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#!/usr/bin/perl -w
use strict;
=for comment
Documentation for this is in bisect-runner.pl
=cut
# The default, auto_abbrev will treat -e as an abbreviation of --end
# Which isn't what we want.
use Getopt::Long qw(:config pass_through no_auto_abbrev);
use File::Path qw(mkpath);
my ($start, $end, $validate, $usage, $bad, $jobs, $make, $gold,
$module, $with_module);
my $need_cpan_config;
my $cpan_config_dir;
$bad = !GetOptions('start=s' => \$start, 'end=s' => \$end,
'jobs|j=i' => \$jobs, 'make=s' => \$make, 'gold=s' => \$gold,
validate => \$validate, 'usage|help|?' => \$usage,
'module=s' => \$module, 'with-module=s' => \$with_module,
'cpan-config-dir=s' => \$cpan_config_dir);
unshift @ARGV, '--help' if $bad || $usage;
unshift @ARGV, '--validate' if $validate;
if ($module || $with_module) {
unshift @ARGV, '--module', $module if defined $module;
unshift @ARGV, '--with-module', $with_module if defined $with_module;
if ($cpan_config_dir) {
my $c = File::Spec->catfile($cpan_config_dir, 'CPAN', 'MyConfig.pm');
die "--cpan-config-dir: $c does not exist\n" unless -e $c;
unshift @ARGV, '--cpan-config-dir', $cpan_config_dir;
} else {
$need_cpan_config = 1;
}
}
my $runner = $0;
$runner =~ s/bisect\.pl/bisect-runner.pl/;
die "Can't find bisect runner $runner" unless -f $runner;
system $^X, $runner, '--check-args', '--check-shebang', @ARGV and exit 255;
exit 255 if $bad;
exit 0 if $usage;
my $start_time = time;
if (!defined $jobs &&
!($^O eq 'hpux' && system((defined $make ? $make : 'make')
. ' --version >/dev/null 2>&1'))) {
# Try to default to (ab)use all the CPUs:
my $cpus;
if (open my $fh, '<', '/proc/cpuinfo') {
while (<$fh>) {
++$cpus if /^processor\s+:\s+\d+$/;
}
} elsif (-x '/sbin/sysctl' || -x '/usr/sbin/sysctl') {
my $sysctl = '/sbin/sysctl';
$sysctl = "/usr$sysctl" unless -x $sysctl;
$cpus = $1 if `$sysctl hw.ncpu` =~ /^hw\.ncpu: (\d+)$/;
} elsif (-x '/usr/bin/getconf') {
$cpus = $1 if `/usr/bin/getconf _NPROCESSORS_ONLN` =~ /^(\d+)$/;
}
$jobs = defined $cpus ? $cpus + 1 : 2;
}
unshift @ARGV, '--jobs', $jobs if defined $jobs;
unshift @ARGV, '--make', $make if defined $make;
if ($need_cpan_config) {
# Make sure we have a CPAN::MyConfig so if we start at an old
# revision CPAN doesn't ask for user input to configure itself
my $cdir = File::Spec->catdir($ENV{HOME},".cpan","CPAN");
my $cfile = File::Spec->catfile($cdir, "MyConfig.pm");
unless (-e $cfile) {
printf <<EOF;
I could not find a CPAN::MyConfig. We need to create one now so that
you can bisect with --module or --with-module. I'll boot up the CPAN
shell for you. Feel free to use defaults or change things as needed.
We recommend using 'manual' over 'local::lib' if it asks.
Type 'quit' when finished.
EOF
system("$^X -MCPAN -e shell");
}
}
# We try these in this order for the start revision if none is specified.
my @stable = map {chomp $_; $_} grep {/v5\.[0-9]+[02468]\.0$/} `git tag -l`;
die "git tag -l didn't seem to return any tags for stable releases"
unless @stable;
unshift @stable, qw(perl-5.005 perl-5.6.0 perl-5.8.0);
{
my ($dev_C, $ino_C) = stat 'Configure';
my ($dev_c, $ino_c) = stat 'configure';
if (defined $dev_C && defined $dev_c
&& $dev_C == $dev_c && $ino_C == $ino_c) {
print "You seem to be on a case-insensitive file system.\n\n";
} else {
unshift @stable, qw(perl-5.002 perl-5.003 perl-5.004)
}
}
unshift @ARGV, '--gold', defined $gold ? $gold : $stable[-1];
if (!defined $end) {
# If we have a branch blead, use that as the end
$end = `git rev-parse --verify --quiet blead`;
die unless defined $end;
