| 1 |
148 |
jeremybenn |
/* Convert Inet number to ASCII representation.
|
| 2 |
|
|
Copyright (C) 1997, 1998, 2000, 2001 Free Software Foundation, Inc.
|
| 3 |
|
|
This file is part of the GNU C Library.
|
| 4 |
|
|
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
|
| 5 |
|
|
|
| 6 |
|
|
The GNU C Library is free software; you can redistribute it and/or
|
| 7 |
|
|
modify it under the terms of the GNU Lesser General Public
|
| 8 |
|
|
License as published by the Free Software Foundation; either
|
| 9 |
|
|
version 2.1 of the License, or (at your option) any later version.
|
| 10 |
|
|
|
| 11 |
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
| 12 |
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
| 13 |
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
| 14 |
|
|
Lesser General Public License for more details.
|
| 15 |
|
|
|
| 16 |
|
|
You should have received a copy of the GNU Lesser General Public
|
| 17 |
|
|
License along with the GNU C Library; if not, write to the Free
|
| 18 |
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
| 19 |
|
|
02111-1307 USA. */
|
| 20 |
|
|
|
| 21 |
|
|
#include <stdio.h>
|
| 22 |
|
|
#include <stdlib.h>
|
| 23 |
|
|
#include <arpa/inet.h>
|
| 24 |
|
|
#include <bits/libc-lock.h>
|
| 25 |
|
|
|
| 26 |
|
|
/* The interface of this function is completely stupid, it requires a
|
| 27 |
|
|
static buffer. We relax this a bit in that we allow at least one
|
| 28 |
|
|
buffer for each thread. */
|
| 29 |
|
|
|
| 30 |
|
|
/* This is the key for the thread specific memory. */
|
| 31 |
|
|
static __libc_key_t key;
|
| 32 |
|
|
|
| 33 |
|
|
/* If nonzero the key allocation failed and we should better use a
|
| 34 |
|
|
static buffer than fail. */
|
| 35 |
|
|
static char local_buf[18];
|
| 36 |
|
|
static char *static_buf;
|
| 37 |
|
|
|
| 38 |
|
|
/* Destructor for the thread-specific data. */
|
| 39 |
|
|
static void init (void);
|
| 40 |
|
|
static void free_key_mem (void *mem);
|
| 41 |
|
|
|
| 42 |
|
|
|
| 43 |
|
|
char *
|
| 44 |
|
|
inet_ntoa (struct in_addr in)
|
| 45 |
|
|
{
|
| 46 |
|
|
__libc_once_define (static, once);
|
| 47 |
|
|
char *buffer;
|
| 48 |
|
|
unsigned char *bytes;
|
| 49 |
|
|
|
| 50 |
|
|
/* If we have not yet initialized the buffer do it now. */
|
| 51 |
|
|
__libc_once (once, init);
|
| 52 |
|
|
|
| 53 |
|
|
if (static_buf != NULL)
|
| 54 |
|
|
buffer = static_buf;
|
| 55 |
|
|
else
|
| 56 |
|
|
{
|
| 57 |
|
|
/* We don't use the static buffer and so we have a key. Use it
|
| 58 |
|
|
to get the thread-specific buffer. */
|
| 59 |
|
|
buffer = __libc_getspecific (key);
|
| 60 |
|
|
if (buffer == NULL)
|
| 61 |
|
|
{
|
| 62 |
|
|
/* No buffer allocated so far. */
|
| 63 |
|
|
buffer = malloc (18);
|
| 64 |
|
|
if (buffer == NULL)
|
| 65 |
|
|
/* No more memory available. We use the static buffer. */
|
| 66 |
|
|
buffer = local_buf;
|
| 67 |
|
|
else
|
| 68 |
|
|
__libc_setspecific (key, buffer);
|
| 69 |
|
|
}
|
| 70 |
|
|
}
|
| 71 |
|
|
|
| 72 |
|
|
bytes = (unsigned char *) ∈
|
| 73 |
|
|
snprintf (buffer, 18, "%d.%d.%d.%d",
|
| 74 |
|
|
bytes[0], bytes[1], bytes[2], bytes[3]);
|
| 75 |
|
|
|
| 76 |
|
|
return buffer;
|
| 77 |
|
|
}
|
| 78 |
|
|
|
| 79 |
|
|
|
| 80 |
|
|
/* Initialize buffer. */
|
| 81 |
|
|
static void
|
| 82 |
|
|
init (void)
|
| 83 |
|
|
{
|
| 84 |
|
|
if (__libc_key_create (&key, free_key_mem))
|
| 85 |
|
|
/* Creating the key failed. This means something really went
|
| 86 |
|
|
wrong. In any case use a static buffer which is better than
|
| 87 |
|
|
nothing. */
|
| 88 |
|
|
static_buf = local_buf;
|
| 89 |
|
|
}
|
| 90 |
|
|
|
| 91 |
|
|
|
| 92 |
|
|
/* Free the thread specific data, this is done if a thread terminates. */
|
| 93 |
|
|
static void
|
| 94 |
|
|
free_key_mem (void *mem)
|
| 95 |
|
|
{
|
| 96 |
|
|
free (mem);
|
| 97 |
|
|
__libc_setspecific (key, NULL);
|
| 98 |
|
|
}
|
