#
#   MailScanner - SMTP E-Mail Virus Scanner
#   Copyright (C) 2002  Julian Field
#
#   $Id: Sendmail.pm,v 1.56.2.22 2004/06/01 16:09:59 jkf Exp $
#
#   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, write to the Free Software
#   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
#   The author, Julian Field, can be contacted by email at
#      Jules@JulianField.net
#   or by paper mail at
#      Julian Field
#      Dept of Electronics & Computer Science
#      University of Southampton
#      Southampton
#      SO17 1BJ
#      United Kingdom
#

package MailScanner::Sendmail;

use strict 'vars';
use strict 'refs';
no  strict 'subs'; # Allow bare words for parameter %'s

use DirHandle;

use vars qw($VERSION);

### The package version, both in 1.23 style *and* usable by MakeMaker:
$VERSION = substr q$Revision: 1.56.2.22 $, 10;

# Command-line options you need to give to sendmail to sensibly process a
# message that is piped to it. Still need to add "-f" for specifying the
# envelope sender address. This is usually local postmaster.
my $SendmailOptions = "-t -oi -oem -F MailScanner -f";
my $UnsortedBatchesLeft;

# Attributes are
#
# $DFileRegexp                  set by new
# $HFileRegexp                  set by new
# $TFileRegexp                  set by new
# $QueueFileRegexp              set by new
# $LockType                     set by new
#


# If the sendmail and/or sendmail2 config variables aren't set, then
# set them to something sensible. This will need to be different
# for Exim.
sub initialise {
  MailScanner::Config::Default('sendmail', '/usr/sbin/sendmail');
  MailScanner::Config::Default('sendmail2',
                               MailScanner::Config::Value('sendmail'));
  $UnsortedBatchesLeft = 0; # Disable queue-clearing mode
}

# Constructor.
# Takes dir => directory queue resides in
sub new {
  my $type = shift;
  my $this = {};

  # These need to be improved
  # No change for V4
  $this->{DFileRegexp} = '^df([-\\w]*)$';
  $this->{HFileRegexp} = '^qf([-\\w]*)$';
  $this->{TFileRegexp} = '^tf([-\\w]*)$';
  $this->{QueueFileRegexp} = '^..([-\\w]*)$';

  # Patch by Kevin Spicer to detect HASFLOCK
  $this->{LockType} = "flock";
  # Automatically detect locking type
  #my $cmd = MailScanner::Config::Value('sendmail') . " -bt -d0.10 < /dev/null";
  #if ( grep /HASFLOCK/, `$cmd` ) {
  #  $this->{LockType} = "flock";
  #} else {
  #  $this->{LockType} = "posix";
  #}
  # End patch

  bless $this, $type;
  return $this;
}

# Required vars are:
#
# DFileRegexp:
# A regexp that will verify that a filename is a valid
# "DFile" name and leave the queue id in $1 if it is.
#
# HFileRegexp:
# A regexp that will verify that a filename is a valid
# "HFile" name and leave the queue id in $1 if it is.
#
# TFileRegexp:
# A regexp that will verify that a filename is a valid
# "TFile" name and leave the queue id in $1 if it is.
#
# QueueFileRegexp:
# A regexp that will match any legitimate queue file name
# and leave the queue id in $1.
#
# LockType:
# The way we should usually do spool file locking for
# this MTA ("posix" or "flock")
#
# Required subs are:
#
# DFileName: 
# Take a queue ID and return
# filename for data queue file
#
# HFileName:
# Take a queue ID and return
# filename for envelope queue file
#
# TFileName:
# Take a queue ID and return
# filename for temp queue file
#
# BuildMessageCmd:
# Return the shell command to take a mailscanner header file
# and an MTA message file, and build a plain text message
# (complete with headers)
#
# ReadQf:
# Read an envelope queue file (sendmail qf) and build
# an array of lines which together form all the mail headers.
#
# AddHeader:
# Given a current set of headers (string), and another header
# (key string, value string), return the set of headers with the new one
# added.
#
# DeleteHeader:
# Given a current set of headers (string), and another header
# (string), return the set of headers with the new one removed.
#
# ReplaceHeader:
# Given a current set of headers (string), and another header
# (key string, value string), return the set of headers with the new one
# in place of any existing occurence of the header.
#
# AppendHeader:
# Given a current set of headers (string), another header
# (key string, value string), and a separator string,
# return the set of headers with the new value
# appended to any existing occurrence of the header.
#
# PrependHeader:
# Given a current set of headers (string), another header
# (key string, value string), and a separator string,
# return the set of headers with the new value
# prepended to the front of any existing occurrence of the header.
# Do the header matching in a case-insensitive way.
#
# TextStartsHeader:
# Given a current set of headers (string), another header (string)
# and a search string,
# return true if the search string appears at the start of the
# text of the header.
# Do the matching in a case-insensitive way.
#
# AddRecipients:
# Return list of QF file lines for the passed recipients, which
# are comma-separated (with optional spaces with the commas).
#
# KickMessage:
# Given id, tell MTA to make a delivery attempt.
#
# CreateQf:
# Given a Message object, return a string containing the entire
# header file for this MTA.
#

