# The basic idea is to walk the output of tla abrowse,
# fetch the changesets and apply them.
#
+
=head1 Invocation
- git-archimport -i <archive>/<branch> [<archive>/<branch>]
- [ <archive>/<branch> ]
+ git-archimport [ -h ] [ -v ] [ -T ] [ -t tempdir ] <archive>/<branch> [ <archive>/<branch> ]
- The script expects you to provide the key roots where it can start the
- import from an 'initial import' or 'tag' type of Arch commit. It will
- then follow all the branching and tagging within the provided roots.
+Imports a project from one or more Arch repositories. It will follow branches
+and repositories within the namespaces defined by the <archive/branch>
+parameters suppplied. If it cannot find the remote branch a merge comes from
+it will just import it as a regular commit. If it can find it, it will mark it
+as a merge whenever possible.
- It will die if it sees branches that have different roots.
+See man (1) git-archimport for more details.
-=head2 TODO
+=head1 TODO
- - keep track of merged patches, and mark a git merge when it happens
- - smarter rules to parse the archive history "up" and "down"
- - be able to continue an import where we left off
+ - create tag objects instead of ref tags
- audit shell-escaping of filenames
+ - hide our private tags somewhere smarter
+ - find a way to make "cat *patches | patch" safe even when patchfiles are missing newlines
=head1 Devel tricks
Add print in front of the shell commands invoked via backticks.
+=head1 Devel Notes
+
+There are several places where Arch and git terminology are intermixed
+and potentially confused.
+
+The notion of a "branch" in git is approximately equivalent to
+a "archive/category--branch--version" in Arch. Also, it should be noted
+that the "--branch" portion of "archive/category--branch--version" is really
+optional in Arch although not many people (nor tools!) seem to know this.
+This means that "archive/category--version" is also a valid "branch"
+in git terms.
+
+We always refer to Arch names by their fully qualified variant (which
+means the "archive" name is prefixed.
+
+For people unfamiliar with Arch, an "archive" is the term for "repository",
+and can contain multiple, unrelated branches.
+
=cut
use strict;
use warnings;
use Getopt::Std;
use File::Spec;
-use File::Temp qw(tempfile);
+use File::Temp qw(tempfile tempdir);
use File::Path qw(mkpath);
use File::Basename qw(basename dirname);
use String::ShellQuote;
$SIG{'PIPE'}="IGNORE";
$ENV{'TZ'}="UTC";
+my $git_dir = $ENV{"GIT_DIR"} || ".git";
+$ENV{"GIT_DIR"} = $git_dir;
+my $ptag_dir = "$git_dir/archimport/tags";
+
our($opt_h,$opt_v, $opt_T,
$opt_C,$opt_t);
sub usage() {
print STDERR <<END;
Usage: ${\basename $0} # fetch/update GIT from Arch
- [ -h ] [ -v ] [ -T ]
- [ -C GIT_repository ] [ -t tempdir ]
+ [ -h ] [ -v ] [ -T ] [ -t tempdir ]
repository/arch-branch [ repository/arch-branch] ...
END
exit(1);
}
-getopts("hviC:t:") or usage();
+getopts("Thvt:") or usage();
usage if $opt_h;
@ARGV >= 1 or usage();
my @arch_roots = @ARGV;
-my $tmp = $opt_t;
-$tmp ||= '/tmp';
-$tmp .= '/git-archimport/';
-
-my $git_tree = $opt_C;
-$git_tree ||= ".";
-
+my ($tmpdir, $tmpdirname) = tempdir('git-archimport-XXXXXX', TMPDIR => 1, CLEANUP => 1);
+my $tmp = $opt_t || 1;
+$tmp = tempdir('git-archimport-XXXXXX', TMPDIR => 1, CLEANUP => 1);
+$opt_v && print "+ Using $tmp as temporary directory\n";
my @psets = (); # the collection
+my %psets = (); # the collection, by name
+
+my %rptags = (); # my reverse private tags
