dhcp: get rid of last global data

function                                             old     new   delta
udhcpc_main                                         2680    2684      +4
state                                                  1       -      -1
listen_mode                                            1       -      -1
sockfd                                                 4       -      -4
------------------------------------------------------------------------------
(add/remove: 0/3 grow/shrink: 1/0 up/down: 4/-6)               Total: -2 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 40 insertions, 41 deletions

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 0e673ae7e..7b1b23706 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -984,13 +984,12 @@ static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd)
 
 /*** Main ***/
 
-static int sockfd = -1;
-
+/* Values for client_config.listen_mode */
 #define LISTEN_NONE   0
 #define LISTEN_KERNEL 1
 #define LISTEN_RAW    2
-static smallint listen_mode;
 
+/* Values for client_config.state */
 /* initial state: (re)start DHCP negotiation */
 #define INIT_SELECTING  0
 /* discover was sent, DHCPOFFER reply received */
@@ -1005,7 +1004,6 @@ static smallint listen_mode;
 #define RENEW_REQUESTED 5
 /* release, possibly manually requested (SIGUSR2) */
 #define RELEASED        6
-static smallint state;
 
 static int udhcp_raw_socket(int ifindex)
 {
@@ -1102,35 +1100,35 @@ static void change_listen_mode(int new_mode)
                         : "none"
         );
 
-        listen_mode = new_mode;
-        if (sockfd >= 0) {
-                close(sockfd);
-                sockfd = -1;
+        client_config.listen_mode = new_mode;
+        if (client_config.sockfd >= 0) {
+                close(client_config.sockfd);
+                client_config.sockfd = -1;
         }
         if (new_mode == LISTEN_KERNEL)
-                sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
+                client_config.sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
         else if (new_mode != LISTEN_NONE)
-                sockfd = udhcp_raw_socket(client_config.ifindex);
-        /* else LISTEN_NONE: sockfd stays closed */
+                client_config.sockfd = udhcp_raw_socket(client_config.ifindex);
+        /* else LISTEN_NONE: client_config.sockfd stays closed */
 }
 
 /* Called only on SIGUSR1 */
 static void perform_renew(void)
 {
         bb_info_msg("performing DHCP renew");
-        switch (state) {
+        switch (client_config.state) {
         case BOUND:
                 change_listen_mode(LISTEN_KERNEL);
         case RENEWING:
         case REBINDING:
-                state = RENEW_REQUESTED;
+                client_config.state = RENEW_REQUESTED;
                 break;
         case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
                 udhcp_run_script(NULL, "deconfig");
         case REQUESTING:
         case RELEASED:
                 change_listen_mode(LISTEN_RAW);
-                state = INIT_SELECTING;
+                client_config.state = INIT_SELECTING;
                 break;
         case INIT_SELECTING:
                 break;
@@ -1143,10 +1141,10 @@ static void perform_release(uint32_t server_addr, uint32_t requested_ip)
         struct in_addr temp_addr;
 
         /* send release packet */
-        if (state == BOUND
-         || state == RENEWING
-         || state == REBINDING
-         || state == RENEW_REQUESTED
+        if (client_config.state == BOUND
+         || client_config.state == RENEWING
+         || client_config.state == REBINDING
+         || client_config.state == RENEW_REQUESTED
         ) {
                 temp_addr.s_addr = server_addr;
                 strcpy(buffer, inet_ntoa(temp_addr));
@@ -1165,7 +1163,7 @@ static void perform_release(uint32_t server_addr, uint32_t requested_ip)
         udhcp_run_script(NULL, "deconfig");
 
         change_listen_mode(LISTEN_NONE);
-        state = RELEASED;
+        client_config.state = RELEASED;
 }
 
 static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
@@ -1270,6 +1268,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
         IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;)
         client_config.interface = "eth0";
         client_config.script = CONFIG_UDHCPC_DEFAULT_SCRIPT;
+        client_config.sockfd = -1;
         str_V = "udhcp "BB_VER;
 
         /* Parse command line */
@@ -1397,7 +1396,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
         /* We want random_xid to be random... */
         srand(monotonic_us());
 
-        state = INIT_SELECTING;
+        client_config.state = INIT_SELECTING;
         udhcp_run_script(NULL, "deconfig");
         change_listen_mode(LISTEN_RAW);
         packet_num = 0;
@@ -1415,16 +1414,16 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                 /* silence "uninitialized!" warning */
                 unsigned timestamp_before_wait = timestamp_before_wait;
 
-                //bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode);
+                //bb_error_msg("sockfd:%d, listen_mode:%d", client_config.sockfd, client_config.listen_mode);
 
                 /* Was opening raw or udp socket here
-                 * if (listen_mode != LISTEN_NONE && sockfd < 0),
+                 * if (client_config.listen_mode != LISTEN_NONE && client_config.sockfd < 0),
                  * but on fast network renew responses return faster
                  * than we open sockets. Thus this code is moved
                  * to change_listen_mode(). Thus we open listen socket
                  * BEFORE we send renew request (see "case BOUND:"). */
 
-                udhcp_sp_fd_set(pfds, sockfd);
+                udhcp_sp_fd_set(pfds, client_config.sockfd);
 
                 tv = timeout - already_waited_sec;
                 retval = 0;
@@ -1466,7 +1465,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                         /* We will restart the wait in any case */
                         already_waited_sec = 0;
 
