| /* |
| * Copyright 2013 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef SkDiscardableMemory_DEFINED |
| #define SkDiscardableMemory_DEFINED |
| |
| #include "include/core/SkRefCnt.h" |
| #include "include/core/SkTypes.h" |
| |
| /** |
| * Interface for discardable memory. Implementation is provided by the |
| * embedder. |
| */ |
| class SK_API SkDiscardableMemory { |
| public: |
| /** |
| * Factory method that creates, initializes and locks an SkDiscardableMemory |
| * object. If either of these steps fails, a nullptr pointer will be returned. |
| */ |
| static SkDiscardableMemory* Create(size_t bytes); |
| |
| /** |
| * Factory class that creates, initializes and locks an SkDiscardableMemory |
| * object. If either of these steps fails, a nullptr pointer will be returned. |
| */ |
| class Factory : public SkRefCnt { |
| public: |
| virtual SkDiscardableMemory* create(size_t bytes) = 0; |
| private: |
| typedef SkRefCnt INHERITED; |
| }; |
| |
| /** Must not be called while locked. |
| */ |
| virtual ~SkDiscardableMemory() {} |
| |
| /** |
| * Locks the memory, prevent it from being discarded. Once locked. you may |
| * obtain a pointer to that memory using the data() method. |
| * |
| * lock() may return false, indicating that the underlying memory was |
| * discarded and that the lock failed. |
| * |
| * Nested calls to lock are not allowed. |
| */ |
| virtual bool SK_WARN_UNUSED_RESULT lock() = 0; |
| |
| /** |
| * Returns the current pointer for the discardable memory. This call is ONLY |
| * valid when the discardable memory object is locked. |
| */ |
| virtual void* data() = 0; |
| |
| /** |
| * Unlock the memory so that it can be purged by the system. Must be called |
| * after every successful lock call. |
| */ |
| virtual void unlock() = 0; |
| }; |
| |
| #endif |