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 |
23 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
24 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
25 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
26 | * POSSIBILITY OF SUCH DAMAGE. |
27 | */ |
28 | |
29 | /** \file |
30 | * \brief Lookahead/lookbehind zero-width assertions. |
31 | */ |
32 | #include "ComponentAssertion.h" |
33 | #include "buildstate.h" |
34 | #include "position.h" |
35 | #include "position_info.h" |
36 | #include "ue2common.h" |
37 | |
38 | #include <cassert> |
39 | #include <algorithm> |
40 | |
41 | using namespace std; |
42 | |
43 | namespace ue2 { |
44 | |
45 | ComponentAssertion::ComponentAssertion(enum Direction dir, enum Sense sense) |
46 | : m_dir(dir), m_sense(sense) {} |
47 | |
48 | ComponentAssertion::~ComponentAssertion() { } |
49 | |
50 | ComponentAssertion *ComponentAssertion::clone() const { |
51 | return new ComponentAssertion(*this); |
52 | } |
53 | |
54 | Component * ComponentAssertion::accept(ComponentVisitor &v) { |
55 | Component *c = v.visit(this); |
56 | if (c != this) { |
57 | v.post(this); |
58 | return c; |
59 | } |
60 | |
61 | for (auto i = children.begin(), e = children.end(); i != e; ++i) { |
62 | Component *child = i->get(); |
63 | c = (*i)->accept(v); |
64 | if (c != child) { |
65 | // Child has been replaced (new Component pointer) or we've been |
66 | // instructed to delete it (null). |
67 | i->reset(c); |
68 | } |
69 | } |
70 | |
71 | // Remove deleted children. |
72 | children.erase(remove(children.begin(), children.end(), nullptr), |
73 | children.end()); |
74 | |
75 | v.post(this); |
76 | return this; |
77 | } |
78 | |
79 | void ComponentAssertion::accept(ConstComponentVisitor &v) const { |
80 | v.pre(*this); |
81 | for (auto i = children.begin(), e = children.end(); i != e; ++i) { |
82 | (*i)->accept(v); |
83 | if (i + 1 != e) { |
84 | v.during(*this); |
85 | } |
86 | } |
87 | |
88 | v.post(*this); |
89 | } |
90 | |
91 | vector<PositionInfo> ComponentAssertion::first() const { |
92 | assert(0); |
93 | return vector<PositionInfo>(); |
94 | } |
95 | |
96 | vector<PositionInfo> ComponentAssertion::last() const { |
97 | assert(0); |
98 | return vector<PositionInfo>(); |
99 | } |
100 | |
101 | bool ComponentAssertion::empty() const { |
102 | return true; |
103 | } |
104 | |
105 | void ComponentAssertion::notePositions(GlushkovBuildState &) { |
106 | assert(0); |
107 | } |
108 | |
109 | void ComponentAssertion::buildFollowSet(GlushkovBuildState &, |
110 | const vector<PositionInfo> &) { |
111 | assert(0); |
112 | } |
113 | |
114 | bool ComponentAssertion::repeatable() const { |
115 | // If this assertion has no children (it's an empty sequence, like that |
116 | // produced by '(?!)') then PCRE would throw a "nothing to repeat" error. |
117 | // So we do as well. |
118 | return !children.empty(); |
119 | } |
120 | |
121 | } // namespace ue2 |
122 | |