Package dbf :: Module tables
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Source Code for Module dbf.tables

   1  "table definitions" 
   2  import os 
   3  import sys 
   4  import csv 
   5  import codecs 
   6  import locale 
   7  import unicodedata 
   8  import weakref 
   9  from array import array 
  10  from decimal import Decimal 
  11  from shutil import copyfileobj 
  12  from dbf import _io as io 
  13  from dbf.dates import Date, DateTime, Time 
  14  from dbf.exceptions import Bof, Eof, DbfError, DataOverflow, FieldMissing, NonUnicode 
  15   
  16  input_decoding = locale.getdefaultlocale()[1]    # treat non-unicode data as ... 
  17  default_codepage = 'cp1252' # if no codepage specified on dbf creation, use this 
  18  return_ascii = True         # convert back to icky ascii, losing chars if no mapping 
  19   
  20  version_map = { 
  21          '\x02' : 'FoxBASE', 
  22          '\x03' : 'dBase III Plus', 
  23          '\x04' : 'dBase IV', 
  24          '\x05' : 'dBase V', 
  25          '\x30' : 'Visual FoxPro', 
  26          '\x31' : 'Visual FoxPro (auto increment field)', 
  27          '\x43' : 'dBase IV SQL', 
  28          '\x7b' : 'dBase IV w/memos', 
  29          '\x83' : 'dBase III Plus w/memos', 
  30          '\x8b' : 'dBase IV w/memos', 
  31          '\x8e' : 'dBase IV w/SQL table', 
  32          '\xf5' : 'FoxPro w/memos'} 
  33   
  34  code_pages = { 
  35          '\x00' : ('ascii', "plain ol' ascii"), 
  36          '\x01' : ('cp437', 'U.S. MS-DOS'), 
  37          '\x02' : ('cp850', 'International MS-DOS'), 
  38          '\x03' : ('cp1252', 'Windows ANSI'), 
  39          '\x04' : ('mac_roman', 'Standard Macintosh'), 
  40          '\x08' : ('cp865', 'Danish OEM'), 
  41          '\x09' : ('cp437', 'Dutch OEM'), 
  42          '\x0A' : ('cp850', 'Dutch OEM (secondary)'), 
  43          '\x0B' : ('cp437', 'Finnish OEM'), 
  44          '\x0D' : ('cp437', 'French OEM'), 
  45          '\x0E' : ('cp850', 'French OEM (secondary)'), 
  46          '\x0F' : ('cp437', 'German OEM'), 
  47          '\x10' : ('cp850', 'German OEM (secondary)'), 
  48          '\x11' : ('cp437', 'Italian OEM'), 
  49          '\x12' : ('cp850', 'Italian OEM (secondary)'), 
  50          '\x13' : ('cp932', 'Japanese Shift-JIS'), 
  51          '\x14' : ('cp850', 'Spanish OEM (secondary)'), 
  52          '\x15' : ('cp437', 'Swedish OEM'), 
  53          '\x16' : ('cp850', 'Swedish OEM (secondary)'), 
  54          '\x17' : ('cp865', 'Norwegian OEM'), 
  55          '\x18' : ('cp437', 'Spanish OEM'), 
  56          '\x19' : ('cp437', 'English OEM (Britain)'), 
  57          '\x1A' : ('cp850', 'English OEM (Britain) (secondary)'), 
  58          '\x1B' : ('cp437', 'English OEM (U.S.)'), 
  59          '\x1C' : ('cp863', 'French OEM (Canada)'), 
  60          '\x1D' : ('cp850', 'French OEM (secondary)'), 
  61          '\x1F' : ('cp852', 'Czech OEM'), 
  62          '\x22' : ('cp852', 'Hungarian OEM'), 
  63          '\x23' : ('cp852', 'Polish OEM'), 
  64          '\x24' : ('cp860', 'Portugese OEM'), 
  65          '\x25' : ('cp850', 'Potugese OEM (secondary)'), 
  66          '\x26' : ('cp866', 'Russian OEM'), 
  67          '\x37' : ('cp850', 'English OEM (U.S.) (secondary)'), 
  68          '\x40' : ('cp852', 'Romanian OEM'), 
  69          '\x4D' : ('cp936', 'Chinese GBK (PRC)'), 
  70          '\x4E' : ('cp949', 'Korean (ANSI/OEM)'), 
  71          '\x4F' : ('cp950', 'Chinese Big 5 (Taiwan)'), 
  72          '\x50' : ('cp874', 'Thai (ANSI/OEM)'), 
  73          '\x57' : ('cp1252', 'ANSI'), 
  74          '\x58' : ('cp1252', 'Western European ANSI'), 
  75          '\x59' : ('cp1252', 'Spanish ANSI'), 
  76          '\x64' : ('cp852', 'Eastern European MS-DOS'), 
  77          '\x65' : ('cp866', 'Russian MS-DOS'), 
  78          '\x66' : ('cp865', 'Nordic MS-DOS'), 
  79          '\x67' : ('cp861', 'Icelandic MS-DOS'), 
  80          '\x68' : (None, 'Kamenicky (Czech) MS-DOS'), 
  81          '\x69' : (None, 'Mazovia (Polish) MS-DOS'), 
  82          '\x6a' : ('cp737', 'Greek MS-DOS (437G)'), 
  83          '\x6b' : ('cp857', 'Turkish MS-DOS'), 
  84          '\x78' : ('cp950', 'Traditional Chinese (Hong Kong SAR, Taiwan) Windows'), 
  85          '\x79' : ('cp949', 'Korean Windows'), 
  86          '\x7a' : ('cp936', 'Chinese Simplified (PRC, Singapore) Windows'), 
  87          '\x7b' : ('cp932', 'Japanese Windows'), 
  88          '\x7c' : ('cp874', 'Thai Windows'), 
  89          '\x7d' : ('cp1255', 'Hebrew Windows'), 
  90          '\x7e' : ('cp1256', 'Arabic Windows'), 
  91          '\xc8' : ('cp1250', 'Eastern European Windows'), 
  92          '\xc9' : ('cp1251', 'Russian Windows'), 
  93          '\xca' : ('cp1254', 'Turkish Windows'), 
  94          '\xcb' : ('cp1253', 'Greek Windows'), 
  95          '\x96' : ('mac_cyrillic', 'Russian Macintosh'), 
  96          '\x97' : ('mac_latin2', 'Macintosh EE'), 
  97          '\x98' : ('mac_greek', 'Greek Macintosh') } 
  98   
  99  if sys.version_info[:2] < (2, 6): 
100 # define our own property type 101 - class property(object):
102 "Emulate PyProperty_Type() in Objects/descrobject.c" 103
104 - def __init__(self, fget=None, fset=None, fdel=None, doc=None):
105 self.fget = fget 106 self.fset = fset 107 self.fdel = fdel 108 self.__doc__ = doc or fget.__doc__
109 - def __call__(self, func):
110 self.fget = func 111 if not self.__doc__: 112 self.__doc__ = fget.__doc__
113 - def __get__(self, obj, objtype=None):
114 if obj is None: 115 return self 116 if self.fget is None: 117 raise AttributeError, "unreadable attribute" 118 return self.fget(obj)
119 - def __set__(self, obj, value):
120 if self.fset is None: 121 raise AttributeError, "can't set attribute" 122 self.fset(obj, value)
123 - def __delete__(self, obj):
124 if self.fdel is None: 125 raise AttributeError, "can't delete attribute" 126 self.fdel(obj)
127 - def setter(self, func):
128 self.fset = func 129 return self
130 - def deleter(self, func):
131 self.fdel = func 132 return self
133 -class _DbfRecord(object):
134 """Provides routines to extract and save data within the fields of a dbf record.""" 135 __slots__ = ['_recnum', '_layout', '_data', '__weakref__']
136 - def _retrieveFieldValue(yo, record_data, fielddef):
137 """calls appropriate routine to fetch value stored in field from array 138 @param record_data: the data portion of the record 139 @type record_data: array of characters 140 @param fielddef: description of the field definition 141 @type fielddef: dictionary with keys 'type', 'start', 'length', 'end', 'decimals', and 'flags' 142 @returns: python data stored in field""" 143 144 field_type = fielddef['type'] 145 retrieve = yo._layout.fieldtypes[field_type]['Retrieve'] 146 datum = retrieve(record_data, fielddef, yo._layout.memo) 147 if field_type in yo._layout.character_fields: 148 datum = yo._layout.decoder(datum)[0] 149 if yo._layout.return_ascii: 150 try: 151 datum = yo._layout.output_encoder(datum)[0] 152 except UnicodeEncodeError: 153 datum = unicodedata.normalize('NFD', datum).encode('ascii','ignore') 154 return datum
155 - def _updateFieldValue(yo, fielddef, value):
156 "calls appropriate routine to convert value to ascii bytes, and save it in record" 157 field_type = fielddef['type'] 158 update = yo._layout.fieldtypes[field_type]['Update'] 159 if field_type in yo._layout.character_fields: 160 if not isinstance(value, unicode): 161 if yo._layout.input_decoder is None: 162 raise NonUnicode("String not in unicode format, no default encoding specified") 163 value = yo._layout.input_decoder(value)[0] # input ascii => unicode 164 value = yo._layout.encoder(value)[0] # unicode => table ascii 165 bytes = array('c', update(value, fielddef, yo._layout.memo)) 166 size = fielddef['length'] 167 if len(bytes) > size: 168 raise DataOverflow("tried to store %d bytes in %d byte field" % (len(bytes), size)) 169 blank = array('c', ' ' * size) 170 start = fielddef['start'] 171 end = start + size 172 blank[:len(bytes)] = bytes[:] 173 yo._data[start:end] = blank[:] 174 yo._updateDisk(yo._recnum * yo._layout.header.record_length + yo._layout.header.start, yo._data.tostring())
175 - def _updateDisk(yo, location='', data=None):
176 if not yo._layout.inmemory: 177 if yo._recnum < 0: 178 raise DbfError("Attempted to update record that has been packed") 179 if location == '': 180 location = yo._recnum * yo._layout.header.record_length + yo._layout.header.start 181 if data is None: 182 data = yo._data 183 yo._layout.dfd.seek(location) 184 yo._layout.dfd.write(data)
185 - def __call__(yo, *specs):
186 results = [] 187 if not specs: 188 specs = yo._layout.index 189 specs = _normalize_tuples(tuples=specs, length=2, filler=[_nop]) 190 for field, func in specs: 191 results.append(func(yo[field])) 192 return tuple(results)
193
194 - def __contains__(yo, key):
195 return key in yo._layout.fields
196 - def __iter__(yo):
197 return (yo[field] for field in yo._layout.fields)
198 - def __getattr__(yo, name):
199 if name[0:2] == '__' and name[-2:] == '__': 200 raise AttributeError, 'Method %s is not implemented.' % name 201 elif not name in yo._layout.fields: 202 raise FieldMissing(name) 203 try: 204 fielddef = yo._layout[name] 205 value = yo._retrieveFieldValue(yo._data[fielddef['start']:fielddef['end']], fielddef) 206 return value 207 except DbfError, error: 208 error.message = "field --%s-- is %s -> %s" % (name, yo._layout.fieldtypes[fielddef['type']]['Type'], error.message) 209 raise
210 - def __getitem__(yo, item):
