dns_caught_signal = 0;#if USE_UCIP_DIRECT		timerTempSeconds(10,dns_timeout,(void*)fd);		i=udpRead(fd,UNCACHED(packet),PACKETSZ);#else		oldalarm = alarm(REPLY_TIMEOUT);		oldhandler = signal(SIGALRM, dns_catch_signal);		i=read(fd, packet, PACKETSZ);		alarm(0);		signal(SIGALRM, oldhandler);		alarm(oldalarm);#endif		if (dns_caught_signal)		{        /* timed out, so retry send and receive,							to next nameserver on queue */			RESOLVDEBUG(("query timed out, retrying\n"));			goto again;		}#if USE_UCIP_DIRECT		else			timerCancel(dns_timeout,(void*)fd);#endif		if (i < HFIXEDSZ)		{			/* too short ! */			goto again;		}		decode_header(packet, &h);		RESOLVDEBUG(("id = %d, qr = %d\n", h.id, h.qr));		if ((h.id != id) || (!h.qr))		{			/* unsolicited */			goto again;		}		RESOLVDEBUG(("Got response %s\n", "(i think)!"));		RESOLVDEBUG(("qrcount=%d,ancount=%d,nscount=%d,arcount=%d\n",										h.qdcount, h.ancount, h.nscount, h.arcount));		RESOLVDEBUG(("opcode=%d,aa=%d,tc=%d,rd=%d,ra=%d,rcode=%d\n",										h.opcode, h.aa, h.tc, h.rd, h.ra, h.rcode));		if ((h.rcode) || (h.ancount < 1))		{			/* negative result, not present */			goto again;		}		pos = HFIXEDSZ;		for (j = 0; j < h.qdcount; j++)		{			RESOLVDEBUG(("Skipping question %d at %d\n", j, pos));			i = length_question(packet, pos);			RESOLVDEBUG(("Length of question %d is %d\n", j, i));			if (i < 0)				goto again;			pos += i;		}		RESOLVDEBUG(("Decoding answer at pos %d\n", pos));		for (j=0;j<h.ancount;j++)		{			i = decode_answer(packet, pos, &tmpA);			printf("dns_lookup:tmpA.dotted=%p\n",tmpA.dotted);			if (i<0)			{				RESOLVDEBUG(("failed decode %d\n", i));				goto again;			}			/* For all but T_SIG, accept first answer *///                    if (a->atype != T_SIG)//                      break;			//++cg[6/2/2001]: better search of the answers - prefer host address (type 1)			//                answers over other answers if possible.			if(a->atype==0)			{				*a=tmpA;			}else if(tmpA.atype==T_A){				free(a->dotted);				*a=tmpA;			}			if(tmpA.atype==T_A)				break;			if(tmpA.atype==T_SIG)				free(a->dotted);			pos += i;		}		RESOLVDEBUG(("Answer name = |%s|\n", a->dotted));		RESOLVDEBUG(("Answer type = |%d|\n", a->atype));#if USE_UCIP_DIRECT		udpClose(fd);#else		close(fd);#endif		if (outpacket)			*outpacket = packet;		else			free(packet);		printf("dns_lookup (end):a->dotted=%p\n",a->dotted);		return (0);                             /* success! */tryall:		/* if there are other nameservers, give them a go,			otherwise return with error */		variant = 0;		if (retries >= nscount*(searchdomains+1))				goto fail;again:		/* if there are searchdomains, try them or fallback as passed */		if (variant < searchdomains)		{			/* next search */			variant++;		} else {			/* next server, first search */			ns = (ns + 1) % nscount;			variant = 0;		}}fail:	if (fd != -1)#if USE_UCIP_DIRECT		udpClose(fd);#else		close(fd);#endif	if (lookup)		free(lookup);	if (packet)		free(packet);	return -1;}#endif#ifdef L_resolveaddressint resolve_address(const char *address, int nscount,        char **nsip, struct in_addr *in){        unsigned char *packet;        struct resolv_answer a;        char temp[256];        int i;        int nest = 0;        if (!address || !in)                return -1;        strncpy(temp, address, sizeof(temp));        for (;;) {                i = dns_lookup(temp, T_A, nscount, nsip, &packet, &a);								printf("resolve_address: a.dotted=%p\n",a.dotted);                if (i < 0)                        return -1;                free(a.dotted);                if (a.atype == T_CNAME) {               /* CNAME */                        i = decode_dotted(packet, a.rdoffset, temp, sizeof(temp));                        free(packet);                        if (i < 0)                                return -1;                        if (++nest > MAX_RECURSE)                                return -1;                        continue;                } else if (a.atype == T_A) {    /* ADDRESS */                        free(packet);                        break;                } else {                        free(packet);                        return -1;                }        }        if (in)            memcpy(in, a.rdata, INADDRSZ); /* IPv4 T_A */        return 0;}#endif#ifdef L_resolvemailboxint resolve_mailbox(const char *address,                                        int nscount, char **nsip, struct in_addr *in){        struct resolv_answer a;        unsigned char *packet;        char temp[256];        int nest = 0;        int i;        if (!address || !in)                return -1;        /* look up mail exchange */        i = dns_lookup(address, T_MX, nscount, nsip, &packet, &a);        strncpy(temp, address, sizeof(temp));        if (i >= 0) {                i = decode_dotted(packet, a.rdoffset+2, temp, sizeof(temp));                free(packet);        }        for (;;) {                i = dns_lookup(temp, T_A, nscount, nsip, &packet, &a);                if (i < 0)                        return -1;                free(a.dotted);                if (a.atype == T_CNAME) {               /* CNAME */                        i = decode_dotted(packet, a.rdoffset, temp, sizeof(temp));                        free(packet);                        if (i < 0)                                return i;                        if (++nest > MAX_RECURSE)                                return -1;                        continue;                } else if (a.atype == T_A) {    /* ADDRESS */                        free(packet);                        break;                } else {                        free(packet);                        return -1;                }        }        if (in)                memcpy(in, a.rdata, INADDRSZ); /* IPv4 */        return 0;}#endifextern int nameservers;extern char * nameserver[MAX_SERVERS];extern int searchdomains;extern const char * searchdomain[MAX_SEARCH];#ifdef L_opennameservers#if (USE_RESOLV_CONF==0)/** Number of nameservers to search */int nameservers=2;/** Array of nameserver address's */char * nameserverList[]={	"195.184.228.6",	"195.184.228.7"};char *nameserver[MAX_SERVERS];/** Number of search domains */int searchdomains=1;/** Array of search domains */const char *searchdomain[]={	"data-uncertain.co.uk"};#elseint nameservers=0;const char * nameserver[MAX_SERVERS];int searchdomains=0;const char * searchdomain[MAX_SEARCH];#endif#if USE_RESOLV_CONF#error "Reading the nameservers from /etc/resolv.conf doesn't work as I've not included cfgfind() in the build yet."int open_nameservers(){        FILE *fp;        int i;        if (nameservers > 0)            return 0;	RESOLVDEBUG(("open_nameservers()  [using /etc/resolv.conf]\n"));	// Nameservers from configuration file        if ((fp = fopen("/etc/resolv.conf", "r"))) {		if (0 != (arg = cfgfind(fp, "nameserver"))) {                        for (i=1; arg[i] && nameservers <= MAX_SERVERS; i++) {                                nameserver[nameservers++] = strdup(arg[i]);                                RESOLVDEBUG(("adding nameserver %s\n",arg[i]));                        }                }                if (0 != (arg = cfgfind(fp, "search"))) {                        for (i=1; arg[i] && searchdomains <= MAX_SEARCH; i++) {                                searchdomain[searchdomains++] = strdup(arg[i]);                                RESOLVDEBUG(("adding search %s\n",arg[i]));                        }                }                fclose(fp);        } else {            RESOLVDEBUG(("failed to open %s\n", "resolv.conf"));        }        RESOLVDEBUG(("nameservers = %d\n", nameservers));	return 0;}#endif#endif#ifdef L_closenameserversvoid close_nameservers(void){        while (nameservers > 0)                free((void*)nameserver[--nameservers]);}#endif#ifdef L_resolvenameconst char *resolve_name(const char *name, int mailbox){        struct in_addr in;        int i;        /* shortcut: is it a valid IP address to begin with? */        if (inet_aton(name, &in))                return name;#if USE_RESOLV_CONF        open_nameservers();#endif        RESOLVDEBUG(("looking up '%s', mailbox=%d, nameservers=%d\n",                        name, mailbox, nameservers));        if (mailbox)                i = resolve_mailbox(name, nameservers, nameserver, &in);        else                i = resolve_address(name, nameservers, nameserver, &in);        if (i < 0)                return 0;        RESOLVDEBUG(("success = '%s'\n", inet_ntoa(in)));        return inet_ntoa(in);}#endif#include <pthread.h>pthread_mutex_t resolvLock;void resolvInit(void){	pthread_mutex_init(&resolvLock,NULL);	nameservers=2;	nameserver[0]=strdup(nameserverList[0]);	nameserver[1]=strdup(nameserverList[1]);}/** * set nameservers * @param ns1 IP of primary nameserver * @param ns2 IP of secondary nameserver (or NULL if none) */void setNameServer(const char *ns1, const char *ns2){	if(nameserver[0])		free(nameserver[0]);	if(nameserver[1])		free(nameserver[1]);	nameservers=0;	if(ns1)	{		nameserver[nameservers]=strdup(ns1);		nameservers++;	}	if(ns2)	{		nameserver[nameservers]=strdup(ns2);		nameservers++;	}}#ifdef L_gethostbynametypedef struct {	char *name;	struct in_addr in;  struct in_addr *addr_list[2];	struct hostent h;} DNS_CACHE;#define DNS_CACHE_MAX 10static int cachePtr=0;static DNS_CACHE cache[DNS_CACHE_MAX]={	{NULL},	{NULL},	{NULL},	{NULL},	{NULL},	{NULL},	{NULL},	{NULL},	{NULL},	{NULL}};struct hostent *gethostbyname(const char *name){	char namebuf[512];	struct hostent *rtn=NULL;	unsigned char *packet;	struct resolv_answer a;	int i;	int nest = 0;	// do dns cache lookup...	