udhcp: rename server/client_config.arp to server_mac and client_mac

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/networking/udhcp/clientpacket.c b/networking/udhcp/clientpacket.c
index 3f9522f..068f947 100644
--- a/networking/udhcp/clientpacket.c
+++ b/networking/udhcp/clientpacket.c
@@ -37,11 +37,11 @@
 }
 
 
-/* initialize a packet with the proper defaults */
+/* Initialize the packet with the proper defaults */
 static void init_packet(struct dhcpMessage *packet, char type)
 {
 	udhcp_init_header(packet, type);
-	memcpy(packet->chaddr, client_config.arp, 6);
+	memcpy(packet->chaddr, client_config.client_mac, 6);
 	if (client_config.clientid)
 		add_option_string(packet->options, client_config.clientid);
 	if (client_config.hostname)
@@ -122,6 +122,7 @@
 }
 #endif
 
+
 /* Broadcast a DHCP discover packet to the network, with an optionally requested IP */
 int FAST_FUNC send_discover(uint32_t xid, uint32_t requested)
 {
@@ -143,7 +144,7 @@
 }
 
 
-/* Broadcasts a DHCP request message */
+/* Broadcast a DHCP request message */
 /* RFC 2131 3.1 paragraph 3:
  * "The client _broadcasts_ a DHCPREQUEST message..."
  */
diff --git a/networking/udhcp/common.h b/networking/udhcp/common.h
index de784ad..91e8ccc 100644
--- a/networking/udhcp/common.h
+++ b/networking/udhcp/common.h
@@ -88,7 +88,7 @@
 void udhcp_sp_setup(void) FAST_FUNC;
 int udhcp_sp_fd_set(fd_set *rfds, int extra_fd) FAST_FUNC;
 int udhcp_sp_read(const fd_set *rfds) FAST_FUNC;
-int udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *arp) FAST_FUNC;
+int udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *mac) FAST_FUNC;
 int udhcp_raw_socket(int ifindex) FAST_FUNC;
 int udhcp_listen_socket(/*uint32_t ip,*/ int port, const char *inf) FAST_FUNC;
 /* Returns 1 if no reply received */
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index ab34b04..44ff197 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -273,9 +273,14 @@
 		client_config.opt_mask[n >> 3] |= 1 << (n & 7);
 	}
 
-	if (udhcp_read_interface(client_config.interface, &client_config.ifindex,
-			   NULL, client_config.arp))
+	if (udhcp_read_interface(client_config.interface,
+			&client_config.ifindex,
+			NULL,
+			client_config.client_mac)
+	) {
 		return 1;
+	}
+
 #if !BB_MMU
 	/* on NOMMU reexec (i.e., background) early */
 	if (!(opt & OPT_f)) {
@@ -303,7 +308,7 @@
 	if (!client_config.clientid && !(opt & OPT_C)) {
 		client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7);
 		client_config.clientid[OPT_DATA] = 1;
-		memcpy(client_config.clientid + OPT_DATA+1, client_config.arp, 6);
+		memcpy(client_config.clientid + OPT_DATA+1, client_config.client_mac, 6);
 	}
 
 	if (!client_config.vendorclass)
@@ -490,7 +495,7 @@
 			}
 
 			/* Ignore packets that aren't for us */
-			if (memcmp(packet.chaddr, client_config.arp, 6)) {
+			if (memcmp(packet.chaddr, client_config.client_mac, 6)) {
 				DEBUG("Packet does not have our chaddr - ignoring");
 				continue;
 			}
@@ -555,7 +560,7 @@
 						if (!arpping(packet.yiaddr,
 								NULL,
 								(uint32_t) 0,
-								client_config.arp,
+								client_config.client_mac,
 								client_config.interface)
 						) {
 							bb_info_msg("offered address is in use "
diff --git a/networking/udhcp/dhcpc.h b/networking/udhcp/dhcpc.h
index 361624f..861e134 100644
--- a/networking/udhcp/dhcpc.h
+++ b/networking/udhcp/dhcpc.h
@@ -6,7 +6,7 @@
 PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
 
 struct client_config_t {
-	uint8_t arp[6];                 /* Our arp address */
+	uint8_t client_mac[6];          /* Our arp address */
 	/* TODO: combine flag fields into single "unsigned opt" */
 	/* (can be set directly to the result of getopt32) */
 	char no_default_options;        /* Do not include default optins in request */
diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index 5993042..c74a11b 100644
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -93,8 +93,11 @@
 	leases = xzalloc(server_config.max_leases * sizeof(*leases));
 	read_leases(server_config.lease_file);
 