211 if type(item) == int: 212 if not -yo._layout.header.field_count <= item < yo._layout.header.field_count: 213 raise IndexError("Field offset %d is not in record" % item) 214 return yo[yo._layout.fields[item]] 215 elif type(item) == slice: 216 sequence = [] 217 for index in yo._layout.fields[item]: 218 sequence.append(yo[index]) 219 return sequence 220 elif type(item) == str: 221 return yo.__getattr__(item) 222 else: 223 raise TypeError("%s is not a field name" % item)
224 - def __len__(yo):
225 return yo._layout.header.field_count
226 - def __new__(cls, recnum, layout, kamikaze='', _fromdisk=False):
227 """record = ascii array of entire record; layout=record specification; memo = memo object for table""" 228 record = object.__new__(cls) 229 record._recnum = recnum 230 record._layout = layout 231 if layout.blankrecord is None and not _fromdisk: 232 record._createBlankRecord() 233 record._data = layout.blankrecord 234 if recnum == -1: # not a disk-backed record 235 return record 236 elif type(kamikaze) == array: 237 record._data = kamikaze[:] 238 elif type(kamikaze) == str: 239 record._data = array('c', kamikaze) 240 else: 241 record._data = kamikaze._data[:] 242 datalen = len(record._data) 243 if datalen < layout.header.record_length: 244 record._data.extend(layout.blankrecord[datalen:]) 245 elif datalen > layout.header.record_length: 246 record._data = record._data[:layout.header.record_length] 247 if not _fromdisk and not layout.inmemory: 248 record._updateDisk() 249 return record
250 - def __setattr__(yo, name, value):
251 if name in yo.__slots__: 252 object.__setattr__(yo, name, value) 253 return 254 elif not name in yo._layout.fields: 255 raise FieldMissing(name) 256 fielddef = yo._layout[name] 257 try: 258 yo._updateFieldValue(fielddef, value) 259 except DbfError, error: 260 error.message = "field --%s-- is %s -> %s" % (name, yo._layout.fieldtypes[fielddef['type']]['Type'], error.message) 261 error.data = name 262 raise 263 raise DbfError(message)
264 - def __setitem__(yo, name, value):
265 if type(name) == str: 266 yo.__setattr__(name, value) 267 elif type(name) in (int, long): 268 yo.__setattr__(yo._layout.fields[name], value) 269 else: 270 raise TypeError("%s is not a field name" % name)
271 - def __str__(yo):
272 result = [] 273 for field in yo.field_names: 274 result.append("%-10s: %s" % (field, yo[field])) 275 return '\n'.join(result)
276 - def __repr__(yo):
277 return yo._data.tostring()
278 - def _createBlankRecord(yo):
279 "creates a blank record data chunk" 280 layout = yo._layout 281 ondisk = layout.ondisk 282 layout.ondisk = False 283 yo._data = array('c', ' ' * layout.header.record_length) 284 layout.memofields = [] 285 for field in layout.fields: 286 yo._updateFieldValue(layout[field], layout.fieldtypes[layout[field]['type']]['Blank']()) 287 if layout[field]['type'] in layout.memotypes: 288 layout.memofields.append(field) 289 layout.blankrecord = yo._data[:] 290 layout.ondisk = ondisk
291 - def delete_record(yo):
292 "marks record as deleted" 293 yo._data[0] = '*' 294 yo._updateDisk(data='*')
295 @property
296 - def field_names(yo):
297 "fields in table/record" 298 return yo._layout.fields[:]
299 - def gather_fields(yo, dict, drop=False):
300 "saves a dictionary into a records fields\nkeys with no matching field will raise a FieldMissing exception unless drop = True" 301 for key in dict: 302 if not key in yo.field_names: 303 if drop: 304 continue 305 raise FieldMissing(key) 306 yo.__setattr__(key, dict[key])
307 @property
308 - def has_been_deleted(yo):
309 "marked for deletion?" 310 return yo._data[0] == '*'
311 @property
312 - def record_number(yo):
313 "physical record number" 314 return yo._recnum
315 @property
316 - def record_table(yo):
317 table = yo._layout.table() 318 if table is None: 319 raise DbfError("table is no longer available") 320 return table
321 - def reset_record(yo, keep_fields=None):
322 "blanks record" 323 if keep_fields is None: 324 keep_fields = [] 325 keep = {} 326 for field in keep_fields: 327 keep[field] = yo[field] 328 if yo._layout.blankrecord == None: 329 yo._createBlankRecord() 330 yo._data[:] = yo._layout.blankrecord[:] 331 for field in keep_fields: 332 yo[field] = keep[field] 333 yo._updateDisk()
334 - def scatter_fields(yo, blank=False):
335 "returns a dictionary of fieldnames and values which can be used with gather_fields(). if blank is True, values are empty." 336 keys = yo._layout.fields 337 if blank: 338 values = [yo._layout.fieldtypes[yo._layout[key]['type']]['Blank']() for key in keys] 339 else: 340 values = [yo[field] for field in keys] 341 return dict(zip(keys, values))
342 - def undelete_record(yo):
343 "marks record as active" 344 yo._data[0] = ' ' 345 yo._updateDisk(data=' ')
346 -class _DbfMemo(object):
347 """Provides access to memo fields as dictionaries 348 must override _init, _get_memo, and _put_memo to 349 store memo contents to disk"""
350 - def _init(yo):
351 "initialize disk file usage"
352 - def _get_memo(yo, block):
353 "retrieve memo contents from disk"
354 - def _put_memo(yo, data):
355 "store memo contents to disk"
356 - def __init__(yo, meta):
357 "" 358 yo.meta = meta 359 yo.memory = {} 360 yo.nextmemo = 1 361 yo._init() 362 yo.meta.newmemofile = False
363 - def get_memo(yo, block, field):
364 "gets the memo in block" 365 if yo.meta.ignorememos or not block: 366 return '' 367 if yo.meta.ondisk: 368 return yo._get_memo(block) 369 else: 370 return yo.memory[block]
371 - def put_memo(yo, data):
372 "stores data in memo file, returns block number" 373 if yo.meta.ignorememos or data == '': 374 return 0 375 if yo.meta.inmemory: 376 thismemo = yo.nextmemo 377 yo.nextmemo += 1 378 yo.memory[thismemo] = data 379 else: 380 thismemo = yo._put_memo(data) 381 return thismemo
382 -class _Db3Memo(_DbfMemo):
383 - def _init(yo):
384 "dBase III specific" 385 yo.meta.memo_size= 512 386 yo.record_header_length = 2 387 if yo.meta.ondisk and not yo.meta.ignorememos: 388 if yo.meta.newmemofile: 389 yo.meta.mfd = open(yo.meta.memoname, 'w+b') 390 yo.meta.mfd.write(io.packLongInt(1) + '\x00' * 508) 391 else: 392 try: 393 yo.meta.mfd = open(yo.meta.memoname, 'r+b') 394 yo.meta.mfd.seek(0) 395 yo.nextmemo = io.unpackLongInt(yo.meta.mfd.read(4)) 396 except: 397 raise DbfError("memo file appears to be corrupt")
398 - def _get_memo(yo, block):
399 block = int(block) 400 yo.meta.mfd.seek(block * yo.meta.memo_size) 401 eom = -1 402 data = '' 403 while eom == -1: 404 newdata = yo.meta.mfd.read(yo.meta.memo_size) 405 if not newdata: 406 return data 407 data += newdata 408 eom = data.find('\x1a\x1a') 409 return data[:eom].rstrip()
410 - def _put_memo(yo, data):
411 length = len(data) + yo.record_header_length # room for two ^Z at end of memo 412 blocks = length // yo.meta.memo_size 413 if length % yo.meta.memo_size: 414 blocks += 1 415 thismemo = yo.nextmemo 416 yo.nextmemo = thismemo + blocks 417 yo.meta.mfd.seek(0) 418 yo.meta.mfd.write(io.packLongInt(yo.nextmemo)) 419 yo.meta.mfd.seek(thismemo * yo.meta.memo_size) 420 yo.meta.mfd.write(data) 421 yo.meta.mfd.write('\x1a\x1a') 422 if len(yo._get_memo(thismemo)) != len(data): 423 raise DbfError("unknown error: memo not saved") 424 return thismemo
425 -class _VfpMemo(_DbfMemo):
426 - def _init(yo):
427 "Visual Foxpro 6 specific" 428 if yo.meta.ondisk and not yo.meta.ignorememos: 429 yo.record_header_length = 8 430 if yo.meta.newmemofile: 431 if yo.meta.memo_size == 0: 432 yo.meta.memo_size = 1 433 elif 1 < yo.meta.memo_size < 33: 434 yo.meta.memo_size *= 512 435 yo.meta.mfd = open(yo.meta.memoname, 'w+b') 436 nextmemo = 512 // yo.meta.memo_size 437 if nextmemo * yo.meta.memo_size < 512: 438 nextmemo += 1 439 yo.nextmemo = nextmemo 440 yo.meta.mfd.write(io.packLongInt(nextmemo, bigendian=True) + '\x00\x00' + \ 441 io.packShortInt(yo.meta.memo_size, bigendian=True) + '\x00' * 504) 442 else: 443 try: 444 yo.meta.mfd = open(yo.meta.memoname, 'r+b') 445 yo.meta.mfd.seek(0) 446 header = yo.meta.mfd.read(512) 447 yo.nextmemo = io.unpackLongInt(header[:4], bigendian=True) 448 yo.meta.memo_size = io.unpackShortInt(header[6:8], bigendian=True) 449 except: 450 raise DbfError("memo file appears to be corrupt")
451 - def _get_memo(yo, block):
452 yo.meta.mfd.seek(block * yo.meta.memo_size) 453 header = yo.meta.mfd.read(8) 454 length = io.unpackLongInt(header[4:], bigendian=True) 455 return yo.meta.mfd.read(length)
456 - def _put_memo(yo, data):
457 yo.meta.mfd.seek(0) 458 thismemo = io.unpackLongInt(yo.meta.mfd.read(4), bigendian=True) 459 yo.meta.mfd.seek(0) 460 length = len(data) + yo.record_header_length # room for two ^Z at end of memo 461 blocks = length // yo.meta.memo_size 462 if length % yo.meta.memo_size: 463 blocks += 1 464 yo.meta.mfd.write(io.packLongInt(thismemo+blocks, bigendian=True)) 465 yo.meta.mfd.seek(thismemo*yo.meta.memo_size) 466 yo.meta.mfd.write('\x00\x00\x00\x01' + io.packLongInt(len(data), bigendian=True) + data) 467 return thismemo
468 -class DbfTable(object):
