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#include "pthread.h"
#include <netdb.h>
#include <string.h>
static pthread_mutex_t getservby_mutex = PTHREAD_MUTEX_INITIALIZER;
static int
convert (struct servent *ret, struct servent *result,
char *buf, int buflen)
{
int len, i;
if (!buf) return -1;
*result = *ret;
/* This is the size. */
len = strlen (ret->s_name) + 1;
if (len > buflen) return -1;
buflen -= len;
result->s_name = (char *) buf;
buf += len;
strcpy (result->s_name, ret->s_name);
/* How many aliases and how big the buffer should be? There
is always a NULL pointer. */
for (len = sizeof (char *), i = 0; ret->s_aliases [i]; i++)
{
/* It should be size of (char *) and the length of string
plus 1. */
len += strlen (ret->s_aliases [i]) + 1 + sizeof (char *);
}
if (len > buflen) return -1;
buflen -= len;
/* This is an array of char * for s_aliases. */
result->s_aliases = (char **) buf;
buf += (i + 1) * sizeof (char *);
/* We copy the aliases now. */
for (i = 0; ret->s_aliases [i]; i++)
{
result->s_aliases [i] = (char *) buf;
strcpy (result->s_aliases [i], ret->s_aliases [i]);
buf += strlen (ret->s_aliases [i]) + 1;
}
/* This is the last one */
result->s_aliases [i] = NULL;
/* s_proto */
len = strlen (ret->s_proto) + 1;
if (len > buflen) return -1;
buf += len;
result->s_proto = (char *) buf;
strcpy (result->s_proto, ret->s_proto);
return 0;
}
struct servent *
getservbyport_r (int port, const char *proto,
struct servent *result, char *buffer, int buflen)
{
struct servent *ret;
pthread_mutex_lock (&getservby_mutex);
ret = getservbyport (port, proto);
if (!ret ||
convert (ret, result, buffer, buflen) != 0)
{
result = NULL;
}
pthread_mutex_unlock (&getservby_mutex);
return result;
}
struct servent *
getservbyname_r (const char *name, const char *proto,
struct servent *result, char *buffer, int buflen)
{
struct servent *ret;
pthread_mutex_lock (&getservby_mutex);
ret = getservbyname (name, proto);
if (!ret ||
convert (ret, result, buffer, buflen) != 0)
{
result = NULL;
}
pthread_mutex_unlock (&getservby_mutex);
return result;
}
struct servent *
getservent_r (struct servent *result, char *buffer, int buflen)
{
struct servent *ret;
pthread_mutex_lock (&getservby_mutex);
ret = getservent ();
if (!ret ||
convert (ret, result, buffer, buflen) != 0)
{
result = NULL;
}
pthread_mutex_unlock (&getservby_mutex);
return result;
}
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