From 3dd04a6a94950c91b0895e6da9da5f84db1e7abc Mon Sep 17 00:00:00 2001
From: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Date: Fri, 13 Dec 2019 19:06:41 -0500
Subject: [PATCH] actions: implement is_equal
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Signed-off-by: Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
Change-Id: I9272253202cfd0d6b6fb165293a534a824fbe854
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---
 include/lttng/action/action-internal.h |  8 ++++++++
 src/common/actions/action.c            | 27 ++++++++++++++++++++++++++
 src/common/actions/notify.c            |  9 +++++++++
 3 files changed, 44 insertions(+)

diff --git a/include/lttng/action/action-internal.h b/include/lttng/action/action-internal.h
index d1868b06b..f747276c7 100644
--- a/include/lttng/action/action-internal.h
+++ b/include/lttng/action/action-internal.h
@@ -19,6 +19,8 @@ typedef bool (*action_validate_cb)(struct lttng_action *action);
 typedef void (*action_destroy_cb)(struct lttng_action *action);
 typedef int (*action_serialize_cb)(struct lttng_action *action,
 		struct lttng_dynamic_buffer *buf);
+typedef bool (*action_equal_cb)(const struct lttng_action *a,
+		const struct lttng_action *b);
 typedef ssize_t (*action_create_from_buffer_cb)(
 		const struct lttng_buffer_view *view,
 		struct lttng_action **action);
@@ -27,6 +29,7 @@ struct lttng_action {
 	enum lttng_action_type type;
 	action_validate_cb validate;
 	action_serialize_cb serialize;
+	action_equal_cb equal;
 	action_destroy_cb destroy;
 };
 
@@ -40,6 +43,7 @@ void lttng_action_init(struct lttng_action *action,
 		enum lttng_action_type type,
 		action_validate_cb validate,
 		action_serialize_cb serialize,
+		action_equal_cb equal,
 		action_destroy_cb destroy);
 
 LTTNG_HIDDEN
@@ -57,4 +61,8 @@ LTTNG_HIDDEN
 enum lttng_action_type lttng_action_get_type_const(
 		const struct lttng_action *action);
 
+LTTNG_HIDDEN
+bool lttng_action_is_equal(const struct lttng_action *a,
+		const struct lttng_action *b);
+
 #endif /* LTTNG_ACTION_INTERNAL_H */
diff --git a/src/common/actions/action.c b/src/common/actions/action.c
index f15163818..50e1b1d84 100644
--- a/src/common/actions/action.c
+++ b/src/common/actions/action.c
@@ -40,11 +40,13 @@ void lttng_action_init(
 		enum lttng_action_type type,
 		action_validate_cb validate,
 		action_serialize_cb serialize,
+		action_equal_cb equal,
 		action_destroy_cb destroy)
 {
 	action->type = type;
 	action->validate = validate;
 	action->serialize = serialize;
+	action->equal = equal;
 	action->destroy = destroy;
 }
 
@@ -155,3 +157,28 @@ ssize_t lttng_action_create_from_buffer(const struct lttng_buffer_view *view,
 end:
 	return consumed_len;
 }
+
+LTTNG_HIDDEN
+bool lttng_action_is_equal(const struct lttng_action *a,
+		const struct lttng_action *b)
+{
+	bool is_equal = false;
+
+	if (!a || !b) {
+		goto end;
+	}
+
+	if (a->type != b->type) {
+		goto end;
+	}
+
+	if (a == b) {
+		is_equal = true;
+		goto end;
+	}
+
+	assert(a->equal);
+	is_equal = a->equal(a, b);
+end:
+	return is_equal;
+}
diff --git a/src/common/actions/notify.c b/src/common/actions/notify.c
index ea68c75fd..d03bacb2e 100644
--- a/src/common/actions/notify.c
+++ b/src/common/actions/notify.c
@@ -23,6 +23,14 @@ int lttng_action_notify_serialize(struct lttng_action *action,
 	return 0;
 }
 
+static
+bool lttng_action_notify_is_equal(const struct lttng_action *a,
+		const struct lttng_action *b)
+{
+	/* There is no discriminant between notify actions. */
+	return true;
+}
+
 struct lttng_action *lttng_action_notify_create(void)
 {
 	struct lttng_action_notify *notify;
@@ -34,6 +42,7 @@ struct lttng_action *lttng_action_notify_create(void)
 
 	lttng_action_init(&notify->parent, LTTNG_ACTION_TYPE_NOTIFY, NULL,
 			lttng_action_notify_serialize,
+			lttng_action_notify_is_equal,
 			lttng_action_notify_destroy);
 end:
 	return &notify->parent;
-- 
2.34.1