Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.11/site-packages/bitstring/__init__.py: 72%

1#!/usr/bin/env python 

2r""" 

3This package defines classes that simplify bit-wise creation, manipulation and 

4interpretation of data. 

5 

6Classes: 

7 

8Bits -- An immutable container for binary data. 

9BitArray -- A mutable container for binary data. 

10ConstBitStream -- An immutable container with streaming methods. 

11BitStream -- A mutable container with streaming methods. 

12Array -- An efficient list-like container where each item has a fixed-length binary format. 

13Dtype -- Encapsulate the data types used in the other classes. 

14 

15Functions: 

16 

17pack -- Create a BitStream from a format string. 

18 

19Data: 

20 

21options -- Module-wide options. 

22 

23Exceptions: 

24 

25Error -- Module exception base class. 

26CreationError -- Error during creation. 

27InterpretError -- Inappropriate interpretation of binary data. 

28ByteAlignError -- Whole byte position or length needed. 

29ReadError -- Reading or peeking past the end of a bitstring. 

30 

31https://github.com/scott-griffiths/bitstring 

32""" 

33 

34__licence__ = """ 

35The MIT License 

36 

37Copyright (c) 2006 Scott Griffiths (dr.scottgriffiths@gmail.com) 

38 

39Permission is hereby granted, free of charge, to any person obtaining a copy 

40of this software and associated documentation files (the "Software"), to deal 

41in the Software without restriction, including without limitation the rights 

42to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 

43copies of the Software, and to permit persons to whom the Software is 

44furnished to do so, subject to the following conditions: 

45 

46The above copyright notice and this permission notice shall be included in 

47all copies or substantial portions of the Software. 

48 

49THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 

50IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 

51FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 

52AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 

53LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 

54OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 

55THE SOFTWARE. 

56""" 

57 

58__version__ = "4.4.0" 

59 

60__author__ = "Scott Griffiths" 

61 

62import sys 

63import os 

64import importlib 

65 

66# New ability to use tibs for core operations instead of bitarray. 

67# Tibs is written in Rust and is still in beta. Use the environment variable 

68# BITSTRING_USE_RUST_CORE=1 before importing the module to turn it on. 

69_env_core = os.getenv('BITSTRING_USE_RUST_CORE', '').strip().lower() 

70_USE_RUST_CORE = _env_core in ('1', 'true', 'yes', 'on') 

71if _USE_RUST_CORE: 

72 bitstore = importlib.import_module('bitstring.bitstore_tibs') 

73 bitstore_helpers = importlib.import_module('bitstring.bitstore_tibs_helpers') 

74else: 

75 bitstore = importlib.import_module('bitstring.bitstore_bitarray') 

76 bitstore_helpers = importlib.import_module('bitstring.bitstore_bitarray_helpers') 

77bitstore_common_helpers = importlib.import_module('bitstring.bitstore_common_helpers') 

78 

79from .bits import Bits 

80from .bitstring_options import Options 

81from .bitarray_ import BitArray 

82from .bitstream import ConstBitStream, BitStream 

83from .methods import pack 

84from .array_ import Array 

85from .exceptions import Error, ReadError, InterpretError, ByteAlignError, CreationError 

86from .dtypes import DtypeDefinition, dtype_register, Dtype 

87import types 

88from typing import List, Tuple, Literal 

89from .mxfp import decompress_luts as mxfp_decompress_luts 

90from .fp8 import decompress_luts as binary8_decompress_luts 

91 

92# Decompress the LUTs for the exotic floating point formats 

93mxfp_decompress_luts() 

94binary8_decompress_luts() 

95 

96# The Options class returns a singleton. 

97options = Options() 

98 

99# These get defined properly by the module magic below. This just stops mypy complaining about them. 

100bytealigned = lsb0 = None 

101 

102 

103# An opaque way of adding module level properties. Taken from https://peps.python.org/pep-0549/ 

104# This is now deprecated. Use the options object directly instead. 

105class _MyModuleType(types.ModuleType): 

106 @property 

107 def bytealigned(self) -> bool: 

108 """Determines whether a number of methods default to working only on byte boundaries.""" 

109 return options.bytealigned 

110 

111 @bytealigned.setter 

112 def bytealigned(self, value: bool) -> None: 

113 """Determines whether a number of methods default to working only on byte boundaries.""" 

