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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 <unistd.h>
#include <errno.h>
#include "dietfeatures.h"
#include "dietdns.h"
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;
}
static char hexdigit(char c) {
return c>9?c-10+'a':c+'0';
}
/* 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) {
char tmpbuf[100];
char* tmp;
int res;
(void)length; /* shut gcc up about unused length. The length is implicit with format */
#ifdef WANT_ETC_HOSTS
{
struct hostent* r;
while ((r=gethostent_r(buf,buflen))) {
if (r->h_addrtype==format && !memcmp(r->h_addr_list[0],addr,r->h_length)) { /* found it! */
memmove(result,r,sizeof(struct hostent));
*RESULT=result;
*h_errnop=0;
return 0;
}
}
endhostent();
}
#endif
if (format==AF_INET) {
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");
} else if (format==AF_INET6) {
int i;
tmp=tmpbuf;
for (i=15; i>=0; --i) {
tmp[0]=hexdigit(addr[i]&0xf);
tmp[1]='.';
tmp[2]=hexdigit((addr[i]>>4)&0xf);
tmp[3]='.';
tmp+=4;
}
strcpy(tmp,".ip6.int");
} else return 1;
if (buflen<sizeof(struct hostent)+16) {
errno=ENOMEM;
*h_errnop=NO_RECOVERY;
return 1;
}
res= __dns_gethostbyx_r(tmpbuf,result,buf+16,buflen-16,RESULT,h_errnop,12); /* 12 == ns_t_ptr */
if (res==0) {
if (format==AF_INET) {
result->h_length=4;
result->h_addrtype=format;
}
memcpy(buf,addr,result->h_length);
result->h_addr_list[0]=buf;
result->h_addr_list[1]=0;
}
return res;
}
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