/*
* Copyright (c) 2015, Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Intel Corporation nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/** \file
* \brief Alternations (foo|bar|baz).
*/
#include "ComponentAlternation.h"
#include "buildstate.h"
#include "position.h"
#include "position_info.h"
#include "nfagraph/ng_builder.h"
#include "ue2common.h"
#include <algorithm>
using namespace std;
namespace ue2 {
ComponentAlternation::ComponentAlternation() {
// empty
}
ComponentAlternation::~ComponentAlternation() {
// empty
}
ComponentAlternation::ComponentAlternation(const ComponentAlternation &other)
: Component(other) {
for (const auto &c : other.children) {
assert(c);
children.push_back(unique_ptr<Component>(c->clone()));
}
}
ComponentAlternation * ComponentAlternation::clone() const {
return new ComponentAlternation(*this);
}
Component *ComponentAlternation::accept(ComponentVisitor &v) {
Component *c = v.visit(this);
if (c != this) {
v.post(this);
return c;
}
for (auto i = children.begin(), e = children.end(); i != e; ++i) {
Component *child = i->get();
c = (*i)->accept(v);
if (c != child) {
// Child has been replaced (new Component pointer) or we've been
// instructed to delete it (null).
i->reset(c);
}
}
// Remove deleted children.
children.erase(remove(children.begin(), children.end(), nullptr),
children.end());
v.post(this);
return this;
}
void ComponentAlternation::accept(ConstComponentVisitor &v) const {
v.pre(*this);
for (auto i = children.begin(), e = children.end(); i != e; ++i) {
(*i)->accept(v);
if (i + 1 != e) {
v.during(*this);
}
}
v.post(*this);
}
void ComponentAlternation::append(unique_ptr<Component> component) {
children.push_back(move(component));
}
vector<PositionInfo> ComponentAlternation::first() const {
// firsts come from all our subcomponents in position order. This will
// maintain left-to-right priority order.
vector<PositionInfo> firsts, subfirsts;
for (const auto &c : children) {
subfirsts = c->first();
firsts.insert(firsts.end(), subfirsts.begin(), subfirsts.end());
}
return firsts;
}
vector<PositionInfo> ComponentAlternation::last() const {
vector<PositionInfo> lasts, sublasts;
for (const auto &c : children) {
sublasts = c->last();
lasts.insert(lasts.end(), sublasts.begin(), sublasts.end());
}
return lasts;
}
bool ComponentAlternation::empty(void) const {
// an alternation can be empty if any of its components are empty
for (const auto &c : children) {
if (c->empty()) {
return true;
}
}
return false;
}
void ComponentAlternation::notePositions(GlushkovBuildState &bs) {
u32 pb = bs.getBuilder().numVertices();
for (auto &c : children) {
c->notePositions(bs);
}
recordPosBounds(pb, bs.getBuilder().numVertices());
}
void ComponentAlternation::buildFollowSet(GlushkovBuildState &bs,
const vector<PositionInfo> &lastPos) {
for (auto &c : children) {
c->buildFollowSet(bs, lastPos);
}
}
bool ComponentAlternation::checkEmbeddedStartAnchor(bool at_start) const {
bool rv = at_start;
for (const auto &c : children) {
rv &= c->checkEmbeddedStartAnchor(at_start);
}
return rv;
}
bool ComponentAlternation::checkEmbeddedEndAnchor(bool at_end) const {
bool rv = at_end;
for (const auto &c : children) {
rv &= c->checkEmbeddedEndAnchor(at_end);
}
return rv;
}
bool ComponentAlternation::vacuous_everywhere(void) const {
for (const auto &c : children) {
if (c->vacuous_everywhere()) {
return true;
}
}
return false;
}
void ComponentAlternation::optimise(bool connected_to_sds) {
for (auto &c : children) {
c->optimise(connected_to_sds);
}
}
} // namespace ue2