114 options.bytealigned = value 

115 

116 @property 

117 def lsb0(self) -> bool: 

118 """If True, the least significant bit (the final bit) is indexed as bit zero.""" 

119 return options.lsb0 

120 

121 @lsb0.setter 

122 def lsb0(self, value: bool) -> None: 

123 """If True, the least significant bit (the final bit) is indexed as bit zero.""" 

124 options.lsb0 = value 

125 

126 

127sys.modules[__name__].__class__ = _MyModuleType 

128 

129 

130# These methods convert a bit length to the number of characters needed to print it for different interpretations. 

131def hex_bits2chars(bitlength: int): 

132 # One character for every 4 bits 

133 return bitlength // 4 

134 

135 

136def oct_bits2chars(bitlength: int): 

137 # One character for every 3 bits 

138 return bitlength // 3 

139 

140 

141def bin_bits2chars(bitlength: int): 

142 # One character for each bit 

143 return bitlength 

144 

145 

146def bytes_bits2chars(bitlength: int): 

147 # One character for every 8 bits 

148 return bitlength // 8 

149 

150 

151def uint_bits2chars(bitlength: int): 

152 # How many characters is largest possible int of this length? 

153 return len(str((1 << bitlength) - 1)) 

154 

155 

156def int_bits2chars(bitlength: int): 

157 # How many characters is largest negative int of this length? (To include minus sign). 

158 return len(str((-1 << (bitlength - 1)))) 

159 

160 

161def float_bits2chars(bitlength: Literal[16, 32, 64]): 

162 # These bit lengths were found by looking at lots of possible values 

163 if bitlength in [16, 32]: 

164 return 23 # Empirical value 

165 else: 

166 return 24 # Empirical value 

167 

168 

169def p3binary_bits2chars(_: Literal[8]): 

170 return 19 # Empirical value 

171 

172 

173def p4binary_bits2chars(_: Literal[8]): 

174 # Found by looking at all the possible values 

175 return 13 # Empirical value 

176 

177 

178def e4m3mxfp_bits2chars(_: Literal[8]): 

179 return 13 

180 

181 

182def e5m2mxfp_bits2chars(_: Literal[8]): 

183 return 19 

184 

185 

186def e3m2mxfp_bits2chars(_: Literal[6]): 

187 # Not sure what the best value is here. It's 7 without considering the scale that could be applied. 

188 return 7 

189 

190 

191def e2m3mxfp_bits2chars(_: Literal[6]): 

192 # Not sure what the best value is here. 

193 return 7 

194 

195 

196def e2m1mxfp_bits2chars(_: Literal[4]): 

197 # Not sure what the best value is here. 

198 return 7 

199 

200 

201def e8m0mxfp_bits2chars(_: Literal[8]): 

202 # Has same range as float32 

203 return 23 

204 

205 

206def mxint_bits2chars(_: Literal[8]): 

207 # Not sure what the best value is here. 

208 return 10 

209 

210 

211def bfloat_bits2chars(_: Literal[16]): 

212 # Found by looking at all the possible values 

213 return 23 # Empirical value 

214 

215 

216def bits_bits2chars(bitlength: int): 

217 # For bits type we can see how long it needs to be printed by trying any value 

218 temp = Bits(bitlength) 

219 return len(str(temp)) 

220 

221 

222def bool_bits2chars(_: Literal[1]): 

223 # Bools are printed as 1 or 0, not True or False, so are one character each 

224 return 1 

225 

226 

227dtype_definitions = [ 

228 # Integer types 

229 DtypeDefinition('uint', Bits._setuint, Bits._getuint, int, False, uint_bits2chars, 

230 description="a two's complement unsigned int"), 

231 DtypeDefinition('uintle', Bits._setuintle, Bits._getuintle, int, False, uint_bits2chars, 

232 allowed_lengths=(8, 16, 24, ...), description="a two's complement little-endian unsigned int"), 

233 DtypeDefinition('uintbe', Bits._setuintbe, Bits._getuintbe, int, False, uint_bits2chars, 

234 allowed_lengths=(8, 16, 24, ...), description="a two's complement big-endian unsigned int"), 

