From 7383225271fc38c0421f647c8e5fda26161f6079 Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Wed, 19 Nov 2008 15:16:16 +0000
Subject: [PATCH] - Brad Spencer brought the new function
ares_gethostbyname_file() which simply resolves a host name from the given
file, using the regular hosts syntax.
---
ares/CHANGES | 4 ++
ares/Makefile.inc | 2 +-
ares/ares.h | 2 +
ares/ares_gethostbyname.c | 25 ++++++++++
ares/ares_gethostbyname_file.3 | 84 ++++++++++++++++++++++++++++++++++
5 files changed, 116 insertions(+), 1 deletion(-)
create mode 100644 ares/ares_gethostbyname_file.3
diff --git a/ares/CHANGES b/ares/CHANGES
index c590079b4b..7e2875d961 100644
--- a/ares/CHANGES
+++ b/ares/CHANGES
@@ -1,5 +1,9 @@
Changelog for the c-ares project
+* Nov 19 2008 (Daniel Stenberg)
+- Brad Spencer brought the new function ares_gethostbyname_file() which simply
+ resolves a host name from the given file, using the regular hosts syntax.
+
* Nov 1 2008 (Daniel Stenberg)
- Carlo Contavalli added support for the glibc "rotate" option, as documented
in man resolv.conf:
diff --git a/ares/Makefile.inc b/ares/Makefile.inc
index d6bf0643a3..bdadd33428 100644
--- a/ares/Makefile.inc
+++ b/ares/Makefile.inc
@@ -19,4 +19,4 @@ MANPAGES= ares_destroy.3 ares_expand_name.3 ares_expand_string.3 ares_fds.3 \
ares_query.3 ares_search.3 ares_send.3 ares_strerror.3 ares_timeout.3 \
ares_version.3 ares_cancel.3 ares_parse_aaaa_reply.3 ares_getnameinfo.3 \
ares_getsock.3 ares_parse_ns_reply.3 \
- ares_destroy_options.3 ares_save_options.3
+ ares_destroy_options.3 ares_save_options.3 ares_gethostbyname_file.3
diff --git a/ares/ares.h b/ares/ares.h
index 1507f41e90..7ea70543fa 100644
--- a/ares/ares.h
+++ b/ares/ares.h
@@ -228,6 +228,8 @@ void ares_search(ares_channel channel, const char *name, int dnsclass,
int type, ares_callback callback, void *arg);
void ares_gethostbyname(ares_channel channel, const char *name, int family,
ares_host_callback callback, void *arg);
+int ares_gethostbyname_file(ares_channel channel, const char *name,
+ int family, struct hostent **host);
void ares_gethostbyaddr(ares_channel channel, const void *addr, int addrlen,
int family, ares_host_callback callback, void *arg);
void ares_getnameinfo(ares_channel channel, const struct sockaddr *sa,
diff --git a/ares/ares_gethostbyname.c b/ares/ares_gethostbyname.c
index a32da8f60a..9662db5aed 100644
--- a/ares/ares_gethostbyname.c
+++ b/ares/ares_gethostbyname.c
@@ -289,6 +289,31 @@ static int fake_hostent(const char *name, int family, ares_host_callback callbac
return 1;
}
+/* This is an API method */
+int ares_gethostbyname_file(ares_channel channel, const char *name,
+ int family, struct hostent **host)
+{
+ /* We only take the channel to ensure that ares_init() been called. */
+ if(channel == NULL)
+ {
+ /* Anything will do, really. This seems fine, and is consistent with
+ other error cases. */
+ *host = NULL;
+ return ARES_ENOTFOUND;
+ }
+
+ /* Just chain to the internal implementation we use here; it's exactly
+ * what we want.
+ */
+ const int result = file_lookup(name, family, host);
+ if(result != ARES_SUCCESS)
+ {
+ /* We guarantee a NULL hostent on failure. */
+ *host = NULL;
+ }
+ return result;
+}
+
static int file_lookup(const char *name, int family, struct hostent **host)
{
FILE *fp;
diff --git a/ares/ares_gethostbyname_file.3 b/ares/ares_gethostbyname_file.3
new file mode 100644
index 0000000000..860943bb3b
--- /dev/null
+++ b/ares/ares_gethostbyname_file.3
@@ -0,0 +1,84 @@
+.\" $Id$
+.\"
+.\" Copyright 1998 by the Massachusetts Institute of Technology.
+.\"
+.\" Permission to use, copy, modify, and distribute this
+.\" software and its documentation for any purpose and without
+.\" fee is hereby granted, provided that the above copyright
+.\" notice appear in all copies and that both that copyright
+.\" notice and this permission notice appear in supporting
+.\" documentation, and that the name of M.I.T. not be used in
+.\" advertising or publicity pertaining to distribution of the
+.\" software without specific, written prior permission.
+.\" M.I.T. makes no representations about the suitability of
+.\" this software for any purpose. It is provided "as is"
+.\" without express or implied warranty.
+.\"
+.TH ARES_GETHOSTBYNAME 3 "25 July 1998"
+.SH NAME
+ares_gethostbyname_file \- Lookup a name in the system's hosts file
+.SH SYNOPSIS
+.nf
+.B #include <ares.h>
+.PP
+.B void ares_gethostbyname_file(ares_channel \fIchannel\fP, const char *\fIname\fP,
+.B int \fIfamily\fP, struct hostent **host)
+.fi
+.SH DESCRIPTION
+The
+.B ares_gethostbyname_file
+function performs a host lookup by name against the system's hosts file (or equivalent local hostname database).
+The
+.IR channel
+parameter is required, but no asynchronous queries are performed. Instead, the
+lookup is done via the same mechanism used to perform 'f' lookups
+(see the
+.I lookups
+options field in \fIares_init_options(3)\fP).
+The parameter
+.I name
+gives the hostname as a NUL-terminated C string, and
+.I family
+gives the desired type of address for the resulting host entry.
+.PP
+The return value indicates whether the query succeeded and, if not, how it
+failed. It may have any of the following values:
+.TP 19
+.B ARES_SUCCESS
+The host lookup completed successfully and
+.I host
+now points to the result (and must be freed with \fIares_free_hostent(3)\fP).
+.TP 19
+.B ARES_ENOTFOUND
+The hostname
+.I name
+was not found.
+.TP 19
+.B ARES_EFILE
+There was a file I/O error while performing the lookup.
+.TP 19
+.B ARES_ENOMEM
+Memory was exhausted.
+.PP
+On successful completion of the query, the pointer pointed to by
+.I host
+points to a
+.B struct hostent
+containing the address of the host returned by the lookup. The user must
+free the memory pointed to by
+.IR host
+when finished with it by calling \fIares_free_hostent(3)\fP. If the lookup did
+not complete successfully,
+.I host
+will be
+.BR NULL .
+.SH AVAILABILITY
+Added in c-ares 1.5.4
+.SH SEE ALSO
+.BR ares_gethostbyname (3),
+.BR ares_free_hostent (3),
+.BR ares_init_options (3)
+.SH AUTHOR
+Brad Spencer
+.br
+Copyright 1998 by the Massachusetts Institute of Technology.
--
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