[bpt/guile.git] / build-aux / gitlog-to-changelog

eval '(exit $?0)' && eval 'exec perl -wS "$0" ${1+"$@"}'
  & eval 'exec perl -wS "$0" $argv:q'
    if 0;
# Convert git log output to ChangeLog format.

my $VERSION = '2012-07-29 06:11'; # UTC
# The definition above must lie within the first 8 lines in order
# for the Emacs time-stamp write hook (at end) to update it.
# If you change this file with Emacs, please let the write hook
# do its job.  Otherwise, update this string manually.

# Copyright (C) 2008-2014 Free Software Foundation, Inc.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Written by Jim Meyering

use strict;
use warnings;
use Getopt::Long;
use POSIX qw(strftime);

(my $ME = $0) =~ s|.*/||;

# use File::Coda; # http://meyering.net/code/Coda/
END {
  defined fileno STDOUT or return;
  close STDOUT and return;
  warn "$ME: failed to close standard output: $!\n";
  $? ||= 1;
}

sub usage ($)
{
  my ($exit_code) = @_;
  my $STREAM = ($exit_code == 0 ? *STDOUT : *STDERR);
  if ($exit_code != 0)
    {
      print $STREAM "Try '$ME --help' for more information.\n";
    }
  else
    {
      print $STREAM <<EOF;
Usage: $ME [OPTIONS] [ARGS]

Convert git log output to ChangeLog format.  If present, any ARGS
are passed to "git log".  To avoid ARGS being parsed as options to
$ME, they may be preceded by '--'.

OPTIONS:

   --amend=FILE FILE maps from an SHA1 to perl code (i.e., s/old/new/) that
                  makes a change to SHA1's commit log text or metadata.
   --append-dot append a dot to the first line of each commit message if
                  there is no other punctuation or blank at the end.
   --no-cluster never cluster commit messages under the same date/author
                  header; the default is to cluster adjacent commit messages
                  if their headers are the same and neither commit message
                  contains multiple paragraphs.
   --srcdir=DIR the root of the source tree, from which the .git/
                  directory can be derived.
   --since=DATE convert only the logs since DATE;
                  the default is to convert all log entries.
   --format=FMT set format string for commit subject and body;
                  see 'man git-log' for the list of format metacharacters;
                  the default is '%s%n%b%n'
   --strip-tab  remove one additional leading TAB from commit message lines.
   --strip-cherry-pick  remove data inserted by "git cherry-pick";
                  this includes the "cherry picked from commit ..." line,
                  and the possible final "Conflicts:" paragraph.
   --help       display this help and exit
   --version    output version information and exit

EXAMPLE:

  $ME --since=2008-01-01 > ChangeLog
  $ME -- -n 5 foo > last-5-commits-to-branch-foo

SPECIAL SYNTAX:

The following types of strings are interpreted specially when they appear
at the beginning of a log message line.  They are not copied to the output.

  Copyright-paperwork-exempt: Yes
    Append the "(tiny change)" notation to the usual "date name email"
    ChangeLog header to mark a change that does not require a copyright
    assignment.
  Co-authored-by: Joe User <user\@example.com>
    List the specified name and email address on a second
    ChangeLog header, denoting a co-author.
  Signed-off-by: Joe User <user\@example.com>
    These lines are simply elided.

In a FILE specified via --amend, comment lines (starting with "#") are ignored.
FILE must consist of <SHA,CODE+> pairs where SHA is a 40-byte SHA1 (alone on
a line) referring to a commit in the current project, and CODE refers to one
or more consecutive lines of Perl code.  Pairs must be separated by one or
more blank line.