235 DtypeDefinition('int', Bits._setint, Bits._getint, int, True, int_bits2chars, 

236 description="a two's complement signed int"), 

237 DtypeDefinition('intle', Bits._setintle, Bits._getintle, int, True, int_bits2chars, 

238 allowed_lengths=(8, 16, 24, ...), description="a two's complement little-endian signed int"), 

239 DtypeDefinition('intbe', Bits._setintbe, Bits._getintbe, int, True, int_bits2chars, 

240 allowed_lengths=(8, 16, 24, ...), description="a two's complement big-endian signed int"), 

241 # String types 

242 DtypeDefinition('hex', Bits._sethex, Bits._gethex, str, False, hex_bits2chars, 

243 allowed_lengths=(0, 4, 8, ...), description="a hexadecimal string"), 

244 DtypeDefinition('bin', Bits._setbin, Bits._getbin, str, False, bin_bits2chars, 

245 description="a binary string"), 

246 DtypeDefinition('oct', Bits._setoct, Bits._getoct, str, False, oct_bits2chars, 

247 allowed_lengths=(0, 3, 6, ...), description="an octal string"), 

248 # Float types 

249 DtypeDefinition('float', Bits._setfloatbe, Bits._getfloatbe, float, True, float_bits2chars, 

250 allowed_lengths=(16, 32, 64), description="a big-endian floating point number"), 

251 DtypeDefinition('floatle', Bits._setfloatle, Bits._getfloatle, float, True, float_bits2chars, 

252 allowed_lengths=(16, 32, 64), description="a little-endian floating point number"), 

253 DtypeDefinition('bfloat', Bits._setbfloatbe, Bits._getbfloatbe, float, True, bfloat_bits2chars, 

254 allowed_lengths=(16,), description="a 16 bit big-endian bfloat floating point number"), 

255 DtypeDefinition('bfloatle', Bits._setbfloatle, Bits._getbfloatle, float, True, bfloat_bits2chars, 

256 allowed_lengths=(16,), description="a 16 bit little-endian bfloat floating point number"), 

257 # Other known length types 

258 DtypeDefinition('bits', Bits._setbits, Bits._getbits, Bits, False, bits_bits2chars, 

259 description="a bitstring object"), 

260 DtypeDefinition('bool', Bits._setbool, Bits._getbool, bool, False, bool_bits2chars, 

261 allowed_lengths=(1,), description="a bool (True or False)"), 

262 DtypeDefinition('bytes', Bits._setbytes, Bits._getbytes, bytes, False, bytes_bits2chars, 

263 multiplier=8, description="a bytes object"), 

264 # Unknown length types 

265 DtypeDefinition('se', Bits._setse, Bits._getse, int, True, None, 

266 variable_length=True, description="a signed exponential-Golomb code"), 

267 DtypeDefinition('ue', Bits._setue, Bits._getue, int, False, None, 

268 variable_length=True, description="an unsigned exponential-Golomb code"), 

269 DtypeDefinition('sie', Bits._setsie, Bits._getsie, int, True, None, 

270 variable_length=True, description="a signed interleaved exponential-Golomb code"), 

271 DtypeDefinition('uie', Bits._setuie, Bits._getuie, int, False, None, 

272 variable_length=True, description="an unsigned interleaved exponential-Golomb code"), 