469 """Provides a framework for dbf style tables.""" 470 _version = 'basic memory table' 471 _versionabbv = 'dbf' 472 _fieldtypes = { 473 'D' : { 'Type':'Date', 'Init':io.addDate, 'Blank':Date.today, 'Retrieve':io.retrieveDate, 'Update':io.updateDate, }, 474 'L' : { 'Type':'Logical', 'Init':io.addLogical, 'Blank':bool, 'Retrieve':io.retrieveLogical, 'Update':io.updateLogical, }, 475 'M' : { 'Type':'Memo', 'Init':io.addMemo, 'Blank':str, 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, } } 476 _memoext = '' 477 _memotypes = tuple('M', ) 478 _memoClass = _DbfMemo 479 _yesMemoMask = '' 480 _noMemoMask = '' 481 _fixed_fields = ('M','D','L') # always same length in table 482 _variable_fields = tuple() # variable length in table 483 _character_fields = tuple('M', ) # field representing character data 484 _decimal_fields = tuple() # text-based numeric fields 485 _numeric_fields = tuple() # fields representing a number 486 _dbfTableHeader = array('c', '\x00' * 32) 487 _dbfTableHeader[0] = '\x00' # table type - none 488 _dbfTableHeader[8:10] = array('c', io.packShortInt(33)) 489 _dbfTableHeader[10] = '\x01' # record length -- one for delete flag 490 _dbfTableHeader[29] = '\x00' # code page -- none, using plain ascii 491 _dbfTableHeader = _dbfTableHeader.tostring() 492 _dbfTableHeaderExtra = '' 493 _supported_tables = [] 494 _read_only = False 495 _meta_only = False 496 _use_deleted = True 497 _backed_up = False
498 - class _MetaData(dict):
499 blankrecord = None 500 fields = None 501 filename = None 502 dfd = None 503 memoname = None 504 newmemofile = False 505 memo = None 506 mfd = None 507 ignorememos = False 508 memofields = None 509 index = [] # never mutated 510 index_reversed = False 511 orderresults = None 512 current = -1
513 - class _TableHeader(object):
514 - def __init__(yo, data):
515 if len(data) != 32: 516 raise DbfError('table header should be 32 bytes, but is %d bytes' % len(data)) 517 yo._data = array('c', data + '\x0d')
518 - def codepage(yo, cp=None):
519 "get/set code page of table" 520 if cp is None: 521 return yo._data[29] 522 else: 523 if cp not in code_pages: 524 for code_page in sorted(code_pages.keys()): 525 sd, ld = code_pages[code_page] 526 if cp == sd or cp == ld: 527 if sd is None: 528 raise DbfError("Unsupported codepage: %s" % ld) 529 cp = code_page 530 break 531 else: 532 raise DbfError("Unsupported codepage: %s" % cp) 533 yo._data[29] = cp 534 return cp
535 @property
536 - def data(yo):
537 "main data structure" 538 date = io.packDate(Date.today()) 539 yo._data[1:4] = array('c', date) 540 return yo._data.tostring()
541 @data.setter
542 - def data(yo, bytes):
543 if len(bytes) < 32: 544 raise DbfError("length for data of %d is less than 32" % len(bytes)) 545 yo._data[:] = array('c', bytes)
546 @property
547 - def extra(yo):
548 "extra dbf info (located after headers, before data records)" 549 fieldblock = yo._data[32:] 550 for i in range(len(fieldblock)//32+1): 551 cr = i * 32 552 if fieldblock[cr] == '\x0d': 553 break 554 else: 555 raise DbfError("corrupt field structure") 556 cr += 33 # skip past CR 557 return yo._data[cr:].tostring()
558 @extra.setter
559 - def extra(yo, data):
560 fieldblock = yo._data[32:] 561 for i in range(len(fieldblock)//32+1): 562 cr = i * 32 563 if fieldblock[cr] == '\x0d': 564 break 565 else: 566 raise DbfError("corrupt field structure") 567 cr += 33 # skip past CR 568 yo._data[cr:] = array('c', data) # extra 569 yo._data[8:10] = array('c', io.packShortInt(len(yo._data))) # start
570 @property
571 - def field_count(yo):
572 "number of fields (read-only)" 573 fieldblock = yo._data[32:] 574 for i in range(len(fieldblock)//32+1): 575 cr = i * 32 576 if fieldblock[cr] == '\x0d': 577 break 578 else: 579 raise DbfError("corrupt field structure") 580 return len(fieldblock[:cr]) // 32
581 @property
582 - def fields(yo):
583 "field block structure" 584 fieldblock = yo._data[32:] 585 for i in range(len(fieldblock)//32+1): 586 cr = i * 32 587 if fieldblock[cr] == '\x0d': 588 break 589 else: 590 raise DbfError("corrupt field structure") 591 return fieldblock[:cr].tostring()
592 @fields.setter
593 - def fields(yo, block):
594 fieldblock = yo._data[32:] 595 for i in range(len(fieldblock)//32+1): 596 cr = i * 32 597 if fieldblock[cr] == '\x0d': 598 break 599 else: 600 raise DbfError("corrupt field structure") 601 cr += 32 # convert to indexing main structure 602 fieldlen = len(block) 603 if fieldlen % 32 != 0: 604 raise DbfError("fields structure corrupt: %d is not a multiple of 32" % fieldlen) 605 yo._data[32:cr] = array('c', block) # fields 606 yo._data[8:10] = array('c', io.packShortInt(len(yo._data))) # start 607 fieldlen = fieldlen // 32 608 recordlen = 1 # deleted flag 609 for i in range(fieldlen): 610 recordlen += ord(block[i*32+16]) 611 yo._data[10:12] = array('c', io.packShortInt(recordlen))
612 @property
613 - def record_count(yo):
614 "number of records (maximum 16,777,215)" 615 return io.unpackLongInt(yo._data[4:8].tostring())
616 @record_count.setter
617 - def record_count(yo, count):
618 yo._data[4:8] = array('c', io.packLongInt(count))
619 @property
620 - def record_length(yo):
621 "length of a record (read_only) (max of 65,535)" 622 return io.unpackShortInt(yo._data[10:12].tostring())
623 @property
624 - def start(yo):
625 "starting position of first record in file (must be within first 64K)" 626 return io.unpackShortInt(yo._data[8:10].tostring())
627 @start.setter
628 - def start(yo, pos):
629 yo._data[8:10] = array('c', io.packShortInt(pos))
630 @property
631 - def update(yo):
632 "date of last table modification (read-only)" 633 return io.unpackDate(yo._data[1:4].tostring())
634 @property
635 - def version(yo):
636 "dbf version" 637 return yo._data[0]
638 @version.setter
639 - def version(yo, ver):
640 yo._data[0] = ver
641 - class _Table(object):
642 "implements the weakref table for records"
643 - def __init__(yo, count, meta):
644 yo._meta = meta 645 yo._weakref_list = [weakref.ref(lambda x: None)] * count
646 - def __getitem__(yo, index):
647 maybe = yo._weakref_list[index]() 648 if maybe is None: 649 if index < 0: 650 index += yo._meta.header.record_count 651 size = yo._meta.header.record_length 652 location = index * size + yo._meta.header.start 653 yo._meta.dfd.seek(location) 654 bytes = yo._meta.dfd.read(size) 655 maybe = _DbfRecord(recnum=index, layout=yo._meta, kamikaze=bytes, _fromdisk=True) 656 yo._weakref_list[index] = weakref.ref(maybe) 657 return maybe
658 - def append(yo, record):
659 yo._weakref_list.append(weakref.ref(record))
660 - class DbfIterator(object):
661 "returns records using current index"
662 - def __init__(yo, table):
663 yo._table = table 664 yo._index = -1 665 yo._more_records = True
666 - def __iter__(yo):
667 return yo
668 - def next(yo):
669 while yo._more_records: 670 yo._index += 1 671 if yo._index >= len(yo._table): 672 yo._more_records = False 673 continue 674 record = yo._table[yo._index] 675 if not yo._table.use_deleted and record.has_been_deleted: 676 continue 677 return record 678 else: 679 raise StopIteration
680 - def _buildHeaderFields(yo):
681 "constructs fieldblock for disk table" 682 fieldblock = array('c', '') 683 memo = False 684 yo._meta.header.version = chr(ord(yo._meta.header.version) & ord(yo._noMemoMask)) 685 for field in yo._meta.fields: 686 if yo._meta.fields.count(field) > 1: 687 raise DbfError("corrupted field structure (noticed in _buildHeaderFields)") 688 fielddef = array('c', '\x00' * 32) 689 fielddef[:11] = array('c', io.packStr(field)) 690 fielddef[11] = yo._meta[field]['type'] 691 fielddef[12:16] = array('c', io.packLongInt(yo._meta[field]['start'])) 692 fielddef[16] = chr(yo._meta[field]['length']) 693 fielddef[17] = chr(yo._meta[field]['decimals']) 694 fielddef[18] = chr(yo._meta[field]['flags']) 695 fieldblock.extend(fielddef) 696 if yo._meta[field]['type'] in yo._meta.memotypes: 697 memo = True 698 yo._meta.header.fields = fieldblock.tostring() 699 if memo: 700 yo._meta.header.version = chr(ord(yo._meta.header.version) | ord(yo._yesMemoMask)) 701 if yo._meta.memo is None: 702 yo._meta.memo = yo._memoClass(yo._meta)
703 - def _checkMemoIntegrity(yo):
704 "dBase III specific" 705 if yo._meta.header.version == '\x83': 706 try: 707 yo._meta.memo = yo._memoClass(yo._meta) 708 except: 709 yo._meta.dfd.close() 710 yo._meta.dfd = None 711 raise 712 if not yo._meta.ignorememos: 713 for field in yo._meta.fields: 714 if yo._meta[field]['type'] in yo._memotypes: 715 if yo._meta.header.version != '\x83': 716 yo._meta.dfd.close() 717 yo._meta.dfd = None 718 raise DbfError("Table structure corrupt: memo fields exist, header declares no memos") 719 elif not os.path.exists(yo._meta.memoname): 720 yo._meta.dfd.close() 721 yo._meta.dfd = None 722 raise DbfError("Table structure corrupt: memo fields exist without memo file") 723 break
724 - def _initializeFields(yo):
725 "builds the FieldList of names, types, and descriptions from the disk file" 726 offset = 1 727 fieldsdef = yo._meta.header.fields 728 if len(fieldsdef) % 32 != 0: 729 raise DbfError("field definition block corrupt: %d bytes in size" % len(fieldsdef)) 730 if len(fieldsdef) // 32 != yo.field_count: 731 raise DbfError("Header shows %d fields, but field definition block has %d fields" % (yo.field_count, len(fieldsdef)//32)) 732 for i in range(yo.field_count): 733 fieldblock = fieldsdef[i*32:(i+1)*32] 734 name = io.unpackStr(fieldblock[:11]) 735 type = fieldblock[11] 736 if not type in yo._meta.fieldtypes: 737 raise DbfError("Unknown field type: %s" % type) 738 start = offset 739 length = ord(fieldblock[16]) 740 offset += length 741 end = start + length 742 decimals = ord(fieldblock[17]) 743 flags = ord(fieldblock[18]) 744 yo._meta.fields.append(name) 745 yo._meta[name] = {'type':type,'start':start,'length':length,'end':end,'decimals':decimals,'flags':flags}
746 - def _fieldLayout(yo, i):
747 "Returns field information Name Type(Length[,Decimals])" 748 name = yo._meta.fields[i] 749 type = yo._meta[name]['type'] 750 length = yo._meta[name]['length'] 751 decimals = yo._meta[name]['decimals'] 752 if type in yo._decimal_fields: 753 description = "%s %s(%d,%d)" % (name, type, length, decimals) 754 elif type in yo._fixed_fields: 755 description = "%s %s" % (name, type) 756 else: 757 description = "%s %s(%d)" % (name, type, length) 758 return description
