This file is indexed.

/usr/lib/python3/dist-packages/pyvisa/util.py is in python3-pyvisa 1.8-2.

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
# -*- coding: utf-8 -*-
"""
    pyvisa.util
    ~~~~~~~~~~~

    General utility functions.

    This file is part of PyVISA.

    :copyright: 2014 by PyVISA Authors, see AUTHORS for more details.
    :license: MIT, see LICENSE for more details.
"""

from __future__ import division, unicode_literals, print_function, absolute_import

import functools
import io
import os
import platform
import sys
import subprocess
import warnings

from .compat import check_output, string_types, OrderedDict, struct
from . import __version__, logger


def read_user_library_path():
    """Return the library path stored in one of the following configuration files:

        <sys prefix>/share/pyvisa/.pyvisarc
        ~/.pyvisarc

    <sys prefix> is the site-specific directory prefix where the platform
    independent Python files are installed.

    Example configuration file:

        [Paths]
        visa library=/my/path/visa.so

    Return `None` if  configuration files or keys are not present.

    """
    try:
        from ConfigParser import SafeConfigParser as ConfigParser, NoSectionError
    except ImportError:
        from configparser import ConfigParser, NoSectionError

    config_parser = ConfigParser()
    files = config_parser.read([os.path.join(sys.prefix, "share", "pyvisa", ".pyvisarc"),
                                os.path.join(os.path.expanduser("~"), ".pyvisarc")])

    if not files:
        logger.debug('No user defined library files')
        return None

    logger.debug('User defined library files: %s' % files)
    try:
        return config_parser.get("Paths", "visa library")
    except (KeyError, NoSectionError):
        logger.debug('KeyError or NoSectionError while reading config file')
        return None


class LibraryPath(str):

    #: Architectural information (32, ) or (64, ) or (32, 64)
    _arch = None

    def __new__(cls, path, found_by='auto'):
        obj = super(LibraryPath, cls).__new__(cls, path)
        obj.path = path
        obj.found_by = found_by

        return obj

    @property
    def arch(self):
        if self._arch is None:
            try:
                self._arch = get_arch(self.path)
            except:
                self._arch = tuple()

        return self._arch

    @property
    def is_32bit(self):
        if not self.arch:
            return 'n/a'
        return 32 in self.arch

    @property
    def is_64bit(self):
        if not self.arch:
            return 'n/a'
        return 64 in self.arch

    @property
    def bitness(self):
        if not self.arch:
            return 'n/a'
        return ', '.join(str(a) for a in self.arch)


def warn_for_invalid_kwargs(keyw, allowed_keys):
    for key in keyw.keys():
        if key not in allowed_keys:
            warnings.warn('Keyword argument "%s" unknown' % key, stacklevel=3)


def filter_kwargs(keyw, selected_keys):
    result = {}
    for key, value in keyw.items():
        if key in selected_keys:
            result[key] = value
    return result


def split_kwargs(keyw, self_keys, parent_keys, warn=True):
    self_kwargs = dict()
    parent_kwargs = dict()
    self_keys = set(self_keys)
    parent_keys = set(parent_keys)
    all_keys = self_keys | parent_keys
    for key, value in keyw.items():
        if warn and key not in all_keys:
            warnings.warn('Keyword argument "%s" unknown' % key, stacklevel=3)
        if key in self_keys:
            self_kwargs[key] = value
        if key in parent_keys:
            parent_kwargs[key] = value

    return self_kwargs, parent_kwargs


_converters = {
    's': str,
    'b': functools.partial(int, base=2),
    'c': chr,
    'd': int,
    'o': functools.partial(int, base=8),
    'x': functools.partial(int, base=16),
    'X': functools.partial(int, base=16),
    'e': float,
    'E': float,
    'f': float,
    'F': float,
    'g': float,
    'G': float,
}


def from_ascii_block(ascii_data, converter='f', separator=',', container=list):
    """Parse ascii data and return an iterable of numbers.