# NOTE -- These were in list above; I believe that they are
# implementation details and should not be used outside this
# file. Looking further, they appear to be commented out here
# as well as in the Exim module -- nwp
#
# Internal subs:
#
# ConstructHeaders:
# Build a set of headers (in a string) ready to go into an MTA
# envelope file.
#
# ReadEnvelope:
# Given filehandle open for reading, read envelope lines into
# string and return it.
# 
# SplitEnvelope:
# Given complete envelope string, separate out header lines and
# return 2 strings, one containing the main part of the envelope,
# the other containing the headers.
#
# MergeEnvelope:
# Given main envelope body (from SplitEnvelope at the moment) and
# string of headers, merge them to form a complete envelope.
#
# MergeEnvelopeParts:
# Given filehandle open for reading, merge envelope data (excepting
# headers) from filehandle with headers from string, and return new
# envelope data in string, ready to be written back to new
# envelope queue file.
#

my($cat) = "/bin/cat";
my($sed) = "/bin/sed";

# Do conditional once at include time

#my($MTA) = MailScanner::Config::Value('mta');
#
#print STDERR "MTA is \"" . MailScanner::Config::Value('mta') . "\"\n";
#
#print STDERR "We are running sendmail\n";
#
#MailScanner::Log::InfoLog("Configuring mailscanner for sendmail...");

  sub DFileName {
    my($this, $id) = @_;
    return "df$id";
  }

  # No change for V4
  sub HFileName {
    my($this, $id) = @_;
    return "qf$id";
  }

  # No change for V4
  sub TFileName {
    my($this, $id) = @_;
    return "tf$id";
  }

#  sub BuildMessageCmd {
#    my($this, $hfile, $dfile) = @_;
#    return "$cat \"$hfile\" \"$dfile\"";
#  }

  # Change for V4: returns lower-case $from and @to
  sub ReadQf {
    my($this, $message) = @_;

    my($RQf) = $message->{store}{inhhandle};

    my($InHeader, @results, $msginfo, $from);
    my($ip, $Rline);
    my($Line, $Flags);
    my($RFound, $SFound, $IPFound);

    #$message->{store}->print();

