| // Copyright 2018 The PDFium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef CORE_FXCODEC_CFX_CODEC_MEMORY_H_ |
| #define CORE_FXCODEC_CFX_CODEC_MEMORY_H_ |
| |
| #include <memory> |
| |
| #include "core/fxcrt/compiler_specific.h" |
| #include "core/fxcrt/fx_memory_wrappers.h" |
| #include "core/fxcrt/retain_ptr.h" |
| #include "core/fxcrt/span.h" |
| |
| class CFX_CodecMemory final : public Retainable { |
| public: |
| CONSTRUCT_VIA_MAKE_RETAIN; |
| |
| // Returns a span over the unconsumed contents of the buffer. |
| pdfium::span<uint8_t> GetUnconsumedSpan() { |
| return GetBufferSpan().subspan(pos_); |
| } |
| |
| // SAFETY: `size_` must track `buffer_` allocations. |
| pdfium::span<uint8_t> GetBufferSpan() { |
| return UNSAFE_BUFFERS(pdfium::make_span(buffer_.get(), size_)); |
| } |
| size_t GetSize() const { return size_; } |
| size_t GetPosition() const { return pos_; } |
| bool IsEOF() const { return pos_ >= size_; } |
| size_t ReadBlock(pdfium::span<uint8_t> buffer); |
| |
| // Sets the cursor position to |pos| if possible. |
| bool Seek(size_t pos); |
| |
| // Try to change the size of the buffer, keep the old one on failure. |
| bool TryResize(size_t new_buffer_size); |
| |
| // Schlep the bytes down the buffer. |
| void Consume(size_t consumed); |
| |
| private: |
| explicit CFX_CodecMemory(size_t buffer_size); |
| ~CFX_CodecMemory() override; |
| |
| // TODO(tsepez): convert to a fixed array type. |
| std::unique_ptr<uint8_t, FxFreeDeleter> buffer_; |
| size_t size_ = 0; |
| size_t pos_ = 0; |
| }; |
| |
| #endif // CORE_FXCODEC_CFX_CODEC_MEMORY_H_ |