1 # Copyright (c) 2010-2012 Zmanda, Inc. All Rights Reserved.
3 # This program is free software; you can redistribute it and/or modify it
4 # under the terms of the GNU General Public License version 2 as published
5 # by the Free Software Foundation.
7 # This program is distributed in the hope that it will be useful, but
8 # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
9 # or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 # You should have received a copy of the GNU General Public License along
13 # with this program; if not, write to the Free Software Foundation, Inc.,
14 # 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 # Contact information: Zmanda Inc., 465 S. Mathilda Ave., Suite 300
17 # Sunnyvale, CA 94085, USA, or: http://www.zmanda.com
19 package Amanda::Recovery::Scan;
27 use base qw(Exporter);
28 our @EXPORT_OK = qw($DEFAULT_CHANGER);
32 use Amanda::Device qw( :constants );
33 use Amanda::Debug qw( debug );
36 use Amanda::Interactivity;
38 use constant SCAN_ASK => 1; # call Amanda::Interactivity module
39 use constant SCAN_POLL => 2; # wait 'poll_delay' and retry the scan.
40 use constant SCAN_FAIL => 3; # abort
41 use constant SCAN_CONTINUE => 4; # continue to the next step
42 use constant SCAN_ASK_POLL => 5; # call Amanda::Interactivity module and
43 # poll at the same time.
47 Amanda::Recovery::Scan -- interface to scan algorithm
51 use Amanda::Recovey::Scan;
53 # scan the default changer with no interactivity
54 my $scan = Amanda::Recovery::Scan->new();
55 # ..or scan the changer $chg, using $interactivity for interactivity
56 $scan = Amanda::Recovery::Scan->new(chg => $chg,
57 interactivity => $interactivity);
62 my ($err, $reservation) = @_;
66 $dev = $reservation->{device};
71 $reservation->release(finished_cb => $start_next_volume);
74 $scan->quit(); # also quit the changer
79 This package provides a way for programs that need to read data from volumes
80 (loosely called "recovery" programs) to find the volumes they need in a
81 configurable way. It takes care of prompting for volumes when they are not
82 available, juggling multiple changers, and any other unpredictabilities.
86 Like L<Amanda::Changer>, this package operates asynchronously, and thus
87 requires that the caller use L<Amanda::MainLoop> to poll for events.
89 A new Scan object is created with the C<new> function as follows:
91 my $scan = Amanda::Recovery::Scan->new(scan_conf => $scan_conf,
93 interactivity => $interactivity);
95 C<scan_conf> is the configuration for the scan, which at this point should be
96 omitted, as configuration is not yet supported. The C<chg> parameter specifies
97 the changer to start the scan with. The default changer is used if C<chg> is
98 omitted. The C<interactivity> parameter gives an C<Amanda::Interactivity> object.
102 Many of the callbacks used by this package are identical to the callbacks of
103 the same name in L<Amanda::Changer>.
105 When a callback is called with an error, it is an object of type
106 C<Amanda::Changer::Error>. The C<volinuse> reason has a different meaning: it
107 means that the volume with that label is present in the changer, but is in use
114 $scan->find_volume(label => $label,
116 user_msg_fn => $user_msg_fn,
119 Find the volume labelled C<$label> and call C<$res_cb>. C<$user_msg_fn> is
120 used to send progress information, The argumnet it takes are describe in
121 the next section. As with the C<load> method
122 of the changer API, C<set_current> should be set to 1 if you want the scan to
123 set the current slot.
129 The cleanly terminate a scan objet, the changer quit is also called.
133 The user_msg_fn take various arguments
135 Initiate the scan of the slot $slot:
136 $self->user_msg_fn(scan_slot => 1,
139 Initiate the scan of the slot $slot which should have the label $label:
140 $self->user_msg_fn(scan_slot => 1,
144 The result of scanning slot $slot:
145 $self->user_msg_fn(slot_result => 1,
150 Other options can be added at any time. The function can ignore them.
154 our $DEFAULT_CHANGER = {};
159 my $scan_conf = $params{'scan_conf'};
160 my $chg = $params{'chg'};
161 my $interactivity = $params{'interactivity'};
163 #until we have a config for it.
164 $scan_conf = Amanda::Recovery::Scan::Config->new();
165 $chg = Amanda::Changer->new() if !defined $chg;
166 return $chg if $chg->isa("Amanda::Changer::Error");
171 scan_conf => $scan_conf,
172 interactivity => $interactivity,
174 return bless ($self, $class);
180 die("Recovery::Scan detroyed without quit") if defined $self->{'scan_conf'};
186 $self->{'chg'}->quit() if defined $self->{'chg'};
188 foreach (keys %$self) {
198 my $label = $params{'label'};
199 my $user_msg_fn = $params{'user_msg_fn'} || \&_user_msg_fn;
206 my $scan_running = 0;
207 my $interactivity_running = 0;
208 my $restart_scan = 0;
209 my $abort_scan = undef;
210 my $last_err = undef; # keep the last meaningful error, the one reported
211 # to the user, most scan end with the notfound error,
212 # it's more interesting to report an error from the
215 my $remove_undef_state = 0;
216 my $load_for_label = 0; # 1 = Try to load the slot with the correct label
217 # 0 = Load a slot with an unknown label
219 my $steps = define_steps
220 cb_ref => \$params{'res_cb'};
222 step get_first_inventory => sub {
223 Amanda::Debug::debug("find_volume labeled '$label'");
226 $self->{'chg'}->inventory(inventory_cb => $steps->{'got_first_inventory'});
229 step got_first_inventory => sub {
230 (my $err, $inventory) = @_;
232 if ($err && $err->notimpl) {
233 #inventory not implemented
234 return $self->_find_volume_no_inventory(%params);
237 return $steps->{'call_res_cb'}->($err, undef);
240 # find current slot and keep a private copy of the value
241 for my $i (0..(scalar(@$inventory)-1)) {
242 if ($inventory->[$i]->{current}) {
243 $current = $inventory->[$i]->{slot};
248 if (!defined $current) {
249 if (scalar(@$inventory) == 0) {
252 $current = $inventory->[0]->{slot};
256 # continue parsing the inventory
257 $steps->{'parse_inventory'}->($err, $inventory);
260 step restart_scan => sub {
262 return $steps->{'get_inventory'}->();
265 step get_inventory => sub {
266 $self->{'chg'}->inventory(inventory_cb => $steps->{'parse_inventory'});
269 step parse_inventory => sub {
270 (my $err, $inventory) = @_;
272 if ($err && $err->notimpl) {
273 #inventory not implemented
274 return $self->_find_volume_no_inventory(%params);
276 return $steps->{'handle_error'}->($err, undef) if $err;
278 # throw out the inventory result and move on if the situation has
279 # changed while we were waiting
280 return $steps->{'abort_scan'}->() if $abort_scan;
281 return $steps->{'restart_scan'}->() if $restart_scan;
283 # check if label is in the inventory
284 for my $i (0..(scalar(@$inventory)-1)) {
285 my $sl = $inventory->[$i];
286 if (defined $sl->{'label'} and
287 $sl->{'label'} eq $label and
288 !defined $seen{$sl->{'slot'}}) {
289 $slot_scanned = $sl->{'slot'};
290 if ($sl->{'reserved'}) {
291 return $steps->{'handle_error'}->(
292 Amanda::Changer::Error->new('failed',
293 reason => 'volinuse',
294 message => "Volume '$label' in slot $slot_scanned is reserved"),
297 Amanda::Debug::debug("parse_inventory: load slot $slot_scanned with label '$label'");
298 $user_msg_fn->(scan_slot => 1,
299 slot => $slot_scanned,
301 $seen{$slot_scanned} = { device_status => $sl->{'device_status'},
302 f_type => $sl->{'f_type'},
303 label => $sl->{'label'} };
305 return $self->{'chg'}->load(slot => $slot_scanned,
306 res_cb => $steps->{'slot_loaded'},
307 set_current => $params{'set_current'});
311 # Remove from seen all slot that have state == SLOT_UNKNOWN
312 # It is done when as scan is restarted from interactivity object.
