package Sys::Syslog;
use strict;
use Carp;
require 5.006;
require Exporter;
our $VERSION = '0.13';
our @ISA = qw(Exporter);
our %EXPORT_TAGS = (
standard => [qw(openlog syslog closelog setlogmask)],
extended => [qw(setlogsock)],
macros => [qw(
LOG_ALERT LOG_AUTH LOG_AUTHPRIV LOG_CONS LOG_CRIT LOG_CRON
LOG_DAEMON LOG_DEBUG LOG_EMERG LOG_ERR LOG_FACMASK LOG_FTP
LOG_INFO LOG_KERN LOG_LFMT LOG_LOCAL0 LOG_LOCAL1 LOG_LOCAL2
LOG_LOCAL3 LOG_LOCAL4 LOG_LOCAL5 LOG_LOCAL6 LOG_LOCAL7 LOG_LPR
LOG_MAIL LOG_NDELAY LOG_NEWS LOG_NFACILITIES LOG_NOTICE
LOG_NOWAIT LOG_ODELAY LOG_PERROR LOG_PID LOG_PRIMASK LOG_SYSLOG
LOG_USER LOG_UUCP LOG_WARNING
)],
);
our @EXPORT = (
@{$EXPORT_TAGS{standard}},
);
our @EXPORT_OK = (
@{$EXPORT_TAGS{extended}},
@{$EXPORT_TAGS{macros}},
);
# it would be nice to try stream/unix first, since that will be
# most efficient. However streams are dodgy - see _syslog_send_stream
my @connectMethods = ( 'tcp', 'udp', 'unix', 'stream', 'console' );
if ($^O =~ /^(freebsd|linux)$/) {
@connectMethods = grep { $_ ne 'udp' } @connectMethods;
}
my @defaultMethods = @connectMethods;
my $syslog_path = undef;
my $transmit_ok = 0;
my $current_proto = undef;
my $failed = undef;
my $fail_time = undef;
our ($connected, @fallbackMethods, $syslog_send, $host);
use Socket ':all';
use POSIX qw(strftime setlocale LC_TIME);
=head1 NAME
Sys::Syslog - Perl interface to the UNIX syslog(3) calls
=head1 VERSION
Version 0.13
=head1 SYNOPSIS
use Sys::Syslog; # all except setlogsock(), or:
use Sys::Syslog qw(:DEFAULT setlogsock); # default set, plus setlogsock()
use Sys::Syslog qw(:standard :macros); # standard functions, plus macros
setlogsock $sock_type;
openlog $ident, $logopt, $facility; # don't forget this
syslog $priority, $format, @args;
$oldmask = setlogmask $mask_priority;
closelog;
=head1 DESCRIPTION
C<Sys::Syslog> is an interface to the UNIX C<syslog(3)> program.
Call C<syslog()> with a string priority and a list of C<printf()> args
just like C<syslog(3)>.
=head1 EXPORTS
C<Sys::Syslog> exports the following C<Exporter> tags:
=over 4
=item *
C<:standard> exports the standard C<syslog(3)> functions:
openlog closelog setlogmask syslog
=item *
C<:extended> exports the Perl specific functions for C<syslog(3)>:
setlogsock
=item *
C<:macros> exports the symbols corresponding to most of your C<syslog(3)>
macros. See L<"CONSTANTS"> for the supported constants and their meaning.
=back
By default, C<Sys::Syslog> exports the symbols from the C<:standard> tag.
=head1 FUNCTIONS
=over 4
=item B<openlog($ident, $logopt, $facility)>
Opens the syslog.
C<$ident> is prepended to every message. C<$logopt> contains zero or
more of the words C<pid>, C<ndelay>, C<nowait>. The C<cons> option is
ignored, since the failover mechanism will drop down to the console
automatically if all other media fail. C<$facility> specifies the
part of the system to report about, for example C<LOG_USER> or C<LOG_LOCAL0>:
see your C<syslog(3)> documentation for the facilities available in
your system. Facility can be given as a string or a numeric macro.
