# Copyright (C) 2020-2021 all contributors
# License: AGPL-3.0+
# Writes PublicInbox::Eml objects atomically to a mbox variant or Maildir
package PublicInbox::LeiToMail;
use strict;
use v5.10.1;
use parent qw(PublicInbox::IPC);
use PublicInbox::Eml;
use PublicInbox::Lock;
use PublicInbox::ProcessPipe;
use PublicInbox::Spawn qw(which spawn popen_rd);
use PublicInbox::LeiDedupe;
use PublicInbox::OnDestroy;
use Symbol qw(gensym);
use IO::Handle; # ->autoflush
use Fcntl qw(SEEK_SET SEEK_END O_CREAT O_EXCL O_WRONLY);
use Errno qw(EEXIST ESPIPE ENOENT);
use PublicInbox::Git;
my %kw2char = ( # Maildir characters
draft => 'D',
flagged => 'F',
answered => 'R',
seen => 'S'
);
my %kw2status = (
flagged => [ 'X-Status' => 'F' ],
answered => [ 'X-Status' => 'A' ],
seen => [ 'Status' => 'R' ],
draft => [ 'X-Status' => 'T' ],
);
sub _mbox_hdr_buf ($$$) {
my ($eml, $type, $smsg) = @_;
$eml->header_set($_) for (qw(Lines Bytes Content-Length));
# Messages are always 'O' (non-\Recent in IMAP), it saves
# MUAs the trouble of rewriting the mbox if no other
# changes are made
my %hdr = (Status => [ 'O' ]); # set Status, X-Status
for my $k (@{$smsg->{kw} // []}) {
if (my $ent = $kw2status{$k}) {
push @{$hdr{$ent->[0]}}, $ent->[1];
} else { # X-Label?
warn "TODO: keyword `$k' not supported for mbox\n";
}
}
while (my ($name, $chars) = each %hdr) {
$eml->header_set($name, join('', sort @$chars));
}
my $buf = delete $eml->{hdr};
# fixup old bug from import (pre-a0c07cba0e5d8b6a)
$$buf =~ s/\A[\r\n]*From [^\r\n]*\r?\n//s;
my $ident = $smsg->{blob} // 'lei';
if (defined(my $pct = $smsg->{pct})) { $ident .= "=$pct" }
substr($$buf, 0, 0, # prepend From line
"From $ident\@$type Thu Jan 1 00:00:00 1970$eml->{crlf}");
$buf;
}
sub atomic_append { # for on-disk destinations (O_APPEND, or O_EXCL)
my ($fh, $buf) = @_;
defined(my $w = syswrite($fh, $$buf)) or die "write: $!";
$w == length($$buf) or die "short write: $w != ".length($$buf);
}
sub _print_full {
my ($fh, $buf) = @_;
print $fh $$buf or die "print: $!";
}
sub eml2mboxrd ($;$) {
my ($eml, $smsg) = @_;
my $buf = _mbox_hdr_buf($eml, 'mboxrd', $smsg);
if (my $bdy = delete $eml->{bdy}) {
$$bdy =~ s/^(>*From )/>$1/gm;
$$buf .= $eml->{crlf};
substr($$bdy, 0, 0, $$buf); # prepend header
$buf = $bdy;
}
$$buf .= $eml->{crlf};
$buf;
}
sub eml2mboxo {
my ($eml, $smsg) = @_;
my $buf = _mbox_hdr_buf($eml, 'mboxo', $smsg);
if (my $bdy = delete $eml->{bdy}) {
$$bdy =~ s/^From />From /gm;
$$buf .= $eml->{crlf};
substr($$bdy, 0, 0, $$buf); # prepend header
$buf = $bdy;
}
$$buf .= $eml->{crlf};
$buf;
}
sub _mboxcl_common ($$$) {
my ($buf, $bdy, $crlf) = @_;
# add Lines: so mutt won't have to add it on MUA close
my $lines = $$bdy =~ tr!\n!\n!;
$$buf .= 'Content-Length: '.length($$bdy).$crlf.
