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|
#
# (re)generate unicode property and type databases
#
# this script converts a unicode 3.2 database file to
# Modules/unicodedata_db.h, Modules/unicodename_db.h,
# and Objects/unicodetype_db.h
#
# history:
# 2000-09-24 fl created (based on bits and pieces from unidb)
# 2000-09-25 fl merged tim's splitbin fixes, separate decomposition table
# 2000-09-25 fl added character type table
# 2000-09-26 fl added LINEBREAK, DECIMAL, and DIGIT flags/fields (2.0)
# 2000-11-03 fl expand first/last ranges
# 2001-01-19 fl added character name tables (2.1)
# 2001-01-21 fl added decomp compression; dynamic phrasebook threshold
# 2002-09-11 wd use string methods
# 2002-10-18 mvl update to Unicode 3.2
# 2002-10-22 mvl generate NFC tables
# 2002-11-24 mvl expand all ranges, sort names version-independently
# 2002-11-25 mvl add UNIDATA_VERSION
#
# written by Fredrik Lundh (fredrik@pythonware.com)
#
import sys
SCRIPT = sys.argv[0]
VERSION = "2.2"
# The Unicode Database
UNIDATA_VERSION = "3.2.0"
UNICODE_DATA = "UnicodeData.txt"
COMPOSITION_EXCLUSIONS = "CompositionExclusions.txt"
CATEGORY_NAMES = [ "Cn", "Lu", "Ll", "Lt", "Mn", "Mc", "Me", "Nd",
"Nl", "No", "Zs", "Zl", "Zp", "Cc", "Cf", "Cs", "Co", "Cn", "Lm",
"Lo", "Pc", "Pd", "Ps", "Pe", "Pi", "Pf", "Po", "Sm", "Sc", "Sk",
"So" ]
BIDIRECTIONAL_NAMES = [ "", "L", "LRE", "LRO", "R", "AL", "RLE", "RLO",
"PDF", "EN", "ES", "ET", "AN", "CS", "NSM", "BN", "B", "S", "WS",
"ON" ]
# note: should match definitions in Objects/unicodectype.c
ALPHA_MASK = 0x01
DECIMAL_MASK = 0x02
DIGIT_MASK = 0x04
LOWER_MASK = 0x08
LINEBREAK_MASK = 0x10
SPACE_MASK = 0x20
TITLE_MASK = 0x40
UPPER_MASK = 0x80
def maketables(trace=0):
print "--- Reading", UNICODE_DATA, "..."
unicode = UnicodeData(UNICODE_DATA, COMPOSITION_EXCLUSIONS)
print len(filter(None, unicode.table)), "characters"
makeunicodename(unicode, trace)
makeunicodedata(unicode, trace)
makeunicodetype(unicode, trace)
# --------------------------------------------------------------------
# unicode character properties
def makeunicodedata(unicode, trace):
dummy = (0, 0, 0, 0)
table = [dummy]
cache = {0: dummy}
index = [0] * len(unicode.chars)
FILE = "Modules/unicodedata_db.h"
print "--- Preparing", FILE, "..."
# 1) database properties
for char in unicode.chars:
record = unicode.table[char]
if record:
# extract database properties
category = CATEGORY_NAMES.index(record[2])
combining = int(record[3])
bidirectional = BIDIRECTIONAL_NAMES.index(record[4])
mirrored = record[9] == "Y"
item = (
category, combining, bidirectional, mirrored
)
# add entry to index and item tables
i = cache.get(item)
if i is None:
cache[item] = i = len(table)
table.append(item)
index[char] = i
# 2) decomposition data
decomp_data = [0]
decomp_prefix = [""]
decomp_index = [0] * len(unicode.chars)
decomp_size = 0
comp_pairs = []
comp_first = [None] * len(unicode.chars)
comp_last = [None] * len(unicode.chars)
for char in unicode.chars:
record = unicode.table[char]
if record:
if record[5]:
decomp = record[5].split()
# prefix
if decomp[0][0] == "<":
prefix = decomp.pop(0)
else:
prefix = ""
try:
i = decomp_prefix.index(prefix)
except ValueError:
i = len(decomp_prefix)
decomp_prefix.append(prefix)
prefix = i
assert prefix < 256
# content
decomp = [prefix + (len(decomp)<<8)] +\
map(lambda s: int(s, 16), decomp)
# Collect NFC pairs
if not prefix and len(decomp) == 3 and \
char not in unicode.exclusions and \
unicode.table[decomp[1]][3] == "0":
p, l, r = decomp
comp_first[l] = 1
comp_last[r] = 1
comp_pairs.append((l,r,char))
try:
i = decomp_data.index(decomp)
except ValueError:
i = len(decomp_data)
decomp_data.extend(decomp)
decomp_size = decomp_size + len(decomp) * 2
