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71aaa3f7 PP |
1 | # The MIT License (MIT) |
2 | # | |
3 | # Copyright (c) 2023 Philippe Proulx <eeppeliteloop@gmail.com> | |
4 | # | |
5 | # Permission is hereby granted, free of charge, to any person obtaining | |
6 | # a copy of this software and associated documentation files (the | |
7 | # "Software"), to deal in the Software without restriction, including | |
8 | # without limitation the rights to use, copy, modify, merge, publish, | |
9 | # distribute, sublicense, and/or sell copies of the Software, and to | |
10 | # permit persons to whom the Software is furnished to do so, subject to | |
11 | # the following conditions: | |
12 | # | |
13 | # The above copyright notice and this permission notice shall be | |
14 | # included in all copies or substantial portions of the Software. | |
15 | # | |
16 | # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | |
17 | # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | |
18 | # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. | |
19 | # IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY | |
20 | # CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, | |
21 | # TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE | |
22 | # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | |
23 | ||
5a993698 PP |
24 | # This module is the portable Normand processor. It offers both the |
25 | # parse() function and the command-line tool (run the module itself) | |
26 | # without external dependencies except a `typing` module for Python 3.4. | |
27 | # | |
28 | # Feel free to copy this module file to your own project to use Normand. | |
29 | # | |
30 | # Upstream repository: <https://github.com/efficios/normand>. | |
31 | ||
71aaa3f7 | 32 | __author__ = "Philippe Proulx" |
2adf4336 | 33 | __version__ = "0.3.0" |
71aaa3f7 PP |
34 | __all__ = [ |
35 | "ByteOrder", | |
36 | "parse", | |
37 | "ParseError", | |
38 | "ParseResult", | |
39 | "TextLoc", | |
40 | "VarsT", | |
41 | "__author__", | |
42 | "__version__", | |
43 | ] | |
44 | ||
45 | import re | |
46 | import abc | |
47 | import ast | |
48 | import sys | |
49 | import enum | |
50 | import struct | |
2adf4336 PP |
51 | from typing import ( |
52 | Any, | |
53 | Set, | |
54 | Dict, | |
55 | List, | |
56 | Tuple, | |
57 | Union, | |
58 | Pattern, | |
59 | Callable, | |
60 | NoReturn, | |
61 | Optional, | |
62 | ) | |
71aaa3f7 PP |
63 | |
64 | ||
65 | # Text location (line and column numbers). | |
66 | class TextLoc: | |
67 | @classmethod | |
68 | def _create(cls, line_no: int, col_no: int): | |
69 | self = cls.__new__(cls) | |
70 | self._init(line_no, col_no) | |
71 | return self | |
72 | ||
73 | def __init__(*args, **kwargs): # type: ignore | |
74 | raise NotImplementedError | |
75 | ||
76 | def _init(self, line_no: int, col_no: int): | |
77 | self._line_no = line_no | |
78 | self._col_no = col_no | |
79 | ||
80 | # Line number. | |
81 | @property | |
82 | def line_no(self): | |
83 | return self._line_no | |
84 | ||
85 | # Column number. | |
86 | @property | |
87 | def col_no(self): | |
88 | return self._col_no | |
89 | ||
2adf4336 PP |
90 | def __repr__(self): |
91 | return "TextLoc({}, {})".format(self._line_no, self._col_no) | |
92 | ||
71aaa3f7 PP |
93 | |
94 | # Any item. | |
95 | class _Item: | |
96 | def __init__(self, text_loc: TextLoc): | |
97 | self._text_loc = text_loc | |
98 | ||
99 | # Source text location. | |
100 | @property | |
101 | def text_loc(self): | |
102 | return self._text_loc | |
103 | ||
2adf4336 PP |
104 | |
105 | # Scalar item. | |
106 | class _ScalarItem(_Item): | |
71aaa3f7 PP |
107 | # Returns the size, in bytes, of this item. |
108 | @property | |
109 | @abc.abstractmethod | |
110 | def size(self) -> int: | |
111 | ... | |
112 | ||
113 | ||
114 | # A repeatable item. | |
2adf4336 | 115 | class _RepableItem: |
71aaa3f7 PP |
116 | pass |
117 | ||
118 | ||
119 | # Single byte. | |
2adf4336 | 120 | class _Byte(_ScalarItem, _RepableItem): |
71aaa3f7 PP |
121 | def __init__(self, val: int, text_loc: TextLoc): |
122 | super().__init__(text_loc) | |
123 | self._val = val | |
124 | ||
125 | # Byte value. | |
126 | @property | |
127 | def val(self): | |
128 | return self._val | |
129 | ||
130 | @property | |
131 | def size(self): | |
132 | return 1 | |
133 | ||
134 | def __repr__(self): | |
135 | return "_Byte({}, {})".format(hex(self._val), self._text_loc) | |
136 | ||
137 | ||
138 | # String. | |
2adf4336 | 139 | class _Str(_ScalarItem, _RepableItem): |
71aaa3f7 PP |
140 | def __init__(self, data: bytes, text_loc: TextLoc): |
141 | super().__init__(text_loc) | |
142 | self._data = data | |
143 | ||
144 | # Encoded bytes. | |
145 | @property | |
146 | def data(self): | |
147 | return self._data | |
148 | ||
149 | @property | |
150 | def size(self): | |
151 | return len(self._data) | |
152 | ||
153 | def __repr__(self): | |
154 | return "_Str({}, {})".format(repr(self._data), self._text_loc) | |
155 | ||
156 | ||
157 | # Byte order. | |
158 | @enum.unique | |
159 | class ByteOrder(enum.Enum): | |
160 | # Big endian. | |
161 | BE = "be" | |
162 | ||
163 | # Little endian. | |
164 | LE = "le" | |
165 | ||
166 | ||
2adf4336 PP |
167 | # Byte order setting. |
168 | class _SetBo(_Item): | |
0e8e3169 PP |
169 | def __init__(self, bo: ByteOrder, text_loc: TextLoc): |
170 | super().__init__(text_loc) | |
71aaa3f7 PP |
171 | self._bo = bo |
172 | ||
173 | @property | |
174 | def bo(self): | |
175 | return self._bo | |
176 | ||
2adf4336 PP |
177 | def __repr__(self): |
178 | return "_SetBo({}, {})".format(repr(self._bo), self._text_loc) | |
71aaa3f7 PP |
179 | |
180 | ||
181 | # Label. | |
182 | class _Label(_Item): | |
183 | def __init__(self, name: str, text_loc: TextLoc): | |
184 | super().__init__(text_loc) | |
185 | self._name = name | |
186 | ||
187 | # Label name. | |
188 | @property | |
189 | def name(self): | |
190 | return self._name | |
191 | ||
71aaa3f7 PP |
192 | def __repr__(self): |
193 | return "_Label({}, {})".format(repr(self._name), self._text_loc) | |
194 | ||
195 | ||
2adf4336 PP |
196 | # Offset setting. |
197 | class _SetOffset(_Item): | |
71aaa3f7 PP |
198 | def __init__(self, val: int, text_loc: TextLoc): |
199 | super().__init__(text_loc) | |
200 | self._val = val | |
201 | ||
202 | # Offset value. | |
203 | @property | |
204 | def val(self): | |
205 | return self._val | |
206 | ||
71aaa3f7 | 207 | def __repr__(self): |
2adf4336 | 208 | return "_SetOffset({}, {})".format(repr(self._val), self._text_loc) |
71aaa3f7 PP |
209 | |
210 | ||
211 | # Mixin of containing an AST expression and its string. | |
212 | class _ExprMixin: | |
213 | def __init__(self, expr_str: str, expr: ast.Expression): | |
214 | self._expr_str = expr_str | |
215 | self._expr = expr | |
216 | ||
217 | # Expression string. | |
218 | @property | |
219 | def expr_str(self): | |
220 | return self._expr_str | |
221 | ||
222 | # Expression node to evaluate. | |
223 | @property | |
224 | def expr(self): | |
225 | return self._expr | |
226 | ||
227 | ||
2adf4336 PP |
228 | # Variable assignment. |
229 | class _VarAssign(_Item, _ExprMixin): | |
71aaa3f7 PP |
230 | def __init__( |
231 | self, name: str, expr_str: str, expr: ast.Expression, text_loc: TextLoc | |
232 | ): | |
233 | super().__init__(text_loc) | |
234 | _ExprMixin.__init__(self, expr_str, expr) | |
235 | self._name = name | |
236 | ||
237 | # Name. | |
238 | @property | |
239 | def name(self): | |
240 | return self._name | |
241 | ||
71aaa3f7 | 242 | def __repr__(self): |
2adf4336 | 243 | return "_VarAssign({}, {}, {}, {})".format( |
71aaa3f7 PP |
244 | repr(self._name), repr(self._expr_str), repr(self._expr), self._text_loc |
245 | ) | |
246 | ||
247 | ||
248 | # Value, possibly needing more than one byte. | |
2adf4336 | 249 | class _Val(_ScalarItem, _RepableItem, _ExprMixin): |
71aaa3f7 PP |
250 | def __init__( |