759 - def _loadtable(yo):
760 "loads the records from disk to memory" 761 if yo._meta_only: 762 raise DbfError("%s has been closed, records are unavailable" % yo.filename) 763 dfd = yo._meta.dfd 764 header = yo._meta.header 765 dfd.seek(header.start) 766 allrecords = dfd.read() # kludge to get around mysterious errno 0 problems 767 dfd.seek(0) 768 length = header.record_length 769 for i in range(header.record_count): 770 record_data = allrecords[length*i:length*i+length] 771 yo._table.append(_DbfRecord(i, yo._meta, allrecords[length*i:length*i+length], _fromdisk=True)) 772 yo._index.append(i) 773 dfd.seek(0)
774 - def _list_fields(yo, specs, sep=','):
775 if specs is None: 776 specs = yo.field_names 777 elif isinstance(specs, str): 778 specs = specs.split(sep) 779 else: 780 specs = list(specs) 781 specs = [s.strip() for s in specs] 782 return specs
783 - def _updateDisk(yo, headeronly=False):
784 "synchronizes the disk file with current data" 785 if yo._meta.inmemory: 786 return 787 fd = yo._meta.dfd 788 fd.seek(0) 789 fd.write(yo._meta.header.data) 790 if not headeronly: 791 for record in yo._table: 792 record._updateDisk() 793 fd.flush() 794 fd.truncate(yo._meta.header.start + yo._meta.header.record_count * yo._meta.header.record_length)
795 - def __contains__(yo, key):
796 return key in yo.field_names
797 - def __enter__(yo):
798 return yo
799 - def __exit__(yo, *exc_info):
800 yo.close()
801 - def __getattr__(yo, name):
802 if name in ('_index','_table'): 803 if yo._meta.ondisk: 804 yo._table = yo._Table(len(yo), yo._meta) 805 yo._index = range(len(yo)) 806 else: 807 yo._table = [] 808 yo._index = [] 809 yo._loadtable() 810 return object.__getattribute__(yo, name)
811 - def __getitem__(yo, value):
812 if type(value) == int: 813 if not -yo._meta.header.record_count <= value < yo._meta.header.record_count: 814 raise IndexError("Record %d is not in table." % value) 815 return yo._table[yo._index[value]] 816 elif type(value) == slice: 817 sequence = DbfList(desc='%s --> %s' % (yo.filename, value)) 818 for index in yo._index[value]: 819 record = yo._table[index] 820 if yo.use_deleted is True or not record.has_been_deleted: 821 sequence.append(record) 822 return sequence 823 else: 824 raise TypeError('type <%s> not valid for indexing' % type(value))
825 - def __init__(yo, filename=':memory:', field_specs=None, memo_size=128, ignore_memos=False, 826 read_only=False, keep_memos=False, meta_only=False, codepage=None):
827 """open/create dbf file 828 filename should include path if needed 829 field_specs can be either a ;-delimited string or a list of strings 830 memo_size is always 512 for db3 memos 831 ignore_memos is useful if the memo file is missing or corrupt 832 read_only will load records into memory, then close the disk file 833 keep_memos will also load any memo fields into memory 834 meta_only will ignore all records, keeping only basic table information 835 codepage will override whatever is set in the table itself""" 836 if filename == ':memory:': 837 if field_specs is None: 838 raise DbfError("field list must be specified for in-memory tables") 839 elif type(yo) is DbfTable: 840 raise DbfError("only memory tables supported") 841 yo._meta = meta = yo._MetaData() 842 meta.table = weakref.ref(yo) 843 meta.filename = filename 844 meta.fields = [] 845 meta.fieldtypes = yo._fieldtypes 846 meta.fixed_fields = yo._fixed_fields 847 meta.variable_fields = yo._variable_fields 848 meta.character_fields = yo._character_fields 849 meta.decimal_fields = yo._decimal_fields 850 meta.numeric_fields = yo._numeric_fields 851 meta.memotypes = yo._memotypes 852 meta.ignorememos = ignore_memos 853 meta.memo_size = memo_size 854 meta.input_decoder = codecs.getdecoder(input_decoding) # from ascii to unicode 855 meta.output_encoder = codecs.getencoder(input_decoding) # and back to ascii 856 meta.return_ascii = return_ascii 857 meta.header = header = yo._TableHeader(yo._dbfTableHeader) 858 header.extra = yo._dbfTableHeaderExtra 859 header.data #force update of date 860 yo.codepage = codepage or default_codepage 861 if filename == ':memory:': 862 yo._index = [] 863 yo._table = [] 864 meta.ondisk = False 865 meta.inmemory = True 866 meta.memoname = ':memory:' 867 else: 868 base, ext = os.path.splitext(filename) 869 if ext == '': 870 meta.filename = base + '.dbf' 871 meta.memoname = base + yo._memoext 872 meta.ondisk = True 873 meta.inmemory = False 874 if field_specs: 875 if meta.ondisk: 876 meta.dfd = open(meta.filename, 'w+b') 877 meta.newmemofile = True 878 yo.add_fields(field_specs) 879 return 880 dfd = meta.dfd = open(meta.filename, 'r+b') 881 dfd.seek(0) 882 meta.header = header = yo._TableHeader(dfd.read(32)) 883 if not header.version in yo._supported_tables: 884 dfd.close() 885 dfd = None 886 raise TypeError("Unsupported dbf type: %s [%x]" % (version_map.get(meta.header.version, 'Unknown: %s' % meta.header.version), ord(meta.header.version))) 887 yo.codepage = meta.header.codepage() 888 fieldblock = dfd.read(header.start - 32) 889 for i in range(len(fieldblock)//32+1): 890 fieldend = i * 32 891 if fieldblock[fieldend] == '\x0d': 892 break 893 else: 894 raise DbfError("corrupt field structure in header") 895 if len(fieldblock[:fieldend]) % 32 != 0: 896 raise DbfError("corrupt field structure in header") 897 header.fields = fieldblock[:fieldend] 898 header.extra = fieldblock[fieldend+1:] # skip trailing \r 899 yo._initializeFields() 900 yo._checkMemoIntegrity() 901 meta.current = -1 902 if len(yo) > 0: 903 meta.current = 0 904 dfd.seek(0) 905 if meta_only: 906 yo.close(keep_table=False, keep_memos=False) 907 elif read_only: 908 yo.close(keep_table=True, keep_memos=keep_memos)
909 - def __iter__(yo):
910 return yo.DbfIterator(yo)
911 - def __len__(yo):
912 return yo._meta.header.record_count
913 - def __nonzero__(yo):
914 return yo._meta.header.record_count != 0
915 - def __repr__(yo):
916 if yo._read_only: 917 return __name__ + ".Table('%s', read_only=True)" % yo._meta.filename 918 elif yo._meta_only: 919 return __name__ + ".Table('%s', meta_only=True)" % yo._meta.filename 920 else: 921 return __name__ + ".Table('%s')" % yo._meta.filename
922 - def __str__(yo):
923 if yo._read_only: 924 status = "read-only" 925 elif yo._meta_only: 926 status = "meta-only" 927 else: 928 status = "read/write" 929 str = """ 930 Table: %s 931 Type: %s 932 Codepage: %s 933 Status: %s 934 Last updated: %s 935 Record count: %d 936 Field count: %d 937 Record length: %d 938 """ % (yo.filename, version_map.get(yo._meta.header.version, 'unknown - ' + hex(ord(yo._meta.header.version))), 939 yo.codepage, status, yo.last_update, len(yo), yo.field_count, yo.record_length) 940 str += "\n --Fields--\n" 941 for i in range(len(yo._meta.fields)): 942 str += " " + yo._fieldLayout(i) + "\n" 943 return str
944 @property
945 - def codepage(yo):
946 return "%s (%s)" % code_pages[yo._meta.header.codepage()]
947 @codepage.setter
948 - def codepage(yo, cp):
949 result = yo._meta.header.codepage(cp) 950 yo._meta.decoder = codecs.getdecoder(code_pages[result][0]) 951 yo._meta.encoder = codecs.getencoder(code_pages[result][0])
952 @property
953 - def field_count(yo):
954 "the number of fields in the table" 955 return yo._meta.header.field_count
956 @property
957 - def field_names(yo):
958 "a list of the fields in the table" 959 return yo._meta.fields[:]
960 @property
961 - def filename(yo):
962 "table's file name, including path (if specified on open)" 963 return yo._meta.filename
964 @property
965 - def last_update(yo):
966 "date of last update" 967 return yo._meta.header.update
968 @property
969 - def memoname(yo):
970 "table's memo name (if path included in filename on open)" 971 return yo._meta.memoname
972 @property
973 - def record_length(yo):
974 "number of bytes in a record" 975 return yo._meta.header.record_length
976 @property
977 - def record_number(yo):
978 "index number of the current record" 979 return yo._meta.current
980 @property
981 - def supported_tables(yo):
982 "allowable table types" 983 return yo._supported_tables
984 @property
985 - def use_deleted(yo):
986 "process or ignore deleted records" 987 return yo._use_deleted
988 @use_deleted.setter
989 - def use_deleted(yo, new_setting):
990 yo._use_deleted = new_setting
991 @property
992 - def version(yo):
993 "returns the dbf type of the table" 994 return yo._version
995 - def add_fields(yo, field_specs):
996 """adds field(s) to the table layout; format is Name Type(Length,Decimals)[; Name Type(Length,Decimals)[...]] 997 backup table is created with _backup appended to name 998 then modifies current structure""" 999 all_records = [record for record in yo] 1000 if yo: 1001 yo.create_backup() 1002 yo._meta.blankrecord = None 1003 meta = yo._meta 1004 offset = meta.header.record_length 1005 fields = yo._list_fields(field_specs, sep=';') 1006 for field in fields: 1007 try: 1008 name, format = field.split() 1009 if name[0] == '_' or name[0].isdigit() or not name.replace('_','').isalnum(): 1010 raise DbfError("Field names cannot start with _ or digits, and can only contain the _, letters, and digits") 1011 name = name.lower() 1012 if name in meta.fields: 1013 raise DbfError("Field '%s' already exists" % name) 1014 field_type = format[0].upper() 1015 if len(name) > 10: 1016 raise DbfError("Maximum field name length is 10. '%s' is %d characters long." % (name, len(name))) 1017 if not field_type in meta.fieldtypes.keys(): 1018 raise DbfError("Unknown field type: %s" % field_type) 1019 length, decimals = yo._meta.fieldtypes[field_type]['Init'](format) 1020 except ValueError: 1021 raise DbfError("invalid field specifier: %s" % field) 1022 start = offset 1023 end = offset + length 1024 offset = end 1025 meta.fields.append(name) 1026 meta[name] = {'type':field_type, 'start':start, 'length':length, 'end':end, 'decimals':decimals, 'flags':0} 1027 if meta[name]['type'] in yo._memotypes and meta.memo is None: 1028 meta.memo = yo._memoClass(meta) 1029 for record in yo: 1030 record[name] = meta.fieldtypes[field_type]['Blank']() 1031 yo._buildHeaderFields() 1032 yo._updateDisk()
1033 - def append(yo, kamikaze='', drop=False, multiple=1):
1034 "adds <multiple> blank records, and fills fields with dict/tuple values if present" 1035 if not yo.field_count: 1036 raise DbfError("No fields defined, cannot append") 1037 empty_table = len(yo) == 0 1038 dictdata = False 1039 tupledata = False 1040 if not isinstance(kamikaze, _DbfRecord): 1041 if isinstance(kamikaze, dict): 1042 dictdata = kamikaze 1043 kamikaze = '' 1044 elif isinstance(kamikaze, tuple): 1045 tupledata = kamikaze 1046 kamikaze = '' 1047 newrecord = _DbfRecord(recnum=yo._meta.header.record_count, layout=yo._meta, kamikaze=kamikaze) 1048 yo._table.append(newrecord) 1049 yo._index.append(yo._meta.header.record_count) 1050 yo._meta.header.record_count += 1 1051 if dictdata: 1052 newrecord.gather_fields(dictdata, drop) 1053 elif tupledata: 1054 for index, item in enumerate(tupledata): 1055 newrecord[index] = item 1056 elif kamikaze == str: 1057 for field in yo._meta.memofields: 1058 newrecord[field] = '' 1059 elif kamikaze: 1060 for field in yo._meta.memofields: 1061 newrecord[field] = kamikaze[field] 1062 multiple -= 1 1063 if multiple: 1064 data = newrecord._data 1065 single = yo._meta.header.record_count 1066 total = single + multiple 1067 while single < total: 1068 multi_record = _DbfRecord(single, yo._meta, kamikaze=data) 1069 yo._table.append(multi_record) 1070 yo._index.append(single) 1071 for field in yo._meta.memofields: 1072 multi_record[field] = newrecord[field] 1073 single += 1 1074 yo._meta.header.record_count = total # += multiple 1075 yo._meta.current = yo._meta.header.record_count - 1 1076 newrecord = multi_record 1077 yo._updateDisk(headeronly=True) 1078 if empty_table: 1079 yo._meta.current = 0 1080 return newrecord
1081 - def bof(yo):
1082 "moves record pointer to previous usable record; returns True if no more usable records" 1083 while yo._meta.current > 0: 1084 yo._meta.current -= 1 1085 if yo.use_deleted or not yo.current().has_been_deleted: 1086 break 1087 else: 1088 yo._meta.current = -1 1089 return True 1090 return False
1091 - def bottom(yo, get_record=False):
1092 """sets record pointer to bottom of table 1093 if get_record, seeks to and returns last (non-deleted) record 1094 DbfError if table is empty 1095 Bof if all records deleted and use_deleted is False""" 1096 yo._meta.current = yo._meta.header.record_count 1097 if get_record: 1098 try: 1099 return yo.prev() 1100 except Bof: 1101 yo._meta.current = yo._meta.header.record_count 1102 raise Eof()
1103 - def close(yo, keep_table=False, keep_memos=False):
1104 """closes disk files 1105 ensures table data is available if keep_table 1106 ensures memo data is available if keep_memos""" 1107 if keep_table: 1108 yo._table # force read of table if not already in memory 1109 else: 1110 if '_index' in dir(yo): 1111 del yo._table 1112 del yo._index 1113 yo._meta.inmemory = True 1114 if yo._meta.ondisk: 1115 yo._meta.dfd.close() 1116 yo._meta.dfd = None 1117 if '_index' in dir(yo): 1118 yo._read_only = True 1119 else: 1120 yo._meta_only = True 1121 if yo._meta.mfd is not None: 1122 if not keep_memos: 1123 yo._meta.ignorememos = True 1124 else: 1125 memo_fields = [] 1126 for field in yo.field_names: 1127 if yo.is_memotype(field): 1128 memo_fields.append(field) 1129 for record in yo: 1130 for field in memo_fields: 1131 record[field] = record[field] 1132 yo._meta.mfd.close() 1133 yo._meta.mfd = None 1134 yo._meta.ondisk = False
1135 - def create_backup(yo, new_name=None, overwrite=False):
1136 "creates a backup table -- ignored if memory table" 1137 if yo.filename.startswith(':memory:'): 1138 return 1139 if new_name is None: 1140 new_name = os.path.splitext(yo.filename)[0] + '_backup.dbf' 1141 else: 1142 overwrite = True 1143 if overwrite or not yo._backed_up: 1144 bkup = open(new_name, 'wb') 1145 try: 1146 yo._meta.dfd.seek(0) 1147 copyfileobj(yo._meta.dfd, bkup) 1148 yo._backed_up = True 1149 finally: 1150 bkup.close()
1151 - def current(yo, index=False):
1152 "returns current logical record, or its index" 1153 if yo._meta.current < 0: 1154 raise Bof() 1155 elif yo._meta.current >= yo._meta.header.record_count: 1156 raise Eof() 1157 if index: 1158 return yo._meta.current 1159 return yo._table[yo._index[yo._meta.current]]
1160 - def delete_fields(yo, doomed):
1161 """removes field(s) from the table 1162 creates backup files with _backup appended to the file name, 1163 then modifies current structure""" 1164 doomed = yo._list_fields(doomed) 1165 for victim in doomed: 1166 if victim not in yo._meta.fields: 1167 raise DbfError("field %s not in table -- delete aborted" % victim) 1168 all_records = [record for record in yo] 1169 yo.create_backup() 1170 for victim in doomed: 1171 yo._meta.fields.pop(yo._meta.fields.index(victim)) 1172 start = yo._meta[victim]['start'] 1173 end = yo._meta[victim]['end'] 1174 for record in yo: 1175 record._data = record._data[:start] + record._data[end:] 1176 for field in yo._meta.fields: 1177 if yo._meta[field]['start'] == end: 1178 end = yo._meta[field]['end'] 1179 yo._meta[field]['start'] = start 1180 yo._meta[field]['end'] = start + yo._meta[field]['length'] 1181 start = yo._meta[field]['end'] 1182 yo._buildHeaderFields() 1183 yo._updateDisk()
1184 - def eof(yo):
1185 "moves record pointer to next usable record; returns True if no more usable records" 1186 while yo._meta.current < yo._meta.header.record_count - 1: 1187 yo._meta.current += 1 1188 if yo.use_deleted or not yo.current().has_been_deleted: 1189 break 1190 else: 1191 yo._meta.current = yo._meta.header.record_count 1192 return True 1193 return False
1194 - def export(yo, records=None, filename=None, field_specs=None, format='csv', header=True):
1195 """writes the table using CSV or tab-delimited format, using the filename 1196 given if specified, otherwise the table name""" 1197 if filename is None: 1198 filename = yo.filename 1199 field_specs = yo._list_fields(field_specs) 1200 if records is None: 1201 records = yo 1202 format = format.lower() 1203 if format not in ('csv', 'tab'): 1204 raise DbfError("export format: csv or tab, not %s" % format) 1205 base, ext = os.path.splitext(filename) 1206 if ext.lower() in ('', '.dbf'): 1207 filename = base + "." + format 1208 fd = open(filename, 'wb') 1209 try: 1210 if format == 'csv': 1211 csvfile = csv.writer(fd, dialect='dbf') 1212 if header: 1213 csvfile.writerow(field_specs) 1214 for record in records: 1215 fields = [] 1216 for fieldname in field_specs: 1217 fields.append(record[fieldname]) 1218 csvfile.writerow(fields) 1219 else: 1220 if header: 1221 fd.write('\t'.join(field_specs) + '\n') 1222 for record in records: 1223 fields = [] 1224 for fieldname in field_specs: 1225 fields.append(str(record[fieldname])) 1226 fd.write('\t'.join(fields) + '\n') 1227 finally: 1228 fd.close() 1229 fd = None 1230 return len(records)
1231 - def get_record(yo, recno):
1232 "returns record at physical_index[recno]" 1233 return yo._table[recno]
1234 - def goto(yo, criteria):
1235 """changes the record pointer to the first matching (non-deleted) record 1236 criteria should be either a tuple of tuple(value, field, func) triples, 1237 or an integer to go to""" 1238 if isinstance(criteria, int): 1239 if not -yo._meta.header.record_count <= criteria < yo._meta.header.record_count: 1240 raise IndexError("Record %d does not exist" % criteria) 1241 if criteria < 0: 1242 criteria += yo._meta.header.record_count 1243 yo._meta.current = criteria 1244 return yo.current() 1245 criteria = _normalize_tuples(tuples=criteria, length=3, filler=[_nop]) 1246 specs = tuple([(field, func) for value, field, func in criteria]) 1247 match = tuple([value for value, field, func in criteria]) 1248 current = yo.current(index=True) 1249 matchlen = len(match) 1250 while not yo.Eof(): 1251 record = yo.current() 1252 results = record(*specs) 1253 if results == match: 1254 return record 1255 return yo.goto(current)
1256 - def index(yo, sort=None, reverse=False):
1257 "orders the table using the tuple provided; removes index if no sort provided" 1258 if sort is None: 1259 results = [] 1260 for field, func in yo._meta.index: 1261 results.append("%s(%s)" % (func.__name__, field)) 1262 return ', '.join(results + ['reverse=%s' % yo._meta.index_reversed]) 1263 yo._meta.index_reversed = reverse 1264 if sort == 'ORIGINAL': 1265 yo._index = range(yo._meta.header.record_count) 1266 yo._meta.index = [] 1267 if reverse: 1268 yo._index.reverse() 1269 return 1270 new_sort = _normalize_tuples(tuples=sort, length=2, filler=[_nop]) 1271 yo._meta.index = tuple(new_sort) 1272 yo._meta.orderresults = [''] * len(yo) 1273 for record in yo: 1274 yo._meta.orderresults[record.record_number] = record() 1275 yo._index.sort(key=lambda i: yo._meta.orderresults[i], reverse=reverse)
1276 - def is_memotype(yo, name):
1277 "returns True if name is a memo type field" 1278 return yo._meta[name]['type'] in yo._memotypes
1279 - def new(yo, filename, _field_specs=None):
1280 "returns a new table of the same type" 1281 if _field_specs is None: 1282 _field_specs = yo.structure() 1283 if filename != ':memory:': 1284 path, name = os.path.split(filename) 1285 if path == "": 1286 filename = os.path.join(os.path.split(yo.filename)[0], filename) 1287 elif name == "": 1288 filename = os.path.join(path, os.path.split(yo.filename)[1]) 1289 return yo.__class__(filename, _field_specs)
1290 - def next(yo):
1291 "set record pointer to next (non-deleted) record, and return it" 1292 if yo.eof(): 1293 raise Eof() 1294 return yo.current()
1295 - def pack(yo, _pack=True):
1296 "physically removes all deleted records" 1297 newtable = [] 1298 newindex = [] 1299 i = 0 1300 for record in yo._table: 1301 if record.has_been_deleted and _pack: 1302 record._recnum = -1 1303 else: 1304 record._recnum = i 1305 newtable.append(record) 1306 newindex.append(i) 1307 i += 1 1308 yo._table = newtable 1309 yo._index = newindex 1310 yo._meta.header.record_count = i 1311 yo._current = -1 1312 yo._meta.index = '' 1313 yo._updateDisk()
1314 - def prev(yo):
1315 "set record pointer to previous (non-deleted) record, and return it" 1316 if yo.bof(): 1317 raise Bof 1318 return yo.current()
1319 - def query(yo, sql=None, python=None):
1320 "uses exec to perform python queries on the table" 1321 if python is None: 1322 raise DbfError("query: python parameter must be specified") 1323 possible = DbfList(desc="%s --> %s" % (yo.filename, python)) 1324 query_result = {} 1325 select = 'query_result["keep"] = %s' % python 1326 g = {} 1327 for record in yo: 1328 query_result['keep'] = False 1329 g['query_result'] = query_result 1330 exec select in g, record 1331 if query_result['keep']: 1332 possible.append(record) 1333 return possible
1334 - def rename_field(yo, oldname, newname):
1335 "renames an existing field" 1336 if yo: 1337 yo.create_backup() 1338 if not oldname in yo._meta.fields: 1339 raise DbfError("field --%s-- does not exist -- cannot rename it." % oldname) 1340 if newname[0] == '_' or newname[0].isdigit() or not newname.replace('_','').isalnum(): 1341 raise DbfError("field names cannot start with _ or digits, and can only contain the _, letters, and digits") 1342 newname = newname.lower() 1343 if newname in yo._meta.fields: 1344 raise DbfError("field --%s-- already exists" % newname) 1345 if len(newname) > 10: 1346 raise DbfError("maximum field name length is 10. '%s' is %d characters long." % (newname, len(newname))) 1347 yo._meta[newname] = yo._meta[oldname] 1348 yo._meta.fields[yo._meta.fields.index(oldname)] = newname 1349 yo._buildHeaderFields() 1350 yo._updateDisk(headeronly=True)
1351 - def search(yo, match, fuzzy=None, indices=False):
1352 """searches using a binary algorythm 1353 looking for records that match the criteria in match, which is a tuple 1354 with a data item per ordered field. table must be sorted. if index, 1355 returns a list of records' indices from the current sort order. 1356 """ 1357 if yo._meta.index is None: 1358 raise DbfError('table must be indexed to use Search') 1359 matchlen = len(match) 1360 if fuzzy: 1361 matchlen -= 1 1362 fuzzy_match = match[-1] 1363 fuzzy_field = yo._meta.index[matchlen][0] 1364 match = match[:-1] 1365 records = DbfList(desc="%s --> search: index=%s, match=%s, fuzzy=%s(%s))" % (yo.filename, yo.index(), match, fuzzy.__name__, fuzzy_match)) 1366 else: 1367 records = DbfList(desc="%s --> search: index=%s, match=%s)" % (yo.filename, yo.index(), match)) 1368 if indices: 1369 records = [] 1370 if not isinstance(match, tuple): 1371 match = tuple(match) 1372 segment = len(yo) 1373 current = 0 1374 toosoon = True 1375 notFound = True 1376 while notFound: 1377 segment = segment // 2 1378 if toosoon: 1379 current += segment 1380 else: 1381 current -= segment 1382 if current % 2: 1383 segment += 1 1384 if current == len(yo) or segment == 0: 1385 break 1386 value = yo._meta.orderresults[yo[current].record_number][:matchlen] 1387 if value < match: 1388 toosoon = True 1389 elif value > match: 1390 toosoon = False 1391 else: 1392 notFound = False 1393 break 1394 if current == 0: 1395 break 1396 if notFound: 1397 return records 1398 while current > 0: 1399 current -= 1 1400 value = yo._meta.orderresults[yo[current].record_number][:matchlen] 1401 if value != match: 1402 current += 1 1403 break 1404 while True: 1405 value = yo._meta.orderresults[yo[current].record_number][:matchlen] 1406 if value != match: 1407 break 1408 if yo.use_deleted or not yo[current].has_been_deleted: 1409 if indices: 1410 records.append(current) 1411 else: 1412 records.append(yo[current]) 1413 current += 1 1414 if current == len(yo): 1415 break 1416 if fuzzy: 1417 if indices: 1418 records = [rec for rec in records if fuzzy(yo[rec][fuzzy_field]) == fuzzy_match] 1419 else: 1420 final_records = [rec for rec in records if fuzzy(rec[fuzzy_field]) == fuzzy_match] 1421 records.clear() 1422 records.extend(final_records) 1423 return records
1424 - def size(yo, field):
1425 "returns size of field as a tuple of (length, decimals)" 1426 if field in yo: 1427 return (yo._meta[field]['length'], yo._meta[field]['decimals']) 1428 raise DbfError("%s is not a field in %s" % (field, yo.filename))
1429 - def structure(yo, fields=None):
1430 """return list of fields suitable for creating same table layout 1431 @param fields: list of fields or None for all fields""" 1432 field_specs = [] 1433 fields = yo._list_fields(fields) 1434 try: 1435 for name in fields: 1436 field_specs.append(yo._fieldLayout(yo.field_names.index(name))) 1437 except ValueError: 1438 raise DbfError("field --%s-- does not exist" % name) 1439 return field_specs
1440 - def top(yo, get_record=False):
1441 """sets record pointer to top of table; if get_record, seeks to and returns first (non-deleted) record 1442 DbfError if table is empty 1443 Eof if all records are deleted and use_deleted is False""" 1444 yo._meta.current = -1 1445 if get_record: 1446 try: 1447 return yo.next() 1448 except Eof: 1449 yo._meta.current = -1 1450 raise Bof()
1451 - def type(yo, field):
1452 "returns type of field" 1453 if field in yo: 1454 return yo._meta[field]['type'] 1455 raise DbfError("%s is not a field in %s" % (field, yo.filename))
1456 - def zap(yo, areyousure=False):
1457 """removes all records from table -- this cannot be undone! 1458 areyousure must be True, else error is raised""" 1459 if areyousure: 1460 yo._table = [] 1461 yo._index = [] 1462 yo._meta.header.record_count = 0 1463 yo._current = -1 1464 yo._meta.index = '' 1465 yo._updateDisk() 1466 else: 1467 raise DbfError("You must say you are sure to wipe the table")
1468 # these asignments are for backward compatibility, and will go away
1469 -class Db3Table(DbfTable):
1470 """Provides an interface for working with dBase III tables.""" 1471 _version = 'dBase III Plus' 1472 _versionabbv = 'db3' 1473 _fieldtypes = { 1474 'C' : {'Type':'Character', 'Retrieve':io.retrieveCharacter, 'Update':io.updateCharacter, 'Blank':str, 'Init':io.addCharacter}, 1475 'D' : {'Type':'Date', 'Retrieve':io.retrieveDate, 'Update':io.updateDate, 'Blank':Date.today, 'Init':io.addDate}, 1476 'L' : {'Type':'Logical', 'Retrieve':io.retrieveLogical, 'Update':io.updateLogical, 'Blank':bool, 'Init':io.addLogical}, 1477 'M' : {'Type':'Memo', 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, 'Blank':str, 'Init':io.addMemo}, 1478 'N' : {'Type':'Numeric', 'Retrieve':io.retrieveNumeric, 'Update':io.updateNumeric, 'Blank':int, 'Init':io.addNumeric} } 1479 _memoext = '.dbt' 1480 _memotypes = ('M',) 1481 _memoClass = _Db3Memo 1482 _yesMemoMask = '\x80' 1483 _noMemoMask = '\x7f' 1484 _fixed_fields = ('D','L','M') 1485 _variable_fields = ('C','N') 1486 _character_fields = ('C','M') 1487 _decimal_fields = ('N',) 1488 _numeric_fields = ('N',) 1489 _dbfTableHeader = array('c', '\x00' * 32) 1490 _dbfTableHeader[0] = '\x03' # version - dBase III w/o memo's 1491 _dbfTableHeader[8:10] = array('c', io.packShortInt(33)) 1492 _dbfTableHeader[10] = '\x01' # record length -- one for delete flag 1493 _dbfTableHeader[29] = '\x03' # code page -- 437 US-MS DOS 1494 _dbfTableHeader = _dbfTableHeader.tostring() 1495 _dbfTableHeaderExtra = '' 1496 _supported_tables = ['\x03', '\x83'] 1497 _read_only = False 1498 _meta_only = False 1499 _use_deleted = True
1500 - def _checkMemoIntegrity(yo):
1501 "dBase III specific" 1502 if yo._meta.header.version == '\x83': 1503 try: 1504 yo._meta.memo = yo._memoClass(yo._meta) 1505 except: 1506 yo._meta.dfd.close() 1507 yo._meta.dfd = None 1508 raise 1509 if not yo._meta.ignorememos: 1510 for field in yo._meta.fields: 1511 if yo._meta[field]['type'] in yo._memotypes: 1512 if yo._meta.header.version != '\x83': 1513 yo._meta.dfd.close() 1514 yo._meta.dfd = None 1515 raise DbfError("Table structure corrupt: memo fields exist, header declares no memos") 1516 elif not os.path.exists(yo._meta.memoname): 1517 yo._meta.dfd.close() 1518 yo._meta.dfd = None 1519 raise DbfError("Table structure corrupt: memo fields exist without memo file") 1520 break
1521 - def _initializeFields(yo):
1522 "builds the FieldList of names, types, and descriptions" 1523 offset = 1 1524 fieldsdef = yo._meta.header.fields 1525 if len(fieldsdef) % 32 != 0: 1526 raise DbfError("field definition block corrupt: %d bytes in size" % len(fieldsdef)) 1527 if len(fieldsdef) // 32 != yo.field_count: 1528 raise DbfError("Header shows %d fields, but field definition block has %d fields" % (yo.field_count, len(fieldsdef)//32)) 1529 for i in range(yo.field_count): 1530 fieldblock = fieldsdef[i*32:(i+1)*32] 1531 name = io.unpackStr(fieldblock[:11]) 1532 type = fieldblock[11] 1533 if not type in yo._meta.fieldtypes: 1534 raise DbfError("Unknown field type: %s" % type) 1535 start = offset 1536 length = ord(fieldblock[16]) 1537 offset += length 1538 end = start + length 1539 decimals = ord(fieldblock[17]) 1540 flags = ord(fieldblock[18]) 1541 yo._meta.fields.append(name) 1542 yo._meta[name] = {'type':type,'start':start,'length':length,'end':end,'decimals':decimals,'flags':flags}
1543 -class FpTable(DbfTable):
1544 'Provides an interface for working with FoxPro 2 tables' 1545 _version = 'Foxpro' 1546 _versionabbv = 'fp' 1547 _fieldtypes = { 1548 'C' : {'Type':'Character', 'Retrieve':io.retrieveCharacter, 'Update':io.updateCharacter, 'Blank':str, 'Init':io.addCharacter}, 1549 'F' : {'Type':'Float', 'Retrieve':io.retrieveNumeric, 'Update':io.updateNumeric, 'Blank':float, 'Init':io.addVfpNumeric}, 1550 'N' : {'Type':'Numeric', 'Retrieve':io.retrieveNumeric, 'Update':io.updateNumeric, 'Blank':int, 'Init':io.addVfpNumeric}, 1551 'L' : {'Type':'Logical', 'Retrieve':io.retrieveLogical, 'Update':io.updateLogical, 'Blank':bool, 'Init':io.addLogical}, 1552 'D' : {'Type':'Date', 'Retrieve':io.retrieveDate, 'Update':io.updateDate, 'Blank':Date.today, 'Init':io.addDate}, 1553 'M' : {'Type':'Memo', 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, 'Blank':str, 'Init':io.addVfpMemo}, 1554 'G' : {'Type':'General', 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, 'Blank':str, 'Init':io.addMemo}, 1555 'P' : {'Type':'Picture', 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, 'Blank':str, 'Init':io.addMemo}, 1556 '0' : {'Type':'_NullFlags', 'Retrieve':io.unsupportedType, 'Update':io.unsupportedType, 'Blank':int, 'Init':None} } 1557 _memoext = '.fpt' 1558 _memotypes = ('G','M','P') 1559 _memoClass = _VfpMemo 1560 _yesMemoMask = '\xf5' # 1111 0101 1561 _noMemoMask = '\x03' # 0000 0011 1562 _fixed_fields = ('B','D','G','I','L','M','P','T','Y') 1563 _variable_fields = ('C','F','N') 1564 _character_fields = ('C','M') # field representing character data 1565 _decimal_fields = ('F','N') 1566 _numeric_fields = ('B','F','I','N','Y') 1567 _supported_tables = ('\x03', '\xf5') 1568 _dbfTableHeader = array('c', '\x00' * 32) 1569 _dbfTableHeader[0] = '\x30' # version - Foxpro 6 0011 0000 1570 _dbfTableHeader[8:10] = array('c', io.packShortInt(33+263)) 1571 _dbfTableHeader[10] = '\x01' # record length -- one for delete flag 1572 _dbfTableHeader[29] = '\x03' # code page -- 437 US-MS DOS 1573 _dbfTableHeader = _dbfTableHeader.tostring() 1574 _dbfTableHeaderExtra = '\x00' * 263 1575 _use_deleted = True
1576 - def _checkMemoIntegrity(yo):
1577 if os.path.exists(yo._meta.memoname): 1578 try: 1579 yo._meta.memo = yo._memoClass(yo._meta) 1580 except: 1581 yo._meta.dfd.close() 1582 yo._meta.dfd = None 1583 raise 1584 if not yo._meta.ignorememos: 1585 for field in yo._meta.fields: 1586 if yo._meta[field]['type'] in yo._memotypes: 1587 if not os.path.exists(yo._meta.memoname): 1588 yo._meta.dfd.close() 1589 yo._meta.dfd = None 1590 raise DbfError("Table structure corrupt: memo fields exist without memo file") 1591 break
1592 - def _initializeFields(yo):
1593 "builds the FieldList of names, types, and descriptions" 1594 offset = 1 1595 fieldsdef = yo._meta.header.fields 1596 if len(fieldsdef) % 32 != 0: 1597 raise DbfError("field definition block corrupt: %d bytes in size" % len(fieldsdef)) 1598 if len(fieldsdef) // 32 != yo.field_count: 1599 raise DbfError("Header shows %d fields, but field definition block has %d fields" % (yo.field_count, len(fieldsdef)//32)) 1600 for i in range(yo.field_count): 1601 fieldblock = fieldsdef[i*32:(i+1)*32] 1602 name = io.unpackStr(fieldblock[:11]) 1603 type = fieldblock[11] 1604 if not type in yo._meta.fieldtypes: 1605 raise DbfError("Unknown field type: %s" % type) 1606 elif type == '0': 1607 return # ignore nullflags 1608 start = offset 1609 length = ord(fieldblock[16]) 1610 offset += length 1611 end = start + length 1612 decimals = ord(fieldblock[17]) 1613 flags = ord(fieldblock[18]) 1614 yo._meta.fields.append(name) 1615 yo._meta[name] = {'type':type,'start':start,'length':length,'end':end,'decimals':decimals,'flags':flags}
1616
1617 -class VfpTable(DbfTable):
1618 'Provides an interface for working with Visual FoxPro 6 tables' 1619 _version = 'Visual Foxpro v6' 1620 _versionabbv = 'vfp' 1621 _fieldtypes = { 1622 'C' : {'Type':'Character', 'Retrieve':io.retrieveCharacter, 'Update':io.updateCharacter, 'Blank':str, 'Init':io.addCharacter}, 1623 'Y' : {'Type':'Currency', 'Retrieve':io.retrieveCurrency, 'Update':io.updateCurrency, 'Blank':Decimal(), 'Init':io.addVfpCurrency}, 1624 'B' : {'Type':'Double', 'Retrieve':io.retrieveDouble, 'Update':io.updateDouble, 'Blank':float, 'Init':io.addVfpDouble}, 1625 'F' : {'Type':'Float', 'Retrieve':io.retrieveNumeric, 'Update':io.updateNumeric, 'Blank':float, 'Init':io.addVfpNumeric}, 1626 'N' : {'Type':'Numeric', 'Retrieve':io.retrieveNumeric, 'Update':io.updateNumeric, 'Blank':int, 'Init':io.addVfpNumeric}, 1627 'I' : {'Type':'Integer', 'Retrieve':io.retrieveInteger, 'Update':io.updateInteger, 'Blank':int, 'Init':io.addVfpInteger}, 1628 'L' : {'Type':'Logical', 'Retrieve':io.retrieveLogical, 'Update':io.updateLogical, 'Blank':bool, 'Init':io.addLogical}, 1629 'D' : {'Type':'Date', 'Retrieve':io.retrieveDate, 'Update':io.updateDate, 'Blank':Date.today, 'Init':io.addDate}, 1630 'T' : {'Type':'DateTime', 'Retrieve':io.retrieveVfpDateTime, 'Update':io.updateVfpDateTime, 'Blank':DateTime.now, 'Init':io.addVfpDateTime}, 1631 'M' : {'Type':'Memo', 'Retrieve':io.retrieveVfpMemo, 'Update':io.updateVfpMemo, 'Blank':str, 'Init':io.addVfpMemo}, 1632 'G' : {'Type':'General', 'Retrieve':io.retrieveVfpMemo, 'Update':io.updateVfpMemo, 'Blank':str, 'Init':io.addVfpMemo}, 1633 'P' : {'Type':'Picture', 'Retrieve':io.retrieveVfpMemo, 'Update':io.updateVfpMemo, 'Blank':str, 'Init':io.addVfpMemo}, 1634 '0' : {'Type':'_NullFlags', 'Retrieve':io.unsupportedType, 'Update':io.unsupportedType, 'Blank':int, 'Init':None} } 1635 _memoext = '.fpt' 1636 _memotypes = ('G','M','P') 1637 _memoClass = _VfpMemo 1638 _yesMemoMask = '\x30' # 0011 0000 1639 _noMemoMask = '\x30' # 0011 0000 1640 _fixed_fields = ('B','D','G','I','L','M','P','T','Y') 1641 _variable_fields = ('C','F','N') 1642 _character_fields = ('C','M') # field representing character data 1643 _decimal_fields = ('F','N') 1644 _numeric_fields = ('B','F','I','N','Y') 1645 _supported_tables = ('\x30',) 1646 _dbfTableHeader = array('c', '\x00' * 32) 1647 _dbfTableHeader[0] = '\x30' # version - Foxpro 6 0011 0000 1648 _dbfTableHeader[8:10] = array('c', io.packShortInt(33+263)) 1649 _dbfTableHeader[10] = '\x01' # record length -- one for delete flag 1650 _dbfTableHeader[29] = '\x03' # code page -- 437 US-MS DOS 1651 _dbfTableHeader = _dbfTableHeader.tostring() 1652 _dbfTableHeaderExtra = '\x00' * 263 1653 _use_deleted = True
1654 - def _checkMemoIntegrity(yo):
1655 if os.path.exists(yo._meta.memoname): 1656 try: 1657 yo._meta.memo = yo._memoClass(yo._meta) 1658 except: 1659 yo._meta.dfd.close() 1660 yo._meta.dfd = None 1661 raise 1662 if not yo._meta.ignorememos: 1663 for field in yo._meta.fields: 1664 if yo._meta[field]['type'] in yo._memotypes: 1665 if not os.path.exists(yo._meta.memoname): 1666 yo._meta.dfd.close() 1667 yo._meta.dfd = None 1668 raise DbfError("Table structure corrupt: memo fields exist without memo file") 1669 break
1670 - def _initializeFields(yo):
1671 "builds the FieldList of names, types, and descriptions" 1672 offset = 1 1673 fieldsdef = yo._meta.header.fields 1674 for i in range(yo.field_count): 1675 fieldblock = fieldsdef[i*32:(i+1)*32] 1676 name = io.unpackStr(fieldblock[:11]) 1677 type = fieldblock[11] 1678 if not type in yo._meta.fieldtypes: 1679 raise DbfError("Unknown field type: %s" % type) 1680 elif type == '0': 1681 return # ignore nullflags 1682 start = io.unpackLongInt(fieldblock[12:16]) 1683 length = ord(fieldblock[16]) 1684 offset += length 1685 end = start + length 1686 decimals = ord(fieldblock[17]) 1687 flags = ord(fieldblock[18]) 1688 yo._meta.fields.append(name) 1689 yo._meta[name] = {'type':type,'start':start,'length':length,'end':end,'decimals':decimals,'flags':flags}
1690 -class DbfList(object):
1691 "list of Dbf records, with set-like behavior" 1692 _desc = ''
1693 - def __init__(yo, new_records=None, desc=None):
1694 yo._list = [] 1695 yo._set = set() 1696 yo._current = -1 1697 if isinstance(new_records, DbfList): 1698 yo._list = new_records._list[:] 1699 yo._set = new_records._set.copy() 1700 yo._current = 0 1701 elif new_records is not None: 1702 for record in new_records: 1703 item = (record.record_table, record.record_number) 1704 if item not in yo._set: 1705 yo._set.add(item) 1706 yo._list.append(item) 1707 yo._current = 0 1708 if desc is not None: 1709 yo._desc = desc
1710 - def __add__(yo, other):
1711 if isinstance(other, DbfList): 1712 result = DbfList() 1713 result._set = yo._set.copy() 1714 result._list[:] = yo._list[:] 1715 for item in other._list: 1716 if item not in result._set: 1717 result._set.add(item) 1718 result._list.append(item) 1719 result._current = 0 if result else -1 1720 return result 1721 return NotImplemented
1722 - def __delitem__(yo, key):
1723 if isinstance(key, int): 1724 item = yo._list.pop[key] 1725 yo._set.remove(item) 1726 elif isinstance(key, slice): 1727 yo._set.difference_update(yo._list[key]) 1728 yo._list.__delitem__(key) 1729 else: 1730 raise TypeError
1731 - def __getitem__(yo, key):
1732 if isinstance(key, int): 1733 count = len(yo._list) 1734 if not -count <= key < count: 1735 raise IndexError("Record %d is not in list." % key) 1736 return yo._get_record(*yo._list[key]) 1737 elif isinstance(key, slice): 1738 result = DbfList() 1739 result._list[:] = yo._list[key] 1740 result._set = set(result._list) 1741 result._current = 0 if result else -1 1742 return result 1743 else: 1744 raise TypeError
1745 - def __iter__(yo):
1746 return (table.get_record(recno) for table, recno in yo._list)
1747 - def __len__(yo):
1748 return len(yo._list)
1749 - def __nonzero__(yo):
1750 return len(yo) > 0
1751 - def __radd__(yo, other):
1752 return yo.__add__(other)
1753 - def __repr__(yo):
1754 if yo._desc: 1755 return "DbfList(%s - %d records)" % (yo._desc, len(yo._list)) 1756 else: 1757 return "DbfList(%d records)" % len(yo._list)
1758 - def __rsub__(yo, other):
1759 if isinstance(other, DbfList): 1760 result = DbfList() 1761 result._list[:] = other._list[:] 1762 result._set = other._set.copy() 1763 lost = set() 1764 for item in yo._list: 1765 if item in result._list: 1766 result._set.remove(item) 1767 lost.add(item) 1768 result._list = [item for item in result._list if item not in lost] 1769 result._current = 0 if result else -1 1770 return result 1771 return NotImplemented
1772 - def __sub__(yo, other):
1773 if isinstance(other, DbfList): 1774 result = DbfList() 1775 result._list[:] = yo._list[:] 1776 result._set = yo._set.copy() 1777 lost = set() 1778 for item in other._list: 1779 if item in result._set: 1780 result._set.remove(item) 1781 lost.add(item) 1782 result._list = [item for item in result._list if item not in lost] 1783 result._current = 0 if result else -1 1784 return result 1785 return NotImplemented
1786 - def _maybe_add(yo, item):
1787 if item not in yo._set: 1788 yo._set.add(item) 1789 yo._list.append(item)
1790 - def _get_record(yo, table=None, rec_no=None):
1791 if table is rec_no is None: 1792 table, rec_no = yo._list[yo._current] 1793 return table.get_record(rec_no)
1794 - def append(yo, new_record):
1795 yo._maybe_add((new_record.record_table, new_record.record_number)) 1796 if yo._current == -1 and yo._list: 1797 yo._current = 0
1798 - def bottom(yo):
1799 if yo._list: 1800 yo._current = len(yo._list) - 1 1801 return yo._get_record() 1802 raise DbfError("DbfList is empty")
1803 - def clear(yo):
1804 yo._list = [] 1805 yo._set = set() 1806 yo._current = -1
1807 - def current(yo):
1808 if yo._current < 0: 1809 raise Bof() 1810 elif yo._current == len(yo._list): 1811 raise Eof() 1812 return yo._get_record()
1813 - def extend(yo, new_records):
1814 if isinstance(new_records, DbfList): 1815 for item in new_records._list: 1816 yo._maybe_add(item) 1817 else: 1818 for record in new_records: 1819 yo.append(record) 1820 if yo._current == -1 and yo._list: 1821 yo._current = 0
1822 - def goto(yo, index_number):
1823 if yo._list: 1824 if 0 <= index_number <= len(yo._list): 1825 yo._current = index_number 1826 return yo._get_record() 1827 raise DbfError("index %d not in DbfList of %d records" % (index_number, len(yo._list))) 1828 raise DbfError("DbfList is empty")
1829 - def insert(yo, i, table, record):
1830 item = table, record.record_number 1831 if item not in yo._set: 1832 yo._set.add(item) 1833 yo._list.insert(i, item)
1834 - def next(yo):
1835 if yo._current < len(yo._list): 1836 yo._current += 1 1837 if yo._current < len(yo._list): 1838 return yo._get_record() 1839 raise Eof()
1840 - def pop(yo, index=None):
1841 if index is None: 1842 table, recno = yo._list.pop() 1843 yo._set.remove((table, recno)) 1844 else: 1845 table, recno = yo._list.pop(index) 1846 yo._set.remove((table, recno)) 1847 return _get_record(table, recno)
1848 - def prev(yo):
1849 if yo._current >= 0: 1850 yo._current -= 1 1851 if yo._current > -1: 1852 return yo._get_record() 1853 raise Bof()
1854 - def remove(yo, record):
1855 item = record.record_table, record.record_number 1856 yo._list.remove(item) 1857 yo._set.remove(item)
1858 - def reverse(yo):
1859 return yo._list.reverse()
1860 - def top(yo):
1861 if yo._list: 1862 yo._current = 0 1863 return yo._get_record() 1864 raise DbfError("DbfList is empty")
1865 - def sort(yo, key=None, reverse=None):
1866 return yo._list.sort(key, reverse)
1867 -class DbfCsv(csv.Dialect):
1868 "csv format for exporting tables" 1869 delimiter = ',' 1870 doublequote = True 1871 escapechar = None 1872 lineterminator = '\r\n' 1873 quotechar = '"' 1874 skipinitialspace = True 1875 quoting = csv.QUOTE_NONNUMERIC
1876 csv.register_dialect('dbf', DbfCsv)
1877 1878 -def _nop(value):
1879 "returns parameter unchanged" 1880 return value
1881 -def _normalize_tuples(tuples, length, filler):
1882 "ensures each tuple is the same length, using filler[-missing] for the gaps" 1883 final = [] 1884 for t in tuples: 1885 if len(t) < length: 1886 final.append( tuple([item for item in t] + filler[len(t)-length:]) ) 1887 else: 1888 final.append(t) 1889 return tuple(final)
1890 -def _codepage_lookup(cp):
1891 if cp not in code_pages: 1892 for code_page in sorted(code_pages.keys()): 1893 sd, ld = code_pages[code_page] 1894 if cp == sd or cp == ld: 1895 if sd is None: 1896 raise DbfError("Unsupported codepage: %s" % ld) 1897 cp = code_page 1898 break 1899 else: 1900 raise DbfError("Unsupported codepage: %s" % cp) 1901 sd, ld = code_pages[cp] 1902 return cp, sd, ld
1903 -def ascii(new_setting=None):
1904 "get/set return_ascii setting" 1905 global return_ascii 1906 if new_setting is None: 1907 return return_ascii 1908 else: 1909 return_ascii = new_setting
1910 -def codepage(cp=None):
1911 "get/set default codepage for any new tables" 1912 global default_codepage 1913 cp, sd, ld = _codepage_lookup(cp or default_codepage) 1914 default_codepage = sd 1915 return "%s (LDID: 0x%02x - %s)" % (sd, ord(cp), ld)
1916 -def encoding(cp=None):
1917 "get/set default encoding for non-unicode strings passed into a table" 1918 global input_decoding 1919 cp, sd, ld = _codepage_lookup(cp or input_decoding) 1920 default_codepage = sd 1921 return "%s (LDID: 0x%02x - %s)" % (sd, ord(cp), ld)
1922 -class _Db4Table(DbfTable):
1923 version = 'dBase IV w/memos (non-functional)' 1924 _versionabbv = 'db4' 1925 _fieldtypes = { 1926 'C' : {'Type':'Character', 'Retrieve':io.retrieveCharacter, 'Update':io.updateCharacter, 'Blank':str, 'Init':io.addCharacter}, 1927 'Y' : {'Type':'Currency', 'Retrieve':io.retrieveCurrency, 'Update':io.updateCurrency, 'Blank':Decimal(), 'Init':io.addVfpCurrency}, 1928 'B' : {'Type':'Double', 'Retrieve':io.retrieveDouble, 'Update':io.updateDouble, 'Blank':float, 'Init':io.addVfpDouble}, 1929 'F' : {'Type':'Float', 'Retrieve':io.retrieveNumeric, 'Update':io.updateNumeric, 'Blank':float, 'Init':io.addVfpNumeric}, 1930 'N' : {'Type':'Numeric', 'Retrieve':io.retrieveNumeric, 'Update':io.updateNumeric, 'Blank':int, 'Init':io.addVfpNumeric}, 1931 'I' : {'Type':'Integer', 'Retrieve':io.retrieveInteger, 'Update':io.updateInteger, 'Blank':int, 'Init':io.addVfpInteger}, 1932 'L' : {'Type':'Logical', 'Retrieve':io.retrieveLogical, 'Update':io.updateLogical, 'Blank':bool, 'Init':io.addLogical}, 1933 'D' : {'Type':'Date', 'Retrieve':io.retrieveDate, 'Update':io.updateDate, 'Blank':Date.today, 'Init':io.addDate}, 1934 'T' : {'Type':'DateTime', 'Retrieve':io.retrieveVfpDateTime, 'Update':io.updateVfpDateTime, 'Blank':DateTime.now, 'Init':io.addVfpDateTime}, 1935 'M' : {'Type':'Memo', 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, 'Blank':str, 'Init':io.addMemo}, 1936 'G' : {'Type':'General', 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, 'Blank':str, 'Init':io.addMemo}, 1937 'P' : {'Type':'Picture', 'Retrieve':io.retrieveMemo, 'Update':io.updateMemo, 'Blank':str, 'Init':io.addMemo}, 1938 '0' : {'Type':'_NullFlags', 'Retrieve':io.unsupportedType, 'Update':io.unsupportedType, 'Blank':int, 'Init':None} } 1939 _memoext = '.dbt' 1940 _memotypes = ('G','M','P') 1941 _memoClass = _VfpMemo 1942 _yesMemoMask = '\x8b' # 0011 0000 1943 _noMemoMask = '\x04' # 0011 0000 1944 _fixed_fields = ('B','D','G','I','L','M','P','T','Y') 1945 _variable_fields = ('C','F','N') 1946 _character_fields = ('C','M') # field representing character data 1947 _decimal_fields = ('F','N') 1948 _numeric_fields = ('B','F','I','N','Y') 1949 _supported_tables = ('\x04', '\x8b') 1950 _dbfTableHeader = ['\x00'] * 32 1951 _dbfTableHeader[0] = '\x8b' # version - Foxpro 6 0011 0000 1952 _dbfTableHeader[10] = '\x01' # record length -- one for delete flag 1953 _dbfTableHeader[29] = '\x03' # code page -- 437 US-MS DOS 1954 _dbfTableHeader = ''.join(_dbfTableHeader) 1955 _dbfTableHeaderExtra = '' 1956 _use_deleted = True
1957 - def _checkMemoIntegrity(yo):
1958 "dBase III specific" 1959 if yo._meta.header.version == '\x8b': 1960 try: 1961 yo._meta.memo = yo._memoClass(yo._meta) 1962 except: 1963 yo._meta.dfd.close() 1964 yo._meta.dfd = None 1965 raise 1966 if not yo._meta.ignorememos: 1967 for field in yo._meta.fields: 1968 if yo._meta[field]['type'] in yo._memotypes: 1969 if yo._meta.header.version != '\x8b': 1970 yo._meta.dfd.close() 1971 yo._meta.dfd = None 1972 raise DbfError("Table structure corrupt: memo fields exist, header declares no memos") 1973 elif not os.path.exists(yo._meta.memoname): 1974 yo._meta.dfd.close() 1975 yo._meta.dfd = None 1976 raise DbfError("Table structure corrupt: memo fields exist without memo file") 1977 break
1978