    :param ascii_data: data to be parsed.
    :type ascii_data: str
    :param converter: function used to convert each value.
                      Defaults to float
    :type converter: callable
    :param separator: a callable that split the str into individual elements.
                      If a str is given, data.split(separator) is used.
    :type: separator: (str) -> collections.Iterable[T] | str
    :param container: container type to use for the output data.
    """

    if isinstance(converter, string_types):
        try:
            converter = _converters[converter]
        except KeyError:
            raise ValueError('Invalid code for converter: %s not in %s' % (converter, str(tuple(_converters.keys()))))

    if isinstance(separator, string_types):
        data = ascii_data.split(separator)
    else:
        data = separator(ascii_data)

    return container([converter(raw_value) for raw_value in data])


def to_ascii_block(iterable, converter='f', separator=','):
    """Parse ascii data and return an iterable of numbers.

    :param iterable: data to be parsed.
    :type iterable: collections.Iterable[T]
    :param converter: function used to convert each value.
                      String formatting codes are also accepted.
                      Defaults to str.
    :type converter: callable | str
    :param separator: a callable that split the str into individual elements.
                      If a str is given, data.split(separator) is used.
    :type: separator: (collections.Iterable[T]) -> str | str
    """

    if isinstance(separator, string_types):
        separator = separator.join

    if isinstance(converter, string_types):
        converter = '%' + converter
        return separator(converter % val for val in iterable)
    else:
        return separator(converter(val) for val in iterable)


def parse_binary(bytes_data, is_big_endian=False, is_single=False):
    """Parse ascii data and return an iterable of numbers.

    To be deprecated in 1.7

    :param bytes_data: data to be parsed.
    :param is_big_endian: boolean indicating the endianness.
    :param is_single: boolean indicating the type (if not is double)
    :return:
    """
    data = bytes_data

    hash_sign_position = bytes_data.find(b"#")
    if hash_sign_position == -1:
        raise ValueError('Could not find valid hash position')

    if hash_sign_position > 0:
        data = data[hash_sign_position:]

    data_1 = data[1:2].decode('ascii')

    if data_1.isdigit() and int(data_1) > 0:
        number_of_digits = int(data_1)
        # I store data and data_length in two separate variables in case
        # that data is too short.  FixMe: Maybe I should raise an error if
        # it's too long and the trailing part is not just CR/LF.
        data_length = int(data[2:2 + number_of_digits])
        data = data[2 + number_of_digits:2 + number_of_digits + data_length]
    else:
        data = data[2:]
        if data[-1:].decode('ascii') == "\n":
            data = data[:-1]
        data_length = len(data)

    if is_big_endian:
        endianess = ">"
    else:
        endianess = "<"

    try:
        if is_single:
            fmt = endianess + str(data_length // 4) + 'f'
        else:
            fmt = endianess + str(data_length // 8) + 'd'

        result = list(struct.unpack(fmt, data))
    except struct.error:
        raise ValueError("Binary data itself was malformed")

    return result


def parse_ieee_block_header(block):
    """Parse the header of a IEEE block.

    Definite Length Arbitrary Block:
    #<header_length><data_length><data>

    The header_length specifies the size of the data_length field.
    And the data_length field specifies the size of the data.

    Indefinite Length Arbitrary Block:
    #0<data>

    :param block: IEEE block.
    :type block: bytes
    :return: (offset, data_length)
    :rtype: (int, int)
    """
    begin = block.find(b'#')
    if begin < 0:
        raise ValueError("Could not find hash sign (#) indicating the start of the block.")

    try:
        # int(block[begin+1]) != int(block[begin+1:begin+2]) in Python 3
        header_length = int(block[begin+1:begin+2])
    except ValueError:
        header_length = 0

    offset = begin + 2 + header_length

    if header_length > 0:
        # #3100DATA
        # 012345
        data_length = int(block[begin+2:offset])
    else:
        # #0DATA
        # 012
        data_length = len(block) - offset - 1

    return offset, data_length


def from_ieee_block(block, datatype='f', is_big_endian=False, container=list):
    """Convert a block in the IEEE format into an iterable of numbers.

    Definite Length Arbitrary Block:
    #<header_length><data_length><data>

    The header_length specifies the size of the data_length field.
    And the data_length field specifies the size of the data.