251 | self, expr_str: str, expr: ast.Expression, len: int, text_loc: TextLoc | |
252 | ): | |
253 | super().__init__(text_loc) | |
254 | _ExprMixin.__init__(self, expr_str, expr) | |
255 | self._len = len | |
256 | ||
257 | # Length (bits). | |
258 | @property | |
259 | def len(self): | |
260 | return self._len | |
261 | ||
262 | @property | |
263 | def size(self): | |
264 | return self._len // 8 | |
265 | ||
266 | def __repr__(self): | |
267 | return "_Val({}, {}, {}, {})".format( | |
268 | repr(self._expr_str), repr(self._expr), repr(self._len), self._text_loc | |
269 | ) | |
270 | ||
271 | ||
71aaa3f7 | 272 | # Group of items. |
2adf4336 | 273 | class _Group(_Item, _RepableItem): |
71aaa3f7 PP |
274 | def __init__(self, items: List[_Item], text_loc: TextLoc): |
275 | super().__init__(text_loc) | |
276 | self._items = items | |
71aaa3f7 PP |
277 | |
278 | # Contained items. | |
279 | @property | |
280 | def items(self): | |
281 | return self._items | |
282 | ||
71aaa3f7 PP |
283 | def __repr__(self): |
284 | return "_Group({}, {})".format(repr(self._items), self._text_loc) | |
285 | ||
286 | ||
287 | # Repetition item. | |
2adf4336 PP |
288 | class _Rep(_Item, _ExprMixin): |
289 | def __init__( | |
290 | self, item: _Item, expr_str: str, expr: ast.Expression, text_loc: TextLoc | |
291 | ): | |
71aaa3f7 | 292 | super().__init__(text_loc) |
2adf4336 | 293 | _ExprMixin.__init__(self, expr_str, expr) |
71aaa3f7 | 294 | self._item = item |
71aaa3f7 PP |
295 | |
296 | # Item to repeat. | |
297 | @property | |
298 | def item(self): | |
299 | return self._item | |
300 | ||
71aaa3f7 | 301 | def __repr__(self): |
2adf4336 PP |
302 | return "_Rep({}, {}, {}, {})".format( |
303 | repr(self._item), repr(self._expr_str), repr(self._expr), self._text_loc | |
71aaa3f7 PP |
304 | ) |
305 | ||
306 | ||
2adf4336 PP |
307 | # Expression item type. |
308 | _ExprItemT = Union[_Val, _VarAssign, _Rep] | |
309 | ||
310 | ||
71aaa3f7 PP |
311 | # A parsing error containing a message and a text location. |
312 | class ParseError(RuntimeError): | |
313 | @classmethod | |
314 | def _create(cls, msg: str, text_loc: TextLoc): | |
315 | self = cls.__new__(cls) | |
316 | self._init(msg, text_loc) | |
317 | return self | |
318 | ||
319 | def __init__(self, *args, **kwargs): # type: ignore | |
320 | raise NotImplementedError | |
321 | ||
322 | def _init(self, msg: str, text_loc: TextLoc): | |
323 | super().__init__(msg) | |
324 | self._text_loc = text_loc | |
325 | ||
326 | # Source text location. | |
327 | @property | |
328 | def text_loc(self): | |
329 | return self._text_loc | |
330 | ||
331 | ||
332 | # Raises a parsing error, forwarding the parameters to the constructor. | |
333 | def _raise_error(msg: str, text_loc: TextLoc) -> NoReturn: | |
334 | raise ParseError._create(msg, text_loc) # pyright: ignore[reportPrivateUsage] | |
335 | ||
336 | ||
2adf4336 | 337 | # Variable/label dictionary type. |
71aaa3f7 PP |
338 | VarsT = Dict[str, int] |
339 | ||
340 | ||
341 | # Python name pattern. | |
342 | _py_name_pat = re.compile(r"[a-zA-Z_][a-zA-Z0-9_]*") | |
343 | ||
344 | ||
345 | # Normand parser. | |
346 | # | |
347 | # The constructor accepts a Normand input. After building, use the `res` | |
348 | # property to get the resulting main group. | |
349 | class _Parser: | |
350 | # Builds a parser to parse the Normand input `normand`, parsing | |
351 | # immediately. | |
352 | def __init__(self, normand: str, variables: VarsT, labels: VarsT): | |
353 | self._normand = normand | |
354 | self._at = 0 | |
355 | self._line_no = 1 | |
356 | self._col_no = 1 | |
357 | self._label_names = set(labels.keys()) | |
358 | self._var_names = set(variables.keys()) | |
359 | self._parse() | |
360 | ||
361 | # Result (main group). | |
362 | @property | |
363 | def res(self): | |
364 | return self._res | |
365 | ||
366 | # Current text location. | |
367 | @property | |
368 | def _text_loc(self): | |
369 | return TextLoc._create( # pyright: ignore[reportPrivateUsage] | |
370 | self._line_no, self._col_no | |
371 | ) | |
372 | ||
373 | # Returns `True` if this parser is done parsing. | |
374 | def _is_done(self): | |
375 | return self._at == len(self._normand) | |
376 | ||
377 | # Returns `True` if this parser isn't done parsing. | |
378 | def _isnt_done(self): | |
379 | return not self._is_done() | |
380 | ||
381 | # Raises a parse error, creating it using the message `msg` and the | |
382 | # current text location. | |
383 | def _raise_error(self, msg: str) -> NoReturn: | |
384 | _raise_error(msg, self._text_loc) | |
385 | ||
386 | # Tries to make the pattern `pat` match the current substring, | |
387 | # returning the match object and updating `self._at`, | |
388 | # `self._line_no`, and `self._col_no` on success. | |
389 | def _try_parse_pat(self, pat: Pattern[str]): | |
390 | m = pat.match(self._normand, self._at) | |
391 | ||
392 | if m is None: | |
393 | return | |
394 | ||
395 | # Skip matched string | |
396 | self._at += len(m.group(0)) | |
397 | ||
398 | # Update line number | |
399 | self._line_no += m.group(0).count("\n") | |
400 | ||
401 | # Update column number | |
402 | for i in reversed(range(self._at)): | |
403 | if self._normand[i] == "\n" or i == 0: | |
404 | if i == 0: | |
405 | self._col_no = self._at + 1 | |
406 | else: | |
407 | self._col_no = self._at - i | |
408 | ||
409 | break | |
410 | ||
411 | # Return match object | |
412 | return m | |
413 | ||
414 | # Expects the pattern `pat` to match the current substring, | |
415 | # returning the match object and updating `self._at`, | |
416 | # `self._line_no`, and `self._col_no` on success, or raising a parse | |
417 | # error with the message `error_msg` on error. | |
418 | def _expect_pat(self, pat: Pattern[str], error_msg: str): | |
419 | # Match | |
420 | m = self._try_parse_pat(pat) | |
421 | ||
422 | if m is None: | |
423 | # No match: error | |
424 | self._raise_error(error_msg) | |
425 | ||
426 | # Return match object | |
427 | return m | |
428 | ||
429 | # Pattern for _skip_ws_and_comments() | |
430 | _ws_or_syms_or_comments_pat = re.compile( | |
431 | r"(?:[\s!@/\\?&:;.,+[\]_=|-]|#[^#]*?(?:\n|#))*" | |
432 | ) | |
433 | ||
434 | # Skips as many whitespaces, insignificant symbol characters, and | |
435 | # comments as possible. | |
436 | def _skip_ws_and_comments(self): | |
437 | self._try_parse_pat(self._ws_or_syms_or_comments_pat) | |
438 | ||
439 | # Pattern for _try_parse_hex_byte() | |
440 | _nibble_pat = re.compile(r"[A-Fa-f0-9]") | |
441 | ||
442 | # Tries to parse a hexadecimal byte, returning a byte item on | |
443 | # success. | |
444 | def _try_parse_hex_byte(self): | |
0e8e3169 PP |
445 | begin_text_loc = self._text_loc |
446 | ||
71aaa3f7 PP |
447 | # Match initial nibble |
448 | m_high = self._try_parse_pat(self._nibble_pat) | |
449 | ||
450 | if m_high is None: | |
451 | # No match | |
452 | return | |
453 | ||
454 | # Expect another nibble | |
455 | self._skip_ws_and_comments() | |
456 | m_low = self._expect_pat( | |
457 | self._nibble_pat, "Expecting another hexadecimal nibble" | |
458 | ) | |
459 | ||
460 | # Return item | |
0e8e3169 | 461 | return _Byte(int(m_high.group(0) + m_low.group(0), 16), begin_text_loc) |
71aaa3f7 PP |
462 | |
463 | # Patterns for _try_parse_bin_byte() | |
464 | _bin_byte_bit_pat = re.compile(r"[01]") | |
465 | _bin_byte_prefix_pat = re.compile(r"%") | |
466 | ||
467 | # Tries to parse a binary byte, returning a byte item on success. | |
468 | def _try_parse_bin_byte(self): | |
0e8e3169 PP |
469 | begin_text_loc = self._text_loc |
470 | ||
71aaa3f7 PP |
471 | # Match prefix |
472 | if self._try_parse_pat(self._bin_byte_prefix_pat) is None: | |
473 | # No match | |
474 | return | |
475 | ||
476 | # Expect eight bits | |
477 | bits = [] # type: List[str] | |
478 | ||
479 | for _ in range(8): | |
480 | self._skip_ws_and_comments() | |
481 | m = self._expect_pat(self._bin_byte_bit_pat, "Expecting a bit (`0` or `1`)") | |