This function will croak if it can't connect to the syslog daemon.
Note that C<openlog()> now takes three arguments, just like C<openlog(3)>.
B<You should use openlog() before calling syslog().>
B<Options>
=over 4
=item *
C<ndelay> - Open the connection immediately (normally, the connection is
opened when the first message is logged).
=item *
C<nowait> - Don't wait for child processes that may have been created
while logging the message. (The GNU C library does not create a child
process, so this option has no effect on Linux.)
=item *
C<pid> - Include PID with each message.
=back
B<Examples>
Open the syslog with options C<ndelay> and C<pid>, and with facility C<LOCAL0>:
openlog($name, "ndelay,pid", "local0");
Same thing, but this time using the macro corresponding to C<LOCAL0>:
openlog($name, "ndelay,pid", LOG_LOCAL0);
=item B<syslog($priority, $message)>
=item B<syslog($priority, $format, @args)>
If C<$priority> permits, logs C<$message> or C<sprintf($format, @args)>
with the addition that C<%m> in $message or C<$format> is replaced with
C<"$!"> (the latest error message).
C<$priority> can specify a level, or a level and a facility. Levels and
facilities can be given as strings or as macros.
If you didn't use C<openlog()> before using C<syslog()>, C<syslog()> will
try to guess the C<$ident> by extracting the shortest prefix of
C<$format> that ends in a C<":">.
B<Examples>
syslog("info", $message); # informational level
syslog(LOG_INFO, $message); # informational level
syslog("info|local0", $message); # information level, Local0 facility
syslog(LOG_INFO|LOG_LOCAL0, $message); # information level, Local0 facility
=over 4
=item B<Note>
C<Sys::Syslog> version v0.07 and older passed the C<$message> as the
formatting string to C<sprintf()> even when no formatting arguments
were provided. If the code calling C<syslog()> might execute with
older versions of this module, make sure to call the function as
C<syslog($priority, "%s", $message)> instead of C<syslog($priority,
$message)>. This protects against hostile formatting sequences that
might show up if $message contains tainted data.
=back
=item B<setlogmask($mask_priority)>
Sets the log mask for the current process to C<$mask_priority> and
returns the old mask. If the mask argument is 0, the current log mask
is not modified. See L<"Levels"> for the list of available levels.
B<Examples>
Only log errors:
setlogmask(LOG_ERR);
Log critical messages, errors and warnings:
setlogmask(LOG_CRIT|LOG_ERR|LOG_WARNING);
=item B<setlogsock($sock_type)>
=item B<setlogsock($sock_type, $stream_location)> (added in 5.004_02)
Sets the socket type to be used for the next call to
C<openlog()> or C<syslog()> and returns true on success,
C<undef> on failure.
A value of C<"unix"> will connect to the UNIX domain socket (in some
systems a character special device) returned by the C<_PATH_LOG> macro
(if your system defines it), or F</dev/log> or F</dev/conslog>,
whatever is writable. A value of 'stream' will connect to the stream
indicated by the pathname provided as the optional second parameter.
(For example Solaris and IRIX require C<"stream"> instead of C<"unix">.)
A value of C<"inet"> will connect to an INET socket (either C<tcp> or C<udp>,
tried in that order) returned by C<getservbyname()>. C<"tcp"> and C<"udp"> can
also be given as values. The value C<"console"> will send messages
directly to the console, as for the C<"cons"> option in the logopts in
C<openlog()>.
A reference to an array can also be passed as the first parameter.
When this calling method is used, the array should contain a list of
sock_types which are attempted in order.
The default is to try C<tcp>, C<udp>, C<unix>, C<stream>, C<console>.
Giving an invalid value for C<$sock_type> will croak.
=item B<closelog()>
Closes the log file and return true on success.