'Lines: '.$lines.$crlf.$crlf;
substr($$bdy, 0, 0, $$buf); # prepend header
$_[0] = $bdy;
}
# mboxcl still escapes "From " lines
sub eml2mboxcl {
my ($eml, $smsg) = @_;
my $buf = _mbox_hdr_buf($eml, 'mboxcl', $smsg);
my $crlf = $eml->{crlf};
if (my $bdy = delete $eml->{bdy}) {
$$bdy =~ s/^From />From /gm;
_mboxcl_common($buf, $bdy, $crlf);
}
$$buf .= $crlf;
$buf;
}
# mboxcl2 has no "From " escaping
sub eml2mboxcl2 {
my ($eml, $smsg) = @_;
my $buf = _mbox_hdr_buf($eml, 'mboxcl2', $smsg);
my $crlf = $eml->{crlf};
if (my $bdy = delete $eml->{bdy}) {
_mboxcl_common($buf, $bdy, $crlf);
}
$$buf .= $crlf;
$buf;
}
sub git_to_mail { # git->cat_async callback
my ($bref, $oid, $type, $size, $arg) = @_;
if ($type ne 'blob') {
if ($type eq 'missing') {
warn "missing $oid\n";
} else {
warn "unexpected type=$type for $oid\n";
}
}
my ($write_cb, $smsg) = @$arg;
if ($smsg->{blob} ne $oid) {
die "BUG: expected=$smsg->{blob} got=$oid";
}
$write_cb->($bref, $smsg) if $size > 0;
}
sub reap_compress { # dwaitpid callback
my ($lei, $pid) = @_;
my $cmd = delete $lei->{"pid.$pid"};
return if $? == 0;
$lei->fail("@$cmd failed", $? >> 8);
}
# all of these support -c for stdout and -d for decompression,
# mutt is commonly distributed with hooks for gz, bz2 and xz, at least
# { foo => '' } means "--foo" is passed to the command-line,
# otherwise { foo => '--bar' } passes "--bar"
our %zsfx2cmd = (
gz => [ qw(GZIP pigz gzip), { rsyncable => '', threads => '-p' } ],
bz2 => [ 'bzip2', {} ],
xz => [ 'xz', { threads => '-T' } ],
# XXX does anybody care for these? I prefer zstd on entire FSes,
# so it's probably not necessary on a per-file basis
# zst => [ 'zstd', { -default => [ qw(-q) ], # it's noisy by default
# rsyncable => '', threads => '-T' } ],
# zz => [ 'pigz', { -default => [ '--zlib' ],
# rsyncable => '', threads => '-p' }],
# lzo => [ 'lzop', {} ],
# lzma => [ 'lzma', {} ],
);
sub zsfx2cmd ($$$) {
my ($zsfx, $decompress, $lei) = @_;
my $x = $zsfx2cmd{$zsfx} // die "no support for suffix=.$zsfx";
my @info = @$x;
my $cmd_opt = pop @info;
my @cmd = (undef, $decompress ? qw(-dc) : qw(-c));
for my $exe (@info) {
# I think respecting client's ENV{GZIP} is OK, not sure
# about ENV overrides for other, less-common compressors
if ($exe eq uc($exe)) {
$exe = $lei->{env}->{$exe} or next;
}
$cmd[0] = which($exe) and last;
}
$cmd[0] // die join(' or ', @info)." missing for .$zsfx";
# push @cmd, @{$cmd_opt->{-default}} if $cmd_opt->{-default};
for my $bool (qw(rsyncable)) {
my $switch = $cmd_opt->{rsyncable} // next;
push @cmd, '--'.($switch || $bool);
}
for my $key (qw(threads)) { # support compression level?