482 | bits.append(m.group(0)) | |
483 | ||
484 | # Return item | |
0e8e3169 | 485 | return _Byte(int("".join(bits), 2), begin_text_loc) |
71aaa3f7 PP |
486 | |
487 | # Patterns for _try_parse_dec_byte() | |
488 | _dec_byte_prefix_pat = re.compile(r"\$\s*") | |
489 | _dec_byte_val_pat = re.compile(r"(?P<neg>-?)(?P<val>\d+)") | |
490 | ||
491 | # Tries to parse a decimal byte, returning a byte item on success. | |
492 | def _try_parse_dec_byte(self): | |
0e8e3169 PP |
493 | begin_text_loc = self._text_loc |
494 | ||
71aaa3f7 PP |
495 | # Match prefix |
496 | if self._try_parse_pat(self._dec_byte_prefix_pat) is None: | |
497 | # No match | |
498 | return | |
499 | ||
500 | # Expect the value | |
501 | m = self._expect_pat(self._dec_byte_val_pat, "Expecting a decimal constant") | |
502 | ||
503 | # Compute value | |
504 | val = int(m.group("val")) * (-1 if m.group("neg") == "-" else 1) | |
505 | ||
506 | # Validate | |
507 | if val < -128 or val > 255: | |
0e8e3169 | 508 | _raise_error("Invalid decimal byte value {}".format(val), begin_text_loc) |
71aaa3f7 PP |
509 | |
510 | # Two's complement | |
511 | val = val % 256 | |
512 | ||
513 | # Return item | |
0e8e3169 | 514 | return _Byte(val, begin_text_loc) |
71aaa3f7 PP |
515 | |
516 | # Tries to parse a byte, returning a byte item on success. | |
517 | def _try_parse_byte(self): | |
518 | # Hexadecimal | |
519 | item = self._try_parse_hex_byte() | |
520 | ||
521 | if item is not None: | |
522 | return item | |
523 | ||
524 | # Binary | |
525 | item = self._try_parse_bin_byte() | |
526 | ||
527 | if item is not None: | |
528 | return item | |
529 | ||
530 | # Decimal | |
531 | item = self._try_parse_dec_byte() | |
532 | ||
533 | if item is not None: | |
534 | return item | |
535 | ||
536 | # Patterns for _try_parse_str() | |
537 | _str_prefix_pat = re.compile(r'(?:u(?P<len>16|32)(?P<bo>be|le))?\s*"') | |
538 | _str_suffix_pat = re.compile(r'"') | |
539 | _str_str_pat = re.compile(r'(?:(?:\\.)|[^"])*') | |
540 | ||
541 | # Strings corresponding to escape sequence characters | |
542 | _str_escape_seq_strs = { | |
543 | "0": "\0", | |
544 | "a": "\a", | |
545 | "b": "\b", | |
546 | "e": "\x1b", | |
547 | "f": "\f", | |
548 | "n": "\n", | |
549 | "r": "\r", | |
550 | "t": "\t", | |
551 | "v": "\v", | |
552 | "\\": "\\", | |
553 | '"': '"', | |
554 | } | |
555 | ||
556 | # Tries to parse a string, returning a string item on success. | |
557 | def _try_parse_str(self): | |
0e8e3169 PP |
558 | begin_text_loc = self._text_loc |
559 | ||
71aaa3f7 PP |
560 | # Match prefix |
561 | m = self._try_parse_pat(self._str_prefix_pat) | |
562 | ||
563 | if m is None: | |
564 | # No match | |
565 | return | |
566 | ||
567 | # Get encoding | |
568 | encoding = "utf8" | |
569 | ||
570 | if m.group("len") is not None: | |
571 | encoding = "utf_{}_{}".format(m.group("len"), m.group("bo")) | |
572 | ||
573 | # Actual string | |
574 | m = self._expect_pat(self._str_str_pat, "Expecting a literal string") | |
575 | ||
576 | # Expect end of string | |
577 | self._expect_pat(self._str_suffix_pat, 'Expecting `"` (end of literal string)') | |
578 | ||
579 | # Replace escape sequences | |
580 | val = m.group(0) | |
581 | ||
582 | for ec in '0abefnrtv"\\': | |
583 | val = val.replace(r"\{}".format(ec), self._str_escape_seq_strs[ec]) | |
584 | ||
585 | # Encode | |
586 | data = val.encode(encoding) | |
587 | ||
588 | # Return item | |
0e8e3169 | 589 | return _Str(data, begin_text_loc) |
71aaa3f7 PP |
590 | |
591 | # Patterns for _try_parse_group() | |
592 | _group_prefix_pat = re.compile(r"\(") | |
593 | _group_suffix_pat = re.compile(r"\)") | |
594 | ||
595 | # Tries to parse a group, returning a group item on success. | |
596 | def _try_parse_group(self): | |
0e8e3169 PP |
597 | begin_text_loc = self._text_loc |
598 | ||
71aaa3f7 PP |
599 | # Match prefix |
600 | if self._try_parse_pat(self._group_prefix_pat) is None: | |
601 | # No match | |
602 | return | |
603 | ||
604 | # Parse items | |
605 | items = self._parse_items() | |
606 | ||
607 | # Expect end of group | |
608 | self._skip_ws_and_comments() | |
609 | self._expect_pat( | |
610 | self._group_suffix_pat, "Expecting an item or `)` (end of group)" | |
611 | ) | |
612 | ||
613 | # Return item | |
0e8e3169 | 614 | return _Group(items, begin_text_loc) |
71aaa3f7 PP |
615 | |
616 | # Returns a stripped expression string and an AST expression node | |
617 | # from the expression string `expr_str` at text location `text_loc`. | |
618 | def _ast_expr_from_str(self, expr_str: str, text_loc: TextLoc): | |
619 | # Create an expression node from the expression string | |
620 | expr_str = expr_str.strip().replace("\n", " ") | |
621 | ||
622 | try: | |
623 | expr = ast.parse(expr_str, mode="eval") | |
624 | except SyntaxError: | |
625 | _raise_error( | |
626 | "Invalid expression `{}`: invalid syntax".format(expr_str), | |
627 | text_loc, | |
628 | ) | |
629 | ||
630 | return expr_str, expr | |
631 | ||
632 | # Patterns for _try_parse_val_and_len() | |
633 | _val_expr_pat = re.compile(r"([^}:]+):") | |
634 | _val_len_pat = re.compile(r"\s*(8|16|24|32|40|48|56|64)") | |
635 | ||
636 | # Tries to parse a value and length, returning a value item on | |
637 | # success. | |
638 | def _try_parse_val_and_len(self): | |
639 | begin_text_loc = self._text_loc | |
640 | ||
641 | # Match | |
642 | m_expr = self._try_parse_pat(self._val_expr_pat) | |
643 | ||
644 | if m_expr is None: | |
645 | # No match | |
646 | return | |
647 | ||
648 | # Expect a length | |
649 | m_len = self._expect_pat( | |
650 | self._val_len_pat, "Expecting a length (multiple of eight bits)" | |
651 | ) | |
652 | ||
653 | # Create an expression node from the expression string | |
654 | expr_str, expr = self._ast_expr_from_str(m_expr.group(1), begin_text_loc) | |
655 | ||
656 | # Return item | |
657 | return _Val( | |
658 | expr_str, | |
659 | expr, | |
660 | int(m_len.group(1)), | |
0e8e3169 | 661 | begin_text_loc, |
71aaa3f7 PP |
662 | ) |
663 | ||
664 | # Patterns for _try_parse_val_and_len() | |
2adf4336 | 665 | _var_assign_pat = re.compile( |
71aaa3f7 PP |
666 | r"(?P<name>{})\s*=\s*(?P<expr>[^}}]+)".format(_py_name_pat.pattern) |
667 | ) | |
668 | ||
2adf4336 PP |
669 | # Tries to parse a variable assignment, returning a variable |
670 | # assignment item on success. | |
671 | def _try_parse_var_assign(self): | |
71aaa3f7 PP |
672 | begin_text_loc = self._text_loc |
673 | ||
674 | # Match | |
2adf4336 | 675 | m = self._try_parse_pat(self._var_assign_pat) |
71aaa3f7 PP |
676 | |
677 | if m is None: | |
678 | # No match | |
679 | return | |
680 | ||
681 | # Validate name | |
682 | name = m.group("name") | |
683 | ||
684 | if name == _icitte_name: | |
0e8e3169 PP |
685 | _raise_error( |
686 | "`{}` is a reserved variable name".format(_icitte_name), begin_text_loc | |
687 | ) | |
71aaa3f7 PP |
688 | |
689 | if name in self._label_names: | |
0e8e3169 | 690 | _raise_error("Existing label named `{}`".format(name), begin_text_loc) |
71aaa3f7 PP |
691 | |
692 | # Add to known variable names | |
693 | self._var_names.add(name) | |
694 | ||
695 | # Create an expression node from the expression string | |
696 | expr_str, expr = self._ast_expr_from_str(m.group("expr"), begin_text_loc) | |
697 | ||
698 | # Return item | |
2adf4336 | 699 | return _VarAssign( |
71aaa3f7 PP |
700 | name, |
701 | expr_str, | |
702 | expr, | |
0e8e3169 | 703 | begin_text_loc, |
71aaa3f7 PP |
704 | ) |
705 | ||
2adf4336 | 706 | # Pattern for _try_parse_set_bo() |
71aaa3f7 PP |
707 | _bo_pat = re.compile(r"[bl]e") |
708 | ||
2adf4336 PP |
709 | # Tries to parse a byte order name, returning a byte order setting |
710 | # item on success. | |
711 | def _try_parse_set_bo(self): | |
0e8e3169 PP |
712 | begin_text_loc = self._text_loc |
713 | ||
71aaa3f7 PP |
714 | # Match |
715 | m = self._try_parse_pat(self._bo_pat) | |
716 | ||
717 | if m is None: | |
718 | # No match | |
719 | return | |
