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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>
#include <ctype.h>
/* bsd extensions */
#include <sys/uio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include "priv.h"
enum
{
Nname= 6,
};
/*
* for inet addresses only
*/
struct servent*
getservbyname(char *name, char *proto)
{
int i, fd, m, num;
char *p, *bp;
int nn, na;
static struct servent s;
static char buf[1024];
static char *nptr[Nname+1];
num = 1;
for(p = name; *p; p++)
if(!isdigit(*p))
num = 0;
s.s_name = 0;
/* connect to server */
fd = open("/net/cs", O_RDWR);
if(fd < 0){
_syserrno();
return 0;
}
/* construct the query, always expect an ip# back */
if(num)
snprintf(buf, sizeof buf, "!port=%s %s=*", name, proto);
else
snprintf(buf, sizeof buf, "!%s=%s port=*", proto, name);
/* query the server */
if(write(fd, buf, strlen(buf)) < 0){
_syserrno();
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;;){
p = strchr(bp, '=');
if(p == 0)
break;
*p++ = 0;
if(strcmp(bp, proto) == 0){
if(nn < Nname)
nptr[nn++] = p;
} else if(strcmp(bp, "port") == 0){
s.s_port = htons(atoi(p));
}
while(*p && *p != ' ')
p++;
if(*p)
*p++ = 0;
bp = p;
}
if(nn+na == 0)
return 0;
nptr[nn] = 0;
s.s_aliases = nptr;
if(s.s_name == 0)
s.s_name = nptr[0];
return &s;
}
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