build-aux/update-copyright

   1 #!/bin/sh
   2 #! -*-perl-*-
   3
   4 # Update an FSF copyright year list to include the current year.
   5
   6 # Copyright (C) 2009-2020 Free Software Foundation, Inc.
   7 #
   8 # This program is free software: you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation; either version 3, or (at your option)
  11 # any later version.
  12 #
  13 # This program is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  20 #
  21 # Written by Jim Meyering and Joel E. Denny
  22
  23 # This script updates an FSF copyright year list to include the current year.
  24 # Usage: update-copyright [FILE...]
  25 #
  26 # The arguments to this script should be names of files that contain
  27 # copyright statements to be updated.  The copyright holder's name
  28 # defaults to "Free Software Foundation, Inc." but may be changed to
  29 # any other name by using the "UPDATE_COPYRIGHT_HOLDER" environment
  30 # variable.
  31 #
  32 # For example, you might wish to use the update-copyright target rule
  33 # in maint.mk from gnulib's maintainer-makefile module.
  34 #
  35 # Iff a copyright statement is recognized in a file and the final
  36 # year is not the current year, then the statement is updated for the
  37 # new year and it is reformatted to:
  38 #
  39 #   1. Fit within 72 columns.
  40 #   2. Convert 2-digit years to 4-digit years by prepending "19".
  41 #   3. Expand copyright year intervals.  (See "Environment variables"
  42 #      below.)
  43 #
  44 # A warning is printed for every file for which no copyright
  45 # statement is recognized.
  46 #
  47 # Each file's copyright statement must be formatted correctly in
  48 # order to be recognized.  For example, each of these is fine:
  49 #
  50 #   Copyright @copyright{} 1990-2005, 2007-2009 Free Software
  51 #   Foundation, Inc.
  52 #
  53 #   # Copyright (C) 1990-2005, 2007-2009 Free Software
  54 #   # Foundation, Inc.
  55 #
  56 #   /*
  57 #    * Copyright &copy; 90,2005,2007-2009
  58 #    * Free Software Foundation, Inc.
  59 #    */
  60 #
  61 # However, the following format is not recognized because the line
  62 # prefix changes after the first line:
  63 #
  64 #   ## Copyright (C) 1990-2005, 2007-2009 Free Software
  65 #   #  Foundation, Inc.
  66 #
  67 # However, any correctly formatted copyright statement following
  68 # a non-matching copyright statements would be recognized.
  69 #
  70 # The exact conditions that a file's copyright statement must meet
  71 # to be recognized are:
  72 #
  73 #   1. It is the first copyright statement that meets all of the
  74 #      following conditions.  Subsequent copyright statements are
  75 #      ignored.
  76 #   2. Its format is "Copyright (C)", then a list of copyright years,
  77 #      and then the name of the copyright holder.
  78 #   3. The "(C)" takes one of the following forms or is omitted
  79 #      entirely:
  80 #
  81 #        A. (C)
  82 #        B. (c)
  83 #        C. @copyright{}
  84 #        D. &copy;
  85 #        E. ©
  86 #
  87 #   4. The "Copyright" appears at the beginning of a line, except that it
  88 #      may be prefixed by any sequence (e.g., a comment) of no more than
  89 #      5 characters -- including white space.
  90 #   5. Iff such a prefix is present, the same prefix appears at the
  91 #      beginning of each remaining line within the FSF copyright
  92 #      statement.  There is one exception in order to support C-style
  93 #      comments: if the first line's prefix contains nothing but
  94 #      whitespace surrounding a "/*", then the prefix for all subsequent
  95 #      lines is the same as the first line's prefix except with each of
  96 #      "/" and possibly "*" replaced by a " ".  The replacement of "*"
  97 #      by " " is consistent throughout all subsequent lines.
  98 #   6. Blank lines, even if preceded by the prefix, do not appear
  99 #      within the FSF copyright statement.
 100 #   7. Each copyright year is 2 or 4 digits, and years are separated by
 101 #      commas, "-", or "--".  Whitespace may appear after commas.
 102 #
 103 # Environment variables:
 104 #
 105 #   1. If UPDATE_COPYRIGHT_FORCE=1, a recognized FSF copyright statement
 106 #      is reformatted even if it does not need updating for the new
 107 #      year.  If unset or set to 0, only updated FSF copyright
 108 #      statements are reformatted.