=back
=head1 EXAMPLES
openlog($program, 'cons,pid', 'user');
syslog('info', '%s', 'this is another test');
syslog('mail|warning', 'this is a better test: %d', time);
closelog();
syslog('debug', 'this is the last test');
setlogsock('unix');
openlog("$program $$", 'ndelay', 'user');
syslog('notice', 'fooprogram: this is really done');
setlogsock('inet');
$! = 55;
syslog('info', 'problem was %m'); # %m == $! in syslog(3)
# Log to UDP port on $remotehost instead of logging locally
setlogsock('udp');
$Sys::Syslog::host = $remotehost;
openlog($program, 'ndelay', 'user');
syslog('info', 'something happened over here');
=head1 CONSTANTS
=head2 Facilities
=over 4
=item *
C<LOG_AUTH> - security/authorization messages
=item *
C<LOG_AUTHPRIV> - security/authorization messages (private)
=item *
C<LOG_CRON> - clock daemon (B<cron> and B<at>)
=item *
C<LOG_DAEMON> - system daemons without separate facility value
=item *
C<LOG_FTP> - ftp daemon
=item *
C<LOG_KERN> - kernel messages
=item *
C<LOG_LOCAL0> through C<LOG_LOCAL7> - reserved for local use
=item *
C<LOG_LPR> - line printer subsystem
=item *
C<LOG_MAIL> - mail subsystem
=item *
C<LOG_NEWS> - USENET news subsystem
=item *
C<LOG_SYSLOG> - messages generated internally by B<syslogd>
=item *
C<LOG_USER> (default) - generic user-level messages
=item *
C<LOG_UUCP> - UUCP subsystem
=back
=head2 Levels
=over 4
=item *
C<LOG_EMERG> - system is unusable
=item *
C<LOG_ALERT> - action must be taken immediately
=item *
C<LOG_CRIT> - critical conditions
=item *
C<LOG_ERR> - error conditions
=item *
C<LOG_WARNING> - warning conditions
=item *
C<LOG_NOTICE> - normal, but significant, condition
=item *
C<LOG_INFO> - informational message
=item *
C<LOG_DEBUG> - debug-level message
=back
=head1 DIAGNOSTICS
=over 4
=item Invalid argument passed to setlogsock
B<(F)> You gave C<setlogsock()> an invalid value for C<$sock_type>.
=item no connection to syslog available
B<(F)> C<syslog()> failed to connect to the specified socket.
=item stream passed to setlogsock, but %s is not writable
B<(W)> You asked C<setlogsock()> to use a stream socket, but the given
path is not writable.
=item stream passed to setlogsock, but could not find any device
B<(W)> You asked C<setlogsock()> to use a stream socket, but didn't
provide a path, and C<Sys::Syslog> was unable to find an appropriate one.
=item tcp passed to setlogsock, but tcp service unavailable
B<(W)> You asked C<setlogsock()> to use a TCP socket, but the service
is not available on the system.
=item syslog: expecting argument %s
B<(F)> You forgot to give C<syslog()> the indicated argument.
=item syslog: invalid level/facility: %s
B<(F)> You specified an invalid level or facility, like C<LOG_KERN>
(which is reserved to the kernel).
=item syslog: too many levels given: %s
B<(F)> You specified too many levels.
=item syslog: too many facilities given: %s
B<(F)> You specified too many facilities.
=item syslog: level must be given
B<(F)> You forgot to specify a level.
=item udp passed to setlogsock, but udp service unavailable
B<(W)> You asked C<setlogsock()> to use a UDP socket, but the service
is not available on the system.
=item unix passed to setlogsock, but path not available
B<(W)> You asked C<setlogsock()> to use a UNIX socket, but C<Sys::Syslog>
was unable to find an appropriate an appropriate device.
=back
=head1 SEE ALSO
L<syslog(3)>
I<Syslogging with Perl>, L<http://lexington.pm.org/meetings/022001.html>
=head1 AUTHOR
Tom Christiansen E<lt>F<tchrist@perl.com>E<gt> and Larry Wall
E<lt>F<larry@wall.org>E<gt>.
