This file is indexed.

/usr/share/hplip/base/module.py is in hplip-data 3.16.3+repack0-1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
# -*- coding: utf-8 -*-
#
# (c) Copyright 2003-2015 HP Development Company, L.P.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
#
# Author: Don Welch
#

# Std Lib
import sys
import re
import getopt
import os

# Local
from .g import *
from . import tui, utils, device

USAGE_FLAG_NONE = 0x00
USAGE_FLAG_DEVICE_ARGS = 0x01
USAGE_FLAG_SUPRESS_G_DEBUG_FLAG = 0x02
USAGE_FLAG_FILE_ARGS = 0x04



class Module(object):
    def __init__(self, mod, title, version, doc,
                 usage_data=None, avail_modes=None,
                 supported_ui_toolkits=None,
                 run_as_root_ok=False, quiet=False, deprecated=False):

        self.mod = mod
        self.title = title
        self.version = version
        self.doc = doc
        self.usage_data = usage_data
        os.umask(0o037)
        log.set_module(mod)
        self.args = []
        self.quiet = quiet
        self.deprecated = deprecated
        self.lock_file = None
        self.help_only_support = False
        prop.prog = sys.argv[0]

        if os.getenv("HPLIP_DEBUG"):
            log.set_level('debug')

        self.avail_modes = avail_modes
        if supported_ui_toolkits is not None:
            self.supported_ui_toolkits = supported_ui_toolkits
            self.num_supported_ui_toolkits = len(self.supported_ui_toolkits)
        else:
            self.supported_ui_toolkits = []
            self.num_supported_ui_toolkits = 0

        self.default_ui_toolkit = sys_conf.get('configure', 'ui-toolkit', 'qt4')

        self.num_installed_ui_toolkits = 0
        self.installed_ui_toolkits = []
        if utils.to_bool(sys_conf.get('configure', 'qt3', '0')):
            self.installed_ui_toolkits.append(UI_TOOLKIT_QT3)
            self.num_installed_ui_toolkits += 1

        if utils.to_bool(sys_conf.get('configure', 'qt4', '0')):
            self.installed_ui_toolkits.append(UI_TOOLKIT_QT4)
            self.num_installed_ui_toolkits += 1

        self.default_mode = INTERACTIVE_MODE

        self.num_valid_modes = 0
        if self.avail_modes is not None:
            if GUI_MODE in self.avail_modes and prop.gui_build and self.installed_ui_toolkits:
                self.num_valid_modes += 1

            if INTERACTIVE_MODE in self.avail_modes:
                self.num_valid_modes += 1

            if NON_INTERACTIVE_MODE in self.avail_modes:
                self.num_valid_modes += 1

        if self.avail_modes is not None:
            if INTERACTIVE_MODE in self.avail_modes:
                self.default_mode = INTERACTIVE_MODE

            elif NON_INTERACTIVE_MODE in self.avail_modes:
                self.default_mode = NON_INTERACTIVE_MODE

        if self.supported_ui_toolkits is not None and prop.gui_build and self.installed_ui_toolkits:

            if self.default_ui_toolkit == 'qt3' and UI_TOOLKIT_QT4 in self.supported_ui_toolkits and \
                UI_TOOLKIT_QT3 not in self.supported_ui_toolkits and INTERACTIVE_MODE in self.avail_modes:

                # interactive + qt4 and default is qt3 --> set to interactive (if avail) (e.g., hp-align)
                self.default_mode = INTERACTIVE_MODE
                self.default_ui_toolkit = 'none'

            elif (UI_TOOLKIT_QT4 in self.supported_ui_toolkits and self.default_ui_toolkit == 'qt4' and UI_TOOLKIT_QT4 in self.installed_ui_toolkits) or \
                 (UI_TOOLKIT_QT3 in self.supported_ui_toolkits and self.default_ui_toolkit == 'qt3' and UI_TOOLKIT_QT3 in self.installed_ui_toolkits):

                self.default_mode = GUI_MODE

            elif self.default_ui_toolkit == 'qt3' and UI_TOOLKIT_QT3 not in self.supported_ui_toolkits:

                if UI_TOOLKIT_QT4 in self.supported_ui_toolkits and UI_TOOLKIT_QT4 in self.installed_ui_toolkits: # (e.g, hp-linefeedcal?)
                    self.default_ui_toolkit = 'qt4'
                    self.default_mode = GUI_MODE

                elif INTERACTIVE_MODE in self.avail_modes:
                    self.default_mode = INTERACTIVE_MODE

                elif NON_INTERACTIVE_MODE in self.avail_modes:
                    self.default_mode = NON_INTERACTIVE_MODE

                else:
                    log.error("%s cannot be run using Qt3 toolkit." % self.mod)
#                    sys.exit(1)
                    self.help_only_support = True

            elif self.default_ui_toolkit == 'qt4' and UI_TOOLKIT_QT4 not in self.supported_ui_toolkits:

                if UI_TOOLKIT_QT3 in self.supported_ui_toolkits and UI_TOOLKIT_QT3 in self.installed_ui_toolkits: # (e.g., hp-unload)
                    self.default_ui_toolkit = 'qt3'
                    self.default_mode = GUI_MODE

                elif INTERACTIVE_MODE in self.avail_modes:
                    self.default_mode = INTERACTIVE_MODE

                elif NON_INTERACTIVE_MODE in self.avail_modes:
                    self.default_mode = NON_INTERACTIVE_MODE

                else:
                    log.error("%s cannot be run using Qt4 toolkit." % self.mod)
#                    sys.exit(1)
                    self.help_only_support = True


        self.mode = self.default_mode

        #log.debug("Default ui-toolkit: %s" % self.default_ui_toolkit)
        #log.debug("Default mode: %s" % self.default_mode)

        if os.getuid() == 0 and not run_as_root_ok:
            log.warn("%s should not be run as root/superuser." % mod)


    def setUsage(self, include_flags=0, extra_options=None,
                 extra_notes=None, see_also_list=None):

        if self.doc:
            self.usage_data = [(self.doc, "", "name", True)]
        else:
            self.usage_data = []

        summary = ['Usage:', self.mod]
        content = []
        notes = []

        if include_flags & USAGE_FLAG_DEVICE_ARGS == USAGE_FLAG_DEVICE_ARGS:
            summary.append('[DEVICE_URI|PRINTER_NAME]')
            content.append(utils.USAGE_ARGS)
            content.append(utils.USAGE_DEVICE)
            content.append(utils.USAGE_PRINTER)

        if self.avail_modes is not None and self.num_valid_modes > 0:
            summary.append('[MODE]')
            content.append(utils.USAGE_SPACE)
            content.append(utils.USAGE_MODE)

            if self.num_installed_ui_toolkits > 0:
                if GUI_MODE in self.avail_modes and prop.gui_build:
                    content.append(utils.USAGE_GUI_MODE)

            if INTERACTIVE_MODE in self.avail_modes:
                content.append(utils.USAGE_INTERACTIVE_MODE)

            if NON_INTERACTIVE_MODE in self.avail_modes:
                content.append(utils.USAGE_NON_INTERACTIVE_MODE)

        # [options]
        summary.append('[OPTIONS]')
        content.append(utils.USAGE_SPACE)
        content.append(utils.USAGE_OPTIONS)

        if self.avail_modes is not None and GUI_MODE in self.avail_modes and \
            self.supported_ui_toolkits is not None and self.num_supported_ui_toolkits > 0 and \
            prop.gui_build and self.num_installed_ui_toolkits > 0:

            if UI_TOOLKIT_QT3 in self.supported_ui_toolkits and UI_TOOLKIT_QT3 in self.installed_ui_toolkits:
                content.append(utils.USAGE_USE_QT3)

            if UI_TOOLKIT_QT4 in self.supported_ui_toolkits and UI_TOOLKIT_QT4 in self.installed_ui_toolkits:
                content.append(utils.USAGE_USE_QT4)

        content.append(utils.USAGE_LOGGING1)
        content.append(utils.USAGE_LOGGING2)
        if include_flags & USAGE_FLAG_SUPRESS_G_DEBUG_FLAG != USAGE_FLAG_SUPRESS_G_DEBUG_FLAG:
            content.append(utils.USAGE_LOGGING3) # Issue with --gg in hp-sendfax