else:
i = 0
decomp_index[char] = i
f = l = 0
comp_first_ranges = []
comp_last_ranges = []
prev_f = prev_l = None
for i in unicode.chars:
if comp_first[i] is not None:
comp_first[i] = f
f += 1
if prev_f is None:
prev_f = (i,i)
elif prev_f[1]+1 == i:
prev_f = prev_f[0],i
else:
comp_first_ranges.append(prev_f)
prev_f = (i,i)
if comp_last[i] is not None:
comp_last[i] = l
l += 1
if prev_l is None:
prev_l = (i,i)
elif prev_l[1]+1 == i:
prev_l = prev_l[0],i
else:
comp_last_ranges.append(prev_l)
prev_l = (i,i)
comp_first_ranges.append(prev_f)
comp_last_ranges.append(prev_l)
total_first = f
total_last = l
comp_data = [0]*(total_first*total_last)
for f,l,char in comp_pairs:
f = comp_first[f]
l = comp_last[l]
comp_data[f*total_last+l] = char
print len(table), "unique properties"
print len(decomp_prefix), "unique decomposition prefixes"
print len(decomp_data), "unique decomposition entries:",
print decomp_size, "bytes"
print total_first, "first characters in NFC"
print total_last, "last characters in NFC"
print len(comp_pairs), "NFC pairs"
print "--- Writing", FILE, "..."
fp = open(FILE, "w")
print >>fp, "/* this file was generated by %s %s */" % (SCRIPT, VERSION)
print >>fp
print >>fp, '#define UNIDATA_VERSION "%s"' % UNIDATA_VERSION
print >>fp, "/* a list of unique database records */"
print >>fp, \
"const _PyUnicode_DatabaseRecord _PyUnicode_Database_Records[] = {"
for item in table:
print >>fp, " {%d, %d, %d, %d}," % item
print >>fp, "};"
print >>fp
print >>fp, "/* Reindexing of NFC first characters. */"
print >>fp, "#define TOTAL_FIRST",total_first
print >>fp, "#define TOTAL_LAST",total_last
print >>fp, "struct reindex{int start;short count,index;};"
print >>fp, "struct reindex nfc_first[] = {"
for start,end in comp_first_ranges:
print >>fp," { %d, %d, %d}," % (start,end-start,comp_first[start])
print >>fp," {0,0,0}"
print >>fp,"};\n"
print >>fp, "struct reindex nfc_last[] = {"
for start,end in comp_last_ranges:
print >>fp," { %d, %d, %d}," % (start,end-start,comp_last[start])
print >>fp," {0,0,0}"
print >>fp,"};\n"
# FIXME: <fl> the following tables could be made static, and
# the support code moved into unicodedatabase.c
print >>fp, "/* string literals */"
print >>fp, "const char *_PyUnicode_CategoryNames[] = {"
for name in CATEGORY_NAMES:
print >>fp, " \"%s\"," % name
print >>fp, " NULL"
print >>fp, "};"
print >>fp, "const char *_PyUnicode_BidirectionalNames[] = {"
for name in BIDIRECTIONAL_NAMES:
print >>fp, " \"%s\"," % name
print >>fp, " NULL"
print >>fp, "};"
print >>fp, "static const char *decomp_prefix[] = {"
for name in decomp_prefix:
print >>fp, " \"%s\"," % name
print >>fp, " NULL"
print >>fp, "};"
# split record index table
index1, index2, shift = splitbins(index, trace)
print >>fp, "/* index tables for the database records */"
print >>fp, "#define SHIFT", shift
Array("index1", index1).dump(fp, trace)
Array("index2", index2).dump(fp, trace)
# split decomposition index table
index1, index2, shift = splitbins(decomp_index, trace)
print >>fp, "/* decomposition data */"
Array("decomp_data", decomp_data).dump(fp, trace)
print >>fp, "/* index tables for the decomposition data */"
print >>fp, "#define DECOMP_SHIFT", shift
Array("decomp_index1", index1).dump(fp, trace)
Array("decomp_index2", index2).dump(fp, trace)
index, index2, shift = splitbins(comp_data, trace)
print >>fp, "/* NFC pairs */"
print >>fp, "#define COMP_SHIFT", shift
Array("comp_index", index).dump(fp, trace)
Array("comp_data", index2).dump(fp, trace)
fp.close()
# --------------------------------------------------------------------
# unicode character type tables
def makeunicodetype(unicode, trace):
FILE = "Objects/unicodetype_db.h"
print "--- Preparing", FILE, "..."