Here is sample input for use with --amend=FILE, from coreutils:

3a169f4c5d9159283548178668d2fae6fced3030
# fix typo in title:
s/all tile types/all file types/

1379ed974f1fa39b12e2ffab18b3f7a607082202
# Due to a bug in vc-dwim, I mis-attributed a patch by Paul to myself.
# Change the author to be Paul.  Note the escaped "@":
s,Jim .*>,Paul Eggert <eggert\\\@cs.ucla.edu>,

EOF
    }
  exit $exit_code;
}

# If the string $S is a well-behaved file name, simply return it.
# If it contains white space, quotes, etc., quote it, and return the new string.
sub shell_quote($)
{
  my ($s) = @_;
  if ($s =~ m![^\w+/.,-]!)
    {
      # Convert each single quote to '\''
      $s =~ s/\'/\'\\\'\'/g;
      # Then single quote the string.
      $s = "'$s'";
    }
  return $s;
}

sub quoted_cmd(@)
{
  return join (' ', map {shell_quote $_} @_);
}

# Parse file F.
# Comment lines (starting with "#") are ignored.
# F must consist of <SHA,CODE+> pairs where SHA is a 40-byte SHA1
# (alone on a line) referring to a commit in the current project, and
# CODE refers to one or more consecutive lines of Perl code.
# Pairs must be separated by one or more blank line.
sub parse_amend_file($)
{
  my ($f) = @_;

  open F, '<', $f
    or die "$ME: $f: failed to open for reading: $!\n";

  my $fail;
  my $h = {};
  my $in_code = 0;
  my $sha;
  while (defined (my $line = <F>))
    {
      $line =~ /^\#/
        and next;
      chomp $line;
      $line eq ''
        and $in_code = 0, next;

      if (!$in_code)
        {
          $line =~ /^([0-9a-fA-F]{40})$/
            or (warn "$ME: $f:$.: invalid line; expected an SHA1\n"),
              $fail = 1, next;
          $sha = lc $1;
          $in_code = 1;
          exists $h->{$sha}
            and (warn "$ME: $f:$.: duplicate SHA1\n"),
              $fail = 1, next;
        }
      else
        {
          $h->{$sha} ||= '';
          $h->{$sha} .= "$line\n";
        }
    }
  close F;

  $fail
    and exit 1;

  return $h;
}

# git_dir_option $SRCDIR
#
# From $SRCDIR, the --git-dir option to pass to git (none if $SRCDIR
# is undef).  Return as a list (0 or 1 element).
sub git_dir_option($)
{
  my ($srcdir) = @_;
  my @res = ();
  if (defined $srcdir)
    {
      my $qdir = shell_quote $srcdir;
      my $cmd = "cd $qdir && git rev-parse --show-toplevel";
      my $qcmd = shell_quote $cmd;
      my $git_dir = qx($cmd);
      defined $git_dir
        or die "$ME: cannot run $qcmd: $!\n";
      $? == 0
        or die "$ME: $qcmd had unexpected exit code or signal ($?)\n";
      chomp $git_dir;
      push @res, "--git-dir=$git_dir/.git";
    }
  @res;
}

{
  my $since_date;
  my $format_string = '%s%n%b%n';
  my $amend_file;
  my $append_dot = 0;
  my $cluster = 1;
  my $strip_tab = 0;
  my $strip_cherry_pick = 0;
  my $srcdir;
  GetOptions
    (
     help => sub { usage 0 },
     version => sub { print "$ME version $VERSION\n"; exit },
     'since=s' => \$since_date,
     'format=s' => \$format_string,
     'amend=s' => \$amend_file,
     'append-dot' => \$append_dot,
     'cluster!' => \$cluster,
     'strip-tab' => \$strip_tab,
     'strip-cherry-pick' => \$strip_cherry_pick,
     'srcdir=s' => \$srcdir,
    ) or usage 1;

  defined $since_date
    and unshift @ARGV, "--since=$since_date";