        # --loc/--lang
        #if self.avail_modes is not None and GUI_MODE in self.avail_modes and prop.gui_build:
        #    content.append(utils.USAGE_LANGUAGE)

        content.append(utils.USAGE_HELP)

        if extra_options is not None:
            for e in extra_options:
                content.append(e)

        # [FILES]
        if include_flags & USAGE_FLAG_FILE_ARGS:
            summary.append('[FILES]')

        # Notes
        if extra_notes is not None or notes:
            content.append(utils.USAGE_SPACE)
            content.append(utils.USAGE_NOTES)

            for n in notes:
                content.append(n)

            if extra_notes is not None:
                for n in extra_notes:
                    content.append(n)

        # See Also
        if see_also_list is not None:
            content.append(utils.USAGE_SPACE)
            content.append(utils.USAGE_SEEALSO)
            for s in see_also_list:
                content.append((s, '', 'seealso', False))

        content.insert(0, (' '.join(summary), '', 'summary', True))

        for c in content:
            self.usage_data.append(c)


    def parseStdOpts(self, extra_params=None,
                     extra_long_params=None,
                     handle_device_printer=True,
                     supress_g_debug_flag=False):

        params = 'l:h' # 'l:hq:'
        if not supress_g_debug_flag:
            params = ''.join([params, 'g'])

        long_params = ['logging=', 'help', 'help-rest', 'help-man',
                       'help-desc',
                       #'lang=', 'loc=',
                       'debug', 'dbg']

        if handle_device_printer:
            params = ''.join([params, 'd:p:P:'])
            long_params.extend(['device=', 'device-uri=', 'printer=', 'printer-name'])

        if self.num_valid_modes > 0:
            if GUI_MODE in self.avail_modes and prop.gui_build:
                params = ''.join([params, 'u'])
                long_params.extend(['gui', 'ui'])

            if INTERACTIVE_MODE in self.avail_modes:
                params = ''.join([params, 'i'])
                long_params.extend(['interactive', 'text'])

            if NON_INTERACTIVE_MODE in self.avail_modes:
                params = ''.join([params, 'n'])
                long_params.extend(['noninteractive', 'non-interactive', 'batch'])

        if self.supported_ui_toolkits is not None and \
            self.num_supported_ui_toolkits >= 1 and prop.gui_build and \
            self.avail_modes is not None and GUI_MODE in self.avail_modes:

            if UI_TOOLKIT_QT3 in self.supported_ui_toolkits and UI_TOOLKIT_QT3 in self.installed_ui_toolkits:
                long_params.extend(['qt3', 'use-qt3'])

            if UI_TOOLKIT_QT4 in self.supported_ui_toolkits and UI_TOOLKIT_QT4 in self.installed_ui_toolkits:
                long_params.extend(['qt4', 'use-qt4'])

        if extra_params is not None:
            params = ''.join([params, extra_params])

        if extra_long_params is not None:
            long_params.extend(extra_long_params)

        opts = None
        show_usage = None
        device_uri = None
        printer_name = None
        error_msg = []
        mode = self.default_mode
        if prop.gui_build:
            ui_toolkit = self.default_ui_toolkit
        else:
            ui_toolkit = 'none'
        lang = None

        try:
            opts, self.args = getopt.getopt(sys.argv[1:], params, long_params)
        except getopt.GetoptError as e:
            error_msg = [e.msg]

        else:
            for o, a in opts:
                if o in ('-d', '--device', '--device-uri'):
                    device_uri = a

                elif o in ('-P', '-p', '--printer', '--printer-name'):
                    printer_name = a

                elif o in ('-l', '--logging'):
                    log_level = a.lower().strip()
                    if not log.set_level(log_level):
                        show_usage = 'text'

                elif o in ('-g', '--debug', '--dbg'):
                    log.set_level('debug')

                elif o in ('-u', '--gui', '--ui'):
                    if self.avail_modes is not None and GUI_MODE in self.avail_modes and \
                        self.supported_ui_toolkits is not None and prop.gui_build:
                        mode = GUI_MODE
                    else:
                        error_msg.append("Unable to enter GUI mode.")

