reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame^] | 1 | /* libs/corecg/SkRegionPriv.h |
| 2 | ** |
| 3 | ** Copyright 2006, The Android Open Source Project |
| 4 | ** |
| 5 | ** Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | ** you may not use this file except in compliance with the License. |
| 7 | ** You may obtain a copy of the License at |
| 8 | ** |
| 9 | ** http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | ** |
| 11 | ** Unless required by applicable law or agreed to in writing, software |
| 12 | ** distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | ** See the License for the specific language governing permissions and |
| 15 | ** limitations under the License. |
| 16 | */ |
| 17 | |
| 18 | #ifndef SkRegionPriv_DEFINED |
| 19 | #define SkRegionPriv_DEFINED |
| 20 | |
| 21 | #include "SkRegion.h" |
| 22 | #include "SkThread.h" |
| 23 | |
| 24 | #define assert_sentinel(value, isSentinel) \ |
| 25 | SkASSERT(((value) == SkRegion::kRunTypeSentinel) == isSentinel) |
| 26 | |
| 27 | //SkDEBUGCODE(extern int32_t gRgnAllocCounter;) |
| 28 | |
| 29 | struct SkRegion::RunHead { |
| 30 | int32_t fRefCnt; |
| 31 | int32_t fRunCount; |
| 32 | |
| 33 | static RunHead* Alloc(int count) |
| 34 | { |
| 35 | //SkDEBUGCODE(sk_atomic_inc(&gRgnAllocCounter);) |
| 36 | //SkDEBUGF(("************** gRgnAllocCounter::alloc %d\n", gRgnAllocCounter)); |
| 37 | |
| 38 | SkASSERT(count >= SkRegion::kRectRegionRuns); |
| 39 | |
| 40 | RunHead* head = (RunHead*)sk_malloc_throw(sizeof(RunHead) + count * sizeof(RunType)); |
| 41 | head->fRefCnt = 1; |
| 42 | head->fRunCount = count; |
| 43 | return head; |
| 44 | } |
| 45 | |
| 46 | bool isComplex() const |
| 47 | { |
| 48 | return this != SkRegion_gEmptyRunHeadPtr && this != SkRegion_gRectRunHeadPtr; |
| 49 | } |
| 50 | |
| 51 | SkRegion::RunType* writable_runs() |
| 52 | { |
| 53 | SkASSERT(this->isComplex()); |
| 54 | SkASSERT(fRefCnt == 1); |
| 55 | return (SkRegion::RunType*)(this + 1); |
| 56 | } |
| 57 | const SkRegion::RunType* readonly_runs() const |
| 58 | { |
| 59 | SkASSERT(this->isComplex()); |
| 60 | return (const SkRegion::RunType*)(this + 1); |
| 61 | } |
| 62 | |
| 63 | RunHead* ensureWritable() |
| 64 | { |
| 65 | SkASSERT(this->isComplex()); |
| 66 | |
| 67 | RunHead* writable = this; |
| 68 | if (fRefCnt > 1) |
| 69 | { |
| 70 | // We need to alloc & copy the current region before we call |
| 71 | // sk_atomic_dec because it could be freed in the meantime, |
| 72 | // otherwise. |
| 73 | writable = Alloc(fRunCount); |
| 74 | memcpy(writable->writable_runs(), this->readonly_runs(), |
| 75 | fRunCount * sizeof(RunType)); |
| 76 | |
| 77 | // fRefCount might have changed since we last checked. |
| 78 | // If we own the last reference at this point, we need to |
| 79 | // free the memory. |
| 80 | if (sk_atomic_dec(&fRefCnt) == 1) |
| 81 | { |
| 82 | sk_free(this); |
| 83 | } |
| 84 | } |
| 85 | return writable; |
| 86 | } |
| 87 | }; |
| 88 | |
| 89 | #endif |