    # Just in case we get a message with no headers at all
    @{$message->{headers}} = ();


    # Seek to the start of the file in case anyone read the file
    # between me opening it and locking it.
    seek($RQf, 0, 0);
    $InHeader = 0;
    while(<$RQf>) {
      last if /^\./; # Bat book section 23.9.19
      chomp; # Chomp everything now. We can easily add it back later.
      s/\015/ /g; # Sanitise everything by removing all embedded <CR>s
      s/\0//g;    # Remove all null bytes
      # JKF: You can get ASCII 13 (decimal) characters in the headers, which
      # can be used to embed attachments in the headers. Remember that in
      # most Unix environments, \n = ASCII 10 (decimal).
      # This is a *very* important s// command.
      $Line = $_;
      if ($Line =~ /^R/) {
        $Rline = $Line;
        #chomp $Rline;
        $Rline =~ s/^R([^:]*:)?//;
        $Rline =~ s/^<\s*//; # leading and
        $Rline =~ s/\s*>$//; # trailing <>
        push @{$message->{to}}, lc($Rline);
        $RFound = 1; # We have found a recipient
      }
      if ($Line =~ /^S/) {
        $from = $Line;
        #chomp $from;
        $from =~ s/^S//;
        $from =~ s/^<\s*//; # leading and
        $from =~ s/\s*>$//; # trailing <>
        $message->{from} = lc($from);
        $SFound = 1; # We have found the sender
      }
      if ($Line =~ /^\$_/) {
        $ip = $Line;
        #chomp $ip;
        if ($ip =~ /\[([\d.:abcdef]+)\]/) {
          $message->{clientip} = $1;
        } else {
          # It is a locally-created message and doesn't have an smtp client ip
          $message->{clientip} = '127.0.0.1';
        }
        $IPFound = 1; # We have found the client IP address
      }
      $InHeader = 1 if $Line =~ /^H/;
      if ($Line !~ /^[H\t ]/) {
        $InHeader = 0;
        push @{$message->{metadata}}, $_; # Put non-headers into @metadata
        next;
      }
      $Line =~ s/^H//;
      # JKF 18/04/2001 Delete ?flags? for 0 or more flags for sendmail 8.11
      $Line =~ s/^(\?[^?]*\?)//;
      $Flags = $1;
      # JKF 09/05/2002 Fix broken Return-Path: header bug
      if ($Line =~ /^Return-Path:/i) {
        $message->{returnpathflags} = $Flags;
        # JKF $Line =~ s/[\x80-\xff]/\$/g;
      }
      push @{$message->{headers}}, $Line;
      if ($Line =~ /^Subject:\s+(\S.*)$/i) {
        $message->{subject} = $1;
      }
    }
    # Not every qf file defined an IP address if it is a bounce.
    # So provide an IP if we haven't found one.
    $message->{clientip} = '0.0.0.0' unless $IPFound;

    # Every qf file should at least define the sender, 1 recipient and the
    # IP address. Everything else is optional, and is preserved as
    # MailScanner may not understand all the types of line.
    return 1 if $SFound && $RFound; # && $IPFound;
    #MailScanner::Log::WarnLog("Batch: Found invalid qf queue file for " .
    #                          "message %s", $message->{id});
    return 0;
  }


  # Add all the message headers to the metadata so it's ready to be
  # mangled and output to disk. Puts the headers at the end.
  # Can be passed in a string containing all the headers.
  # This is usually the output of stringify_output (MIME-Tools).
  # JKF: @headers doesn't include leading "H" header indicator.
  #      @metadata includes leading "H" but no \n characters.
  #      The input to this function can be a "\n"-separated string of
  #      new header lines. This is useful as the SpamCheck header can
  #      be flowed over multiple lines, but still be passed into here
  #      as a single header.
  sub AddHeadersToQf {
    my $this = shift;
    my($message, $headers) = @_;

    my($header, $h, @headerswithouth);

    if ($headers) {
      @headerswithouth = split(/\n/, $headers);
    } else {
      @headerswithouth = @{$message->{headers}};
    }

    foreach $header (@headerswithouth) {
      $h = $header;
      # Re-insert the header flags for Return-Path:
      $h = $message->{returnpathflags} . $h if $h =~ /^Return-Path:/i;
      $h =~ s/^\S/H$&/;
      push @{$message->{metadata}}, $h;
    }
  }

  sub AddHeader {
    my($this, $message, $newkey, $newvalue) = @_;
    push @{$message->{metadata}}, "H$newkey $newvalue";
  }

  sub DeleteHeader {
    my($this, $message, $key) = @_;

    my($linenum);
    for ($linenum=0; $linenum<@{$message->{metadata}}; $linenum++) {
      next unless $message->{metadata}[$linenum] =~ /^H(\?[^?]*\?)?$key/i;
      # Have found the right line
      splice(@{$message->{metadata}}, $linenum, 1);
      # Now delete the continuation lines
      while($message->{metadata}[$linenum] =~ /^\s/) {
        splice(@{$message->{metadata}}, $linenum, 1);
      }
      $linenum--; # Allow for 2 neighbouring instances of $key
    }
  }

  sub ReplaceHeader {
    my($this, $message, $key, $newvalue) = @_;