720 | ||
721 | # Return corresponding item | |
722 | if m.group(0) == "be": | |
2adf4336 | 723 | return _SetBo(ByteOrder.BE, begin_text_loc) |
71aaa3f7 PP |
724 | else: |
725 | assert m.group(0) == "le" | |
2adf4336 | 726 | return _SetBo(ByteOrder.LE, begin_text_loc) |
71aaa3f7 PP |
727 | |
728 | # Patterns for _try_parse_val_or_bo() | |
2adf4336 PP |
729 | _val_var_assign_set_bo_prefix_pat = re.compile(r"\{\s*") |
730 | _val_var_assign_set_bo_suffix_pat = re.compile(r"\s*}") | |
71aaa3f7 | 731 | |
2adf4336 PP |
732 | # Tries to parse a value, a variable assignment, or a byte order |
733 | # setting, returning an item on success. | |
734 | def _try_parse_val_or_var_assign_or_set_bo(self): | |
71aaa3f7 | 735 | # Match prefix |
2adf4336 | 736 | if self._try_parse_pat(self._val_var_assign_set_bo_prefix_pat) is None: |
71aaa3f7 PP |
737 | # No match |
738 | return | |
739 | ||
2adf4336 PP |
740 | # Variable assignment item? |
741 | item = self._try_parse_var_assign() | |
71aaa3f7 PP |
742 | |
743 | if item is None: | |
744 | # Value item? | |
745 | item = self._try_parse_val_and_len() | |
746 | ||
747 | if item is None: | |
2adf4336 PP |
748 | # Byte order setting item? |
749 | item = self._try_parse_set_bo() | |
71aaa3f7 PP |
750 | |
751 | if item is None: | |
752 | # At this point it's invalid | |
2adf4336 PP |
753 | self._raise_error( |
754 | "Expecting a value, a variable assignment, or a byte order setting" | |
755 | ) | |
71aaa3f7 PP |
756 | |
757 | # Expect suffix | |
2adf4336 | 758 | self._expect_pat(self._val_var_assign_set_bo_suffix_pat, "Expecting `}`") |
71aaa3f7 PP |
759 | return item |
760 | ||
2adf4336 | 761 | # Pattern for _try_parse_set_offset_val() and _try_parse_rep() |
71aaa3f7 PP |
762 | _pos_const_int_pat = re.compile(r"0[Xx][A-Fa-f0-9]+|\d+") |
763 | ||
2adf4336 PP |
764 | # Tries to parse an offset setting value (after the initial `<`), |
765 | # returning an offset item on success. | |
766 | def _try_parse_set_offset_val(self): | |
0e8e3169 PP |
767 | begin_text_loc = self._text_loc |
768 | ||
71aaa3f7 PP |
769 | # Match |
770 | m = self._try_parse_pat(self._pos_const_int_pat) | |
771 | ||
772 | if m is None: | |
773 | # No match | |
774 | return | |
775 | ||
776 | # Return item | |
2adf4336 | 777 | return _SetOffset(int(m.group(0), 0), begin_text_loc) |
71aaa3f7 PP |
778 | |
779 | # Tries to parse a label name (after the initial `<`), returning a | |
780 | # label item on success. | |
781 | def _try_parse_label_name(self): | |
0e8e3169 PP |
782 | begin_text_loc = self._text_loc |
783 | ||
71aaa3f7 PP |
784 | # Match |
785 | m = self._try_parse_pat(_py_name_pat) | |
786 | ||
787 | if m is None: | |
788 | # No match | |
789 | return | |
790 | ||
791 | # Validate | |
792 | name = m.group(0) | |
793 | ||
794 | if name == _icitte_name: | |
0e8e3169 PP |
795 | _raise_error( |
796 | "`{}` is a reserved label name".format(_icitte_name), begin_text_loc | |
797 | ) | |
71aaa3f7 PP |
798 | |
799 | if name in self._label_names: | |
0e8e3169 | 800 | _raise_error("Duplicate label name `{}`".format(name), begin_text_loc) |
71aaa3f7 PP |
801 | |
802 | if name in self._var_names: | |
0e8e3169 | 803 | _raise_error("Existing variable named `{}`".format(name), begin_text_loc) |
71aaa3f7 PP |
804 | |
805 | # Add to known label names | |
806 | self._label_names.add(name) | |
807 | ||
808 | # Return item | |
0e8e3169 | 809 | return _Label(name, begin_text_loc) |
71aaa3f7 | 810 | |
2adf4336 PP |
811 | # Patterns for _try_parse_label_or_set_offset() |
812 | _label_set_offset_prefix_pat = re.compile(r"<\s*") | |
813 | _label_set_offset_suffix_pat = re.compile(r"\s*>") | |
71aaa3f7 | 814 | |
2adf4336 PP |
815 | # Tries to parse a label or an offset setting, returning an item on |
816 | # success. | |
817 | def _try_parse_label_or_set_offset(self): | |
71aaa3f7 | 818 | # Match prefix |
2adf4336 | 819 | if self._try_parse_pat(self._label_set_offset_prefix_pat) is None: |
71aaa3f7 PP |
820 | # No match |
821 | return | |
822 | ||
2adf4336 PP |
823 | # Offset setting item? |
824 | item = self._try_parse_set_offset_val() | |
71aaa3f7 PP |
825 | |
826 | if item is None: | |
827 | # Label item? | |
828 | item = self._try_parse_label_name() | |
829 | ||
830 | if item is None: | |
831 | # At this point it's invalid | |
2adf4336 | 832 | self._raise_error("Expecting a label name or an offset setting value") |
71aaa3f7 PP |
833 | |
834 | # Expect suffix | |
2adf4336 | 835 | self._expect_pat(self._label_set_offset_suffix_pat, "Expecting `>`") |
71aaa3f7 PP |
836 | return item |
837 | ||
838 | # Tries to parse a base item (anything except a repetition), | |
839 | # returning it on success. | |
840 | def _try_parse_base_item(self): | |
841 | # Byte item? | |
842 | item = self._try_parse_byte() | |
843 | ||
844 | if item is not None: | |
845 | return item | |
846 | ||
847 | # String item? | |
848 | item = self._try_parse_str() | |
849 | ||
850 | if item is not None: | |
851 | return item | |
852 | ||
2adf4336 PP |
853 | # Value, variable assignment, or byte order setting item? |
854 | item = self._try_parse_val_or_var_assign_or_set_bo() | |
71aaa3f7 PP |
855 | |
856 | if item is not None: | |
857 | return item | |
858 | ||
2adf4336 PP |
859 | # Label or offset setting item? |
860 | item = self._try_parse_label_or_set_offset() | |
71aaa3f7 PP |
861 | |
862 | if item is not None: | |
863 | return item | |
864 | ||
865 | # Group item? | |
866 | item = self._try_parse_group() | |
867 | ||
868 | if item is not None: | |
869 | return item | |
870 | ||
871 | # Pattern for _try_parse_rep() | |
872 | _rep_prefix_pat = re.compile(r"\*\s*") | |
2adf4336 PP |
873 | _rep_expr_prefix_pat = re.compile(r"\{") |
874 | _rep_expr_pat = re.compile(r"[^}p]+") | |
875 | _rep_expr_suffix_pat = re.compile(r"\}") | |
71aaa3f7 | 876 | |
2adf4336 PP |
877 | # Tries to parse a repetition, returning the expression string and |
878 | # AST expression node on success. | |
71aaa3f7 | 879 | def _try_parse_rep(self): |
71aaa3f7 PP |
880 | # Match prefix |
881 | if self._try_parse_pat(self._rep_prefix_pat) is None: | |
882 | # No match | |
2adf4336 | 883 | return |
71aaa3f7 PP |
884 | |
885 | # Expect and return a decimal multiplier | |
886 | self._skip_ws_and_comments() | |
2adf4336 PP |
887 | |
888 | # Integer? | |
889 | m = self._try_parse_pat(self._pos_const_int_pat) | |
890 | ||
891 | if m is None: | |
892 | # Expression? | |
893 | if self._try_parse_pat(self._rep_expr_prefix_pat) is None: | |
894 | # At this point it's invalid | |
895 | self._raise_error("Expecting a positive integral multiplier or `{`") | |
896 | ||
897 | # Expect an expression | |
898 | expr_str_loc = self._text_loc | |
899 | m = self._expect_pat(self._rep_expr_pat, "Expecting an expression") | |
900 | expr_str = self._ast_expr_from_str(m.group(0), expr_str_loc) | |
901 | ||
902 | # Expect `}` | |
903 | self._expect_pat(self._rep_expr_suffix_pat, "Expecting `}`") | |
904 | expr_str = m.group(0) | |
905 | else: | |
906 | expr_str_loc = self._text_loc | |
907 | expr_str = m.group(0) | |
908 | ||
909 | return self._ast_expr_from_str(expr_str, expr_str_loc) | |
71aaa3f7 | 910 | |
1ca7b5e1 PP |
911 | # Tries to parse an item, possibly followed by a repetition, |
912 | # returning `True` on success. | |
913 | # | |
914 | # Appends any parsed item to `items`. | |
915 | def _try_append_item(self, items: List[_Item]): | |
71aaa3f7 PP |
916 | self._skip_ws_and_comments() |
917 | ||
918 | # Parse a base item | |
919 | item = self._try_parse_base_item() | |
920 | ||
921 | if item is None: | |
922 | # No item | |
1ca7b5e1 | 923 | return False |
71aaa3f7 PP |
924 | |
925 | # Parse repetition if the base item is repeatable | |
926 | if isinstance(item, _RepableItem): | |
0e8e3169 PP |
927 | self._skip_ws_and_comments() |
928 | rep_text_loc = self._text_loc | |
2adf4336 | 929 | rep_ret = self._try_parse_rep() |
71aaa3f7 | 930 | |
2adf4336 PP |
