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/* posix */
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
/* bsd extensions */
#include <sys/uio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include "priv.h"
int h_errno;
enum
{
Nname= 6,
};
/*
* for inet addresses only
*/
struct hostent*
gethostbyname(char *name)
{
int i, t, fd, m;
char *p, *k, *bp;
int nn, na;
struct in_addr in;
static struct hostent h;
static char buf[1024];
static char *nptr[Nname+1];
static char *aptr[Nname+1];
static char addr[Nname][4];
h.h_name = 0;
t = _sock_ipattr(name);
/* connect to server */
fd = open("/net/cs", O_RDWR);
if(fd < 0){
h_errno = NO_RECOVERY;
return 0;
}
/* construct the query, always expect an ip# back */
switch(t){
case Tsys:
snprintf(buf, sizeof buf, "!sys=%s ip=*", name);
break;
case Tdom:
snprintf(buf, sizeof buf, "!dom=%s ip=*", name);
break;
case Tip:
snprintf(buf, sizeof buf, "!ip=%s", name);
break;
}
/* query the server */
if(write(fd, buf, strlen(buf)) < 0){
h_errno = TRY_AGAIN;
close(fd);
return 0;
}
lseek(fd, 0, 0);
for(i = 0; i < sizeof(buf)-1; i += m){
m = read(fd, buf+i, sizeof(buf) - 1 - i);
if(m <= 0)
break;
buf[i+m++] = ' ';
}
close(fd);
buf[i] = 0;
/* parse the reply */
nn = na = 0;
for(bp = buf;;){
k = bp;
p = strchr(k, '=');
if(p == 0)
break;
*p++ = 0;
for(bp = p; *bp && *bp != ' '; bp++)
;
if(*bp)
*bp++ = 0;
if(strcmp(k, "dom") == 0){
if(h.h_name == 0)
h.h_name = p;
if(nn < Nname)
nptr[nn++] = p;
} else if(strcmp(k, "sys") == 0){
if(nn < Nname)
nptr[nn++] = p;
} else if(strcmp(k, "ip") == 0){
if(inet_aton(p, &in) == 0)
continue;
if(na < Nname){
memmove(addr[na], (unsigned char*)&in.s_addr, 4);
aptr[na] = addr[na];
na++;
}
}
}
if(nn+na == 0){
h_errno = HOST_NOT_FOUND;
return 0;
}
nptr[nn] = 0;
aptr[na] = 0;
h.h_aliases = nptr;
h.h_addr_list = aptr;
h.h_length = 4;
h.h_addrtype = AF_INET;
if(h.h_name == 0)
h.h_name = nptr[0];
if(h.h_name == 0)
h.h_name = aptr[0];
return &h;
}
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