    Indefinite Length Arbitrary Block:
    #0<data>

    :param block: IEEE block.
    :type block: bytes
    :param datatype: the format string for a single element. See struct module.
    :param is_big_endian: boolean indicating endianess.
    :param container: container type to use for the output data.
    :return: items
    :rtype: type(container)
    """

    offset, data_length = parse_ieee_block_header(block)

    if len(block) < offset + data_length:
        raise ValueError("Binary data is incomplete. The header states %d data bytes, "
                         "but %d where received." % (data_length, len(block) - offset))

    return from_binary_block(block, offset, data_length, datatype, is_big_endian, container)


def from_binary_block(block, offset=0, data_length=None, datatype='f', is_big_endian=False, container=list):
    """Convert a binary block into an iterable of numbers.

    :param block: binary block.
    :type block: bytes
    :param offset: offset at which the data block starts (default=0)
    :param data_length: size in bytes of the data block (default=len(block) - offset)
    :param datatype: the format string for a single element. See struct module.
    :param is_big_endian: boolean indicating endianess.
    :param container: container type to use for the output data.
    :return: items
    :rtype: type(container)
    """

    if data_length is None:
        data_length = len(block) - offset

    element_length = struct.calcsize(datatype)
    array_length = int(data_length / element_length)

    endianess = '>' if is_big_endian else '<'

    fullfmt = '%s%d%s' % (endianess, array_length, datatype)

    try:
        return container(struct.unpack_from(fullfmt, block, offset))
    except struct.error:
        raise ValueError("Binary data was malformed")


def to_ieee_block(iterable, datatype='f', is_big_endian=False):
    """Convert an iterable of numbers into a block of data in the IEEE format.

    :param iterable: an iterable of numbers.
    :param datatype: the format string for a single element. See struct module.
    :param is_big_endian: boolean indicating endianess.
    :return: IEEE block.
    :rtype: bytes
    """

    array_length = len(iterable)
    element_length = struct.calcsize(datatype)
    data_length = array_length * element_length

    header = '%d' % data_length
    header = '#%d%s'%(len(header),header)

    endianess = '>' if is_big_endian else '<'
    fullfmt = '%s%d%s' % (endianess, array_length, datatype)

    if sys.version >= '3':
        return bytes(header, 'ascii') + struct.pack(fullfmt, *iterable)
    else:
        return str(header) + struct.pack(fullfmt, *iterable)


def get_system_details(backends=True):
    """Return a dictionary with information about the system
    """
    buildno, builddate = platform.python_build()
    if sys.maxunicode == 65535:
        # UCS2 build (standard)
        unitype = 'UCS2'
    else:
        # UCS4 build (most recent Linux distros)
        unitype = 'UCS4'
    bits, linkage = platform.architecture()

    d = {
        'platform': platform.platform(),
        'processor': platform.processor(),
        'executable': sys.executable,
        'implementation': getattr(platform, 'python_implementation',
                                  lambda: 'n/a')(),
        'python': platform.python_version(),
        'compiler': platform.python_compiler(),
        'buildno': buildno,
        'builddate': builddate,
        'unicode': unitype,
        'bits': bits,
        'pyvisa': __version__,
        'backends': OrderedDict()
    }

    if backends:
        from . import highlevel
        for backend in highlevel.list_backends():
            if backend.startswith('pyvisa-'):
                backend = backend[7:]

            try:
                cls = highlevel.get_wrapper_class(backend)
            except Exception as e:
                d['backends'][backend] = ['Could not instantiate backend',
                                          '-> %s' % str(e)]
                continue

            try:
                d['backends'][backend] = cls.get_debug_info()
            except Exception as e:
                d['backends'][backend] = ['Could not obtain debug info',
                                          '-> %s' % str(e)]

    return d


def system_details_to_str(d, indent=''):
    """Return a str with the system details.
    """

    l = ['Machine Details:',
         '   Platform ID:    %s' % d.get('platform', 'n/a'),
         '   Processor:      %s' % d.get('processor', 'n/a'),
         '',
         'Python:',
         '   Implementation: %s' % d.get('implementation', 'n/a'),
         '   Executable:     %s' % d.get('executable', 'n/a'),
         '   Version:        %s' % d.get('python', 'n/a'),
         '   Compiler:       %s' % d.get('compiler', 'n/a'),
         '   Bits:           %s' % d.get('bits', 'n/a'),
         '   Build:          %s (#%s)' % (d.get('builddate', 'n/a'),
                                          d.get('buildno', 'n/a')),
         '   Unicode:        %s' % d.get('unicode', 'n/a'),
         '',
         'PyVISA Version: %s' % d.get('pyvisa', 'n/a'),
         '',
         ]

