diff options
Diffstat (limited to 'inet/inet_ntoa.c')
| -rw-r--r-- | inet/inet_ntoa.c | 146 |
1 files changed, 92 insertions, 54 deletions
diff --git a/inet/inet_ntoa.c b/inet/inet_ntoa.c index a37b1dbeef..b6087a982f 100644 --- a/inet/inet_ntoa.c +++ b/inet/inet_ntoa.c @@ -1,59 +1,97 @@ -/* - * Copyright (c) 1983, 1993 - * The Regents of the University of California. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#if defined(LIBC_SCCS) && !defined(lint) -static char sccsid[] = "@(#)inet_ntoa.c 8.1 (Berkeley) 6/4/93"; -#endif /* LIBC_SCCS and not lint */ - -/* - * Convert network-format internet address - * to base 256 d.d.d.d representation. - */ -#include <sys/types.h> -#include <netinet/in.h> -#include <arpa/inet.h> +/* Convert Inet number to ASCII representation. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + #include <stdio.h> +#include <stdlib.h> +#include <arpa/inet.h> +#include <libc-lock.h> + +/* The interface of this function is completely stupid, it requires a + static buffer. We relax this a bit in that we allow at least one + buffer for each thread. */ +__libc_lock_define_initialized (static, lock); + +/* This is the key for the thread specific memory. */ +static __libc_key_t key; + +/* Destructor for the thread-specific data. */ +static void free_key_mem (void *mem); + char * -inet_ntoa(in) - struct in_addr in; +inet_ntoa (struct in_addr in) { - static char b[18]; - register char *p; - - p = (char *)∈ -#define UC(b) (((int)b)&0xff) - (void)snprintf(b, sizeof(b), - "%d.%d.%d.%d", UC(p[0]), UC(p[1]), UC(p[2]), UC(p[3])); - return (b); + static char static_buf[18]; + static int initialized = 0; + char *buffer = NULL; + unsigned char *bytes; + + /* If we have not yet initialized the buffer do it now. */ + if (!initialized) + { + /* Make sure there is only one process doing the initialization. */ + __libc_lock_lock (lock); + + if (!initialized) + { + if (__libc_key_create (&key, free_key_mem)) + /* Creating the key failed. This either means we run + have only a single-threaded application or something + really went wrong. In any case use a static buffer + which is better than nothing. */ + buffer = static_buf; + } + + __libc_lock_unlock (lock); + } + + if (buffer == NULL) + { + /* We don't use the static buffer and so we have a key. Use it + to get the thread-specific buffer. */ + buffer = __libc_getspecific (key); + if (buffer == NULL) + { + /* No buffer allocated so far. */ + buffer = malloc (18); + if (buffer == NULL) + /* No more memory available. We use the static buffer. */ + buffer = static_buf; + else + __libc_setspecific (key, buffer); + } + } + + bytes = (unsigned char *) ∈ + snprintf (buffer, 18, "%d.%d.%d.%d", bytes[0], bytes[1], bytes[2], bytes[3]); + + return buffer; +} + + +static void +free_key_mem (void *mem) +{ + free (mem); + + /* And we must set the data to NULL so that the destructor is not + called again. */ + __libc_setspecific (key, NULL); } |