#!/usr/local/bin/perl
# -*- indent-tabs-mode: nil; -*-
# vim:ft=perl:et:sw=4

# Sympa - SYsteme de Multi-Postage Automatique
#
# Copyright (c) 1997, 1998, 1999 Institut Pasteur & Christophe Wolfhugel
# Copyright (c) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
# 2006, 2007, 2008, 2009, 2010, 2011 Comite Reseau des Universites
# Copyright (c) 2011, 2012, 2013, 2014, 2015, 2016, 2017 GIP RENATER
# Copyright 2017, 2019, 2021, 2022 The Sympa Community. See the
# AUTHORS.md file at the top-level directory of this distribution and at
# <https://github.com/sympa-community/sympa.git>.
#
# 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 of the License, 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, see <http://www.gnu.org/licenses/>.

use lib split(/:/, $ENV{SYMPALIB} || ''), '/usr/local/libexec/sympa';
use strict;
use warnings;
use English qw(-no_match_vars);
use Getopt::Long;
use Pod::Usage;
use POSIX qw();

use Conf;
use Sympa::Constants;
use Sympa::Crash;    # Show traceback.
use Sympa::DatabaseManager;
use Sympa::Log;
use Sympa::Mailer;
use Sympa::Process;
use Sympa::Spindle::ProcessAutomatic;
use Sympa::Spool::Listmaster;
use Sympa::Tools::Data;

my $process = Sympa::Process->instance;
$process->init(pidname => 'sympa_automatic', name => 'sympa/automatic');

## Init random engine
srand(time());

# Check options.
my %options;
unless (
    GetOptions(
        \%main::options, 'debug|d', 'log_level=s',  'foreground',
        'config|f=s',    'mail|m',  'keepcopy|k=s', 'help|h',
        'version|v',
    )
) {
    pod2usage(-exitval => 1, -output => \*STDERR);
}
if ($main::options{'help'}) {
    pod2usage(0);
} elsif ($main::options{'version'}) {
    printf "Sympa %s\n", Sympa::Constants::VERSION;
    exit 0;
}
$Conf::sympa_config = $main::options{config};

if ($main::options{'debug'}) {
    $main::options{'log_level'} = 2 unless $main::options{'log_level'};
    $main::options{'foreground'} = 1;
}

my $log = Sympa::Log->instance;
$log->{log_to_stderr} = 'all' if $main::options{'foreground'};

my $mailer = Sympa::Mailer->instance;

_load();

# Put ourselves in background if we're not in debug mode.
unless ($main::options{'foreground'}) {
    $process->daemonize;
}

$log->openlog($Conf::Conf{'syslog'}, $Conf::Conf{'log_socket_type'});

# Create and write the PID file.
$process->write_pid(initial => 1);
# If process is running in foreground, don't write STDERR to a dedicated file.
unless ($main::options{foreground}) {
    $process->direct_stderr_to_file;
}

# Set the User ID & Group ID for the process
$GID = $EGID = (getgrnam(Sympa::Constants::GROUP))[2];
$UID = $EUID = (getpwnam(Sympa::Constants::USER))[2];

## Required on FreeBSD to change ALL IDs
## (effective UID + real UID + saved UID)
POSIX::setuid((getpwnam(Sympa::Constants::USER))[2]);
POSIX::setgid((getgrnam(Sympa::Constants::GROUP))[2]);

## Check if the UID has correctly been set (useful on OS X)
unless (($GID == (getgrnam(Sympa::Constants::GROUP))[2])
    && ($UID == (getpwnam(Sympa::Constants::USER))[2])) {
    die
        "Failed to change process user ID and group ID. Note that on some OS Perl scripts can't change their real UID. In such circumstances Sympa should be run via sudo.\n";
}