UNIX domain sockets added by Sean Robinson
E<lt>F<robinson_s@sc.maricopa.edu>E<gt> with support from Tim Bunce
E<lt>F<Tim.Bunce@ig.co.uk>E<gt> and the C<perl5-porters> mailing list.
Dependency on F<syslog.ph> replaced with XS code by Tom Hughes
E<lt>F<tom@compton.nu>E<gt>.
Code for C<constant()>s regenerated by Nicholas Clark E<lt>F<nick@ccl4.org>E<gt>.
Failover to different communication modes by Nick Williams
E<lt>F<Nick.Williams@morganstanley.com>E<gt>.
Extracted from core distribution for publishing on the CPAN by
SE<eacute>bastien Aperghis-Tramoni E<lt>sebastien@aperghis.netE<gt>.
=head1 BUGS
Please report any bugs or feature requests to
C<bug-sys-syslog at rt.cpan.org>, or through the web interface at
L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Sys-Syslog>.
I will be notified, and then you'll automatically be notified of progress on
your bug as I make changes.
=head1 SUPPORT
You can find documentation for this module with the perldoc command.
perldoc Sys::Syslog
You can also look for information at:
=over 4
=item * AnnoCPAN: Annotated CPAN documentation
L<http://annocpan.org/dist/Sys-Syslog>
=item * CPAN Ratings
L<http://cpanratings.perl.org/d/Sys-Syslog>
=item * RT: CPAN's request tracker
L<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Sys-Syslog>
=item * Search CPAN
L<http://search.cpan.org/dist/Sys-Syslog>
=back
=head1 LICENSE
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut
sub AUTOLOAD {
# This AUTOLOAD is used to 'autoload' constants from the constant()
# XS function.
my $constname;
our $AUTOLOAD;
($constname = $AUTOLOAD) =~ s/.*:://;
croak "&Sys::Syslog::constant not defined" if $constname eq 'constant';
my ($error, $val) = constant($constname);
croak $error if $error;
no strict 'refs';
*$AUTOLOAD = sub { $val };
goto &$AUTOLOAD;
}
eval {
require XSLoader;
XSLoader::load('Sys::Syslog', $VERSION);
1
} or do {
require DynaLoader;
push @ISA, 'DynaLoader';
bootstrap Sys::Syslog $VERSION;
};
our $maskpri = &LOG_UPTO(&LOG_DEBUG);
sub openlog {
our ($ident, $logopt, $facility) = @_; # package vars
our $lo_pid = $logopt =~ /\bpid\b/;
our $lo_ndelay = $logopt =~ /\bndelay\b/;
our $lo_nowait = $logopt =~ /\bnowait\b/;
return 1 unless $lo_ndelay;
&connect;
}
sub closelog {
our $facility = our $ident = '';
&disconnect;
}
sub setlogmask {
my $oldmask = $maskpri;
$maskpri = shift unless $_[0] == 0;
$oldmask;
}
sub setlogsock {
my $setsock = shift;
$syslog_path = shift;
&disconnect if $connected;
$transmit_ok = 0;
@fallbackMethods = ();
@connectMethods = @defaultMethods;
if (ref $setsock eq 'ARRAY') {
@connectMethods = @$setsock;
} elsif (lc($setsock) eq 'stream') {
unless (defined $syslog_path) {
my @try = qw(/dev/log /dev/conslog);
if (length &_PATH_LOG) { # Undefined _PATH_LOG is "".
