git-archimport.perl

   1 #!/usr/bin/perl
   2 #
   3 # This tool is copyright (c) 2005, Martin Langhoff.
   4 # It is released under the Gnu Public License, version 2.
   5 #
   6 # The basic idea is to walk the output of tla abrowse,
   7 # fetch the changesets and apply them.
   8 #
   9
  10 =head1 Invocation
  11
  12     git archimport [ -h ] [ -v ] [ -o ] [ -a ] [ -f ] [ -T ]
  13         [ -D depth] [ -t tempdir ] <archive>/<branch> [ <archive>/<branch> ]
  14
  15 Imports a project from one or more Arch repositories. It will follow branches
  16 and repositories within the namespaces defined by the <archive/branch>
  17 parameters supplied. If it cannot find the remote branch a merge comes from
  18 it will just import it as a regular commit. If it can find it, it will mark it
  19 as a merge whenever possible.
  20
  21 See man (1) git-archimport for more details.
  22
  23 =head1 TODO
  24
  25  - create tag objects instead of ref tags
  26  - audit shell-escaping of filenames
  27  - hide our private tags somewhere smarter
  28  - find a way to make "cat *patches | patch" safe even when patchfiles are missing newlines
  29  - sort and apply patches by graphing ancestry relations instead of just
  30    relying in dates supplied in the changeset itself.
  31    tla ancestry-graph -m could be helpful here...
  32
  33 =head1 Devel tricks
  34
  35 Add print in front of the shell commands invoked via backticks.
  36
  37 =head1 Devel Notes
  38
  39 There are several places where Arch and git terminology are intermixed
  40 and potentially confused.
  41
  42 The notion of a "branch" in git is approximately equivalent to
  43 a "archive/category--branch--version" in Arch.  Also, it should be noted
  44 that the "--branch" portion of "archive/category--branch--version" is really
  45 optional in Arch although not many people (nor tools!) seem to know this.
  46 This means that "archive/category--version" is also a valid "branch"
  47 in git terms.
  48
  49 We always refer to Arch names by their fully qualified variant (which
  50 means the "archive" name is prefixed.
  51
  52 For people unfamiliar with Arch, an "archive" is the term for "repository",
  53 and can contain multiple, unrelated branches.
  54
  55 =cut
  56
  57 use 5.008;
  58 use strict;
  59 use warnings;
  60 use Getopt::Std;
  61 use File::Temp qw(tempdir);
  62 use File::Path qw(mkpath rmtree);
  63 use File::Basename qw(basename dirname);
  64 use Data::Dumper qw/ Dumper /;
  65 use IPC::Open2;
  66
  67 $SIG{'PIPE'}="IGNORE";
  68 $ENV{'TZ'}="UTC";
  69
  70 my $git_dir = $ENV{"GIT_DIR"} || ".git";
  71 $ENV{"GIT_DIR"} = $git_dir;
  72 my $ptag_dir = "$git_dir/archimport/tags";
  73
  74 our($opt_h,$opt_f,$opt_v,$opt_T,$opt_t,$opt_D,$opt_a,$opt_o);
  75
  76 sub usage() {
  77     print STDERR <<END;
  78 usage: git archimport     # fetch/update GIT from Arch
  79        [ -h ] [ -v ] [ -o ] [ -a ] [ -f ] [ -T ] [ -D depth ] [ -t tempdir ]
  80        repository/arch-branch [ repository/arch-branch] ...
  81 END
  82     exit(1);
  83 }
  84
  85 getopts("fThvat:D:") or usage();
  86 usage if $opt_h;
  87
  88 @ARGV >= 1 or usage();
  89 # $arch_branches:
  90 # values associated with keys:
  91 #   =1 - Arch version / git 'branch' detected via abrowse on a limit
  92 #   >1 - Arch version / git 'branch' of an auxiliary branch we've merged
  93 my %arch_branches = map { my $branch = $_; $branch =~ s/:[^:]*$//; $branch => 1 } @ARGV;
  94
  95 # $branch_name_map:
  96 # maps arch branches to git branch names
  97 my %branch_name_map = map { m/^(.*):([^:]*)$/; $1 => $2 } grep { m/:/ } @ARGV;
  98
  99 $ENV{'TMPDIR'} = $opt_t if $opt_t; # $ENV{TMPDIR} will affect tempdir() calls:
 100 my $tmp = tempdir('git-archimport-XXXXXX', TMPDIR => 1, CLEANUP => 1);
 101 $opt_v && print "+ Using $tmp as temporary directory\n";
 102
 103 unless (-d $git_dir) { # initial import needs empty directory
 104     opendir DIR, '.' or die "Unable to open current directory: $!\n";
 105     while (my $entry = readdir DIR) {
 106         $entry =~ /^\.\.?$/ or
 107             die "Initial import needs an empty current working directory.\n"
 108     }
 109     closedir DIR
 110 }
 111
 112 my $default_archive;            # default Arch archive
 113 my %reachable = ();             # Arch repositories we can access
 114 my %unreachable = ();           # Arch repositories we can't access :<
 115 my @psets  = ();                # the collection
 116 my %psets  = ();                # the collection, by name
 117 my %stats  = (                  # Track which strategy we used to import:
 118         get_tag => 0, replay => 0, get_new => 0, get_delta => 0,
 119         simple_changeset => 0, import_or_tag => 0
 120 );
 121
 122 my %rptags = ();                # my reverse private tags
 123                                 # to map a SHA1 to a commitid
 124 my $TLA = $ENV{'ARCH_CLIENT'} || 'tla';
 125
 126 sub do_abrowse {
 127     my $stage = shift;
 128     while (my ($limit, $level) = each %arch_branches) {
 129         next unless $level == $stage;
 130
 131         open ABROWSE, "$TLA abrowse -fkD --merges $limit |"
 132                                 or die "Problems with tla abrowse: $!";
 133
 134         my %ps        = ();         # the current one
 135         my $lastseen  = '';
 136
 137         while (<ABROWSE>) {
 138             chomp;
 139
 140             # first record padded w 8 spaces
 141             if (s/^\s{8}\b//) {
 142                 my ($id, $type) = split(m/\s+/, $_, 2);
 143
 144                 my %last_ps;
 145                 # store the record we just captured
 146                 if (%ps && !exists $psets{ $ps{id} }) {
