/* Host name canonicalization
- Copyright (C) 2005 Free Software
- Foundation, Inc.
+ Copyright (C) 2005-2013 Free Software Foundation, Inc.
Written by Derek Price <derek@ximbiot.com>.
- 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 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 3, 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.
+ 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
#include "canon-host.h"
-#include "getaddrinfo.h"
-#include "strdup.h"
-
-
+#include <string.h>
+#include <netdb.h>
/* Store the last error for the single-threaded version of this function. */
static int last_cherror;
-
-
/* Single-threaded of wrapper for canon_host_r. After a NULL return, error
- messages may be retrieved via ch_strerror().
- */
+ messages may be retrieved via ch_strerror(). */
char *
canon_host (const char *host)
{
- return canon_host_r (host, &last_cherror);
+ return canon_host_r (host, &last_cherror);
}
-
-
-/* Returns a malloc'd string containing the canonical hostname associated with
- HOST, or NULL if a canonical name cannot be determined. On NULL return, if
- CHERROR is not NULL, *CHERROR will be set to an error code as returned by
- getaddrinfo(). Error codes from CHERROR may be converted to a string
- suitable for error messages by ch_strerror_r() or gai_strerror().
+/* Return a malloc'd string containing the canonical hostname associated with
+ HOST, or NULL if a canonical name cannot be determined. On NULL return,
+ if CHERROR is not NULL, set *CHERROR to an error code as returned by
+ getaddrinfo(). Use ch_strerror_r() or gai_strerror() to convert a *CHERROR
+ value to a string suitable for error messages.
WARNINGS
HOST must be a string representation of a resolvable name for this host.
getaddrinfo spec <http://www.opengroup.org/susv3xsh/getaddrinfo.html">,
RFC 1034 <http://www.faqs.org/rfcs/rfc1034.html>, & RFC 2181
<http://www.faqs.org/rfcs/rfc2181.html> for more on what this confusing
- term really refers to.
- */
+ term really refers to. */
char *
canon_host_r (char const *host, int *cherror)
{
- char *retval = NULL;
- static struct addrinfo hints;
- struct addrinfo *res = NULL;
- int status;
-
- hints.ai_flags = AI_CANONNAME;
- status = getaddrinfo (host, NULL, &hints, &res);
- if (!status)
+ char *retval = NULL;
+ static struct addrinfo hints;
+ struct addrinfo *res = NULL;
+ int status;
+
+ hints.ai_flags = AI_CANONNAME;
+ status = getaddrinfo (host, NULL, &hints, &res);
+ if (!status)
{
- retval = strdup (res->ai_canonname);
- freeaddrinfo (res);
+ /* http://lists.gnu.org/archive/html/bug-coreutils/2006-09/msg00300.html
+ says Darwin 7.9.0 getaddrinfo returns 0 but sets
+ res->ai_canonname to NULL. */
+ retval = strdup (res->ai_canonname ? res->ai_canonname : host);
+ if (!retval && cherror)
+ *cherror = EAI_MEMORY;
+ freeaddrinfo (res);
}
- else if (cherror)
- *cherror = status;
+ else if (cherror)
+ *cherror = status;
- return retval;
+ return retval;
}
-
-
/* Return a string describing the last error encountered by canon_host. */
const char *
ch_strerror (void)
{
- return gai_strerror (last_cherror);
+ return gai_strerror (last_cherror);
}