    $this->DeleteHeader($message, $key);
    $this->AddHeader($message, $key, $newvalue);
  }

  sub AppendHeader {
    my($this, $message, $key, $newvalue, $sep) = @_;

    my($linenum, $oldlocation, $totallines);

    # Try to find the old header
    $oldlocation = -1;
    $totallines = @{$message->{metadata}};

    # Find the start of the header
    for($linenum=0; $linenum<$totallines; $linenum++) {
      next unless $message->{metadata}[$linenum] =~ /^H(\?[^?]*\?)?$key/i;
      $oldlocation = $linenum;
      last;
    }

    # Didn't find it?
    if ($oldlocation<0) {
      $this->AddHeader($message, $key, $newvalue);
      return;
    }

    # Find the last line of the header
    do {
      $oldlocation++;
    } while($linenum<$totallines &&
            $message->{metadata}[$oldlocation] =~ /^\s/);
    $oldlocation--;

    # Add onto the end of the header
    $message->{metadata}[$oldlocation] .= "$sep$newvalue";
  }

  sub PrependHeader {
    my($this, $message, $key, $newvalue, $sep) = @_;

    my($linenum, $oldlocation);

    # Try to find the old header
    $oldlocation = -1;

    # Find the start of the header
    for($linenum=0; $linenum<@{$message->{metadata}}; $linenum++) {
      next unless $message->{metadata}[$linenum] =~ /^H(\?[^?]*\?)?$key/i;
      $oldlocation = $linenum;
      last;
    }

    # Didn't find it?
    if ($oldlocation<0) {
      $this->AddHeader($message, $key, $newvalue);
      return;
    }

    $message->{metadata}[$oldlocation] =~
      s/^H(\?[^?]*\?)?$key\s+/H$1$key $newvalue$sep/i;
  }

  sub TextStartsHeader {
    my($this, $message, $key, $text) = @_;

    my($linenum, $oldlocation);

    # Try to find the old header
    $oldlocation = -1;

    # Find the start of the header
    for($linenum=0; $linenum<@{$message->{metadata}}; $linenum++) {
      next unless $message->{metadata}[$linenum] =~ /^H(\?[^?]*\?)?$key/i;
      $oldlocation = $linenum;
      last;
    }

    # Didn't find it?
    if ($oldlocation<0) {
      return 0;
    }

    return 1 if $message->{metadata}[$oldlocation] =~
                                   /^H(\?[^?]*\?)?$key\s+\Q$text\E/i;
    return 0;
  }

  sub TextEndsHeader {
    my($this, $message, $key, $text) = @_;

    my($linenum, $oldlocation, $lastline, $totallines);

    # Try to find the old header
    $oldlocation = -1;
    $totallines = @{$message->{metadata}};

    # Find the start of the header
    for($linenum=0; $linenum<$totallines; $linenum++) {
      next unless $message->{metadata}[$linenum] =~ /^H(\?[^?]*\?)?$key/i;
      $oldlocation = $linenum;
      last;
    }

    # Didn't find it?
    if ($oldlocation<0) {
      return 0;
    }

    # Find the last line of the header
    $lastline = $oldlocation;
    do {
      $lastline++;
    } while($lastline<$totallines &&
            $message->{metadata}[$lastline] =~ /^H(\?[^?]*\?)?\s/);
    $lastline--;
    $key = '\s' unless $lastline == $oldlocation;

    return 1 if $message->{metadata}[$oldlocation] =~
                                   /^H(\?[^?]*\?)?$key.+\Q$text\E$/i;
    return 0;
  }