 147                     %last_ps = %ps; # break references
 148                     push (@psets, \%last_ps);
 149                     $psets{ $last_ps{id} } = \%last_ps;
 150                 }
 151
 152                 my $branch = extract_versionname($id);
 153                 %ps = ( id => $id, branch => $branch );
 154                 if (%last_ps && ($last_ps{branch} eq $branch)) {
 155                     $ps{parent_id} = $last_ps{id};
 156                 }
 157
 158                 $arch_branches{$branch} = 1;
 159                 $lastseen = 'id';
 160
 161                 # deal with types (should work with baz or tla):
 162                 if ($type =~ m/\(.*changeset\)/) {
 163                     $ps{type} = 's';
 164                 } elsif ($type =~ /\(.*import\)/) {
 165                     $ps{type} = 'i';
 166                 } elsif ($type =~ m/\(tag.*?(\S+\@\S+).*?\)/) {
 167                     $ps{type} = 't';
 168                     # read which revision we've tagged when we parse the log
 169                     $ps{tag}  = $1;
 170                 } else {
 171                     warn "Unknown type $type";
 172                 }
 173
 174                 $arch_branches{$branch} = 1;
 175                 $lastseen = 'id';
 176             } elsif (s/^\s{10}//) {
 177                 # 10 leading spaces or more
 178                 # indicate commit metadata
 179
 180                 # date
 181                 if ($lastseen eq 'id' && m/^(\d{4}-\d\d-\d\d \d\d:\d\d:\d\d)/){
 182                     $ps{date}   = $1;
 183                     $lastseen = 'date';
 184                 } elsif ($_ eq 'merges in:') {
 185                     $ps{merges} = [];
 186                     $lastseen = 'merges';
 187                 } elsif ($lastseen eq 'merges' && s/^\s{2}//) {
 188                     my $id = $_;
 189                     push (@{$ps{merges}}, $id);
 190
 191                     # aggressive branch finding:
 192                     if ($opt_D) {
 193                         my $branch = extract_versionname($id);
 194                         my $repo = extract_reponame($branch);
 195
 196                         if (archive_reachable($repo) &&
 197                                 !defined $arch_branches{$branch}) {
 198                             $arch_branches{$branch} = $stage + 1;
 199                         }
 200                     }
 201                 } else {
 202                     warn "more metadata after merges!?: $_\n" unless /^\s*$/;
 203                 }
 204             }
 205         }
 206
 207         if (%ps && !exists $psets{ $ps{id} }) {
 208             my %temp = %ps;         # break references
 209             if (@psets && $psets[$#psets]{branch} eq $ps{branch}) {
 210                 $temp{parent_id} = $psets[$#psets]{id};
 211             }
 212             push (@psets, \%temp);
 213             $psets{ $temp{id} } = \%temp;
 214         }
 215
 216         close ABROWSE or die "$TLA abrowse failed on $limit\n";
 217     }
 218 }                               # end foreach $root
 219
 220 do_abrowse(1);
 221 my $depth = 2;
 222 $opt_D ||= 0;
 223 while ($depth <= $opt_D) {
 224     do_abrowse($depth);
 225     $depth++;
 226 }
 227
 228 ## Order patches by time
 229 # FIXME see if we can find a more optimal way to do this by graphing
 230 # the ancestry data and walking it, that way we won't have to rely on
 231 # client-supplied dates
 232 @psets = sort {$a->{date}.$b->{id} cmp $b->{date}.$b->{id}} @psets;
 233
 234 #print Dumper \@psets;
 235
 236 ##
 237 ## TODO cleanup irrelevant patches
 238 ##      and put an initial import
 239 ##      or a full tag
 240 my $import = 0;
 241 unless (-d $git_dir) { # initial import
 242     if ($psets[0]{type} eq 'i' || $psets[0]{type} eq 't') {
 243         print "Starting import from $psets[0]{id}\n";
 244         `git-init`;
 245         die $! if $?;
 246         $import = 1;
 247     } else {
 248         die "Need to start from an import or a tag -- cannot use $psets[0]{id}";
 249     }
 250 } else {    # progressing an import
 251     # load the rptags
 252     opendir(DIR, $ptag_dir)
 253         || die "can't opendir: $!";
 254     while (my $file = readdir(DIR)) {
 255         # skip non-interesting-files
 256         next unless -f "$ptag_dir/$file";
 257
 258         # convert first '--' to '/' from old git-archimport to use
 259         # as an archivename/c--b--v private tag
 260         if ($file !~ m!,!) {
 261             my $oldfile = $file;
 262             $file =~ s!--!,!;
 263             print STDERR "converting old tag $oldfile to $file\n";
 264             rename("$ptag_dir/$oldfile", "$ptag_dir/$file") or die $!;
 265         }
 266         my $sha = ptag($file);
 267         chomp $sha;
 268         $rptags{$sha} = $file;
 269     }
 270     closedir DIR;
 271 }
 272
 273 # process patchsets
 274 # extract the Arch repository name (Arch "archive" in Arch-speak)
 275 sub extract_reponame {
 276     my $fq_cvbr = shift; # archivename/[[[[category]branch]version]revision]
 277     return (split(/\//, $fq_cvbr))[0];
 278 }
 279
 280 sub extract_versionname {
 281     my $name = shift;
 282     $name =~ s/--(?:patch|version(?:fix)?|base)-\d+$//;
 283     return $name;
 284 }
 285
 286 # convert a fully-qualified revision or version to a unique dirname:
 287 #   normalperson@yhbt.net-05/mpd--uclinux--1--patch-2
 288 # becomes: normalperson@yhbt.net-05,mpd--uclinux--1
 289 #
 290 # the git notion of a branch is closer to
 291 # archive/category--branch--version than archive/category--branch, so we
 292 # use this to convert to git branch names.
 293 # Also, keep archive names but replace '/' with ',' since it won't require
 294 # subdirectories, and is safer than swapping '--' which could confuse
 295 # reverse-mapping when dealing with bastard branches that
 296 # are just archive/category--version  (no --branch)
 297 sub tree_dirname {
 298     my $revision = shift;
 299     my $name = extract_versionname($revision);
 300     $name =~ s#/#,#;
 301     return $name;
 302 }
 303
 304 # old versions of git-archimport just use the <category--branch> part:
 305 sub old_style_branchname {
 306     my $id = shift;
 307     my $ret = safe_pipe_capture($TLA,'parse-package-name','-p',$id);
 308     chomp $ret;
 309     return $ret;
 310 }
 311
 312 *git_default_branchname = $opt_o ? *old_style_branchname : *tree_dirname;
 313
 314 # retrieve default archive, since $branch_name_map keys might not include it
 315 sub get_default_archive {
 316     if (!defined $default_archive) {
 317         $default_archive = safe_pipe_capture($TLA,'my-default-archive');
 318         chomp $default_archive;
 319     }
 320     return $default_archive;
 321 }
 322
 323 sub git_branchname {
 324     my $revision = shift;
 325     my $name = extract_versionname($revision);
 326
 327     if (exists $branch_name_map{$name}) {
 328         return $branch_name_map{$name};
 329
 330     } elsif ($name =~ m#^([^/]*)/(.*)$#
 331              && $1 eq get_default_archive()
 332              && exists $branch_name_map{$2}) {
 333         # the names given in the command-line lacked the archive.
 334         return $branch_name_map{$2};
 335
 336     } else {
 337         return git_default_branchname($revision);
 338     }
 339 }
 340
 341 sub process_patchset_accurate {
 342     my $ps = shift;
 343
 344     # switch to that branch if we're not already in that branch:
 345     if (-e "$git_dir/refs/heads/$ps->{branch}") {
 346        system('git-checkout','-f',$ps->{branch}) == 0 or die "$! $?\n";
 347
 348        # remove any old stuff that got leftover:
 349        my $rm = safe_pipe_capture('git-ls-files','--others','-z');
 350        rmtree(split(/\0/,$rm)) if $rm;
 351     }
 352
 353     # Apply the import/changeset/merge into the working tree
 354     my $dir = sync_to_ps($ps);
 355     # read the new log entry:
 356     my @commitlog = safe_pipe_capture($TLA,'cat-log','-d',$dir,$ps->{id});
 357     die "Error in cat-log: $!" if $?;
 358     chomp @commitlog;
 359
 360     # grab variables we want from the log, new fields get added to $ps:
 361     # (author, date, email, summary, message body ...)
 362     parselog($ps, \@commitlog);
 363
 364     if ($ps->{id} =~ /--base-0$/ && $ps->{id} ne $psets[0]{id}) {
 365         # this should work when importing continuations
 366         if ($ps->{tag} && (my $branchpoint = eval { ptag($ps->{tag}) })) {
 367
 368             # find where we are supposed to branch from
 369             if (! -e "$git_dir/refs/heads/$ps->{branch}") {
 370                 system('git-branch',$ps->{branch},$branchpoint) == 0 or die "$! $?\n";
 371
 372                 # We trust Arch with the fact that this is just a tag,
 373                 # and it does not affect the state of the tree, so
 374                 # we just tag and move on.  If the user really wants us
 375                 # to consolidate more branches into one, don't tag because
 376                 # the tag name would be already taken.
 377                 tag($ps->{id}, $branchpoint);
 378                 ptag($ps->{id}, $branchpoint);
 379                 print " * Tagged $ps->{id} at $branchpoint\n";
 380             }
 381             system('git-checkout','-f',$ps->{branch}) == 0 or die "$! $?\n";
 382
 383             # remove any old stuff that got leftover:
 384             my $rm = safe_pipe_capture('git-ls-files','--others','-z');
 385             rmtree(split(/\0/,$rm)) if $rm;
 386             return 0;
 387         } else {
 388             warn "Tagging from unknown id unsupported\n" if $ps->{tag};
 389         }
 390         # allow multiple bases/imports here since Arch supports cherry-picks
 391         # from unrelated trees
 392     }
 393
 394     # update the index with all the changes we got
 395     system('git-diff-files --name-only -z | '.
 396             'git-update-index --remove -z --stdin') == 0 or die "$! $?\n";
 397     system('git-ls-files --others -z | '.
 398             'git-update-index --add -z --stdin') == 0 or die "$! $?\n";
 399     return 1;
 400 }
 401
 402 # the native changeset processing strategy.  This is very fast, but
 403 # does not handle permissions or any renames involving directories
 404 sub process_patchset_fast {
 405     my $ps = shift;
 406     #
 407     # create the branch if needed
 408     #
 409     if ($ps->{type} eq 'i' && !$import) {
 410         die "Should not have more than one 'Initial import' per GIT import: $ps->{id}";
 411     }
 412
 413     unless ($import) { # skip for import
 414         if ( -e "$git_dir/refs/heads/$ps->{branch}") {
 415             # we know about this branch
 416             system('git-checkout',$ps->{branch});
 417         } else {
 418             # new branch! we need to verify a few things
 419             die "Branch on a non-tag!" unless $ps->{type} eq 't';
 420             my $branchpoint = ptag($ps->{tag});
 421             die "Tagging from unknown id unsupported: $ps->{tag}"
 422                 unless $branchpoint;
 423
 424             # find where we are supposed to branch from
 425             if (! -e "$git_dir/refs/heads/$ps->{branch}") {
 426                 system('git-branch',$ps->{branch},$branchpoint) == 0 or die "$! $?\n";
 427
 428                 # We trust Arch with the fact that this is just a tag,
 429                 # and it does not affect the state of the tree, so
 430                 # we just tag and move on.  If the user really wants us
 431                 # to consolidate more branches into one, don't tag because
 432                 # the tag name would be already taken.
 433                 tag($ps->{id}, $branchpoint);
 434                 ptag($ps->{id}, $branchpoint);
 435                 print " * Tagged $ps->{id} at $branchpoint\n";
 436             }
 437             system('git-checkout',$ps->{branch}) == 0 or die "$! $?\n";
 438             return 0;
 439         }
 440         die $! if $?;
 441     }
 442
 443     #
 444     # Apply the import/changeset/merge into the working tree
 445     #
 446     if ($ps->{type} eq 'i' || $ps->{type} eq 't') {
 447         apply_import($ps) or die $!;
 448         $stats{import_or_tag}++;
 449         $import=0;
 450     } elsif ($ps->{type} eq 's') {
 451         apply_cset($ps);
 452         $stats{simple_changeset}++;
 453     }
 454
 455     #
 456     # prepare update git's index, based on what arch knows
 457     # about the pset, resolve parents, etc
 458     #
 459
 460     my @commitlog = safe_pipe_capture($TLA,'cat-archive-log',$ps->{id});
 461     die "Error in cat-archive-log: $!" if $?;
 462
 463     parselog($ps,\@commitlog);
 464
 465     # imports don't give us good info
 466     # on added files. Shame on them
 467     if ($ps->{type} eq 'i' || $ps->{type} eq 't') {
 468         system('git-ls-files --deleted -z | '.
 469                 'git-update-index --remove -z --stdin') == 0 or die "$! $?\n";
 470         system('git-ls-files --others -z | '.
 471                 'git-update-index --add -z --stdin') == 0 or die "$! $?\n";
 472     }
 473
 474     # TODO: handle removed_directories and renamed_directories:
 475
 476     if (my $del = $ps->{removed_files}) {
 477         unlink @$del;
 478         while (@$del) {
 479             my @slice = splice(@$del, 0, 100);
 480             system('git-update-index','--remove','--',@slice) == 0 or
 481                             die "Error in git-update-index --remove: $! $?\n";
 482         }
 483     }
 484
 485     if (my $ren = $ps->{renamed_files}) {                # renamed
 486         if (@$ren % 2) {
 487             die "Odd number of entries in rename!?";
 488         }
 489
 490         while (@$ren) {
 491             my $from = shift @$ren;
 492             my $to   = shift @$ren;
 493
 494             unless (-d dirname($to)) {
 495                 mkpath(dirname($to)); # will die on err
 496             }
 497             # print "moving $from $to";
 498             rename($from, $to) or die "Error renaming '$from' '$to': $!\n";
 499             system('git-update-index','--remove','--',$from) == 0 or
 500                             die "Error in git-update-index --remove: $! $?\n";
 501             system('git-update-index','--add','--',$to) == 0 or
 502                             die "Error in git-update-index --add: $! $?\n";
 503         }
 504     }
 505
 506     if (my $add = $ps->{new_files}) {
 507         while (@$add) {
 508             my @slice = splice(@$add, 0, 100);
 509             system('git-update-index','--add','--',@slice) == 0 or
 510                             die "Error in git-update-index --add: $! $?\n";
 511         }
 512     }
 513
 514     if (my $mod = $ps->{modified_files}) {
 515         while (@$mod) {
 516             my @slice = splice(@$mod, 0, 100);
 517             system('git-update-index','--',@slice) == 0 or
 518                             die "Error in git-update-index: $! $?\n";
 519         }
 520     }
 521     return 1; # we successfully applied the changeset
 522 }
 523
 524 if ($opt_f) {
 525     print "Will import patchsets using the fast strategy\n",
 526             "Renamed directories and permission changes will be missed\n";
 527     *process_patchset = *process_patchset_fast;
 528 } else {
 529     print "Using the default (accurate) import strategy.\n",
 530             "Things may be a bit slow\n";
 531     *process_patchset = *process_patchset_accurate;
 532 }
 533
 534 foreach my $ps (@psets) {
 535     # process patchsets
 536     $ps->{branch} = git_branchname($ps->{id});
 537
 538     #
 539     # ensure we have a clean state
 540     #
 541     if (my $dirty = `git-diff-files`) {
 542         die "Unclean tree when about to process $ps->{id} " .
 543             " - did we fail to commit cleanly before?\n$dirty";
 544     }
 545     die $! if $?;
 546
 547     #
 548     # skip commits already in repo
 549     #
 550     if (ptag($ps->{id})) {
 551       $opt_v && print " * Skipping already imported: $ps->{id}\n";
 552       next;
 553     }
 554
 555     print " * Starting to work on $ps->{id}\n";
 556
 557     process_patchset($ps) or next;
 558
 559     # warn "errors when running git-update-index! $!";
 560     my $tree = `git-write-tree`;
 561     die "cannot write tree $!" if $?;
 562     chomp $tree;
 563
 564     #
 565     # Who's your daddy?
 566     #
 567     my @par;
 568     if ( -e "$git_dir/refs/heads/$ps->{branch}") {
 569         if (open HEAD, "<","$git_dir/refs/heads/$ps->{branch}") {
 570             my $p = <HEAD>;
 571             close HEAD;
 572             chomp $p;
 573             push @par, '-p', $p;
 574         } else {
 575             if ($ps->{type} eq 's') {
 576                 warn "Could not find the right head for the branch $ps->{branch}";
 577             }
 578         }
 579     }
 580
 581     if ($ps->{merges}) {
 582         push @par, find_parents($ps);
 583     }
 584
 585     #
 586     # Commit, tag and clean state
 587     #
 588     $ENV{TZ}                  = 'GMT';
 589     $ENV{GIT_AUTHOR_NAME}     = $ps->{author};
 590     $ENV{GIT_AUTHOR_EMAIL}    = $ps->{email};
 591     $ENV{GIT_AUTHOR_DATE}     = $ps->{date};
 592     $ENV{GIT_COMMITTER_NAME}  = $ps->{author};
 593     $ENV{GIT_COMMITTER_EMAIL} = $ps->{email};
 594     $ENV{GIT_COMMITTER_DATE}  = $ps->{date};
 595
 596     my $pid = open2(*READER, *WRITER,'git-commit-tree',$tree,@par)
 597         or die $!;
 598     print WRITER $ps->{summary},"\n\n";
 599
 600     # only print message if it's not empty, to avoid a spurious blank line;
 601     # also append an extra newline, so there's a blank line before the
 602     # following "git-archimport-id:" line.
 603     print WRITER $ps->{message},"\n\n" if ($ps->{message} ne "");
 604
 605     # make it easy to backtrack and figure out which Arch revision this was:
 606     print WRITER 'git-archimport-id: ',$ps->{id},"\n";
 607
 608     close WRITER;
 609     my $commitid = <READER>;    # read
 610     chomp $commitid;
 611     close READER;
 612     waitpid $pid,0;             # close;
 613
 614     if (length $commitid != 40) {
 615         die "Something went wrong with the commit! $! $commitid";
 616     }
 617     #
 618     # Update the branch
 619     #
 620     open  HEAD, ">","$git_dir/refs/heads/$ps->{branch}";
 621     print HEAD $commitid;
 622     close HEAD;
 623     system('git-update-ref', 'HEAD', "$ps->{branch}");
 624
 625     # tag accordingly
 626     ptag($ps->{id}, $commitid); # private tag
 627     if ($opt_T || $ps->{type} eq 't' || $ps->{type} eq 'i') {
 628         tag($ps->{id}, $commitid);
 629     }
 630     print " * Committed $ps->{id}\n";
 631     print "   + tree   $tree\n";
 632     print "   + commit $commitid\n";
 633     $opt_v && print "   + commit date is  $ps->{date} \n";
 634     $opt_v && print "   + parents:  ",join(' ',@par),"\n";
 635 }
 636
 637 if ($opt_v) {
 638     foreach (sort keys %stats) {
 639         print" $_: $stats{$_}\n";
 640     }
 641 }
 642 exit 0;
 643
 644 # used by the accurate strategy:
 645 sub sync_to_ps {
 646     my $ps = shift;
 647     my $tree_dir = $tmp.'/'.tree_dirname($ps->{id});
 648
 649     $opt_v && print "sync_to_ps($ps->{id}) method: ";
 650
 651     if (-d $tree_dir) {
 652         if ($ps->{type} eq 't') {
 653             $opt_v && print "get (tag)\n";
 654             # looks like a tag-only or (worse,) a mixed tags/changeset branch,
 655             # can't rely on replay to work correctly on these
 656             rmtree($tree_dir);
 657             safe_pipe_capture($TLA,'get','--no-pristine',$ps->{id},$tree_dir);
 658             $stats{get_tag}++;
 659         } else {
 660                 my $tree_id = arch_tree_id($tree_dir);
 661                 if ($ps->{parent_id} && ($ps->{parent_id} eq $tree_id)) {
 662                     # the common case (hopefully)
 663                     $opt_v && print "replay\n";
 664                     safe_pipe_capture($TLA,'replay','-d',$tree_dir,$ps->{id});
 665                     $stats{replay}++;
 666                 } else {
 667                     # getting one tree is usually faster than getting two trees
 668                     # and applying the delta ...
 669                     rmtree($tree_dir);
 670                     $opt_v && print "apply-delta\n";
 671                     safe_pipe_capture($TLA,'get','--no-pristine',
 672                                         $ps->{id},$tree_dir);
 673                     $stats{get_delta}++;
 674                 }
 675         }
 676     } else {
 677         # new branch work
 678         $opt_v && print "get (new tree)\n";
 679         safe_pipe_capture($TLA,'get','--no-pristine',$ps->{id},$tree_dir);
 680         $stats{get_new}++;
 681     }
 682
 683     # added -I flag to rsync since we're going to fast! AIEEEEE!!!!
 684     system('rsync','-aI','--delete','--exclude',$git_dir,
 685 #               '--exclude','.arch-inventory',
 686                 '--exclude','.arch-ids','--exclude','{arch}',
 687                 '--exclude','+*','--exclude',',*',
 688                 "$tree_dir/",'./') == 0 or die "Cannot rsync $tree_dir: $! $?";
 689     return $tree_dir;
 690 }
 691
 692 sub apply_import {
 693     my $ps = shift;
 694     my $bname = git_branchname($ps->{id});
 695
 696     mkpath($tmp);
 697
 698     safe_pipe_capture($TLA,'get','-s','--no-pristine',$ps->{id},"$tmp/import");
 699     die "Cannot get import: $!" if $?;
 700     system('rsync','-aI','--delete', '--exclude',$git_dir,
 701                 '--exclude','.arch-ids','--exclude','{arch}',
 702                 "$tmp/import/", './');
 703     die "Cannot rsync import:$!" if $?;
 704
 705     rmtree("$tmp/import");
 706     die "Cannot remove tempdir: $!" if $?;
 707
 708
 709     return 1;
 710 }
 711
 712 sub apply_cset {
 713     my $ps = shift;
 714
 715     mkpath($tmp);
 716
 717     # get the changeset
 718     safe_pipe_capture($TLA,'get-changeset',$ps->{id},"$tmp/changeset");
 719     die "Cannot get changeset: $!" if $?;
 720
 721     # apply patches
 722     if (`find $tmp/changeset/patches -type f -name '*.patch'`) {
 723         # this can be sped up considerably by doing
 724         #    (find | xargs cat) | patch
 725         # but that can get mucked up by patches
 726         # with missing trailing newlines or the standard
 727         # 'missing newline' flag in the patch - possibly
 728         # produced with an old/buggy diff.
 729         # slow and safe, we invoke patch once per patchfile
 730         `find $tmp/changeset/patches -type f -name '*.patch' -print0 | grep -zv '{arch}' | xargs -iFILE -0 --no-run-if-empty patch -p1 --forward -iFILE`;
 731         die "Problem applying patches! $!" if $?;
 732     }
 733
 734     # apply changed binary files
 735     if (my @modified = `find $tmp/changeset/patches -type f -name '*.modified'`) {
 736         foreach my $mod (@modified) {
 737             chomp $mod;
 738             my $orig = $mod;
 739             $orig =~ s/\.modified$//; # lazy
 740             $orig =~ s!^\Q$tmp\E/changeset/patches/!!;
 741             #print "rsync -p '$mod' '$orig'";
 742             system('rsync','-p',$mod,"./$orig");
 743             die "Problem applying binary changes! $!" if $?;
 744         }
 745     }
 746
 747     # bring in new files
 748     system('rsync','-aI','--exclude',$git_dir,
 749                 '--exclude','.arch-ids',
 750                 '--exclude', '{arch}',
 751                 "$tmp/changeset/new-files-archive/",'./');
 752
 753     # deleted files are hinted from the commitlog processing
 754
 755     rmtree("$tmp/changeset");
 756 }
 757
 758
 759 # =for reference
 760 # notes: *-files/-directories keys cannot have spaces, they're always
 761 # pika-escaped.  Everything after the first newline
 762 # A log entry looks like:
 763 # Revision: moodle-org--moodle--1.3.3--patch-15
 764 # Archive: arch-eduforge@catalyst.net.nz--2004
 765 # Creator: Penny Leach <penny@catalyst.net.nz>
 766 # Date: Wed May 25 14:15:34 NZST 2005
 767 # Standard-date: 2005-05-25 02:15:34 GMT
 768 # New-files: lang/de/.arch-ids/block_glossary_random.php.id
 769 #     lang/de/.arch-ids/block_html.php.id
 770 # New-directories: lang/de/help/questionnaire
 771 #     lang/de/help/questionnaire/.arch-ids
 772 # Renamed-files: .arch-ids/db_sears.sql.id db/.arch-ids/db_sears.sql.id
 773 #    db_sears.sql db/db_sears.sql
 774 # Removed-files: lang/be/docs/.arch-ids/release.html.id
 775 #     lang/be/docs/.arch-ids/releaseold.html.id
 776 # Modified-files: admin/cron.php admin/delete.php
 777 #     admin/editor.html backup/lib.php backup/restore.php
 778 # New-patches: arch-eduforge@catalyst.net.nz--2004/moodle-org--moodle--1.3.3--patch-15
 779 # Summary: Updating to latest from MOODLE_14_STABLE (1.4.5+)
 780 #   summary can be multiline with a leading space just like the above fields
 781 # Keywords:
 782 #
 783 # Updating yadda tadda tadda madda
 784 sub parselog {
 785     my ($ps, $log) = @_;
 786     my $key = undef;
 787
 788     # headers we want that contain filenames:
 789     my %want_headers = (
 790         new_files => 1,
 791         modified_files => 1,
 792         renamed_files => 1,
 793         renamed_directories => 1,
 794         removed_files => 1,
 795         removed_directories => 1,
 796     );
 797
 798     chomp (@$log);
 799     while ($_ = shift @$log) {
 800         if (/^Continuation-of:\s*(.*)/) {
 801             $ps->{tag} = $1;
 802             $key = undef;
 803         } elsif (/^Summary:\s*(.*)$/ ) {
 804             # summary can be multiline as long as it has a leading space.
 805             # we squeeze it onto a single line, though.
 806             $ps->{summary} = [ $1 ];
 807             $key = 'summary';
 808         } elsif (/^Creator: (.*)\s*<([^\>]+)>/) {
 809             $ps->{author} = $1;
 810             $ps->{email} = $2;
 811             $key = undef;
 812         # any *-files or *-directories can be read here:
 813         } elsif (/^([A-Z][a-z\-]+):\s*(.*)$/) {
 814             my $val = $2;
 815             $key = lc $1;
 816             $key =~ tr/-/_/; # too lazy to quote :P
 817             if ($want_headers{$key}) {
 818                 push @{$ps->{$key}}, split(/\s+/, $val);
 819             } else {
 820                 $key = undef;
 821             }
 822         } elsif (/^$/) {
 823             last; # remainder of @$log that didn't get shifted off is message
 824         } elsif ($key) {
 825             if (/^\s+(.*)$/) {
 826                 if ($key eq 'summary') {
 827                     push @{$ps->{$key}}, $1;
 828                 } else { # files/directories:
 829                     push @{$ps->{$key}}, split(/\s+/, $1);
 830                 }
 831             } else {
 832                 $key = undef;
 833             }
 834         }
 835     }
 836
 837     # drop leading empty lines from the log message
 838     while (@$log && $log->[0] eq '') {
 839         shift @$log;
 840     }
 841     if (exists $ps->{summary} && @{$ps->{summary}}) {
 842         $ps->{summary} = join(' ', @{$ps->{summary}});
 843     }
 844     elsif (@$log == 0) {
 845         $ps->{summary} = 'empty commit message';
 846     } else {
 847         $ps->{summary} = $log->[0] . '...';
 848     }
 849     $ps->{message} = join("\n",@$log);
 850
 851     # skip Arch control files, unescape pika-escaped files
 852     foreach my $k (keys %want_headers) {
 853         next unless (defined $ps->{$k});
 854         my @tmp = ();
 855         foreach my $t (@{$ps->{$k}}) {
 856            next unless length ($t);
 857            next if $t =~ m!\{arch\}/!;
 858            next if $t =~ m!\.arch-ids/!;
 859            # should we skip this?
 860            next if $t =~ m!\.arch-inventory$!;
 861            # tla cat-archive-log will give us filenames with spaces as file\(sp)name - why?
 862            # we can assume that any filename with \ indicates some pika escaping that we want to get rid of.
 863            if ($t =~ /\\/ ){
 864                $t = (safe_pipe_capture($TLA,'escape','--unescaped',$t))[0];
 865            }
 866            push @tmp, $t;
 867         }
 868         $ps->{$k} = \@tmp;
 869     }
 870 }
 871
 872 # write/read a tag
 873 sub tag {
 874     my ($tag, $commit) = @_;
 875
 876     if ($opt_o) {
 877         $tag =~ s|/|--|g;
 878     } else {
 879         my $patchname = $tag;
 880         $patchname =~ s/.*--//;
 881         $tag = git_branchname ($tag) . '--' . $patchname;
 882     }
 883
 884     if ($commit) {
 885         open(C,">","$git_dir/refs/tags/$tag")
 886             or die "Cannot create tag $tag: $!\n";
 887         print C "$commit\n"
 888             or die "Cannot write tag $tag: $!\n";
 889         close(C)
 890             or die "Cannot write tag $tag: $!\n";
 891         print " * Created tag '$tag' on '$commit'\n" if $opt_v;
 892     } else {                    # read
 893         open(C,"<","$git_dir/refs/tags/$tag")
 894             or die "Cannot read tag $tag: $!\n";
 895         $commit = <C>;
 896         chomp $commit;
 897         die "Error reading tag $tag: $!\n" unless length $commit == 40;
 898         close(C)
 899             or die "Cannot read tag $tag: $!\n";
 900         return $commit;
 901     }
 902 }
 903
 904 # write/read a private tag
 905 # reads fail softly if the tag isn't there
 906 sub ptag {
 907     my ($tag, $commit) = @_;
 908
 909     # don't use subdirs for tags yet, it could screw up other porcelains
 910     $tag =~ s|/|,|g;
 911
 912     my $tag_file = "$ptag_dir/$tag";
 913     my $tag_branch_dir = dirname($tag_file);
 914     mkpath($tag_branch_dir) unless (-d $tag_branch_dir);
 915
 916     if ($commit) {              # write
 917         open(C,">",$tag_file)
 918             or die "Cannot create tag $tag: $!\n";
 919         print C "$commit\n"
 920             or die "Cannot write tag $tag: $!\n";
 921         close(C)
 922             or die "Cannot write tag $tag: $!\n";
 923         $rptags{$commit} = $tag
 924             unless $tag =~ m/--base-0$/;
 925     } else {                    # read
 926         # if the tag isn't there, return 0
 927         unless ( -s $tag_file) {
 928             return 0;
 929         }
 930         open(C,"<",$tag_file)
 931             or die "Cannot read tag $tag: $!\n";
 932         $commit = <C>;
 933         chomp $commit;
 934         die "Error reading tag $tag: $!\n" unless length $commit == 40;
 935         close(C)
 936             or die "Cannot read tag $tag: $!\n";
 937         unless (defined $rptags{$commit}) {
 938             $rptags{$commit} = $tag;
 939         }
 940         return $commit;
 941     }
 942 }
 943
 944 sub find_parents {
 945     #
 946     # Identify what branches are merging into me
 947     # and whether we are fully merged
 948     # git-merge-base <headsha> <headsha> should tell
 949     # me what the base of the merge should be
 950     #
 951     my $ps = shift;
 952
 953     my %branches; # holds an arrayref per branch
 954                   # the arrayref contains a list of
 955                   # merged patches between the base
 956                   # of the merge and the current head
 957
 958     my @parents;  # parents found for this commit
 959
 960     # simple loop to split the merges
 961     # per branch
 962     foreach my $merge (@{$ps->{merges}}) {
 963         my $branch = git_branchname($merge);
 964         unless (defined $branches{$branch} ){
 965             $branches{$branch} = [];
 966         }
 967         push @{$branches{$branch}}, $merge;
 968     }
 969
 970     #
 971     # foreach branch find a merge base and walk it to the
 972     # head where we are, collecting the merged patchsets that
 973     # Arch has recorded. Keep that in @have
 974     # Compare that with the commits on the other branch
 975     # between merge-base and the tip of the branch (@need)
 976     # and see if we have a series of consecutive patches
 977     # starting from the merge base. The tip of the series
 978     # of consecutive patches merged is our new parent for
 979     # that branch.
 980     #
 981     foreach my $branch (keys %branches) {
 982
 983         # check that we actually know about the branch
 984         next unless -e "$git_dir/refs/heads/$branch";
 985
 986         my $mergebase = `git-merge-base $branch $ps->{branch}`;
 987         if ($?) {
 988             # Don't die here, Arch supports one-way cherry-picking
 989             # between branches with no common base (or any relationship
 990             # at all beforehand)
 991             warn "Cannot find merge base for $branch and $ps->{branch}";
 992             next;
 993         }
 994         chomp $mergebase;
 995
 996         # now walk up to the mergepoint collecting what patches we have
 997         my $branchtip = git_rev_parse($ps->{branch});
 998         my @ancestors = `git-rev-list --topo-order $branchtip ^$mergebase`;
 999         my %have; # collected merges this branch has
1000         foreach my $merge (@{$ps->{merges}}) {
1001             $have{$merge} = 1;
1002         }
1003         my %ancestorshave;
1004         foreach my $par (@ancestors) {
1005             $par = commitid2pset($par);
1006             if (defined $par->{merges}) {
1007                 foreach my $merge (@{$par->{merges}}) {
1008                     $ancestorshave{$merge}=1;
1009                 }
1010             }
1011         }
1012         # print "++++ Merges in $ps->{id} are....\n";
1013         # my @have = sort keys %have;   print Dumper(\@have);
1014
1015         # merge what we have with what ancestors have
1016         %have = (%have, %ancestorshave);
1017
1018         # see what the remote branch has - these are the merges we
1019         # will want to have in a consecutive series from the mergebase
1020         my $otherbranchtip = git_rev_parse($branch);
1021         my @needraw = `git-rev-list --topo-order $otherbranchtip ^$mergebase`;
1022         my @need;
1023         foreach my $needps (@needraw) {         # get the psets
1024             $needps = commitid2pset($needps);
1025             # git-rev-list will also
1026             # list commits merged in via earlier
1027             # merges. we are only interested in commits
1028             # from the branch we're looking at
1029             if ($branch eq $needps->{branch}) {
1030                 push @need, $needps->{id};
1031             }
1032         }
1033
1034         # print "++++ Merges from $branch we want are....\n";
1035         # print Dumper(\@need);
1036
1037         my $newparent;
1038         while (my $needed_commit = pop @need) {
1039             if ($have{$needed_commit}) {
1040                 $newparent = $needed_commit;
1041             } else {
1042                 last; # break out of the while
1043             }
1044         }
1045         if ($newparent) {
1046             push @parents, $newparent;
1047         }
1048
1049
1050     } # end foreach branch
1051
1052     # prune redundant parents
1053     my %parents;
1054     foreach my $p (@parents) {
1055         $parents{$p} = 1;
1056     }
1057     foreach my $p (@parents) {
1058         next unless exists $psets{$p}{merges};
1059         next unless ref    $psets{$p}{merges};
1060         my @merges = @{$psets{$p}{merges}};
1061         foreach my $merge (@merges) {
1062             if ($parents{$merge}) {
1063                 delete $parents{$merge};
1064             }
1065         }
1066     }
1067
1068     @parents = ();
1069     foreach (keys %parents) {
1070         push @parents, '-p', ptag($_);
1071     }
1072     return @parents;
1073 }
1074
1075 sub git_rev_parse {
1076     my $name = shift;
1077     my $val  = `git-rev-parse $name`;
1078     die "Error: git-rev-parse $name" if $?;
1079     chomp $val;
1080     return $val;
1081 }
1082
1083 # resolve a SHA1 to a known patchset
1084 sub commitid2pset {
1085     my $commitid = shift;
1086     chomp $commitid;
1087     my $name = $rptags{$commitid}
1088         || die "Cannot find reverse tag mapping for $commitid";
1089     $name =~ s|,|/|;
1090     my $ps   = $psets{$name}
1091         || (print Dumper(sort keys %psets)) && die "Cannot find patchset for $name";
1092     return $ps;
1093 }
1094
1095
1096 # an alternative to `command` that allows input to be passed as an array
1097 # to work around shell problems with weird characters in arguments
1098 sub safe_pipe_capture {
1099     my @output;
1100     if (my $pid = open my $child, '-|') {
1101         @output = (<$child>);
1102         close $child or die join(' ',@_).": $! $?";
1103     } else {
1104         exec(@_) or die "$! $?"; # exec() can fail the executable can't be found
1105     }
1106     return wantarray ? @output : join('',@output);
1107 }
1108
1109 # `tla logs -rf -d <dir> | head -n1` or `baz tree-id <dir>`
1110 sub arch_tree_id {
1111     my $dir = shift;
1112     chomp( my $ret = (safe_pipe_capture($TLA,'logs','-rf','-d',$dir))[0] );
1113     return $ret;
1114 }
1115
1116 sub archive_reachable {
1117     my $archive = shift;
1118     return 1 if $reachable{$archive};
1119     return 0 if $unreachable{$archive};
1120
1121     if (system "$TLA whereis-archive $archive >/dev/null") {
1122         if ($opt_a && (system($TLA,'register-archive',
1123                       "http://mirrors.sourcecontrol.net/$archive") == 0)) {
1124             $reachable{$archive} = 1;
1125             return 1;
1126         }
1127         print STDERR "Archive is unreachable: $archive\n";
1128         $unreachable{$archive} = 1;
1129         return 0;
1130     } else {
1131         $reachable{$archive} = 1;
1132         return 1;
1133     }
1134 }