Add new flag (DNS_CNAME_CALLBACK) for
evdns_base_resolve_ipv4()/evdns_base_resolve_ipv6().
If set, you will get one more callback with type == DNS_CNAME and CNAME
in addrs argument.
I recently found that when the network status changed when calling
bufferevent_socket_connect_hostname (e.g. switching between several
WIFIs), all DNS servers would fail, and the timeout of probe would be
very long if there were many DNS requests. I want libevent to support
manual setting of MAX_PROBE_TIMEOUT and TIMEOUT_BACKOFF_FACTOR
So move hardcoded MAX_PROBE_TIMEOUT and TIMEOUT_BACKOFF_FACTOR into
struct, and allow changing them.
Added new option `edns-udp-size` for evdns_base which allows
to control maximum allowed size of UDP DNS messages. This
maximum size is passed to the DNS server via edns mechanism.
- Documentation for `bufferevent_compat.h` and `rpc.h` is not generated
since the `@file` command is missing. It can be fixed by adding
`@file` in file comment block.
- The briefs of buffer.h,bufferevent.h and some other files are missing.
Adding `@brief` command can fix it.
- The parameters in the function declaration are different from the
parameters following the `@param` command.We should change them to the
same.
- Documentation of `watch.h` is not generated since `watch.h` has not
been added to the Doxyfile `INPUT` tag.
- Add link to the watch.h in event.h
This will allow to customize SO_RCVBUF/SO_SNDBUF for nameservers in this
evdns_base, you may want to adjust them if the kernel starts dropping
udp packages.
- DNS_OPTION_NAMESERVERS_NO_DEFAULT
Do not "default" nameserver (i.e. "127.0.0.1:53") if there is no nameservers
in resolv.conf, (iff DNS_OPTION_NAMESERVERS is set)
- EVDNS_BASE_NAMESERVERS_NO_DEFAULT
If EVDNS_BASE_INITIALIZE_NAMESERVERS isset, do not add default
nameserver if there are no nameservers in resolv.conf (just set
DNS_OPTION_NAMESERVERS_NO_DEFAULT internally)
Fixes: #569
"flush" can imply writing something out to a file or connection before
clearing it; "clear" always means "remove". It's also potentially
misleading to say "outdated" here, since the function removes _all_
addresses regardless, not just certain outdated ones.
Also, don't free the lock in this function. Also reindent the function.
As mentioned at https://sourceforge.net/p/levent/bugs/293/
created a small function "evdns_base_flush_outdated_host_addresses" which removes all the previous host addresses, if user wants to clean up the list of hosts can call and use this function.
Defination of this function is part of another patch.
Here is the brief description of problem:
When you are use evdns to resolve domains to IP adresses (see
./sample/dns-example) you loop never returns from event_base_dispatch(),
and because of this the program will never terminated.
Because existing programs may be depending on the old behavior, we
only apply the fix when evdns_base_new() is created with a new flag -
EVDNS_BASE_DISABLE_WHEN_INACTIVE.
(Commit message edited by Nick while squashing the branch.)
Previously we used include-guards with names like _EVENT2_EVENT_H_.
But C reserves macros beginning with an underscore for use by the
system. This patch converts all include guards for files like
include/event2/<fname.h> to be of form EVENT2_<FNAME_H>_INCLUDED_,
and all Libevent 1.x headers in include/<fname.h> to be of the form
EVENT1_<FNAME_H>_INCLUDED_, and all internal libevent headers with
names like <fname.h> to the form <FNAME_H>_INCLUDED_.
FNAME_H is here derived from fname.h by replacing every
non-macro-usable character in fname.h with an underscore, and
putting every remaining character in uppercase.