  #sub ConstructHeaders {
  #  my($headers) = @_;
  #  $headers =~ s/^\S/H$&/mg;
  #  return $headers;
  #}

  #sub ReadEnvelope {
  #  my($fh) = @_;
  #  my $envelope = "";
  #
  #  while(<$fh>) {
  #    last if /^\./; # Bat book section 23.9.19
  #    $envelope .= $_;
  #  }
  #  return $envelope;
  #}

  #sub SplitEnvelope {
  #  my($envelope) = @_;
#
#    my ($headers,$newenvelope);
#    my(@envelope) = split "\n", $envelope;
#
#    my $InHeader = 0;
#
#    while($_ = shift @envelope) {
#      last if /^\./; # Bat book section 23.9.19
#      if (/^H/) {
#        $InHeader = 1;
#        $headers .= "$_\n";
#        next;
#      }
#      if (/^\s/ && $InHeader) {
#        $headers .= "$_\n";
#        next;
#      }
#      $InHeader = 0;
#      $newenvelope .= "$_\n";
#    }
#
#    return ($newenvelope,$headers);
#  }

#  sub MergeEnvelope {
#    my ($envelope,$headers) = @_;
#    return "$envelope$headers.\n";
#  }

#  sub MergeEnvelopeParts {
#    my($fh, $headers) = @_;
#
#    my $envelope = "";
#    my $InHeader = 0;
#
#    while(<$fh>) {
#      last if /^\./; # Bat book section 23.9.19
#      ($InHeader = 1),next if /^H/;
#      next if /^\s/ && $InHeader;
#      $InHeader = 0;
#      $envelope .= $_;
#    }
#
#    $envelope .= $headers;
#    $envelope .= ".\n";
#    return $envelope;
#  }

  sub AddRecipients {
    my $this = shift;
    my($message, @recips) = @_;
    my($recip);
    foreach $recip (@recips) {
      push @{$message->{metadata}}, "RP:<$recip>";
    }
  }

  # Delete the original recipients from the message. We'll add some
  # using AddRecipients later.
  sub DeleteRecipients {
    my $this = shift;
    my($message) = @_;

    my($linenum);
    for ($linenum=0; $linenum<@{$message->{metadata}}; $linenum++) {
      # Looking for "recipient" lines
      next unless $message->{metadata}[$linenum] =~ /^R/;
      # Have found the right line
      splice(@{$message->{metadata}}, $linenum, 1);
      $linenum--; # Study the same line again
    }
  }


  sub KickMessage {
    my(@ids) = @_;
    my($idlist);

    $idlist = join(' -qI', @ids);
    $idlist .= ' &' if MailScanner::Config::Value('deliverinbackground');
    #print STDERR "About to do \"Sendmail2 -qI$idlist\"\n";
    system(MailScanner::Config::Value('sendmail2') . ' -qI' . $idlist);
  }

  sub CreateQf {
    my($message) = @_;

    return join("\n", @{$message->{metadata}}) . "\n.\n";
  }


  # Append, add or replace a given header with a given value.
  sub AddMultipleHeader {
    my $this = shift;
    my($message, $headername, $headervalue, $separator) = @_;

    my($multiple) = MailScanner::Config::Value('multipleheaders', $message);
    $this->AppendHeader ($message,
                         MailScanner::Config::Value(lc($headername), $message),
                         $headervalue, $separator)
      if $multiple eq 'append';

    $this->AddHeader    ($message,
                         MailScanner::Config::Value(lc($headername), $message),
                         $headervalue)
      if $multiple eq 'add';

    $this->ReplaceHeader($message,
                         MailScanner::Config::Value(lc($headername), $message),
                         $headervalue)
      if $multiple eq 'replace';
  }


  # Send an email message containing all the headers and body in a string.
  # Also passed in the sender's address.
  sub SendMessageString {
    my $this = shift;
    my($message, $email, $sender) = @_;

    my($fh);

