+sub prurl {
+ my ($env, $u) = @_;
+ index($u, '//') == 0 ? "$env->{'psgi.url_scheme'}:$u" : $u;
+}
+
+# for misguided people who believe in this stuff, give them a
+# substitution for '.'
+# ․ · and ͺ were also candidates:
+# https://public-inbox.org/meta/20170615015250.GA6484@starla/
+# However, • was chosen to make copy+paste errors more obvious
+sub obfuscate_addrs ($$;$) {
+ my $ibx = $_[0];
+ my $repl = $_[2] || '•';
+ my $re = $ibx->{-no_obfuscate_re}; # regex of domains
+ my $addrs = $ibx->{-no_obfuscate}; # { adddress => 1 }
+ $_[1] =~ s/(([\w\.\+=\-]+)\@([\w\-]+\.[\w\.\-]+))/
+ my ($addr, $user, $domain) = ($1, $2, $3);
+ if ($addrs->{$addr} || ((defined $re && $domain =~ $re))) {
+ $addr;
+ } else {
+ $domain =~ s!([^\.]+)\.!$1$repl!;
+ $user . '@' . $domain
+ }
+ /sge;
+}
+
+# like format_sanitized_subject in git.git pretty.c with '%f' format string
+sub to_filename ($) {
+ my ($s, undef) = split(/\n/, $_[0]);
+ $s =~ s/[^A-Za-z0-9_\.]+/-/g;
+ $s =~ tr/././s;
+ $s =~ s/[\.\-]+\z//;
+ $s =~ s/\A[\.\-]+//;
+ $s
+}
+
+# convert a filename (or any string) to HTML attribute
+
+my %ESCAPES = map { chr($_) => sprintf('::%02x', $_) } (0..255);
+$ESCAPES{'/'} = ':'; # common
+
+sub to_attr ($) {
+ my ($str) = @_;
+
+ # git would never do this to us:
+ return if index($str, '//') >= 0;
+
+ my $first = '';
+ if ($str =~ s/\A([^A-Ya-z])//ms) { # start with a letter
+ $first = sprintf('Z%02x', ord($1));
+ }
+ $str =~ s/([^A-Za-z0-9_\.\-])/$ESCAPES{$1}/egms;
+ $first . $str;
+}
+
+# reverse the result of to_attr
+sub from_attr ($) {
+ my ($str) = @_;
+ my $first = '';
+ if ($str =~ s/\AZ([a-f0-9]{2})//ms) {
+ $first = chr(hex($1));
+ }
+ $str =~ s!::([a-f0-9]{2})!chr(hex($1))!egms;
+ $str =~ tr!:!/!;
+ $first . $str;
+}
+