# extract unicode types
dummy = (0, 0, 0, 0, 0, 0)
table = [dummy]
cache = {0: dummy}
index = [0] * len(unicode.chars)
for char in unicode.chars:
record = unicode.table[char]
if record:
# extract database properties
category = record[2]
bidirectional = record[4]
flags = 0
if category in ["Lm", "Lt", "Lu", "Ll", "Lo"]:
flags |= ALPHA_MASK
if category == "Ll":
flags |= LOWER_MASK
if category == "Zl" or bidirectional == "B":
flags |= LINEBREAK_MASK
if category == "Zs" or bidirectional in ("WS", "B", "S"):
flags |= SPACE_MASK
if category == "Lt":
flags |= TITLE_MASK
if category == "Lu":
flags |= UPPER_MASK
# use delta predictor for upper/lower/title
if record[12]:
upper = int(record[12], 16) - char
assert -32768 <= upper <= 32767
upper = upper & 0xffff
else:
upper = 0
if record[13]:
lower = int(record[13], 16) - char
assert -32768 <= lower <= 32767
lower = lower & 0xffff
else:
lower = 0
if record[14]:
title = int(record[14], 16) - char
assert -32768 <= lower <= 32767
title = title & 0xffff
else:
title = 0
# decimal digit, integer digit
decimal = 0
if record[6]:
flags |= DECIMAL_MASK
decimal = int(record[6])
digit = 0
if record[7]:
flags |= DIGIT_MASK
digit = int(record[7])
item = (
flags, upper, lower, title, decimal, digit
)
# add entry to index and item tables
i = cache.get(item)
if i is None:
cache[item] = i = len(table)
table.append(item)
index[char] = i
print len(table), "unique character type entries"
print "--- Writing", FILE, "..."
fp = open(FILE, "w")
print >>fp, "/* this file was generated by %s %s */" % (SCRIPT, VERSION)
print >>fp
print >>fp, "/* a list of unique character type descriptors */"
print >>fp, "const _PyUnicode_TypeRecord _PyUnicode_TypeRecords[] = {"
for item in table:
print >>fp, " {%d, %d, %d, %d, %d, %d}," % item
print >>fp, "};"
print >>fp
# split decomposition index table
index1, index2, shift = splitbins(index, trace)
print >>fp, "/* type indexes */"
print >>fp, "#define SHIFT", shift
Array("index1", index1).dump(fp, trace)
Array("index2", index2).dump(fp, trace)
fp.close()
# --------------------------------------------------------------------
# unicode name database
def makeunicodename(unicode, trace):
FILE = "Modules/unicodename_db.h"
print "--- Preparing", FILE, "..."
# collect names
names = [None] * len(unicode.chars)
for char in unicode.chars:
record = unicode.table[char]
if record:
name = record[1].strip()
if name and name[0] != "<":
names[char] = name + chr(0)
print len(filter(lambda n: n is not None, names)), "distinct names"
# collect unique words from names (note that we differ between
# words inside a sentence, and words ending a sentence. the
# latter includes the trailing null byte.
words = {}
n = b = 0
for char in unicode.chars:
name = names[char]
if name:
w = name.split()
b = b + len(name)
n = n + len(w)
for w in w:
l = words.get(w)
if l:
l.append(None)
else:
words[w] = [len(words)]
print n, "words in text;", b, "bytes"
wordlist = words.items()
# sort on falling frequency, then by name
def cmpwords((aword, alist),(bword, blist)):
r = -cmp(len(alist),len(blist))
if r:
return r
return cmp(aword, bword)
wordlist.sort(cmpwords)
# figure out how many phrasebook escapes we need
escapes = 0
while escapes * 256 < len(wordlist):
escapes = escapes + 1
print escapes, "escapes"
short = 256 - escapes
assert short > 0
print short, "short indexes in lexicon"
# statistics
n = 0
for i in range(short):
n = n + len(wordlist[i][1])
print n, "short indexes in phrasebook"
# pick the most commonly used words, and sort the rest on falling
# length (to maximize overlap)
wordlist, wordtail = wordlist[:short], wordlist[short:]
wordtail.sort(lambda a, b: len(b[0])-len(a[0]))
wordlist.extend(wordtail)
# generate lexicon from words
lexicon_offset = [0]
lexicon = ""
words = {}
# build a lexicon string
offset = 0
for w, x in wordlist:
# encoding: bit 7 indicates last character in word (chr(128)
# indicates the last character in an entire string)
ww = w[:-1] + chr(ord(w[-1])+128)
# reuse string tails, when possible
o = lexicon.find(ww)
if o < 0:
o = offset
lexicon = lexicon + ww
offset = offset + len(w)
words[w] = len(lexicon_offset)
lexicon_offset.append(o)
lexicon = map(ord, lexicon)
# generate phrasebook from names and lexicon
phrasebook = [0]
phrasebook_offset = [0] * len(unicode.chars)
for char in unicode.chars:
name = names[char]
if name:
w = name.split()
phrasebook_offset[char] = len(phrasebook)
for w in w:
i = words[w]
if i < short:
phrasebook.append(i)
else:
# store as two bytes
phrasebook.append((i>>8) + short)
phrasebook.append(i&255)
assert getsize(phrasebook) == 1
#
# unicode name hash table
# extract names
data = []
for char in unicode.chars:
record = unicode.table[char]
if record:
name = record[1].strip()
if name and name[0] != "<":
data.append((name, char))
# the magic number 47 was chosen to minimize the number of
# collisions on the current data set. if you like, change it
# and see what happens...
codehash = Hash("code", data, 47)
print "--- Writing", FILE, "..."
fp = open(FILE, "w")
print >>fp, "/* this file was generated by %s %s */" % (SCRIPT, VERSION)
print >>fp
print >>fp, "#define NAME_MAXLEN", 256
print >>fp
print >>fp, "/* lexicon */"
Array("lexicon", lexicon).dump(fp, trace)
Array("lexicon_offset", lexicon_offset).dump(fp, trace)
# split decomposition index table
offset1, offset2, shift = splitbins(phrasebook_offset, trace)
print >>fp, "/* code->name phrasebook */"
print >>fp, "#define phrasebook_shift", shift
print >>fp, "#define phrasebook_short", short
Array("phrasebook", phrasebook).dump(fp, trace)
Array("phrasebook_offset1", offset1).dump(fp, trace)
Array("phrasebook_offset2", offset2).dump(fp, trace)
print >>fp, "/* name->code dictionary */"
codehash.dump(fp, trace)
fp.close()
# --------------------------------------------------------------------
# the following support code is taken from the unidb utilities
# Copyright (c) 1999-2000 by Secret Labs AB
# load a unicode-data file from disk
import sys
class UnicodeData:
def __init__(self, filename, exclusions, expand=1):
file = open(filename)
table = [None] * 0x110000
while 1:
s = file.readline()
if not s:
break
s = s.strip().split(";")
char = int(s[0], 16)
table[char] = s
# expand first-last ranges
if expand:
field = None
for i in range(0, 0x110000):
s = table[i]
if s:
if s[1][-6:] == "First>":
s[1] = ""
field = s[:]
elif s[1][-5:] == "Last>":
s[1] = ""
field = None
elif field:
field[0] = hex(i)
table[i] = field
# public attributes
self.filename = filename
self.table = table
self.chars = range(0x110000) # unicode 3.2
file = open(exclusions)
self.exclusions = {}
for s in file:
s = s.strip()
if not s:
continue
if s[0] == '#':
continue
char = int(s.split()[0],16)
self.exclusions[char] = 1
def uselatin1(self):
# restrict character range to ISO Latin 1
self.chars = range(256)