# Sets the UMASK
umask(oct($Conf::Conf{'umask'}));

## Most initializations have now been done.
$log->syslog(
    'notice',
    'Sympa/automatic %s Started',
    Sympa::Constants::VERSION()
);

sleep 1;    ## wait until main process has created required directories

## Do we have right access in the directory
if ($main::options{'keepcopy'}) {
    if (!-d $main::options{'keepcopy'}) {
        $log->syslog(
            'notice',
            'Cannot keep a copy of incoming messages: %s is not a directory',
            $main::options{'keepcopy'}
        );
        delete $main::options{'keepcopy'};
    } elsif (!-w $main::options{'keepcopy'}) {
        $log->syslog(
            'notice',
            'Cannot keep a copy of incoming messages: no write access to %s',
            $main::options{'keepcopy'}
        );
        delete $main::options{'keepcopy'};
    }
}

my $spindle = Sympa::Spindle::ProcessAutomatic->new(
    keepcopy  => $main::options{keepcopy},
    log_level => $main::options{log_level},
    log_smtp  => $main::options{mail}
);

# Catch signals, in order to exit cleanly, whenever possible.
$SIG{'TERM'} = 'sigterm';
$SIG{'INT'}  = 'sigterm';    # Interrupt from terminal.
$SIG{'HUP'}  = 'sighup';
$SIG{'PIPE'} = 'IGNORE';     # Ignore SIGPIPE ; prevents process from dying

# Main loop.
# This loop is run foreach HUP signal received.
# This is the main loop : look for files in the directory, handles
# them, sleeps a while and continues the good job.

while (not $spindle->{finish} or $spindle->{finish} ne 'term') {
    $spindle->spin;

    if ($spindle->{finish} and $spindle->{finish} eq 'hup') {
        # Disconnect from Database
        Sympa::DatabaseManager->disconnect;

        $log->syslog('notice', "Reloading sympa/automatic daemon");
        _load();
        $spindle = Sympa::Spindle::ProcessAutomatic->new(
            keepcopy  => $main::options{keepcopy},
            log_level => $main::options{log_level},
            log_smtp  => $main::options{mail}
        );
        next;
    } elsif ($spindle->{finish}) {
        last;
    }

    # If the spool was empty, sleep for a while.
    sleep $Conf::Conf{'sleep'};
}

# Purge grouped notifications
Sympa::Spool::Listmaster->instance->flush(purge => 1);

## Free zombie sendmail processes.
#Sympa::Process->instance->reap_child;

$log->syslog('notice', 'Sympa/automatic exited normally due to signal');
$process->remove_pid(final => 1);

exit(0);

# Load configuration.
sub _load {
    ## Load sympa.conf.
    unless (Conf::load(Conf::get_sympa_conf())) {    #Site and Robot
        die sprintf
            "Unable to load sympa configuration, file %s or one of the vhost robot.conf files contain errors. Exiting.\n",
            Conf::get_sympa_conf();
    }

    ## Open the syslog and say we're read out stuff.
    $log->openlog($Conf::Conf{'syslog'}, $Conf::Conf{'log_socket_type'});

    # Enable SMTP logging if required
    $mailer->{log_smtp} = $main::options{'mail'}
        || Sympa::Tools::Data::smart_eq($Conf::Conf{'log_smtp'}, 'on');

    # setting log_level using conf unless it is set by calling option
    if (defined $main::options{'log_level'}) {
        $log->{level} = $main::options{'log_level'};
        $log->syslog(
            'info',
            'Configuration file read, log level set using options: %s',
            $main::options{'log_level'}
        );
    } else {
        $log->{level} = $Conf::Conf{'log_level'};
        $log->syslog(
            'info',
            'Configuration file read, default log level %s',
            $Conf::Conf{'log_level'}
        );
    }

    # Check database connectivity.
    unless (Sympa::DatabaseManager->instance) {
        die sprintf
            "Database %s defined in sympa.conf is unreachable. verify db_xxx parameters in sympa.conf\n",
            $Conf::Conf{'db_name'};
    }

    ## Main program
    if (!chdir($Conf::Conf{'home'})) {
        die sprintf 'Can\'t chdir to %s: %s', $Conf::Conf{'home'}, $ERRNO;
        ## Function never returns.
    }

