diff options
Diffstat (limited to 'pcrecpp.cc')
| -rw-r--r-- | pcrecpp.cc | 64 |
1 files changed, 62 insertions, 2 deletions
@@ -80,6 +80,24 @@ static const string empty_string; // If the user doesn't ask for any options, we just use this one static RE_Options default_options; +// Specials for the start of patterns. See comments where start_options is used +// below. (PH June 2018) +static const char *start_options[] = { + "(*UTF8)", + "(*UTF)", + "(*UCP)", + "(*NO_START_OPT)", + "(*NO_AUTO_POSSESS)", + "(*LIMIT_RECURSION=", + "(*LIMIT_MATCH=", + "(*CRLF)", + "(*CR)", + "(*BSR_UNICODE)", + "(*BSR_ANYCRLF)", + "(*ANYCRLF)", + "(*ANY)", + "" }; + void RE::Init(const string& pat, const RE_Options* options) { pattern_ = pat; if (options == NULL) { @@ -135,7 +153,49 @@ pcre* RE::Compile(Anchor anchor) { } else { // Tack a '\z' at the end of RE. Parenthesize it first so that // the '\z' applies to all top-level alternatives in the regexp. - string wrapped = "(?:"; // A non-counting grouping operator + + /* When this code was written (for PCRE 6.0) it was enough just to + parenthesize the entire pattern. Unfortunately, when the feature of + starting patterns with (*UTF8) or (*CR) etc. was added to PCRE patterns, + this code was never updated. This bug was not noticed till 2018, long after + PCRE became obsolescent and its maintainer no longer around. Since PCRE is + frozen, I have added a hack to check for all the existing "start of + pattern" specials - knowing that no new ones will ever be added. I am not a + C++ programmer, so the code style is no doubt crude. It is also + inefficient, but is only run when the pattern starts with "(*". + PH June 2018. */ + + string wrapped = ""; + + if (pattern_.c_str()[0] == '(' && pattern_.c_str()[1] == '*') { + int kk, klen, kmat; + for (;;) { // Loop for any number of leading items + + for (kk = 0; start_options[kk][0] != 0; kk++) { + klen = strlen(start_options[kk]); + kmat = strncmp(pattern_.c_str(), start_options[kk], klen); + if (kmat >= 0) break; + } + if (kmat != 0) break; // Not found + + // If the item ended in "=" we must copy digits up to ")". + + if (start_options[kk][klen-1] == '=') { + while (isdigit(pattern_.c_str()[klen])) klen++; + if (pattern_.c_str()[klen] != ')') break; // Syntax error + klen++; + } + + // Move the item from the pattern to the start of the wrapped string. + + wrapped += pattern_.substr(0, klen); + pattern_.erase(0, klen); + } + } + + // Wrap the rest of the pattern. + + wrapped += "(?:"; // A non-counting grouping operator wrapped += pattern_; wrapped += ")\\z"; re = pcre_compile(wrapped.c_str(), pcre_options, @@ -415,7 +475,7 @@ int RE::GlobalReplace(const StringPiece& rewrite, matchend++; } // We also need to advance more than one char if we're in utf8 mode. -#ifdef SUPPORT_UTF8 +#ifdef SUPPORT_UTF if (options_.utf8()) { while (matchend < static_cast<int>(str->length()) && ((*str)[matchend] & 0xc0) == 0x80) |