273 # Special case pad type 

274 DtypeDefinition('pad', Bits._setpad, Bits._getpad, None, False, None, 

275 description="a skipped section of padding"), 

276 

277 # MXFP and IEEE 8-bit float types 

278 DtypeDefinition('p3binary', Bits._setp3binary, Bits._getp3binary, float, True, p3binary_bits2chars, 

279 allowed_lengths=(8,), description="an 8 bit float with binary8p3 format"), 

280 DtypeDefinition('p4binary', Bits._setp4binary, Bits._getp4binary, float, True, p4binary_bits2chars, 

281 allowed_lengths=(8,), description="an 8 bit float with binary8p4 format"), 

282 DtypeDefinition('e4m3mxfp', Bits._sete4m3mxfp, Bits._gete4m3mxfp, float, True, e4m3mxfp_bits2chars, 

283 allowed_lengths=(8,), description="an 8 bit float with MXFP E4M3 format"), 

284 DtypeDefinition('e5m2mxfp', Bits._sete5m2mxfp, Bits._gete5m2mxfp, float, True, e5m2mxfp_bits2chars, 

285 allowed_lengths=(8,), description="an 8 bit float with MXFP E5M2 format"), 

286 DtypeDefinition('e3m2mxfp', Bits._sete3m2mxfp, Bits._gete3m2mxfp, float, True, e3m2mxfp_bits2chars, 

287 allowed_lengths=(6,), description="a 6 bit float with MXFP E3M2 format"), 

288 DtypeDefinition('e2m3mxfp', Bits._sete2m3mxfp, Bits._gete2m3mxfp, float, True, e2m3mxfp_bits2chars, 

289 allowed_lengths=(6,), description="a 6 bit float with MXFP E2M3 format"), 

290 DtypeDefinition('e2m1mxfp', Bits._sete2m1mxfp, Bits._gete2m1mxfp, float, True, e2m1mxfp_bits2chars, 

291 allowed_lengths=(4,), description="a 4 bit float with MXFP E2M1 format"), 

292 DtypeDefinition('e8m0mxfp', Bits._sete8m0mxfp, Bits._gete8m0mxfp, float, False, e8m0mxfp_bits2chars, 

293 allowed_lengths=(8,), description="an 8 bit float with MXFP E8M0 format"), 

294 DtypeDefinition('mxint', Bits._setmxint, Bits._getmxint, float, True, mxint_bits2chars, 

295 allowed_lengths=(8,), description="an 8 bit float with MXFP INT8 format"), 

296] 

297 

298 

299aliases: List[Tuple[str, str]] = [ 

300 # Floats default to big endian 

301 ('float', 'floatbe'), 

302 ('bfloat', 'bfloatbe'), 

303 

304 # Some single letter aliases for popular types 

305 ('int', 'i'), 

306 ('uint', 'u'), 

307 ('hex', 'h'), 

308 ('oct', 'o'), 

309 ('bin', 'b'), 

310 ('float', 'f'), 

311] 

312 

313# Create native-endian aliases depending on the byteorder of the system 

314byteorder: str = sys.byteorder 

315if byteorder == 'little': 

316 aliases.extend([ 

317 ('uintle', 'uintne'), 

318 ('intle', 'intne'), 

319 ('floatle', 'floatne'), 

320 ('bfloatle', 'bfloatne'), 

321 ]) 

322else: 

323 aliases.extend([ 

324 ('uintbe', 'uintne'), 

325 ('intbe', 'intne'), 

326 ('floatbe', 'floatne'), 

327 ('bfloatbe', 'bfloatne'), 

328 ]) 

329 

330 

331for dt in dtype_definitions: 

332 dtype_register.add_dtype(dt) 

333for alias in aliases: 

334 dtype_register.add_dtype_alias(alias[0], alias[1]) 

335 

336property_docstrings = [f'{name} -- Interpret as {dtype_register[name].description}.' for name in dtype_register.names] 

337property_docstring = '\n '.join(property_docstrings) 

338 

339# We can't be sure the docstrings are present, as it might be compiled without docstrings. 

340if Bits.__doc__ is not None: 

341 Bits.__doc__ = Bits.__doc__.replace('[GENERATED_PROPERTY_DESCRIPTIONS]', property_docstring) 

342if BitArray.__doc__ is not None: 

343 BitArray.__doc__ = BitArray.__doc__.replace('[GENERATED_PROPERTY_DESCRIPTIONS]', property_docstring) 

344if ConstBitStream.__doc__ is not None: 

345 ConstBitStream.__doc__ = ConstBitStream.__doc__.replace('[GENERATED_PROPERTY_DESCRIPTIONS]', property_docstring) 

346if BitStream.__doc__ is not None: 

347 BitStream.__doc__ = BitStream.__doc__.replace('[GENERATED_PROPERTY_DESCRIPTIONS]', property_docstring) 

348 

349 

350__all__ = ['ConstBitStream', 'BitStream', 'BitArray', 'Array', 

351 'Bits', 'pack', 'Error', 'ReadError', 'InterpretError', 

352 'ByteAlignError', 'CreationError', 'bytealigned', 'lsb0', 'Dtype', 'options']