  # This is a hash that maps an SHA1 to perl code (i.e., s/old/new/)
  # that makes a correction in the log or attribution of that commit.
  my $amend_code = defined $amend_file ? parse_amend_file $amend_file : {};

  my @cmd = ('git',
             git_dir_option $srcdir,
             qw(log --log-size),
             '--pretty=format:%H:%ct  %an  <%ae>%n%n'.$format_string, @ARGV);
  open PIPE, '-|', @cmd
    or die ("$ME: failed to run '". quoted_cmd (@cmd) ."': $!\n"
            . "(Is your Git too old?  Version 1.5.1 or later is required.)\n");

  my $prev_multi_paragraph;
  my $prev_date_line = '';
  my @prev_coauthors = ();
  while (1)
    {
      defined (my $in = <PIPE>)
        or last;
      $in =~ /^log size (\d+)$/
        or die "$ME:$.: Invalid line (expected log size):\n$in";
      my $log_nbytes = $1;

      my $log;
      my $n_read = read PIPE, $log, $log_nbytes;
      $n_read == $log_nbytes
        or die "$ME:$.: unexpected EOF\n";

      # Extract leading hash.
      my ($sha, $rest) = split ':', $log, 2;
      defined $sha
        or die "$ME:$.: malformed log entry\n";
      $sha =~ /^[0-9a-fA-F]{40}$/
        or die "$ME:$.: invalid SHA1: $sha\n";

      # If this commit's log requires any transformation, do it now.
      my $code = $amend_code->{$sha};
      if (defined $code)
        {
          eval 'use Safe';
          my $s = new Safe;
          # Put the unpreprocessed entry into "$_".
          $_ = $rest;

          # Let $code operate on it, safely.
          my $r = $s->reval("$code")
            or die "$ME:$.:$sha: failed to eval \"$code\":\n$@\n";

          # Note that we've used this entry.
          delete $amend_code->{$sha};

          # Update $rest upon success.
          $rest = $_;
        }

      # Remove lines inserted by "git cherry-pick".
      if ($strip_cherry_pick)
        {
          $rest =~ s/^\s*Conflicts:\n.*//sm;
          $rest =~ s/^\s*\(cherry picked from commit [\da-f]+\)\n//m;
        }

      my @line = split "\n", $rest;
      my $author_line = shift @line;
      defined $author_line
        or die "$ME:$.: unexpected EOF\n";
      $author_line =~ /^(\d+)  (.*>)$/
        or die "$ME:$.: Invalid line "
          . "(expected date/author/email):\n$author_line\n";

      # Format 'Copyright-paperwork-exempt: Yes' as a standard ChangeLog
      # `(tiny change)' annotation.
      my $tiny = (grep (/^Copyright-paperwork-exempt:\s+[Yy]es$/, @line)
                  ? '  (tiny change)' : '');

      my $date_line = sprintf "%s  %s$tiny\n",
        strftime ("%F", localtime ($1)), $2;

      my @coauthors = grep /^Co-authored-by:.*$/, @line;
      # Omit meta-data lines we've already interpreted.
      @line = grep !/^(?:Signed-off-by:[ ].*>$
                       |Co-authored-by:[ ]
                       |Copyright-paperwork-exempt:[ ]
                       )/x, @line;

      # Remove leading and trailing blank lines.
      if (@line)
        {
          while ($line[0] =~ /^\s*$/) { shift @line; }
          while ($line[$#line] =~ /^\s*$/) { pop @line; }
        }

      # Record whether there are two or more paragraphs.
      my $multi_paragraph = grep /^\s*$/, @line;

      # Format 'Co-authored-by: A U Thor <email@example.com>' lines in
      # standard multi-author ChangeLog format.
      for (@coauthors)
        {
          s/^Co-authored-by:\s*/\t    /;
          s/\s*</  </;

          /<.*?@.*\..*>/
            or warn "$ME: warning: missing email address for "
              . substr ($_, 5) . "\n";
        }

      # If clustering of commit messages has been disabled, if this header
      # would be different from the previous date/name/email/coauthors header,
      # or if this or the previous entry consists of two or more paragraphs,
      # then print the header.
      if ( ! $cluster
          || $date_line ne $prev_date_line
          || "@coauthors" ne "@prev_coauthors"
          || $multi_paragraph
          || $prev_multi_paragraph)
        {
          $prev_date_line eq ''
            or print "\n";
          print $date_line;
          @coauthors
            and print join ("\n", @coauthors), "\n";
        }
      $prev_date_line = $date_line;
      @prev_coauthors = @coauthors;
      $prev_multi_paragraph = $multi_paragraph;