+ # to map a SHA1 to a commitid
foreach my $root (@arch_roots) {
my ($arepo, $abranch) = split(m!/!, $root);
if (%ps) {
my %temp = %ps; # break references
push (@psets, \%temp);
+ $psets{$temp{id}} = \%temp;
%ps = ();
}
if (%ps) {
my %temp = %ps; # break references
- push (@psets, \%temp);
+ push (@psets, \%temp);
+ $psets{ $temp{id} } = \%temp;
%ps = ();
}
close ABROWSE;
## and put an initial import
## or a full tag
my $import = 0;
-unless (-d '.git') { # initial import
+unless (-d $git_dir) { # initial import
if ($psets[0]{type} eq 'i' || $psets[0]{type} eq 't') {
print "Starting import from $psets[0]{id}\n";
`git-init-db`;
} else {
die "Need to start from an import or a tag -- cannot use $psets[0]{id}";
}
+} else { # progressing an import
+ # load the rptags
+ opendir(DIR, "$git_dir/archimport/tags")
+ || die "can't opendir: $!";
+ while (my $file = readdir(DIR)) {
+ # skip non-interesting-files
+ next unless -f "$ptag_dir/$file";
+
+ # convert first '--' to '/' from old git-archimport to use
+ # as an archivename/c--b--v private tag
+ if ($file !~ m!,!) {
+ my $oldfile = $file;
+ $file =~ s!--!,!;
+ print STDERR "converting old tag $oldfile to $file\n";
+ rename("$ptag_dir/$oldfile", "$ptag_dir/$file") or die $!;
+ }
+ my $sha = ptag($file);
+ chomp $sha;
+ $rptags{$sha} = $file;
+ }
+ closedir DIR;
}
# process patchsets
-foreach my $ps (@psets) {
+# extract the Arch repository name (Arch "archive" in Arch-speak)
+sub extract_reponame {
+ my $fq_cvbr = shift; # archivename/[[[[category]branch]version]revision]
+ return (split(/\//, $fq_cvbr))[0];
+}
+
+sub extract_versionname {
+ my $name = shift;
+ $name =~ s/--(?:patch|version(?:fix)?|base)-\d+$//;
+ return $name;
+}
- $ps->{branch} = branchname($ps->{id});
+# convert a fully-qualified revision or version to a unique dirname:
+# normalperson@yhbt.net-05/mpd--uclinux--1--patch-2
+# becomes: normalperson@yhbt.net-05,mpd--uclinux--1
+#
+# the git notion of a branch is closer to
+# archive/category--branch--version than archive/category--branch, so we
+# use this to convert to git branch names.
+# Also, keep archive names but replace '/' with ',' since it won't require
+# subdirectories, and is safer than swapping '--' which could confuse
+# reverse-mapping when dealing with bastard branches that
+# are just archive/category--version (no --branch)
+sub tree_dirname {
+ my $revision = shift;
+ my $name = extract_versionname($revision);
+ $name =~ s#/#,#;
+ return $name;
+}
+
+*git_branchname = *tree_dirname;
+
+# process patchsets
+foreach my $ps (@psets) {
+ $ps->{branch} = git_branchname($ps->{id});
#
# ensure we have a clean state
# skip commits already in repo
#
if (ptag($ps->{id})) {
- $opt_v && print "Skipping already imported: $ps->{id}\n";
+ $opt_v && print " * Skipping already imported: $ps->{id}\n";
next;
}
+ print " * Starting to work on $ps->{id}\n";
+
#
# create the branch if needed
#
}
unless ($import) { # skip for import
- if ( -e ".git/refs/heads/$ps->{branch}") {
+ if ( -e "$git_dir/refs/heads/$ps->{branch}") {
# we know about this branch
`git checkout $ps->{branch}`;
} else {
# imports don't give us good info
# on added files. Shame on them
if ($ps->{type} eq 'i' || $ps->{type} eq 't') {
- `find . -type f -print0 | grep -zv '^./.git' | xargs -0 -l100 git-update-index --add`;
+ `find . -type f -print0 | grep -zv '^./$git_dir' | xargs -0 -l100 git-update-index --add`;
`git-ls-files --deleted -z | xargs --no-run-if-empty -0 -l100 git-update-index --remove`;
