networking/interface.c: was doing really strange caching of fd's
open for getting ifconfig data - ??! Simplified all that. -200 bytes.
This commit is contained in:
Denis Vlasenko
parent
54d14ca1a2
commit
1cc70225e7
@ -137,9 +137,6 @@ struct aftype {
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/* may modify src */
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int (*getmask) (char *src, struct sockaddr * mask, char *name);
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int fd;
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char *flag_file;
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};
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/* This structure defines hardware protocols and their handlers. */
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@ -530,11 +527,9 @@ int bbunpack(char **argv,
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int create_icmp_socket(void);
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int create_icmp6_socket(void);
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/* interface.c */
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struct aftype;
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struct hwtype;
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extern int interface_opt_a;
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int display_interfaces(char *ifname);
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struct aftype *get_aftype(const char *name);
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const struct aftype *get_aftype(const char *name);
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const struct hwtype *get_hwtype(const char *name);
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const struct hwtype *get_hwntype(int type);
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@ -36,7 +36,7 @@
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#include "inet_common.h"
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#include "busybox.h"
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#ifdef CONFIG_FEATURE_IPV6
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#if ENABLE_FEATURE_IPV6
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# define HAVE_AFINET6 1
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#else
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# undef HAVE_AFINET6
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@ -154,14 +154,13 @@ static int INET_input(/*int type,*/ const char *bufp, struct sockaddr *sap)
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*/
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}
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static struct aftype inet_aftype = {
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static const struct aftype inet_aftype = {
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.name = "inet",
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.title = "DARPA Internet",
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.af = AF_INET,
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.alen = 4,
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.sprint = INET_sprint,
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.input = INET_input,
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.fd = -1
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};
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#ifdef HAVE_AFINET6
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@ -208,14 +207,13 @@ static int INET6_input(/*int type,*/ const char *bufp, struct sockaddr *sap)
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*/
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}
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static struct aftype inet6_aftype = {
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static const struct aftype inet6_aftype = {
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.name = "inet6",
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.title = "IPv6",
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.af = AF_INET6,
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.alen = sizeof(struct in6_addr),
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.sprint = INET6_sprint,
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.input = INET6_input,
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.fd = -1
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};
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#endif /* HAVE_AFINET6 */
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@ -246,13 +244,16 @@ static const char *UNSPEC_sprint(struct sockaddr *sap, int numeric)
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return UNSPEC_print((unsigned char *)sap->sa_data);
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}
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static struct aftype unspec_aftype = {
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"unspec", "UNSPEC", AF_UNSPEC, 0,
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UNSPEC_print, UNSPEC_sprint, NULL, NULL,
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NULL,
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static const struct aftype unspec_aftype = {
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.name = "unspec",
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.title = "UNSPEC",
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.af = AF_UNSPEC,
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.alen = 0,
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.print = UNSPEC_print,
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.sprint = UNSPEC_sprint,
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};
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static struct aftype * const aftypes[] = {
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static const struct aftype *const aftypes[] = {
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&inet_aftype,
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#ifdef HAVE_AFINET6
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&inet6_aftype,
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@ -262,9 +263,9 @@ static struct aftype * const aftypes[] = {
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};
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/* Check our protocol family table for this family. */
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struct aftype *get_aftype(const char *name)
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const struct aftype *get_aftype(const char *name)
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{
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struct aftype * const *afp;
