1 /*
2 * Copyright (c) 2015, Intel Corporation
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * * Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer.
9 * * Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 * * Neither the name of Intel Corporation nor the names of its contributors
13 * may be used to endorse or promote products derived from this software
14 * without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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27 */
28
29 /** \file
30 * \brief Conditional reference.
31 */
32 #include "ComponentCondReference.h"
33 #include "ComponentAlternation.h"
34 #include "ComponentAssertion.h"
35 #include "parse_error.h"
36 #include "position_info.h"
37
38 #include <algorithm>
39 #include <cassert>
40 #include <memory>
41
42 using namespace std;
43
44 namespace ue2 {
45
ComponentCondReference(unsigned ref)46 ComponentCondReference::ComponentCondReference(unsigned ref)
47 : kind(CONDITION_NUMBER), ref_id(ref), hasBothBranches(false) {}
48
ComponentCondReference(const string & name)49 ComponentCondReference::ComponentCondReference(const string &name)
50 : kind(CONDITION_NAME), ref_id(0), ref_name(name), hasBothBranches(false) {}
51
ComponentCondReference(unique_ptr<Component> c)52 ComponentCondReference::ComponentCondReference(unique_ptr<Component> c)
53 : kind(CONDITION_ASSERTION), ref_id(0), assertion(move(c)),
54 hasBothBranches(false) {}
55
~ComponentCondReference()56 ComponentCondReference::~ComponentCondReference() {}
57
ComponentCondReference(const ComponentCondReference & other)58 ComponentCondReference::ComponentCondReference(
59 const ComponentCondReference &other)
60 : ComponentSequence(other), kind(other.kind), ref_id(other.ref_id),
61 ref_name(other.ref_name), hasBothBranches(other.hasBothBranches) {
62 if (kind == CONDITION_ASSERTION) {
63 assert(other.assertion);
64 assertion.reset(other.assertion->clone());
65 } else {
66 assert(!other.assertion);
67 }
68 }
69
clone() const70 ComponentCondReference *ComponentCondReference::clone() const {
71 return new ComponentCondReference(*this);
72 }
73
accept(ComponentVisitor & v)74 Component *ComponentCondReference::accept(ComponentVisitor &v) {
75 Component *c = v.visit(this);
76 if (c != this) {
77 v.post(this);
78 return c;
79 }
80
81 if (kind == CONDITION_ASSERTION) {
82 Component *a = assertion.get();
83 c = assertion->accept(v);
84 if (c != a) {
85 assertion.reset(c);
86 }
87 }
88
89 for (auto i = children.begin(), e = children.end(); i != e; ++i) {
90 Component *child = i->get();
91 c = (*i)->accept(v);
92 if (c != child) {
93 // Child has been replaced (new Component pointer) or we've been
94 // instructed to delete it (null).
95 i->reset(c);
96 }
97 }
98
99 // Remove deleted children.
100 children.erase(remove(children.begin(), children.end(), nullptr),
101 children.end());
102
103 v.post(this);
104 return this;
105 }
106
accept(ConstComponentVisitor & v) const107 void ComponentCondReference::accept(ConstComponentVisitor &v) const {
108 v.pre(*this);
109
110 if (kind == CONDITION_ASSERTION) {
111 assertion->accept(v);
112 v.during(*this); // FIXME: a good idea?
113 }
114
115 for (auto i = children.begin(), e = children.end(); i != e; ++i) {
116 (*i)->accept(v);
117 if (i + 1 != e) {
118 v.during(*this);
119 }
120 }
121
122 v.post(*this);
123 }
124
addAlternation()125 void ComponentCondReference::addAlternation() {
126 if (alternation) {
127 if (ref_name == "DEFINE") {
128 throw LocatedParseError("DEFINE conditional group with more than "
129 "one branch");
130 }
131
132 if (alternation->numBranches() >= 2) {
133 throw LocatedParseError("Conditional with more than two branches");
134 }
135 }
136 hasBothBranches = true;
137 ComponentSequence::addAlternation();
138 }
139
first() const140 vector<PositionInfo> ComponentCondReference::first() const {
141 assert(0);
142 return vector<PositionInfo>();
143 }
144
last() const145 vector<PositionInfo> ComponentCondReference::last() const {
146 assert(0);
147 return vector<PositionInfo>();
148 }
149
empty() const150 bool ComponentCondReference::empty() const { return true; }
151
notePositions(GlushkovBuildState &)152 void ComponentCondReference::notePositions(GlushkovBuildState &) { assert(0); }
153
buildFollowSet(GlushkovBuildState &,const vector<PositionInfo> &)154 void ComponentCondReference::buildFollowSet(GlushkovBuildState &,
155 const vector<PositionInfo> &) {
156 assert(0);
157 }
158
repeatable() const159 bool ComponentCondReference::repeatable() const {
160 // If this assertion has no children (it's an empty sequence, like that
161 // produced by '(?!)') then PCRE would throw a "nothing to repeat" error.
162 // So we do as well.
163 return !children.empty();
164 }
165
166 } // namespace ue2
167