                elif o in ('-i', '--interactive', '--text'):
                    if self.avail_modes is not None and INTERACTIVE_MODE in self.avail_modes:
                        mode = INTERACTIVE_MODE
                        ui_toolkit = 'none'

                elif o in ('-n', '--non-interactive', '--batch'):
                    if self.avail_modes is not None and NON_INTERACTIVE_MODE in self.avail_modes:
                        mode = NON_INTERACTIVE_MODE
                        ui_toolkit = 'none'

                elif o in ('-h', '--help'):
                    show_usage = 'text'

                elif o == '--help-rest':
                    show_usage = 'rest'

                elif o == '--help-man':
                    show_usage = 'man'

                elif o == '--help-desc':
                    show_usage = 'desc'

                elif o in ('--qt3', '--use-qt3'):
                    if self.avail_modes is not None and GUI_MODE in self.avail_modes:
                        if self.supported_ui_toolkits is not None and \
                            UI_TOOLKIT_QT3 in self.supported_ui_toolkits and prop.gui_build and \
                            UI_TOOLKIT_QT3 in self.installed_ui_toolkits:

                            mode = GUI_MODE
                            ui_toolkit = 'qt3'
                        else:
                            error_msg.append("%s does not support Qt3. Unable to enter GUI mode." % self.mod)

                elif o in ('--qt4', '--use-qt4'):
                    if self.avail_modes is not None and GUI_MODE in self.avail_modes:
                        if self.supported_ui_toolkits is not None and \
                            UI_TOOLKIT_QT4 in self.supported_ui_toolkits and prop.gui_build and \
                            UI_TOOLKIT_QT4 in self.installed_ui_toolkits:

                            mode = GUI_MODE
                            ui_toolkit = 'qt4'
                        else:
                            error_msg.append("%s does not support Qt4. Unable to enter GUI mode." % self.mod)

                #elif o in ('--lang', '--loc'):
                #    if a.strip() == '?':
                #        utils.log_title(self.title, self.version)
                #        self.showLanguages()
                #        sys.exit(0)
                #    else:
                #        lang = utils.validate_language(a.lower())

        if error_msg:
            show_usage = 'text'

        if self.help_only_support:
            if show_usage or error_msg:
                self.usage(show_usage, error_msg)
            else:
                log.info(log.bold("\nPlease check usage '%s --help'"%self.mod))
                show_usage = 'text'
        else:
            self.usage(show_usage, error_msg)

        if show_usage is not None:
            sys.exit(0)

        self.mode = mode
        return opts, device_uri, printer_name, mode, ui_toolkit, lang


    def showLanguages(self):
        f = tui.Formatter()
        f.header = ("Language Code", "Alternate Name(s)")
        for loc, ll in list(supported_locales.items()):
            f.add((ll[0], ', '.join(ll[1:])))

        f.output()


    def usage(self, show_usage='text', error_msg=None):
        if show_usage is None:
            if not self.quiet:
                self.showTitle()
            return

        if show_usage == 'text':
            self.showTitle()
            log.info()

        if show_usage == 'desc':
            print(self.doc)

        else:
            utils.format_text(self.usage_data, show_usage, self.title, self.mod, self.version)

            if error_msg:
                for e in error_msg:
                    log.error(e)

                sys.exit(1)

            sys.exit(0)

            if show_usage == 'text':
                sys.exit(0)


    def showTitle(self, show_ver=True):
        if not self.quiet:
            log.info("")

            if show_ver:
                log.info(log.bold("HP Linux Imaging and Printing System (ver. %s)" % prop.version))
            else:
                log.info(log.bold("HP Linux Imaging and Printing System"))

            log.info(log.bold("%s ver. %s" % (self.title, self.version)))
            log.info("")
            log.info("Copyright (c) 2001-15 HP Development Company, LP")
            log.info("This software comes with ABSOLUTELY NO WARRANTY.")
            log.info("This is free software, and you are welcome to distribute it")
            log.info("under certain conditions. See COPYING file for more details.")
            log.info("")
            if self.deprecated:
                log.warn(log.bold("%s support is deprecated. Feature can be used as is. Fixes or updates will not be provided" %self.title))
                log.info("")


    def getDeviceUri(self, device_uri=None, printer_name=None, back_end_filter=device.DEFAULT_BE_FILTER,
                     filter=device.DEFAULT_FILTER, devices=None, restrict_to_installed_devices=True):
        """ Validate passed in parameters, and, if in text mode, have user select desired device to use.
            Used for tools that are device-centric and accept -d (and maybe also -p).
            Use the filter(s) to restrict what constitute valid devices.