931 | if rep_ret is not None: |
932 | item = _Rep(item, rep_ret[0], rep_ret[1], rep_text_loc) | |
71aaa3f7 | 933 | |
1ca7b5e1 PP |
934 | items.append(item) |
935 | return True | |
71aaa3f7 PP |
936 | |
937 | # Parses and returns items, skipping whitespaces, insignificant | |
938 | # symbols, and comments when allowed, and stopping at the first | |
939 | # unknown character. | |
940 | def _parse_items(self) -> List[_Item]: | |
941 | items = [] # type: List[_Item] | |
942 | ||
943 | while self._isnt_done(): | |
1ca7b5e1 PP |
944 | # Try to append item |
945 | if not self._try_append_item(items): | |
946 | # Unknown at this point | |
947 | break | |
71aaa3f7 PP |
948 | |
949 | return items | |
950 | ||
951 | # Parses the whole Normand input, setting `self._res` to the main | |
952 | # group item on success. | |
953 | def _parse(self): | |
954 | if len(self._normand.strip()) == 0: | |
955 | # Special case to make sure there's something to consume | |
956 | self._res = _Group([], self._text_loc) | |
957 | return | |
958 | ||
959 | # Parse first level items | |
960 | items = self._parse_items() | |
961 | ||
962 | # Make sure there's nothing left | |
963 | self._skip_ws_and_comments() | |
964 | ||
965 | if self._isnt_done(): | |
966 | self._raise_error( | |
967 | "Unexpected character `{}`".format(self._normand[self._at]) | |
968 | ) | |
969 | ||
970 | # Set main group item | |
971 | self._res = _Group(items, self._text_loc) | |
972 | ||
973 | ||
974 | # The return type of parse(). | |
975 | class ParseResult: | |
976 | @classmethod | |
977 | def _create( | |
978 | cls, | |
979 | data: bytearray, | |
980 | variables: VarsT, | |
981 | labels: VarsT, | |
982 | offset: int, | |
983 | bo: Optional[ByteOrder], | |
984 | ): | |
985 | self = cls.__new__(cls) | |
986 | self._init(data, variables, labels, offset, bo) | |
987 | return self | |
988 | ||
989 | def __init__(self, *args, **kwargs): # type: ignore | |
990 | raise NotImplementedError | |
991 | ||
992 | def _init( | |
993 | self, | |
994 | data: bytearray, | |
995 | variables: VarsT, | |
996 | labels: VarsT, | |
997 | offset: int, | |
998 | bo: Optional[ByteOrder], | |
999 | ): | |
1000 | self._data = data | |
1001 | self._vars = variables | |
1002 | self._labels = labels | |
1003 | self._offset = offset | |
1004 | self._bo = bo | |
1005 | ||
1006 | # Generated data. | |
1007 | @property | |
1008 | def data(self): | |
1009 | return self._data | |
1010 | ||
1011 | # Dictionary of updated variable names to their last computed value. | |
1012 | @property | |
1013 | def variables(self): | |
1014 | return self._vars | |
1015 | ||
1016 | # Dictionary of updated main group label names to their computed | |
1017 | # value. | |
1018 | @property | |
1019 | def labels(self): | |
1020 | return self._labels | |
1021 | ||
1022 | # Updated offset. | |
1023 | @property | |
1024 | def offset(self): | |
1025 | return self._offset | |
1026 | ||
1027 | # Updated byte order. | |
1028 | @property | |
1029 | def byte_order(self): | |
1030 | return self._bo | |
1031 | ||
1032 | ||
1033 | # Raises a parse error for the item `item`, creating it using the | |
1034 | # message `msg`. | |
1035 | def _raise_error_for_item(msg: str, item: _Item) -> NoReturn: | |
1036 | _raise_error(msg, item.text_loc) | |
1037 | ||
1038 | ||
1039 | # The `ICITTE` reserved name. | |
1040 | _icitte_name = "ICITTE" | |
1041 | ||
1042 | ||
2adf4336 PP |
1043 | # Base node visitor. |
1044 | # | |
1045 | # Calls the _visit_name() method for each name node which isn't the name | |
1046 | # of a call. | |
1047 | class _NodeVisitor(ast.NodeVisitor): | |
1048 | def __init__(self): | |
71aaa3f7 PP |
1049 | self._parent_is_call = False |
1050 | ||
1051 | def generic_visit(self, node: ast.AST): | |
1052 | if type(node) is ast.Call: | |
1053 | self._parent_is_call = True | |
1054 | elif type(node) is ast.Name and not self._parent_is_call: | |
2adf4336 | 1055 | self._visit_name(node.id) |
71aaa3f7 PP |
1056 | |
1057 | super().generic_visit(node) | |
1058 | self._parent_is_call = False | |
1059 | ||
2adf4336 PP |
1060 | @abc.abstractmethod |
1061 | def _visit_name(self, name: str): | |
1062 | ... | |
1063 | ||
71aaa3f7 | 1064 | |
2adf4336 PP |
1065 | # Expression validator: validates that all the names within the |
1066 | # expression are allowed. | |
1067 | class _ExprValidator(_NodeVisitor): | |
1068 | def __init__(self, item: _ExprItemT, allowed_names: Set[str], icitte_allowed: bool): | |
1069 | super().__init__() | |
1070 | self._item = item | |
1071 | self._allowed_names = allowed_names | |
1072 | self._icitte_allowed = icitte_allowed | |
1073 | ||
1074 | def _visit_name(self, name: str): | |
1075 | # Make sure the name refers to a known and reachable | |
1076 | # variable/label name. | |
1077 | if name == _icitte_name and not self._icitte_allowed: | |
1078 | _raise_error( | |
1079 | "Illegal reserved name `{}` in expression `{}`".format( | |
1080 | _icitte_name, self._item.expr_str | |
1081 | ), | |
1082 | self._item.text_loc, | |
1083 | ) | |
1084 | elif name != _icitte_name and name not in self._allowed_names: | |
1085 | msg = "Illegal (unknown or unreachable) variable/label name `{}` in expression `{}`".format( | |
1086 | name, self._item.expr_str | |
1087 | ) | |
1088 | ||
1089 | if len(self._allowed_names) > 0: | |
1090 | allowed_names = self._allowed_names.copy() | |
1091 | ||
1092 | if self._icitte_allowed: | |
1093 | allowed_names.add(_icitte_name) | |
1094 | ||
1095 | allowed_names_str = ", ".join( | |
1096 | sorted(["`{}`".format(name) for name in allowed_names]) | |
1097 | ) | |
1098 | msg += "; the legal names are {{{}}}".format(allowed_names_str) | |
1099 | ||
1100 | _raise_error( | |
1101 | msg, | |
1102 | self._item.text_loc, | |
1103 | ) | |
1104 | ||
1105 | ||
1106 | # Expression visitor getting all the contained names. | |
1107 | class _ExprNamesVisitor(_NodeVisitor): | |
71aaa3f7 | 1108 | def __init__(self): |
2adf4336 PP |
1109 | self._parent_is_call = False |
1110 | self._names = set() # type: Set[str] | |
1111 | ||
1112 | @property | |
1113 | def names(self): | |
1114 | return self._names | |
71aaa3f7 | 1115 | |
2adf4336 PP |
1116 | def _visit_name(self, name: str): |
1117 | self._names.add(name) | |
71aaa3f7 | 1118 | |
71aaa3f7 | 1119 | |
2adf4336 PP |
1120 | # Generator state. |
1121 | class _GenState: | |
1122 | def __init__( | |
1123 | self, variables: VarsT, labels: VarsT, offset: int, bo: Optional[ByteOrder] | |
1124 | ): | |
1125 | self.variables = variables.copy() | |
1126 | self.labels = labels.copy() | |
1127 | self.offset = offset | |
1128 | self.bo = bo | |
71aaa3f7 PP |
1129 | |
1130 | ||
2adf4336 | 1131 | # Generator of data and final state from a group item. |
71aaa3f7 PP |
1132 | # |
1133 | # Generation happens in memory at construction time. After building, use | |
1134 | # the `data`, `variables`, `labels`, `offset`, and `bo` properties to | |
1135 | # get the resulting context. | |
2adf4336 PP |
1136 | # |
1137 | # The steps of generation are: | |
1138 | # | |
1139 | # 1. Validate that each repetition expression uses only reachable names | |
1140 | # and not `ICITTE`. | |
1141 | # | |
1142 | # 2. Compute and keep the effective repetition count for each repetition | |
1143 | # instance. | |
1144 | # | |
1145 | # 3. Generate bytes, updating the initial state as it goes which becomes | |
1146 | # the final state after the operation. | |
1147 | # | |
1148 | # During the generation, when handling a `_Rep` item, we already have | |
1149 | # the effective repetition count of the instance. | |
1150 | # | |
1151 | # When handling a `_Group` item, first update the current labels with | |
1152 | # all the immediate (not nested) labels, and then handle each | |
1153 | # contained item. This gives contained item access to "future" outer | |
1154 | # labels. Then remove the immediate labels from the state so that | |
1155 | # outer items don't have access to inner labels. | |
