code.delx.au - gnu-emacs/blob - build-aux/git-hooks/commit-msg

   1 #!/bin/sh
   2 # Check the format of GNU Emacs change log entries.
   3
   4 # Copyright 2014-2015 Free Software Foundation, Inc.
   5
   6 # This file is part of GNU Emacs.
   7
   8 # GNU Emacs 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 of the License, or
  11 # (at your option) any later version.
  12
  13 # GNU Emacs 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 GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  20
  21 # Written by Paul Eggert.
  22
  23 # Prefer gawk if available, as it handles NUL bytes properly.
  24 if type gawk >/dev/null 2>&1; then
  25   awk=gawk
  26 else
  27   awk=awk
  28 fi
  29
  30 # Use a UTF-8 locale if available, so that the UTF-8 check works.
  31 # Use U+00A2 CENT SIGN to test whether the locale works.
  32 cent_sign_utf8_format='\302\242\n'
  33 cent_sign=`printf "$cent_sign_utf8_format"`
  34 print_at_sign='{print substr("'$cent_sign'@", 2)}'
  35 at_sign=`$awk "$print_at_sign" 2>/dev/null`
  36 if test "$at_sign" != @; then
  37   at_sign=`LC_ALL=en_US.UTF-8 $awk "$print_at_sign" 2>/dev/null`
  38   if test "$at_sign" = @; then
  39     LC_ALL=en_US.UTF-8; export LC_ALL
  40   fi
  41 fi
  42
  43 # Check the log entry.
  44 exec $awk -v at_sign="$at_sign" -v cent_sign="$cent_sign" '
  45   BEGIN {
  46     # These regular expressions assume traditional Unix unibyte behavior.
  47     # They are needed for old or broken versions of awk, e.g.,
  48     # mawk 1.3.3 (1996), Gawk 3.0.4 (1999).
  49     space = "[ \f\n\r\t\v]"
  50     non_space = "[^ \f\n\r\t\v]"
  51     non_print = "[\1-\37\177]"
  52
  53     # Prefer POSIX regular expressions if available, as they do a
  54     # better job of checking.  Similarly, prefer POSIX negated
  55     # expressions if UTF-8 also works.
  56     if (" " ~ /[[:space:]]/) {
  57       space = "[[:space:]]"
  58       if (at_sign == "@" && cent_sign ~ /^[[:print:]]$/) {
  59         non_space = "[^[:space:]]"
  60         non_print = "[^[:print:]]"
  61       }
  62     }
  63   }
  64
  65   /^#/ { next }
  66
  67   !/^.*$/ {
  68     print "Invalid character (not UTF-8) in commit message"
  69     status = 1
  70   }
  71
  72   nlines == 0 && $0 !~ non_space { next }
  73
  74   { nlines++ }
  75
  76   nlines == 1 {
  77     # Ignore special markers used by "git rebase --autosquash".
  78     if (! sub(/^fixup! /, ""))
  79       sub(/^squash! /, "")
  80
  81     if ($0 ~ "^" space) {
  82       print "White space at start of commit message'\''s first line"
  83       status = 1
  84     }
  85   }
  86
  87   nlines == 2 && $0 ~ non_space {
  88     print "Nonempty second line in commit message"
  89     status = 1
  90   }
  91
  92   {
  93     # Expand tabs to spaces for length calculations etc.
  94     while (match($0, /\t/)) {
  95       before_tab = substr($0, 1, RSTART - 1)
  96       after_tab = substr($0, RSTART + 1)
  97       $0 = sprintf("%s%*s%s", before_tab, 8 - (RSTART - 1) % 8, "", after_tab)
  98     }
  99   }
 100
 101   78 < length && $0 ~ space {
 102     print "Line longer than 78 characters in commit message"
 103     status = 1
 104   }
 105
 106   140 < length {
 107     print "Word longer than 140 characters in commit message"
 108     status = 1
 109   }
 110
 111   /^Signed-off-by: / {
 112     print "'\''Signed-off-by:'\'' in commit message"
 113     status = 1
 114   }
 115
 116   $0 ~ non_print {
 117     print "Unprintable character in commit message"
 118     status = 1
 119   }
 120
 121   END {
 122     if (nlines == 0) {
 123       print "Empty commit message"
 124       status = 1
 125     }
 126     if (status != 0) {
 127       print "Commit aborted; please see the file 'CONTRIBUTE'"
 128     }
 129     exit status
 130   }
 131 ' <"$1"