            Return the matching device URI based on:
            1. Passed in device_uri if it is valid (filter passes)
            2. Corresponding device_uri from the printer_name if it is valid (filter passes) ('*' means default printer)
            3. User input from menu (based on bus and filter)

            device_uri and printer_name can both be specified if they correspond to the same device.

            Returns:
                device_uri|None
                (returns None if passed in device_uri is invalid or printer_name doesn't correspond to device_uri)
        """

        log.debug("getDeviceUri(%s, %s, %s, %s, , %s)" %
            (device_uri, printer_name, back_end_filter, filter, restrict_to_installed_devices))
        log.debug("Mode=%s" % self.mode)

        scan_uri_flag = False
        if 'hpaio' in back_end_filter:
            scan_uri_flag = True

        device_uri_ok = False
        printer_name_ok = False
        device_uri_ret = None

        if devices is None:
            devices = device.getSupportedCUPSDevices(back_end_filter, filter)
            log.debug(devices)
            if not devices and restrict_to_installed_devices:
                log.error("No device found that support this feature.")
                return None

        if device_uri is not None:
            if device_uri in devices:
                device_uri_ok = True

            elif restrict_to_installed_devices:
                log.error("'%s' device doesn't support this feature (or) Invalid device URI" % device_uri)
                return None

            else:
                device_uri_ok = True

        if printer_name is not None:
            #Find the printer_name in the models of devices
            log.debug(devices)
            for uri in devices:
               log.debug(uri)
               back_end, is_hp, bb, model, serial, dev_file, host, zc, port = \
                            device.parseDeviceURI(uri)
               log.debug("back_end=%s, is_hp=%s, bb=%s, model=%s, serial=%s, dev_file=%s, host=%s, zc=%s, port= %s" % (back_end, is_hp, bb, model, serial, dev_file, host, zc, port))
               cups_printer = devices[uri]
               if printer_name.lower() in [m.lower() for m in cups_printer]:
                   printer_name_ok = True 
                   printer_name_device_uri = device_uri = uri
                   device_uri_ok = True
            if printer_name_ok is not True: 
               log.error("'%s' device doesn't support this feature (or) Invalid printer name" % printer_name)
               printer_name = None
               if restrict_to_installed_devices:
                    return None



        if device_uri is not None and printer_name is None and device_uri_ok: # Only device_uri specified
            device_uri_ret = device_uri

        elif device_uri is not None and printer_name is not None: # Both specified
            if device_uri_ok and printer_name_ok:
                if device_uri == printer_name_device_uri:
                    device_uri_ret = device_uri
                else:
                    log.error("Printer name %s and device URI %s refer to different devices." % (printer_name, device_uri))
                    printer_name, printer_name = None, None

        elif device_uri is None and printer_name is not None and printer_name_ok: # Only printer name specified
            device_uri_ret = device.getDeviceURIByPrinterName(printer_name, scan_uri_flag)

        elif len(devices) == 1: # Nothing specified, and only 1 device avail.
            device_uri_ret = list(devices.keys())[0]

        if device_uri_ret is None and len(devices):
            if self.mode == INTERACTIVE_MODE:
                device_uri_ret = tui.device_table(devices, scan_uri_flag)
            else:
                device_uri_ret = list(devices.keys())[0]

        if device_uri_ret is not None:
            user_conf.set('last_used', 'device_uri', device_uri_ret)

        else:
            if self.mode in (INTERACTIVE_MODE, NON_INTERACTIVE_MODE):
                log.error("No device selected/specified or that supports this functionality.")
                sys.exit(1)
#            else:
#                log.debug("No device selected/specified")

        return device_uri_ret


    def getPrinterName(self, printer_name, device_uri, back_end_filter=device.DEFAULT_BE_FILTER,
                       filter=device.DEFAULT_FILTER, restrict_to_installed_devices=True):
        """ Validate passed in parameters, and, if in text mode, have user select desired printer to use.
            Used for tools that are printer queue-centric and accept -p (and maybe also -d).
            Use the filter(s) to restrict what constitute valid printers.

