Squashed 'third_party/git/' content from commit cb71568594

git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7

1 files changed, 203 insertions, 0 deletions

diff --git a/contrib/contacts/git-contacts b/contrib/contacts/git-contacts
new file mode 100755
index 000000000000..85ad732fc063
--- /dev/null
+++ b/contrib/contacts/git-contacts
@@ -0,0 +1,203 @@
+#!/usr/bin/perl
+
+# List people who might be interested in a patch.  Useful as the argument to
+# git-send-email --cc-cmd option, and in other situations.
+#
+# Usage: git contacts <file | rev-list option> ...
+
+use strict;
+use warnings;
+use IPC::Open2;
+
+my $since = '5-years-ago';
+my $min_percent = 10;
+my $labels_rx = qr/Signed-off-by|Reviewed-by|Acked-by|Cc|Reported-by/i;
+my %seen;
+
+sub format_contact {
+	my ($name, $email) = @_;
+	return "$name <$email>";
+}
+
+sub parse_commit {
+	my ($commit, $data) = @_;
+	my $contacts = $commit->{contacts};
+	my $inbody = 0;
+	for (split(/^/m, $data)) {
+		if (not $inbody) {
+			if (/^author ([^<>]+) <(\S+)> .+$/) {
+				$contacts->{format_contact($1, $2)} = 1;
+			} elsif (/^$/) {
+				$inbody = 1;
+			}
+		} elsif (/^$labels_rx:\s+([^<>]+)\s+<(\S+?)>$/o) {
+			$contacts->{format_contact($1, $2)} = 1;
+		}
+	}
+}
+
+sub import_commits {
+	my ($commits) = @_;
+	return unless %$commits;
+	my $pid = open2 my $reader, my $writer, qw(git cat-file --batch);
+	for my $id (keys(%$commits)) {
+		print $writer "$id\n";
+		my $line = <$reader>;
+		if ($line =~ /^([0-9a-f]{40}) commit (\d+)/) {
+			my ($cid, $len) = ($1, $2);
+			die "expected $id but got $cid\n" unless $id eq $cid;
+			my $data;
+			# cat-file emits newline after data, so read len+1
+			read $reader, $data, $len + 1;
+			parse_commit($commits->{$id}, $data);
+		}
+	}
+	close $reader;
+	close $writer;
+	waitpid($pid, 0);
+	die "git-cat-file error: $?\n" if $?;
+}
+
+sub get_blame {
+	my ($commits, $source, $from, $ranges) = @_;
+	return unless @$ranges;
+	open my $f, '-|',
+		qw(git blame --porcelain -C),
+		map({"-L$_->[0],+$_->[1]"} @$ranges),
+		'--since', $since, "$from^", '--', $source or die;
+	while (<$f>) {
+		if (/^([0-9a-f]{40}) \d+ \d+ \d+$/) {
+			my $id = $1;
+			$commits->{$id} = { id => $id, contacts => {} }
+				unless $seen{$id};
+			$seen{$id} = 1;
+		}
+	}
+	close $f;
+}
+
+sub blame_sources {
+	my ($sources, $commits) = @_;
+	for my $s (keys %$sources) {
+		for my $id (keys %{$sources->{$s}}) {
+			get_blame($commits, $s, $id, $sources->{$s}{$id});
+		}
+	}
+}
+
+sub scan_patches {
+	my ($sources, $id, $f) = @_;
+	my $source;
+	while (<$f>) {
+		if (/^From ([0-9a-f]{40}) Mon Sep 17 00:00:00 2001$/) {
+			$id = $1;
+			$seen{$id} = 1;
+		}
+		next unless $id;
+		if (m{^--- (?:a/(.+)|/dev/null)$}) {
+			$source = $1;
+		} elsif (/^@@ -(\d+)(?:,(\d+))?/ && $source) {
+			my $len = defined($2) ? $2 : 1;
+			push @{$sources->{$source}{$id}}, [$1, $len] if $len;
+		}
+	}
+}
+
+sub scan_patch_file {
+	my ($commits, $file) = @_;
+	open my $f, '<', $file or die "read failure: $file: $!\n";
+	scan_patches($commits, undef, $f);
+	close $f;
+}
+
+sub parse_rev_args {
+	my @args = @_;
+	open my $f, '-|',
+		qw(git rev-parse --revs-only --default HEAD --symbolic), @args
+		or die;
+	my @revs;
+	while (<$f>) {
+		chomp;
+		push @revs, $_;
+	}
+	close $f;
+	return @revs if scalar(@revs) != 1;
+	return "^$revs[0]", 'HEAD' unless $revs[0] =~ /^-/;
+	return $revs[0], 'HEAD';
+}
+
+sub scan_rev_args {
+	my ($commits, $args) = @_;
+	my @revs = parse_rev_args(@$args);
+	open my $f, '-|', qw(git rev-list --reverse), @revs or die;
+	while (<$f>) {
+		chomp;
+		my $id = $_;
+		$seen{$id} = 1;
+		open my $g, '-|', qw(git show -C --oneline), $id or die;
+		scan_patches($commits, $id, $g);
+		close $g;
+	}
+	close $f;
+}
+
+sub mailmap_contacts {
+	my ($contacts) = @_;
+	my %mapped;
+	my $pid = open2 my $reader, my $writer, qw(git check-mailmap --stdin);
+	for my $contact (keys(%$contacts)) {
+		print $writer "$contact\n";
+		my $canonical = <$reader>;
+		chomp $canonical;
+		$mapped{$canonical} += $contacts->{$contact};
+	}
+	close $reader;
+	close $writer;
+	waitpid($pid, 0);
+	die "git-check-mailmap error: $?\n" if $?;
+	return \%mapped;
+}
+
+if (!@ARGV) {
+	die "No input revisions or patch files\n";
+}
+
+my (@files, @rev_args);
+for (@ARGV) {
+	if (-e) {
+		push @files, $_;
+	} else {
+		push @rev_args, $_;
+	}
+}
+
+my %sources;
+for (@files) {
+	scan_patch_file(\%sources, $_);
+}
+if (@rev_args) {
+	scan_rev_args(\%sources, \@rev_args)
+}
+
+my $toplevel = `git rev-parse --show-toplevel`;
+chomp $toplevel;
+chdir($toplevel) or die "chdir failure: $toplevel: $!\n";
+
+my %commits;
+blame_sources(\%sources, \%commits);
+import_commits(\%commits);
+
+my $contacts = {};
+for my $commit (values %commits) {
+	for my $contact (keys %{$commit->{contacts}}) {
+		$contacts->{$contact}++;
+	}
+}
+$contacts = mailmap_contacts($contacts);
+
+my $ncommits = scalar(keys %commits);
+for my $contact (keys %$contacts) {
+	my $percent = $contacts->{$contact} * 100 / $ncommits;
+	next if $percent < $min_percent;
+	print "$contact\n";
+}