    ## Check for several files.
    unless (Conf::checkfiles_as_root()) {
        die "Missing files\n";
    }
}

############################################################
# sigterm
############################################################
#  When we catch signal, just changes the $spindle->{finish}.
#
# IN : -
#
# OUT : -
#
############################################################
sub sigterm {
    my $sig = shift;
    $log->syslog('notice',
        'Signal %s received, still processing current task', $sig);
    $spindle->{finish} = 'term';
}

############################################################
# sighup
############################################################
#  When we catch SIGHUP, changes the value of $spindle->{finish}
#  and puts the "-mail" logging option
#
# IN : -
#
# OUT : -
#
###########################################################
sub sighup {
    if ($mailer->{log_smtp}) {
        $log->syslog('notice',
            'signal HUP received, switch of the "-mail" logging option and continue current task'
        );
        $mailer->{log_smtp} = undef;
    } else {
        $log->syslog('notice',
            'signal HUP received, switch on the "-mail" logging option and continue current task'
        );
        $mailer->{log_smtp} = 1;
    }
    $spindle->{finish} = 'hup';
}

# Moved to Sympa::Spindle::ProcessAutomatic::_twist().
#sub process_message;

__END__

=encoding utf-8

=head1 NAME

sympa_automatic, sympa_automatic.pl - Automatic list creation daemon

=head1 SYNOPSIS

C<sympa_automatic.pl> S<[ C<-d, --debug> ]>
S<[ C<-f, --file>=I<another.sympa.conf> ]>
S<[ C<-k, --keepcopy>=I<directory> ]>
S<[ [ C<-m, --mail> ]>
S<[ C<-h, --help> ]> S<[ C<-v, --version> ]>

=head1 DESCRIPTION

Sympa_automatic.pl is a program which scans permanently the automatic creation
spool and processes each message.

If the list a message is bound for has not been there and list creation is
authorized, it will be created.  Then the message is stored into incoming
message spool again and wait for processing by F<sympa_msg.pl>.

=head1 OPTIONS

F<sympa_automatic.pl> may run with following options in general.

=over 4

=item C<-d>, C<--debug>

Enable debug mode.

=item C<-f>, C<--config=>I<file>

Force Sympa to use an alternative configuration file instead
of F</usr/local/etc/sympa/sympa.conf>.

=item C<--log_level=>I<level>

Sets Sympa log level.

=back

F<sympa_automatic.pl> may run in daemon mode with following options.

=over 4

=item C<--foreground>

The process remains attached to the TTY.

=item C<-k>, C<--keepcopy=>I<directory>

This option tells Sympa to keep a copy of every incoming message, 
instead of deleting them. `directory' is the directory to 
store messages.

=item C<-m>, C<--mail>

Sympa will log calls to sendmail, including recipients. This option is
useful for keeping track of each mail sent (log files may grow faster
though).

=back

With following options F<sympa_automatic.pl> will print some information and exit.

=over 4

=item C<-h>, C<--help>

Print this help message.

=item C<-v>, C<--version>

Print the version number.

=back

=head1 FILES

F</usr/local/etc/sympa/sympa.conf> main configuration file.

F<$PIDDIR/sympa_automatic.pid> this file contains the process ID
of F<sympa_automatic.pl>.

=head1 SEE ALSO

L<sympa.conf(5)>, L<sympa_msg(8)>.

L<Sympa::Spindle::ProcessAutomatic>.

=head1 HISTORY

F<sympa.pl> was originally written by:

=over 4

=item Serge Aumont

ComitE<233> RE<233>seau des UniversitE<233>s

=item Olivier SalaE<252>n

ComitE<233> RE<233>seau des UniversitE<233>s

=back

As of Sympa 6.2b.4, it was split into three programs:
F<sympa.pl> (later renamed to F<sympa>) command line utility,
F<sympa_automatic.pl> daemon and
F<sympa_msg.pl> daemon.

=cut
