1/*
2 * Copyright 2008 The Android Open Source Project
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8
9#ifndef SkPtrSet_DEFINED
10#define SkPtrSet_DEFINED
11
12#include "include/core/SkFlattenable.h"
13#include "include/core/SkRefCnt.h"
14#include "include/private/SkTDArray.h"
15
16/**
17 * Maintains a set of ptrs, assigning each a unique ID [1...N]. Duplicate ptrs
18 * return the same ID (since its a set). Subclasses can override inPtr()
19 * and decPtr(). incPtr() is called each time a unique ptr is added ot the
20 * set. decPtr() is called on each ptr when the set is destroyed or reset.
21 */
22class SkPtrSet : public SkRefCnt {
23public:
24
25
26 /**
27 * Search for the specified ptr in the set. If it is found, return its
28 * 32bit ID [1..N], or if not found, return 0. Always returns 0 for nullptr.
29 */
30 uint32_t find(void*) const;
31
32 /**
33 * Add the specified ptr to the set, returning a unique 32bit ID for it
34 * [1...N]. Duplicate ptrs will return the same ID.
35 *
36 * If the ptr is nullptr, it is not added, and 0 is returned.
37 */
38 uint32_t add(void*);
39
40 /**
41 * Return the number of (non-null) ptrs in the set.
42 */
43 int count() const { return fList.count(); }
44
45 /**
46 * Copy the ptrs in the set into the specified array (allocated by the
47 * caller). The ptrs are assgined to the array based on their corresponding
48 * ID. e.g. array[ptr.ID - 1] = ptr.
49 *
50 * incPtr() and decPtr() are not called during this operation.
51 */
52 void copyToArray(void* array[]) const;
53
54 /**
55 * Call decPtr() on each ptr in the set, and the reset the size of the set
56 * to 0.
57 */
58 void reset();
59
60 /**
61 * Set iterator.
62 */
63 class Iter {
64 public:
65 Iter(const SkPtrSet& set)
66 : fSet(set)
67 , fIndex(0) {}
68
69 /**
70 * Return the next ptr in the set or null if the end was reached.
71 */
72 void* next() {
73 return fIndex < fSet.fList.count() ? fSet.fList[fIndex++].fPtr : nullptr;
74 }
75
76 private:
77 const SkPtrSet& fSet;
78 int fIndex;
79 };
80
81protected:
82 virtual void incPtr(void*) {}
83 virtual void decPtr(void*) {}
84
85private:
86 struct Pair {
87 void* fPtr; // never nullptr
88 uint32_t fIndex; // 1...N
89 };
90
91 // we store the ptrs in sorted-order (using Cmp) so that we can efficiently
92 // detect duplicates when add() is called. Hence we need to store the
93 // ptr and its ID/fIndex explicitly, since the ptr's position in the array
94 // is not related to its "index".
95 SkTDArray<Pair> fList;
96
97 static bool Less(const Pair& a, const Pair& b);
98
99 typedef SkRefCnt INHERITED;
100};
101
102/**
103 * Templated wrapper for SkPtrSet, just meant to automate typecasting
104 * parameters to and from void* (which the base class expects).
105 */
106template <typename T> class SkTPtrSet : public SkPtrSet {
107public:
108 uint32_t find(T ptr) {
109 return this->INHERITED::find((void*)ptr);
110 }
111 uint32_t add(T ptr) {
112 return this->INHERITED::add((void*)ptr);
113 }
114
115 void copyToArray(T* array) const {
116 this->INHERITED::copyToArray((void**)array);
117 }
118
119private:
120 typedef SkPtrSet INHERITED;
121};
122
123/**
124 * Subclass of SkTPtrSet specialed to call ref() and unref() when the
125 * base class's incPtr() and decPtr() are called. This makes it a valid owner
126 * of each ptr, which is released when the set is reset or destroyed.
127 */
128class SkRefCntSet : public SkTPtrSet<SkRefCnt*> {
129public:
130 ~SkRefCntSet() override;
131
132protected:
133 // overrides
134 void incPtr(void*) override;
135 void decPtr(void*) override;
136};
137
138class SkFactorySet : public SkTPtrSet<SkFlattenable::Factory> {};
139
140/**
141 * Similar to SkFactorySet, but only allows Factorys that have registered names.
142 * Also has a function to return the next added Factory's name.
143 */
144class SkNamedFactorySet : public SkRefCnt {
145public:
146
147
148 SkNamedFactorySet();
149
150 /**
151 * Find the specified Factory in the set. If it is not already in the set,
152 * and has registered its name, add it to the set, and return its index.
153 * If the Factory has no registered name, return 0.
154 */
155 uint32_t find(SkFlattenable::Factory);
156
157 /**
158 * If new Factorys have been added to the set, return the name of the first
159 * Factory added after the Factory name returned by the last call to this
160 * function.
161 */
162 const char* getNextAddedFactoryName();
163private:
164 int fNextAddedFactory;
165 SkFactorySet fFactorySet;
166 SkTDArray<const char*> fNames;
167
168 typedef SkRefCnt INHERITED;
169};
170
171#endif
172