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1 """ Python 'hex_codec' Codec - 2-digit hex content transfer encoding |
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2 |
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3 Unlike most of the other codecs which target Unicode, this codec |
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4 will return Python string objects for both encode and decode. |
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5 |
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6 Written by Marc-Andre Lemburg (mal@lemburg.com). |
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7 |
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8 """ |
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9 import codecs, binascii |
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10 |
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11 ### Codec APIs |
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12 |
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13 def hex_encode(input,errors='strict'): |
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14 |
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15 """ Encodes the object input and returns a tuple (output |
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16 object, length consumed). |
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17 |
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18 errors defines the error handling to apply. It defaults to |
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19 'strict' handling which is the only currently supported |
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20 error handling for this codec. |
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21 |
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22 """ |
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23 assert errors == 'strict' |
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24 output = binascii.b2a_hex(input) |
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25 return (output, len(input)) |
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26 |
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27 def hex_decode(input,errors='strict'): |
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28 |
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29 """ Decodes the object input and returns a tuple (output |
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30 object, length consumed). |
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31 |
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32 input must be an object which provides the bf_getreadbuf |
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33 buffer slot. Python strings, buffer objects and memory |
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34 mapped files are examples of objects providing this slot. |
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35 |
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36 errors defines the error handling to apply. It defaults to |
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37 'strict' handling which is the only currently supported |
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38 error handling for this codec. |
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39 |
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40 """ |
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41 assert errors == 'strict' |
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42 output = binascii.a2b_hex(input) |
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43 return (output, len(input)) |
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44 |
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45 class Codec(codecs.Codec): |
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46 |
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47 def encode(self, input,errors='strict'): |
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48 return hex_encode(input,errors) |
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49 def decode(self, input,errors='strict'): |
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50 return hex_decode(input,errors) |
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51 |
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52 class IncrementalEncoder(codecs.IncrementalEncoder): |
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53 def encode(self, input, final=False): |
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54 assert self.errors == 'strict' |
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55 return binascii.b2a_hex(input) |
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56 |
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57 class IncrementalDecoder(codecs.IncrementalDecoder): |
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58 def decode(self, input, final=False): |
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59 assert self.errors == 'strict' |
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60 return binascii.a2b_hex(input) |
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61 |
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62 class StreamWriter(Codec,codecs.StreamWriter): |
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63 pass |
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64 |
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65 class StreamReader(Codec,codecs.StreamReader): |
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66 pass |
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67 |
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68 ### encodings module API |
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69 |
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70 def getregentry(): |
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71 return codecs.CodecInfo( |
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72 name='hex', |
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73 encode=hex_encode, |
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74 decode=hex_decode, |
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75 incrementalencoder=IncrementalEncoder, |
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76 incrementaldecoder=IncrementalDecoder, |
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77 streamwriter=StreamWriter, |
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78 streamreader=StreamReader, |
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79 ) |