summaryrefslogblamecommitdiff
path: root/tools/utils/libconf.py
blob: 635efd07d65941a2651e4a00256806ac51efd749 (plain) (tree)
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
689
690
691
692
693




















































































































































































































































































































































































































































































































































































































































































































                                                                                                 
#!/usr/bin/python
# -*- coding: utf8 -*-
#
# Copyright (C) 2018 Hercules Dev Team
#
# This library 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 3 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, see <http://www.gnu.org/licenses/>.

# This file originally licensed under the MIT License
#
# Copyright (c) 2016 Christian Aichinger <Greek0@gmx.net>
# https://github.com/Grk0/python-libconf
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the "Software"), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
# of the Software, and to permit persons to whom the Software is furnished to do
# so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

from __future__ import absolute_import, division, print_function

import sys
import os
import codecs
import collections
import io
import re

# Define an isstr() and isint() that work on both Python2 and Python3.
# See http://stackoverflow.com/questions/11301138
try:
    basestring  # attempt to evaluate basestring

    def isstr(s):
        return isinstance(s, basestring)

    def isint(i):
        return isinstance(i, (int, long))
except NameError:

    def isstr(s):
        return isinstance(s, str)

    def isint(i):
        return isinstance(i, int)

# Bounds to determine when an "L" suffix should be used during dump().
SMALL_INT_MIN = -2**31
SMALL_INT_MAX = 2**31 - 1

ESCAPE_SEQUENCE_RE = re.compile(r'''
    ( \\x..            # 2-digit hex escapes
    | \\[\\'"abfnrtv]  # Single-character escapes
    )''', re.UNICODE | re.VERBOSE)

SKIP_RE = re.compile(r'\s+|#.*$|//.*$|/\*(.|\n)*?\*/', re.MULTILINE)
UNPRINTABLE_CHARACTER_RE = re.compile(r'[\x00-\x1F\x7F]')


# load() logic
##############

def decode_escapes(s):
    '''Unescape libconfig string literals'''
    def decode_match(match):
        return codecs.decode(match.group(0), 'unicode-escape')

    return ESCAPE_SEQUENCE_RE.sub(decode_match, s)


class AttrDict(collections.OrderedDict):
    '''OrderedDict subclass giving access to string keys via attribute access

    This class derives from collections.OrderedDict. Thus, the original
    order of the config entries in the input stream is maintained.
    '''

    def __getattr__(self, attr):
        if attr == '_OrderedDict__root':
            # Work around Python2's OrderedDict weirdness.
            raise AttributeError("AttrDict has no attribute %r" % attr)
        return self.__getitem__(attr)


class ConfigParseError(RuntimeError):
    '''Exception class raised on errors reading the libconfig input'''
    pass


class ConfigSerializeError(TypeError):
    '''Exception class raised on errors serializing a config object'''
    pass


class Token(object):
    '''Base class for all tokens produced by the libconf tokenizer'''
    def __init__(self, type, text, filename, row, column):
        self.type = type
        self.text = text
        self.filename = filename
        self.row = row
        self.column = column

    def __str__(self):
        return "%r in %r, row %d, column %d" % (
            self.text, self.filename, self.row, self.column)


class FltToken(Token):
    '''Token subclass for floating point values'''
    def __init__(self, *args, **kwargs):
        super(FltToken, self).__init__(*args, **kwargs)
        self.value = float(self.text)


class IntToken(Token):
    '''Token subclass for integral values'''
    def __init__(self, *args, **kwargs):
        super(IntToken, self).__init__(*args, **kwargs)
        self.is_long = self.text.endswith('L')
        self.is_hex = (self.text[1:2].lower() == 'x')
        self.value = int(self.text.rstrip('L'), 0)


class BoolToken(Token):
    '''Token subclass for booleans'''
    def __init__(self, *args, **kwargs):
        super(BoolToken, self).__init__(*args, **kwargs)
        self.value = (self.text[0].lower() == 't')


class StrToken(Token):
    '''Token subclass for strings'''
    def __init__(self, *args, **kwargs):
        super(StrToken, self).__init__(*args, **kwargs)
        self.value = decode_escapes(self.text[1:-1])


def compile_regexes(token_map):
    return [(cls, type, re.compile(regex))
            for cls, type, regex in token_map]


class Tokenizer:
    '''Tokenize an input string

    Typical usage:

        tokens = list(Tokenizer("<memory>").tokenize("""a = 7; b = ();"""))