      # If there were any lines
      if (@line == 0)
        {
          warn "$ME: warning: empty commit message:\n  $date_line\n";
        }
      else
        {
          if ($append_dot)
            {
              # If the first line of the message has enough room, then
              if (length $line[0] < 72)
                {
                  # append a dot if there is no other punctuation or blank
                  # at the end.
                  $line[0] =~ /[[:punct:]\s]$/
                    or $line[0] .= '.';
                }
            }

          # Remove one additional leading TAB from each line.
          $strip_tab
            and map { s/^\t// } @line;

          # Prefix each non-empty line with a TAB.
          @line = map { length $_ ? "\t$_" : '' } @line;

          print "\n", join ("\n", @line), "\n";
        }

      defined ($in = <PIPE>)
        or last;
      $in ne "\n"
        and die "$ME:$.: unexpected line:\n$in";
    }

  close PIPE
    or die "$ME: error closing pipe from " . quoted_cmd (@cmd) . "\n";
  # FIXME-someday: include $PROCESS_STATUS in the diagnostic

  # Complain about any unused entry in the --amend=F specified file.
  my $fail = 0;
  foreach my $sha (keys %$amend_code)
    {
      warn "$ME:$amend_file: unused entry: $sha\n";
      $fail = 1;
    }

  exit $fail;
}

# Local Variables:
# mode: perl
# indent-tabs-mode: nil
# eval: (add-hook 'write-file-hooks 'time-stamp)
# time-stamp-start: "my $VERSION = '"
# time-stamp-format: "%:y-%02m-%02d %02H:%02M"
# time-stamp-time-zone: "UTC"
# time-stamp-end: "'; # UTC"
# End:
Commit	Line	Data
c84bdaf6 LC	1	eval '(exit $?0)' && eval 'exec perl -wS "$0" ${1+"$@"}'
	2	& eval 'exec perl -wS "$0" $argv:q'
	3	if 0;
5b55e293 AW	4	# Convert git log output to ChangeLog format.
5b55e293 AW	5
7ae4e75a	6	my $VERSION = '2012-07-29 06:11'; # UTC
5b55e293 AW	7	# The definition above must lie within the first 8 lines in order
	8	# for the Emacs time-stamp write hook (at end) to update it.
	9	# If you change this file with Emacs, please let the write hook
	10	# do its job. Otherwise, update this string manually.
	11
5e69ceb7	12	# Copyright (C) 2008-2014 Free Software Foundation, Inc.
5b55e293 AW	13
	14	# This program is free software: you can redistribute it and/or modify
	15	# it under the terms of the GNU General Public License as published by
	16	# the Free Software Foundation, either version 3 of the License, or
	17	# (at your option) any later version.
	18
	19	# This program is distributed in the hope that it will be useful,
	20	# but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	# GNU General Public License for more details.
	23
	24	# You should have received a copy of the GNU General Public License
	25	# along with this program. If not, see <http://www.gnu.org/licenses/>.
	26
	27	# Written by Jim Meyering
	28
	29	use strict;
	30	use warnings;
	31	use Getopt::Long;
	32	use POSIX qw(strftime);
	33
	34	(my $ME = $0) =~ s\|.*/\|\|;
	35
	36	# use File::Coda; # http://meyering.net/code/Coda/
	37	END {
	38	defined fileno STDOUT or return;
	39	close STDOUT and return;
	40	warn "$ME: failed to close standard output: $!\n";