            Return the matching printer_name based on:
            1. Passed in printer_name if it is valid (filter passes) ('*' means default printer)
            2. From single printer_name of corresponding passed in device_uri (filter passes)
            3. User input from menu (CUPS printer list, filtered) [or if > 1 queue for device_uri]

            device_uri and printer_name can both be specified if they correspond to the same device.

            Returns:
                (printer_name|None, device_uri|None) (tuple)
                (returns None if passed in printer_name is invalid or device_uri doesn't correspond to printer_name)
        """

        log.debug("getPrinterName(%s, %s, %s, %s)" % (device_uri, printer_name, back_end_filter, filter))
        log.debug("Mode=%s" % self.mode)

        device_uri_ok = False
        printer_name_ok = False
        printer_name_ret = None
        device_uri_ret = None

        printers = device.getSupportedCUPSPrinterNames(back_end_filter, filter)
        log.debug(printers)

        if not printers:
            log.error("No device found that support this feature.")
            return False, None, None

        if device_uri is not None:
            devices = device.getSupportedCUPSDevices(back_end_filter, filter)
            if device_uri in devices:
                device_uri_ok = True
                device_uri_ret = device_uri
            else:
                log.error("'%s' device doesn't support this feature (or) Invalid device URI" % device_uri)
                device_uri = None
                if restrict_to_installed_devices:
                    return False, None, None

        if printer_name is not None:
            if printer_name == '*':
                from prnt import cups
                default_printer = cups.getDefaultPrinter()
                if default_printer is not None:
                    printer_name_ret = default_printer
                else:
                    log.error("CUPS default printer not set")
                    printer_name = None

            else:
                if printer_name.lower() in [p.lower() for p in printers]:
                    printer_name_ok = True
                    device_uri_ret = device.getDeviceURIByPrinterName(printer_name)
                else:
                    log.error("'%s' device doesn't support this feature (or) Invalid printer name" % printer_name)
                    printer_name = None
                    if restrict_to_installed_devices:
                        return False, None, None

        if device_uri is not None and printer_name is None and device_uri_ok: # Only device_uri specified
            if len(devices[device_uri]) == 1:
                printer_name_ret = devices[device_uri][0]

        elif device_uri is not None and printer_name is not None: # Both specified
            if device_uri_ok and printer_name_ok:
                if device_uri == device_uri_ret:
                    printer_name_ret = printer_name
                else:
                    log.error("Printer name and device URI refer to different devices.")

        elif device_uri is None and printer_name is not None and printer_name_ok: # Only printer name specified
            printer_name_ret = printer_name

        elif len(printers) == 1: # nothing specified, and only 1 avail. printer
            printer_name_ret = printers[0]

        if printer_name_ret is None and self.mode in (INTERACTIVE_MODE, NON_INTERACTIVE_MODE) and len(printers):
            printer_name_ret = tui.printer_table(printers)

        if printer_name_ret is not None and device_uri_ret is None:
            device_uri_ret = device.getDeviceURIByPrinterName(printer_name_ret)

        if device_uri_ret is not None:
            user_conf.set('last_used', 'device_uri', device_uri_ret)

        if printer_name_ret is not None:
            user_conf.set('last_used', 'printer_name', printer_name_ret)

        else:
            if self.mode in (INTERACTIVE_MODE, NON_INTERACTIVE_MODE):
                log.error("No printer selected/specified or that supports this functionality.")
                sys.exit(1)
            else:
                log.debug("No printer selected/specified")

        return True, printer_name_ret, device_uri_ret


    def lockInstance(self, suffix='',suppress_error=False):
        if suffix:
            ok, self.lock_file = utils.lock_app('-'.join([self.mod, suffix]),suppress_error)
        else:
            ok, self.lock_file = utils.lock_app(self.mod,suppress_error)

        if not ok:
            sys.exit(1)


    def unlockInstance(self):
        if self.lock_file is not None:
            utils.unlock(self.lock_file)