unshift @try, &_PATH_LOG;
}
for my $try (@try) {
if (-w $try) {
$syslog_path = $try;
last;
}
}
carp "stream passed to setlogsock, but could not find any device"
unless defined $syslog_path
}
unless (-w $syslog_path) {
carp "stream passed to setlogsock, but $syslog_path is not writable";
return undef;
} else {
@connectMethods = ( 'stream' );
}
} elsif (lc($setsock) eq 'unix') {
if (length _PATH_LOG() && !defined $syslog_path) {
$syslog_path = _PATH_LOG();
@connectMethods = ( 'unix' );
} else {
carp 'unix passed to setlogsock, but path not available';
return undef;
}
} elsif (lc($setsock) eq 'tcp') {
if (getservbyname('syslog', 'tcp') || getservbyname('syslogng', 'tcp')) {
@connectMethods = ( 'tcp' );
} else {
carp "tcp passed to setlogsock, but tcp service unavailable";
return undef;
}
} elsif (lc($setsock) eq 'udp') {
if (getservbyname('syslog', 'udp')) {
@connectMethods = ( 'udp' );
} else {
carp "udp passed to setlogsock, but udp service unavailable";
return undef;
}
} elsif (lc($setsock) eq 'inet') {
@connectMethods = ( 'tcp', 'udp' );
} elsif (lc($setsock) eq 'console') {
@connectMethods = ( 'console' );
} else {
croak "Invalid argument passed to setlogsock; must be 'stream', 'unix', 'tcp', 'udp' or 'inet'"
}
return 1;
}
sub syslog {
my $priority = shift;
my $mask = shift;
my ($message, $whoami);
my (@words, $num, $numpri, $numfac, $sum);
our $facility;
local($facility) = $facility; # may need to change temporarily.
croak "syslog: expecting argument \$priority" unless defined $priority;
croak "syslog: expecting argument \$format" unless defined $mask;
@words = split(/\W+/, $priority, 2);# Allow "level" or "level|facility".
undef $numpri;
undef $numfac;
foreach (@words) {
$num = &xlate($_); # Translate word to number.
if ($_ eq 'kern' || $num <= 0) {
croak "syslog: invalid level/facility: $_"
}
elsif ($num <= &LOG_PRIMASK) {
croak "syslog: too many levels given: $_" if defined($numpri);
$numpri = $num;
return 0 unless &LOG_MASK($numpri) & $maskpri;
}
else {
croak "syslog: too many facilities given: $_" if defined($numfac);
$facility = $_;
$numfac = $num;
}
}
croak "syslog: level must be given" unless defined($numpri);
if (!defined($numfac)) { # Facility not specified in this call.
$facility = 'user' unless $facility;
$numfac = &xlate($facility);
}
&connect unless $connected;
$whoami = our $ident;
if (!$whoami && $mask =~ /^(\S.*?):\s?(.*)/) {
$whoami = $1;
$mask = $2;
}
unless ($whoami) {
($whoami = getlogin) ||
($whoami = getpwuid($<)) ||
($whoami = 'syslog');
}
$whoami .= "[$$]" if our $lo_pid;
if ($mask =~ /%m/) {
my $err = $!;
# escape percent signs if sprintf will be called
$err =~ s/%/%%/g if @_;
# replace %m with $err, if preceded by an even number of percent signs
$mask =~ s/(?<!%)((?:%%)*)%m/$1$err/g;
}
$mask .= "\n" unless $mask =~ /\n$/;
$message = @_ ? sprintf($mask, @_) : $mask;
$sum = $numpri + $numfac;
my $oldlocale = setlocale(LC_TIME);
setlocale(LC_TIME, 'C');
my $timestamp = strftime "%b %e %T", localtime;
setlocale(LC_TIME, $oldlocale);
my $buf = "<$sum>$timestamp $whoami: $message\0";
# it's possible that we'll get an error from sending
# (e.g. if method is UDP and there is no UDP listener,
# then we'll get ECONNREFUSED on the send). So what we
# want to do at this point is to fallback onto a different
# connection method.
while (scalar @fallbackMethods || $syslog_send) {
if ($failed && (time - $fail_time) > 60) {
# it's been a while... maybe things have been fixed
@fallbackMethods = ();
disconnect();
$transmit_ok = 0; # make it look like a fresh attempt
&connect;
