epoger@google.com | ec3ed6a | 2011-07-28 14:26:00 +0000 | [diff] [blame^] | 1 | |
| 2 | /* |
| 3 | * Copyright 2006 The Android Open Source Project |
| 4 | * |
| 5 | * Use of this source code is governed by a BSD-style license that can be |
| 6 | * found in the LICENSE file. |
| 7 | */ |
| 8 | |
reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame] | 9 | |
| 10 | #ifndef SkRegionPriv_DEFINED |
| 11 | #define SkRegionPriv_DEFINED |
| 12 | |
| 13 | #include "SkRegion.h" |
| 14 | #include "SkThread.h" |
| 15 | |
| 16 | #define assert_sentinel(value, isSentinel) \ |
| 17 | SkASSERT(((value) == SkRegion::kRunTypeSentinel) == isSentinel) |
| 18 | |
| 19 | //SkDEBUGCODE(extern int32_t gRgnAllocCounter;) |
| 20 | |
| 21 | struct SkRegion::RunHead { |
| 22 | int32_t fRefCnt; |
| 23 | int32_t fRunCount; |
| 24 | |
| 25 | static RunHead* Alloc(int count) |
| 26 | { |
| 27 | //SkDEBUGCODE(sk_atomic_inc(&gRgnAllocCounter);) |
| 28 | //SkDEBUGF(("************** gRgnAllocCounter::alloc %d\n", gRgnAllocCounter)); |
| 29 | |
| 30 | SkASSERT(count >= SkRegion::kRectRegionRuns); |
| 31 | |
| 32 | RunHead* head = (RunHead*)sk_malloc_throw(sizeof(RunHead) + count * sizeof(RunType)); |
| 33 | head->fRefCnt = 1; |
| 34 | head->fRunCount = count; |
| 35 | return head; |
| 36 | } |
| 37 | |
| 38 | bool isComplex() const |
| 39 | { |
| 40 | return this != SkRegion_gEmptyRunHeadPtr && this != SkRegion_gRectRunHeadPtr; |
| 41 | } |
| 42 | |
| 43 | SkRegion::RunType* writable_runs() |
| 44 | { |
| 45 | SkASSERT(this->isComplex()); |
| 46 | SkASSERT(fRefCnt == 1); |
| 47 | return (SkRegion::RunType*)(this + 1); |
| 48 | } |
| 49 | const SkRegion::RunType* readonly_runs() const |
| 50 | { |
| 51 | SkASSERT(this->isComplex()); |
| 52 | return (const SkRegion::RunType*)(this + 1); |
| 53 | } |
| 54 | |
| 55 | RunHead* ensureWritable() |
| 56 | { |
| 57 | SkASSERT(this->isComplex()); |
| 58 | |
| 59 | RunHead* writable = this; |
| 60 | if (fRefCnt > 1) |
| 61 | { |
| 62 | // We need to alloc & copy the current region before we call |
| 63 | // sk_atomic_dec because it could be freed in the meantime, |
| 64 | // otherwise. |
| 65 | writable = Alloc(fRunCount); |
| 66 | memcpy(writable->writable_runs(), this->readonly_runs(), |
| 67 | fRunCount * sizeof(RunType)); |
| 68 | |
| 69 | // fRefCount might have changed since we last checked. |
| 70 | // If we own the last reference at this point, we need to |
| 71 | // free the memory. |
| 72 | if (sk_atomic_dec(&fRefCnt) == 1) |
| 73 | { |
| 74 | sk_free(this); |
| 75 | } |
| 76 | } |
| 77 | return writable; |
| 78 | } |
| 79 | }; |
| 80 | |
| 81 | #endif |