    #print STDERR '|' . MailScanner::Config::Value('sendmail', $message) .
    #          ' ' . $SendmailOptions . '-f ' . "'$sender'" . "\n";
    $fh = new FileHandle;
    $fh->open('|' . MailScanner::Config::Value('sendmail', $message) .
              " $SendmailOptions '" . $sender . "'")
      or MailScanner::Log::WarnLog("Could not send email message, %s", $!),
         return 0;
    #$fh->open('|cat >> /tmp/1');
    $fh->print($email);
    #print STDERR $email;
    $fh->close();

    1;
  }


  # Send an email message containing the attached MIME entity.
  # Also passed in the sender's address.
  sub SendMessageEntity {
    my $this = shift;
    my($message, $entity, $sender) = @_;

    my($fh);

    #print STDERR  '|' . MailScanner::Config::Value('sendmail', $message) .
    #          ' ' . $SendmailOptions . '-f ' . $sender . "\n";
    $fh = new FileHandle;
    $fh->open('|' . MailScanner::Config::Value('sendmail', $message) .
              " $SendmailOptions '" . $sender . "'")
      or MailScanner::Log::WarnLog("Could not send email entity, %s", $!),
         return 0;
    #$fh->open('|cat >> /tmp/2');
    $entity->print($fh);
    #$entity->print(\*STDERR);
    $fh->close();

    1;
  }

  # Create a MessageBatch object by reading the queue and filling in
  # the passed-in batch object.
  sub CreateBatch {
    my $this = shift;
    my($batch) = @_;

    my($queuedirname, $queuedir, $MsgsInQueue);
    my($DirtyMsgs, $DirtyBytes, $CleanMsgs, $CleanBytes);
    my($HitLimit1, $HitLimit2, $HitLimit3, $HitLimit4);
    my($MaxCleanB, $MaxCleanM, $MaxDirtyB, $MaxDirtyM);
    my(%ModDate, $mta, $file, $tmpdate, $invalidfiles);
    my(@SortedFiles, $id, $newmessage, @queuedirnames);
    my($batchempty, $CriticalQueueSize, $headerfileumask);

    # Old code left over from single queue dir
    #$queuedirname = $global::MS->{inq}{dir};
    #chdir $queuedirname or Log::DieLog("Cannot cd to dir %s to read " .
    #                                   "messages, %s", $queuedirname, $!);

    $queuedir = new DirHandle;
    $MsgsInQueue = 0;
    #print STDERR "Inq = " . $global::MS->{inq} . "\n";
    #print STDERR "dir = " . $global::MS->{inq}{dir} . "\n";
    @queuedirnames = @{$global::MS->{inq}{dir}};

    ($MaxCleanB, $MaxCleanM, $MaxDirtyB, $MaxDirtyM)
                      = MailScanner::MessageBatch::BatchLimits();

    # If there are too many messages in the queue, start processing in
    # directory storage order instead of date order.
    $CriticalQueueSize = MailScanner::Config::Value('criticalqueuesize');

    # Set what we will need the umask to be
    $headerfileumask = $global::MS->{work}->{fileumask};

    do {
      $batch->{messages} = {};
      # Statistics logging
      $batch->{totalbytes} = 0;
      $batch->{totalmessages} = 0;

      #
      # Now do the actual work
      #
      $DirtyMsgs  = 0;
      $DirtyBytes = 0;
      $CleanMsgs  = 0;
      $CleanBytes = 0;
      $MsgsInQueue = 0;
      %ModDate = ();
      @SortedFiles = ();
      $HitLimit1  = 0;
      $HitLimit2  = 0;
      $HitLimit3  = 0;
      $HitLimit4  = 0;
      $invalidfiles = "";

      my @aux_queuedirnames=@queuedirnames;

