Merge branch 'variadic-enumerators'

This adds several changes to enumerator_t and linked_list_t to improve
portability.  In particular to Apple's ARM64 iOS platform, whose calling
convention for variadic and regular functions are different.  This means
that assigning a non-variadic function to a variadic function pointer,
as we did with our enumerator_t::enumerate() implementations and several
callbacks, will result in crashes as the called function will access the
arguments differently than the caller provided them.

To avoid this issue the enumerator_t interface is now fully variadic.
A new mandatory method is added, venumerate(), that takes a va_list with
the arguments provided while enumerating.  enumerate() is replaced with
a generic implementation that prepares a va_list and calls the
enumerator's venumerate() implementation.  As this allows passing the
arguments of one enumerator to another it avoids the five pointer hack
used by enumerator_create_nested() and enumerator_create_cleaner().
To simplify the implementation of venumerate() a helper macro is provided
that assigns values from a given va_list to local variables.

The signature of the callback passed to enumerator_create_filter() has
also changed significantly.  It's now required to enumerate over the
original enumerator in the callback as this avoids the previous in/out
pointer hack. The arguments to the outer enumerator are provided in a
va_list.

Similar changes to avoid such five pointer hacks affect the signatures
of the callbacks for linked_list_t's invoke_function() and find_first()
methods.  For the latter the return type also changed from status_t to
bool, which is important as SUCCESS is defined as 0, so checks for ==
SUCCESS will now fail.

1 files changed, 15 insertions, 6 deletions

diff --git a/src/libcharon/plugins/kernel_netlink/kernel_netlink_ipsec.c b/src/libcharon/plugins/kernel_netlink/kernel_netlink_ipsec.c
index da05de304..c411b829d 100644
--- a/src/libcharon/plugins/kernel_netlink/kernel_netlink_ipsec.c
+++ b/src/libcharon/plugins/kernel_netlink/kernel_netlink_ipsec.c
@@ -542,10 +542,10 @@ static policy_sa_t *policy_sa_create(private_kernel_netlink_ipsec_t *this,
 /**
  * Destroy a policy_sa(_in)_t object
  */
-static void policy_sa_destroy(policy_sa_t *policy, policy_dir_t *dir,
+static void policy_sa_destroy(policy_sa_t *policy, policy_dir_t dir,
 							  private_kernel_netlink_ipsec_t *this)
 {
-	if (*dir == POLICY_OUT)
+	if (dir == POLICY_OUT)
 	{
 		policy_sa_out_t *out = (policy_sa_out_t*)policy;
 		out->src_ts->destroy(out->src_ts);
@@ -555,6 +555,16 @@ static void policy_sa_destroy(policy_sa_t *policy, policy_dir_t *dir,
 	free(policy);
 }
 
+CALLBACK(policy_sa_destroy_cb, void,
+	policy_sa_t *policy, va_list args)
+{
+	private_kernel_netlink_ipsec_t *this;
+	policy_dir_t dir;
+
+	VA_ARGS_VGET(args, dir, this);
+	policy_sa_destroy(policy, dir, this);
+}
+
 typedef struct policy_entry_t policy_entry_t;
 
 /**
@@ -599,9 +609,8 @@ static void policy_entry_destroy(private_kernel_netlink_ipsec_t *this,
 	}
 	if (policy->used_by)
 	{
-		policy->used_by->invoke_function(policy->used_by,
-										(linked_list_invoke_t)policy_sa_destroy,
-										 &policy->direction, this);
+		policy->used_by->invoke_function(policy->used_by, policy_sa_destroy_cb,
+										 policy->direction, this);
 		policy->used_by->destroy(policy->used_by);
 	}
 	free(policy);
@@ -2768,7 +2777,7 @@ METHOD(kernel_ipsec_t, del_policy, status_t,
 			ipsec_sa_equals(mapping->sa, &assigned_sa))
 		{
 			current->used_by->remove_at(current->used_by, enumerator);
-			policy_sa_destroy(mapping, &id->dir, this);
+			policy_sa_destroy(mapping, id->dir, this);
 			break;
 		}
 		if (is_installed)