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Diffstat (limited to 'include/lldb/Utility/DataEncoder.h')
| -rw-r--r-- | include/lldb/Utility/DataEncoder.h | 402 |
1 files changed, 402 insertions, 0 deletions
diff --git a/include/lldb/Utility/DataEncoder.h b/include/lldb/Utility/DataEncoder.h new file mode 100644 index 000000000000..ea347d86237b --- /dev/null +++ b/include/lldb/Utility/DataEncoder.h @@ -0,0 +1,402 @@ +//===-- DataEncoder.h -------------------------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef liblldb_DataEncoder_h_ +#define liblldb_DataEncoder_h_ + +#if defined(__cplusplus) + +#include "lldb/lldb-defines.h" // for DISALLOW_COPY_AND_ASSIGN +#include "lldb/lldb-enumerations.h" // for ByteOrder +#include "lldb/lldb-forward.h" // for DataBufferSP +#include "lldb/lldb-types.h" // for addr_t + +#include <stddef.h> // for size_t +#include <stdint.h> + +namespace lldb_private { + +//---------------------------------------------------------------------- +/// @class DataEncoder DataEncoder.h "lldb/Core/DataEncoder.h" +/// @brief An binary data encoding class. +/// +/// DataEncoder is a class that can encode binary data (swapping if needed) +/// to a data buffer. The data buffer can be caller owned, or can be +/// shared data that can be shared between multiple DataEncoder or +/// DataEncoder instances. +/// +/// @see DataBuffer +//---------------------------------------------------------------------- +class DataEncoder { +public: + //------------------------------------------------------------------ + /// Default constructor. + /// + /// Initialize all members to a default empty state. + //------------------------------------------------------------------ + DataEncoder(); + + //------------------------------------------------------------------ + /// Construct with a buffer that is owned by the caller. + /// + /// This constructor allows us to use data that is owned by the + /// caller. The data must stay around as long as this object is + /// valid. + /// + /// @param[in] data + /// A pointer to caller owned data. + /// + /// @param[in] data_length + /// The length in bytes of \a data. + /// + /// @param[in] byte_order + /// A byte order of the data that we are extracting from. + /// + /// @param[in] addr_size + /// A new address byte size value. + //------------------------------------------------------------------ + DataEncoder(void *data, uint32_t data_length, lldb::ByteOrder byte_order, + uint8_t addr_size); + + //------------------------------------------------------------------ + /// Construct with shared data. + /// + /// Copies the data shared pointer which adds a reference to the + /// contained in \a data_sp. The shared data reference is reference + /// counted to ensure the data lives as long as anyone still has a + /// valid shared pointer to the data in \a data_sp. + /// + /// @param[in] data_sp + /// A shared pointer to data. + /// + /// @param[in] byte_order + /// A byte order of the data that we are extracting from. + /// + /// @param[in] addr_size + /// A new address byte size value. + //------------------------------------------------------------------ + DataEncoder(const lldb::DataBufferSP &data_sp, lldb::ByteOrder byte_order, + uint8_t addr_size); + + //------------------------------------------------------------------ + /// Destructor + /// + /// If this object contains a valid shared data reference, the + /// reference count on the data will be decremented, and if zero, + /// the data will be freed. + //------------------------------------------------------------------ + ~DataEncoder(); + + //------------------------------------------------------------------ + /// Clears the object state. + /// + /// Clears the object contents back to a default invalid state, and + /// release any references to shared data that this object may + /// contain. + //------------------------------------------------------------------ + void Clear(); + + //------------------------------------------------------------------ + /// Get the current address size. + /// + /// Return the size in bytes of any address values this object will + /// extract. + /// + /// @return + /// The size in bytes of address values that will be extracted. + //------------------------------------------------------------------ + uint8_t GetAddressByteSize() const { return m_addr_size; } + + //------------------------------------------------------------------ + /// Get the number of bytes contained in this object. + /// + /// @return + /// The total number of bytes of data this object refers to. + //------------------------------------------------------------------ + size_t GetByteSize() const { return m_end - m_start; } + + //------------------------------------------------------------------ + /// Get the data end pointer. + /// + /// @return + /// Returns a pointer to the next byte contained in this + /// object's data, or NULL of there is no data in this object. + //------------------------------------------------------------------ + uint8_t *GetDataEnd() { return m_end; } + + const uint8_t *GetDataEnd() const { return m_end; } + + //------------------------------------------------------------------ + /// Get the shared data offset. + /// + /// Get the offset of the first byte of data in the shared data (if + /// any). + /// + /// @return + /// If this object contains shared data, this function returns + /// the offset in bytes into that shared data, zero otherwise. + //------------------------------------------------------------------ + size_t GetSharedDataOffset() const; + + //------------------------------------------------------------------ + /// Get the current byte order value. + /// + /// @return + /// The current byte order value from this object's internal + /// state. + //------------------------------------------------------------------ + lldb::ByteOrder GetByteOrder() const { return m_byte_order; } + + //------------------------------------------------------------------ + /// Get the data start pointer. + /// + /// @return + /// Returns a pointer to the first byte contained in this + /// object's data, or NULL of there is no data in this object. + //------------------------------------------------------------------ + uint8_t *GetDataStart() { return m_start; } + + const uint8_t *GetDataStart() const { return m_start; } + + //------------------------------------------------------------------ + /// Encode unsigned integer values into the data at \a offset. + /// + /// @param[in] offset + /// The offset within the contained data at which to put the + /// data. + /// + /// @param[in] value + /// The value to encode into the data. + /// + /// @return + /// The next offset in the bytes of this data if the data + /// was successfully encoded, UINT32_MAX if the encoding failed. + //------------------------------------------------------------------ + uint32_t PutU8(uint32_t offset, uint8_t value); + + uint32_t PutU16(uint32_t offset, uint16_t value); + + uint32_t PutU32(uint32_t offset, uint32_t value); + + uint32_t PutU64(uint32_t offset, uint64_t value); + + //------------------------------------------------------------------ + /// Encode an unsigned integer of size \a byte_size to \a offset. + /// + /// Encode a single integer value at \a offset and return the offset + /// that follows the newly encoded integer when the data is successfully + /// encoded into the existing data. There must be enough room in the + /// data, else UINT32_MAX will be returned to indicate that encoding + /// failed. + /// + /// @param[in] offset + /// The offset within the contained data at which to put the + /// encoded integer. + /// + /// @param[in] byte_size + /// The size in byte of the integer to encode. + /// + /// @param[in] value + /// The integer value to write. The least significant bytes of + /// the integer value will be written if the size is less than + /// 8 bytes. + /// + /// @return + /// The next offset in the bytes of this data if the integer + /// was successfully encoded, UINT32_MAX if the encoding failed. + //------------------------------------------------------------------ + uint32_t PutMaxU64(uint32_t offset, uint32_t byte_size, uint64_t value); + + //------------------------------------------------------------------ + /// Encode an arbitrary number of bytes. + /// + /// @param[in] offset + /// The offset in bytes into the contained data at which to + /// start encoding. + /// + /// @param[in] src + /// The buffer that contains the bytes to encode. + /// + /// @param[in] src_len + /// The number of bytes to encode. + /// + /// @return + /// The next valid offset within data if the put operation + /// was successful, else UINT32_MAX to indicate the put failed. + //------------------------------------------------------------------ + uint32_t PutData(uint32_t offset, const void *src, uint32_t src_len); + + //------------------------------------------------------------------ + /// Encode an address in the existing buffer at \a offset bytes into + /// the buffer. + /// + /// Encode a single address (honoring the m_addr_size member) to + /// the data and return the next offset where subsequent data would + /// go. + /// pointed to by \a offset_ptr. The size of the extracted address + /// comes from the \a m_addr_size member variable and should be + /// set correctly prior to extracting any address values. + /// + /// @param[in,out] offset_ptr + /// A pointer to an offset within the data that will be advanced + /// by the appropriate number of bytes if the value is extracted + /// correctly. If the offset is out of bounds or there are not + /// enough bytes to extract this value, the offset will be left + /// unmodified. + /// + /// @return + /// The next valid offset within data if the put operation + /// was successful, else UINT32_MAX to indicate the put failed. + //------------------------------------------------------------------ + uint32_t PutAddress(uint32_t offset, lldb::addr_t addr); + + //------------------------------------------------------------------ + /// Put a C string to \a offset. + /// + /// Encodes a C string into the existing data including the + /// terminating + /// + /// @param[in,out] offset_ptr + /// A pointer to an offset within the data that will be advanced + /// by the appropriate number of bytes if the value is extracted + /// correctly. If the offset is out of bounds or there are not + /// enough bytes to extract this value, the offset will be left + /// unmodified. + /// + /// @return + /// A