urbit/outside/re2/re2/set.cc
Steve Dee 27dd121d14 Add 'outside/re2/' from commit '539b44fc4c5a49c3453b80e3af85d297f4cab4bf'
git-subtree-dir: outside/re2
git-subtree-mainline: f94738bfd171ae447133e0964843addbb497894f
git-subtree-split: 539b44fc4c5a49c3453b80e3af85d297f4cab4bf
2014-04-10 11:36:47 -07:00

114 lines
2.8 KiB
C++

// Copyright 2010 The RE2 Authors. All Rights Reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "re2/set.h"
#include "util/util.h"
#include "re2/stringpiece.h"
#include "re2/prog.h"
#include "re2/re2.h"
#include "re2/regexp.h"
using namespace re2;
RE2::Set::Set(const RE2::Options& options, RE2::Anchor anchor) {
options_.Copy(options);
anchor_ = anchor;
prog_ = NULL;
compiled_ = false;
}
RE2::Set::~Set() {
for (int i = 0; i < re_.size(); i++)
re_[i]->Decref();
delete prog_;
}
int RE2::Set::Add(const StringPiece& pattern, string* error) {
if (compiled_) {
LOG(DFATAL) << "RE2::Set::Add after Compile";
return -1;
}
Regexp::ParseFlags pf = static_cast<Regexp::ParseFlags>(
options_.ParseFlags());
RegexpStatus status;
re2::Regexp* re = Regexp::Parse(pattern, pf, &status);
if (re == NULL) {
if (error != NULL)
*error = status.Text();
if (options_.log_errors())
LOG(ERROR) << "Error parsing '" << pattern << "': " << status.Text();
return -1;
}
// Concatenate with match index and push on vector.
int n = re_.size();
re2::Regexp* m = re2::Regexp::HaveMatch(n, pf);
if (re->op() == kRegexpConcat) {
int nsub = re->nsub();
re2::Regexp** sub = new re2::Regexp*[nsub + 1];
for (int i = 0; i < nsub; i++)
sub[i] = re->sub()[i]->Incref();
sub[nsub] = m;
re->Decref();
re = re2::Regexp::Concat(sub, nsub + 1, pf);
delete[] sub;
} else {
re2::Regexp* sub[2];
sub[0] = re;
sub[1] = m;
re = re2::Regexp::Concat(sub, 2, pf);
}
re_.push_back(re);
return n;
}
bool RE2::Set::Compile() {
if (compiled_) {
LOG(DFATAL) << "RE2::Set::Compile multiple times";
return false;
}
compiled_ = true;
Regexp::ParseFlags pf = static_cast<Regexp::ParseFlags>(
options_.ParseFlags());
re2::Regexp* re = re2::Regexp::Alternate(const_cast<re2::Regexp**>(&re_[0]),
re_.size(), pf);
re_.clear();
re2::Regexp* sre = re->Simplify();
re->Decref();
re = sre;
if (re == NULL) {
if (options_.log_errors())
LOG(ERROR) << "Error simplifying during Compile.";
return false;
}
prog_ = Prog::CompileSet(options_, anchor_, re);
return prog_ != NULL;
}
bool RE2::Set::Match(const StringPiece& text, vector<int>* v) const {
if (!compiled_) {
LOG(DFATAL) << "RE2::Set::Match without Compile";
return false;
}
v->clear();
bool failed;
bool ret = prog_->SearchDFA(text, text, Prog::kAnchored,
Prog::kManyMatch, NULL, &failed, v);
if (failed)
LOG(DFATAL) << "RE2::Set::Match: DFA ran out of cache space";
if (ret == false)
return false;
if (v->size() == 0) {
LOG(DFATAL) << "RE2::Set::Match: match but unknown regexp set";
return false;
}
return true;
}