 109 #   2. If UPDATE_COPYRIGHT_USE_INTERVALS=1, every series of consecutive
 110 #      copyright years (such as 90, 1991, 1992-2007, 2008) in a
 111 #      reformatted FSF copyright statement is collapsed to a single
 112 #      interval (such as 1990-2008).  If unset or set to 0, all existing
 113 #      copyright year intervals in a reformatted FSF copyright statement
 114 #      are expanded instead.
 115 #      If UPDATE_COPYRIGHT_USE_INTERVALS=2, convert a sequence with gaps
 116 #      to the minimal containing range.  For example, convert
 117 #      2000, 2004-2007, 2009 to 2000-2009.
 118 #   3. For testing purposes, you can set the assumed current year in
 119 #      UPDATE_COPYRIGHT_YEAR.
 120 #   4. The default maximum line length for a copyright line is 72.
 121 #      Set UPDATE_COPYRIGHT_MAX_LINE_LENGTH to use a different length.
 122 #   5. Set UPDATE_COPYRIGHT_HOLDER if the copyright holder is other
 123 #      than "Free Software Foundation, Inc.".
 124
 125 # This is a prologue that allows to run a perl script as an executable
 126 # on systems that are compliant to a POSIX version before POSIX:2017.
 127 # On such systems, the usual invocation of an executable through execlp()
 128 # or execvp() fails with ENOEXEC if it is a script that does not start
 129 # with a #! line.  The script interpreter mentioned in the #! line has
 130 # to be /bin/sh, because on GuixSD systems that is the only program that
 131 # has a fixed file name.  The second line is essential for perl and is
 132 # also useful for editing this file in Emacs.  The next two lines below
 133 # are valid code in both sh and perl.  When executed by sh, they re-execute
 134 # the script through the perl program found in $PATH.  The '-x' option
 135 # is essential as well; without it, perl would re-execute the script
 136 # through /bin/sh.  When executed by perl, the next two lines are a no-op.
 137 eval 'exec perl -wSx -0777 -pi "$0" "$@"'
 138      if 0;
 139
 140 my $VERSION = '2020-04-04.15:07'; # UTC
 141 # The definition above must lie within the first 8 lines in order
 142 # for the Emacs time-stamp write hook (at end) to update it.
 143 # If you change this file with Emacs, please let the write hook
 144 # do its job.  Otherwise, update this string manually.
 145
 146 use strict;
 147 use warnings;
 148
 149 my $copyright_re = 'Copyright';
 150 my $circle_c_re = '(?:\([cC]\)|@copyright\{}|\\\\\(co|&copy;|©)';
 151 my $holder = $ENV{UPDATE_COPYRIGHT_HOLDER};
 152 $holder ||= 'Free Software Foundation, Inc.';
 153 my $prefix_max = 5;
 154 my $margin = $ENV{UPDATE_COPYRIGHT_MAX_LINE_LENGTH};
 155 !$margin || $margin !~ m/^\d+$/
 156   and $margin = 72;
 157
 158 my $tab_width = 8;
 159
 160 my $this_year = $ENV{UPDATE_COPYRIGHT_YEAR};
 161 if (!$this_year || $this_year !~ m/^\d{4}$/)
 162   {
 163     my ($sec, $min, $hour, $mday, $month, $year) = localtime (time ());
 164     $this_year = $year + 1900;
 165   }
 166
 167 # Unless the file consistently uses "\r\n" as the EOL, use "\n" instead.
 168 my $eol = /(?:^|[^\r])\n/ ? "\n" : "\r\n";
 169
 170 my $leading;
 171 my $prefix;
 172 my $ws_re;
 173 my $stmt_re;
 174 while (/(^|\n)(.{0,$prefix_max})$copyright_re/g)
 175   {
 176     $leading = "$1$2";
 177     $prefix = $2;
 178     if ($prefix =~ /^(\s*\/)\*(\s*)$/)
 179       {
 180         $prefix =~ s,/, ,;
 181         my $prefix_ws = $prefix;
 182         $prefix_ws =~ s/\*/ /; # Only whitespace.
 183         if (/\G(?:[^*\n]|\*[^\/\n])*\*?\n$prefix_ws/)
 184           {
 185             $prefix = $prefix_ws;
 186           }
 187       }
 188     $ws_re = '[ \t\r\f]'; # \s without \n
 189     $ws_re =
 190       "(?:$ws_re*(?:$ws_re|\\n" . quotemeta($prefix) . ")$ws_re*)";
 191     my $holder_re = $holder;
 192     $holder_re =~ s/\s/$ws_re/g;
 193     my $stmt_remainder_re =
 194       "(?:$ws_re$circle_c_re)?"
