flow: Properly type callbacks to protocol specific handlers

The flow dispatches deferred and timer handling for flows centrally, but
needs to call into protocol specific code for the handling of individual
flows.  Currently this passes a general union flow *.  It makes more sense
to pass the specific relevant flow type structure.  That brings the check
on the flow type adjacent to casting to the union variant which it tags.

Arguably, this is a slight abstraction violation since it involves the
generic flow code using protocol specific types.  It's already calling into
protocol specific functions, so I don't think this really makes any
difference.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 2 insertions, 4 deletions

diff --git a/icmp.c b/icmp.c
index 1c5cf84..eb559c1 100644
--- a/icmp.c
+++ b/icmp.c
@@ -289,16 +289,14 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
 /**
  * icmp_ping_timer() - Handler for timed events related to a given flow
  * @c:		Execution context
- * @flow:	flow table entry to check for timeout
+ * @pingf:	Ping flow to check for timeout
  * @now:	Current timestamp
  *
  * Return: true if the flow is ready to free, false otherwise
  */
-bool icmp_ping_timer(const struct ctx *c, union flow *flow,
+bool icmp_ping_timer(const struct ctx *c, const struct icmp_ping_flow *pingf,
 		     const struct timespec *now)
 {
-	const struct icmp_ping_flow *pingf = &flow->ping;
-
 	if (now->tv_sec - pingf->ts <= ICMP_ECHO_TIMEOUT)
 		return false;