if (!length $end) {
# Else use whichever is newer - HEAD, or the most recent stable tag.
if (`git rev-list -n1 HEAD ^$stable[-1]` eq "") {
$end = pop @stable;
} else {
$end = 'HEAD';
}
}
}
# Canonicalising branches to revisions before moving the checkout permits one
# to use revisions such as 'HEAD' for --start or --end
foreach ($start, $end) {
next unless $_;
$_ = `git rev-parse $_`;
die unless defined $_;
chomp;
}
{
my $modified = my @modified = `git ls-files --modified --deleted --others`;
my ($dev0, $ino0) = stat $0;
die "Can't stat $0: $!" unless defined $ino0;
my ($dev1, $ino1) = stat 'Porting/bisect.pl';
my $inplace = defined $dev1 && $dev0 == $dev1 && $ino0 == $ino1;
if ($modified) {
my $final = $inplace
? "Can't run a bisect using a dirty directory containing $runner"
: "You can use 'git clean -Xdf' to cleanup the ignored files";
die "This checkout is not clean, found file(s):\n",
join("\t","",@modified),
"$modified modified, untracked, or other file(s)\n",
"These files may not show in git status as they may be ignored.\n",
"$final.\n";
}
if ($inplace) {
# We assume that it's safe to copy the runner to the temporary
# directory and run it from there, because a shared /tmp should be +t
# and hence others are not be able to delete or rename our file.
require File::Temp;
my ($to, $toname) = File::Temp::tempfile();
die "Can't create tempfile"
unless $to;
open my $from, '<', $runner
or die "Can't open '$runner': $!";
local $/;
print {$to} <$from>
or die "Can't copy from '$runner' to '$toname': $!";
close $from
or die "Can't close '$runner': $!";
close $to
or die "Can't close '$toname': $!";
chmod 0500, $toname
or die "Can't chmod 0500, '$toname': $!";
$runner = $toname;
system $^X, $runner, '--check-args', @ARGV
and die "Can't run inplace for some reason. :-(";
}
}
sub validate {
my $commit = shift;
if (defined $start && `git rev-list -n1 $commit ^$start^` eq "") {
print "Skipping $commit, as it is earlier than $start\n";
return;
}
if (defined $end && `git rev-list -n1 $end ^$commit^` eq "") {
print "Skipping $commit, as it is more recent than $end\n";
return;
}
print "Testing $commit...\n";
system "git checkout $commit </dev/null" and die;
my $ret = system $^X, $runner, '--no-clean', @ARGV;
die "Runner returned $ret, not 0 for revision $commit" if $ret;
system 'git clean -dxf </dev/null' and die;
system 'git reset --hard HEAD </dev/null' and die;
return $commit;
}
if ($validate) {
require Text::Wrap;
my @built = map {validate $_} 'blead', reverse @stable;
if (@built) {
print Text::Wrap::wrap("", "", "Successfully validated @built\n");
exit 0;
}
print "Did not validate anything\n";
exit 1;
}
my $git_version = `git --version`;
if (defined $git_version
&& $git_version =~ /\Agit version (\d+\.\d+\.\d+)(.*)/) {
$git_version = eval "v$1";
} else {
$git_version = v0.0.0;
}
if ($git_version ge v1.6.6) {
system "git bisect reset HEAD" and die;
} else {
system "git bisect reset" and die;
}
# Sanity check the first and last revisions:
system "git checkout $end" and die;
my $ret = system $^X, $runner, @ARGV;
die "Runner returned $ret for end revision" unless $ret;
die "Runner returned $ret for end revision, which is a skip"
if $ret == 125 * 256;
if (defined $start) {
system "git checkout $start" and die;
my $ret = system $^X, $runner, @ARGV;
die "Runner returned $ret, not 0 for start revision" if $ret;
} else {
# Try to find the earliest version for which the test works
my @tried;
foreach my $try (@stable) {
if (`git rev-list -n1 $end ^$try^` eq "") {
print "Skipping $try, as it is more recent than end commit "
. (substr $end, 0, 16) . "\n";
# As @stable is supposed to be in age order, arguably we should
# last; here.
next;
}
system "git checkout $try" and die;
my $ret = system $^X, $runner, @ARGV;
if (!$ret) {
$start = $try;
last;
}
push @tried, $try;
}
die "Can't find a suitable start revision to default to.\nTried @tried"
unless defined $start;
}
system "git bisect start" and die;
system "git bisect good $start" and die;
system "git bisect bad $end" and die;
# And now get git bisect to do the hard work:
system 'git', 'bisect', 'run', $^X, $runner, @ARGV and die;
END {
my $end_time = time;
printf "That took %d seconds.\n", $end_time - $start_time
if defined $start_time;
}
=for comment
Documentation for this is in bisect-runner.pl
=cut
# ex: set ts=8 sts=4 sw=4 et: