udhcpd: add -I LOCAL_ADDR option

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

diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index 9ad9595..3c2a9cb 100644 (file)
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -27,6 +27,7 @@
 //usage:       "DHCP server\n"
 //usage:     "\n       -f      Run in foreground"
 //usage:     "\n       -S      Log to syslog too"
+//usage:     "\n       -I ADDR Local address"
 //usage:       IF_FEATURE_UDHCP_PORT(
 //usage:     "\n       -P N    Use port N (default 67)"
 //usage:       )
@@ -302,6 +303,7 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv)
        unsigned num_ips;
        unsigned opt;
        struct option_set *option;
+       char *str_I = str_I;
        IF_FEATURE_UDHCP_PORT(char *str_P;)
 
 #if ENABLE_FEATURE_UDHCP_PORT
@@ -312,8 +314,10 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv)
 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
        opt_complementary = "vv";
 #endif
-       opt = getopt32(argv, "fSv"
-               IF_FEATURE_UDHCP_PORT("P:", &str_P)
+       opt = getopt32(argv, "fSI:v"
+               IF_FEATURE_UDHCP_PORT("P:")
+               , &str_I
+               IF_FEATURE_UDHCP_PORT(, &str_P)
                IF_UDHCP_VERBOSE(, &dhcp_verbose)
                );
        if (!(opt & 1)) { /* no -f */
@@ -326,8 +330,13 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv)
                openlog(applet_name, LOG_PID, LOG_DAEMON);
                logmode |= LOGMODE_SYSLOG;
        }
+       if (opt & 4) { /* -I */
+               len_and_sockaddr *lsa = xhost_and_af2sockaddr(str_I, 0, AF_INET);
+               server_config.server_nip = lsa->u.sin.sin_addr.s_addr;
+               free(lsa);
+       }
 #if ENABLE_FEATURE_UDHCP_PORT
-       if (opt & 8) { /* -P */
+       if (opt & 16) { /* -P */
                SERVER_PORT = xatou16(str_P);
                CLIENT_PORT = SERVER_PORT + 1;
        }
@@ -367,7 +376,7 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv)
 
        if (udhcp_read_interface(server_config.interface,
                        &server_config.ifindex,
-                       &server_config.server_nip,
+                       (server_config.server_nip == 0 ? &server_config.server_nip : NULL),
                        server_config.server_mac)
        ) {
                retval = 1;