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Binary Big Endianness Parsers
Description

Binary big endian parsers are designed to parse binary byte streams that are laid out in big endian.

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

Also, see Include Structure.

Namespace

Name

boost::spirit::big_word // alias: boost::spirit::qi::big_word

boost::spirit::big_dword // alias: boost::spirit::qi::big_dword

boost::spirit::big_qword // alias: boost::spirit::qi::big_qword

[Note] Note

big_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

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

big_word

Matches any 16 bit big endian binary.

big_dword

Matches any 32 bit big endian binary.

big_qword

Matches any 64 bit big endian binary.

big_word(w)

Matches an exact 16 bit big endian binary.

big_dword(dw)

Matches an exact 32 bit big endian binary.

big_qword(qw)

Matches an exact 32 bit big endian binary.

Attributes

Expression

Attribute

big_word

boost::uint_least16_t

big_dword

boost::uint_least32_t

big_qword

boost::uint_least64_t

big_word(w)

unused

big_dword(dw)

unused

big_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::big_word;
using boost::spirit::qi::big_dword;
using boost::spirit::qi::big_qword;

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

Basic usage of the big endian binary parsers:

test_parser_attr("\x01\x02", big_word, us); assert(us ==  0x0102);
test_parser_attr("\x01\x02\x03\x04", big_dword, ui); assert(ui == 0x01020304);
test_parser_attr("\x01\x02\x03\x04\x05\x06\x07\x08", big_qword, ul);
assert(0x0102030405060708LL);

test_parser("\x01\x02", big_word(0x0102));
test_parser("\x01\x02\x03\x04", big_dword(0x01020304));
test_parser("\x01\x02\x03\x04\x05\x06\x07\x08",
    big_qword(0x0102030405060708LL));


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