| /* |
| * Copyright 2016 The WebRTC Project Authors. All rights reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "webrtc/base/copyonwritebuffer.h" |
| |
| namespace rtc { |
| |
| CopyOnWriteBuffer::CopyOnWriteBuffer() { |
| RTC_DCHECK(IsConsistent()); |
| } |
| |
| CopyOnWriteBuffer::CopyOnWriteBuffer(const CopyOnWriteBuffer& buf) |
| : buffer_(buf.buffer_) { |
| } |
| |
| CopyOnWriteBuffer::CopyOnWriteBuffer(CopyOnWriteBuffer&& buf) |
| : buffer_(std::move(buf.buffer_)) { |
| } |
| |
| CopyOnWriteBuffer::CopyOnWriteBuffer(size_t size) |
| : buffer_(size > 0 ? new RefCountedObject<Buffer>(size) : nullptr) { |
| RTC_DCHECK(IsConsistent()); |
| } |
| |
| CopyOnWriteBuffer::CopyOnWriteBuffer(size_t size, size_t capacity) |
| : buffer_(size > 0 || capacity > 0 |
| ? new RefCountedObject<Buffer>(size, capacity) |
| : nullptr) { |
| RTC_DCHECK(IsConsistent()); |
| } |
| |
| CopyOnWriteBuffer::~CopyOnWriteBuffer() = default; |
| |
| bool CopyOnWriteBuffer::operator==(const CopyOnWriteBuffer& buf) const { |
| // Must either use the same buffer internally or have the same contents. |
| RTC_DCHECK(IsConsistent()); |
| RTC_DCHECK(buf.IsConsistent()); |
| return buffer_.get() == buf.buffer_.get() || |
| (buffer_.get() && buf.buffer_.get() && |
| *buffer_.get() == *buf.buffer_.get()); |
| } |
| |
| void CopyOnWriteBuffer::SetSize(size_t size) { |
| RTC_DCHECK(IsConsistent()); |
| if (!buffer_) { |
| if (size > 0) { |
| buffer_ = new RefCountedObject<Buffer>(size); |
| } |
| RTC_DCHECK(IsConsistent()); |
| return; |
| } |
| |
| // Clone data if referenced. |
| if (!buffer_->HasOneRef()) { |
| buffer_ = new RefCountedObject<Buffer>( |
| buffer_->data(), |
| std::min(buffer_->size(), size), |
| std::max(buffer_->capacity(), size)); |
| } |
| buffer_->SetSize(size); |
| RTC_DCHECK(IsConsistent()); |
| } |
| |
| void CopyOnWriteBuffer::EnsureCapacity(size_t capacity) { |
| RTC_DCHECK(IsConsistent()); |
| if (!buffer_) { |
| if (capacity > 0) { |
| buffer_ = new RefCountedObject<Buffer>(0, capacity); |
| } |
| RTC_DCHECK(IsConsistent()); |
| return; |
| } else if (capacity <= buffer_->capacity()) { |
| return; |
| } |
| |
| CloneDataIfReferenced(std::max(buffer_->capacity(), capacity)); |
| buffer_->EnsureCapacity(capacity); |
| RTC_DCHECK(IsConsistent()); |
| } |
| |
| void CopyOnWriteBuffer::Clear() { |
| if (!buffer_) |
| return; |
| |
| if (buffer_->HasOneRef()) { |
| buffer_->Clear(); |
| } else { |
| buffer_ = new RefCountedObject<Buffer>(0, buffer_->capacity()); |
| } |
| RTC_DCHECK(IsConsistent()); |
| } |
| |
| void CopyOnWriteBuffer::CloneDataIfReferenced(size_t new_capacity) { |
| if (buffer_->HasOneRef()) { |
| return; |
| } |
| |
| buffer_ = new RefCountedObject<Buffer>(buffer_->data(), buffer_->size(), |
| new_capacity); |
| RTC_DCHECK(IsConsistent()); |
| } |
| |
| |
| |
| } // namespace rtc |