71aaa3f7 PP |
1156 | class _Gen: |
1157 | def __init__( | |
1158 | self, | |
1159 | group: _Group, | |
1160 | variables: VarsT, | |
1161 | labels: VarsT, | |
1162 | offset: int, | |
1163 | bo: Optional[ByteOrder], | |
1164 | ): | |
2adf4336 PP |
1165 | self._validate_rep_exprs(group, set(variables.keys()), set(labels.keys())) |
1166 | self._rep_instance_vals = self._compute_rep_instance_vals( | |
1167 | group, _GenState(variables, labels, offset, bo) | |
1168 | ) | |
1169 | self._gen(group, _GenState(variables, labels, offset, bo)) | |
71aaa3f7 PP |
1170 | |
1171 | # Generated bytes. | |
1172 | @property | |
1173 | def data(self): | |
1174 | return self._data | |
1175 | ||
1176 | # Updated variables. | |
1177 | @property | |
1178 | def variables(self): | |
2adf4336 | 1179 | return self._final_state.variables |
71aaa3f7 PP |
1180 | |
1181 | # Updated main group labels. | |
1182 | @property | |
1183 | def labels(self): | |
2adf4336 | 1184 | return self._final_state.labels |
71aaa3f7 PP |
1185 | |
1186 | # Updated offset. | |
1187 | @property | |
1188 | def offset(self): | |
2adf4336 | 1189 | return self._final_state.offset |
71aaa3f7 PP |
1190 | |
1191 | # Updated byte order. | |
1192 | @property | |
1193 | def bo(self): | |
2adf4336 PP |
1194 | return self._final_state.bo |
1195 | ||
1196 | # Returns the set of used, non-called names within the AST | |
1197 | # expression `expr`. | |
1198 | @staticmethod | |
1199 | def _names_of_expr(expr: ast.Expression): | |
1200 | visitor = _ExprNamesVisitor() | |
1201 | visitor.visit(expr) | |
1202 | return visitor.names | |
1203 | ||
1204 | # Validates that all the repetition expressions within `group` don't | |
1205 | # refer, directly or indirectly, to subsequent labels. | |
71aaa3f7 | 1206 | # |
2adf4336 PP |
1207 | # The strategy here is to keep a set of allowed label names, per |
1208 | # group, initialized to `allowed_label_names`, and a set of allowed | |
1209 | # variable names initialized to `allowed_variable_names`. | |
1210 | # | |
1211 | # Then, depending on the type of `item`: | |
1212 | # | |
1213 | # `_Label`: | |
1214 | # Add its name to the local allowed label names: a label | |
1215 | # occurring before a repetition, and not within a nested group, | |
1216 | # is always reachable. | |
1217 | # | |
1218 | # `_VarAssign`: | |
1219 | # If all the names within its expression are allowed, then add | |
1220 | # its name to the allowed variable names. | |
1221 | # | |
1222 | # Otherwise, remove its name from the allowed variable names (if | |
1223 | # it's in there): a variable which refers to an unreachable name | |
1224 | # is unreachable itself. | |
1225 | # | |
1226 | # `_Rep`: | |
1227 | # Make sure all the names within its expression are allowed. | |
1228 | # | |
1229 | # `_Group`: | |
1230 | # Call this function for each contained item with a _copy_ of | |
1231 | # the current allowed label names and the same current allowed | |
1232 | # variable names. | |
1233 | @staticmethod | |
1234 | def _validate_rep_exprs( | |
1235 | item: _Item, allowed_variable_names: Set[str], allowed_label_names: Set[str] | |
1236 | ): | |
1237 | if type(item) is _Label: | |
1238 | allowed_label_names.add(item.name) | |
1239 | elif type(item) is _VarAssign: | |
1240 | # Check if this variable name is allowed | |
1241 | allowed = True | |
1242 | ||
1243 | for name in _Gen._names_of_expr(item.expr): | |
1244 | if name not in ( | |
1245 | allowed_label_names | allowed_variable_names | {_icitte_name} | |
1246 | ): | |
1247 | # Not allowed | |
1248 | allowed = False | |
1249 | break | |
1250 | ||
1251 | if allowed: | |
1252 | allowed_variable_names.add(item.name) | |
1253 | elif item.name in allowed_variable_names: | |
1254 | allowed_variable_names.remove(item.name) | |
71aaa3f7 | 1255 | elif type(item) is _Rep: |
2adf4336 PP |
1256 | # Validate the expression first |
1257 | _ExprValidator( | |
1258 | item, allowed_label_names | allowed_variable_names, False | |
1259 | ).visit(item.expr) | |
1260 | ||
1261 | # Validate inner item | |
1262 | _Gen._validate_rep_exprs( | |
1263 | item.item, allowed_variable_names, allowed_label_names | |
1264 | ) | |
1265 | elif type(item) is _Group: | |
1266 | # Copy `allowed_label_names` so that this frame cannot | |
1267 | # access the nested label names. | |
1268 | group_allowed_label_names = allowed_label_names.copy() | |
71aaa3f7 | 1269 | |
2adf4336 PP |
1270 | for subitem in item.items: |
1271 | _Gen._validate_rep_exprs( | |
1272 | subitem, allowed_variable_names, group_allowed_label_names | |
1273 | ) | |
71aaa3f7 | 1274 | |
2adf4336 PP |
1275 | # Evaluates the expression of `item` considering the current |
1276 | # generation state `state`. | |
1277 | # | |
1278 | # If `allow_icitte` is `True`, then the `ICITTE` name is available | |
1279 | # for the expression to evaluate. | |
1280 | @staticmethod | |
1281 | def _eval_item_expr(item: _ExprItemT, state: _GenState, allow_icitte: bool): | |
1282 | syms = state.labels.copy() | |
71aaa3f7 | 1283 | |
2adf4336 PP |
1284 | # Set the `ICITTE` name to the current offset, if any |
1285 | if allow_icitte: | |
1286 | syms[_icitte_name] = state.offset | |
71aaa3f7 PP |
1287 | |
1288 | # Add the current variables | |
2adf4336 | 1289 | syms.update(state.variables) |
71aaa3f7 PP |
1290 | |
1291 | # Validate the node and its children | |
2adf4336 | 1292 | _ExprValidator(item, set(syms.keys()), True).visit(item.expr) |
71aaa3f7 PP |
1293 | |
1294 | # Compile and evaluate expression node | |
1295 | try: | |
1296 | val = eval(compile(item.expr, "", "eval"), None, syms) | |
1297 | except Exception as exc: | |
1298 | _raise_error_for_item( | |
1299 | "Failed to evaluate expression `{}`: {}".format(item.expr_str, exc), | |
1300 | item, | |
1301 | ) | |
1302 | ||
1303 | # Validate result | |
1304 | if type(val) is not int: | |
1305 | _raise_error_for_item( | |
2adf4336 | 1306 | "Invalid expression `{}`: expecting result type `int`, not `{}`".format( |
71aaa3f7 PP |
1307 | item.expr_str, type(val).__name__ |
1308 | ), | |
1309 | item, | |
1310 | ) | |
1311 | ||
1312 | return val | |
1313 | ||
2adf4336 PP |
1314 | # Computes the effective value (multiplier) for each repetition |
1315 | # instance, filling `instance_vals` (if not `None`) and returning | |
1316 | # `instance_vals`. | |
1317 | # | |
1318 | # At this point it must be known that, for a given repetition, its | |
1319 | # expression only contains reachable names. | |
1320 | # | |
1321 | # When handling a `_Rep` item, this function appends its effective | |
1322 | # multiplier to `instance_vals` _before_ handling its repeated item. | |
1323 | # | |
1324 | # When handling a `_VarAssign` item, this function only evaluates it if | |
1325 | # all its names are reachable. | |
1326 | @staticmethod | |
1327 | def _compute_rep_instance_vals( | |
1328 | item: _Item, state: _GenState, instance_vals: Optional[List[int]] = None | |
1329 | ): | |
1330 | if instance_vals is None: | |
1331 | instance_vals = [] | |
1332 | ||
1333 | if isinstance(item, _ScalarItem): | |
1334 | state.offset += item.size | |
1335 | elif type(item) is _Label: | |
1336 | state.labels[item.name] = state.offset | |
1337 | elif type(item) is _VarAssign: | |
1338 | # Check if all the names are reachable | |
1339 | do_eval = True | |
1340 | ||
1341 | for name in _Gen._names_of_expr(item.expr): | |
1342 | if ( | |
1343 | name != _icitte_name | |
1344 | and name not in state.variables | |
1345 | and name not in state.labels | |
1346 | ): | |
1347 | # A name is unknown: cannot evaluate | |
1348 | do_eval = False | |
1349 | break | |
1350 | ||
1351 | if do_eval: | |
1352 | # Evaluate the expression and keep the result | |
1353 | state.variables[item.name] = _Gen._eval_item_expr(item, state, True) | |
1354 | elif type(item) is _SetOffset: | |
1355 | state.offset = item.val | |
1356 | elif type(item) is _Rep: | |
1357 | # Evaluate the expression and keep the result | |
