Byte array with an `_io` member: C++11/STL parsing library

Helper type to work around Kaitai Struct not providing an _io member for plain byte arrays.

KS implementation details

License: MIT

This page hosts a formal specification of Byte array with an `_io` member using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for C++11/STL generated by Kaitai Struct depends on the C++/STL runtime library. You have to install it before you can parse data.

For C++, the easiest way is to clone the runtime library sources and build them along with your project.

Code

Using Kaitai Struct in C++/STL usually consists of 3 steps.

  1. We need to create an STL input stream (std::istream). One can open local file for that, or use existing std::string or char* buffer.
    #include <fstream>
    
    std::ifstream is("path/to/local/file.bytes_with_io", std::ifstream::binary);
    
    #include <sstream>
    
    std::istringstream is(str);
    
    #include <sstream>
    
    const char buf[] = { ... };
    std::string str(buf, sizeof buf);
    std::istringstream is(str);
    
  2. We need to wrap our input stream into Kaitai stream:
    #include "kaitai/kaitaistream.h"
    
    kaitai::kstream ks(&is);
    
  3. And finally, we can invoke the parsing:
    bytes_with_io_t data(&ks);
    

After that, one can get various attributes from the structure by invoking getter methods like:

data.data() // => The actual data.

C++11/STL source code to parse Byte array with an `_io` member

bytes_with_io.h

#pragma once

// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

#include "kaitai/kaitaistruct.h"
#include <stdint.h>
#include <memory>

#if KAITAI_STRUCT_VERSION < 9000L
#error "Incompatible Kaitai Struct C++/STL API: version 0.9 or later is required"
#endif

/**
 * Helper type to work around Kaitai Struct not providing an `_io` member for plain byte arrays.
 */

class bytes_with_io_t : public kaitai::kstruct {

public:

    bytes_with_io_t(kaitai::kstream* p__io, kaitai::kstruct* p__parent = nullptr, bytes_with_io_t* p__root = nullptr);

private:
    void _read();
    void _clean_up();

public:
    ~bytes_with_io_t();

private:
    std::string m_data;
    bytes_with_io_t* m__root;
    kaitai::kstruct* m__parent;

public:

    /**
     * The actual data.
     */
    std::string data() const { return m_data; }
    bytes_with_io_t* _root() const { return m__root; }
    kaitai::kstruct* _parent() const { return m__parent; }
};

bytes_with_io.cpp

// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

#include "bytes_with_io.h"

bytes_with_io_t::bytes_with_io_t(kaitai::kstream* p__io, kaitai::kstruct* p__parent, bytes_with_io_t* p__root) : kaitai::kstruct(p__io) {
    m__parent = p__parent;
    m__root = this;
    _read();
}

void bytes_with_io_t::_read() {
    m_data = m__io->read_bytes_full();
}

bytes_with_io_t::~bytes_with_io_t() {
    _clean_up();
}

void bytes_with_io_t::_clean_up() {
}