Pirama Arumuga Nainar | d285ad0 | 2022-02-08 09:26:56 -0800 | [diff] [blame] | 1 | //===-- DataBufferHeap.h ----------------------------------------*- C++ -*-===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #ifndef LLDB_UTILITY_DATABUFFERHEAP_H |
| 10 | #define LLDB_UTILITY_DATABUFFERHEAP_H |
| 11 | |
| 12 | #include "lldb/Utility/DataBuffer.h" |
| 13 | #include "lldb/lldb-types.h" |
| 14 | #include "llvm/ADT/StringRef.h" |
| 15 | |
| 16 | #include <cstdint> |
| 17 | #include <vector> |
| 18 | |
| 19 | namespace lldb_private { |
| 20 | |
| 21 | /// \class DataBufferHeap DataBufferHeap.h "lldb/Core/DataBufferHeap.h" |
| 22 | /// A subclass of DataBuffer that stores a data buffer on the heap. |
| 23 | /// |
| 24 | /// This class keeps its data in a heap based buffer that is owned by the |
| 25 | /// object. This class is best used to store chunks of data that are created |
| 26 | /// or read from sources that can't intelligently and lazily fault new data |
| 27 | /// pages in. Large amounts of data that comes from files should probably use |
| 28 | /// DataBufferLLVM, which can intelligently determine when memory mapping is |
| 29 | /// optimal. |
| 30 | class DataBufferHeap : public DataBuffer { |
| 31 | public: |
| 32 | /// Default constructor |
| 33 | /// |
| 34 | /// Initializes the heap based buffer with no bytes. |
| 35 | DataBufferHeap(); |
| 36 | |
| 37 | /// Construct with size \a n and fill with \a ch. |
| 38 | /// |
| 39 | /// Initialize this class with \a n bytes and fills the buffer with \a ch. |
| 40 | /// |
| 41 | /// \param[in] n |
| 42 | /// The number of bytes that heap based buffer should contain. |
| 43 | /// |
| 44 | /// \param[in] ch |
| 45 | /// The character to use when filling the buffer initially. |
| 46 | DataBufferHeap(lldb::offset_t n, uint8_t ch); |
| 47 | |
| 48 | /// Construct by making a copy of \a src_len bytes from \a src. |
| 49 | /// |
| 50 | /// \param[in] src |
| 51 | /// A pointer to the data to copy. |
| 52 | /// |
| 53 | /// \param[in] src_len |
| 54 | /// The number of bytes in \a src to copy. |
| 55 | DataBufferHeap(const void *src, lldb::offset_t src_len); |
| 56 | |
| 57 | /// Destructor. |
| 58 | /// |
| 59 | /// Virtual destructor since this class inherits from a pure virtual base |
| 60 | /// class #DataBuffer. |
| 61 | ~DataBufferHeap() override; |
| 62 | |
| 63 | /// \copydoc DataBuffer::GetBytes() |
| 64 | uint8_t *GetBytes() override; |
| 65 | |
| 66 | /// \copydoc DataBuffer::GetBytes() const |
| 67 | const uint8_t *GetBytes() const override; |
| 68 | |
| 69 | /// \copydoc DataBuffer::GetByteSize() const |
| 70 | lldb::offset_t GetByteSize() const override; |
| 71 | |
| 72 | /// Set the number of bytes in the data buffer. |
| 73 | /// |
| 74 | /// Sets the number of bytes that this object should be able to contain. |
| 75 | /// This can be used prior to copying data into the buffer. Note that this |
| 76 | /// zero-initializes up to \p byte_size bytes. |
| 77 | /// |
| 78 | /// \param[in] byte_size |
| 79 | /// The new size in bytes that this data buffer should attempt |
| 80 | /// to resize itself to. |
| 81 | /// |
| 82 | /// \return |
| 83 | /// The size in bytes after that this heap buffer was |
| 84 | /// successfully resized to. |
| 85 | lldb::offset_t SetByteSize(lldb::offset_t byte_size); |
| 86 | |
| 87 | /// Makes a copy of the \a src_len bytes in \a src. |
| 88 | /// |
| 89 | /// Copies the data in \a src into an internal buffer. |
| 90 | /// |
| 91 | /// \param[in] src |
| 92 | /// A pointer to the data to copy. |
| 93 | /// |
| 94 | /// \param[in] src_len |
| 95 | /// The number of bytes in \a src to copy. |
| 96 | void CopyData(const void *src, lldb::offset_t src_len); |
| 97 | void CopyData(llvm::StringRef src) { CopyData(src.data(), src.size()); } |
| 98 | |
| 99 | void AppendData(const void *src, uint64_t src_len); |
| 100 | |
| 101 | void Clear(); |
| 102 | |
| 103 | private: |
| 104 | // This object uses a std::vector<uint8_t> to store its data. This takes care |
| 105 | // of free the data when the object is deleted. |
| 106 | typedef std::vector<uint8_t> buffer_t; ///< Buffer type |
| 107 | buffer_t m_data; ///< The heap based buffer where data is stored |
| 108 | }; |
| 109 | |
| 110 | } // namespace lldb_private |
| 111 | |
| 112 | #endif // LLDB_UTILITY_DATABUFFERHEAP_H |