1 // Copyright 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "cc/resources/shared_bitmap.h" 6 7 #include "base/logging.h" 8 #include "base/numerics/safe_math.h" 9 #include "base/rand_util.h" 10 11 namespace cc { 12 13 SharedBitmap::SharedBitmap( 14 base::SharedMemory* memory, 15 const SharedBitmapId& id, 16 const base::Callback<void(SharedBitmap* bitmap)>& free_callback) 17 : memory_(memory), 18 pixels_(static_cast<uint8*>(memory_->memory())), 19 id_(id), 20 free_callback_(free_callback) { 21 } 22 23 SharedBitmap::SharedBitmap( 24 uint8* pixels, 25 const SharedBitmapId& id, 26 const base::Callback<void(SharedBitmap* bitmap)>& free_callback) 27 : memory_(NULL), pixels_(pixels), id_(id), free_callback_(free_callback) { 28 } 29 30 SharedBitmap::~SharedBitmap() { free_callback_.Run(this); } 31 32 // static 33 bool SharedBitmap::SizeInBytes(const gfx::Size& size, size_t* size_in_bytes) { 34 if (size.IsEmpty()) 35 return false; 36 base::CheckedNumeric<size_t> s = 4; 37 s *= size.width(); 38 s *= size.height(); 39 if (!s.IsValid()) 40 return false; 41 *size_in_bytes = s.ValueOrDie(); 42 return true; 43 } 44 45 // static 46 size_t SharedBitmap::CheckedSizeInBytes(const gfx::Size& size) { 47 CHECK(!size.IsEmpty()); 48 base::CheckedNumeric<size_t> s = 4; 49 s *= size.width(); 50 s *= size.height(); 51 return s.ValueOrDie(); 52 } 53 54 // static 55 size_t SharedBitmap::UncheckedSizeInBytes(const gfx::Size& size) { 56 DCHECK(VerifySizeInBytes(size)); 57 size_t s = 4; 58 s *= size.width(); 59 s *= size.height(); 60 return s; 61 } 62 63 // static 64 bool SharedBitmap::VerifySizeInBytes(const gfx::Size& size) { 65 if (size.IsEmpty()) 66 return false; 67 base::CheckedNumeric<size_t> s = 4; 68 s *= size.width(); 69 s *= size.height(); 70 return s.IsValid(); 71 } 72 73 // static 74 SharedBitmapId SharedBitmap::GenerateId() { 75 SharedBitmapId id; 76 // Needs cryptographically-secure random numbers. 77 base::RandBytes(id.name, sizeof(id.name)); 78 return id; 79 } 80 81 } // namespace cc 82