    The filename argument to the constructor is used only in error messages, no
    data is loaded from the file. The input data is received as argument to the
    tokenize function, which yields tokens or throws a ConfigParseError on
    invalid input.

    Include directives are not supported, they must be handled at a higher
    level (cf. the TokenStream class).
    '''

    token_map = compile_regexes([
        (FltToken,  'float',     r'([-+]?(\d+)?\.\d*([eE][-+]?\d+)?)|'
                                 r'([-+]?(\d+)(\.\d*)?[eE][-+]?\d+)'),
        (IntToken,  'hex64',     r'0[Xx][0-9A-Fa-f]+(L(L)?)'),
        (IntToken,  'hex',       r'0[Xx][0-9A-Fa-f]+'),
        (BoolToken, 'boolean',   r'(?i)(true|false)\b'),
        (StrToken,  'string',    r'"([^"\\]|\\.)*"'),
        (StrToken,  'string',    r'<"(?<=<")([\S\s]*?)(?=">)">'),
        (Token,     'name',      r'[0-9]*[A-Za-z\*][-A-Za-z0-9_\*]*'),
        (IntToken,  'integer64', r'[-+]?[0-9]+L(L)?'),
        (IntToken,  'integer',   r'[-+]?[0-9]+'),
        (Token,     '}',         r'\}'),
        (Token,     '{',         r'\{'),
        (Token,     ')',         r'\)'),
        (Token,     '(',         r'\('),
        (Token,     ']',         r'\]'),
        (Token,     '[',         r'\['),
        (Token,     ',',         r','),
        (Token,     ';',         r';'),
        (Token,     '=',         r'='),
        (Token,     ':',         r':'),
    ])

    def __init__(self, filename):
        self.filename = filename
        self.row = 1
        self.column = 1

    def tokenize(self, string):
        '''Yield tokens from the input string or throw ConfigParseError'''
        pos = 0
        while pos < len(string):
            m = SKIP_RE.match(string, pos=pos)
            if m:
                skip_lines = m.group(0).split('\n')
                if len(skip_lines) > 1:
                    self.row += len(skip_lines) - 1
                    self.column = 1 + len(skip_lines[-1])
                else:
                    self.column += len(skip_lines[0])

                pos = m.end()
                continue

            for cls, type, regex in self.token_map:
                m = regex.match(string, pos=pos)
                if m:
                    yield cls(type, m.group(0),
                              self.filename, self.row, self.column)
                    self.column += len(m.group(0))
                    pos = m.end()
                    break
            else:
                raise ConfigParseError(
                    "Couldn't load config in %r row %d, column %d: %r" %
                    (self.filename, self.row, self.column,
                     string[pos:pos+20]))


class TokenStream:
    '''Offer a parsing-oriented view on tokens

    Provide several methods that are useful to parsers, like ``accept()``,
    ``expect()``, ...

    The ``from_file()`` method is the preferred way to read input files, as
    it handles include directives, which the ``Tokenizer`` class does not do.
    '''

    def __init__(self, tokens):
        self.position = 0
        self.tokens = list(tokens)

    @classmethod
    def from_file(cls, f, filename=None, includedir='', seenfiles=None):
        '''Create a token stream by reading an input file

        Read tokens from `f`. If an include directive ('@include "file.cfg"')
        is found, read its contents as well.

