treewide: run update-copyrights from gnulib for 2019

[public-inbox.git] / lib / PublicInbox / MsgIter.pm

diff --git a/lib/PublicInbox/MsgIter.pm b/lib/PublicInbox/MsgIter.pm
index 5be06a44be16dc96d064aa7b3eefbaff8e021f97..6c18d2bf3102c56e070d8a1ff8dbce44b47e847d 100644 (file)
--- a/lib/PublicInbox/MsgIter.pm
+++ b/lib/PublicInbox/MsgIter.pm
@@ -1,20 +1,22 @@
-# Copyright (C) 2016 all contributors <meta@public-inbox.org>
+# Copyright (C) 2016-2020 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
-#
+
+# read-only utilities for Email::MIME
 package PublicInbox::MsgIter;
 use strict;
 use warnings;
 use base qw(Exporter);
-our @EXPORT = qw(msg_iter);
+our @EXPORT = qw(msg_iter msg_part_text);
 use PublicInbox::MIME;
 
 # Like Email::MIME::walk_parts, but this is:
 # * non-recursive
 # * passes depth and indices to the iterator callback
-sub msg_iter ($$) {
-       my ($mime, $cb) = @_;
+sub msg_iter ($$;$$) {
+       my ($mime, $cb, $cb_arg, $do_undef) = @_;
        my @parts = $mime->subparts;
        if (@parts) {
+               $mime = $_[0] = undef if $do_undef; # saves some memory
                my $i = 0;
                @parts = map { [ $_, 1, ++$i ] } @parts;
                while (my $p = shift @parts) {
@@ -26,12 +28,47 @@ sub msg_iter ($$) {
                                @sub = map { [ $_, $depth, @idx, ++$i ] } @sub;
                                @parts = (@sub, @parts);
                        } else {
-                               $cb->($p);
+                               $cb->($p, $cb_arg);
                        }
                }
        } else {
-               $cb->([$mime, 0, 0]);
+               $cb->([$mime, 0, 0], $cb_arg);
+       }
+}
+
+sub msg_part_text ($$) {
+       my ($part, $ct) = @_;
+
+       # TODO: we may offer a separate sub for people who need to index
+       # HTML-only mail, but the majority of HTML mail is multipart/alternative
+       # with a text part which we don't have to waste cycles decoding
+       return if $ct =~ m!\btext/x?html\b!;
+
+       my $s = eval { $part->body_str };
+       my $err = $@;
+
+       # text/plain is the default, multipart/mixed happened a few
+       # times when it should not have been:
+       #   <87llgalspt.fsf@free.fr>
+       #   <200308111450.h7BEoOu20077@mail.osdl.org>
+       if ($err && ($ct =~ m!\btext/\b!i ||
+                       $ct =~ m!\bmultipart/mixed\b!i)) {
+               my $cte = $part->header_raw('Content-Transfer-Encoding');
+               if (defined($cte) && $cte =~ /\b7bit\b/i) {
+                       $s = $part->body;
+                       $err = undef if $s =~ /\A[[:ascii:]]+\z/s;
+               } else {
+                       # Try to assume UTF-8 because Alpine seems to
+                       # do wacky things and set charset=X-UNKNOWN
+                       $part->charset_set('UTF-8');
+                       $s = eval { $part->body_str };
+               }
+
+               # If forcing charset=UTF-8 failed,
+               # caller will warn further down...
+               $s = $part->body if $@;
        }
+       ($s, $err);
 }
 
 1;