getnameinfo.c

ソースコードを見る。

データ構造
struct	afd
struct	sockinet
関数
int	getnameinfo (struct sockaddr *sa, size_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags) const
変数
static struct afd	afdl []

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関数

int getnameinfo	(	struct sockaddr *	sa,
		size_t	salen,
		char *	host,
		size_t	hostlen,
		char *	serv,
		size_t	servlen,
		int	flags
	)			const

getnameinfo.c の 75 行で定義されています。

参照先 afd::a_addrlen・afd::a_af・afd::a_off・afd::a_socklen・afdl・freehostent()・inet_ntop()・snprintf().

参照元 client_addr()・lookup_name().

{
        extern int h_errno;
        struct afd *afd;
        struct servent *sp;
        struct hostent *hp;
        u_short port;
        int family, i;
        char *addr, *p;
        u_long v4a;
#ifdef INET6
        u_char pfx;
#endif
        int h_error;
        char numserv[512];
        char numaddr[512];

        if (sa == NULL)
                return ENI_NOSOCKET;

#ifdef HAVE_SOCKADDR_LEN
        if (sa->sa_len != salen) return ENI_SALEN;
#endif
        
        family = sa->sa_family;
        for (i = 0; afdl[i].a_af; i++)
                if (afdl[i].a_af == family) {
                        afd = &afdl[i];
                        goto found;
                }
        return ENI_FAMILY;
        
 found:
        if (salen != afd->a_socklen) return ENI_SALEN;
        
        port = ((struct sockinet *)sa)->si_port; /* network byte order */
        addr = (char *)sa + afd->a_off;

        if (serv == NULL || servlen == 0) {
                /* what we should do? */
        } else if (flags & NI_NUMERICSERV) {
                snprintf(numserv, sizeof(numserv), "%d", ntohs(port));
                if (strlen(numserv) > servlen)
                        return ENI_MEMORY;
                strcpy(serv, numserv);
        } else {
                sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp");
                if (sp) {
                        if (strlen(sp->s_name) > servlen)
                                return ENI_MEMORY;
                        strcpy(serv, sp->s_name);
                } else
                        return ENI_NOSERVNAME;
        }

        switch (sa->sa_family) {
        case AF_INET:
                v4a = ((struct sockaddr_in *)sa)->sin_addr.s_addr;
                if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
                        flags |= NI_NUMERICHOST;
                v4a >>= IN_CLASSA_NSHIFT;
                if (v4a == 0 || v4a == IN_LOOPBACKNET)
                        flags |= NI_NUMERICHOST;                        
                break;
#ifdef INET6
        case AF_INET6:
                pfx = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr[0];
                if (pfx == 0 || pfx == 0xfe || pfx == 0xff)
                        flags |= NI_NUMERICHOST;
                break;
#endif
        }
        if (host == NULL || hostlen == 0) {
                /* what should we do? */
        } else if (flags & NI_NUMERICHOST) {
                if (!inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)))
                        return ENI_SYSTEM;
                if (strlen(numaddr) > hostlen)
                        return ENI_MEMORY;
                strcpy(host, numaddr);
        } else {
#ifdef INET6
                hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
#else
                hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
                h_error = h_errno;
#endif

                if (hp) {
                        if (flags & NI_NOFQDN) {
                                p = strchr(hp->h_name, '.');
                                if (p) *p = '\0';
                        }
                        if (strlen(hp->h_name) > hostlen) {
#ifdef INET6
                                freehostent(hp);
#endif
                                return ENI_MEMORY;
                        }
                        strcpy(host, hp->h_name);
#ifdef INET6
                        freehostent(hp);
#endif
                } else {
                        if (flags & NI_NAMEREQD)
                                return ENI_NOHOSTNAME;
                        if (!inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)))
                                return ENI_NOHOSTNAME;
                        if (strlen(numaddr) > hostlen)
                                return ENI_MEMORY;
                        strcpy(host, numaddr);
                }
        }
        return SUCCESS;
}

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変数

struct afd afdl[] [static]

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