pointer to the C string value in the data. If the offset + /// pointed to by \a offset_ptr is out of bounds, or if the + /// offset plus the length of the C string is out of bounds, + /// NULL will be returned. + //------------------------------------------------------------------ + uint32_t PutCString(uint32_t offset_ptr, const char *cstr); + + lldb::DataBufferSP &GetSharedDataBuffer() { return m_data_sp; } + + //------------------------------------------------------------------ + /// Set the address byte size. + /// + /// Set the size in bytes that will be used when extracting any + /// address and pointer values from data contained in this object. + /// + /// @param[in] addr_size + /// The size in bytes to use when extracting addresses. + //------------------------------------------------------------------ + void SetAddressByteSize(uint8_t addr_size) { m_addr_size = addr_size; } + + //------------------------------------------------------------------ + /// Set data with a buffer that is caller owned. + /// + /// Use data that is owned by the caller when extracting values. + /// The data must stay around as long as this object, or any object + /// that copies a subset of this object's data, is valid. If \a + /// bytes is NULL, or \a length is zero, this object will contain + /// no data. + /// + /// @param[in] bytes + /// A pointer to caller owned data. + /// + /// @param[in] length + /// The length in bytes of \a bytes. + /// + /// @param[in] byte_order + /// A byte order of the data that we are extracting from. + /// + /// @return + /// The number of bytes that this object now contains. + //------------------------------------------------------------------ + uint32_t SetData(void *bytes, uint32_t length, lldb::ByteOrder byte_order); + + //------------------------------------------------------------------ + /// Adopt a subset of shared data in \a data_sp. + /// + /// Copies the data shared pointer which adds a reference to the + /// contained in \a data_sp. The shared data reference is reference + /// counted to ensure the data lives as long as anyone still has a + /// valid shared pointer to the data in \a data_sp. The byte order + /// and address byte size settings remain the same. If + /// \a offset is not a valid offset in \a data_sp, then no reference + /// to the shared data will be added. If there are not \a length + /// bytes available in \a data starting at \a offset, the length + /// will be truncated to contains as many bytes as possible. + /// + /// @param[in] data_sp + /// A shared pointer to data. + /// + /// @param[in] offset + /// The offset into \a data_sp at which the subset starts. + /// + /// @param[in] length + /// The length in bytes of the subset of \a data_sp. + /// + /// @return + /// The number of bytes that this object now contains. + //------------------------------------------------------------------ + uint32_t SetData(const lldb::DataBufferSP &data_sp, uint32_t offset = 0, + uint32_t length = UINT32_MAX); + + //------------------------------------------------------------------ + /// Set the byte_order value. + /// + /// Sets the byte order of the data to extract. Extracted values + /// will be swapped if necessary when decoding. + /// + /// @param[in] byte_order + /// The byte order value to use when extracting data. + //------------------------------------------------------------------ + void SetByteOrder(lldb::ByteOrder byte_order) { m_byte_order = byte_order; } + + //------------------------------------------------------------------ + /// Test the validity of \a offset. + /// + /// @return + /// \b true if \a offset is a valid offset into the data in this + /// object, \b false otherwise. + //------------------------------------------------------------------ + bool ValidOffset(uint32_t offset) const { return offset < GetByteSize(); } + + //------------------------------------------------------------------ + /// Test the availability of \a length bytes of data from \a offset. + /// + /// @return + /// \b true if \a offset is a valid offset and there are \a + /// length bytes available at that offset, \b false otherwise. + //------------------------------------------------------------------ + bool ValidOffsetForDataOfSize(uint32_t offset, uint32_t length) const { + return length <= BytesLeft(offset); + } + + uint32_t BytesLeft(uint32_t offset) const { + const uint32_t size = GetByteSize(); + if (size > offset) + return size - offset; + return 0; + } + +protected: + //------------------------------------------------------------------ + // Member variables + //------------------------------------------------------------------ + uint8_t *m_start; ///< A pointer to the first byte of data. + uint8_t *m_end; ///< A pointer to the byte that is past the end of the data. + lldb::ByteOrder + m_byte_order; ///< The byte order of the data we are extracting from. + uint8_t m_addr_size; ///< The address size to use when extracting pointers or + /// addresses + mutable lldb::DataBufferSP m_data_sp; ///< The shared pointer to data that can + /// be shared among multiple instances + +private: + DISALLOW_COPY_AND_ASSIGN(DataEncoder); +}; + +} // namespace lldb_private + +#endif // #if defined (__cplusplus) +#endif // #ifndef liblldb_DataEncoder_h_ |