my $switch = $cmd_opt->{$key} // next;
my $val = $lei->{opt}->{$key} // next;
push @cmd, $switch, $val;
}
\@cmd;
}
sub _post_augment_mbox { # open a compressor process
my ($self, $lei, $zpipe) = @_;
my $zsfx = $self->{zsfx} or return;
my $cmd = zsfx2cmd($zsfx, undef, $lei);
my ($r, $w) = splice(@$zpipe, 0, 2);
my $rdr = { 0 => $r, 1 => $lei->{1}, 2 => $lei->{2} };
my $pid = spawn($cmd, $lei->{env}, $rdr);
my $pp = gensym;
my $dup = bless { "pid.$pid" => $cmd }, ref($lei);
$dup->{$_} = $lei->{$_} for qw(2 sock);
tie *$pp, 'PublicInbox::ProcessPipe', $pid, $w, \&reap_compress, $dup;
$lei->{1} = $pp;
die 'BUG: unexpected {ovv}->{lock_path}' if $lei->{ovv}->{lock_path};
$lei->{ovv}->ovv_out_lk_init;
}
sub decompress_src ($$$) {
my ($in, $zsfx, $lei) = @_;
my $cmd = zsfx2cmd($zsfx, 1, $lei);
popen_rd($cmd, $lei->{env}, { 0 => $in, 2 => $lei->{2} });
}
sub dup_src ($) {
my ($in) = @_;
# fileno needed because wq_set_recv_modes only used ">&=" for {1}
# and Perl blindly trusts that to reject the '+' (readability flag)
open my $dup, '+>>&=', fileno($in) or die "dup: $!";
$dup;
}
# --augment existing output destination, with deduplication
sub _augment { # MboxReader eml_cb
my ($eml, $lei) = @_;
# ignore return value, just populate the skv
$lei->{dedupe}->is_dup($eml);
}
sub _mbox_write_cb ($$) {
my ($self, $lei) = @_;
my $ovv = $lei->{ovv};
my $m = 'eml2'.$ovv->{fmt};
my $eml2mbox = $self->can($m) or die "$self->$m missing";
my $out = $lei->{1} // die "no stdout ($m, $ovv->{dst})"; # redirected earlier
$out->autoflush(1);
my $write = $ovv->{lock_path} ? \&_print_full : \&atomic_append;
my $dedupe = $lei->{dedupe};
$dedupe->prepare_dedupe;
sub { # for git_to_mail
my ($buf, $smsg, $eml) = @_;
return unless $out;
$eml //= PublicInbox::Eml->new($buf);
if (!$dedupe->is_dup($eml, $smsg->{blob})) {
$buf = $eml2mbox->($eml, $smsg);
my $lk = $ovv->lock_for_scope;
eval { $write->($out, $buf) };
if ($@) {
die $@ if ref($@) ne 'PublicInbox::SIGPIPE';
undef $out
}
}
}
}
sub _maildir_each_file ($$;@) {
my ($dir, $cb, @arg) = @_;
for my $d (qw(new/ cur/)) {
my $pfx = $dir.$d;
opendir my $dh, $pfx or next;
while (defined(my $fn = readdir($dh))) {
$cb->($pfx.$fn, @arg) if $fn =~ /:2,[A-Za-z]*\z/;
}
}
}
sub _augment_file { # _maildir_each_file cb
my ($f, $lei) = @_;
my $eml = PublicInbox::InboxWritable::eml_from_path($f) or return;
_augment($eml, $lei);
}
# _maildir_each_file callback, \&CORE::unlink doesn't work with it
sub _unlink { unlink($_[0]) }
sub _rand () {
state $seq = 0;
sprintf('%x,%x,%x,%x', rand(0xffffffff), time, $$, ++$seq);
}
sub _buf2maildir {
my ($dst, $buf, $smsg) = @_;
my $kw = $smsg->{kw} // [];
my $sfx = join('', sort(map { $kw2char{$_} // () } @$kw));
my $rand = ''; # chosen by die roll :P
my ($tmp, $fh, $final);
my $common = $smsg->{blob} // _rand;
if (defined(my $pct = $smsg->{pct})) { $common .= "=$pct" }
do {
$tmp = $dst.'tmp/'.$rand.$common;
} while (!sysopen($fh, $tmp, O_CREAT|O_EXCL|O_WRONLY) &&
$! == EEXIST && ($rand = _rand.','));