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const struct aftype *const *afp;
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afp = aftypes;
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while (*afp != NULL) {
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@ -276,9 +277,9 @@ struct aftype *get_aftype(const char *name)
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}
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/* Check our protocol family table for this family. */
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static struct aftype *get_afntype(int af)
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static const struct aftype *get_afntype(int af)
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{
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struct aftype * const *afp;
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const struct aftype *const *afp;
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afp = aftypes;
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while (*afp != NULL) {
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@ -289,20 +290,6 @@ static struct aftype *get_afntype(int af)
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return NULL;
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}
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/* Check our protocol family table for this family and return its socket */
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static int get_socket_for_af(int af)
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{
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struct aftype * const *afp;
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afp = aftypes;
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while (*afp != NULL) {
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if ((*afp)->af == af)
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return (*afp)->fd;
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afp++;
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}
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return -1;
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}
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struct user_net_device_stats {
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unsigned long long rx_packets; /* total packets received */
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unsigned long long tx_packets; /* total packets transmitted */
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@ -357,62 +344,8 @@ struct interface {
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int interface_opt_a; /* show all interfaces */
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static struct interface *int_list, *int_last;
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static int skfd = -1; /* generic raw socket desc. */
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static int sockets_open(int family)
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{
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struct aftype * const *aft;
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int sfd = -1;
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static int force = -1;
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if (force < 0) {
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force = 0;
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if (get_linux_version_code() < KERNEL_VERSION(2,1,0))
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force = 1;
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if (access("/proc/net", R_OK))
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force = 1;
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}
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for (aft = aftypes; *aft; aft++) {
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struct aftype *af = *aft;
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int type = SOCK_DGRAM;
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if (af->af == AF_UNSPEC)
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continue;
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if (family && family != af->af)
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continue;
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if (af->fd != -1) {
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sfd = af->fd;
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continue;
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}
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/* Check some /proc file first to not stress kmod */
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if (!family && !force && af->flag_file) {
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if (access(af->flag_file, R_OK))
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continue;
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}
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af->fd = socket(af->af, type, 0);
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if (af->fd >= 0)
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sfd = af->fd;
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}
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if (sfd < 0) {
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bb_error_msg("no usable address families found");
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}
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return sfd;
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}
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#ifdef CONFIG_FEATURE_CLEAN_UP
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static void sockets_close(void)
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{
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struct aftype * const *aft;
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for (aft = aftypes; *aft != NULL; aft++) {
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struct aftype *af = *aft;
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if( af->fd != -1 ) {
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close(af->fd);
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af->fd = -1;
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}
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}
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}
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#endif
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#if 0
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/* like strcmp(), but knows about numbers */
