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-rw-r--r--Lib/dos-8x3/sre_pars.py263
1 files changed, 154 insertions, 109 deletions
diff --git a/Lib/dos-8x3/sre_pars.py b/Lib/dos-8x3/sre_pars.py
index 53616f618fc..a50191ec9b0 100644
--- a/Lib/dos-8x3/sre_pars.py
+++ b/Lib/dos-8x3/sre_pars.py
@@ -5,33 +5,24 @@
#
# Copyright (c) 1998-2000 by Secret Labs AB. All rights reserved.
#
-# Portions of this engine have been developed in cooperation with
-# CNRI. Hewlett-Packard provided funding for 1.6 integration and
-# other compatibility work.
+# See the sre.py file for information on usage and redistribution.
#
import string, sys
-import _sre
-
from sre_constants import *
-# FIXME: should be 65535, but the arraymodule is still broken
-MAXREPEAT = 32767
-
-# FIXME: might change in 2.0 final. but for now, this seems
-# to be the best way to be compatible with 1.5.2
-CHARMASK = 0xff
+MAXREPEAT = 65535
SPECIAL_CHARS = ".\\[{()*+?^$|"
REPEAT_CHARS = "*+?{"
-DIGITS = tuple(string.digits)
+DIGITS = tuple("012345689")
OCTDIGITS = tuple("01234567")
HEXDIGITS = tuple("0123456789abcdefABCDEF")
-WHITESPACE = tuple(string.whitespace)
+WHITESPACE = tuple(" \t\n\r\v\f")
ESCAPES = {
r"\a": (LITERAL, 7),
@@ -69,7 +60,8 @@ FLAGS = {
"u": SRE_FLAG_UNICODE,
}
-class State:
+class Pattern:
+ # master pattern object. keeps track of global attributes
def __init__(self):
self.flags = 0
self.groups = 1
@@ -89,6 +81,33 @@ class SubPattern:
data = []
self.data = data
self.width = None
+ def dump(self, level=0):
+ nl = 1
+ for op, av in self.data:
+ print level*" " + op,; nl = 0
+ if op == "in":
+ # member sublanguage
+ print; nl = 1
+ for op, a in av:
+ print (level+1)*" " + op, a
+ elif op == "branch":
+ print; nl = 1
+ i = 0
+ for a in av[1]:
+ if i > 0:
+ print level*" " + "or"
+ a.dump(level+1); nl = 1
+ i = i + 1
+ elif type(av) in (type(()), type([])):
+ for a in av:
+ if isinstance(a, SubPattern):
+ if not nl: print
+ a.dump(level+1); nl = 1
+ else:
+ print a, ; nl = 0
+ else:
+ print av, ; nl = 0
+ if not nl: print
def __repr__(self):
return repr(self.data)
def __len__(self):
@@ -112,12 +131,12 @@ class SubPattern:
lo = hi = 0L
for op, av in self.data:
if op is BRANCH:
- l = sys.maxint
- h = 0
+ i = sys.maxint
+ j = 0
for av in av[1]:
- i, j = av.getwidth()
- l = min(l, i)
- h = min(h, j)
+ l, h = av.getwidth()
+ i = min(i, l)
+ j = max(j, h)
lo = lo + i
hi = hi + j
elif op is CALL:
@@ -142,12 +161,13 @@ class SubPattern:
class Tokenizer:
def __init__(self, string):
- self.index = 0
self.string = string
- self.next = self.__next()
+ self.index = 0
+ self.__next()
def __next(self):
if self.index >= len(self.string):
- return None
+ self.next = None
+ return
char = self.string[self.index]
if char[0] == "\\":
try:
@@ -156,21 +176,21 @@ class Tokenizer:
raise error, "bogus escape"
char = char + c
self.index = self.index + len(char)
- return char
- def match(self, char):
+ self.next = char
+ def match(self, char, skip=1):
if char == self.next:
- self.next = self.__next()
- return 1
- return 0
- def match_set(self, set):
- if self.next and self.next in set:
- self.next = self.__next()
+ if skip:
+ self.__next()
return 1
return 0
def get(self):
this = self.next
- self.next = self.__next()
+ self.__next()
return this
+ def tell(self):
+ return self.index, self.next
+ def seek(self, index):
+ self.index, self.next = index
def isident(char):
return "a" <= char <= "z" or "A" <= char <= "Z" or char == "_"
@@ -207,15 +227,19 @@ def _class_escape(source, escape):
return code
try:
if escape[1:2] == "x":
- while source.next in HEXDIGITS:
+ # hexadecimal escape (exactly two digits)
+ while source.next in HEXDIGITS and len(escape) < 4:
escape = escape + source.get()
escape = escape[2:]
- return LITERAL, int(escape[-4:], 16) & CHARMASK
+ if len(escape) != 2:
+ raise error, "bogus escape: %s" % repr("\\" + escape)
+ return LITERAL, int(escape, 16) & 0xff
elif str(escape[1:2]) in OCTDIGITS:
- while source.next in OCTDIGITS:
+ # octal escape (up to three digits)
+ while source.next in OCTDIGITS and len(escape) < 5:
escape = escape + source.get()
escape = escape[1:]
- return LITERAL, int(escape[-6:], 8) & CHARMASK
+ return LITERAL, int(escape, 8) & 0xff
if len(escape) == 2:
return LITERAL, ord(escape[1])
except ValueError:
@@ -232,34 +256,57 @@ def _escape(source, escape, state):
return code
try:
if escape[1:2] == "x":
- while source.next in HEXDIGITS:
+ # hexadecimal escape
+ while source.next in HEXDIGITS and len(escape) < 4:
escape = escape + source.get()
escape = escape[2:]
- return LITERAL, int(escape[-4:], 16) & CHARMASK
+ if len(escape) != 2:
+ raise error, "bogus escape: %s" % repr("\\" + escape)
+ return LITERAL, int(escape, 16) & 0xff
+ elif escape[1:2] == "0":
+ # octal escape
+ while source.next in OCTDIGITS and len(escape) < 5:
+ escape = escape + source.get()
+ return LITERAL, int(escape[1:], 8) & 0xff
elif escape[1:2] in DIGITS:
- while 1:
- group = _group(escape, state.groups)
- if group:
- if (not source.next or
- not _group(escape + source.next, state.groups)):
- return GROUP, group
- escape = escape + source.get()
- elif source.next in OCTDIGITS:
+ # octal escape *or* decimal group reference (sigh)
+ here = source.tell()
+ if source.next in DIGITS:
+ escape = escape + source.get()
+ if escape[2] in OCTDIGITS and source.next in OCTDIGITS:
+ # got three octal digits; this is an octal escape
escape = escape + source.get()
- else:
- break
- escape = escape[1:]
- return LITERAL, int(escape[-6:], 8) & CHARMASK
+ return LITERAL, int(escape[1:], 8) & 0xff
+ # got at least one decimal digit; this is a group reference
+ group = _group(escape, state.groups)
+ if group:
+ return GROUPREF, group
+ raise error, "bogus escape: %s" % repr(escape)
if len(escape) == 2:
return LITERAL, ord(escape[1])
except ValueError:
pass
raise error, "bogus escape: %s" % repr(escape)
-def _branch(pattern, items):
- # form a branch operator from a set of items
+def _parse_sub(source, state, nested=1):
+ # parse an alternation: a|b|c
+
+ items = []
+ while 1:
+ items.append(_parse(source, state))
+ if source.match("|"):
+ continue
+ if not nested:
+ break
+ if not source.next or source.match(")", 0):
+ break
+ else:
+ raise error, "pattern not properly closed"
- subpattern = SubPattern(pattern)
+ if len(items) == 1:
+ return items[0]
+
+ subpattern = SubPattern(state)
# check if all items share a common prefix
while 1:
@@ -286,7 +333,7 @@ def _branch(pattern, items):
break
else:
# we can store this as a character set instead of a
- # branch (FIXME: use a range if possible)
+ # branch (the compiler may optimize this even more)
set = []
for item in items:
set.append(item[0])
@@ -297,8 +344,7 @@ def _branch(pattern, items):
return subpattern
def _parse(source, state):
-
- # parse regular expression pattern into an operator list.
+ # parse a simple pattern
subpattern = SubPattern(state)
@@ -357,7 +403,11 @@ def _parse(source, state):
code2 = LITERAL, ord(this)
if code1[0] != LITERAL or code2[0] != LITERAL:
raise error, "illegal range"
- set.append((RANGE, (code1[1], code2[1])))
+ lo = code1[1]
+ hi = code2[1]
+ if hi < lo:
+ raise error, "illegal range"
+ set.append((RANGE, (lo, hi)))
else:
if code1[0] is IN:
code1 = code1[1][0]
@@ -381,6 +431,7 @@ def _parse(source, state):
elif this == "+":
min, max = 1, MAXREPEAT
elif this == "{":
+ here = source.tell()
min, max = 0, MAXREPEAT
lo = hi = ""
while source.next in DIGITS:
@@ -391,7 +442,9 @@ def _parse(source, state):
else:
hi = lo
if not source.match("}"):
- raise error, "bogus range"
+ subpattern.append((LITERAL, ord(this)))
+ source.seek(here)
+ continue
if lo:
min = int(lo)
if hi:
@@ -448,7 +501,8 @@ def _parse(source, state):
gid = state.groupdict.get(name)
if gid is None:
raise error, "unknown group name"
- subpattern.append((GROUP, gid))
+ subpattern.append((GROUPREF, gid))
+ continue
else:
char = source.get()
if char is None:
@@ -463,49 +517,41 @@ def _parse(source, state):
if source.next is None or source.next == ")":
break
source.get()
- elif source.next in ("=", "!"):
+ if not source.match(")"):
+ raise error, "unbalanced parenthesis"
+ continue
+ elif source.next in ("=", "!", "<"):
# lookahead assertions
char = source.get()
- b = []
- while 1:
- p = _parse(source, state)
- if source.next == ")":
- if b:
- b.append(p)
- p = _branch(state, b)
- if char == "=":
- subpattern.append((ASSERT, p))
- else:
- subpattern.append((ASSERT_NOT, p))
- break
- elif source.match("|"):
- b.append(p)
- else:
- raise error, "pattern not properly closed"
+ dir = 1
+ if char == "<":
+ if source.next not in ("=", "!"):
+ raise error, "syntax error"
+ dir = -1 # lookbehind
+ char = source.get()
+ p = _parse_sub(source, state)
+ if not source.match(")"):
+ raise error, "unbalanced parenthesis"
+ if char == "=":
+ subpattern.append((ASSERT, (dir, p)))
+ else:
+ subpattern.append((ASSERT_NOT, (dir, p)))
+ continue
else:
# flags
while FLAGS.has_key(source.next):
state.flags = state.flags | FLAGS[source.get()]
if group:
# parse group contents
- b = []
if group == 2:
# anonymous group
group = None
else:
group = state.getgroup(name)
- while 1:
- p = _parse(source, state)
- if source.match(")"):
- if b:
- b.append(p)
- p = _branch(state, b)
- subpattern.append((SUBPATTERN, (group, p)))
- break
- elif source.match("|"):
- b.append(p)
- else:
- raise error, "group not properly closed"
+ p = _parse_sub(source, state)
+ if not source.match(")"):
+ raise error, "unbalanced parenthesis"
+ subpattern.append((SUBPATTERN, (group, p)))
else:
while 1:
char = source.get()
@@ -528,26 +574,25 @@ def _parse(source, state):
return subpattern
-def parse(pattern, flags=0):
+def parse(str, flags=0, pattern=None):
# parse 're' pattern into list of (opcode, argument) tuples
- source = Tokenizer(pattern)
- state = State()
- state.flags = flags
- b = []
- while 1:
- p = _parse(source, state)
- tail = source.get()
- if tail == "|":
- b.append(p)
- elif tail == ")":
- raise error, "unbalanced parenthesis"
- elif tail is None:
- if b:
- b.append(p)
- p = _branch(state, b)
- break
- else:
- raise error, "bogus characters at end of regular expression"
+
+ source = Tokenizer(str)
+
+ if pattern is None:
+ pattern = Pattern()
+ pattern.flags = flags
+
+ p = _parse_sub(source, pattern, 0)
+
+ tail = source.get()
+ if tail == ")":
+ raise error, "unbalanced parenthesis"
+ elif tail:
+ raise error, "bogus characters at end of regular expression"
+
+ # p.dump()
+
return p
def parse_template(source, pattern):
@@ -599,7 +644,7 @@ def parse_template(source, pattern):
break
if not code:
this = this[1:]
- code = LITERAL, int(this[-6:], 8) & CHARMASK
+ code = LITERAL, int(this[-6:], 8) & 0xff
a(code)
else:
try:
@@ -629,4 +674,4 @@ def expand_template(template, match):
if s is None:
raise error, "empty group"
a(s)
- return sep.join(p)
+ return string.join(p, sep)
generated by cgit v1.2.3 (git 2.39.1) at 2025-06-05 02:44:49 +0000