From 622c2b2c3386dd8fad321fc3bbd4d019b99fbb71 Mon Sep 17 00:00:00 2001
From: Tobias Brunner <tobias@strongswan.org>
Date: Fri, 16 Oct 2015 12:31:38 +0200
Subject: [PATCH] peer-cfg: Add method to atomically replace child configs

---
 src/libcharon/config/peer_cfg.c | 114 +++++++++++++++++++++++++++++++-
 src/libcharon/config/peer_cfg.h |  16 ++++-
 2 files changed, 128 insertions(+), 2 deletions(-)

diff --git a/src/libcharon/config/peer_cfg.c b/src/libcharon/config/peer_cfg.c
index a0e336201..d28a79507 100644
--- a/src/libcharon/config/peer_cfg.c
+++ b/src/libcharon/config/peer_cfg.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2007-2008 Tobias Brunner
+ * Copyright (C) 2007-2015 Tobias Brunner
  * Copyright (C) 2005-2009 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -200,6 +200,117 @@ METHOD(peer_cfg_t, add_child_cfg, void,
 	this->mutex->unlock(this->mutex);
 }
 
+typedef struct {
+	enumerator_t public;
+	linked_list_t *removed;
+	linked_list_t *added;
+	enumerator_t *wrapped;
+	bool add;
+} child_cfgs_replace_enumerator_t;
+
+METHOD(enumerator_t, child_cfgs_replace_enumerate, bool,
+	child_cfgs_replace_enumerator_t *this, child_cfg_t **chd, bool *added)
+{
+	child_cfg_t *child_cfg;
+
+	if (!this->wrapped)
+	{
+		this->wrapped = this->removed->create_enumerator(this->removed);
+	}
+	while (TRUE)
+	{
+		if (this->wrapped->enumerate(this->wrapped, &child_cfg))
+		{
+			if (chd)
+			{
+				*chd = child_cfg;
+			}
+			if (added)
+			{
+				*added = this->add;
+			}
+			return TRUE;
+		}
+		if (this->add)
+		{
+			break;
+		}
+		this->wrapped = this->added->create_enumerator(this->added);
+		this->add = TRUE;
+	}
+	return FALSE;
+}
+
+METHOD(enumerator_t, child_cfgs_replace_enumerator_destroy, void,
+	child_cfgs_replace_enumerator_t *this)
+{
+	DESTROY_IF(this->wrapped);
+	this->removed->destroy_offset(this->removed, offsetof(child_cfg_t, destroy));
+	this->added->destroy_offset(this->added, offsetof(child_cfg_t, destroy));
+	free(this);
+}
+
+METHOD(peer_cfg_t, replace_child_cfgs, enumerator_t*,
+	private_peer_cfg_t *this, peer_cfg_t *other_pub)
+{
+	private_peer_cfg_t *other = (private_peer_cfg_t*)other_pub;
+	linked_list_t *removed, *added;
+	enumerator_t *mine, *others;
+	child_cfg_t *my_cfg, *other_cfg;
+	child_cfgs_replace_enumerator_t *enumerator;
+	bool found;
+
+	removed = linked_list_create();
+
+	other->mutex->lock(other->mutex);
+	added = linked_list_create_from_enumerator(
+					other->child_cfgs->create_enumerator(other->child_cfgs));
+	added->invoke_offset(added, offsetof(child_cfg_t, get_ref));
+	other->mutex->unlock(other->mutex);
+
+	this->mutex->lock(this->mutex);
+	others = added->create_enumerator(added);
+	mine = this->child_cfgs->create_enumerator(this->child_cfgs);
+	while (mine->enumerate(mine, &my_cfg))
+	{
+		found = FALSE;
+		while (others->enumerate(others, &other_cfg))
+		{
+			if (my_cfg->equals(my_cfg, other_cfg))
+			{
+				added->remove_at(added, others);
+				other_cfg->destroy(other_cfg);
+				found = TRUE;
+				break;
+			}
+		}
+		added->reset_enumerator(added, others);
+		if (!found)
+		{
+			this->child_cfgs->remove_at(this->child_cfgs, mine);
+			removed->insert_last(removed, my_cfg);
+		}
+	}
+	while (others->enumerate(others, &other_cfg))
+	{
+		this->child_cfgs->insert_last(this->child_cfgs,
+									  other_cfg->get_ref(other_cfg));
+	}
+	others->destroy(others);
+	mine->destroy(mine);
+	this->mutex->unlock(this->mutex);
+
+	INIT(enumerator,
+		.public = {
+			.enumerate = (void*)_child_cfgs_replace_enumerate,
+			.destroy = (void*)_child_cfgs_replace_enumerator_destroy,
+		},
+		.removed = removed,
+		.added = added,
+	);
+	return &enumerator->public;
+}
+
 /**
  * child_cfg enumerator
  */
@@ -645,6 +756,7 @@ peer_cfg_t *peer_cfg_create(char *name,
 			.get_ike_cfg = _get_ike_cfg,
 			.add_child_cfg = _add_child_cfg,
 			.remove_child_cfg = (void*)_remove_child_cfg,
+			.replace_child_cfgs = _replace_child_cfgs,
 			.create_child_cfg_enumerator = _create_child_cfg_enumerator,
 			.select_child_cfg = _select_child_cfg,
 			.get_cert_policy = _get_cert_policy,
diff --git a/src/libcharon/config/peer_cfg.h b/src/libcharon/config/peer_cfg.h
index 3e780394a..b612a2ef1 100644
--- a/src/libcharon/config/peer_cfg.h
+++ b/src/libcharon/config/peer_cfg.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2007-2008 Tobias Brunner
+ * Copyright (C) 2007-2015 Tobias Brunner
  * Copyright (C) 2005-2009 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -153,6 +153,20 @@ struct peer_cfg_t {
 	 */
 	void (*remove_child_cfg)(peer_cfg_t *this, enumerator_t *enumerator);
 
+	/**
+	 * Replace the CHILD configs with those in the given PEER config.
+	 *
+	 * Configs that are equal are not replaced.
+	 *
+	 * The enumerator enumerates the removed and added CHILD configs
+	 * (child_cfg_t*, bool), where the flag is FALSE for removed configs and
+	 * TRUE for added configs.
+	 *
+	 * @param other			other config to get CHILD configs from
+	 * @return				an enumerator over removed/added CHILD configs
+	 */
+	enumerator_t* (*replace_child_cfgs)(peer_cfg_t *this, peer_cfg_t *other);
+
 	/**
 	 * Create an enumerator for all attached CHILD configs.
 	 *