for(i=0; i<DNS_CACHE_MAX; i++)	{		if((cache[i].name)&&(!strcmp(name,cache[i].name)))		{			printf("gethostbyname(%s): got cached address in slot %d\n",name,i);			return &cache[i].h;		}	}	printf("gethostbyname(%s): uncached, requesting from DNS\n",name);#ifdef ISS_OS	pthread_mutex_lock(&resolvLock);#endif	RESOLVDEBUG(("gethostbyname()\n"));#if USE_RESOLV_CONF	open_nameservers();#endif	if (!name)	{		RESOLVDEBUG(("no name\n"));#ifdef ISS_OS		pthread_mutex_unlock(&resolvLock);#endif		return 0;	}	memset(&cache[cachePtr].h, 0, sizeof(cache[cachePtr].h));	cache[cachePtr].addr_list[0] = &cache[cachePtr].in;	cache[cachePtr].addr_list[1] = 0;	strcpy(namebuf, name);	for (;;)	{		i = dns_lookup(namebuf, 1, nameservers, nameserver, &packet, &a);		if (i < 0)		{#ifdef ISS_OS			pthread_mutex_unlock(&resolvLock);#endif			return 0;		}		strncpy(namebuf, a.dotted, strlen(a.dotted));		printf("gethostbyname: a.dotted=%p\n",a);		free(a.dotted);		if (a.atype == T_CNAME)               /* CNAME */		{			i = decode_dotted(packet, a.rdoffset, namebuf, sizeof(namebuf));			free(packet);			if (i < 0)			{#ifdef ISS_OS				pthread_mutex_unlock(&resolvLock);#endif				return 0;			}			if (++nest > MAX_RECURSE)			{#ifdef ISS_OS					pthread_mutex_unlock(&resolvLock);#endif				return 0;			}			continue;		} else if (a.atype == T_A) {    /* ADDRESS */			memcpy(&cache[cachePtr].in, a.rdata, sizeof(cache[cachePtr].in));			printf("dns lookup, got addres for %s, caching in slot %d\n",name,cachePtr);			if(cache[cachePtr].name)				free(cache[cachePtr].name);			cache[cachePtr].name=strdup(name);			cache[cachePtr].h.h_name = cache[cachePtr].name;			cache[cachePtr].h.h_addrtype = AF_INET;			cache[cachePtr].h.h_length = sizeof(cache[cachePtr].in);			cache[cachePtr].h.h_addr_list = (char **) cache[cachePtr].addr_list;			rtn=&cache[cachePtr].h;			free(packet);			if(++cachePtr==DNS_CACHE_MAX)				cachePtr=0;			break;		} else {			free(packet);#ifdef ISS_OS			pthread_mutex_unlock(&resolvLock);#endif			return 0;		}	}#ifdef ISS_OS	pthread_mutex_unlock(&resolvLock);#endif	return rtn;}#endif#ifdef L_gethostbyaddrstruct hostent *gethostbyaddr(const char *addr, size_t len, int type){        static struct hostent h;        static char namebuf[256];        static struct in_addr in;        static struct in_addr *addr_list[2];        unsigned char *packet;        struct resolv_answer a;        int i;        int nest = 0;        if (!addr || (len != sizeof(in)) || (type != AF_INET))                return 0;        memcpy(&in.s_addr, addr, len);#if USE_RESOLV_CONF	open_nameservers();#endif        memset(&h, 0, sizeof(h));        addr_list[0] = &in;        addr_list[1] = 0;        sprintf(namebuf, "%d.%d.%d.%d.in-addr.arpa",                        (in.s_addr >> 24) & 0xff,                        (in.s_addr >> 16) & 0xff,                        (in.s_addr >> 8) & 0xff, (in.s_addr >> 0) & 0xff);        for (;;) {                i = dns_lookup(namebuf, T_PTR, nameservers, nameserver, &packet, &a);                if (i < 0)                        return 0;                strncpy(namebuf, a.dotted, sizeof(namebuf));                free(a.dotted);                if (a.atype == T_CNAME) {               /* CNAME */                        i = decode_dotted(packet, a.rdoffset, namebuf, sizeof(namebuf));                        free(packet);                        if (i < 0)                                return 0;                        if (++nest > MAX_RECURSE)                                return 0;                        continue;                } else if (a.atype == T_PTR) {  /* ADDRESS */                        i = decode_dotted(packet, a.rdoffset, namebuf, sizeof(namebuf));                        free(packet);                        h.h_name = namebuf;                        h.h_addrtype = AF_INET;                        h.h_length = sizeof(in);                        h.h_addr_list = (char **) addr_list;                        break;                } else {                        free(packet);                        return 0;                }        }        return &h;}#endif