1 //===-- Regex.cpp - Regular Expression matcher implementation -------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements a POSIX regular expression matcher.
12 //===----------------------------------------------------------------------===//
13 #include "llvm/Support/Regex.h"
14 #include "llvm/Support/ErrorHandling.h"
15 #include "llvm/Support/raw_ostream.h"
16 #include "regex_impl.h"
20 Regex::Regex(const StringRef ®ex, unsigned Flags)
23 preg = new struct llvm_regex;
24 preg->re_endp = regex.end();
25 if (Flags & IgnoreCase)
35 error = llvm_regcomp(preg, regex.data(), flags|REG_EXTENDED|REG_PEND);
38 bool Regex::isValid(std::string &Error)
43 size_t len = llvm_regerror(error, preg, NULL, 0);
44 char *errbuff = new char[len];
45 llvm_regerror(error, preg, errbuff, len);
46 Error.assign(errbuff);
56 bool Regex::match(const StringRef &String, SmallVectorImpl<StringRef> *Matches)
58 unsigned nmatch = Matches ? preg->re_nsub+1 : 0;
61 assert(sub && "Substring matching requested but pattern compiled without");
65 // pmatch needs to have at least one element.
66 SmallVector<llvm_regmatch_t, 2> pm;
67 pm.resize(nmatch > 0 ? nmatch : 1);
69 pm[0].rm_eo = String.size();
71 int rc = llvm_regexec(preg, String.data(), nmatch, pm.data(), REG_STARTEND);
73 if (rc == REG_NOMATCH)
76 // regexec can fail due to invalid pattern or running out of memory.
83 if (Matches) { // match position requested
84 for (unsigned i=0;i<nmatch; i++) {
85 if (pm[i].rm_so == -1) {
86 // this group didn't match
87 Matches->push_back(StringRef());
90 assert(pm[i].rm_eo > pm[i].rm_so);
91 Matches->push_back(StringRef(String.data()+pm[i].rm_so,
92 pm[i].rm_eo-pm[i].rm_so));