commit 2b71810cb3a45c8a52537a72ff0198fa6ae298b7
author Willy Tarreau <w@1wt.eu> Wed Apr 21 07:32:39 2021 +0200
committer Willy Tarreau <w@1wt.eu> Wed Apr 21 09:20:17 2021 +0200
tree 79a09dc08dab755c19afb0369f0a8374c6da7aea
parent 3b9cdf1cb765d06ec9e0e6d099def245b330f12f

CLEANUP: lists/tree-wide: rename some list operations to avoid some confusion

The current "ADD" vs "ADDQ" is confusing because when thinking in terms
of appending at the end of a list, "ADD" naturally comes to mind, but
here it does the opposite, it inserts. Several times already it's been
incorrectly used where ADDQ was expected, the latest of which was a
fortunate accident explained in 6fa922562 ("CLEANUP: stream: explain
why we queue the stream at the head of the server list").

Let's use more explicit (but slightly longer) names now:

   LIST_ADD        ->       LIST_INSERT
   LIST_ADDQ       ->       LIST_APPEND
   LIST_ADDED      ->       LIST_INLIST
   LIST_DEL        ->       LIST_DELETE

The same is true for MT_LISTs, including their "TRY" variant.
LIST_DEL_INIT keeps its short name to encourage to use it instead of the
lazier LIST_DELETE which is often less safe.

The change is large (~674 non-comment entries) but is mechanical enough
to remain safe. No permutation was performed, so any out-of-tree code
can easily map older names to new ones.

The list doc was updated.

src/signal.c

diff --git a/src/signal.c b/src/signal.c
index 946157e..5ec7142 100644
--- a/src/signal.c
+++ b/src/signal.c
@@ -154,7 +154,7 @@
 		if (sig != SIGPROF)
 			signal(sig, SIG_DFL);
 		list_for_each_entry_safe(sh, shb, &signal_state[sig].handlers, list) {
-			LIST_DEL(&sh->list);
+			LIST_DELETE(&sh->list);
 			pool_free(pool_head_sig_handlers, sh);
 		}
 	}
@@ -188,7 +188,7 @@
 	sh->handler = fct;
 	sh->arg = arg;
 	sh->flags = SIG_F_TYPE_FCT;
-	LIST_ADDQ(&signal_state[sig].handlers, &sh->list);
+	LIST_APPEND(&signal_state[sig].handlers, &sh->list);
 	return sh;
 }
 
@@ -220,7 +220,7 @@
 	sh->handler = task;
 	sh->arg = reason & ~TASK_WOKEN_ANY;
 	sh->flags = SIG_F_TYPE_TASK;
-	LIST_ADDQ(&signal_state[sig].handlers, &sh->list);
+	LIST_APPEND(&signal_state[sig].handlers, &sh->list);
 	return sh;
 }
 
@@ -229,7 +229,7 @@
  */
 void signal_unregister_handler(struct sig_handler *handler)
 {
-	LIST_DEL(&handler->list);
+	LIST_DELETE(&handler->list);
 	pool_free(pool_head_sig_handlers, handler);
 }
 
@@ -251,7 +251,7 @@
 
 	list_for_each_entry_safe(sh, shb, &signal_state[sig].handlers, list) {
 		if (sh->handler == target) {
-			LIST_DEL(&sh->list);
+			LIST_DELETE(&sh->list);
 			pool_free(pool_head_sig_handlers, sh);
 			break;
 		}
@@ -271,7 +271,7 @@
 		return;
 
 	list_for_each_entry_safe(sh, shb, &signal_state[sig].handlers, list) {
-		LIST_DEL(&sh->list);
+		LIST_DELETE(&sh->list);
 		pool_free(pool_head_sig_handlers, sh);
 	}