# hash table tools
# this is a straight-forward reimplementation of Python's built-in
# dictionary type, using a static data structure, and a custom string
# hash algorithm.
def myhash(s, magic):
h = 0
for c in map(ord, s.upper()):
h = (h * magic) + c
ix = h & 0xff000000L
if ix:
h = (h ^ ((ix>>24) & 0xff)) & 0x00ffffff
return h
SIZES = [
(4,3), (8,3), (16,3), (32,5), (64,3), (128,3), (256,29), (512,17),
(1024,9), (2048,5), (4096,83), (8192,27), (16384,43), (32768,3),
(65536,45), (131072,9), (262144,39), (524288,39), (1048576,9),
(2097152,5), (4194304,3), (8388608,33), (16777216,27)
]
class Hash:
def __init__(self, name, data, magic):
# turn a (key, value) list into a static hash table structure
# determine table size
for size, poly in SIZES:
if size > len(data):
poly = size + poly
break
else:
raise AssertionError, "ran out of polynominals"
print size, "slots in hash table"
table = [None] * size
mask = size-1
n = 0
hash = myhash
# initialize hash table
for key, value in data:
h = hash(key, magic)
i = (~h) & mask
v = table[i]
if v is None:
table[i] = value
continue
incr = (h ^ (h >> 3)) & mask;
if not incr:
incr = mask
while 1:
n = n + 1
i = (i + incr) & mask
v = table[i]
if v is None:
table[i] = value
break
incr = incr << 1
if incr > mask:
incr = incr ^ poly
print n, "collisions"
self.collisions = n
for i in range(len(table)):
if table[i] is None:
table[i] = 0
self.data = Array(name + "_hash", table)
self.magic = magic
self.name = name
self.size = size
self.poly = poly
def dump(self, file, trace):
# write data to file, as a C array
self.data.dump(file, trace)
file.write("#define %s_magic %d\n" % (self.name, self.magic))
file.write("#define %s_size %d\n" % (self.name, self.size))
file.write("#define %s_poly %d\n" % (self.name, self.poly))
# stuff to deal with arrays of unsigned integers
class Array:
def __init__(self, name, data):
self.name = name
self.data = data
def dump(self, file, trace=0):
# write data to file, as a C array
size = getsize(self.data)
if trace:
print >>sys.stderr, self.name+":", size*len(self.data), "bytes"
file.write("static ")
if size == 1:
file.write("unsigned char")
elif size == 2:
file.write("unsigned short")
else:
file.write("unsigned int")
file.write(" " + self.name + "[] = {\n")
if self.data:
s = " "
for item in self.data:
i = str(item) + ", "
if len(s) + len(i) > 78:
file.write(s + "\n")
s = " " + i
else:
s = s + i
if s.strip():
file.write(s + "\n")
file.write("};\n\n")
def getsize(data):
# return smallest possible integer size for the given array
maxdata = max(data)
if maxdata < 256:
return 1
elif maxdata < 65536:
return 2
else:
return 4
def splitbins(t, trace=0):
"""t, trace=0 -> (t1, t2, shift). Split a table to save space.
t is a sequence of ints. This function can be useful to save space if
many of the ints are the same. t1 and t2 are lists of ints, and shift
is an int, chosen to minimize the combined size of t1 and t2 (in C
code), and where for each i in range(len(t)),
t[i] == t2[(t1[i >> shift] << shift) + (i & mask)]
where mask is a bitmask isolating the last "shift" bits.
If optional arg trace is non-zero (default zero), progress info
is printed to sys.stderr. The higher the value, the more info
you'll get.
"""
import sys
if trace:
def dump(t1, t2, shift, bytes):
print >>sys.stderr, "%d+%d bins at shift %d; %d bytes" % (
len(t1), len(t2), shift, bytes)
print >>sys.stderr, "Size of original table:", len(t)*getsize(t), \
"bytes"
n = len(t)-1 # last valid index
maxshift = 0 # the most we can shift n and still have something left
if n > 0:
while n >> 1:
n >>= 1
maxshift += 1
del n
bytes = sys.maxint # smallest total size so far
t = tuple(t) # so slices can be dict keys
for shift in range(maxshift + 1):
t1 = []
t2 = []
size = 2**shift
bincache = {}
for i in range(0, len(t), size):
bin = t[i:i+size]
index = bincache.get(bin)
if index is None:
index = len(t2)
bincache[bin] = index
t2.extend(bin)
t1.append(index >> shift)
# determine memory size
b = len(t1)*getsize(t1) + len(t2)*getsize(t2)
if trace > 1:
dump(t1, t2, shift, b)
if b < bytes:
best = t1, t2, shift
bytes = b
t1, t2, shift = best
if trace:
print >>sys.stderr, "Best:",
dump(t1, t2, shift, bytes)
if __debug__:
# exhaustively verify that the decomposition is correct
mask = ~((~0) << shift) # i.e., low-bit mask of shift bits
for i in xrange(len(t)):
assert t[i] == t2[(t1[i >> shift] << shift) + (i & mask)]
return best
if __name__ == "__main__":
maketables(1)
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