1 #! /usr/bin/perl

     2 use strict;

     3 use warnings;

     4 use File::Temp;

     5 

     6 my $pattern = "# sha1:";

     7 

     8 die "need exactly one filename" if not @ARGV == 1;

     9 

    10 if ($0 =~ /chk/) {

    11     local $" = "";

    12     exit 0 if not -e $ARGV[0];

    13     my @file = <>;

    14 

    15     my $expected = "";

    16     $expected = pop @file if $file[-1] =~ /^$pattern/;

    17 

    18     my $tmp = new File::Temp;

    19     open(SHA1, "|sha1sum >" . $tmp->filename);

    20     print SHA1 @file;

    21     close(SHA1);

    22     seek($tmp, 0, 0);

    23 

    24     my $current = $pattern . <$tmp>;

    25 

    26     exit 0 if $current eq $expected;

    27     exit 1;

    28 }

    29 

    30 if ($0 =~ /sig/) {

    31     local $" = "";

    32     open(FILE, "+<$ARGV[0]") or die "Can't open $ARGV[0]: $!\n";

    33     my @file = <FILE>;

    34     pop @file if $file[-1] =~ /^$pattern/;

    35     seek(FILE, 0, 0);

    36     print FILE @file, $pattern;

    37     truncate(FILE, tell FILE);

    38     close FILE;

    39     open(SHA1, "|sha1sum >>$ARGV[0]");

    40     print SHA1 @file;

    41     close(SHA1);

    42 }