313 if ($remove_undef_state) {
314 for my $i (0..(scalar(@$inventory)-1)) {
315 my $slot = $inventory->[$i]->{slot};
316 if (exists($seen{$slot}) &&
317 !defined($inventory->[$i]->{state})) {
321 $remove_undef_state = 0;
324 # remove any slots where the state has changed from the list of seen slots
325 for my $i (0..(scalar(@$inventory)-1)) {
326 my $sl = $inventory->[$i];
327 my $slot = $sl->{slot};
329 defined($sl->{'state'}) &&
330 (($seen{$slot}->{'device_status'} != $sl->{'device_status'}) ||
331 (defined $seen{$slot}->{'device_status'} &&
332 $seen{$slot}->{'device_status'} == $DEVICE_STATUS_SUCCESS &&
333 $seen{$slot}->{'f_type'} != $sl->{'f_type'}) ||
334 (defined $seen{$slot}->{'device_status'} &&
335 $seen{$slot}->{'device_status'} == $DEVICE_STATUS_SUCCESS &&
336 defined $seen{$slot}->{'f_type'} &&
337 $seen{$slot}->{'f_type'} == $Amanda::Header::F_TAPESTART &&
338 $seen{$slot}->{'label'} ne $sl->{'label'}))) {
343 # scan any unseen slot already in a drive, if configured to do so
344 if ($self->{'scan_conf'}->{'scan_drive'}) {
345 for my $sl (@$inventory) {
346 my $slot = $sl->{'slot'};
347 if (defined $sl->{'loaded_in'} &&
348 !$sl->{'reserved'} &&
350 $slot_scanned = $slot;
351 $user_msg_fn->(scan_slot => 1, slot => $slot_scanned);
352 $seen{$slot_scanned} = { device_status => $sl->{'device_status'},
353 f_type => $sl->{'f_type'},
354 label => $sl->{'label'} };
356 return $self->{'chg'}->load(slot => $slot_scanned,
357 res_cb => $steps->{'slot_loaded'},
358 set_current => $params{'set_current'});
364 if ($self->{'scan_conf'}->{'scan_unknown_slot'}) {
365 #find index for current slot
366 my $current_index = undef;
367 for my $i (0..(scalar(@$inventory)-1)) {
368 my $slot = $inventory->[$i]->{slot};
369 if ($slot eq $current) {
374 #scan next slot to scan
375 $current_index = 0 if !defined $current_index;
376 for my $i ($current_index..(scalar(@$inventory)-1), 0..($current_index-1)) {
377 my $sl = $inventory->[$i];
378 my $slot = $sl->{slot};
379 # skip slots we've seen
380 next if defined($seen{$slot});
381 # skip slots that are empty
382 next if defined $sl->{'state'} &&
383 $sl->{'state'} == Amanda::Changer::SLOT_EMPTY;
384 # skip slots for which we have a known label, since it's not the
386 next if defined $sl->{'f_type'} &&
387 $sl->{'f_type'} == $Amanda::Header::F_TAPESTART;
388 next if defined $sl->{'label'};
390 # found a slot to check - reset our current slot
392 $slot_scanned = $current;
393 Amanda::Debug::debug("parse_inventory: load slot $current");
394 $user_msg_fn->(scan_slot => 1, slot => $slot_scanned);
395 $seen{$slot_scanned} = { device_status => $sl->{'device_status'},
396 f_type => $sl->{'f_type'},
397 label => $sl->{'label'} };
399 return $self->{'chg'}->load(slot => $slot_scanned,
400 res_cb => $steps->{'slot_loaded'},
401 set_current => $params{'set_current'});
405 #All slots are seen or empty.
407 return $steps->{'handle_error'}->($last_err, undef);
409 return $steps->{'handle_error'}->(
410 Amanda::Changer::Error->new('failed',
411 reason => 'notfound',
412 message => "Volume '$label' not found"),
417 step slot_loaded => sub {
418 (my $err, $res) = @_;
420 # we don't responsd to abort_scan or restart_scan here, since we
421 # have an open reservation that we should deal with.
423 $user_msg_fn->(slot_result => 1,
424 slot => $slot_scanned,
428 if ($res->{device}->status == $DEVICE_STATUS_SUCCESS &&
429 $res->{device}->volume_label &&
430 $res->{device}->volume_label eq $label) {
431 my $volume_label = $res->{device}->volume_label;
432 return $steps->{'call_res_cb'}->(undef, $res);
435 if (defined $res->{device}->volume_header) {
436 $f_type = $res->{device}->volume_header->{type};
441 # The slot did not contain the volume we wanted, so mark it
442 # as seen and try again.
443 $seen{$slot_scanned} = {
444 device_status => $res->{device}->status,
446 label => $res->{device}->volume_label
450 if ($res->{device}->status == $DEVICE_STATUS_SUCCESS) {
453 $last_err = Amanda::Changer::Error->new('fatal',
454 message => $res->{device}->error_or_status());
456 return $res->release(finished_cb => $steps->{'load_released'});
458 if ($load_for_label == 0 && $err->volinuse) {
459 # Scan semantics for volinuse is different than changer.
460 # If a slot with unknown label is loaded then we map
461 # volinuse to driveinuse.
462 $err->{reason} = "driveinuse";
464 $last_err = $err if $err->fatal || !$err->notfound;
465 if ($load_for_label == 1 && $err->failed && $err->volinuse) {
466 # volinuse is an error
467 return $steps->{'handle_error'}->($err, $steps->{'load_released'});
469 return $steps->{'load_released'}->();
473 step load_released => sub {
480 # throw out the inventory result and move on if the situation has
481 # changed while we were loading a volume
482 return $steps->{'abort_scan'}->() if $abort_scan;
483 return $steps->{'restart_scan'}->() if $restart_scan;
485 $new_slot = $current;
486 $steps->{'get_inventory'}->();
489 step handle_error => sub {
490 my ($err, $continue_cb) = @_;
492 my $scan_method = undef;
497 $poll_src->remove() if defined $poll_src;
500 # prefer to use scan method for $last_err, if present
501 if ($last_err && $err->failed && $err->notfound) {
502 $message = "$last_err";
504 if ($last_err->isa("Amanda::Changer::Error")) {
505 if ($last_err->fatal) {
506 $scan_method = $self->{'scan_conf'}->{'fatal'};
508 $scan_method = $self->{'scan_conf'}->{$last_err->{'reason'}};
510 } elsif ($continue_cb) {
511 $scan_method = SCAN_CONTINUE;
515 #use scan method for $err
516 if (!defined $scan_method) {
518 $message = "$err" if !defined $message;
520 $scan_method = $self->{'scan_conf'}->{'fatal'};
522 $scan_method = $self->{'scan_conf'}->{$err->{'reason'}};
525 confess("error not defined");
526 $scan_method = SCAN_ASK_POLL;
530 ## implement the desired scan method
532 if ($scan_method == SCAN_CONTINUE && !defined $continue_cb) {
533 $scan_method = $self->{'scan_conf'}->{'notfound'};
534 if ($scan_method == SCAN_CONTINUE) {
535 $scan_method = SCAN_FAIL;
539 if ($scan_method == SCAN_ASK && !defined $self->{'interactivity'}) {
540 $scan_method = SCAN_FAIL;
543 if ($scan_method == SCAN_ASK_POLL && !defined $self->{'interactivity'}) {
544 $scan_method = SCAN_FAIL;
547 if ($scan_method == SCAN_ASK) {
548 return $steps->{'scan_interactivity'}->("$message");
549 } elsif ($scan_method == SCAN_POLL) {
550 $poll_src = Amanda::MainLoop::call_after(
551 $self->{'scan_conf'}->{'poll_delay'},
552 $steps->{'after_poll'});
554 } elsif ($scan_method == SCAN_ASK_POLL) {
555 $steps->{'scan_interactivity'}->("$message\n");
556 $poll_src = Amanda::MainLoop::call_after(
557 $self->{'scan_conf'}->{'poll_delay'},
558 $steps->{'after_poll'});
560 } elsif ($scan_method == SCAN_FAIL) {
561 return $steps->{'call_res_cb'}->($err, undef);
562 } elsif ($scan_method == SCAN_CONTINUE) {
563 return $continue_cb->($err, undef);
565 confess("Invalid SCAN_* value:$err:$err->{'reason'}:$scan_method");
569 step after_poll => sub {
570 $poll_src->remove() if defined $poll_src;
572 return $steps->{'restart_scan'}->();
575 step scan_interactivity => sub {
576 my ($err_message) = @_;
577 if (!$interactivity_running) {
578 $interactivity_running = 1;
579 my $message = "$err_message\nInsert volume labeled '$label' in changer and type <enter>\nor type \"^D\" to abort\n";
580 $self->{'interactivity'}->user_request(
583 err => "$err_message",
584 chg_name => $self->{'chg'}->{'chg_name'},
585 request_cb => $steps->{'scan_interactivity_cb'});
590 step scan_interactivity_cb => sub {
591 my ($err, $message) = @_;
592 $interactivity_running = 0;
593 $poll_src->remove() if defined $poll_src;
601 return $steps->{'call_res_cb'}->($err, undef);
605 if ($message ne '') {
608 if (ref($message) eq 'HASH' and $message == $DEFAULT_CHANGER) {
609 $new_chg = Amanda::Changer->new();
611 $new_chg = Amanda::Changer->new($message);
613 if ($new_chg->isa("Amanda::Changer::Error")) {
614 return $steps->{'scan_interactivity'}->("$new_chg");
617 $self->{'chg'}->quit();
618 $self->{'chg'} = $new_chg;
621 $remove_undef_state = 1;
628 return $steps->{'restart_scan'}->();
632 step abort_scan => sub {
633 $steps->{'call_res_cb'}->($abort_scan, undef);
636 step call_res_cb => sub {
637 (my $err, $res) = @_;
639 # TODO: what happens if the search was aborted or
640 # restarted in the interim?
643 $poll_src->remove() if defined $poll_src;
645 $interactivity_running = 0;
646 $self->{'interactivity'}->abort() if defined $self->{'interactivity'};
647 $params{'res_cb'}->($err, $res);
652 sub _find_volume_no_inventory {
656 my $label = $params{'label'};
664 my $steps = define_steps
665 cb_ref => \$params{'res_cb'};
667 step load_label => sub {
668 return $self->{'chg'}->load(relative_slot => "current",
669 res_cb => $steps->{'load_label_cb'});
672 step load_label_cb => sub {
673 (my $err, $res) = @_;
676 if ($err->failed && $err->notfound) {
677 if ($err->{'message'} eq "all slots have been loaded") {
678 $err->{'message'} = "label '$label' not found";
680 return $params{'res_cb'}->($err, undef);
681 } elsif ($err->failed && $err->volinuse and defined $err->{'slot'}) {
682 $last_slot = $err->{'slot'};
684 #no interactivity yet.
685 return $params{'res_cb'}->($err, undef);
688 $last_slot = $res->{'this_slot'}
691 $seen_slots{$last_slot} = 1 if defined $last_slot;
693 my $dev = $res->{'device'};
694 if (defined $dev->volume_label && $dev->volume_label eq $label) {
695 return $params{'res_cb'}->(undef, $res);
697 return $res->release(finished_cb => $steps->{'released'});
699 return $steps->{'released'}->()
703 step released => sub {
704 $self->{'chg'}->load(relative_slot => "next",
705 except_slots => \%seen_slots,
706 res_cb => $steps->{'load_label_cb'},
715 package Amanda::Recovery::Scan::Config;
721 my $self = bless {}, $class;
723 $self->{'scan_drive'} = 0;
724 $self->{'scan_unknown_slot'} = 1;
725 $self->{'poll_delay'} = 10000; #10 seconds
727 $self->{'fatal'} = Amanda::Recovery::Scan::SCAN_CONTINUE;
728 $self->{'driveinuse'} = Amanda::Recovery::Scan::SCAN_ASK_POLL;
729 $self->{'volinuse'} = Amanda::Recovery::Scan::SCAN_ASK_POLL;
730 $self->{'notfound'} = Amanda::Recovery::Scan::SCAN_ASK_POLL;
731 $self->{'unknown'} = Amanda::Recovery::Scan::SCAN_FAIL;
732 $self->{'notimpl'} = Amanda::Recovery::Scan::SCAN_FAIL;
733 $self->{'invalid'} = Amanda::Recovery::Scan::SCAN_CONTINUE;