1 /* libs/graphics/sgl/SkMask.cpp 2 ** 3 ** Copyright 2007, 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 #include "Sk64.h" 19 #include "SkMask.h" 20 21 /** returns the product if it is positive and fits in 31 bits. Otherwise this 22 returns 0. 23 */ 24 static int32_t safeMul32(int32_t a, int32_t b) { 25 Sk64 size; 26 size.setMul(a, b); 27 if (size.is32() && size.isPos()) { 28 return size.get32(); 29 } 30 return 0; 31 } 32 33 size_t SkMask::computeImageSize() const { 34 return safeMul32(fBounds.height(), fRowBytes); 35 } 36 37 size_t SkMask::computeTotalImageSize() const { 38 size_t size = this->computeImageSize(); 39 if (fFormat == SkMask::k3D_Format) { 40 size = safeMul32(size, 3); 41 } 42 return size; 43 } 44 45 /** We explicitly use this allocator for SkBimap pixels, so that we can 46 freely assign memory allocated by one class to the other. 47 */ 48 uint8_t* SkMask::AllocImage(size_t size) { 49 return (uint8_t*)sk_malloc_throw(SkAlign4(size)); 50 } 51 52 /** We explicitly use this allocator for SkBimap pixels, so that we can 53 freely assign memory allocated by one class to the other. 54 */ 55 void SkMask::FreeImage(void* image) { 56 sk_free(image); 57 } 58 59