}
if ($connected && !connection_ok()) {
# Something was OK, but has now broken. Remember coz we'll
# want to go back to what used to be OK.
$failed = $current_proto unless $failed;
$fail_time = time;
disconnect();
}
&connect unless $connected;
$failed = undef if ($current_proto && $failed && $current_proto eq $failed);
if ($syslog_send) {
if (&{$syslog_send}($buf)) {
$transmit_ok++;
return 1;
}
# typically doesn't happen, since errors are rare from write().
disconnect();
}
}
# could not send, could not fallback onto a working
# connection method. Lose.
return 0;
}
sub _syslog_send_console {
my ($buf) = @_;
chop($buf); # delete the NUL from the end
# The console print is a method which could block
# so we do it in a child process and always return success
# to the caller.
if (my $pid = fork) {
our $lo_nowait;
if ($lo_nowait) {
return 1;
} else {
if (waitpid($pid, 0) >= 0) {
return ($? >> 8);
} else {
# it's possible that the caller has other
# plans for SIGCHLD, so let's not interfere
return 1;
}
}
} else {
if (open(CONS, ">/dev/console")) {
my $ret = print CONS $buf . "\r";
exit ($ret) if defined $pid;
close CONS;
}
exit if defined $pid;
}
}
sub _syslog_send_stream {
my ($buf) = @_;
# XXX: this only works if the OS stream implementation makes a write
# look like a putmsg() with simple header. For instance it works on
# Solaris 8 but not Solaris 7.
# To be correct, it should use a STREAMS API, but perl doesn't have one.
return syswrite(SYSLOG, $buf, length($buf));
}
sub _syslog_send_socket {
my ($buf) = @_;
return syswrite(SYSLOG, $buf, length($buf));
#return send(SYSLOG, $buf, 0);
}
sub xlate {
my($name) = @_;
return $name+0 if $name =~ /^\s*\d+\s*$/;
$name = uc $name;
$name = "LOG_$name" unless $name =~ /^LOG_/;
$name = "Sys::Syslog::$name";
# Can't have just eval { &$name } || -1 because some LOG_XXX may be zero.
my $value = eval { no strict 'refs'; &$name };
defined $value ? $value : -1;
}
sub connect {
@fallbackMethods = @connectMethods unless (scalar @fallbackMethods);
if ($transmit_ok && $current_proto) {
# Retry what we were on, because it's worked in the past.
unshift(@fallbackMethods, $current_proto);
}
$connected = 0;
my @errs = ();
my $proto = undef;
while ($proto = shift(@fallbackMethods)) {
no strict 'refs';
my $fn = "connect_$proto";
$connected = &$fn(\@errs) if defined &$fn;
last if ($connected);
}
$transmit_ok = 0;
if ($connected) {
$current_proto = $proto;
my($old) = select(SYSLOG); $| = 1; select($old);
} else {
@fallbackMethods = ();
croak join "\n\t- ", "no connection to syslog available", @errs
}
}
sub connect_tcp {
my ($errs) = @_;
my $tcp = getprotobyname('tcp');
if (!defined $tcp) {
push(@{$errs}, "getprotobyname failed for tcp");
return 0;
}
my $syslog = getservbyname('syslog','tcp');
$syslog = getservbyname('syslogng','tcp') unless (defined $syslog);
if (!defined $syslog) {
push(@{$errs}, "getservbyname failed for syslog/tcp and syslogng/tcp");
return 0;
}
my $this = sockaddr_in($syslog, INADDR_ANY);
my $that;
if (defined $host) {
$that = inet_aton($host);
if (!$that) {
push(@{$errs}, "can't lookup $host");
return 0;
}
} else {
$that = INADDR_LOOPBACK;
}
$that = sockaddr_in($syslog, $that);
if (!socket(SYSLOG,AF_INET,SOCK_STREAM,$tcp)) {
push(@{$errs}, "tcp socket: $!");
