blob: 402278e9bbc834257b9f0d05c539517c2793440c [file] [log] [blame]
/*
* Copyright 2008 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkPtrSet_DEFINED
#define SkPtrSet_DEFINED
#include "SkRefCnt.h"
#include "SkFlattenable.h"
#include "SkTDArray.h"
/**
* Maintains a set of ptrs, assigning each a unique ID [1...N]. Duplicate ptrs
* return the same ID (since its a set). Subclasses can override inPtr()
* and decPtr(). incPtr() is called each time a unique ptr is added ot the
* set. decPtr() is called on each ptr when the set is destroyed or reset.
*/
class SkPtrSet : public SkRefCnt {
public:
/**
* Search for the specified ptr in the set. If it is found, return its
* 32bit ID [1..N], or if not found, return 0. Always returns 0 for nullptr.
*/
uint32_t find(void*) const;
/**
* Add the specified ptr to the set, returning a unique 32bit ID for it
* [1...N]. Duplicate ptrs will return the same ID.
*
* If the ptr is nullptr, it is not added, and 0 is returned.
*/
uint32_t add(void*);
/**
* Return the number of (non-null) ptrs in the set.
*/
int count() const { return fList.count(); }
/**
* Copy the ptrs in the set into the specified array (allocated by the
* caller). The ptrs are assgined to the array based on their corresponding
* ID. e.g. array[ptr.ID - 1] = ptr.
*
* incPtr() and decPtr() are not called during this operation.
*/
void copyToArray(void* array[]) const;
/**
* Call decPtr() on each ptr in the set, and the reset the size of the set
* to 0.
*/
void reset();
/**
* Set iterator.
*/
class Iter {
public:
Iter(const SkPtrSet& set)
: fSet(set)
, fIndex(0) {}
/**
* Return the next ptr in the set or null if the end was reached.
*/
void* next() {
return fIndex < fSet.fList.count() ? fSet.fList[fIndex++].fPtr : nullptr;
}
private:
const SkPtrSet& fSet;
int fIndex;
};
protected:
virtual void incPtr(void*) {}
virtual void decPtr(void*) {}
private:
struct Pair {
void* fPtr; // never nullptr
uint32_t fIndex; // 1...N
};
// we store the ptrs in sorted-order (using Cmp) so that we can efficiently
// detect duplicates when add() is called. Hence we need to store the
// ptr and its ID/fIndex explicitly, since the ptr's position in the array
// is not related to its "index".
SkTDArray<Pair> fList;
static bool Less(const Pair& a, const Pair& b);
typedef SkRefCnt INHERITED;
};
/**
* Templated wrapper for SkPtrSet, just meant to automate typecasting
* parameters to and from void* (which the base class expects).
*/
template <typename T> class SkTPtrSet : public SkPtrSet {
public:
uint32_t find(T ptr) {
return this->INHERITED::find((void*)ptr);
}
uint32_t add(T ptr) {
return this->INHERITED::add((void*)ptr);
}
void copyToArray(T* array) const {
this->INHERITED::copyToArray((void**)array);
}
private:
typedef SkPtrSet INHERITED;
};
/**
* Subclass of SkTPtrSet specialed to call ref() and unref() when the
* base class's incPtr() and decPtr() are called. This makes it a valid owner
* of each ptr, which is released when the set is reset or destroyed.
*/
class SkRefCntSet : public SkTPtrSet<SkRefCnt*> {
public:
virtual ~SkRefCntSet();
protected:
// overrides
virtual void incPtr(void*);
virtual void decPtr(void*);
};
class SkFactorySet : public SkTPtrSet<SkFlattenable::Factory> {};
/**
* Similar to SkFactorySet, but only allows Factorys that have registered names.
* Also has a function to return the next added Factory's name.
*/
class SkNamedFactorySet : public SkRefCnt {
public:
SkNamedFactorySet();
/**
* Find the specified Factory in the set. If it is not already in the set,
* and has registered its name, add it to the set, and return its index.
* If the Factory has no registered name, return 0.
*/
uint32_t find(SkFlattenable::Factory);
/**
* If new Factorys have been added to the set, return the name of the first
* Factory added after the Factory name returned by the last call to this
* function.
*/
const char* getNextAddedFactoryName();
private:
int fNextAddedFactory;
SkFactorySet fFactorySet;
SkTDArray<const char*> fNames;
typedef SkRefCnt INHERITED;
};
#endif