 195       . "$ws_re(?:(?:\\d\\d)?\\d\\d(?:,$ws_re?|--?))*"
 196       . "((?:\\d\\d)?\\d\\d)$ws_re$holder_re";
 197     if (/\G$stmt_remainder_re/)
 198       {
 199         $stmt_re =
 200           quotemeta($leading) . "($copyright_re$stmt_remainder_re)";
 201         last;
 202       }
 203   }
 204 if (defined $stmt_re)
 205   {
 206     /$stmt_re/ or die; # Should never die.
 207     my $stmt = $1;
 208     my $final_year_orig = $2;
 209
 210     # Handle two-digit year numbers like "98" and "99".
 211     my $final_year = $final_year_orig;
 212     $final_year <= 99
 213       and $final_year += 1900;
 214
 215     if ($final_year != $this_year)
 216       {
 217         # Update the year.
 218         $stmt =~ s/\b$final_year_orig\b/$final_year, $this_year/;
 219       }
 220     if ($final_year != $this_year || $ENV{'UPDATE_COPYRIGHT_FORCE'})
 221       {
 222         # Normalize all whitespace including newline-prefix sequences.
 223         $stmt =~ s/$ws_re/ /g;
 224
 225         # Put spaces after commas.
 226         $stmt =~ s/, ?/, /g;
 227
 228         # Convert 2-digit to 4-digit years.
 229         $stmt =~ s/(\b\d\d\b)/19$1/g;
 230
 231         # Make the use of intervals consistent.
 232         if (!$ENV{UPDATE_COPYRIGHT_USE_INTERVALS})
 233           {
 234             $stmt =~ s/(\d{4})--?(\d{4})/join(', ', $1..$2)/eg;
 235           }
 236         else
 237           {
 238             my $ndash = $ARGV =~ /\.tex(i(nfo)?)?$/ ? "--" : "-";
 239
 240             $stmt =~
 241               s/
 242                 (\d{4})
 243                 (?:
 244                   (,\ |--?)
 245                   ((??{
 246                     if   ($2 ne ', ') { '\d{4}'; }
 247                     elsif (!$3)       { $1 + 1;  }
 248                     else              { $3 + 1;  }
 249                   }))
 250                 )+
 251               /$1$ndash$3/gx;
 252
 253             # When it's 2, emit a single range encompassing all year numbers.
 254             $ENV{UPDATE_COPYRIGHT_USE_INTERVALS} == 2
 255               and $stmt =~ s/\b(\d{4})\b.*\b(\d{4})\b/$1$ndash$2/;
 256           }
 257
 258         # Format within margin.
 259         my $stmt_wrapped;
 260         my $text_margin = $margin - length($prefix);
 261         if ($prefix =~ /^(\t+)/)
 262           {
 263             $text_margin -= length($1) * ($tab_width - 1);
 264           }
 265         while (length $stmt)
 266           {
 267             if (($stmt =~ s/^(.{1,$text_margin})(?: |$)//)
 268                 || ($stmt =~ s/^([\S]+)(?: |$)//))
 269               {
 270                 my $line = $1;
 271                 $stmt_wrapped .= $stmt_wrapped ? "$eol$prefix" : $leading;
 272                 $stmt_wrapped .= $line;
 273               }
 274             else
 275               {
 276                 # Should be unreachable, but we don't want an infinite
 277                 # loop if it can be reached.
 278                 die;
 279               }
 280           }
 281
 282         # Replace the old copyright statement.
 283         s/$stmt_re/$stmt_wrapped/;
 284       }
 285   }
 286 else
 287   {
 288     print STDERR "$ARGV: warning: copyright statement not found\n";
 289   }
 290
 291 # Hey Emacs!
 292 # Local variables:
 293 # coding: utf-8
 294 # mode: perl
 295 # indent-tabs-mode: nil
 296 # eval: (add-hook 'before-save-hook 'time-stamp)
 297 # time-stamp-line-limit: 200
 298 # time-stamp-start: "my $VERSION = '"
 299 # time-stamp-format: "%:y-%02m-%02d.%02H:%02M"
 300 # time-stamp-time-zone: "UTC0"
 301 # time-stamp-end: "'; # UTC"
 302 # End: