ksplice.pl.in

   1 #!/usr/bin/perl
   2
   3 # Copyright (C) 2008  Anders Kaseorg <andersk@mit.edu>,
   4 #                     Jeffrey Brian Arnold <jbarnold@mit.edu>,
   5 #                     Tim Abbott <tabbott@mit.edu>
   6 #
   7 # This program is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License, version 2.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program; if not, write to the Free Software
  17 # Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
  18 # 02110-1301, USA.
  19
  20 use strict;
  21 use warnings;
  22 use lib 'KSPLICE_DATA_DIR';
  23 use ksplice;
  24 use File::Copy;
  25 use Digest::MD5;
  26
  27 sub empty_diff {
  28         my ($out) = @_;
  29         my ($obj) = $out =~ /^(.*)\.KSPLICE$/ or die;
  30         unlink "$obj.KSPLICE_primary" if (-e "$obj.KSPLICE_primary");
  31         unlink "$obj.KSPLICE_helper" if (-e "$obj.KSPLICE_helper");
  32         open OUT, '>', "$out.tmp";
  33         close OUT;
  34         rename "$out.tmp", $out;
  35 }
  36
  37 sub do_snap {
  38         my ($out) = @_;
  39         my ($obj) = $out =~ /^(.*)\.KSPLICE$/ or die;
  40         die if (!-e $obj);
  41         unlink "$obj.KSPLICE_pre" if (-e "$obj.KSPLICE_pre");
  42         empty_diff($out);
  43 }
  44
  45 sub do_diff {
  46         my ($out) = @_;
  47         my ($obj) = $out =~ /^(.*)\.KSPLICE$/ or die;
  48         my $obj_old = "$obj.KSPLICE_pre";
  49         return do_snap($out) if (!-e $obj_old);
  50         die if (!-e $obj);
  51         if (system('cmp', '-s', '--', $obj_old, $obj) == 0) {
  52                 unlink $obj_old;
  53                 return empty_diff($out);
  54         }
  55
  56         my ($bits, $sections, $entrysyms) = split("\n", runsuc("objdiff", $obj_old, $obj));
  57         die if ($bits ne '32' && $bits ne '64');
  58         return empty_diff($out) if ($sections eq '' && $entrysyms eq '');
  59
  60         copy($obj, "$obj.KSPLICE_primary");
  61         copy($obj_old, "$obj.KSPLICE_helper");
  62
  63         open OBJ, '<', $obj or die;
  64         open OBJ_OLD, '<', $obj_old or die;
  65         my $tag = Digest::MD5->new->addfile(*OBJ)->addfile(*OBJ_OLD)->hexdigest;
  66         close OBJ;
  67         close OBJ_OLD;
  68
  69         runsuc("objmanip", "$obj.KSPLICE_primary", "keep-primary", "____${tag}", "_post", split(/\s/, $sections));
  70         runsuc("objmanip", "$obj.KSPLICE_helper", "keep-helper", "____${tag}", "_pre");
  71
  72         runsuc("objmanip", "$obj.KSPLICE_primary", "sizelist", "____${tag}", "_post");
  73         runsuc("objmanip", "$obj.KSPLICE_helper", "sizelist", "____${tag}", "_pre");
  74
  75         runsuc("objmanip", "$obj.KSPLICE_primary", "patchlist", "____${tag}", "_pre", "_post", split(/\s/, $entrysyms));
  76
  77         open OUT, '>', "$out.tmp";
  78         print OUT "$bits\n";
  79         close OUT;
  80         rename "$out.tmp", $out;
  81 }
  82
  83 sub do_combine {
  84         my ($out, @ins) = @_;
  85         my @objs;
  86         my $outbits = undef;
  87         foreach my $in (@ins) {
  88                 next if (!-s $in);
  89                 my ($obj) = $in =~ /^(.*)\.KSPLICE$/ or die;
  90                 push @objs, $obj;
  91
  92                 open IN, '<', $in;
  93
  94                 chomp(my $bits = <IN>);
  95                 die if (defined $outbits && $outbits ne $bits);
  96                 $outbits = $bits;
  97
  98                 close IN;
  99         }
 100
 101         return empty_diff($out) unless (defined $outbits);
 102
 103         my ($obj) = $out =~ /^(.*)\.KSPLICE$/ or die;
 104         if (@objs == 1) {
 105                 copy "$objs[0].KSPLICE_primary", "$obj.KSPLICE_primary";
 106                 copy "$objs[0].KSPLICE_helper", "$obj.KSPLICE_helper";
 107         } else {
 108                 system("ld", "-r", "-o",
 109                        map { "$_.KSPLICE_primary" } ($obj, @objs));
 110                 system("ld", "-r", "-o",
 111                        map { "$_.KSPLICE_helper" } ($obj, @objs));
 112         }
 113
 114         open OUT, '>', "$out.tmp";
 115         print OUT "$outbits\n";
 116         close OUT;
 117         rename "$out.tmp", $out;
 118 }
 119
 120 sub do_rmsyms {
 121         my ($obj, @rmsyms) = @_;
 122         my $relocs = runsuc("objmanip", $obj, "rmsyms", @rmsyms);
 123 }
 124
 125 sub do_system_map_lookup {
 126         my ($symarg) = @_;
 127         open(SYMS, "<", "$ENV{KSPLICE_CONFIG_DIR}/System.map") or die;
 128         my $line;
 129         while(defined($line = <SYMS>)) {
 130                 my ($addr, $type, $sym, $mod) = split(/\s+/, $line);
 131                 if ($sym eq $symarg) { print $addr; last; }
 132         }
 133         close(SYMS);
 134 }
 135
 136 my %handlers = (
 137         'snap' => \&do_snap,
 138         'diff' => \&do_diff,
 139         'combine' => \&do_combine,
 140         'rmsyms' => \&do_rmsyms,
 141         'system_map_lookup' => \&do_system_map_lookup,
 142 );
 143
 144 my ($cmd, @args) = @ARGV;
 145 if (exists $handlers{$cmd}) {
 146         my $handler = $handlers{$cmd};
 147         &$handler(@args);
 148 } else {
 149         print "Usage: ksplice.pl ", join('|', keys %handlers), " ...\n";
 150 };