-	if (udhcp_read_interface(server_config.interface, &server_config.ifindex,
-			   &server_config.server_nip, server_config.arp)) {
+	if (udhcp_read_interface(server_config.interface,
+			&server_config.ifindex,
+			&server_config.server_nip,
+			server_config.server_mac)
+	) {
 		retval = 1;
 		goto ret;
 	}
diff --git a/networking/udhcp/dhcpd.h b/networking/udhcp/dhcpd.h
index 4774fd1..b233962 100644
--- a/networking/udhcp/dhcpd.h
+++ b/networking/udhcp/dhcpd.h
@@ -28,17 +28,23 @@
 };
 
 struct server_config_t {
-	uint32_t server_nip;            /* Our IP, in network order */
+	char *interface;                /* interface to use */
+//TODO: ifindex, server_nip, server_mac
+// are obtained from interface name.
+// Instead of querying them *once*, create update_server_network_data_cache()
+// and call it before any usage of these fields.
+// update_server_network_data_cache() must re-query data
+// if more than N seconds have passed after last use.
+	int ifindex;
+	uint32_t server_nip;
 #if ENABLE_FEATURE_UDHCP_PORT
 	uint16_t port;
 #endif
+	uint8_t server_mac[6];          /* our MAC address (used only for ARP probing) */
+	struct option_set *options;     /* list of DHCP options loaded from the config file */
 	/* start,end are in host order: we need to compare start <= ip <= end */
-	uint32_t start_ip;              /* Start address of leases, in host order */
-	uint32_t end_ip;                /* End of leases, in host order */
-	struct option_set *options;     /* List of DHCP options loaded from the config file */
-	char *interface;                /* The name of the interface to use */
-	int ifindex;                    /* Index number of the interface to use */
-	uint8_t arp[6];                 /* Our arp address */
+	uint32_t start_ip;              /* start address of leases, in host order */
+	uint32_t end_ip;                /* end of leases, in host order */
 	uint32_t lease;	                /* lease time in seconds (host order) */
 	uint32_t max_leases;            /* maximum number of leases (including reserved address) */
 	uint32_t auto_time;             /* how long should udhcpd wait before writing a config file.
@@ -48,10 +54,10 @@
 	uint32_t conflict_time;         /* how long an arp conflict offender is leased for */
 	uint32_t offer_time;            /* how long an offered address is reserved */
 	uint32_t min_lease;             /* minimum lease time a client can request */
-	uint32_t siaddr_nip;                /* next server bootp option */
+	uint32_t siaddr_nip;            /* "next server" bootp option */
 	char *lease_file;
 	char *pidfile;
-	char *notify_file;              /* What to run whenever leases are written */
+	char *notify_file;              /* what to run whenever leases are written */
 	char *sname;                    /* bootp server name */
 	char *boot_file;                /* bootp boot file option */
 	struct static_lease *static_leases; /* List of ip/mac pairs to assign static leases */
diff --git a/networking/udhcp/leases.c b/networking/udhcp/leases.c
index c318856..291ae80 100644
--- a/networking/udhcp/leases.c
+++ b/networking/udhcp/leases.c
@@ -117,7 +117,7 @@
 }
 
 
-/* check is an IP is taken, if it is, add it to the lease table */
+/* Check if the IP is taken; if it is, add it to the lease table */
 static int nobody_responds_to_arp(uint32_t addr, const uint8_t *safe_mac)
 {
 	/* 16 zero bytes */
@@ -128,7 +128,8 @@
 	int r;
 
 	r = arpping(addr, safe_mac,
-			server_config.server_nip, server_config.arp,
+			server_config.server_nip,
+			server_config.server_mac,
 			server_config.interface);
 	if (r)
 		return r;
diff --git a/networking/udhcp/serverpacket.c b/networking/udhcp/serverpacket.c
index 5aa494b..d9c5ce3 100644
--- a/networking/udhcp/serverpacket.c
+++ b/networking/udhcp/serverpacket.c
@@ -37,7 +37,7 @@
 }
 
 
-/* send a packet to a specific arp address and ip address by creating our own ip packet */
+/* send a packet to a specific mac address and ip address by creating our own ip packet */
 static int send_packet_to_client(struct dhcpMessage *payload, int force_broadcast)
 {
 	const uint8_t *chaddr;
diff --git a/networking/udhcp/socket.c b/networking/udhcp/socket.c
index 449fcb7..de494ca 100644
--- a/networking/udhcp/socket.c
+++ b/networking/udhcp/socket.c
@@ -37,7 +37,7 @@
 #include "common.h"
 
 
-int FAST_FUNC udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *arp)
+int FAST_FUNC udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *mac)
 {
 	int fd;
 	struct ifreq ifr;
@@ -69,14 +69,14 @@
 		*ifindex = ifr.ifr_ifindex;
 	}
 
-	if (arp) {
+	if (mac) {
 		if (ioctl_or_warn(fd, SIOCGIFHWADDR, &ifr) != 0) {
 			close(fd);
 			return -1;
 		}
-		memcpy(arp, ifr.ifr_hwaddr.sa_data, 6);
+		memcpy(mac, ifr.ifr_hwaddr.sa_data, 6);
 		DEBUG("adapter hardware address %02x:%02x:%02x:%02x:%02x:%02x",
-			arp[0], arp[1], arp[2], arp[3], arp[4], arp[5]);
+			mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
 	}
 
 	close(fd);