This is an automatic conversion. The script that produced was made by
running the following script over all header files:
=====
#!/usr/bin/perl -w
# Run this on every .h file except config.h, sys/queue.h, WIN32/event2/event-config.h
use strict;
my %macros = ();
my %skipped = ();
FILE: for my $fn (@ARGV) {
my $f = $fn;
if ($fn !~ /^\.\//) {
$f = "./$fn";
}
if ($f eq './config.h' or
$f =~ m#/tree.h$# or
$f =~ m#/queue.h# or
$f =~ m#/event-config.h# or
$f =~ m#/evconfig-private.h#) {
$skipped{$fn} = 1;
next FILE;
}
$skipped{$fn} = 0;
open(F, $fn);
while (<F>) {
if (/^#ifndef ([A-Za-z0-9_]+)/) {
$macros{$fn} = $1;
next FILE;
}
}
}
print "#!/usr/bin/perl -w -i -p\n\n";
for my $fn (@ARGV) {
if (! exists $macros{$fn}) {
print "# No macro known for $fn!\n" if (!$skipped{$fn});
} else {
if ($macros{$fn} !~ /_H_?$/) {
print "# Weird macro for $fn...\n";
}
my $goodmacro = uc $fn;
$goodmacro =~ s#^\./##;
$goodmacro =~ s#INCLUDE/EVENT2#EVENT2#;
$goodmacro =~ s#INCLUDE/#EVENT1_#;
$goodmacro =~ s#TEST/##;
$goodmacro =~ s#[\/\-\.]#_#g;
print "s/(?<![A-Za-z0-9_])$macros{$fn}(?![A-Za-z0-9_])/${goodmacro}_INCLUDED_/g;\n"
}
}
=== And then running the script below that it generated over all
=== the .h files again
#!/usr/bin/perl -w -i -p
s/(?<![A-Za-z0-9_])_BUFFEREVENT_INTERNAL_H_(?![A-Za-z0-9_])/BUFFEREVENT_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_CHANGELIST_H_(?![A-Za-z0-9_])/CHANGELIST_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_DEFER_INTERNAL_H_(?![A-Za-z0-9_])/DEFER_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVBUFFER_INTERNAL_H_(?![A-Za-z0-9_])/EVBUFFER_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT_INTERNAL_H_(?![A-Za-z0-9_])/EVENT_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVMAP_H_(?![A-Za-z0-9_])/EVMAP_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVRPC_INTERNAL_H_(?![A-Za-z0-9_])/EVRPC_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVSIGNAL_H_(?![A-Za-z0-9_])/EVSIGNAL_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVTHREAD_INTERNAL_H_(?![A-Za-z0-9_])/EVTHREAD_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT_HT_H(?![A-Za-z0-9_])/HT_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_HTTP_INTERNAL_H_(?![A-Za-z0-9_])/HTTP_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVDNS_H_(?![A-Za-z0-9_])/EVENT1_EVDNS_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT_H_(?![A-Za-z0-9_])/EVENT1_EVENT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_BUFFER_H_(?![A-Za-z0-9_])/EVENT2_BUFFER_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_BUFFER_COMPAT_H_(?![A-Za-z0-9_])/EVENT2_BUFFER_COMPAT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_BUFFEREVENT_H_(?![A-Za-z0-9_])/EVENT2_BUFFEREVENT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_BUFFEREVENT_COMPAT_H_(?![A-Za-z0-9_])/EVENT2_BUFFEREVENT_COMPAT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_BUFFEREVENT_SSL_H_(?![A-Za-z0-9_])/EVENT2_BUFFEREVENT_SSL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_BUFFEREVENT_STRUCT_H_(?![A-Za-z0-9_])/EVENT2_BUFFEREVENT_STRUCT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_DNS_H_(?![A-Za-z0-9_])/EVENT2_DNS_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_DNS_COMPAT_H_(?![A-Za-z0-9_])/EVENT2_DNS_COMPAT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_DNS_STRUCT_H_(?![A-Za-z0-9_])/EVENT2_DNS_STRUCT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_EVENT_H_(?![A-Za-z0-9_])/EVENT2_EVENT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_EVENT_COMPAT_H_(?![A-Za-z0-9_])/EVENT2_EVENT_COMPAT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_EVENT_STRUCT_H_(?![A-Za-z0-9_])/EVENT2_EVENT_STRUCT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_HTTP_H_(?![A-Za-z0-9_])/EVENT2_HTTP_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_HTTP_COMPAT_H_(?![A-Za-z0-9_])/EVENT2_HTTP_COMPAT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_HTTP_STRUCT_H_(?![A-Za-z0-9_])/EVENT2_HTTP_STRUCT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_EVENT_KEYVALQ_STRUCT_H_(?![A-Za-z0-9_])/EVENT2_KEYVALQ_STRUCT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_LISTENER_H_(?![A-Za-z0-9_])/EVENT2_LISTENER_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_RPC_H_(?![A-Za-z0-9_])/EVENT2_RPC_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_RPC_COMPAT_H_(?![A-Za-z0-9_])/EVENT2_RPC_COMPAT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_RPC_STRUCT_H_(?![A-Za-z0-9_])/EVENT2_RPC_STRUCT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_TAG_H_(?![A-Za-z0-9_])/EVENT2_TAG_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_TAG_COMPAT_H_(?![A-Za-z0-9_])/EVENT2_TAG_COMPAT_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_THREAD_H_(?![A-Za-z0-9_])/EVENT2_THREAD_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT2_UTIL_H_(?![A-Za-z0-9_])/EVENT2_UTIL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVHTTP_H_(?![A-Za-z0-9_])/EVENT1_EVHTTP_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVRPC_H_(?![A-Za-z0-9_])/EVENT1_EVRPC_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVUTIL_H_(?![A-Za-z0-9_])/EVENT1_EVUTIL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT_IOCP_INTERNAL_H(?![A-Za-z0-9_])/IOCP_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT_IPV6_INTERNAL_H(?![A-Za-z0-9_])/IPV6_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_LOG_H_(?![A-Za-z0-9_])/LOG_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_MIN_HEAP_H_(?![A-Za-z0-9_])/MINHEAP_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT_MM_INTERNAL_H(?![A-Za-z0-9_])/MM_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_RATELIM_INTERNAL_H_(?![A-Za-z0-9_])/RATELIM_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_STRLCPY_INTERNAL_H_(?![A-Za-z0-9_])/STRLCPY_INTERNAL_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_REGRESS_H_(?![A-Za-z0-9_])/REGRESS_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_TESTUTILS_H(?![A-Za-z0-9_])/REGRESS_TESTUTILS_H_INCLUDED_/g;
# Weird macro for test/tinytest.h...
s/(?<![A-Za-z0-9_])TINYTEST_H_INCLUDED_(?![A-Za-z0-9_])/TINYTEST_H_INCLUDED_/g;
# No macro known for test/tinytest_local.h!
# Weird macro for test/tinytest_macros.h...
s/(?<![A-Za-z0-9_])TINYTEST_MACROS_H_INCLUDED_(?![A-Za-z0-9_])/TINYTEST_MACROS_H_INCLUDED_/g;
s/(?<![A-Za-z0-9_])_EVENT_UTIL_INTERNAL_H(?![A-Za-z0-9_])/UTIL_INTERNAL_H_INCLUDED_/g;
Once, for reasons that made sense at the time, we had evdns.c use its
own logging subsystem with two levels, "warn" and "debug". This leads
to problems, since setting a log handler for Libevent wouldn't actually
trap these messages, since they weren't on by default, and since some of
the warns should really be msgs.
This patch changes the default behavior of evdns.c to log to
event_(debugx,warnx,msgx) by default, and adds a new (internal-use-only)
log level of EVDNS_LOG_MSG. Programs that set a evdns logging
function will see no change. Programs that don't will now see evdns
warnings reported like other warnings.
Previously, evdns was at the mercy of the user for providing a good
entropy source; without one, it would be vulnerable to various
active attacks.
This patch adds a port of OpenBSD's arc4random() calls to Libevent
[port by Chris Davis], and wraps it up a little bit so we can use it
more safely.
The 'flags' argument made sense when passed to
evdns_(base_)?parse_resolv_conf when it said which parts of the
resolv.conf file to obey. But for evdns_set_option(), it was really
silly, since you wouldn't be calling evdns_set_option() unless you
actually wanted to set the option. Its meaning was basically, "set
this to DNS_OPTIONS_ALL unless you want a funny surprise."
evdns_base_set_option was new in 2.0.1-alpha, so we aren't committed
to keeping it source-compatible.