	41	$? \|\|= 1;
	42	}
	43
	44	sub usage ($)
	45	{
	46	my ($exit_code) = @_;
	47	my $STREAM = ($exit_code == 0 ? STDOUT : STDERR);
	48	if ($exit_code != 0)
	49	{
f0007cad	50	print $STREAM "Try '$ME --help' for more information.\n";
5b55e293 AW	51	}
	52	else
	53	{
	54	print $STREAM <<EOF;
	55	Usage: $ME [OPTIONS] [ARGS]
	56
	57	Convert git log output to ChangeLog format. If present, any ARGS
	58	are passed to "git log". To avoid ARGS being parsed as options to
	59	$ME, they may be preceded by '--'.
	60
	61	OPTIONS:
	62
7f1ea859 LC	63	--amend=FILE FILE maps from an SHA1 to perl code (i.e., s/old/new/) that
	64	makes a change to SHA1's commit log text or metadata.
	65	--append-dot append a dot to the first line of each commit message if
	66	there is no other punctuation or blank at the end.
005de2e8 LC	67	--no-cluster never cluster commit messages under the same date/author
	68	header; the default is to cluster adjacent commit messages
	69	if their headers are the same and neither commit message
	70	contains multiple paragraphs.
7ae4e75a LC	71	--srcdir=DIR the root of the source tree, from which the .git/
7ae4e75a LC	72	directory can be derived.
5b55e293 AW	73	--since=DATE convert only the logs since DATE;
5b55e293 AW	74	the default is to convert all log entries.
c84bdaf6 LC	75	--format=FMT set format string for commit subject and body;
	76	see 'man git-log' for the list of format metacharacters;
	77	the default is '%s%n%b%n'
005de2e8 LC	78	--strip-tab remove one additional leading TAB from commit message lines.
	79	--strip-cherry-pick remove data inserted by "git cherry-pick";
	80	this includes the "cherry picked from commit ..." line,
	81	and the possible final "Conflicts:" paragraph.
5b55e293 AW	82	--help display this help and exit
	83	--version output version information and exit
	84
	85	EXAMPLE:
	86
	87	$ME --since=2008-01-01 > ChangeLog
	88	$ME -- -n 5 foo > last-5-commits-to-branch-foo
	89
f0007cad LC	90	SPECIAL SYNTAX:
	91
	92	The following types of strings are interpreted specially when they appear
	93	at the beginning of a log message line. They are not copied to the output.
	94
	95	Copyright-paperwork-exempt: Yes
	96	Append the "(tiny change)" notation to the usual "date name email"
	97	ChangeLog header to mark a change that does not require a copyright
	98	assignment.
	99	Co-authored-by: Joe User <user\@example.com>
	100	List the specified name and email address on a second
	101	ChangeLog header, denoting a co-author.
	102	Signed-off-by: Joe User <user\@example.com>
	103	These lines are simply elided.
	104
7f1ea859 LC	105	In a FILE specified via --amend, comment lines (starting with "#") are ignored.
	106	FILE must consist of <SHA,CODE+> pairs where SHA is a 40-byte SHA1 (alone on
	107	a line) referring to a commit in the current project, and CODE refers to one
	108	or more consecutive lines of Perl code. Pairs must be separated by one or
	109	more blank line.
	110
	111	Here is sample input for use with --amend=FILE, from coreutils:
	112
	113	3a169f4c5d9159283548178668d2fae6fced3030
	114	# fix typo in title:
	115	s/all tile types/all file types/
	116
