//===-- 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-private.h" #include <limits.h> #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 a 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 significate 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[int] src /// The buffer that contains the 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 (const 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; 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 multilple instances private: DISALLOW_COPY_AND_ASSIGN (DataEncoder); }; } // namespace lldb_private #endif // #if defined (__cplusplus) #endif // #ifndef liblldb_DataEncoder_h_