}
# Who's your daddy?
#
my @par;
- if ( -e ".git/refs/heads/$ps->{branch}") {
- if (open HEAD, "<.git/refs/heads/$ps->{branch}") {
+ if ( -e "$git_dir/refs/heads/$ps->{branch}") {
+ if (open HEAD, "<$git_dir/refs/heads/$ps->{branch}") {
my $p = <HEAD>;
close HEAD;
chomp $p;
}
}
+ if ($ps->{merges}) {
+ push @par, find_parents($ps);
+ }
my $par = join (' ', @par);
#
#
# Update the branch
#
- open HEAD, ">.git/refs/heads/$ps->{branch}";
+ open HEAD, ">$git_dir/refs/heads/$ps->{branch}";
print HEAD $commitid;
close HEAD;
- unlink ('.git/HEAD');
- symlink("refs/heads/$ps->{branch}",".git/HEAD");
+ system('git-update-ref', 'HEAD', "$ps->{branch}");
# tag accordingly
ptag($ps->{id}, $commitid); # private tag
print " * Committed $ps->{id}\n";
print " + tree $tree\n";
print " + commit $commitid\n";
- # print " + commit date is $ps->{date} \n";
-}
-
-sub branchname {
- my $id = shift;
- $id =~ s#^.+?/##;
- my @parts = split(m/--/, $id);
- return join('--', @parts[0..1]);
+ $opt_v && print " + commit date is $ps->{date} \n";
+ $opt_v && print " + parents: $par \n";
}
sub apply_import {
my $ps = shift;
- my $bname = branchname($ps->{id});
+ my $bname = git_branchname($ps->{id});
`mkdir -p $tmp`;
`tla get -s --no-pristine -A $ps->{repo} $ps->{id} $tmp/import`;
die "Cannot get import: $!" if $?;
- `rsync -v --archive --delete --exclude '.git' --exclude '.arch-ids' --exclude '{arch}' $tmp/import/* ./`;
+ `rsync -v --archive --delete --exclude '$git_dir' --exclude '.arch-ids' --exclude '{arch}' $tmp/import/* ./`;
die "Cannot rsync import:$!" if $?;
`rm -fr $tmp/import`;
}
# bring in new files
- `rsync --archive --exclude '.git' --exclude '.arch-ids' --exclude '{arch}' $tmp/changeset/new-files-archive/* ./`;
+ `rsync --archive --exclude '$git_dir' --exclude '.arch-ids' --exclude '{arch}' $tmp/changeset/new-files-archive/* ./`;
# deleted files are hinted from the commitlog processing
next if $t =~ m!\{arch\}/!;
next if $t =~ m!\.arch-ids/!;
next if $t =~ m!\.arch-inventory$!;
+ # tla cat-archive-log will give us filenames with spaces as file\(sp)name - why?
+ # we can assume that any filename with \ indicates some pika escaping that we want to get rid of.
+ if ($t =~ /\\/ ){
+ $t = `tla escape --unescaped '$t'`;
+ }
push (@tmp, shell_quote($t));
}
@$ref = @tmp;
# write/read a tag
sub tag {
my ($tag, $commit) = @_;
- $tag =~ s|/|--|g;
- $tag = shell_quote($tag);
+
+ # don't use subdirs for tags yet, it could screw up other porcelains
+ $tag =~ s|/|,|;
if ($commit) {
- open(C,">.git/refs/tags/$tag")
+ open(C,">","$git_dir/refs/tags/$tag")
or die "Cannot create tag $tag: $!\n";
print C "$commit\n"
or die "Cannot write tag $tag: $!\n";
close(C)
or die "Cannot write tag $tag: $!\n";
- print "Created tag '$tag' on '$commit'\n" if $opt_v;
+ print " * Created tag '$tag' on '$commit'\n" if $opt_v;
} else { # read
- open(C,"<.git/refs/tags/$tag")
+ open(C,"<","$git_dir/refs/tags/$tag")
or die "Cannot read tag $tag: $!\n";
$commit = <C>;
chomp $commit;
# reads fail softly if the tag isn't there
sub ptag {
my ($tag, $commit) = @_;
- $tag =~ s|/|--|g;
- $tag = shell_quote($tag);
+
+ # don't use subdirs for tags yet, it could screw up other porcelains
+ $tag =~ s|/|,|g;
- unless (-d '.git/archimport/tags') {
- mkpath('.git/archimport/tags');
- }
+ my $tag_file = "$ptag_dir/$tag";
+ my $tag_branch_dir = dirname($tag_file);
+ mkpath($tag_branch_dir) unless (-d $tag_branch_dir);
if ($commit) { # write
- open(C,">.git/archimport/tags/$tag")
+ open(C,">",$tag_file)
or die "Cannot create tag $tag: $!\n";
print C "$commit\n"
or die "Cannot write tag $tag: $!\n";
close(C)
or die "Cannot write tag $tag: $!\n";
+ $rptags{$commit} = $tag
+ unless $tag =~ m/--base-0$/;
} else { # read
# if the tag isn't there, return 0
- unless ( -s ".git/archimport/tags/$tag") {
+ unless ( -s $tag_file) {
return 0;
}
- open(C,"<.git/archimport/tags/$tag")
+ open(C,"<",$tag_file)
or die "Cannot read tag $tag: $!\n";
$commit = <C>;
chomp $commit;
die "Error reading tag $tag: $!\n" unless length $commit == 40;
close(C)
or die "Cannot read tag $tag: $!\n";
+ unless (defined $rptags{$commit}) {
+ $rptags{$commit} = $tag;
+ }
return $commit;
}
}
+
+sub find_parents {
+ #
+ # Identify what branches are merging into me
+ # and whether we are fully merged
+ # git-merge-base <headsha> <headsha> should tell
+ # me what the base of the merge should be
+ #
+ my $ps = shift;
+
+ my %branches; # holds an arrayref per branch
+ # the arrayref contains a list of
+ # merged patches between the base
+ # of the merge and the current head
+
+ my @parents; # parents found for this commit
+
+ # simple loop to split the merges
+ # per branch
+ foreach my $merge (@{$ps->{merges}}) {
+ my $branch = git_branchname($merge);
+ unless (defined $branches{$branch} ){
+ $branches{$branch} = [];
+ }
+ push @{$branches{$branch}}, $merge;
+ }
+
+ #
+ # foreach branch find a merge base and walk it to the
+ # head where we are, collecting the merged patchsets that
+ # Arch has recorded. Keep that in @have
+ # Compare that with the commits on the other branch
+ # between merge-base and the tip of the branch (@need)
+ # and see if we have a series of consecutive patches
+ # starting from the merge base. The tip of the series
+ # of consecutive patches merged is our new parent for
+ # that branch.
+ #
+ foreach my $branch (keys %branches) {
+
+ # check that we actually know about the branch
+ next unless -e "$git_dir/refs/heads/$branch";
+
+ my $mergebase = `git-merge-base $branch $ps->{branch}`;
+ if ($?) {
+ # Don't die here, Arch supports one-way cherry-picking
+ # between branches with no common base (or any relationship
+ # at all beforehand)
+ warn "Cannot find merge base for $branch and $ps->{branch}";
+ next;
+ }
+ chomp $mergebase;
+
+ # now walk up to the mergepoint collecting what patches we have
+ my $branchtip = git_rev_parse($ps->{branch});
+ my @ancestors = `git-rev-list --merge-order $branchtip ^$mergebase`;
+ my %have; # collected merges this branch has
+ foreach my $merge (@{$ps->{merges}}) {
+ $have{$merge} = 1;
+ }
+ my %ancestorshave;
+ foreach my $par (@ancestors) {
+ $par = commitid2pset($par);
+ if (defined $par->{merges}) {
+ foreach my $merge (@{$par->{merges}}) {
+ $ancestorshave{$merge}=1;
+ }
+ }
+ }
+ # print "++++ Merges in $ps->{id} are....\n";
+ # my @have = sort keys %have; print Dumper(\@have);
+
+ # merge what we have with what ancestors have
+ %have = (%have, %ancestorshave);
+
+ # see what the remote branch has - these are the merges we
+ # will want to have in a consecutive series from the mergebase
+ my $otherbranchtip = git_rev_parse($branch);
+ my @needraw = `git-rev-list --merge-order $otherbranchtip ^$mergebase`;
+ my @need;
+ foreach my $needps (@needraw) { # get the psets
+ $needps = commitid2pset($needps);
+ # git-rev-list will also
+ # list commits merged in via earlier
+ # merges. we are only interested in commits
+ # from the branch we're looking at
+ if ($branch eq $needps->{branch}) {
+ push @need, $needps->{id};
+ }
+ }
+
+ # print "++++ Merges from $branch we want are....\n";
+ # print Dumper(\@need);
+
+ my $newparent;
+ while (my $needed_commit = pop @need) {
+ if ($have{$needed_commit}) {
+ $newparent = $needed_commit;
+ } else {
+ last; # break out of the while
+ }
+ }
+ if ($newparent) {
+ push @parents, $newparent;
+ }
+
+
+ } # end foreach branch
+
+ # prune redundant parents
+ my %parents;
+ foreach my $p (@parents) {
+ $parents{$p} = 1;
+ }
+ foreach my $p (@parents) {
+ next unless exists $psets{$p}{merges};
+ next unless ref $psets{$p}{merges};
+ my @merges = @{$psets{$p}{merges}};
+ foreach my $merge (@merges) {
+ if ($parents{$merge}) {
+ delete $parents{$merge};
+ }
+ }
+ }
+ @parents = keys %parents;
+ @parents = map { " -p " . ptag($_) } @parents;
+ return @parents;
+}
+
+sub git_rev_parse {
+ my $name = shift;
+ my $val = `git-rev-parse $name`;
+ die "Error: git-rev-parse $name" if $?;
+ chomp $val;
+ return $val;
+}
+
+# resolve a SHA1 to a known patchset
+sub commitid2pset {
+ my $commitid = shift;
+ chomp $commitid;
+ my $name = $rptags{$commitid}
+ || die "Cannot find reverse tag mapping for $commitid";
+ $name =~ s|,|/|;
+ my $ps = $psets{$name}
+ || (print Dumper(sort keys %psets)) && die "Cannot find patchset for $name";
+ return $ps;
+}