1358 | val = _Gen._eval_item_expr(item, state, False) | |
1359 | ||
1360 | # Validate result | |
1361 | if val < 0: | |
1362 | _raise_error_for_item( | |
1363 | "Invalid expression `{}`: unexpected negative result {:,}".format( | |
1364 | item.expr_str, val | |
1365 | ), | |
1366 | item, | |
1367 | ) | |
1368 | ||
1369 | # Add to repetition instance values | |
1370 | instance_vals.append(val) | |
1371 | ||
1372 | # Process the repeated item `val` times | |
1373 | for _ in range(val): | |
1374 | _Gen._compute_rep_instance_vals(item.item, state, instance_vals) | |
1375 | elif type(item) is _Group: | |
1376 | prev_labels = state.labels.copy() | |
1377 | ||
1378 | # Process each item | |
1379 | for subitem in item.items: | |
1380 | _Gen._compute_rep_instance_vals(subitem, state, instance_vals) | |
1381 | ||
1382 | state.labels = prev_labels | |
1383 | ||
1384 | return instance_vals | |
1385 | ||
1386 | def _zero_item_size(self, item: _Item, next_rep_instance: int): | |
1387 | return 0, next_rep_instance | |
1388 | ||
1389 | def _scalar_item_size(self, item: _ScalarItem, next_rep_instance: int): | |
1390 | return item.size, next_rep_instance | |
1391 | ||
1392 | def _group_item_size(self, item: _Group, next_rep_instance: int): | |
1393 | size = 0 | |
1394 | ||
1395 | for subitem in item.items: | |
1396 | subitem_size, next_rep_instance = self._item_size( | |
1397 | subitem, next_rep_instance | |
1398 | ) | |
1399 | size += subitem_size | |
1400 | ||
1401 | return size, next_rep_instance | |
1402 | ||
1403 | def _rep_item_size(self, item: _Rep, next_rep_instance: int): | |
1404 | # Get the value from `self._rep_instance_vals` _before_ | |
1405 | # incrementing `next_rep_instance` to honor the order of | |
1406 | # _compute_rep_instance_vals(). | |
1407 | mul = self._rep_instance_vals[next_rep_instance] | |
1408 | next_rep_instance += 1 | |
1409 | size = 0 | |
1410 | ||
1411 | for _ in range(mul): | |
1412 | iter_size, next_rep_instance = self._item_size(item.item, next_rep_instance) | |
1413 | size += iter_size | |
1414 | ||
1415 | return size, next_rep_instance | |
1416 | ||
1417 | # Returns the size of `item` and the new next repetition instance. | |
1418 | def _item_size(self, item: _Item, next_rep_instance: int): | |
1419 | return self._item_size_funcs[type(item)](item, next_rep_instance) | |
1420 | ||
1421 | # Handles the byte item `item`. | |
1422 | def _handle_byte_item(self, item: _Byte, state: _GenState, next_rep_instance: int): | |
1423 | self._data.append(item.val) | |
1424 | state.offset += item.size | |
1425 | return next_rep_instance | |
1426 | ||
1427 | # Handles the string item `item`. | |
1428 | def _handle_str_item(self, item: _Str, state: _GenState, next_rep_instance: int): | |
1429 | self._data += item.data | |
1430 | state.offset += item.size | |
1431 | return next_rep_instance | |
1432 | ||
1433 | # Handles the byte order setting item `item`. | |
1434 | def _handle_set_bo_item( | |
1435 | self, item: _SetBo, state: _GenState, next_rep_instance: int | |
1436 | ): | |
1437 | # Update current byte order | |
1438 | state.bo = item.bo | |
1439 | return next_rep_instance | |
1440 | ||
1441 | # Handles the variable assignment item `item`. | |
1442 | def _handle_var_assign_item( | |
1443 | self, item: _VarAssign, state: _GenState, next_rep_instance: int | |
1444 | ): | |
71aaa3f7 | 1445 | # Update variable |
2adf4336 PP |
1446 | state.variables[item.name] = self._eval_item_expr(item, state, True) |
1447 | return next_rep_instance | |
71aaa3f7 | 1448 | |
2adf4336 PP |
1449 | # Handles the value item `item`. |
1450 | def _handle_val_item(self, item: _Val, state: _GenState, next_rep_instance: int): | |
71aaa3f7 | 1451 | # Compute value |
2adf4336 | 1452 | val = self._eval_item_expr(item, state, True) |
71aaa3f7 PP |
1453 | |
1454 | # Validate range | |
1455 | if val < -(2 ** (item.len - 1)) or val > 2**item.len - 1: | |
1456 | _raise_error_for_item( | |
1457 | "Value {:,} is outside the {}-bit range when evaluating expression `{}` at byte offset {:,}".format( | |
2adf4336 | 1458 | val, item.len, item.expr_str, state.offset |
71aaa3f7 PP |
1459 | ), |
1460 | item, | |
1461 | ) | |
1462 | ||
1463 | # Encode result on 64 bits (to extend the sign bit whatever the | |
1464 | # value of `item.len`). | |
2adf4336 | 1465 | if state.bo is None and item.len > 8: |
71aaa3f7 PP |
1466 | _raise_error_for_item( |
1467 | "Current byte order isn't defined at first value (`{}`) to encode on more than 8 bits".format( | |
1468 | item.expr_str | |
1469 | ), | |
1470 | item, | |
1471 | ) | |
1472 | ||
1473 | data = struct.pack( | |
1474 | "{}{}".format( | |
2adf4336 | 1475 | ">" if state.bo in (None, ByteOrder.BE) else "<", |
71aaa3f7 PP |
1476 | "Q" if val >= 0 else "q", |
1477 | ), | |
1478 | val, | |
1479 | ) | |
1480 | ||
1481 | # Keep only the requested length | |
1482 | len_bytes = item.len // 8 | |
1483 | ||
2adf4336 | 1484 | if state.bo in (None, ByteOrder.BE): |
71aaa3f7 PP |
1485 | # Big endian: keep last bytes |
1486 | data = data[-len_bytes:] | |
1487 | else: | |
1488 | # Little endian: keep first bytes | |
2adf4336 | 1489 | assert state.bo == ByteOrder.LE |
71aaa3f7 PP |
1490 | data = data[:len_bytes] |
1491 | ||
1492 | # Append to current bytes and update offset | |
1493 | self._data += data | |
2adf4336 PP |
1494 | state.offset += len(data) |
1495 | return next_rep_instance | |
71aaa3f7 | 1496 | |
2adf4336 PP |
1497 | # Handles the group item `item`, only removing the immediate labels |
1498 | # from `state.labels` if `remove_immediate_labels` is `True`. | |
1499 | def _handle_group_item( | |
1500 | self, | |
1501 | item: _Group, | |
1502 | state: _GenState, | |
1503 | next_rep_instance: int, | |
1504 | remove_immediate_labels: bool = True, | |
1505 | ): | |
1506 | # Compute the values of the immediate (not nested) labels. Those | |
1507 | # labels are reachable by any expression within the group. | |
1508 | offset = state.offset | |
1509 | immediate_label_names = set() # type: Set[str] | |
1510 | tmp_next_rep_instance = next_rep_instance | |
71aaa3f7 | 1511 | |
2adf4336 PP |
1512 | for subitem in item.items: |
1513 | if type(subitem) is _SetOffset: | |
1514 | # Update offset | |
1515 | offset = subitem.val | |
1516 | elif type(subitem) is _Label: | |
1517 | # New immediate label | |
1518 | state.labels[subitem.name] = offset | |
1519 | immediate_label_names.add(subitem.name) | |
1520 | ||
1521 | subitem_size, tmp_next_rep_instance = self._item_size( | |
1522 | subitem, tmp_next_rep_instance | |
1523 | ) | |
1524 | offset += subitem_size | |
71aaa3f7 | 1525 | |
2adf4336 | 1526 | # Handle each item now with the actual state |
71aaa3f7 | 1527 | for subitem in item.items: |
2adf4336 PP |
1528 | next_rep_instance = self._handle_item(subitem, state, next_rep_instance) |
1529 | ||
1530 | # Remove immediate labels if required so that outer items won't | |
1531 | # reach inner labels. | |
1532 | if remove_immediate_labels: | |
1533 | for name in immediate_label_names: | |
1534 | del state.labels[name] | |
71aaa3f7 | 1535 | |
2adf4336 | 1536 | return next_rep_instance |
71aaa3f7 | 1537 | |
2adf4336 PP |
1538 | # Handles the repetition item `item`. |
1539 | def _handle_rep_item(self, item: _Rep, state: _GenState, next_rep_instance: int): | |
1540 | mul = self._rep_instance_vals[next_rep_instance] | |
1541 | next_rep_instance += 1 | |
71aaa3f7 | 1542 | |
2adf4336 PP |
1543 | for _ in range(mul): |
1544 | next_rep_instance = self._handle_item(item.item, state, next_rep_instance) | |
71aaa3f7 | 1545 | |
2adf4336 | 1546 | return next_rep_instance |
71aaa3f7 | 1547 | |
2adf4336 PP |
1548 | # Handles the offset setting item `item`. |
1549 | def _handle_set_offset_item( | |
1550 | self, item: _SetOffset, state: _GenState, next_rep_instance: int | |
1551 | ): | |
1552 | state.offset = item.val | |
1553 | return next_rep_instance | |
1554 | ||
