1""" 2User name to file name conversion. 3This was taken form the UFO 3 spec. 4""" 5from __future__ import absolute_import, unicode_literals 6from fontTools.misc.py23 import basestring, unicode 7 8 9illegalCharacters = "\" * + / : < > ? [ \ ] | \0".split(" ") 10illegalCharacters += [chr(i) for i in range(1, 32)] 11illegalCharacters += [chr(0x7F)] 12reservedFileNames = "CON PRN AUX CLOCK$ NUL A:-Z: COM1".lower().split(" ") 13reservedFileNames += "LPT1 LPT2 LPT3 COM2 COM3 COM4".lower().split(" ") 14maxFileNameLength = 255 15 16 17class NameTranslationError(Exception): 18 pass 19 20 21def userNameToFileName(userName, existing=[], prefix="", suffix=""): 22 """ 23 existing should be a case-insensitive list 24 of all existing file names. 25 26 >>> userNameToFileName("a") == "a" 27 True 28 >>> userNameToFileName("A") == "A_" 29 True 30 >>> userNameToFileName("AE") == "A_E_" 31 True 32 >>> userNameToFileName("Ae") == "A_e" 33 True 34 >>> userNameToFileName("ae") == "ae" 35 True 36 >>> userNameToFileName("aE") == "aE_" 37 True 38 >>> userNameToFileName("a.alt") == "a.alt" 39 True 40 >>> userNameToFileName("A.alt") == "A_.alt" 41 True 42 >>> userNameToFileName("A.Alt") == "A_.A_lt" 43 True 44 >>> userNameToFileName("A.aLt") == "A_.aL_t" 45 True 46 >>> userNameToFileName(u"A.alT") == "A_.alT_" 47 True 48 >>> userNameToFileName("T_H") == "T__H_" 49 True 50 >>> userNameToFileName("T_h") == "T__h" 51 True 52 >>> userNameToFileName("t_h") == "t_h" 53 True 54 >>> userNameToFileName("F_F_I") == "F__F__I_" 55 True 56 >>> userNameToFileName("f_f_i") == "f_f_i" 57 True 58 >>> userNameToFileName("Aacute_V.swash") == "A_acute_V_.swash" 59 True 60 >>> userNameToFileName(".notdef") == "_notdef" 61 True 62 >>> userNameToFileName("con") == "_con" 63 True 64 >>> userNameToFileName("CON") == "C_O_N_" 65 True 66 >>> userNameToFileName("con.alt") == "_con.alt" 67 True 68 >>> userNameToFileName("alt.con") == "alt._con" 69 True 70 """ 71 # the incoming name must be a unicode string 72 if not isinstance(userName, unicode): 73 raise ValueError("The value for userName must be a unicode string.") 74 # establish the prefix and suffix lengths 75 prefixLength = len(prefix) 76 suffixLength = len(suffix) 77 # replace an initial period with an _ 78 # if no prefix is to be added 79 if not prefix and userName[0] == ".": 80 userName = "_" + userName[1:] 81 # filter the user name 82 filteredUserName = [] 83 for character in userName: 84 # replace illegal characters with _ 85 if character in illegalCharacters: 86 character = "_" 87 # add _ to all non-lower characters 88 elif character != character.lower(): 89 character += "_" 90 filteredUserName.append(character) 91 userName = "".join(filteredUserName) 92 # clip to 255 93 sliceLength = maxFileNameLength - prefixLength - suffixLength 94 userName = userName[:sliceLength] 95 # test for illegal files names 96 parts = [] 97 for part in userName.split("."): 98 if part.lower() in reservedFileNames: 99 part = "_" + part 100 parts.append(part) 101 userName = ".".join(parts) 102 # test for clash 103 fullName = prefix + userName + suffix 104 if fullName.lower() in existing: 105 fullName = handleClash1(userName, existing, prefix, suffix) 106 # finished 107 return fullName 108 109def handleClash1(userName, existing=[], prefix="", suffix=""): 110 """ 111 existing should be a case-insensitive list 112 of all existing file names. 113 114 >>> prefix = ("0" * 5) + "." 115 >>> suffix = "." + ("0" * 10) 116 >>> existing = ["a" * 5] 117 118 >>> e = list(existing) 119 >>> handleClash1(userName="A" * 5, existing=e, 120 ... prefix=prefix, suffix=suffix) == ( 121 ... '00000.AAAAA000000000000001.0000000000') 122 True 123 124 >>> e = list(existing) 125 >>> e.append(prefix + "aaaaa" + "1".zfill(15) + suffix) 126 >>> handleClash1(userName="A" * 5, existing=e, 127 ... prefix=prefix, suffix=suffix) == ( 128 ... '00000.AAAAA000000000000002.0000000000') 129 True 130 131 >>> e = list(existing) 132 >>> e.append(prefix + "AAAAA" + "2".zfill(15) + suffix) 133 >>> handleClash1(userName="A" * 5, existing=e, 134 ... prefix=prefix, suffix=suffix) == ( 135 ... '00000.AAAAA000000000000001.0000000000') 136 True 137 """ 138 # if the prefix length + user name length + suffix length + 15 is at 139 # or past the maximum length, silce 15 characters off of the user name 140 prefixLength = len(prefix) 141 suffixLength = len(suffix) 142 if prefixLength + len(userName) + suffixLength + 15 > maxFileNameLength: 143 l = (prefixLength + len(userName) + suffixLength + 15) 144 sliceLength = maxFileNameLength - l 145 userName = userName[:sliceLength] 146 finalName = None 147 # try to add numbers to create a unique name 148 counter = 1 149 while finalName is None: 150 name = userName + str(counter).zfill(15) 151 fullName = prefix + name + suffix 152 if fullName.lower() not in existing: 153 finalName = fullName 154 break 155 else: 156 counter += 1 157 if counter >= 999999999999999: 158 break 159 # if there is a clash, go to the next fallback 160 if finalName is None: 161 finalName = handleClash2(existing, prefix, suffix) 162 # finished 163 return finalName 164 165def handleClash2(existing=[], prefix="", suffix=""): 166 """ 167 existing should be a case-insensitive list 168 of all existing file names. 169 170 >>> prefix = ("0" * 5) + "." 171 >>> suffix = "." + ("0" * 10) 172 >>> existing = [prefix + str(i) + suffix for i in range(100)] 173 174 >>> e = list(existing) 175 >>> handleClash2(existing=e, prefix=prefix, suffix=suffix) == ( 176 ... '00000.100.0000000000') 177 True 178 179 >>> e = list(existing) 180 >>> e.remove(prefix + "1" + suffix) 181 >>> handleClash2(existing=e, prefix=prefix, suffix=suffix) == ( 182 ... '00000.1.0000000000') 183 True 184 185 >>> e = list(existing) 186 >>> e.remove(prefix + "2" + suffix) 187 >>> handleClash2(existing=e, prefix=prefix, suffix=suffix) == ( 188 ... '00000.2.0000000000') 189 True 190 """ 191 # calculate the longest possible string 192 maxLength = maxFileNameLength - len(prefix) - len(suffix) 193 maxValue = int("9" * maxLength) 194 # try to find a number 195 finalName = None 196 counter = 1 197 while finalName is None: 198 fullName = prefix + str(counter) + suffix 199 if fullName.lower() not in existing: 200 finalName = fullName 201 break 202 else: 203 counter += 1 204 if counter >= maxValue: 205 break 206 # raise an error if nothing has been found 207 if finalName is None: 208 raise NameTranslationError("No unique name could be found.") 209 # finished 210 return finalName 211 212if __name__ == "__main__": 213 import doctest 214 doctest.testmod() 215