| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "cobalt/speech/chunked_byte_buffer.h" |
| |
| #include <algorithm> |
| #include <utility> |
| |
| #include "base/basictypes.h" |
| #include "base/logging.h" |
| |
| namespace { |
| |
| static const size_t kHeaderLength = sizeof(uint32_t); |
| |
| COMPILE_ASSERT(sizeof(size_t) >= kHeaderLength, |
| chunked_byte_buffer_not_supported_on_this_architecture); |
| |
| uint32_t ReadBigEndian32(const uint8_t* buffer) { |
| return (static_cast<uint32_t>(buffer[3])) | |
| (static_cast<uint32_t>(buffer[2]) << 8) | |
| (static_cast<uint32_t>(buffer[1]) << 16) | |
| (static_cast<uint32_t>(buffer[0]) << 24); |
| } |
| |
| } // namespace |
| |
| namespace cobalt { |
| namespace speech { |
| |
| ChunkedByteBuffer::ChunkedByteBuffer() |
| : partial_chunk_(new Chunk()), |
| total_bytes_stored_(0) { |
| } |
| |
| ChunkedByteBuffer::~ChunkedByteBuffer() { |
| Clear(); |
| } |
| |
| void ChunkedByteBuffer::Append(const uint8_t* start, size_t length) { |
| size_t remaining_bytes = length; |
| const uint8_t* next_data = start; |
| |
| while (remaining_bytes > 0) { |
| DCHECK(partial_chunk_ != NULL); |
| size_t insert_length = 0; |
| bool header_completed = false; |
| bool content_completed = false; |
| std::vector<uint8_t>* insert_target; |
| |
| if (partial_chunk_->header.size() < kHeaderLength) { |
| const size_t bytes_to_complete_header = |
| kHeaderLength - partial_chunk_->header.size(); |
| insert_length = std::min(bytes_to_complete_header, remaining_bytes); |
| insert_target = &partial_chunk_->header; |
| header_completed = (remaining_bytes >= bytes_to_complete_header); |
| } else { |
| DCHECK_LT(partial_chunk_->content->size(), |
| partial_chunk_->ExpectedContentLength()); |
| const size_t bytes_to_complete_chunk = |
| partial_chunk_->ExpectedContentLength() - |
| partial_chunk_->content->size(); |
| insert_length = std::min(bytes_to_complete_chunk, remaining_bytes); |
| insert_target = partial_chunk_->content.get(); |
| content_completed = (remaining_bytes >= bytes_to_complete_chunk); |
| } |
| |
| DCHECK_GT(insert_length, 0U); |
| DCHECK_LE(insert_length, remaining_bytes); |
| DCHECK_LE(next_data + insert_length, start + length); |
| insert_target->insert(insert_target->end(), |
| next_data, |
| next_data + insert_length); |
| next_data += insert_length; |
| remaining_bytes -= insert_length; |
| |
| if (header_completed) { |
| DCHECK_EQ(partial_chunk_->header.size(), kHeaderLength); |
| if (partial_chunk_->ExpectedContentLength() == 0) { |
| // Handle zero-byte chunks. |
| chunks_.push_back(partial_chunk_.release()); |
| partial_chunk_.reset(new Chunk()); |
| } else { |
| partial_chunk_->content->reserve( |
| partial_chunk_->ExpectedContentLength()); |
| } |
| } else if (content_completed) { |
| DCHECK_EQ(partial_chunk_->content->size(), |
| partial_chunk_->ExpectedContentLength()); |
| chunks_.push_back(partial_chunk_.release()); |
| partial_chunk_.reset(new Chunk()); |
| } |
| } |
| DCHECK_EQ(next_data, start + length); |
| total_bytes_stored_ += length; |
| } |
| |
| void ChunkedByteBuffer::Append(const std::string& string) { |
| Append(reinterpret_cast<const uint8_t*>(string.data()), string.size()); |
| } |
| |
| bool ChunkedByteBuffer::HasChunks() const { |
| return !chunks_.empty(); |
| } |
| |
| scoped_ptr<std::vector<uint8_t> > ChunkedByteBuffer::PopChunk() { |
| if (chunks_.empty()) |
| return scoped_ptr<std::vector<uint8_t> >().Pass(); |
| scoped_ptr<Chunk> chunk(*chunks_.begin()); |
| chunks_.weak_erase(chunks_.begin()); |
| DCHECK_EQ(chunk->header.size(), kHeaderLength); |
| DCHECK_EQ(chunk->content->size(), chunk->ExpectedContentLength()); |
| total_bytes_stored_ -= chunk->content->size(); |
| total_bytes_stored_ -= kHeaderLength; |
| return chunk->content.Pass(); |
| } |
| |
| void ChunkedByteBuffer::Clear() { |
| chunks_.clear(); |
| partial_chunk_.reset(new Chunk()); |
| total_bytes_stored_ = 0; |
| } |
| |
| ChunkedByteBuffer::Chunk::Chunk() : content(new std::vector<uint8_t>()) {} |
| |
| ChunkedByteBuffer::Chunk::~Chunk() { |
| } |
| |
| size_t ChunkedByteBuffer::Chunk::ExpectedContentLength() const { |
| DCHECK_EQ(header.size(), kHeaderLength); |
| return static_cast<size_t>(ReadBigEndian32(&header[0])); |
| } |
| |
| } // namespace speech |
| } // namespace cobalt |