    def _to_list(key, value, indent_level=0):
        sp = ' ' * indent_level * 3

        if isinstance(value, string_types):
            if key:
                return ['%s%s: %s' % (sp, key, value)]
            else:
                return ['%s%s' % (sp, value)]

        elif isinstance(value, dict):
            if key:
                al = ['%s%s:' % (sp, key)]
            else:
                al = []

            for k, v in value.items():
                al.extend(_to_list(k, v, indent_level+1))
            return al

        elif isinstance(value, (tuple, list)):
            if key:
                al = ['%s%s:' % (sp, key)]
            else:
                al = []

            for v in value:
                al.extend(_to_list(None, v, indent_level+1))

            return al

    l.extend(_to_list('Backends', d['backends']))

    joiner = '\n' + indent
    return indent + joiner.join(l) + '\n'


def get_debug_info(to_screen=True):
    out = system_details_to_str(get_system_details())
    if not to_screen:
        return out
    print(out)


def pip_install(package):
    try:
        # noinspection PyPackageRequirements,PyUnresolvedReferences
        import pip
        return pip.main(['install', package])
    except ImportError:
        print(system_details_to_str(get_system_details()))
        raise RuntimeError('Please install pip to continue.')


machine_types = {
    0: 'UNKNOWN',
    0x014c: 'I386',
    0x0162: 'R3000',
    0x0166: 'R4000',
    0x0168: 'R10000',
    0x0169: 'WCEMIPSV2',
    0x0184: 'ALPHA',
    0x01a2: 'SH3',
    0x01a3: 'SH3DSP',
    0x01a4: 'SH3E',
    0x01a6: 'SH4',
    0x01a8: 'SH5',
    0x01c0: 'ARM',
    0x01c2: 'THUMB',
    0x01c4: 'ARMNT',
    0x01d3: 'AM33',
    0x01f0: 'POWERPC',
    0x01f1: 'POWERPCFP',
    0x0200: 'IA64',
    0x0266: 'MIPS16',
    0x0284: 'ALPHA64',
    #0x0284: 'AXP64', # same
    0x0366: 'MIPSFPU',
    0x0466: 'MIPSFPU16',
    0x0520: 'TRICORE',
    0x0cef: 'CEF',
    0x0ebc: 'EBC',
    0x8664: 'AMD64',
    0x9041: 'M32R',
    0xc0ee: 'CEE',
}


def get_shared_library_arch(filename):
    with io.open(filename, 'rb') as fp:
        dos_headers = fp.read(64)
        _ = fp.read(4)

        magic, skip, offset = struct.unpack(str('2s58sl'), dos_headers)

        if magic != b'MZ':
            raise Exception('Not an executable')

        fp.seek(offset, io.SEEK_SET)
        pe_header = fp.read(6)

        sig, skip, machine = struct.unpack(str('2s2sH'), pe_header)

        if sig != b'PE':
            raise Exception('Not a PE executable')

        return machine_types.get(machine, 'UNKNOWN')


def get_arch(filename):
    this_platform = sys.platform
    if this_platform.startswith('win'):
        machine_type = get_shared_library_arch(filename)
        if machine_type == 'I386':
            return 32,
        elif machine_type in ('IA64', 'AMD64'):
            return 64,
        else:
            return ()
    elif not this_platform in ('linux2', 'linux3', 'linux', 'darwin'):
        raise OSError('')

    out = check_output(["file", filename], stderr=subprocess.STDOUT)
    out = out.decode('ascii')
    ret = []
    if this_platform.startswith('linux'):
        if '32-bit' in out:
            ret.append(32)
        if '64-bit' in out:
            ret.append(64)
    elif this_platform == 'darwin':
        if '(for architecture i386)' in out:
            ret.append(32)
        if '(for architecture x86_64)' in out:
            ret.append(64)

    return tuple(ret)