      # Loop through each of the inq directories
      while( defined($queuedirname=splice(@aux_queuedirnames,
                    ($UnsortedBatchesLeft<=0 ? 0 : int(rand(@aux_queuedirnames))),1))) {
        #print STDERR "Scanning dir $queuedirname\n";
        unless (chdir $queuedirname) {
          MailScanner::Log::WarnLog("Cannot cd to dir %s to read messages, %s",
                       $queuedirname, $!);
          next;
        }

        $queuedir->open('.')
          or MailScanner::Log::DieLog("Cannot open queue dir %s for reading " .
                                      "message batch, %s", $queuedirname, $!);
        $mta = $global::MS->{mta};
        #print STDERR "Searching " . $queuedirname . " for messages\n";

        # Read in modification dates of the qf files & use them in date order
        while(defined($file = $queuedir->read())) {
          # Optimised by binning the 50% that aren't H files first
          next unless $file =~ /$mta->{HFileRegexp}/;
          #print STDERR "Found message file $file\n";
          $MsgsInQueue++; # Count the size of the queue
          push @SortedFiles, "$queuedirname/$file";
          if ($UnsortedBatchesLeft<=0) {
            # Running normally
            $tmpdate = (stat($file))[9]; # 9 = mtime
            next unless -f _;
            next if -z _; # Skip 0-length qf files
            $ModDate{"$queuedirname/$file"} = $tmpdate; # Push msg into list
            #print STDERR "Stored message file $file\n";
          }
        }
        $queuedir->close();
      }

      # Not sorting the queue will save us considerably more time than
      # just skipping the sort operation, as it will enable the next bit
      # of code to just use the files nearest the beginning of the directory.
      # This should make the directory lookups much faster on filesystems
      # with slow directory lookups (e.g. anything except xfs).
      $UnsortedBatchesLeft = 40
        if $CriticalQueueSize>0 && $MsgsInQueue>=$CriticalQueueSize;
      # SortedFiles is array of full pathnames now, not just filenames
      if ($UnsortedBatchesLeft>0) {
        $UnsortedBatchesLeft--;
      } else {
        @SortedFiles = sort { $ModDate{$a} <=> $ModDate{$b} } keys %ModDate;
      }

      $batchempty = 1;

      # Keep going until end of dir or have reached every imposed limit. This
      # now processes the files oldest first to make for fairer queue cleanups.
      #print STDERR "Files are " . join(', ', @SortedFiles) . "\n";
      umask $headerfileumask; # Start creating files
      while(defined($file = shift @SortedFiles) &&
            $HitLimit1+$HitLimit2+$HitLimit3+$HitLimit4<1) {
        # In accelerated mode, so we don't know anything about this file
        if ($UnsortedBatchesLeft>0) {
          stat $file;
          next unless -f _;
          next if     -z _;
        }

        # must separate next two lines or $1 gets re-tainted by being part of
        # same expression as $file [mumble mumble grrr mumble mumble]
        #print STDERR "Reading file $file from list\n";
        # Split pathname into dir and file again
        ($queuedirname, $file) = ($1,$2) if $file =~ /^(.*)\/([^\/]+)$/;
        next unless $file =~ /$mta->{HFileRegexp}/;
        $id = $1;

        #print STDERR "Adding $id to batch\n";

        # Lock and read the qf file. Skip this message if the lock fails.
        $newmessage = MailScanner::Message->new($id, $queuedirname);
        if ($newmessage eq 'INVALID') {
          $invalidfiles .= "$id ";
          next;
        }
        next unless $newmessage;

        $batch->{messages}{"$id"} = $newmessage;
        $batchempty = 0;

        if (MailScanner::Config::Value("virusscan", $newmessage)) {
          $newmessage->NeedsScanning(1);
          $DirtyMsgs++;
          $DirtyBytes += $newmessage->{size};
          $HitLimit3 = 1
            if $DirtyMsgs>=$MaxDirtyM;
          $HitLimit4 = 1
            if $DirtyBytes>=$MaxDirtyB;
          $newmessage->WriteHeaderFile(); # Write the file of headers
        } else {
          $newmessage->NeedsScanning(0);
          $CleanMsgs++;
          $CleanBytes += $newmessage->{size};
          $HitLimit1 = 1
            if $CleanMsgs>=$MaxCleanM;
          $HitLimit2 = 1
            if $CleanBytes>=$MaxCleanB;
          # Will have to add a WriteHeaderFile() here to implement
          # single-file archiving of messages.
          $newmessage->WriteHeaderFile(); # Write the file of headers
        }
      }
      umask 0077; # Safety net as stopped creating files now