        The `filename` argument is used for error messages and to detect
        circular imports. ``includedir`` sets the lookup directory for included
        files.  ``seenfiles`` is used internally to detect circular includes,
        and should normally not be supplied by users of is function.
        '''

        if filename is None:
            filename = getattr(f, 'name', '<unknown>')
        if seenfiles is None:
            seenfiles = set()

        if filename in seenfiles:
            raise ConfigParseError("Circular include: %r" % (filename,))
        seenfiles = seenfiles | {filename}  # Copy seenfiles, don't alter it.

        tokenizer = Tokenizer(filename=filename)
        lines = []
        tokens = []
        for line in f:
            m = re.match(r'@include "(.*)"$', line.strip())
            if m:
                tokens.extend(tokenizer.tokenize(''.join(lines)))
                lines = [re.sub(r'\S', ' ', line)]

                includefilename = decode_escapes(m.group(1))
                includefilename = os.path.join(includedir, includefilename)
                try:
                    includefile = open(includefilename, "r")
                except IOError:
                    raise ConfigParseError("Could not open include file %r" %
                                           (includefilename,))

                with includefile:
                    includestream = cls.from_file(includefile,
                                                  filename=includefilename,
                                                  includedir=includedir,
                                                  seenfiles=seenfiles)
                tokens.extend(includestream.tokens)

            else:
                lines.append(line)

        tokens.extend(tokenizer.tokenize(''.join(lines)))
        return cls(tokens)

    def peek(self):
        '''Return (but do not consume) the next token

        At the end of input, ``None`` is returned.
        '''

        if self.position >= len(self.tokens):
            return None

        return self.tokens[self.position]

    def accept(self, *args):
        '''Consume and return the next token if it has the correct type

        Multiple token types (as strings, e.g. 'integer64') can be given
        as arguments. If the next token is one of them, consume and return it.

        If the token type doesn't match, return None.
        '''

        token = self.peek()
        if token is None:
            return None

        for arg in args:
            if token.type == arg:
                self.position += 1
                return token

        return None

    def expect(self, *args):
        '''Consume and return the next token if it has the correct type

        Multiple token types (as strings, e.g. 'integer64') can be given
        as arguments. If the next token is one of them, consume and return it.

        If the token type doesn't match, raise a ConfigParseError.
        '''

        t = self.accept(*args)
        if t is not None:
            return t

        self.error("expected: %r" % (args,))

    def error(self, msg):
        '''Raise a ConfigParseError at the current input position'''
        if self.finished():
            raise ConfigParseError("Unexpected end of input; %s" % (msg,))
        else:
            t = self.peek()
            raise ConfigParseError("Unexpected token %s; %s" % (t, msg))

    def finished(self):
        '''Return ``True`` if the end of the token stream is reached.'''
        return self.position >= len(self.tokens)


class Parser:
    '''Recursive descent parser for libconfig files

    Takes a ``TokenStream`` as input, the ``parse()`` method then returns
    the config file data in a ``json``-module-style format.
    '''

    def __init__(self, tokenstream):
        self.tokens = tokenstream

    def parse(self):
        return self.configuration()

    def configuration(self):
        result = self.setting_list_or_empty()
        if not self.tokens.finished():
            raise ConfigParseError("Expected end of input but found %s" %
                                   (self.tokens.peek(),))

        return result

    def setting_list_or_empty(self):
        result = AttrDict()
        while True:
            s = self.setting()
            if s is None:
                return result

            result[s[0]] = s[1]

    def setting(self):
        name = self.tokens.accept('name')
        if name is None:
            return None

        self.tokens.expect(':', '=')

        value = self.value()
        if value is None:
            self.tokens.error("expected a value")

        self.tokens.accept(';', ',')

        return (name.text, value)

    def value(self):
        acceptable = [self.scalar_value, self.array, self.list, self.group]
        return self._parse_any_of(acceptable)

