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Binary Native Endian
Description

Binary native endian parsers are designed to parse binary byte streams that are laid out in the native endianness of the target architecture.

Header
// forwards to <boost/spirit/home/qi/binary.hpp>
#include <boost/spirit/include/qi_binary.hpp>

Also, see Include Structure.

Namespace

Name

boost::spirit::byte_ // alias: boost::spirit::qi::byte_

boost::spirit::word // alias: boost::spirit::qi::word

boost::spirit::dword // alias: boost::spirit::qi::dword

boost::spirit::qword // alias: boost::spirit::qi::qword

[Note] Note

qword is only available on platforms where the preprocessor constant BOOST_HAS_LONG_LONG is defined (i.e. on platforms having native support for unsigned long long (64 bit) integer types).

Model of

PrimitiveParser

Notation

b

A single byte (8 bit binary value) or a Lazy Argument that evaluates to a single byte. This value is always in native endian.

w

A 16 bit binary value or a Lazy Argument that evaluates to a 16 bit binary value. This value is always in native endian.

dw

A 32 bit binary value or a Lazy Argument that evaluates to a 32 bit binary value. This value is always in native endian.

qw

A 64 bit binary value or a Lazy Argument that evaluates to a 64 bit binary value. This value is always in native endian.

Expression Semantics

Semantics of an expression is defined only where it differs from, or is not defined in PrimitiveParser.

Expression

Description

byte_

Matches any 8 bit native endian binary.

word

Matches any 16 bit native endian binary.

dword

Matches any 32 bit native endian binary.

qword

Matches any 64 bit native endian binary.

byte_(b)

Matches an exact 8 bit native endian binary.

word(w)

Matches an exact 16 bit native endian binary.

dword(dw)

Matches an exact 32 bit native endian binary.

qword(qw)

Matches an exact 64 bit native endian binary.

Attributes

Expression

Attribute

byte_

boost::uint_least8_t

word

boost::uint_least16_t

dword

boost::uint_least32_t

qword

boost::uint_least64_t

byte_(b)

unused

word(w)

unused

dword(dw)

unused

qword(qw)

unused

Complexity

O(N), where N is the number of bytes parsed

Example
[Note] Note

The test harness for the example(s) below is presented in the Basics Examples section.

Using declarations and variables:

using boost::spirit::qi::byte_;
using boost::spirit::qi::word;
using boost::spirit::qi::dword;
using boost::spirit::qi::qword;

boost::uint8_t uc;
boost::uint16_t us;
boost::uint32_t ui;
boost::uint64_t ul;

Basic usage of the native binary parsers for little endian platforms:

test_parser_attr("\x01", byte_, uc); assert(uc == 0x01);
test_parser_attr("\x01\x02", word, us); assert(us == 0x0201);
test_parser_attr("\x01\x02\x03\x04", dword, ui); assert(ui == 0x04030201);
test_parser_attr("\x01\x02\x03\x04\x05\x06\x07\x08", qword, ul);
assert(ul == 0x0807060504030201LL);

test_parser("\x01", byte_(0x01));
test_parser("\x01\x02", word(0x0201));
test_parser("\x01\x02\x03\x04", dword(0x04030201));
test_parser("\x01\x02\x03\x04\x05\x06\x07\x08",
    qword(0x0807060504030201LL));

Basic usage of the native binary parsers for big endian platforms:

test_parser_attr("\x01", byte_, uc); assert(uc == 0x01);
test_parser_attr("\x01\x02", word, us); assert(us ==  0x0102);
test_parser_attr("\x01\x02\x03\x04", dword, ui); assert(ui == 0x01020304);
test_parser_attr("\x01\x02\x03\x04\x05\x06\x07\x08", qword, ul);
assert(0x0102030405060708LL);

test_parser("\x01", byte_(0x01));
test_parser("\x01\x02", word(0x0102));
test_parser("\x01\x02\x03\x04", dword(0x01020304));
test_parser("\x01\x02\x03\x04\x05\x06\x07\x08",
    qword(0x0102030405060708LL));


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