if (print $fh $$buf and close($fh)) {
# ignore new/ and write only to cur/, otherwise MUAs
# with R/W access to the Maildir will end up doing
# a mass rename which can take a while with thousands
# of messages.
$dst .= 'cur/';
$rand = '';
do {
$final = $dst.$rand.$common.':2,'.$sfx;
} while (!link($tmp, $final) && $! == EEXIST &&
($rand = _rand.','));
unlink($tmp) or warn "W: failed to unlink $tmp: $!\n";
} else {
my $err = $!;
unlink($tmp);
die "Error writing $smsg->{blob} to $dst: $err";
}
}
sub _maildir_write_cb ($$) {
my ($self, $lei) = @_;
my $dedupe = $lei->{dedupe};
$dedupe->prepare_dedupe;
my $dst = $lei->{ovv}->{dst};
sub { # for git_to_mail
my ($buf, $smsg, $eml) = @_;
$buf //= \($eml->as_string);
return _buf2maildir($dst, $buf, $smsg) if !$dedupe;
$eml //= PublicInbox::Eml->new($$buf); # copy buf
return if $dedupe->is_dup($eml, $smsg->{blob});
undef $eml;
_buf2maildir($dst, $buf, $smsg);
}
}
sub write_cb { # returns a callback for git_to_mail
my ($self, $lei) = @_;
# _mbox_write_cb or _maildir_write_cb
my $m = "_$self->{base_type}_write_cb";
$self->$m($lei);
}
sub new {
my ($cls, $lei) = @_;
my $fmt = $lei->{ovv}->{fmt};
my $dst = $lei->{ovv}->{dst};
my $self = bless {}, $cls;
if ($fmt eq 'maildir') {
$self->{base_type} = 'maildir';
-e $dst && !-d _ and die
"$dst exists and is not a directory\n";
$lei->{ovv}->{dst} = $dst .= '/' if substr($dst, -1) ne '/';
} elsif (substr($fmt, 0, 4) eq 'mbox') {
(-d $dst || (-e _ && !-w _)) and die
"$dst exists and is not a writable file\n";
$self->can("eml2$fmt") or die "bad mbox --format=$fmt\n";
$self->{base_type} = 'mbox';
} else {
die "bad mail --format=$fmt\n";
}
$lei->{dedupe} = PublicInbox::LeiDedupe->new($lei);
$self;
}
sub _pre_augment_maildir {} # noop
sub _do_augment_maildir {
my ($self, $lei) = @_;
my $dst = $lei->{ovv}->{dst};
if ($lei->{opt}->{augment}) {
my $dedupe = $lei->{dedupe};
if ($dedupe && $dedupe->prepare_dedupe) {
require PublicInbox::InboxWritable; # eml_from_path
_maildir_each_file($dst, \&_augment_file, $lei);
$dedupe->pause_dedupe;
}
} else { # clobber existing Maildir
_maildir_each_file($dst, \&_unlink);
}
}
sub _post_augment_maildir {
my ($self, $lei) = @_;
my $dst = $lei->{ovv}->{dst};
for my $x (qw(tmp new cur)) {
my $d = $dst.$x;
next if -d $d;
require File::Path;
File::Path::mkpath($d);
-d $d or die "$d is not a directory";
}
}
sub _pre_augment_mbox {
my ($self, $lei) = @_;
my $dst = $lei->{ovv}->{dst};
if ($dst ne '/dev/stdout') {
my $mode = -p $dst ? '>' : '+>>';
if (-f _ && !$lei->{opt}->{augment} and !unlink($dst)) {
$! == ENOENT or die "unlink($dst): $!";
}
open my $out, $mode, $dst or die "open($dst): $!";
$lei->{1} = $out;
}