    def scalar_value(self):
        # This list is ordered so that more common tokens are checked first.
        acceptable = [self.string, self.boolean, self.integer, self.float,
                      self.hex, self.integer64, self.hex64]
        return self._parse_any_of(acceptable)

    def value_list_or_empty(self):
        return tuple(self._comma_separated_list_or_empty(self.value))

    def scalar_value_list_or_empty(self):
        return self._comma_separated_list_or_empty(self.scalar_value)

    def array(self):
        return self._enclosed_block('[', self.scalar_value_list_or_empty, ']')

    def list(self):
        return self._enclosed_block('(', self.value_list_or_empty, ')')

    def group(self):
        return self._enclosed_block('{', self.setting_list_or_empty, '}')

    def boolean(self):
        return self._create_value_node('boolean')

    def integer(self):
        return self._create_value_node('integer')

    def integer64(self):
        return self._create_value_node('integer64')

    def hex(self):
        return self._create_value_node('hex')

    def hex64(self):
        return self._create_value_node('hex64')

    def float(self):
        return self._create_value_node('float')

    def string(self):
        t_first = self.tokens.accept('string')
        if t_first is None:
            return None

        values = [t_first.value]
        while True:
            t = self.tokens.accept('string')
            if t is None:
                break
            values.append(t.value)

        return ''.join(values)

    def _create_value_node(self, tokentype):
        t = self.tokens.accept(tokentype)
        if t is None:
            return None

        return t.value

    def _parse_any_of(self, nonterminals):
        for fun in nonterminals:
            result = fun()
            if result is not None:
                return result

        return None

    def _comma_separated_list_or_empty(self, nonterminal):
        values = []
        first = True
        while True:
            v = nonterminal()
            if v is None:
                if first:
                    return []
                else:
                # This is disabled to enable the last member in a list to have a comma at the end
                #   self.tokens.error("expected value after ','")
                    return values

            values.append(v)
            if not self.tokens.accept(','):
                return values

            first = False

    def _enclosed_block(self, start, nonterminal, end):
        if not self.tokens.accept(start):
            return None
        result = nonterminal()
        self.tokens.expect(end)
        return result


def load(f, filename=None, includedir=''):
    '''Load the contents of ``f`` (a file-like object) to a Python object

    The returned object is a subclass of ``dict`` that exposes string keys as
    attributes as well.

    Example:

        >>> with open('test/example.cfg') as f:
        ...     config = libconf.load(f)
        >>> config['window']['title']
        'libconfig example'
        >>> config.window.title
        'libconfig example'
    '''

    if isinstance(f.read(0), bytes):
        raise TypeError("libconf.load() input file must by unicode")

    tokenstream = TokenStream.from_file(f,
                                        filename=filename,
                                        includedir=includedir)
    return Parser(tokenstream).parse()


def loads(string, filename=None, includedir=''):
    '''Load the contents of ``string`` to a Python object

    The returned object is a subclass of ``dict`` that exposes string keys as
    attributes as well.

    Example:

        >>> config = libconf.loads('window: { title: "libconfig example"; };')
        >>> config['window']['title']
        'libconfig example'
        >>> config.window.title
        'libconfig example'
    '''

    try:
        f = io.StringIO(string)
    except TypeError:
        raise TypeError("libconf.loads() input string must by unicode")

    return load(f, filename=filename, includedir=includedir)


# dump() logic
##############

def dump_int(i):
    '''Stringize ``i``, append 'L' if ``i`` is exceeds the 32-bit int range'''
    return str(i) + ('' if SMALL_INT_MIN <= i <= SMALL_INT_MAX else 'L')


def dump_string(s):
    '''Stringize ``s``, adding double quotes and escaping as necessary

