From 0de1293ff5001d2927ff0e1292d649b3db2fd63e Mon Sep 17 00:00:00 2001
From: Sylvain Rochet <gradator@gradator.net>
Date: Sat, 2 Jun 2012 13:03:43 +0200
Subject: [PATCH] clarifying what is actually the "datainput" entry in protent

---
 src/netif/ppp/pppd.h  |  3 +++
 src/netif/ppp/pppmy.c | 12 ++++++++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/netif/ppp/pppd.h b/src/netif/ppp/pppd.h
index 867f701b..df88d71f 100644
--- a/src/netif/ppp/pppd.h
+++ b/src/netif/ppp/pppd.h
@@ -428,6 +428,9 @@ struct protent {
 			  void (*printer) __P((void *, char *, ...)),
 			  void *arg));
 #endif /* PRINTPKT_SUPPORT */
+    /* FIXME: data input is only used by CCP, which is not supported at this time,
+     *        should we remove this entry and save some flash ?
+     */
     /* Process a received data packet */
     void (*datainput) __P((int unit, u_char *pkt, int len));
     bool enabled_flag;		/* 0 iff protocol is disabled */
diff --git a/src/netif/ppp/pppmy.c b/src/netif/ppp/pppmy.c
index e52c5e2d..9c00727c 100644
--- a/src/netif/ppp/pppmy.c
+++ b/src/netif/ppp/pppmy.c
@@ -277,13 +277,21 @@ static void ppp_input(void *arg) {
 		    (*protp->input)(pd, nb->payload, nb->len);
 		    goto out;
 		}
-#if 0 /* Unused ? */
+#if 0 /* UNUSED
+       *
+       * This is actually a (hacked?) way for the PPP kernel implementation to pass a
+       * data packet to the PPP daemon. The PPP daemon normally only do signaling
+       * (LCP, PAP, CHAP, IPCP, ...) and does not handle any data packet at all.
+       *
+       * This is only used by CCP, which we cannot support until we have a CCP data
+       * implementation.
+       */
 		if (protocol == (protp->protocol & ~0x8000) && protp->enabled_flag
 		    && protp->datainput != NULL) {
 		    (*protp->datainput)(pd, nb->payload, nb->len);
 		    goto out;
 		}
-#endif /* Unused */
+#endif /* UNUSED */
 	  }
 
 	  if (debug) {