Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.9/dist-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__ = "4.2.1" 

59 

60__author__ = "Scott Griffiths" 

61 

62import sys 

63 

64from .bits import Bits 

65from .bitstring_options import Options 

66from .bitarray_ import BitArray 

67from .bitstream import ConstBitStream, BitStream 

68from .methods import pack 

69from .array_ import Array 

70from .exceptions import Error, ReadError, InterpretError, ByteAlignError, CreationError 

71from .dtypes import DtypeDefinition, dtype_register, Dtype 

72import types 

73from typing import List, Tuple, Literal 

74from .mxfp import decompress_luts as mxfp_decompress_luts 

75from .fp8 import decompress_luts as binary8_decompress_luts 

76 

77# Decompress the LUTs for the exotic floating point formats 

78mxfp_decompress_luts() 

79binary8_decompress_luts() 

80 

81# The Options class returns a singleton. 

82options = Options() 

83 

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

85bytealigned = lsb0 = None 

86 

87 

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

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

90class _MyModuleType(types.ModuleType): 

91 @property 

92 def bytealigned(self) -> bool: 

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

94 return options.bytealigned 

95 

96 @bytealigned.setter 

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

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

99 options.bytealigned = value 

100 

101 @property 

102 def lsb0(self) -> bool: 

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

104 return options.lsb0 

105 

106 @lsb0.setter 

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

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

109 options.lsb0 = value 

110 

111 

112sys.modules[__name__].__class__ = _MyModuleType 

113 

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

115def hex_bits2chars(bitlength: int): 

116 # One character for every 4 bits 

117 return bitlength // 4 

118 

119def oct_bits2chars(bitlength: int): 

120 # One character for every 3 bits 

121 return bitlength // 3 

122 

123def bin_bits2chars(bitlength: int): 

124 # One character for each bit 

125 return bitlength 

126 

127def bytes_bits2chars(bitlength: int): 

128 # One character for every 8 bits 

129 return bitlength // 8 

130 

131def uint_bits2chars(bitlength: int): 

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

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

134 

135def int_bits2chars(bitlength: int): 

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

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

138 

139def float_bits2chars(bitlength: Literal[16, 32, 64]): 

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

141 if bitlength in [16, 32]: 

142 return 23 # Empirical value 

143 else: 

144 return 24 # Empirical value 

145 

146def p3binary_bits2chars(bitlength: Literal[8]): 

147 return 19 # Empirical value 

148 

149def p4binary_bits2chars(bitlength: Literal[8]): 

150 # Found by looking at all the possible values 

151 return 13 # Empirical value 

152 

153def e4m3mxfp_bits2chars(bitlength: Literal[8]): 

154 return 13 

155 

156def e5m2mxfp_bits2chars(bitlength: Literal[8]): 

157 return 19 

158 

159def e3m2mxfp_bits2chars(bitlength: Literal[6]): 

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

161 return 7 

162 

163def e2m3mxfp_bits2chars(bitlength: Literal[6]): 

164 # Not sure what the best value is here. 

165 return 7 

166 

167def e2m1mxfp_bits2chars(bitlength: Literal[4]): 

168 # Not sure what the best value is here. 

169 return 7 

170 

171def e8m0mxfp_bits2chars(bitlength: Literal[8]): 

172 # Can range same as float32 

173 return 23 

174 

175def mxint_bits2chars(bitlength: Literal[8]): 

176 # Not sure what the best value is here. 

177 return 10 

178 

179 

180def bfloat_bits2chars(bitlength: Literal[16]): 

181 # Found by looking at all the possible values 

182 return 23 # Empirical value 

183 

184def bits_bits2chars(bitlength: int): 

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

186 temp = Bits(bitlength) 

187 return len(str(temp)) 

188 

189def bool_bits2chars(bitlength: Literal[1]): 

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

191 return 1 

192 

193dtype_definitions = [ 

194 # Integer types 

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

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

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

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

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

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

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

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

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

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

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

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

207 # String types 

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

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

210 DtypeDefinition('bin', Bits._setbin_safe, Bits._getbin, str, False, bin_bits2chars, 

211 description="a binary string"), 

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

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

214 # Float types 

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

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

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

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

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

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

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

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

223 # Other known length types 

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

225 description="a bitstring object"), 

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

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

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

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

230 # Unknown length types 

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

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

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

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

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

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

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

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

239 # Special case pad type 

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

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

242 

243 # MXFP and IEEE 8-bit float types 

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

262] 

263 

264 

265aliases: List[Tuple[str, str]] = [ 

266 # Floats default to big endian 

267 ('float', 'floatbe'), 

268 ('bfloat', 'bfloatbe'), 

269 

270 # Some single letter aliases for popular types 

271 ('int', 'i'), 

272 ('uint', 'u'), 

273 ('hex', 'h'), 

274 ('oct', 'o'), 

275 ('bin', 'b'), 

276 ('float', 'f'), 

277] 

278 

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

280byteorder: str = sys.byteorder 

281if byteorder == 'little': 

282 aliases.extend([ 

283 ('uintle', 'uintne'), 

284 ('intle', 'intne'), 

285 ('floatle', 'floatne'), 

286 ('bfloatle', 'bfloatne'), 

287 ]) 

288else: 

289 aliases.extend([ 

290 ('uintbe', 'uintne'), 

291 ('intbe', 'intne'), 

292 ('floatbe', 'floatne'), 

293 ('bfloatbe', 'bfloatne'), 

294 ]) 

295 

296 

297for dt in dtype_definitions: 

298 dtype_register.add_dtype(dt) 

299for alias in aliases: 

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

301 

302property_docstrings = [f'{name} -- Interpret as {dtype_register[name].description}.' for name in dtype_register.names] 

303property_docstring = '\n '.join(property_docstrings) 

304 

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

306if Bits.__doc__ is not None: 

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

308if BitArray.__doc__ is not None: 

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

310if ConstBitStream.__doc__ is not None: 

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

312if BitStream.__doc__ is not None: 

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

314 

315 

316__all__ = ['ConstBitStream', 'BitStream', 'BitArray', 'Array', 

317 'Bits', 'pack', 'Error', 'ReadError', 'InterpretError', 

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