    Backslash escape backslashes, double quotes, ``\f``, ``\n``, ``\r``, and
    ``\t``. Escape all remaining unprintable characters in ``\xFF``-style.
    The returned string will be surrounded by double quotes.
    '''

    s = (s.replace('\\', '\\\\')
          .replace('"', '\\"')
          .replace('\f', r'\f')
          .replace('\n', r'\n')
          .replace('\r', r'\r')
          .replace('\t', r'\t'))
    s = UNPRINTABLE_CHARACTER_RE.sub(
            lambda m: r'\x{:02x}'.format(ord(m.group(0))),
            s)
    return '"' + s + '"'


def dump_value(key, value, f, indent=0):
    '''Save a value of any libconfig type

    This function serializes takes ``key`` and ``value`` and serializes them
    into ``f``. If ``key`` is ``None``, a list-style output is produced.
    Otherwise, output has ``key = value`` format.
    '''

    spaces = ' ' * indent

    if key is None:
        key_prefix = ''
        key_prefix_nl = ''
    else:
        key_prefix = key + ' = '
        key_prefix_nl = key + ' =\n' + spaces

    if isinstance(value, dict):
        f.write(u'{}{}{{\n'.format(spaces, key_prefix_nl))
        dump_dict(value, f, indent + 4)
        f.write(u'{}}}'.format(spaces))
    elif isinstance(value, tuple):
        f.write(u'{}{}(\n'.format(spaces, key_prefix_nl))
        dump_collection(value, f, indent + 4)
        f.write(u'\n{})'.format(spaces))
    elif isinstance(value, list):
        f.write(u'{}{}[\n'.format(spaces, key_prefix_nl))
        dump_collection(value, f, indent + 4)
        f.write(u'\n{}]'.format(spaces))
    elif isstr(value):
        f.write(u'{}{}{}'.format(spaces, key_prefix, dump_string(value)))
    elif isint(value):
        f.write(u'{}{}{}'.format(spaces, key_prefix, dump_int(value)))
    elif isinstance(value, float):
        f.write(u'{}{}{}'.format(spaces, key_prefix, value))
    else:
        raise ConfigSerializeError("Can not serialize object %r of type %s" %
                                   (value, type(value)))


def dump_collection(cfg, f, indent=0):
    '''Save a collection of attributes'''

    for i, value in enumerate(cfg):
        dump_value(None, value, f, indent)
        if i < len(cfg) - 1:
            f.write(u',\n')


def dump_dict(cfg, f, indent=0):
    '''Save a dictionary of attributes'''

    for key in cfg:
        if not isstr(key):
            raise ConfigSerializeError("Dict keys must be strings: %r" %
                                       (key,))
        dump_value(key, cfg[key], f, indent)
        f.write(u';\n')


def dumps(cfg):
    '''Serialize ``cfg`` into a libconfig-formatted ``str``

    ``cfg`` must be a ``dict`` with ``str`` keys and libconf-supported values
    (numbers, strings, booleans, possibly nested dicts, lists, and tuples).

    Returns the formatted string.
    '''

    str_file = io.StringIO()
    dump(cfg, str_file)
    return str_file.getvalue()


def dump(cfg, f):
    '''Serialize ``cfg`` as a libconfig-formatted stream into ``f``

    ``cfg`` must be a ``dict`` with ``str`` keys and libconf-supported values
    (numbers, strings, booleans, possibly nested dicts, lists, and tuples).

    ``f`` must be a ``file``-like object with a ``write()`` method.
    '''

    if not isinstance(cfg, dict):
        raise ConfigSerializeError(
                'dump() requires a dict as input, not %r of type %r' %
                (cfg, type(cfg)))

    dump_dict(cfg, f, 0)


# main(): small example of how to use libconf
#############################################

def main():
    '''Open the libconfig file specified by sys.argv[1] and pretty-print it'''
    global output
    if len(sys.argv[1:]) == 1:
        with io.open(sys.argv[1], 'r', encoding='utf-8') as f:
            output = load(f)
    else:
        output = load(sys.stdin)

    dump(output, sys.stdout)


if __name__ == '__main__':
    main()