X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fxgethostname.c;h=1f4d728a038210f0805b0a0b02891f24dc0b9c9d;hb=ecc43f7ce6220952bac7d8e751ca102c60f9f812;hp=f00d7bd5f53e35682b3abeef675ab8e94e00c4cc;hpb=a38bc613499aee7806cecf6615af4ad2a09def61;p=gnulib.git diff --git a/lib/xgethostname.c b/lib/xgethostname.c index f00d7bd5f..1f4d728a0 100644 --- a/lib/xgethostname.c +++ b/lib/xgethostname.c @@ -1,28 +1,84 @@ +/* xgethostname.c -- return current hostname with unlimited length + Copyright (C) 1992, 1996, 2000, 2001, 2003 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* written by Jim Meyering */ + +#ifdef HAVE_CONFIG_H +# include +#endif + +/* Specification. */ +#include "xgethostname.h" + +#include #include +#include +#ifndef errno +extern int errno; +#endif + +#include "error.h" +#include "exit.h" +#include "xalloc.h" + +#ifndef ENAMETOOLONG +# define ENAMETOOLONG 9999 +#endif + int gethostname (); -char *xmalloc (); -char *xrealloc (); -#define INITIAL_HOSTNAME_LENGTH 33 +#ifndef INITIAL_HOSTNAME_LENGTH +# define INITIAL_HOSTNAME_LENGTH 34 +#endif +/* Return the current hostname in malloc'd storage. + If malloc fails, exit. + Upon any other failure, return NULL. */ char * -xgethostname () +xgethostname (void) { char *hostname; size_t size; - int err; size = INITIAL_HOSTNAME_LENGTH; + /* Use size + 1 here rather than size to work around the bug + in SunOS 5.5's gethostname whereby it NUL-terminates HOSTNAME + even when the name is longer than the supplied buffer. */ + hostname = xmalloc (size + 1); while (1) { - hostname = xmalloc (size); - hostname[size - 1] = '\0'; + int k = size - 1; + int err; + + errno = 0; + hostname[k] = '\0'; err = gethostname (hostname, size); - if (err || hostname[size - 1] == '\0') + if (err >= 0 && hostname[k] == '\0') break; + else if (err < 0 && errno != ENAMETOOLONG && errno != 0) + { + int saved_errno = errno; + free (hostname); + errno = saved_errno; + return NULL; + } size *= 2; - hostname = xrealloc (hostname, size); + hostname = xrealloc (hostname, size + 1); } return hostname;