-                        switch (state) {
+                        switch (client_config.state) {
                         case INIT_SELECTING:
                                 if (!discover_retries || packet_num < discover_retries) {
                                         if (packet_num == 0)
@@ -1515,11 +1514,11 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                  * were seen in the wild. Treat them similarly
                                  * to "no response to discover" case */
                                 change_listen_mode(LISTEN_RAW);
-                                state = INIT_SELECTING;
+                                client_config.state = INIT_SELECTING;
                                 goto leasefail;
                         case BOUND:
                                 /* 1/2 lease passed, enter renewing state */
-                                state = RENEWING;
+                                client_config.state = RENEWING;
                                 client_config.first_secs = 0; /* make secs field count from 0 */
                                 change_listen_mode(LISTEN_KERNEL);
                                 log1("entering renew state");
@@ -1556,7 +1555,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                 }
                                 /* Timed out or error, enter rebinding state */
                                 log1("entering rebinding state");
-                                state = REBINDING;
+                                client_config.state = REBINDING;
                                 /* fall right through */
                         case REBINDING:
                                 /* Switch to bcast receive */
@@ -1572,7 +1571,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                 /* Timed out, enter init state */
                                 bb_info_msg("lease lost, entering init state");
                                 udhcp_run_script(NULL, "deconfig");
-                                state = INIT_SELECTING;
+                                client_config.state = INIT_SELECTING;
                                 client_config.first_secs = 0; /* make secs field count from 0 */
                                 /*timeout = 0; - already is */
                                 packet_num = 0;
@@ -1592,7 +1591,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                         client_config.first_secs = 0; /* make secs field count from 0 */
                         already_waited_sec = 0;
                         perform_renew();
-                        if (state == RENEW_REQUESTED) {
+                        if (client_config.state == RENEW_REQUESTED) {
                                 /* We might be either on the same network
                                  * (in which case renew might work),
                                  * or we might be on a completely different one
@@ -1627,15 +1626,15 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                         int len;
 
                         /* A packet is ready, read it */
-                        if (listen_mode == LISTEN_KERNEL)
-                                len = udhcp_recv_kernel_packet(&packet, sockfd);
+                        if (client_config.listen_mode == LISTEN_KERNEL)
+                                len = udhcp_recv_kernel_packet(&packet, client_config.sockfd);
                         else
-                                len = udhcp_recv_raw_packet(&packet, sockfd);
+                                len = udhcp_recv_raw_packet(&packet, client_config.sockfd);
                         if (len == -1) {
                                 /* Error is severe, reopen socket */
                                 bb_error_msg("read error: "STRERROR_FMT", reopening socket" STRERROR_ERRNO);
                                 sleep(discover_timeout); /* 3 seconds by default */
-                                change_listen_mode(listen_mode); /* just close and reopen */
+                                change_listen_mode(client_config.listen_mode); /* just close and reopen */
                         }
                         /* If this packet will turn out to be unrelated/bogus,
                          * we will go back and wait for next one.
@@ -1666,7 +1665,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                         continue;
                 }
 
-                switch (state) {
+                switch (client_config.state) {
                 case INIT_SELECTING:
                         /* Must be a DHCPOFFER */
                         if (*message == DHCPOFFER) {
@@ -1708,7 +1707,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                 requested_ip = packet.yiaddr;
 
                                 /* enter requesting state */
-                                state = REQUESTING;
+                                client_config.state = REQUESTING;
                                 timeout = 0;
                                 packet_num = 0;
                                 already_waited_sec = 0;
@@ -1763,10 +1762,10 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                                         "(got ARP reply), declining");
                                                 send_decline(/*xid,*/ server_addr, packet.yiaddr);
 
-                                                if (state != REQUESTING)
+                                                if (client_config.state != REQUESTING)
                                                         udhcp_run_script(NULL, "deconfig");
                                                 change_listen_mode(LISTEN_RAW);
-                                                state = INIT_SELECTING;
+                                                client_config.state = INIT_SELECTING;
                                                 client_config.first_secs = 0; /* make secs field count from 0 */
                                                 requested_ip = 0;
                                                 timeout = tryagain_timeout;
@@ -1783,7 +1782,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                 requested_ip = packet.yiaddr;
 
                                 start = monotonic_sec();
-                                udhcp_run_script(&packet, state == REQUESTING ? "bound" : "renew");
+                                udhcp_run_script(&packet, client_config.state == REQUESTING ? "bound" : "renew");
                                 already_waited_sec = (unsigned)monotonic_sec() - start;
                                 timeout = lease_seconds / 2;
                                 if ((unsigned)timeout < already_waited_sec) {
@@ -1791,7 +1790,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                         timeout = already_waited_sec = 0;
                                 }
 
-                                state = BOUND;
+                                client_config.state = BOUND;
                                 change_listen_mode(LISTEN_NONE);
                                 if (opt & OPT_q) { /* quit after lease */
                                         goto ret0;
@@ -1833,11 +1832,11 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                                 /* return to init state */
                                 bb_info_msg("received %s", "DHCP NAK");
                                 udhcp_run_script(&packet, "nak");
-                                if (state != REQUESTING)
+                                if (client_config.state != REQUESTING)
                                         udhcp_run_script(NULL, "deconfig");
                                 change_listen_mode(LISTEN_RAW);
                                 sleep(3); /* avoid excessive network traffic */
-                                state = INIT_SELECTING;
+                                client_config.state = INIT_SELECTING;
                                 client_config.first_secs = 0; /* make secs field count from 0 */
                                 requested_ip = 0;
                                 timeout = 0;