      # Wait a bit until I check the queue again
      sleep(MailScanner::Config::Value('queuescaninterval')) if $batchempty;
    } while $batchempty; # Keep trying until we get something

    # Log the number of invalid messages found
    MailScanner::Log::InfoLog("New Batch: Found invalid queue files: %s",
                              $invalidfiles)
      if $invalidfiles;
    # Log the size of the queue if it is more than 1 batch
    MailScanner::Log::InfoLog("New Batch: Found %d messages waiting",
                              $MsgsInQueue)
      if $MsgsInQueue > ($DirtyMsgs+$CleanMsgs);

    MailScanner::Log::InfoLog("New Batch: Forwarding %d unscanned messages, " .
                              "%d bytes", $CleanMsgs, $CleanBytes)
      if $CleanMsgs;
    MailScanner::Log::InfoLog("New Batch: Scanning %d messages, %d bytes",
                              $DirtyMsgs, $DirtyBytes)
      if $DirtyMsgs;

    #MailScanner::Log::InfoLog("New Batch: Archived %d $ArchivedMsgs messages",
    #                          $ArchivedMsgs)
    #  if $ArchivedMsgs;

    $batch->{dirtymessages} = $DirtyMsgs;
    $batch->{dirtybytes}    = $DirtyBytes;

    # Logging stats
    $batch->{totalmessages} = $DirtyMsgs  + $CleanMsgs;
    $batch->{totalbytes}    = $DirtyBytes + $CleanBytes;

    #print STDERR "Dirty stats are $DirtyMsgs msgs, $DirtyBytes bytes\n";
  }


# Return the array of headers from this message, optionally with a
# separator on the end of each one.
# This is in Sendmail.pm as the storage of the headers array is specific
# to the MTA being used.
sub OriginalMsgHeaders {
  my $this = shift;
  my($message, $separator) = @_;

  # No separator so just return the array
  return @{$message->{headers}} unless $separator;

  # There is a separator
  my($h,@result);
  foreach $h (@{$message->{headers}}) {
    push @result, $h . $separator;
  }
  return @result;
}


# Check that the queue directory passed in is flat and contains
# no queue sub-directories. For some MTA's this may be a no-op.
# For sendmail it matters a lot! Sendmail will put different files in
# different directories if there are subdirectories called things like
# qf, xf, tf or df. Also directories called q1, q2, etc. are a sure
# sign that sendmail is running queue groups, which MailScanner cannot
# handle.
#
# Called from main mailscanner script
#
sub CheckQueueIsFlat {
  my($dir) = @_;

  #MailScanner::Log::WarnLog("In CheckQueueIsFlat, dir is %s", $dir);
  my($dirhandle, $f);

  $dirhandle = new DirHandle;
  $dirhandle->open($dir)
    or MailScanner::Log::DieLog("Cannot read queue directory $dir");

  # Check there are no q\d or qf subdirectories
  while($f = $dirhandle->read()) {
    # 2nd half of the line for SuSE Linux setups which put .hoststat
    # directory inside the queue!
    next if $f =~ /^\.\.?$/ || $f =~ /^\.hoststat/;
    # Delete core files
    $f =~ /^core$/ and unlink "core";
    next unless $f =~ /^q[0-9f]$/;
    # Also needs untaint... sledgehammer. nut.
    $f =~ /(.*)/;
    MailScanner::Log::DieLog("Queue directory %s cannot contain sub-" .
                             "directories, currently contains dir %s",
                             $dir, $1)
      if -d "$dir/$1";
  }
  $dirhandle->close();

  return 1;
}

1;
