blob: a63313e0dcfcd5d1b7bdfe144de3c040f3cd9b15 [file] [log] [blame]
// Copyright 2022 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 <memory>
#include <string>
#include <emscripten/bind.h>
#include "re2/prog.h"
#include "re2/re2.h"
#include "re2/regexp.h"
namespace re2_app {
struct Info {
std::string pattern;
std::string error;
std::string prefix;
bool prefix_foldcase = false;
std::string accel_prefix;
bool accel_prefix_foldcase = false;
int num_captures;
bool is_one_pass;
bool can_bit_state;
std::string bytecode;
std::string bytemap;
Info GetInfo(const std::string& pattern) {
Info info;
info.pattern = pattern;
RE2::Options options;
re2::RegexpStatus status;
re2::Regexp* regexp = re2::Regexp::Parse(
pattern, static_cast<re2::Regexp::ParseFlags>(options.ParseFlags()),
if (regexp == nullptr) {
info.error = "failed to parse pattern: " + status.Text();
return info;
std::string prefix;
bool prefix_foldcase;
re2::Regexp* suffix;
if (regexp->RequiredPrefix(&prefix, &prefix_foldcase, &suffix)) {
info.prefix = prefix;
info.prefix_foldcase = prefix_foldcase;
} else {
suffix = regexp->Incref();
std::unique_ptr<re2::Prog> prog(suffix->CompileToProg(options.max_mem()));
if (prog == nullptr) {
info.error = "failed to compile forward Prog";
return info;
if (regexp->RequiredPrefixForAccel(&prefix, &prefix_foldcase)) {
info.accel_prefix = prefix;
info.accel_prefix_foldcase = prefix_foldcase;
info.num_captures = suffix->NumCaptures();
info.is_one_pass = prog->IsOnePass();
info.can_bit_state = prog->CanBitState();
info.bytecode = prog->Dump();
info.bytemap = prog->DumpByteMap();
return info;
.field("pattern", &Info::pattern)
.field("error", &Info::error)
.field("prefix", &Info::prefix)
.field("prefix_foldcase", &Info::prefix_foldcase)
.field("accel_prefix", &Info::accel_prefix)
.field("accel_prefix_foldcase", &Info::accel_prefix_foldcase)
.field("num_captures", &Info::num_captures)
.field("is_one_pass", &Info::is_one_pass)
.field("can_bit_state", &Info::can_bit_state)
.field("bytecode", &Info::bytecode)
.field("bytemap", &Info::bytemap);
emscripten::function("getInfo", &GetInfo);
} // namespace re2_app