From a9c807c1df378e59405d2101b07fcddce492ad43 Mon Sep 17 00:00:00 2001
From: "Nicholas J. Kain" <nicholas@kain.us>
Date: Mon, 4 Jul 2011 22:59:07 -0400
Subject: [PATCH] Rename DS_ARP_CHECK to the less confusing DS_COLLISION_CHECK.

Call arp_reopen_fd() if reading from the arp fd fails in any state other
than AS_COLLISION_CHECK or AS_GW_CHECK.
---
 ndhc/arp.c   | 8 +++-----
 ndhc/state.c | 6 +++---
 ndhc/state.h | 2 +-
 3 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/ndhc/arp.c b/ndhc/arp.c
index d0a559b..25f6eb9 100644
--- a/ndhc/arp.c
+++ b/ndhc/arp.c
@@ -1,5 +1,5 @@
 /* arp.c - arp ping checking
- * Time-stamp: <2011-07-04 22:51:19 njk>
+ * Time-stamp: <2011-07-04 22:57:35 njk>
  *
  * Copyright 2010-2011 Nicholas J. Kain <njkain@gmail.com>
  *
@@ -316,7 +316,7 @@ int arp_check(struct client_state_t *cs, struct dhcpmsg *packet)
     if (arp_ip_anon_ping(cs, arp_dhcp_packet.yiaddr) == -1)
         return -1;
     cs->arpPrevState = cs->dhcpState;
-    cs->dhcpState = DS_ARP_CHECK;
+    cs->dhcpState = DS_COLLISION_CHECK;
     cs->timeout = 2000;
     memcpy(&arp_dhcp_packet, packet, sizeof (struct dhcpmsg));
     arpreply_clear();
@@ -378,8 +378,6 @@ void arp_success(struct client_state_t *cs)
     cs->dhcpState = DS_BOUND;
     cs->init = 0;
     if (cs->arpPrevState == DS_RENEWING || cs->arpPrevState == DS_REBINDING) {
-        // XXX We need to be smarter about this and only issue an ifchange if
-        // the lease has actually changed.
         ifchange_bind(&arp_dhcp_packet);
         arp_switch_state(cs, AS_DEFENSE);
     } else {
@@ -475,7 +473,7 @@ void handle_arp_response(struct client_state_t *cs)
                 case AS_COLLISION_CHECK: arp_failed(cs); break;
                 case AS_GW_CHECK: arp_gw_failed(cs); break;
                 default:
-                    // XXX: close and re-open the FD in ALL cases
+                    arp_reopen_fd(cs);
                     break;
             }
         } else
diff --git a/ndhc/state.c b/ndhc/state.c
index 6770380..45bec46 100644
--- a/ndhc/state.c
+++ b/ndhc/state.c
@@ -42,7 +42,7 @@ dhcp_state_t dhcp_states[] = {
     { an_packet, renewing_timeout, frenew, nfrelease},       // RENEWING
     { an_packet, rebinding_timeout, frenew, nfrelease},      // REBINDING
     { 0, arp_gw_failed, frenew, anfrelease},                 // BOUND_GW_CHECK
-    { 0, arp_success, frenew, anfrelease},                   // ARP_CHECK
+    { 0, arp_success, frenew, anfrelease},                   // COLLISION_CHECK
     { 0, released_timeout, frenew, frelease},                // RELEASED
     { 0, 0, 0, 0},                                           // NUM_STATES
 };
@@ -173,7 +173,7 @@ static void an_packet(struct client_state_t *cs, struct dhcpmsg *packet,
         cs->renewTime = cs->lease >> 1;
         cs->rebindTime = (cs->lease * 0x7) >> 3; // * 0.875
 
-        // Can transition from DS_ARP_CHECK to DS_BOUND or DS_SELECTING.
+        // Can transition from DS_COLLISION_CHECK to DS_BOUND or DS_SELECTING.
         if (arp_check(cs, packet) == -1) {
             log_warning("arp_check failed to make arp socket, retrying lease");
             reinit_selecting(cs, 3000);
@@ -263,7 +263,7 @@ static void frenew(struct client_state_t *cs)
             set_listen_cooked(cs);
             send_renew(cs);
             break;
-        case DS_ARP_CHECK:
+        case DS_COLLISION_CHECK:
             // Cancel arp ping in progress and treat as previous state.
             if (arp_close_fd(cs))
                 cs->dhcpState = cs->arpPrevState;
diff --git a/ndhc/state.h b/ndhc/state.h
index 5bcf8f8..ecd65d2 100644
--- a/ndhc/state.h
+++ b/ndhc/state.h
@@ -11,7 +11,7 @@ typedef enum {
     DS_RENEWING,
     DS_REBINDING,
     DS_BOUND_GW_CHECK,
-    DS_ARP_CHECK,
+    DS_COLLISION_CHECK,
     DS_RELEASED,
     DS_NUM_STATES,
 } dhcp_states_t;