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This file contains ambiguous Unicode characters!

This file contains ambiguous Unicode characters that may be confused with others in your current locale. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to highlight these characters.

#
# Secret Labs' Regular Expression Engine
#
# convert template to internal format
#
# Copyright (c) 1997-2001 by Secret Labs AB. All rights reserved.
#
# See the sre.py file for information on usage and redistribution.
#
"""Internal support module for sre"""
import _sre
import sre_parse
from sre_constants import *
assert _sre.MAGIC == MAGIC, "SRE module mismatch"
_LITERAL_CODES = {LITERAL, NOT_LITERAL}
_REPEATING_CODES = {REPEAT, MIN_REPEAT, MAX_REPEAT}
_SUCCESS_CODES = {SUCCESS, FAILURE}
_ASSERT_CODES = {ASSERT, ASSERT_NOT}
_UNIT_CODES = _LITERAL_CODES | {ANY, IN}
# Sets of lowercase characters which have the same uppercase.
_equivalences = (
# LATIN SMALL LETTER I, LATIN SMALL LETTER DOTLESS I
(0x69, 0x131), # iı
# LATIN SMALL LETTER S, LATIN SMALL LETTER LONG S
(0x73, 0x17f), # sſ
# MICRO SIGN, GREEK SMALL LETTER MU
(0xb5, 0x3bc), # µμ
# COMBINING GREEK YPOGEGRAMMENI, GREEK SMALL LETTER IOTA, GREEK PROSGEGRAMMENI
(0x345, 0x3b9, 0x1fbe), # \u0345ι
# GREEK SMALL LETTER IOTA WITH DIALYTIKA AND TONOS, GREEK SMALL LETTER IOTA WITH DIALYTIKA AND OXIA
(0x390, 0x1fd3), # ΐΐ
# GREEK SMALL LETTER UPSILON WITH DIALYTIKA AND TONOS, GREEK SMALL LETTER UPSILON WITH DIALYTIKA AND OXIA
(0x3b0, 0x1fe3), # ΰΰ
# GREEK SMALL LETTER BETA, GREEK BETA SYMBOL
(0x3b2, 0x3d0), # βϐ
# GREEK SMALL LETTER EPSILON, GREEK LUNATE EPSILON SYMBOL
(0x3b5, 0x3f5), # εϵ
# GREEK SMALL LETTER THETA, GREEK THETA SYMBOL
(0x3b8, 0x3d1), # θϑ
# GREEK SMALL LETTER KAPPA, GREEK KAPPA SYMBOL
(0x3ba, 0x3f0), # κϰ
# GREEK SMALL LETTER PI, GREEK PI SYMBOL
(0x3c0, 0x3d6), # πϖ
# GREEK SMALL LETTER RHO, GREEK RHO SYMBOL
(0x3c1, 0x3f1), # ρϱ
# GREEK SMALL LETTER FINAL SIGMA, GREEK SMALL LETTER SIGMA
(0x3c2, 0x3c3), # ςσ
# GREEK SMALL LETTER PHI, GREEK PHI SYMBOL
(0x3c6, 0x3d5), # φϕ
# LATIN SMALL LETTER S WITH DOT ABOVE, LATIN SMALL LETTER LONG S WITH DOT ABOVE
(0x1e61, 0x1e9b), # ṡẛ
# LATIN SMALL LIGATURE LONG S T, LATIN SMALL LIGATURE ST
(0xfb05, 0xfb06), # ſtst
)