# Perl does SEEK_END even with O_APPEND :<
$self->{seekable} = seek($lei->{1}, 0, SEEK_SET);
if (!$self->{seekable} && $! != ESPIPE && $dst ne '/dev/stdout') {
die "seek($dst): $!\n";
}
state $zsfx_allow = join('|', keys %zsfx2cmd);
($self->{zsfx}) = ($dst =~ /\.($zsfx_allow)\z/) or return;
pipe(my ($r, $w)) or die "pipe: $!";
[ $r, $w ];
}
sub _do_augment_mbox {
my ($self, $lei) = @_;
return if !$lei->{opt}->{augment};
my $dedupe = $lei->{dedupe};
my $dst = $lei->{ovv}->{dst};
die "cannot augment $dst, not seekable\n" if !$self->{seekable};
my $out = $lei->{1};
if (-s $out && $dedupe && $dedupe->prepare_dedupe) {
my $zsfx = $self->{zsfx};
my $rd = $zsfx ? decompress_src($out, $zsfx, $lei) :
dup_src($out);
my $fmt = $lei->{ovv}->{fmt};
require PublicInbox::MboxReader;
PublicInbox::MboxReader->$fmt($rd, \&_augment, $lei);
}
# maybe some systems don't honor O_APPEND, Perl does this:
seek($out, 0, SEEK_END) or die "seek $dst: $!";
$dedupe->pause_dedupe if $dedupe;
}
sub pre_augment { # fast (1 disk seek), runs in main daemon
my ($self, $lei) = @_;
# _pre_augment_maildir, _pre_augment_mbox
my $m = "_pre_augment_$self->{base_type}";
$self->$m($lei);
}
sub do_augment { # slow, runs in wq worker
my ($self, $lei) = @_;
# _do_augment_maildir, _do_augment_mbox
my $m = "_do_augment_$self->{base_type}";
$self->$m($lei);
}
sub post_augment { # fast (spawn compressor or mkdir), runs in main daemon
my ($self, $lei, @args) = @_;
# _post_augment_maildir, _post_augment_mbox
my $m = "_post_augment_$self->{base_type}";
$self->$m($lei, @args);
}
sub write_mail { # via ->wq_do
my ($self, $git_dir, $smsg, $lei) = @_;
my $not_done = delete $self->{4}; # write end of {each_smsg_done}
my $wcb = $self->{wcb} //= do { # first message
my %sig = $lei->atfork_child_wq($self);
@SIG{keys %sig} = values %sig; # not local
$lei->{dedupe}->prepare_dedupe;
$self->write_cb($lei);
};
my $git = $self->{"$$\0$git_dir"} //= PublicInbox::Git->new($git_dir);
$git->cat_async($smsg->{blob}, \&git_to_mail, [$wcb, $smsg, $not_done]);
}
sub ipc_atfork_prepare {
my ($self) = @_;
# (done_wr, stdout|mbox, stderr, 3: sock, 4: each_smsg_done_wr)
$self->wq_set_recv_modes(qw[+<&= >&= >&= +<&= >&=]);
$self->SUPER::ipc_atfork_prepare; # PublicInbox::IPC
}
# We rely on OnDestroy to run this before ->DESTROY, since ->DESTROY
# ordering is unstable at worker exit and may cause segfaults
sub reap_gits {
my ($self) = @_;
for my $git (delete @$self{grep(/\A$$\0/, keys %$self)}) {
$git->async_wait_all;
}
}
sub ipc_atfork_child { # runs after IPC::wq_worker_loop
my ($self) = @_;
$self->SUPER::ipc_atfork_child;
# reap_gits needs to run before $self->DESTROY,
# IPC.pm will ensure that.
PublicInbox::OnDestroy->new($$, \&reap_gits, $self);
}
1;