return 0;
}
setsockopt(SYSLOG, SOL_SOCKET, SO_KEEPALIVE, 1);
setsockopt(SYSLOG, IPPROTO_TCP, TCP_NODELAY, 1);
if (!CORE::connect(SYSLOG,$that)) {
push(@{$errs}, "tcp connect: $!");
return 0;
}
$syslog_send = \&_syslog_send_socket;
return 1;
}
sub connect_udp {
my ($errs) = @_;
my $udp = getprotobyname('udp');
if (!defined $udp) {
push(@{$errs}, "getprotobyname failed for udp");
return 0;
}
my $syslog = getservbyname('syslog','udp');
if (!defined $syslog) {
push(@{$errs}, "getservbyname failed for syslog/udp");
return 0;
}
my $this = sockaddr_in($syslog, INADDR_ANY);
my $that;
if (defined $host) {
$that = inet_aton($host);
if (!$that) {
push(@{$errs}, "can't lookup $host");
return 0;
}
} else {
$that = INADDR_LOOPBACK;
}
$that = sockaddr_in($syslog, $that);
if (!socket(SYSLOG,AF_INET,SOCK_DGRAM,$udp)) {
push(@{$errs}, "udp socket: $!");
return 0;
}
if (!CORE::connect(SYSLOG,$that)) {
push(@{$errs}, "udp connect: $!");
return 0;
}
# We want to check that the UDP connect worked. However the only
# way to do that is to send a message and see if an ICMP is returned
_syslog_send_socket("");
if (!connection_ok()) {
push(@{$errs}, "udp connect: nobody listening");
return 0;
}
$syslog_send = \&_syslog_send_socket;
return 1;
}
sub connect_stream {
my ($errs) = @_;
# might want syslog_path to be variable based on syslog.h (if only
# it were in there!)
$syslog_path = '/dev/conslog';
if (!-w $syslog_path) {
push(@{$errs}, "stream $syslog_path is not writable");
return 0;
}
if (!open(SYSLOG, ">" . $syslog_path)) {
push(@{$errs}, "stream can't open $syslog_path: $!");
return 0;
}
$syslog_send = \&_syslog_send_stream;
return 1;
}
sub connect_unix {
my ($errs) = @_;
if (length _PATH_LOG()) {
$syslog_path = _PATH_LOG();
} else {
push(@{$errs}, "_PATH_LOG not available in syslog.h");
return 0;
}
if (! -S $syslog_path) {
push(@{$errs}, "$syslog_path is not a socket");
return 0;
}
my $that = sockaddr_un($syslog_path);
if (!$that) {
push(@{$errs}, "can't locate $syslog_path");
return 0;
}
if (!socket(SYSLOG,AF_UNIX,SOCK_STREAM,0)) {
push(@{$errs}, "unix stream socket: $!");
return 0;
}
if (!CORE::connect(SYSLOG,$that)) {
if (!socket(SYSLOG,AF_UNIX,SOCK_DGRAM,0)) {
push(@{$errs}, "unix dgram socket: $!");
return 0;
}
if (!CORE::connect(SYSLOG,$that)) {
push(@{$errs}, "unix dgram connect: $!");
return 0;
}
}
$syslog_send = \&_syslog_send_socket;
return 1;
}
sub connect_console {
my ($errs) = @_;
if (!-w '/dev/console') {
push(@{$errs}, "console is not writable");
return 0;
}
$syslog_send = \&_syslog_send_console;
return 1;
}
# to test if the connection is still good, we need to check if any
# errors are present on the connection. The errors will not be raised
# by a write. Instead, sockets are made readable and the next read
# would cause the error to be returned. Unfortunately the syslog
# 'protocol' never provides anything for us to read. But with
# judicious use of select(), we can see if it would be readable...
sub connection_ok {
return 1 if (defined $current_proto && $current_proto eq 'console');
my $rin = '';
vec($rin, fileno(SYSLOG), 1) = 1;
my $ret = select $rin, undef, $rin, 0;
return ($ret ? 0 : 1);
}
sub disconnect {
$connected = 0;
$syslog_send = undef;
return close SYSLOG;
}
1;