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#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include <sys/poll.h>
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
extern int __dns_gethostbyx_r(const char* name, struct hostent* result,
char *buf, size_t buflen,
struct hostent **RESULT, int *h_errnop, int lookfor);
static int i2a(char* dest,unsigned int x) {
register unsigned int tmp=x;
register int len=0;
if (x>=100) { *dest++=tmp/100+'0'; tmp=tmp%100; ++len; }
if (x>=10) { *dest++=tmp/10+'0'; tmp=tmp%10; ++len; }
*dest++=tmp+'0';
return len+1;
}
/* Oh boy, this interface sucks so badly, there are no words for it.
* Not one, not two, but _three_ error signalling methods! (*h_errnop
* nonzero? return value nonzero? *RESULT zero?) The glibc goons
* really outdid themselves with this one. */
int gethostbyaddr_r(const char* addr, size_t length, int format,
struct hostent* result, char *buf, size_t buflen,
struct hostent **RESULT, int *h_errnop) {
if (format==AF_INET) {
char tmpbuf[50];
char *tmp;
int res;
tmp=tmpbuf+i2a(tmpbuf,(unsigned char)addr[3]); *tmp++='.';
tmp+=i2a(tmp,(unsigned char)addr[2]); *tmp++='.';
tmp+=i2a(tmp,(unsigned char)addr[1]); *tmp++='.';
tmp+=i2a(tmp,(unsigned char)addr[0]); strcpy(tmp,".in-addr.arpa");
res= __dns_gethostbyx_r(tmpbuf,result,buf+4,buflen-4,RESULT,h_errnop,12); /* 12 == ns_t_ptr */
if (res==0) {
result->h_addr_list[0]=buf;
result->h_addr_list[1]=buf;
*(int*)buf=*(int*)addr;
}
return res;
}
return 1;
}
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