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-rw-r--r--lib/python2.7/sre_compile.py525
1 files changed, 525 insertions, 0 deletions
diff --git a/lib/python2.7/sre_compile.py b/lib/python2.7/sre_compile.py
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+++ b/lib/python2.7/sre_compile.py
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+#
+# 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, sys
+import sre_parse
+from sre_constants import *
+from _sre import MAXREPEAT
+
+assert _sre.MAGIC == MAGIC, "SRE module mismatch"
+
+if _sre.CODESIZE == 2:
+ MAXCODE = 65535
+else:
+ MAXCODE = 0xFFFFFFFFL
+
+def _identityfunction(x):
+ return x
+
+_LITERAL_CODES = set([LITERAL, NOT_LITERAL])
+_REPEATING_CODES = set([REPEAT, MIN_REPEAT, MAX_REPEAT])
+_SUCCESS_CODES = set([SUCCESS, FAILURE])
+_ASSERT_CODES = set([ASSERT, ASSERT_NOT])
+
+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
+ for op, av in pattern:
+ if op in LITERAL_CODES:
+ if flags & SRE_FLAG_IGNORECASE:
+ emit(OPCODES[OP_IGNORE[op]])
+ emit(_sre.getlower(av, flags))
+ else:
+ emit(OPCODES[op])
+ emit(av)
+ elif op is IN:
+ if flags & SRE_FLAG_IGNORECASE:
+ emit(OPCODES[OP_IGNORE[op]])
+ def fixup(literal, flags=flags):
+ return _sre.getlower(literal, flags)
+ else:
+ emit(OPCODES[op])
+ fixup = _identityfunction
+ skip = _len(code); emit(0)
+ _compile_charset(av, flags, code, fixup)
+ code[skip] = _len(code) - skip
+ elif op is ANY:
+ if flags & SRE_FLAG_DOTALL:
+ emit(OPCODES[ANY_ALL])
+ else:
+ emit(OPCODES[ANY])
+ elif op in REPEATING_CODES:
+ if flags & SRE_FLAG_TEMPLATE:
+ raise error, "internal: unsupported template operator"
+ emit(OPCODES[REPEAT])
+ skip = _len(code); emit(0)
+ emit(av[0])
+ emit(av[1])
+ _compile(code, av[2], flags)
+ emit(OPCODES[SUCCESS])
+ code[skip] = _len(code) - skip
+ elif _simple(av) and op is not REPEAT:
+ if op is MAX_REPEAT:
+ emit(OPCODES[REPEAT_ONE])
+ else:
+ emit(OPCODES[MIN_REPEAT_ONE])
+ skip = _len(code); emit(0)
+ emit(av[0])
+ emit(av[1])
+ _compile(code, av[2], flags)
+ emit(OPCODES[SUCCESS])
+ code[skip] = _len(code) - skip
+ else:
+ emit(OPCODES[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(OPCODES[MAX_UNTIL])
+ else:
+ emit(OPCODES[MIN_UNTIL])
+ elif op is SUBPATTERN:
+ if av[0]:
+ emit(OPCODES[MARK])
+ emit((av[0]-1)*2)
+ # _compile_info(code, av[1], flags)
+ _compile(code, av[1], flags)
+ if av[0]:
+ emit(OPCODES[MARK])
+ emit((av[0]-1)*2+1)
+ elif op in SUCCESS_CODES:
+ emit(OPCODES[op])
+ elif op in ASSERT_CODES:
+ emit(OPCODES[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(OPCODES[SUCCESS])
+ code[skip] = _len(code) - skip
+ elif op is CALL:
+ emit(OPCODES[op])
+ skip = _len(code); emit(0)
+ _compile(code, av, flags)
+ emit(OPCODES[SUCCESS])
+ code[skip] = _len(code) - skip
+ elif op is AT:
+ emit(OPCODES[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(ATCODES[av])
+ elif op is BRANCH:
+ emit(OPCODES[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(OPCODES[JUMP])
+ tailappend(_len(code)); emit(0)
+ code[skip] = _len(code) - skip
+ emit(0) # end of branch
+ for tail in tail:
+ code[tail] = _len(code) - tail
+ elif op is CATEGORY:
+ emit(OPCODES[op])
+ if flags & SRE_FLAG_LOCALE:
+ av = CH_LOCALE[av]
+ elif flags & SRE_FLAG_UNICODE:
+ av = CH_UNICODE[av]
+ emit(CHCODES[av])
+ elif op is GROUPREF:
+ if flags & SRE_FLAG_IGNORECASE:
+ emit(OPCODES[OP_IGNORE[op]])
+ else:
+ emit(OPCODES[op])
+ emit(av-1)
+ elif op is GROUPREF_EXISTS:
+ emit(OPCODES[op])
+ emit(av[0]-1)
+ skipyes = _len(code); emit(0)
+ _compile(code, av[1], flags)
+ if av[2]:
+ emit(OPCODES[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 ValueError, ("unsupported operand type", op)
+
+def _compile_charset(charset, flags, code, fixup=None):
+ # compile charset subprogram
+ emit = code.append
+ if fixup is None:
+ fixup = _identityfunction
+ for op, av in _optimize_charset(charset, fixup):
+ emit(OPCODES[op])
+ if op is NEGATE:
+ pass
+ elif op is LITERAL:
+ emit(fixup(av))
+ elif op is RANGE:
+ emit(fixup(av[0]))
+ emit(fixup(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(CHCODES[CH_LOCALE[av]])
+ elif flags & SRE_FLAG_UNICODE:
+ emit(CHCODES[CH_UNICODE[av]])
+ else:
+ emit(CHCODES[av])
+ else:
+ raise error, "internal: unsupported set operator"
+ emit(OPCODES[FAILURE])
+
+def _optimize_charset(charset, fixup):
+ # internal: optimize character set
+ out = []
+ outappend = out.append
+ charmap = [0]*256
+ try:
+ for op, av in charset:
+ if op is NEGATE:
+ outappend((op, av))
+ elif op is LITERAL:
+ charmap[fixup(av)] = 1
+ elif op is RANGE:
+ for i in range(fixup(av[0]), fixup(av[1])+1):
+ charmap[i] = 1
+ elif op is CATEGORY:
+ # XXX: could append to charmap tail
+ return charset # cannot compress
+ except IndexError:
+ # character set contains unicode characters
+ return _optimize_unicode(charset, fixup)
+ # compress character map
+ i = p = n = 0
+ runs = []
+ runsappend = runs.append
+ for c in charmap:
+ if c:
+ if n == 0:
+ p = i
+ n = n + 1
+ elif n:
+ runsappend((p, n))
+ n = 0
+ i = i + 1
+ if n:
+ runsappend((p, n))
+ if len(runs) <= 2:
+ # use literal/range
+ for p, n in runs:
+ if n == 1:
+ outappend((LITERAL, p))
+ else:
+ outappend((RANGE, (p, p+n-1)))
+ if len(out) < len(charset):
+ return out
+ else:
+ # use bitmap
+ data = _mk_bitmap(charmap)
+ outappend((CHARSET, data))
+ return out
+ return charset
+
+def _mk_bitmap(bits):
+ data = []
+ dataappend = data.append
+ if _sre.CODESIZE == 2:
+ start = (1, 0)
+ else:
+ start = (1L, 0L)
+ m, v = start
+ for c in bits:
+ if c:
+ v = v + m
+ m = m + m
+ if m > MAXCODE:
+ dataappend(v)
+ m, v = start
+ return data
+
+# 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 16-bit word sequence, consisting of one word for
+# the number of different chunks, a sequence of 256 bytes (128 words)
+# of chunk numbers indexed by their original chunk position, and a
+# sequence of chunks (16 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).
+
+# In UCS-4 mode, the BIGCHARSET opcode still supports only subsets
+# of the basic multilingual plane; an efficient representation
+# for all of UTF-16 has not yet been developed. This means,
+# in particular, that negated charsets cannot be represented as
+# bigcharsets.
+
+def _optimize_unicode(charset, fixup):
+ try:
+ import array
+ except ImportError:
+ return charset
+ charmap = [0]*65536
+ negate = 0
+ try:
+ for op, av in charset:
+ if op is NEGATE:
+ negate = 1
+ elif op is LITERAL:
+ charmap[fixup(av)] = 1
+ elif op is RANGE:
+ for i in xrange(fixup(av[0]), fixup(av[1])+1):
+ charmap[i] = 1
+ elif op is CATEGORY:
+ # XXX: could expand category
+ return charset # cannot compress
+ except IndexError:
+ # non-BMP characters
+ return charset
+ if negate:
+ if sys.maxunicode != 65535:
+ # XXX: negation does not work with big charsets
+ return charset
+ for i in xrange(65536):
+ charmap[i] = not charmap[i]
+ comps = {}
+ mapping = [0]*256
+ block = 0
+ data = []
+ for i in xrange(256):
+ chunk = tuple(charmap[i*256:(i+1)*256])
+ new = comps.setdefault(chunk, block)
+ mapping[i] = new
+ if new == block:
+ block = block + 1
+ data = data + _mk_bitmap(chunk)
+ header = [block]
+ if _sre.CODESIZE == 2:
+ code = 'H'
+ else:
+ code = 'I'
+ # Convert block indices to byte array of 256 bytes
+ mapping = array.array('b', mapping).tostring()
+ # Convert byte array to word array
+ mapping = array.array(code, mapping)
+ assert mapping.itemsize == _sre.CODESIZE
+ header = header + mapping.tolist()
+ data[0:0] = header
+ return [(BIGCHARSET, data)]
+
+def _simple(av):
+ # check if av is a "simple" operator
+ lo, hi = av[2].getwidth()
+ if lo == 0 and hi == MAXREPEAT:
+ raise error, "nothing to repeat"
+ return lo == hi == 1 and av[2][0][0] != SUBPATTERN
+
+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 lo == 0:
+ return # not worth it
+ # look for a literal prefix
+ prefix = []
+ prefixappend = prefix.append
+ prefix_skip = 0
+ charset = [] # not used
+ charsetappend = charset.append
+ if not (flags & SRE_FLAG_IGNORECASE):
+ # look for literal prefix
+ for op, av in pattern.data:
+ if op is LITERAL:
+ if len(prefix) == prefix_skip:
+ prefix_skip = prefix_skip + 1
+ prefixappend(av)
+ elif op is SUBPATTERN and len(av[1]) == 1:
+ op, av = av[1][0]
+ if op is LITERAL:
+ prefixappend(av)
+ else:
+ break
+ else:
+ break
+ # if no prefix, look for charset prefix
+ if not prefix and pattern.data:
+ op, av = pattern.data[0]
+ if op is SUBPATTERN and av[1]:
+ op, av = av[1][0]
+ if op is LITERAL:
+ charsetappend((op, av))
+ elif op is BRANCH:
+ c = []
+ cappend = c.append
+ for p in av[1]:
+ if not p:
+ break
+ op, av = p[0]
+ if op is LITERAL:
+ cappend((op, av))
+ else:
+ break
+ else:
+ charset = c
+ elif op is BRANCH:
+ c = []
+ cappend = c.append
+ for p in av[1]:
+ if not p:
+ break
+ op, av = p[0]
+ if op is LITERAL:
+ cappend((op, av))
+ else:
+ break
+ else:
+ charset = c
+ elif op is IN:
+ charset = av
+## if prefix:
+## print "*** PREFIX", prefix, prefix_skip
+## if charset:
+## print "*** CHARSET", charset
+ # add an info block
+ emit = code.append
+ emit(OPCODES[INFO])
+ skip = len(code); emit(0)
+ # literal flag
+ mask = 0
+ if prefix:
+ mask = SRE_INFO_PREFIX
+ if len(prefix) == prefix_skip == len(pattern.data):
+ 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]
+ if hi < MAXCODE:
+ emit(hi)
+ else:
+ emit(0)
+ # add literal prefix
+ if prefix:
+ emit(len(prefix)) # length
+ emit(prefix_skip) # skip
+ code.extend(prefix)
+ # generate overlap table
+ table = [-1] + ([0]*len(prefix))
+ for i in xrange(len(prefix)):
+ table[i+1] = table[i]+1
+ while table[i+1] > 0 and prefix[i] != prefix[table[i+1]-1]:
+ table[i+1] = table[table[i+1]-1]+1
+ code.extend(table[1:]) # don't store first entry
+ elif charset:
+ _compile_charset(charset, flags, code)
+ code[skip] = len(code) - skip
+
+try:
+ unicode
+except NameError:
+ STRING_TYPES = (type(""),)
+else:
+ STRING_TYPES = (type(""), type(unicode("")))
+
+def isstring(obj):
+ for tp in STRING_TYPES:
+ if isinstance(obj, tp):
+ return 1
+ return 0
+
+def _code(p, flags):
+
+ flags = p.pattern.flags | flags
+ code = []
+
+ # compile info block
+ _compile_info(code, p, flags)
+
+ # compile the pattern
+ _compile(code, p.data, flags)
+
+ code.append(OPCODES[SUCCESS])
+
+ return 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)
+
+ # print code
+
+ # XXX: <fl> get rid of this limitation!
+ if p.pattern.groups > 100:
+ raise AssertionError(
+ "sorry, but this version only supports 100 named groups"
+ )
+
+ # map in either direction
+ groupindex = p.pattern.groupdict
+ indexgroup = [None] * p.pattern.groups
+ for k, i in groupindex.items():
+ indexgroup[i] = k
+
+ return _sre.compile(
+ pattern, flags | p.pattern.flags, code,
+ p.pattern.groups-1,
+ groupindex, indexgroup
+ )
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-01 07:58:52 +0000