# Maps the lowercase code to lowercase codes which have the same uppercase.
_ignorecase_fixes = {i: tuple(j for j in t if i != j)
for t in _equivalences for i in t}
def _combine_flags(flags, add_flags, del_flags,
TYPE_FLAGS=sre_parse.TYPE_FLAGS):
if add_flags & TYPE_FLAGS:
flags &= ~TYPE_FLAGS
return (flags | add_flags) & ~del_flags
def _compile(code, pattern, flags):
# internal: compile a (sub)pattern
emit = code.append
_len = len
LITERAL_CODES = _LITERAL_CODES
REPEATING_CODES = _REPEATING_CODES
SUCCESS_CODES = _SUCCESS_CODES
ASSERT_CODES = _ASSERT_CODES
iscased = None
tolower = None
fixes = None
if flags & SRE_FLAG_IGNORECASE and not flags & SRE_FLAG_LOCALE:
if flags & SRE_FLAG_UNICODE:
iscased = _sre.unicode_iscased
tolower = _sre.unicode_tolower
fixes = _ignorecase_fixes
else:
iscased = _sre.ascii_iscased
tolower = _sre.ascii_tolower
for op, av in pattern:
if op in LITERAL_CODES:
if not flags & SRE_FLAG_IGNORECASE:
emit(op)
emit(av)
elif flags & SRE_FLAG_LOCALE:
emit(OP_LOCALE_IGNORE[op])
emit(av)
elif not iscased(av):
emit(op)
emit(av)
else:
lo = tolower(av)
if not fixes: # ascii
emit(OP_IGNORE[op])
emit(lo)
elif lo not in fixes:
emit(OP_UNICODE_IGNORE[op])
emit(lo)
else:
emit(IN_UNI_IGNORE)
skip = _len(code); emit(0)
if op is NOT_LITERAL:
emit(NEGATE)
for k in (lo,) + fixes[lo]:
emit(LITERAL)
emit(k)
emit(FAILURE)
code[skip] = _len(code) - skip
elif op is IN:
charset, hascased = _optimize_charset(av, iscased, tolower, fixes)
if flags & SRE_FLAG_IGNORECASE and flags & SRE_FLAG_LOCALE:
emit(IN_LOC_IGNORE)
elif not hascased:
emit(IN)
elif not fixes: # ascii
emit(IN_IGNORE)
else:
emit(IN_UNI_IGNORE)
skip = _len(code); emit(0)
_compile_charset(charset, flags, code)
code[skip] = _len(code) - skip
elif op is ANY:
if flags & SRE_FLAG_DOTALL:
emit(ANY_ALL)
else:
emit(ANY)
elif op in REPEATING_CODES:
if flags & SRE_FLAG_TEMPLATE:
raise error("internal: unsupported template operator %r" % (op,))
if _simple(av[2]):
if op is MAX_REPEAT:
emit(REPEAT_ONE)
else:
emit(MIN_REPEAT_ONE)
skip = _len(code); emit(0)
emit(av[0])
emit(av[1])
_compile(code, av[2], flags)
emit(SUCCESS)
code[skip] = _len(code) - skip
else:
emit(REPEAT)
skip = _len(code); emit(0)
emit(av[0])
emit(av[1])
_compile(code, av[2], flags)
code[skip] = _len(code) - skip
if op is MAX_REPEAT:
emit(MAX_UNTIL)
else:
emit(MIN_UNTIL)
elif op is SUBPATTERN:
group, add_flags, del_flags, p = av
if group:
emit(MARK)
emit((group-1)*2)
# _compile_info(code, p, _combine_flags(flags, add_flags, del_flags))
_compile(code, p, _combine_flags(flags, add_flags, del_flags))
if group:
emit(MARK)
emit((group-1)*2+1)
elif op in SUCCESS_CODES:
emit(op)
elif op in ASSERT_CODES:
emit(op)
skip = _len(code); emit(0)
if av[0] >= 0:
emit(0) # look ahead
else:
lo, hi = av[1].getwidth()
if lo != hi:
raise error("look-behind requires fixed-width pattern")
emit(lo) # look behind
_compile(code, av[1], flags)
emit(SUCCESS)
code[skip] = _len(code) - skip
elif op is CALL:
emit(op)
skip = _len(code); emit(0)
_compile(code, av, flags)
emit(SUCCESS)
code[skip] = _len(code) - skip
elif op is AT:
emit(op)
if flags & SRE_FLAG_MULTILINE:
av = AT_MULTILINE.get(av, av)
if flags & SRE_FLAG_LOCALE:
av = AT_LOCALE.get(av, av)
elif flags & SRE_FLAG_UNICODE:
av = AT_UNICODE.get(av, av)
emit(av)
elif op is BRANCH:
emit(op)
tail = []
tailappend = tail.append
for av in av[1]:
skip = _len(code); emit(0)
# _compile_info(code, av, flags)
_compile(code, av, flags)
emit(JUMP)
tailappend(_len(code)); emit(0)
code[skip] = _len(code) - skip
emit(FAILURE) # end of branch
for tail in tail:
code[tail] = _len(code) - tail
elif op is CATEGORY:
emit(op)
if flags & SRE_FLAG_LOCALE:
av = CH_LOCALE[av]
elif flags & SRE_FLAG_UNICODE:
av = CH_UNICODE[av]
emit(av)
elif op is GROUPREF:
if not flags & SRE_FLAG_IGNORECASE:
emit(op)
elif flags & SRE_FLAG_LOCALE:
emit(GROUPREF_LOC_IGNORE)
elif not fixes: # ascii
emit(GROUPREF_IGNORE)
else:
emit(GROUPREF_UNI_IGNORE)
emit(av-1)
elif op is GROUPREF_EXISTS:
emit(op)
emit(av[0]-1)
skipyes = _len(code); emit(0)
_compile(code, av[1], flags)
if av[2]:
emit(JUMP)
skipno = _len(code); emit(0)
code[skipyes] = _len(code) - skipyes + 1
_compile(code, av[2], flags)
code[skipno] = _len(code) - skipno
else:
code[skipyes] = _len(code) - skipyes + 1
else:
raise error("internal: unsupported operand type %r" % (op,))
def _compile_charset(charset, flags, code):
# compile charset subprogram
emit = code.append
for op, av in charset:
emit(op)
if op is NEGATE:
pass
elif op is LITERAL:
emit(av)
elif op is RANGE or op is RANGE_UNI_IGNORE:
emit(av[0])
emit(av[1])
elif op is CHARSET:
code.extend(av)
elif op is BIGCHARSET:
code.extend(av)
elif op is CATEGORY:
if flags & SRE_FLAG_LOCALE:
emit(CH_LOCALE[av])
elif flags & SRE_FLAG_UNICODE:
emit(CH_UNICODE[av])
else:
emit(av)
else:
raise error("internal: unsupported set operator %r" % (op,))
emit(FAILURE)
def _optimize_charset(charset, iscased=None, fixup=None, fixes=None):
# internal: optimize character set
out = []
tail = []
charmap = bytearray(256)
hascased = False
for op, av in charset:
while True:
try:
if op is LITERAL:
if fixup:
lo = fixup(av)
charmap[lo] = 1
if fixes and lo in fixes:
for k in fixes[lo]:
charmap[k] = 1
if not hascased and iscased(av):
hascased = True
else:
charmap[av] = 1
elif op is RANGE:
r = range(av[0], av[1]+1)
if fixup:
if fixes:
for i in map(fixup, r):
charmap[i] = 1
if i in fixes:
for k in fixes[i]:
charmap[k] = 1
else:
for i in map(fixup, r):
charmap[i] = 1
if not hascased:
hascased = any(map(iscased, r))
else:
for i in r:
charmap[i] = 1
elif op is NEGATE:
out.append((op, av))
else:
tail.append((op, av))
except IndexError:
if len(charmap) == 256:
# character set contains non-UCS1 character codes
charmap += b'\0' * 0xff00
continue
# Character set contains non-BMP character codes.
if fixup:
hascased = True
# There are only two ranges of cased non-BMP characters:
# 10400-1044F (Deseret) and 118A0-118DF (Warang Citi),
# and for both ranges RANGE_UNI_IGNORE works.
if op is RANGE:
op = RANGE_UNI_IGNORE
tail.append((op, av))
break
# compress character map
runs = []
q = 0
while True:
p = charmap.find(1, q)
if p < 0:
break
if len(runs) >= 2:
runs = None
break
q = charmap.find(0, p)
if q < 0:
runs.append((p, len(charmap)))
break
runs.append((p, q))
if runs is not None:
# use literal/range
for p, q in runs:
if q - p == 1:
out.append((LITERAL, p))
else:
out.append((RANGE, (p, q - 1)))
out += tail
# if the case was changed or new representation is more compact
if hascased or len(out) < len(charset):
return out, hascased
# else original character set is good enough
return charset, hascased
# use bitmap
if len(charmap) == 256:
data = _mk_bitmap(charmap)
out.append((CHARSET, data))
out += tail
return out, hascased
# To represent a big charset, first a bitmap of all characters in the
# set is constructed. Then, this bitmap is sliced into chunks of 256
# characters, duplicate chunks are eliminated, and each chunk is
# given a number. In the compiled expression, the charset is
# represented by a 32-bit word sequence, consisting of one word for
# the number of different chunks, a sequence of 256 bytes (64 words)
# of chunk numbers indexed by their original chunk position, and a
# sequence of 256-bit chunks (8 words each).
# Compression is normally good: in a typical charset, large ranges of
# Unicode will be either completely excluded (e.g. if only cyrillic
# letters are to be matched), or completely included (e.g. if large
# subranges of Kanji match). These ranges will be represented by
# chunks of all one-bits or all zero-bits.
# Matching can be also done efficiently: the more significant byte of
# the Unicode character is an index into the chunk number, and the
# less significant byte is a bit index in the chunk (just like the
# CHARSET matching).
charmap = bytes(charmap) # should be hashable
comps = {}
mapping = bytearray(256)
block = 0
data = bytearray()
for i in range(0, 65536, 256):
chunk = charmap[i: i + 256]
if chunk in comps:
mapping[i // 256] = comps[chunk]
else:
mapping[i // 256] = comps[chunk] = block
block += 1
data += chunk
data = _mk_bitmap(data)
data[0:0] = [block] + _bytes_to_codes(mapping)
out.append((BIGCHARSET, data))
out += tail
return out, hascased
_CODEBITS = _sre.CODESIZE * 8
MAXCODE = (1 << _CODEBITS) - 1
_BITS_TRANS = b'0' + b'1' * 255
def _mk_bitmap(bits, _CODEBITS=_CODEBITS, _int=int):
s = bits.translate(_BITS_TRANS)[::-1]
return [_int(s[i - _CODEBITS: i], 2)
for i in range(len(s), 0, -_CODEBITS)]
def _bytes_to_codes(b):
# Convert block indices to word array
a = memoryview(b).cast('I')
assert a.itemsize == _sre.CODESIZE
assert len(a) * a.itemsize == len(b)
return a.tolist()
def _simple(p):
# check if this subpattern is a "simple" operator
if len(p) != 1:
return False
op, av = p[0]
if op is SUBPATTERN:
return av[0] is None and _simple(av[-1])
return op in _UNIT_CODES
def _generate_overlap_table(prefix):
"""
Generate an overlap table for the following prefix.
An overlap table is a table of the same size as the prefix which
informs about the potential self-overlap for each index in the prefix:
- if overlap[i] == 0, prefix[i:] can't overlap prefix[0:...]
- if overlap[i] == k with 0 < k <= i, prefix[i-k+1:i+1] overlaps with
prefix[0:k]
"""
table = [0] * len(prefix)
for i in range(1, len(prefix)):
idx = table[i - 1]
while prefix[i] != prefix[idx]:
if idx == 0:
table[i] = 0
break
idx = table[idx - 1]
else:
table[i] = idx + 1
return table
def _get_iscased(flags):
if not flags & SRE_FLAG_IGNORECASE:
return None
elif flags & SRE_FLAG_UNICODE:
return _sre.unicode_iscased
else:
return _sre.ascii_iscased
def _get_literal_prefix(pattern, flags):
# look for literal prefix
prefix = []
prefixappend = prefix.append
prefix_skip = None
iscased = _get_iscased(flags)
for op, av in pattern.data:
if op is LITERAL:
if iscased and iscased(av):
break
prefixappend(av)
elif op is SUBPATTERN:
group, add_flags, del_flags, p = av
flags1 = _combine_flags(flags, add_flags, del_flags)
if flags1 & SRE_FLAG_IGNORECASE and flags1 & SRE_FLAG_LOCALE:
break
prefix1, prefix_skip1, got_all = _get_literal_prefix(p, flags1)
if prefix_skip is None:
if group is not None:
prefix_skip = len(prefix)
elif prefix_skip1 is not None:
prefix_skip = len(prefix) + prefix_skip1
prefix.extend(prefix1)
if not got_all:
break
else:
break
else:
return prefix, prefix_skip, True
return prefix, prefix_skip, False
def _get_charset_prefix(pattern, flags):
while True:
if not pattern.data:
return None
op, av = pattern.data[0]
if op is not SUBPATTERN:
break
group, add_flags, del_flags, pattern = av
flags = _combine_flags(flags, add_flags, del_flags)
if flags & SRE_FLAG_IGNORECASE and flags & SRE_FLAG_LOCALE:
return None
iscased = _get_iscased(flags)
if op is LITERAL:
if iscased and iscased(av):
return None
return [(op, av)]
elif op is BRANCH:
charset = []
charsetappend = charset.append
for p in av[1]:
if not p:
return None
op, av = p[0]
if op is LITERAL and not (iscased and iscased(av)):
charsetappend((op, av))
else:
return None
return charset
elif op is IN:
charset = av
if iscased:
for op, av in charset:
if op is LITERAL:
if iscased(av):
return None
elif op is RANGE:
if av[1] > 0xffff:
return None
if any(map(iscased, range(av[0], av[1]+1))):
return None
return charset
return None
def _compile_info(code, pattern, flags):
# internal: compile an info block. in the current version,
# this contains min/max pattern width, and an optional literal
# prefix or a character map
lo, hi = pattern.getwidth()
if hi > MAXCODE:
hi = MAXCODE
if lo == 0:
code.extend([INFO, 4, 0, lo, hi])
return
# look for a literal prefix
prefix = []
prefix_skip = 0
charset = [] # not used
if not (flags & SRE_FLAG_IGNORECASE and flags & SRE_FLAG_LOCALE):
# look for literal prefix
prefix, prefix_skip, got_all = _get_literal_prefix(pattern, flags)
# if no prefix, look for charset prefix
if not prefix:
charset = _get_charset_prefix(pattern, flags)
## if prefix:
## print("*** PREFIX", prefix, prefix_skip)
## if charset:
## print("*** CHARSET", charset)
# add an info block
emit = code.append
emit(INFO)
skip = len(code); emit(0)
# literal flag
mask = 0
if prefix:
mask = SRE_INFO_PREFIX
if prefix_skip is None and got_all:
mask = mask | SRE_INFO_LITERAL
elif charset:
mask = mask | SRE_INFO_CHARSET
emit(mask)
# pattern length
if lo < MAXCODE:
emit(lo)
else:
emit(MAXCODE)
prefix = prefix[:MAXCODE]
emit(min(hi, MAXCODE))
# add literal prefix
if prefix:
emit(len(prefix)) # length
if prefix_skip is None:
prefix_skip = len(prefix)
emit(prefix_skip) # skip
code.extend(prefix)
# generate overlap table
code.extend(_generate_overlap_table(prefix))
elif charset:
charset, hascased = _optimize_charset(charset)
assert not hascased
_compile_charset(charset, flags, code)
code[skip] = len(code) - skip
def isstring(obj):
return isinstance(obj, (str, bytes))
def _code(p, flags):
flags = p.state.flags | flags
code = []
# compile info block
_compile_info(code, p, flags)
# compile the pattern
_compile(code, p.data, flags)
code.append(SUCCESS)
return code
def _hex_code(code):
return '[%s]' % ', '.join('%#0*x' % (_sre.CODESIZE*2+2, x) for x in code)
def dis(code):
import sys
labels = set()
level = 0
offset_width = len(str(len(code) - 1))
def dis_(start, end):
def print_(*args, to=None):
if to is not None:
labels.add(to)
args += ('(to %d)' % (to,),)
print('%*d%s ' % (offset_width, start, ':' if start in labels else '.'),
end=' '*(level-1))
print(*args)
def print_2(*args):
print(end=' '*(offset_width + 2*level))
print(*args)
nonlocal level
level += 1
i = start
while i < end:
start = i
op = code[i]
i += 1
op = OPCODES[op]
if op in (SUCCESS, FAILURE, ANY, ANY_ALL,
MAX_UNTIL, MIN_UNTIL, NEGATE):
print_(op)
elif op in (LITERAL, NOT_LITERAL,
LITERAL_IGNORE, NOT_LITERAL_IGNORE,
LITERAL_UNI_IGNORE, NOT_LITERAL_UNI_IGNORE,
LITERAL_LOC_IGNORE, NOT_LITERAL_LOC_IGNORE):
arg = code[i]
i += 1
print_(op, '%#02x (%r)' % (arg, chr(arg)))
elif op is AT:
arg = code[i]
i += 1
arg = str(ATCODES[arg])
assert arg[:3] == 'AT_'
print_(op, arg[3:])
elif op is CATEGORY:
arg = code[i]
i += 1
arg = str(CHCODES[arg])
assert arg[:9] == 'CATEGORY_'
print_(op, arg[9:])
elif op in (IN, IN_IGNORE, IN_UNI_IGNORE, IN_LOC_IGNORE):
skip = code[i]
print_(op, skip, to=i+skip)
dis_(i+1, i+skip)
i += skip
elif op in (RANGE, RANGE_UNI_IGNORE):
lo, hi = code[i: i+2]
i += 2
print_(op, '%#02x %#02x (%r-%r)' % (lo, hi, chr(lo), chr(hi)))
elif op is CHARSET:
print_(op, _hex_code(code[i: i + 256//_CODEBITS]))
i += 256//_CODEBITS
elif op is BIGCHARSET:
arg = code[i]
i += 1
mapping = list(b''.join(x.to_bytes(_sre.CODESIZE, sys.byteorder)
for x in code[i: i + 256//_sre.CODESIZE]))
print_(op, arg, mapping)
i += 256//_sre.CODESIZE
level += 1
for j in range(arg):
print_2(_hex_code(code[i: i + 256//_CODEBITS]))
i += 256//_CODEBITS
level -= 1
elif op in (MARK, GROUPREF, GROUPREF_IGNORE, GROUPREF_UNI_IGNORE,
GROUPREF_LOC_IGNORE):
arg = code[i]
i += 1
print_(op, arg)
elif op is JUMP:
skip = code[i]
print_(op, skip, to=i+skip)
i += 1
elif op is BRANCH:
skip = code[i]
print_(op, skip, to=i+skip)
while skip:
dis_(i+1, i+skip)
i += skip
start = i
skip = code[i]
if skip:
print_('branch', skip, to=i+skip)
else:
print_(FAILURE)
i += 1
elif op in (REPEAT, REPEAT_ONE, MIN_REPEAT_ONE):
skip, min, max = code[i: i+3]
if max == MAXREPEAT:
max = 'MAXREPEAT'
print_(op, skip, min, max, to=i+skip)
dis_(i+3, i+skip)
i += skip
elif op is GROUPREF_EXISTS:
arg, skip = code[i: i+2]
print_(op, arg, skip, to=i+skip)
i += 2
elif op in (ASSERT, ASSERT_NOT):
skip, arg = code[i: i+2]
print_(op, skip, arg, to=i+skip)
dis_(i+2, i+skip)
i += skip
elif op is INFO:
skip, flags, min, max = code[i: i+4]
if max == MAXREPEAT:
max = 'MAXREPEAT'
print_(op, skip, bin(flags), min, max, to=i+skip)
start = i+4
if flags & SRE_INFO_PREFIX:
prefix_len, prefix_skip = code[i+4: i+6]
print_2(' prefix_skip', prefix_skip)
start = i + 6
prefix = code[start: start+prefix_len]
print_2(' prefix',
'[%s]' % ', '.join('%#02x' % x for x in prefix),
'(%r)' % ''.join(map(chr, prefix)))
start += prefix_len
print_2(' overlap', code[start: start+prefix_len])
start += prefix_len
if flags & SRE_INFO_CHARSET:
level += 1
print_2('in')
dis_(start, i+skip)
level -= 1
i += skip
else:
raise ValueError(op)
level -= 1
dis_(0, len(code))
def compile(p, flags=0):
# internal: convert pattern list to internal format
if isstring(p):
pattern = p
p = sre_parse.parse(p, flags)
else:
pattern = None
code = _code(p, flags)
if flags & SRE_FLAG_DEBUG:
print()
dis(code)
# map in either direction
groupindex = p.state.groupdict
indexgroup = [None] * p.state.groups
for k, i in groupindex.items():
indexgroup[i] = k
return _sre.compile(
pattern, flags | p.state.flags, code,
p.state.groups-1,
groupindex, tuple(indexgroup)
)