implemented checkout subcommand

diff --git a/pristine-tar b/pristine-tar
index a18649d..dcd1a9b 100755 (executable)
--- a/pristine-tar
+++ b/pristine-tar
@@ -10,9 +10,9 @@ B<pristine-tar> [-vdk] gentar delta tarball
 
 B<pristine-tar> [-vdk] gendelta tarball delta
 
-B<pristine-tar> commit tarball [upstream]
+B<pristine-tar> [-vdk] commit tarball [upstream]
 
-B<pristine-tar> checkout tarball
+B<pristine-tar> [-vdk] checkout tarball
 
 =head1 DESCRIPTION
 
@@ -115,7 +115,7 @@ use File::Temp;
 use File::Path;
 use File::Basename;
 use Getopt::Long;
-use Cwd;
+use Cwd qw{getcwd abs_path};
 
 # magic identification
 use constant GZIP_ID1            => 0x1F;
@@ -135,8 +135,8 @@ $ENV{LANG}='C';
 sub usage {
        print STDERR "Usage: pristine-tar [-vdk] gentar delta tarball\n";
        print STDERR "       pristine-tar [-vdk] gendelta tarball delta\n";
-       print STDERR "       pristine-tar commit tarball [upstream]\n";
-       print STDERR "       pristine-tar checkout tarball\n";
+       print STDERR "       pristine-tar [-vdk] commit tarball [upstream]\n";
+       print STDERR "       pristine-tar [-vdk] checkout tarball\n";
        exit 1;
 }
 
@@ -237,9 +237,9 @@ sub recreatetarball {
                        debug("$file is listed in the manifest but may not be present in the source directory");
                        $full_sweep=1;
 
-                       if ($options{create_missing}) {
-                               mkpath "$tempdir/workdir/$file";
-                       }
+                       # Avoid tar failing on the nonexistent item by
+                       # creating a dummy directory.
+                       mkpath "$tempdir/workdir/$file";
                }
                
                if (-d "$tempdir/workdir/$file" && (-u _ || -g _ || -k _)) {
@@ -283,6 +283,7 @@ sub recreatetarball {
 sub gentar {
        my $delta=shift;
        my $tarball=shift;
+       my %opts=@_;
 
        my $tempdir=tempdir();
        
@@ -315,7 +316,7 @@ sub gentar {
                close IN;
        }
 
-       recreatetarball($tempdir, ".", clobber_source => 1);
+       recreatetarball($tempdir, getcwd, clobber_source => 0, %opts);
        my $out=(-e "$tempdir/wrapper") ? $tarball.".tmp" : $tarball;
        doit("xdelta", "patch", "$tempdir/delta", "$tempdir/recreatetarball", $out);
 
@@ -426,16 +427,21 @@ sub export {
        
        my $vcs=vcstype();
        if ($vcs eq "git") {
-               # Convert $upstream into an object id.
-               my @reflines=map { chomp; $_ } `git show-ref \Q$upstream\E`;
-               if (! @reflines) {
-                       error "failed to find ref using: git show-ref $upstream"
+               if ($upstream =~ /[A-Za-z0-9]{40}/) {
+                       $id=$upstream;
                }
-               if (@reflines > 1) {
-                       error "more than one ref matches \"$upstream\":\n".
-                               join("\n", @reflines);
+               else {
+                       # Convert $upstream into an object id.
+                       my @reflines=map { chomp; $_ } `git show-ref \Q$upstream\E`;
+                       if (! @reflines) {
+                               error "failed to find ref using: git show-ref $upstream"
+                       }
+                       if (@reflines > 1) {
+                               error "more than one ref matches \"$upstream\":\n".
+                                       join("\n", @reflines);
+                       }
+                       ($id)=$reflines[0]=~/^([A-Za-z0-9]+)\s/;
                }
-               ($id)=$reflines[0]=~/^([A-Za-z0-9]+)\s/;
 
                doit("git archive --format=tar \Q$id\E | (cd '$dest' && tar x)");
        }
@@ -446,10 +452,44 @@ sub export {
        return ($dest, $id);
 }
 
-sub savedelta {
-       my $delta=shift;
+sub checkoutdelta {
        my $tarball=shift;
+
+       my $branch="pristine-tar";
+       my $deltafile=basename($tarball).".delta";
+       my $idfile=basename($tarball).".id";
+
+       my ($delta, $id);
+
+       my $vcs=vcstype();
+       if ($vcs eq "git") {
+               $delta=`git show $branch:\Q$deltafile\E`;
+               if ($?) {
+                       error "git show $branch:$deltafile failed";
+               }
+               if (! length $delta) {
+                       error "git show $branch:$deltafile returned no content";
+               }
+               $id=`git show $branch:\Q$idfile\E`;
+               if ($?) {
+                       error "git show $branch:$idfile failed";
+               }
+               chomp $id; # just in case..
+               if (! length $id) {
+                       error "git show $branch:$idfile returned no id";
+               }
+       }
+       else {
+               die "unsupported vcs $vcs";
+       }
+
+       return ($delta, $id);
+}
+
+sub commitdelta {
+       my $delta=shift;
        my $id=shift;
+       my $tarball=shift;
        
        my $branch="pristine-tar";
        my $deltafile=basename($tarball).".delta";
@@ -518,15 +558,10 @@ sub commit {
        my $tarball=shift;
        my $upstream=(@_ ? shift : "upstream");
 
-       my ($sourcedir, $id)=export($upstream);
        my $tempdir=tempdir();
+       my ($sourcedir, $id)=export($upstream);
        genmanifest($tarball, "$tempdir/manifest");
-       recreatetarball($tempdir, $sourcedir, clobber_source => 1,
-               # Set this because revision control systems may
-               # omit empty directories or the like.
-               # (A side effect is that, if $upstream is incomplete,
-               # the delta may become large.)
-               create_missing => 1);
+       recreatetarball($tempdir, $sourcedir, clobber_source => 1);
        my $pid = open(GENDELTA, "-|");
        if (! $pid) {
                # child
@@ -536,13 +571,27 @@ sub commit {
        local $/=undef;
        my $delta=<GENDELTA>;
        close GENDELTA || error "failed to generate delta";
-       savedelta($delta, $tarball, $id);
+       commitdelta($delta, $id, $tarball);
 }
 
 sub checkout {
        my $tarball=shift;
        
        my $tempdir=tempdir();
+       my ($delta, $id)=checkoutdelta($tarball);
+       my ($sourcedir, undef)=export($id);
+       my $pid = open(GENTAR, "|-");
+       if (! $pid) {
+               # child
+               $tarball=abs_path($tarball);
+               chdir($sourcedir) || die "chdir $sourcedir: $!";
+               gentar("-", $tarball, clobber_source => 1);
+               exit 0;
+       }
+       print GENTAR $delta;
+       close GENTAR || error "failed to generate tarball";
+
+       message("successfully generated $tarball");
 }
 
 Getopt::Long::Configure("bundling");
@@ -553,13 +602,15 @@ if (! GetOptions(
        usage();
 }
 
+usage unless @ARGV;
 my $command=shift;
+
 if ($command eq 'gentar') {
-       usage unless @ARGV == 3;
+       usage unless @ARGV == 2;
        gentar(@ARGV);
 }
 elsif ($command eq 'gendelta') {
-       usage unless @ARGV == 3;
+       usage unless @ARGV == 2;
        gendelta(@ARGV);
 }
 elsif ($command eq 'commit') {