	117	1379ed974f1fa39b12e2ffab18b3f7a607082202
	118	# Due to a bug in vc-dwim, I mis-attributed a patch by Paul to myself.
	119	# Change the author to be Paul. Note the escaped "@":
f0007cad	120	s,Jim .*>,Paul Eggert <eggert\\\@cs.ucla.edu>,
7f1ea859	121
5b55e293 AW	122	EOF
	123	}
	124	exit $exit_code;
	125	}
	126
	127	# If the string $S is a well-behaved file name, simply return it.
	128	# If it contains white space, quotes, etc., quote it, and return the new string.
	129	sub shell_quote($)
	130	{
	131	my ($s) = @_;
	132	if ($s =~ m![^\w+/.,-]!)
	133	{
	134	# Convert each single quote to '\''
	135	$s =~ s/\'/\'\\\'\'/g;
	136	# Then single quote the string.
	137	$s = "'$s'";
	138	}
	139	return $s;
	140	}
	141
	142	sub quoted_cmd(@)
	143	{
	144	return join (' ', map {shell_quote $_} @_);
	145	}
	146
7f1ea859 LC	147	# Parse file F.
	148	# Comment lines (starting with "#") are ignored.
	149	# F must consist of <SHA,CODE+> pairs where SHA is a 40-byte SHA1
	150	# (alone on a line) referring to a commit in the current project, and
	151	# CODE refers to one or more consecutive lines of Perl code.
	152	# Pairs must be separated by one or more blank line.
	153	sub parse_amend_file($)
5b55e293	154	{
7f1ea859 LC	155	my ($f) = @_;
	156
	157	open F, '<', $f
	158	or die "$ME: $f: failed to open for reading: $!\n";
	159
	160	my $fail;
	161	my $h = {};
	162	my $in_code = 0;
	163	my $sha;
	164	while (defined (my $line = <F>))
	165	{
	166	$line =~ /^\#/
	167	and next;
	168	chomp $line;
	169	$line eq ''
	170	and $in_code = 0, next;
	171
	172	if (!$in_code)
	173	{
	174	$line =~ /^([0-9a-fA-F]{40})$/
	175	or (warn "$ME: $f:$.: invalid line; expected an SHA1\n"),
	176	$fail = 1, next;
	177	$sha = lc $1;
	178	$in_code = 1;
	179	exists $h->{$sha}
	180	and (warn "$ME: $f:$.: duplicate SHA1\n"),
	181	$fail = 1, next;
	182	}
	183	else
	184	{
	185	$h->{$sha} \|\|= '';
	186	$h->{$sha} .= "$line\n";
	187	}
	188	}
	189	close F;
	190
	191	$fail
	192	and exit 1;
	193
	194	return $h;
	195	}
	196
7ae4e75a LC	197	# git_dir_option $SRCDIR
	198	#
	199	# From $SRCDIR, the --git-dir option to pass to git (none if $SRCDIR
	200	# is undef). Return as a list (0 or 1 element).
	201	sub git_dir_option($)
	202	{
	203	my ($srcdir) = @_;
	204	my @res = ();
	205	if (defined $srcdir)
	206	{
	207	my $qdir = shell_quote $srcdir;
	208	my $cmd = "cd $qdir && git rev-parse --show-toplevel";
	209	my $qcmd = shell_quote $cmd;
	210	my $git_dir = qx($cmd);
	211	defined $git_dir
	212	or die "$ME: cannot run $qcmd: $!\n";
	213	$? == 0
	214	or die "$ME: $qcmd had unexpected exit code or signal ($?)\n";
	215	chomp $git_dir;
	216	push @res, "--git-dir=$git_dir/.git";
	217	}
	218	@res;
	219	}
	220
7f1ea859 LC	221	{
7f1ea859 LC	222	my $since_date;
c84bdaf6	223	my $format_string = '%s%n%b%n';
7f1ea859 LC	224	my $amend_file;
7f1ea859 LC	225	my $append_dot = 0;
005de2e8 LC	226	my $cluster = 1;
	227	my $strip_tab = 0;
	228	my $strip_cherry_pick = 0;
7ae4e75a	229	my $srcdir;
5b55e293 AW	230	GetOptions
	231	(
	232	help => sub { usage 0 },
	233	version => sub { print "$ME version $VERSION\n"; exit },
	234	'since=s' => \$since_date,
c84bdaf6	235	'format=s' => \$format_string,
7f1ea859 LC	236	'amend=s' => \$amend_file,
7f1ea859 LC	237	'append-dot' => \$append_dot,
005de2e8 LC	238	'cluster!' => \$cluster,
	239	'strip-tab' => \$strip_tab,
	240	'strip-cherry-pick' => \$strip_cherry_pick,
7ae4e75a	241	'srcdir=s' => \$srcdir,
5b55e293 AW	242	) or usage 1;
5b55e293 AW	243
7f1ea859 LC	244	defined $since_date
	245	and unshift @ARGV, "--since=$since_date";
	246
	247	# This is a hash that maps an SHA1 to perl code (i.e., s/old/new/)
	248	# that makes a correction in the log or attribution of that commit.
	249	my $amend_code = defined $amend_file ? parse_amend_file $amend_file : {};
	250
7ae4e75a LC	251	my @cmd = ('git',
	252	git_dir_option $srcdir,
	253	qw(log --log-size),
7f1ea859	254	'--pretty=format:%H:%ct %an <%ae>%n%n'.$format_string, @ARGV);
5b55e293	255	open PIPE, '-\|', @cmd
f0007cad	256	or die ("$ME: failed to run '". quoted_cmd (@cmd) ."': $!\n"
5b55e293 AW	257	. "(Is your Git too old? Version 1.5.1 or later is required.)\n");
5b55e293 AW	258
f0007cad	259	my $prev_multi_paragraph;
5b55e293	260	my $prev_date_line = '';
7f1ea859	261	my @prev_coauthors = ();
5b55e293 AW	262	while (1)
	263	{
	264	defined (my $in = <PIPE>)
	265	or last;
	266	$in =~ /^log size (\d+)$/
	267	or die "$ME:$.: Invalid line (expected log size):\n$in";
	268	my $log_nbytes = $1;
	269
	270	my $log;
	271	my $n_read = read PIPE, $log, $log_nbytes;
	272	$n_read == $log_nbytes
	273	or die "$ME:$.: unexpected EOF\n";
	274
7f1ea859 LC	275	# Extract leading hash.
	276	my ($sha, $rest) = split ':', $log, 2;
	277	defined $sha
	278	or die "$ME:$.: malformed log entry\n";
	279	$sha =~ /^[0-9a-fA-F]{40}$/
	280	or die "$ME:$.: invalid SHA1: $sha\n";
	281
	282	# If this commit's log requires any transformation, do it now.
	283	my $code = $amend_code->{$sha};
	284	if (defined $code)
	285	{
	286	eval 'use Safe';
	287	my $s = new Safe;
	288	# Put the unpreprocessed entry into "$_".
	289	$_ = $rest;
	290
	291	# Let $code operate on it, safely.
	292	my $r = $s->reval("$code")
	293	or die "$ME:$.:$sha: failed to eval \"$code\":\n$@\n";
	294
	295	# Note that we've used this entry.
	296	delete $amend_code->{$sha};
	297
	298	# Update $rest upon success.
	299	$rest = $_;
	300	}
	301
005de2e8 LC	302	# Remove lines inserted by "git cherry-pick".
	303	if ($strip_cherry_pick)
	304	{
	305	$rest =~ s/^\sConflicts:\n.//sm;
	306	$rest =~ s/^\s*\(cherry picked from commit [\da-f]+\)\n//m;
	307	}
	308
7f1ea859	309	my @line = split "\n", $rest;
5b55e293 AW	310	my $author_line = shift @line;
	311	defined $author_line
	312	or die "$ME:$.: unexpected EOF\n";
	313	$author_line =~ /^(\d+) (.*>)$/
	314	or die "$ME:$.: Invalid line "
	315	. "(expected date/author/email):\n$author_line\n";
	316
f0007cad LC	317	# Format 'Copyright-paperwork-exempt: Yes' as a standard ChangeLog
	318	# `(tiny change)' annotation.
	319	my $tiny = (grep (/^Copyright-paperwork-exempt:\s+[Yy]es$/, @line)
	320	? ' (tiny change)' : '');
	321
	322	my $date_line = sprintf "%s %s$tiny\n",
	323	strftime ("%F", localtime ($1)), $2;
	324
	325	my @coauthors = grep /^Co-authored-by:.*$/, @line;
	326	# Omit meta-data lines we've already interpreted.
	327	@line = grep !/^(?:Signed-off-by:[ ].*>$
	328	\|Co-authored-by:[ ]
	329	\|Copyright-paperwork-exempt:[ ]
	330	)/x, @line;
	331
	332	# Remove leading and trailing blank lines.
	333	if (@line)
	334	{
	335	while ($line[0] =~ /^\s*$/) { shift @line; }
	336	while ($line[$#line] =~ /^\s*$/) { pop @line; }
	337	}
	338
	339	# Record whether there are two or more paragraphs.
	340	my $multi_paragraph = grep /^\s*$/, @line;
7f1ea859 LC	341
	342	# Format 'Co-authored-by: A U Thor <email@example.com>' lines in
	343	# standard multi-author ChangeLog format.
7f1ea859 LC	344	for (@coauthors)
	345	{
	346	s/^Co-authored-by:\s*/\t /;
	347	s/\s*</ </;
	348
	349	/<.?@.\..*>/
	350	or warn "$ME: warning: missing email address for "
	351	. substr ($_, 5) . "\n";
	352	}
	353
005de2e8 LC	354	# If clustering of commit messages has been disabled, if this header
	355	# would be different from the previous date/name/email/coauthors header,
	356	# or if this or the previous entry consists of two or more paragraphs,
	357	# then print the header.
	358	if ( ! $cluster
	359	\|\| $date_line ne $prev_date_line
	360	\|\| "@coauthors" ne "@prev_coauthors"
	361	\|\| $multi_paragraph
	362	\|\| $prev_multi_paragraph)
5b55e293 AW	363	{
	364	$prev_date_line eq ''
	365	or print "\n";
	366	print $date_line;
7f1ea859 LC	367	@coauthors
7f1ea859 LC	368	and print join ("\n", @coauthors), "\n";
5b55e293 AW	369	}
5b55e293 AW	370	$prev_date_line = $date_line;
7f1ea859	371	@prev_coauthors = @coauthors;
f0007cad	372	$prev_multi_paragraph = $multi_paragraph;
5b55e293 AW	373
	374	# If there were any lines
	375	if (@line == 0)
	376	{
	377	warn "$ME: warning: empty commit message:\n $date_line\n";
	378	}
	379	else
	380	{
7f1ea859 LC	381	if ($append_dot)
	382	{
	383	# If the first line of the message has enough room, then
	384	if (length $line[0] < 72)
	385	{
	386	# append a dot if there is no other punctuation or blank
	387	# at the end.
	388	$line[0] =~ /[[:punct:]\s]$/
	389	or $line[0] .= '.';
	390	}
	391	}
5b55e293	392
005de2e8 LC	393	# Remove one additional leading TAB from each line.
	394	$strip_tab
	395	and map { s/^\t// } @line;
	396
5b55e293 AW	397	# Prefix each non-empty line with a TAB.
	398	@line = map { length $_ ? "\t$_" : '' } @line;
	399
	400	print "\n", join ("\n", @line), "\n";
	401	}
	402
	403	defined ($in = <PIPE>)
	404	or last;
	405	$in ne "\n"
	406	and die "$ME:$.: unexpected line:\n$in";
	407	}
	408
	409	close PIPE
	410	or die "$ME: error closing pipe from " . quoted_cmd (@cmd) . "\n";
	411	# FIXME-someday: include $PROCESS_STATUS in the diagnostic
7f1ea859 LC	412
	413	# Complain about any unused entry in the --amend=F specified file.
	414	my $fail = 0;
	415	foreach my $sha (keys %$amend_code)
	416	{
	417	warn "$ME:$amend_file: unused entry: $sha\n";
	418	$fail = 1;
	419	}
	420
	421	exit $fail;
5b55e293 AW	422	}
	423
	424	# Local Variables:
c84bdaf6	425	# mode: perl
5b55e293 AW	426	# indent-tabs-mode: nil
	427	# eval: (add-hook 'write-file-hooks 'time-stamp)
	428	# time-stamp-start: "my $VERSION = '"
	429	# time-stamp-format: "%:y-%02m-%02d %02H:%02M"
	430	# time-stamp-time-zone: "UTC"
	431	# time-stamp-end: "'; # UTC"
	432	# End: