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author | Steve Dower <steve.dower@microsoft.com> | 2017-02-04 15:05:40 -0800 |
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committer | Steve Dower <steve.dower@microsoft.com> | 2017-02-04 15:05:40 -0800 |
commit | b2fa705fd3887c326e811c418469c784353027f4 (patch) | |
tree | b3428f73de91453edbfd4df1a5d4a212d182eb44 /Lib/re.py | |
parent | 134e58fd3aaa2e91390041e143f3f0a21a60142b (diff) | |
parent | b53654b6dbfce8318a7d4d1cdaddca7a7fec194b (diff) | |
download | cpython-b2fa705fd3887c326e811c418469c784353027f4.tar.gz |
Issue #29392: Prevent crash when passing invalid arguments into msvcrt module.
Diffstat (limited to 'Lib/re.py')
-rw-r--r-- | Lib/re.py | 51 |
1 files changed, 26 insertions, 25 deletions
@@ -119,9 +119,10 @@ This module also defines an exception 'error'. """ -import sys +import enum import sre_compile import sre_parse +import functools try: import _locale except ImportError: @@ -138,18 +139,26 @@ __all__ = [ __version__ = "2.2.1" -# flags -A = ASCII = sre_compile.SRE_FLAG_ASCII # assume ascii "locale" -I = IGNORECASE = sre_compile.SRE_FLAG_IGNORECASE # ignore case -L = LOCALE = sre_compile.SRE_FLAG_LOCALE # assume current 8-bit locale -U = UNICODE = sre_compile.SRE_FLAG_UNICODE # assume unicode "locale" -M = MULTILINE = sre_compile.SRE_FLAG_MULTILINE # make anchors look for newline -S = DOTALL = sre_compile.SRE_FLAG_DOTALL # make dot match newline -X = VERBOSE = sre_compile.SRE_FLAG_VERBOSE # ignore whitespace and comments - -# sre extensions (experimental, don't rely on these) -T = TEMPLATE = sre_compile.SRE_FLAG_TEMPLATE # disable backtracking -DEBUG = sre_compile.SRE_FLAG_DEBUG # dump pattern after compilation +class RegexFlag(enum.IntFlag): + ASCII = sre_compile.SRE_FLAG_ASCII # assume ascii "locale" + IGNORECASE = sre_compile.SRE_FLAG_IGNORECASE # ignore case + LOCALE = sre_compile.SRE_FLAG_LOCALE # assume current 8-bit locale + UNICODE = sre_compile.SRE_FLAG_UNICODE # assume unicode "locale" + MULTILINE = sre_compile.SRE_FLAG_MULTILINE # make anchors look for newline + DOTALL = sre_compile.SRE_FLAG_DOTALL # make dot match newline + VERBOSE = sre_compile.SRE_FLAG_VERBOSE # ignore whitespace and comments + A = ASCII + I = IGNORECASE + L = LOCALE + U = UNICODE + M = MULTILINE + S = DOTALL + X = VERBOSE + # sre extensions (experimental, don't rely on these) + TEMPLATE = sre_compile.SRE_FLAG_TEMPLATE # disable backtracking + T = TEMPLATE + DEBUG = sre_compile.SRE_FLAG_DEBUG # dump pattern after compilation +globals().update(RegexFlag.__members__) # sre exception error = sre_compile.error @@ -226,7 +235,7 @@ def compile(pattern, flags=0): def purge(): "Clear the regular expression caches" _cache.clear() - _cache_repl.clear() + _compile_repl.cache_clear() def template(pattern, flags=0): "Compile a template pattern, returning a pattern object" @@ -270,7 +279,6 @@ def escape(pattern): # internals _cache = {} -_cache_repl = {} _pattern_type = type(sre_compile.compile("", 0)) @@ -303,17 +311,10 @@ def _compile(pattern, flags): _cache[type(pattern), pattern, flags] = p, loc return p +@functools.lru_cache(_MAXCACHE) def _compile_repl(repl, pattern): # internal: compile replacement pattern - try: - return _cache_repl[repl, pattern] - except KeyError: - pass - p = sre_parse.parse_template(repl, pattern) - if len(_cache_repl) >= _MAXCACHE: - _cache_repl.clear() - _cache_repl[repl, pattern] = p - return p + return sre_parse.parse_template(repl, pattern) def _expand(pattern, match, template): # internal: match.expand implementation hook @@ -353,7 +354,7 @@ class Scanner: for phrase, action in lexicon: gid = s.opengroup() p.append(sre_parse.SubPattern(s, [ - (SUBPATTERN, (gid, sre_parse.parse(phrase, flags))), + (SUBPATTERN, (gid, 0, 0, sre_parse.parse(phrase, flags))), ])) s.closegroup(gid, p[-1]) p = sre_parse.SubPattern(s, [(BRANCH, (None, p))]) |