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except that the freshly added calls to xatoul() brf on ethernet aliases with
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@ -467,55 +400,6 @@ static struct interface *add_interface(char *name)
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return new;
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}
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static int if_readconf(void)
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{
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int numreqs = 30;
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struct ifconf ifc;
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struct ifreq *ifr;
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int n, err = -1;
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int skfd2;
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/* SIOCGIFCONF currently seems to only work properly on AF_INET sockets
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(as of 2.1.128) */
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skfd2 = get_socket_for_af(AF_INET);
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if (skfd2 < 0) {
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bb_perror_msg(("warning: no inet socket available"));
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/* Try to soldier on with whatever socket we can get hold of. */
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skfd2 = sockets_open(0);
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if (skfd2 < 0)
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return -1;
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}
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ifc.ifc_buf = NULL;
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for (;;) {
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ifc.ifc_len = sizeof(struct ifreq) * numreqs;
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ifc.ifc_buf = xrealloc(ifc.ifc_buf, ifc.ifc_len);
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if (ioctl(skfd2, SIOCGIFCONF, &ifc) < 0) {
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perror("SIOCGIFCONF");
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goto out;
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}
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if (ifc.ifc_len == sizeof(struct ifreq) * numreqs) {
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/* assume it overflowed and try again */
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numreqs += 10;
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continue;
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}
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break;
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}
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ifr = ifc.ifc_req;
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for (n = 0; n < ifc.ifc_len; n += sizeof(struct ifreq)) {
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add_interface(ifr->ifr_name);
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ifr++;
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}
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err = 0;
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out:
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free(ifc.ifc_buf);
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return err;
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}
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static char *get_name(char *name, char *p)
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{
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/* Extract <name> from nul-terminated p where p matches
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@ -550,7 +434,7 @@ static char *get_name(char *name, char *p)
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* old approach of multiple scanf occurrences with large numbers of
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* args. */
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/* static const char * const ss_fmt[] = { */
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/* static const char *const ss_fmt[] = { */
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/* "%lln%llu%lu%lu%lu%lu%ln%ln%lln%llu%lu%lu%lu%lu%lu", */
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/* "%llu%llu%lu%lu%lu%lu%ln%ln%llu%llu%lu%lu%lu%lu%lu", */
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/* "%llu%llu%lu%lu%lu%lu%lu%lu%llu%llu%lu%lu%lu%lu%lu%lu" */
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@ -558,13 +442,13 @@ static char *get_name(char *name, char *p)
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/* Lie about the size of the int pointed to for %n. */
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#if INT_MAX == LONG_MAX
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static const char * const ss_fmt[] = {
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static const char *const ss_fmt[] = {
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"%n%llu%u%u%u%u%n%n%n%llu%u%u%u%u%u",
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"%llu%llu%u%u%u%u%n%n%llu%llu%u%u%u%u%u",
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"%llu%llu%u%u%u%u%u%u%llu%llu%u%u%u%u%u%u"
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};
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#else
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static const char * const ss_fmt[] = {
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static const char *const ss_fmt[] = {
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"%n%llu%lu%lu%lu%lu%n%n%n%llu%lu%lu%lu%lu%lu",
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"%llu%llu%lu%lu%lu%lu%n%n%llu%llu%lu%lu%lu%lu%lu",
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"%llu%llu%lu%lu%lu%lu%lu%lu%llu%llu%lu%lu%lu%lu%lu%lu"
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@ -615,6 +499,54 @@ static inline int procnetdev_version(char *buf)
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return 0;
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}
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/* Used only if "/proc/net/dev" isn't available */
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static int if_readconf(void)
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{
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int numreqs = 30;
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struct ifconf ifc;
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struct ifreq *ifr;
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int n, err = -1;
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int skfd;
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ifc.ifc_buf = NULL;
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/* SIOCGIFCONF currently seems to only work properly on AF_INET sockets
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(as of 2.1.128) */
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skfd = socket(AF_INET, SOCK_DGRAM, 0);
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if (skfd < 0) {
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bb_perror_msg("error: no inet socket available");
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return -1;
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}
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for (;;) {
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ifc.ifc_len = sizeof(struct ifreq) * numreqs;
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ifc.ifc_buf = xrealloc(ifc.ifc_buf, ifc.ifc_len);
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if (ioctl(skfd, SIOCGIFCONF, &ifc) < 0) {
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perror("SIOCGIFCONF");
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goto out;
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}
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if (ifc.ifc_len == sizeof(struct ifreq) * numreqs) {
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/* assume it overflowed and try again */
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numreqs += 10;
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continue;
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}
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break;
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}
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ifr = ifc.ifc_req;
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for (n = 0; n < ifc.ifc_len; n += sizeof(struct ifreq)) {
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add_interface(ifr->ifr_name);
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ifr++;
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}
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err = 0;
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out:
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close(skfd);
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free(ifc.ifc_buf);
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return err;
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}
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static int if_readlist_proc(char *target)
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{
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static int proc_read;
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@ -660,11 +592,7 @@ static int if_readlist_proc(char *target)
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static int if_readlist(void)
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{
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int err = if_readlist_proc(NULL);
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if (!err)
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err = if_readconf();
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return err;
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return if_readlist_proc(NULL);
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}
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static int for_all_interfaces(int (*doit) (struct interface *, void *),
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@ -687,81 +615,74 @@ static int for_all_interfaces(int (*doit) (struct interface *, void *),
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static int if_fetch(struct interface *ife)
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{
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struct ifreq ifr;
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int fd;
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char *ifname = ife->name;
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int skfd;
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skfd = xsocket(AF_INET, SOCK_DGRAM, 0);
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(skfd, SIOCGIFFLAGS, &ifr) < 0)
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if (ioctl(skfd, SIOCGIFFLAGS, &ifr) < 0) {
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close(skfd);
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return -1;
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}
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ife->flags = ifr.ifr_flags;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(skfd, SIOCGIFHWADDR, &ifr) < 0)
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memset(ife->hwaddr, 0, 32);
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else
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memset(ife->hwaddr, 0, 32);
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if (ioctl(skfd, SIOCGIFHWADDR, &ifr) >= 0)
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memcpy(ife->hwaddr, ifr.ifr_hwaddr.sa_data, 8);
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ife->type = ifr.ifr_hwaddr.sa_family;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(skfd, SIOCGIFMETRIC, &ifr) < 0)
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ife->metric = 0;
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else
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ife->metric = 0;
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if (ioctl(skfd, SIOCGIFMETRIC, &ifr) >= 0)
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ife->metric = ifr.ifr_metric;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(skfd, SIOCGIFMTU, &ifr) < 0)
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ife->mtu = 0;
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else
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ife->mtu = 0;
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if (ioctl(skfd, SIOCGIFMTU, &ifr) >= 0)
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ife->mtu = ifr.ifr_mtu;
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memset(&ife->map, 0, sizeof(struct ifmap));
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#ifdef SIOCGIFMAP
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(skfd, SIOCGIFMAP, &ifr) == 0)
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ife->map = ifr.ifr_map;
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else
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#endif
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memset(&ife->map, 0, sizeof(struct ifmap));
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#ifdef HAVE_TXQUEUELEN