1555 | # Handles the label item `item`. | |
1556 | def _handle_label_item( | |
1557 | self, item: _Label, state: _GenState, next_rep_instance: int | |
1558 | ): | |
1559 | return next_rep_instance | |
1560 | ||
1561 | # Handles the item `item`, returning the updated next repetition | |
1562 | # instance. | |
1563 | def _handle_item(self, item: _Item, state: _GenState, next_rep_instance: int): | |
1564 | return self._item_handlers[type(item)](item, state, next_rep_instance) | |
1565 | ||
1566 | # Generates the data (`self._data`) and final state | |
1567 | # (`self._final_state`) from `group` and the initial state `state`. | |
1568 | def _gen(self, group: _Group, state: _GenState): | |
71aaa3f7 PP |
1569 | # Initial state |
1570 | self._data = bytearray() | |
71aaa3f7 PP |
1571 | |
1572 | # Item handlers | |
1573 | self._item_handlers = { | |
1574 | _Byte: self._handle_byte_item, | |
71aaa3f7 | 1575 | _Group: self._handle_group_item, |
2adf4336 | 1576 | _Label: self._handle_label_item, |
71aaa3f7 | 1577 | _Rep: self._handle_rep_item, |
2adf4336 PP |
1578 | _SetBo: self._handle_set_bo_item, |
1579 | _SetOffset: self._handle_set_offset_item, | |
1580 | _Str: self._handle_str_item, | |
1581 | _Val: self._handle_val_item, | |
1582 | _VarAssign: self._handle_var_assign_item, | |
1583 | } # type: Dict[type, Callable[[Any, _GenState, int], int]] | |
1584 | ||
1585 | # Item size getters | |
1586 | self._item_size_funcs = { | |
1587 | _Byte: self._scalar_item_size, | |
1588 | _Group: self._group_item_size, | |
1589 | _Label: self._zero_item_size, | |
1590 | _Rep: self._rep_item_size, | |
1591 | _SetBo: self._zero_item_size, | |
1592 | _SetOffset: self._zero_item_size, | |
1593 | _Str: self._scalar_item_size, | |
1594 | _Val: self._scalar_item_size, | |
1595 | _VarAssign: self._zero_item_size, | |
1596 | } # type: Dict[type, Callable[[Any, int], Tuple[int, int]]] | |
1597 | ||
1598 | # Handle the group item, _not_ removing the immediate labels | |
1599 | # because the `labels` property offers them. | |
1600 | self._handle_group_item(group, state, 0, False) | |
1601 | ||
1602 | # This is actually the final state | |
1603 | self._final_state = state | |
71aaa3f7 PP |
1604 | |
1605 | ||
1606 | # Returns a `ParseResult` instance containing the bytes encoded by the | |
1607 | # input string `normand`. | |
1608 | # | |
1609 | # `init_variables` is a dictionary of initial variable names (valid | |
1610 | # Python names) to integral values. A variable name must not be the | |
1611 | # reserved name `ICITTE`. | |
1612 | # | |
1613 | # `init_labels` is a dictionary of initial label names (valid Python | |
1614 | # names) to integral values. A label name must not be the reserved name | |
1615 | # `ICITTE`. | |
1616 | # | |
1617 | # `init_offset` is the initial offset. | |
1618 | # | |
1619 | # `init_byte_order` is the initial byte order. | |
1620 | # | |
1621 | # Raises `ParseError` on any parsing error. | |
1622 | def parse( | |
1623 | normand: str, | |
1624 | init_variables: Optional[VarsT] = None, | |
1625 | init_labels: Optional[VarsT] = None, | |
1626 | init_offset: int = 0, | |
1627 | init_byte_order: Optional[ByteOrder] = None, | |
1628 | ): | |
1629 | if init_variables is None: | |
1630 | init_variables = {} | |
1631 | ||
1632 | if init_labels is None: | |
1633 | init_labels = {} | |
1634 | ||
1635 | gen = _Gen( | |
1636 | _Parser(normand, init_variables, init_labels).res, | |
1637 | init_variables, | |
1638 | init_labels, | |
1639 | init_offset, | |
1640 | init_byte_order, | |
1641 | ) | |
1642 | return ParseResult._create( # pyright: ignore[reportPrivateUsage] | |
1643 | gen.data, gen.variables, gen.labels, gen.offset, gen.bo | |
1644 | ) | |
1645 | ||
1646 | ||
1647 | # Parses the command-line arguments. | |
1648 | def _parse_cli_args(): | |
1649 | import argparse | |
1650 | ||
1651 | # Build parser | |
1652 | ap = argparse.ArgumentParser() | |
1653 | ap.add_argument( | |
1654 | "--offset", | |
1655 | metavar="OFFSET", | |
1656 | action="store", | |
1657 | type=int, | |
1658 | default=0, | |
1659 | help="initial offset (positive)", | |
1660 | ) | |
1661 | ap.add_argument( | |
1662 | "-b", | |
1663 | "--byte-order", | |
1664 | metavar="BO", | |
1665 | choices=["be", "le"], | |
1666 | type=str, | |
1667 | help="initial byte order (`be` or `le`)", | |
1668 | ) | |
1669 | ap.add_argument( | |
1670 | "--var", | |
1671 | metavar="NAME=VAL", | |
1672 | action="append", | |
1673 | help="add an initial variable (may be repeated)", | |
1674 | ) | |
1675 | ap.add_argument( | |
1676 | "-l", | |
1677 | "--label", | |
1678 | metavar="NAME=VAL", | |
1679 | action="append", | |
1680 | help="add an initial label (may be repeated)", | |
1681 | ) | |
1682 | ap.add_argument( | |
1683 | "--version", action="version", version="Normand {}".format(__version__) | |
1684 | ) | |
1685 | ap.add_argument( | |
1686 | "path", | |
1687 | metavar="PATH", | |
1688 | action="store", | |
1689 | nargs="?", | |
1690 | help="input path (none means standard input)", | |
1691 | ) | |
1692 | ||
1693 | # Parse | |
1694 | return ap.parse_args() | |
1695 | ||
1696 | ||
1697 | # Raises a command-line error with the message `msg`. | |
1698 | def _raise_cli_error(msg: str) -> NoReturn: | |
1699 | raise RuntimeError("Command-line error: {}".format(msg)) | |
1700 | ||
1701 | ||
1702 | # Returns a dictionary of string to integers from the list of strings | |
1703 | # `args` containing `NAME=VAL` entries. | |
1704 | def _dict_from_arg(args: Optional[List[str]]): | |
1705 | d = {} # type: Dict[str, int] | |
1706 | ||
1707 | if args is None: | |
1708 | return d | |
1709 | ||
1710 | for arg in args: | |
1711 | m = re.match(r"({})=(\d+)$".format(_py_name_pat.pattern), arg) | |
1712 | ||
1713 | if m is None: | |
1714 | _raise_cli_error("Invalid assignment {}".format(arg)) | |
1715 | ||
2e1c1acd PP |
1716 | d[m.group(1)] = int(m.group(2)) |
1717 | ||
71aaa3f7 PP |
1718 | return d |
1719 | ||
1720 | ||
1721 | # CLI entry point without exception handling. | |
1722 | def _try_run_cli(): | |
1723 | import os.path | |
1724 | ||
1725 | # Parse arguments | |
1726 | args = _parse_cli_args() | |
1727 | ||
1728 | # Read input | |
1729 | if args.path is None: | |
1730 | normand = sys.stdin.read() | |
1731 | else: | |
1732 | with open(args.path) as f: | |
1733 | normand = f.read() | |
1734 | ||
1735 | # Variables and labels | |
1736 | variables = _dict_from_arg(args.var) | |
1737 | labels = _dict_from_arg(args.label) | |
1738 | ||
1739 | # Validate offset | |
1740 | if args.offset < 0: | |
1741 | _raise_cli_error("Invalid negative offset {}") | |
1742 | ||
1743 | # Validate and set byte order | |
1744 | bo = None # type: Optional[ByteOrder] | |
1745 | ||
1746 | if args.byte_order is not None: | |
1747 | if args.byte_order == "be": | |
1748 | bo = ByteOrder.BE | |
1749 | else: | |
1750 | assert args.byte_order == "le" | |
1751 | bo = ByteOrder.LE | |
1752 | ||
1753 | # Parse | |
1754 | try: | |
1755 | res = parse(normand, variables, labels, args.offset, bo) | |
1756 | except ParseError as exc: | |
1757 | prefix = "" | |
1758 | ||
1759 | if args.path is not None: | |
1760 | prefix = "{}:".format(os.path.abspath(args.path)) | |
1761 | ||
1762 | _fail( | |
1763 | "{}{}:{} - {}".format( | |
1764 | prefix, exc.text_loc.line_no, exc.text_loc.col_no, str(exc) | |
1765 | ) | |
1766 | ) | |
1767 | ||
1768 | ||
1769 | sys.stdout.buffer.write(res.data) | |
1770 | ||
1771 | ||
1772 | # Prints the exception message `msg` and exits with status 1. | |
1773 | def _fail(msg: str) -> NoReturn: | |
1774 | if not msg.endswith("."): | |
1775 | msg += "." | |
1776 | ||
1777 | print(msg, file=sys.stderr) | |
1778 | sys.exit(1) | |
1779 | ||
1780 | ||
1781 | # CLI entry point. | |
1782 | def _run_cli(): | |
1783 | try: | |
1784 | _try_run_cli() | |
1785 | except Exception as exc: | |
1786 | _fail(str(exc)) | |
1787 | ||
1788 | ||
1789 | if __name__ == "__main__": | |
1790 | _run_cli() |