reed | 9d93c2e | 2014-10-08 05:17:12 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2014 Google Inc. |
| 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 | #ifndef SkCachedData_DEFINED |
| 9 | #define SkCachedData_DEFINED |
| 10 | |
mtklein | 1b24933 | 2015-07-07 12:21:21 -0700 | [diff] [blame^] | 11 | #include "SkMutex.h" |
reed | 9d93c2e | 2014-10-08 05:17:12 -0700 | [diff] [blame] | 12 | |
| 13 | class SkDiscardableMemory; |
| 14 | |
| 15 | class SkCachedData : ::SkNoncopyable { |
| 16 | public: |
| 17 | SkCachedData(void* mallocData, size_t size); |
| 18 | SkCachedData(size_t size, SkDiscardableMemory*); |
| 19 | virtual ~SkCachedData(); |
| 20 | |
| 21 | size_t size() const { return fSize; } |
| 22 | const void* data() const { return fData; } |
| 23 | |
| 24 | void* writable_data() { return fData; } |
| 25 | |
| 26 | void ref() const { this->internalRef(false); } |
| 27 | void unref() const { this->internalUnref(false); } |
| 28 | |
| 29 | int testing_only_getRefCnt() const { return fRefCnt; } |
| 30 | bool testing_only_isLocked() const { return fIsLocked; } |
| 31 | bool testing_only_isInCache() const { return fInCache; } |
| 32 | |
| 33 | protected: |
| 34 | // called when fData changes. could be NULL. |
| 35 | virtual void onDataChange(void* oldData, void* newData) {} |
| 36 | |
| 37 | private: |
| 38 | SkMutex fMutex; // could use a pool of these... |
| 39 | |
| 40 | enum StorageType { |
| 41 | kDiscardableMemory_StorageType, |
| 42 | kMalloc_StorageType |
| 43 | }; |
| 44 | |
| 45 | union { |
| 46 | SkDiscardableMemory* fDM; |
| 47 | void* fMalloc; |
| 48 | } fStorage; |
| 49 | void* fData; |
| 50 | size_t fSize; |
| 51 | int fRefCnt; // low-bit means we're owned by the cache |
| 52 | StorageType fStorageType; |
| 53 | bool fInCache; |
| 54 | bool fIsLocked; |
| 55 | |
| 56 | void internalRef(bool fromCache) const; |
| 57 | void internalUnref(bool fromCache) const; |
| 58 | |
| 59 | void inMutexRef(bool fromCache); |
| 60 | bool inMutexUnref(bool fromCache); // returns true if we should delete "this" |
| 61 | void inMutexLock(); |
| 62 | void inMutexUnlock(); |
| 63 | |
| 64 | // called whenever our fData might change (lock or unlock) |
| 65 | void setData(void* newData) { |
| 66 | if (newData != fData) { |
| 67 | // notify our subclasses of the change |
| 68 | this->onDataChange(fData, newData); |
| 69 | fData = newData; |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | class AutoMutexWritable; |
| 74 | |
| 75 | public: |
| 76 | #ifdef SK_DEBUG |
| 77 | void validate() const; |
| 78 | #else |
| 79 | void validate() const {} |
| 80 | #endif |
mtklein | 1b24933 | 2015-07-07 12:21:21 -0700 | [diff] [blame^] | 81 | |
reed | 9d93c2e | 2014-10-08 05:17:12 -0700 | [diff] [blame] | 82 | /* |
| 83 | * Attaching a data to to a SkResourceCache (only one at a time) enables the data to be |
| 84 | * unlocked when the cache is the only owner, thus freeing it to be purged (assuming the |
| 85 | * data is backed by a SkDiscardableMemory). |
| 86 | * |
| 87 | * When attached, it also automatically attempts to "lock" the data when the first client |
| 88 | * ref's the data (typically from a find(key, visitor) call). |
| 89 | * |
| 90 | * Thus the data will always be "locked" when a non-cache has a ref on it (whether or not |
| 91 | * the lock succeeded to recover the memory -- check data() to see if it is NULL). |
| 92 | */ |
| 93 | |
| 94 | /* |
| 95 | * Call when adding this instance to a SkResourceCache::Rec subclass |
| 96 | * (typically in the Rec's constructor). |
| 97 | */ |
| 98 | void attachToCacheAndRef() const { this->internalRef(true); } |
| 99 | |
| 100 | /* |
| 101 | * Call when removing this instance from a SkResourceCache::Rec subclass |
| 102 | * (typically in the Rec's destructor). |
| 103 | */ |
| 104 | void detachFromCacheAndUnref() const { this->internalUnref(true); } |
| 105 | }; |
| 106 | |
| 107 | #endif |