joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 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 GrNonAtomicRef_DEFINED |
| 9 | #define GrNonAtomicRef_DEFINED |
| 10 | |
Mike Klein | c0bd9f9 | 2019-04-23 12:05:21 -0500 | [diff] [blame] | 11 | #include "include/core/SkRefCnt.h" |
| 12 | #include "include/private/SkNoncopyable.h" |
| 13 | #include "include/private/SkTArray.h" |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 14 | |
| 15 | /** |
Greg Daniel | bdf12ad | 2018-10-12 09:31:11 -0400 | [diff] [blame] | 16 | * A simple non-atomic ref used in the GrBackendApi when we don't want to pay for the overhead of a |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 17 | * threadsafe ref counted object |
| 18 | */ |
cdalton | 4833f39 | 2016-02-02 22:46:16 -0800 | [diff] [blame] | 19 | template<typename TSubclass> class GrNonAtomicRef : public SkNoncopyable { |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 20 | public: |
| 21 | GrNonAtomicRef() : fRefCnt(1) {} |
cdalton | 4833f39 | 2016-02-02 22:46:16 -0800 | [diff] [blame] | 22 | |
| 23 | #ifdef SK_DEBUG |
| 24 | ~GrNonAtomicRef() { |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 25 | // fRefCnt can be one when a subclass is created statically |
| 26 | SkASSERT((0 == fRefCnt || 1 == fRefCnt)); |
| 27 | // Set to invalid values. |
cdalton | 4833f39 | 2016-02-02 22:46:16 -0800 | [diff] [blame] | 28 | fRefCnt = -10; |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 29 | } |
cdalton | 4833f39 | 2016-02-02 22:46:16 -0800 | [diff] [blame] | 30 | #endif |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 31 | |
csmartdalton | 28341fa | 2016-08-17 10:00:21 -0700 | [diff] [blame] | 32 | bool unique() const { return 1 == fRefCnt; } |
| 33 | |
Brian Salomon | a036f0d | 2019-08-29 11:16:04 -0400 | [diff] [blame] | 34 | // We allow this getter because this type is not thread-safe, meaning only one thread should |
| 35 | // have ownership and be manipulating the ref count or querying this. |
| 36 | int refCnt() const { return fRefCnt; } |
| 37 | |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 38 | void ref() const { |
| 39 | // Once the ref cnt reaches zero it should never be ref'ed again. |
| 40 | SkASSERT(fRefCnt > 0); |
| 41 | ++fRefCnt; |
| 42 | } |
| 43 | |
| 44 | void unref() const { |
| 45 | SkASSERT(fRefCnt > 0); |
| 46 | --fRefCnt; |
| 47 | if (0 == fRefCnt) { |
cdalton | 4833f39 | 2016-02-02 22:46:16 -0800 | [diff] [blame] | 48 | GrTDeleteNonAtomicRef(static_cast<const TSubclass*>(this)); |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 49 | return; |
| 50 | } |
| 51 | } |
| 52 | |
| 53 | private: |
| 54 | mutable int32_t fRefCnt; |
| 55 | |
| 56 | typedef SkNoncopyable INHERITED; |
| 57 | }; |
| 58 | |
cdalton | 4833f39 | 2016-02-02 22:46:16 -0800 | [diff] [blame] | 59 | template<typename T> inline void GrTDeleteNonAtomicRef(const T* ref) { |
| 60 | delete ref; |
| 61 | } |
| 62 | |
joshualitt | 2419b36 | 2015-07-13 09:29:42 -0700 | [diff] [blame] | 63 | #endif |