contrib / contacts / git-contactson commit contacts: gather all blame sources prior to invoking git-blame (db8cae7)
   1#!/usr/bin/perl
   2
   3# List people who might be interested in a patch.  Useful as the argument to
   4# git-send-email --cc-cmd option, and in other situations.
   5#
   6# Usage: git contacts <file | rev-list option> ...
   7
   8use strict;
   9use warnings;
  10use IPC::Open2;
  11
  12my $since = '5-years-ago';
  13my $min_percent = 10;
  14my $labels_rx = qr/Signed-off-by|Reviewed-by|Acked-by|Cc/i;
  15my %seen;
  16
  17sub format_contact {
  18        my ($name, $email) = @_;
  19        return "$name <$email>";
  20}
  21
  22sub parse_commit {
  23        my ($commit, $data) = @_;
  24        my $contacts = $commit->{contacts};
  25        my $inbody = 0;
  26        for (split(/^/m, $data)) {
  27                if (not $inbody) {
  28                        if (/^author ([^<>]+) <(\S+)> .+$/) {
  29                                $contacts->{format_contact($1, $2)} = 1;
  30                        } elsif (/^$/) {
  31                                $inbody = 1;
  32                        }
  33                } elsif (/^$labels_rx:\s+([^<>]+)\s+<(\S+?)>$/o) {
  34                        $contacts->{format_contact($1, $2)} = 1;
  35                }
  36        }
  37}
  38
  39sub import_commits {
  40        my ($commits) = @_;
  41        return unless %$commits;
  42        my $pid = open2 my $reader, my $writer, qw(git cat-file --batch);
  43        for my $id (keys(%$commits)) {
  44                print $writer "$id\n";
  45                my $line = <$reader>;
  46                if ($line =~ /^([0-9a-f]{40}) commit (\d+)/) {
  47                        my ($cid, $len) = ($1, $2);
  48                        die "expected $id but got $cid\n" unless $id eq $cid;
  49                        my $data;
  50                        # cat-file emits newline after data, so read len+1
  51                        read $reader, $data, $len + 1;
  52                        parse_commit($commits->{$id}, $data);
  53                }
  54        }
  55        close $reader;
  56        close $writer;
  57        waitpid($pid, 0);
  58        die "git-cat-file error: $?\n" if $?;
  59}
  60
  61sub get_blame {
  62        my ($commits, $source, $start, $len, $from) = @_;
  63        open my $f, '-|',
  64                qw(git blame --porcelain -C), '-L', "$start,+$len",
  65                '--since', $since, "$from^", '--', $source or die;
  66        while (<$f>) {
  67                if (/^([0-9a-f]{40}) \d+ \d+ \d+$/) {
  68                        my $id = $1;
  69                        $commits->{$id} = { id => $id, contacts => {} }
  70                                unless $seen{$id};
  71                        $seen{$id} = 1;
  72                }
  73        }
  74        close $f;
  75}
  76
  77sub blame_sources {
  78        my ($sources, $commits) = @_;
  79        for my $s (keys %$sources) {
  80                for my $id (keys %{$sources->{$s}}) {
  81                        for my $range (@{$sources->{$s}{$id}}) {
  82                                get_blame($commits, $s,
  83                                          $range->[0], $range->[1], $id);
  84                        }
  85                }
  86        }
  87}
  88
  89sub scan_patches {
  90        my ($sources, $id, $f) = @_;
  91        my $source;
  92        while (<$f>) {
  93                if (/^From ([0-9a-f]{40}) Mon Sep 17 00:00:00 2001$/) {
  94                        $id = $1;
  95                        $seen{$id} = 1;
  96                }
  97                next unless $id;
  98                if (m{^--- (?:a/(.+)|/dev/null)$}) {
  99                        $source = $1;
 100                } elsif (/^--- /) {
 101                        die "Cannot parse hunk source: $_\n";
 102                } elsif (/^@@ -(\d+)(?:,(\d+))?/ && $source) {
 103                        my $len = defined($2) ? $2 : 1;
 104                        push @{$sources->{$source}{$id}}, [$1, $len] if $len;
 105                }
 106        }
 107}
 108
 109sub scan_patch_file {
 110        my ($commits, $file) = @_;
 111        open my $f, '<', $file or die "read failure: $file: $!\n";
 112        scan_patches($commits, undef, $f);
 113        close $f;
 114}
 115
 116sub parse_rev_args {
 117        my @args = @_;
 118        open my $f, '-|',
 119                qw(git rev-parse --revs-only --default HEAD --symbolic), @args
 120                or die;
 121        my @revs;
 122        while (<$f>) {
 123                chomp;
 124                push @revs, $_;
 125        }
 126        close $f;
 127        return @revs if scalar(@revs) != 1;
 128        return "^$revs[0]", 'HEAD' unless $revs[0] =~ /^-/;
 129        return $revs[0], 'HEAD';
 130}
 131
 132sub scan_rev_args {
 133        my ($commits, $args) = @_;
 134        my @revs = parse_rev_args(@$args);
 135        open my $f, '-|', qw(git rev-list --reverse), @revs or die;
 136        while (<$f>) {
 137                chomp;
 138                my $id = $_;
 139                $seen{$id} = 1;
 140                open my $g, '-|', qw(git show -C --oneline), $id or die;
 141                scan_patches($commits, $id, $g);
 142                close $g;
 143        }
 144        close $f;
 145}
 146
 147sub mailmap_contacts {
 148        my ($contacts) = @_;
 149        my %mapped;
 150        my $pid = open2 my $reader, my $writer, qw(git check-mailmap --stdin);
 151        for my $contact (keys(%$contacts)) {
 152                print $writer "$contact\n";
 153                my $canonical = <$reader>;
 154                chomp $canonical;
 155                $mapped{$canonical} += $contacts->{$contact};
 156        }
 157        close $reader;
 158        close $writer;
 159        waitpid($pid, 0);
 160        die "git-check-mailmap error: $?\n" if $?;
 161        return \%mapped;
 162}
 163
 164if (!@ARGV) {
 165        die "No input revisions or patch files\n";
 166}
 167
 168my (@files, @rev_args);
 169for (@ARGV) {
 170        if (-e) {
 171                push @files, $_;
 172        } else {
 173                push @rev_args, $_;
 174        }
 175}
 176
 177my %sources;
 178for (@files) {
 179        scan_patch_file(\%sources, $_);
 180}
 181if (@rev_args) {
 182        scan_rev_args(\%sources, \@rev_args)
 183}
 184
 185my %commits;
 186blame_sources(\%sources, \%commits);
 187import_commits(\%commits);
 188
 189my $contacts = {};
 190for my $commit (values %commits) {
 191        for my $contact (keys %{$commit->{contacts}}) {
 192                $contacts->{$contact}++;
 193        }
 194}
 195$contacts = mailmap_contacts($contacts);
 196
 197my $ncommits = scalar(keys %commits);
 198for my $contact (keys %$contacts) {
 199        my $percent = $contacts->{$contact} * 100 / $ncommits;
 200        next if $percent < $min_percent;
 201        print "$contact\n";
 202}