC_SUB(b_peek(&ring->buf, ofs), 1);
 	}
 	HA_ATOMIC_SUB(&ring->readers_count, 1);