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(skfd, SIOCGIFTXQLEN, &ifr) < 0)
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ife->tx_queue_len = -1; /* unknown value */
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else
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ife->tx_queue_len = -1; /* unknown value */
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if (ioctl(skfd, SIOCGIFTXQLEN, &ifr) >= 0)
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ife->tx_queue_len = ifr.ifr_qlen;
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#else
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ife->tx_queue_len = -1; /* unknown value */
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#endif
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/* IPv4 address? */
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fd = get_socket_for_af(AF_INET);
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if (fd >= 0) {
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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ifr.ifr_addr.sa_family = AF_INET;
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memset(&ife->addr, 0, sizeof(struct sockaddr));
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if (ioctl(skfd, SIOCGIFADDR, &ifr) == 0) {
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ife->has_ip = 1;
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ife->addr = ifr.ifr_addr;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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ifr.ifr_addr.sa_family = AF_INET;
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if (ioctl(fd, SIOCGIFADDR, &ifr) == 0) {
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ife->has_ip = 1;
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ife->addr = ifr.ifr_addr;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(fd, SIOCGIFDSTADDR, &ifr) < 0)
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memset(&ife->dstaddr, 0, sizeof(struct sockaddr));
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else
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ife->dstaddr = ifr.ifr_dstaddr;
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memset(&ife->dstaddr, 0, sizeof(struct sockaddr));
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if (ioctl(skfd, SIOCGIFDSTADDR, &ifr) >= 0)
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ife->dstaddr = ifr.ifr_dstaddr;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(fd, SIOCGIFBRDADDR, &ifr) < 0)
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memset(&ife->broadaddr, 0, sizeof(struct sockaddr));
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else
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ife->broadaddr = ifr.ifr_broadaddr;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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memset(&ife->broadaddr, 0, sizeof(struct sockaddr));
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if (ioctl(skfd, SIOCGIFBRDADDR, &ifr) >= 0)
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ife->broadaddr = ifr.ifr_broadaddr;
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strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
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if (ioctl(fd, SIOCGIFNETMASK, &ifr) < 0)
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memset(&ife->netmask, 0, sizeof(struct sockaddr));
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else
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ife->netmask = ifr.ifr_netmask;
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} else
|
||||
memset(&ife->addr, 0, sizeof(struct sockaddr));
|
||||
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
|
||||
memset(&ife->netmask, 0, sizeof(struct sockaddr));
|
||||
if (ioctl(skfd, SIOCGIFNETMASK, &ifr) >= 0)
|
||||
ife->netmask = ifr.ifr_netmask;
|
||||
}
|
||||
|
||||
close(skfd);
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -887,7 +808,7 @@ static const struct hwtype ppp_hwtype = {
|
||||
.type = ARPHRD_PPP
|
||||
};
|
||||
|
||||
#ifdef CONFIG_FEATURE_IPV6
|
||||
#if ENABLE_FEATURE_IPV6
|
||||
static const struct hwtype sit_hwtype = {
|
||||
.name = "sit",
|
||||
.title = "IPv6-in-IPv4",
|
||||
@ -897,19 +818,19 @@ static const struct hwtype sit_hwtype = {
|
||||
} ;
|
||||
#endif
|
||||
|
||||
static const struct hwtype * const hwtypes[] = {
|
||||
static const struct hwtype *const hwtypes[] = {
|
||||
&loop_hwtype,
|
||||
ðer_hwtype,
|
||||
&ppp_hwtype,
|
||||
&unspec_hwtype,
|
||||
#ifdef CONFIG_FEATURE_IPV6
|
||||
#if ENABLE_FEATURE_IPV6
|
||||
&sit_hwtype,
|
||||
#endif
|
||||
NULL
|
||||
};
|
||||
|
||||
#ifdef IFF_PORTSEL
|
||||
static const char * const if_port_text[] = {
|
||||
static const char *const if_port_text[] = {
|
||||
/* Keep in step with <linux/netdevice.h> */
|
||||
"unknown",
|
||||
"10base2",
|
||||
@ -925,7 +846,7 @@ static const char * const if_port_text[] = {
|
||||
/* Check our hardware type table for this type. */
|
||||
const struct hwtype *get_hwtype(const char *name)
|
||||
{
|
||||
const struct hwtype * const *hwp;
|
||||
const struct hwtype *const *hwp;
|
||||
|
||||
hwp = hwtypes;
|
||||
while (*hwp != NULL) {
|
||||
@ -939,7 +860,7 @@ const struct hwtype *get_hwtype(const char *name)
|
||||
/* Check our hardware type table for this type. */
|
||||
const struct hwtype *get_hwntype(int type)
|
||||
{
|
||||
const struct hwtype * const *hwp;
|
||||
const struct hwtype *const *hwp;
|
||||
|
||||
hwp = hwtypes;
|
||||
while (*hwp != NULL) {
|
||||
@ -987,7 +908,7 @@ static void print_bytes_scaled(unsigned long long ull, const char *end)
|
||||
printf("X bytes:%llu (%llu.%u %sB)%s", ull, int_part, frac_part, ext, end);
|
||||
}
|
||||
|
||||
static const char * const ife_print_flags_strs[] = {
|
||||
static const char *const ife_print_flags_strs[] = {
|
||||
"UP ",
|
||||
"BROADCAST ",
|
||||
"DEBUG ",
|
||||
@ -1028,7 +949,7 @@ static const unsigned short ife_print_flags_mask[] = {
|
||||
|
||||
static void ife_print(struct interface *ptr)
|
||||
{
|
||||
struct aftype *ap;
|
||||
const struct aftype *ap;
|
||||
const struct hwtype *hw;
|
||||
int hf;
|
||||
int can_compress = 0;
|
||||
@ -1265,15 +1186,7 @@ int display_interfaces(char *ifname)
|
||||
{
|
||||
int status;
|
||||
|
||||
/* Create a channel to the NET kernel. */
|
||||
if ((skfd = sockets_open(0)) < 0) {
|
||||
bb_perror_msg_and_die("socket");
|
||||
}
|
||||
|
||||
/* Do we have to show the current setup? */
|
||||
status = if_print(ifname);
|
||||
#ifdef CONFIG_FEATURE_CLEAN_UP
|
||||
sockets_close();
|
||||
#endif
|
||||
exit(status < 0);
|
||||
|
||||
return (status < 0); /* status < 0 == 1 -- error */
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user