pqxx::binarystring Class Reference

Binary data corresponding to PostgreSQL's "BYTEA" binary-string type. More...

#include <binarystring.hxx>

Public Types
using	char_type = unsigned char
using	value_type = char_type
using	size_type = std::size_t
using	difference_type = long
using	const_reference = value_type const &
using	const_pointer = value_type const *
using	const_iterator = const_pointer
using	const_reverse_iterator = std::reverse_iterator< const_iterator >

Public Member Functions
	binarystring (binarystring const &)=default
	binarystring (field const &)
	Read and unescape bytea field. More...
	binarystring (std::string_view)
	Copy binary data from std::string_view on binary data. More...
	binarystring (void const *, std::size_t)
	Copy binary data of given length straight out of memory. More...
	binarystring (std::shared_ptr< value_type > ptr, size_type size)
	Efficiently wrap a buffer of binary data in a binarystring. More...
size_type	size () const noexcept
	Size of converted string in bytes. More...
size_type	length () const noexcept
	Size of converted string in bytes. More...
bool	empty () const noexcept
const_iterator	begin () const noexcept
const_iterator	cbegin () const noexcept
const_iterator	end () const noexcept
const_iterator	cend () const noexcept
const_reference	front () const noexcept
const_reference	back () const noexcept
const_reverse_iterator	rbegin () const
const_reverse_iterator	crbegin () const
const_reverse_iterator	rend () const
const_reverse_iterator	crend () const
value_type const *	data () const noexcept
	Unescaped field contents. More...
const_reference	operator[] (size_type i) const noexcept
PQXX_PURE bool	operator== (binarystring const &) const noexcept
bool	operator!= (binarystring const &rhs) const noexcept
binarystring &	operator= (binarystring const &)
const_reference	at (size_type) const
	Index contained string, checking for valid index. More...
void	swap (binarystring &)
	Swap contents with other binarystring. More...
char const *	get () const noexcept
	Raw character buffer (no terminating zero is added). More...
std::string_view	view () const noexcept
	Read contents as a std::string_view. More...
std::string	str () const
	Read as regular C++ string (may include null characters). More...
std::byte const *	bytes () const
	Access data as a pointer to std::byte. More...
pqxx::bytes_view	bytes_view () const
	Read data as a bytes_view. More...

Detailed Description

Binary data corresponding to PostgreSQL's "BYTEA" binary-string type.

Deprecated:

Use bytes and bytes_view for binary data. In C++20 or better, any contiguous_range of std::byte will do.

This class represents a binary string as stored in a field of type bytea.

Internally a binarystring is zero-terminated, but it may also contain null bytes, they're just like any other byte value. So don't assume that it's safe to treat the contents as a C-style string.

The binarystring retains its value even if the result it was obtained from is destroyed, but it cannot be copied or assigned.

To include a binarystring value in an SQL query, escape and quote it using the transaction's quote_raw function.

Warning

This class is implemented as a reference-counting smart pointer. Copying, swapping, and destroying binarystring objects that refer to the same underlying data block is not thread-safe. If you wish to pass binarystrings around between threads, make sure that each of these operations is protected against concurrency with similar operations on the same object, or other objects pointing to the same data block.

Member Typedef Documentation

char_type

using pqxx::binarystring::char_type = unsigned char

const_iterator

using pqxx::binarystring::const_iterator = const_pointer

const_pointer

using pqxx::binarystring::const_pointer = value_type const *

const_reference

using pqxx::binarystring::const_reference = value_type const &

const_reverse_iterator

using pqxx::binarystring::const_reverse_iterator = std::reverse_iterator<const_iterator>

difference_type

using pqxx::binarystring::difference_type = long

size_type

using pqxx::binarystring::size_type = std::size_t

value_type

using pqxx::binarystring::value_type = char_type

Constructor & Destructor Documentation

binarystring() [1/5]

pqxx::binarystring::binarystring ( binarystring const &  )

default

binarystring() [2/5]

PQXX_COLD pqxx::binarystring::binarystring ( field const &  F )

explicit

Read and unescape bytea field.

The field will be zero-terminated, even if the original bytea field isn't.

Parameters

F	the field to read; must be a bytea field

References pqxx::field::c_str(), data(), and pqxx::internal::pq::pqfreemem().

binarystring() [3/5]

pqxx::binarystring::binarystring ( std::string_view  s )

explicit

Copy binary data from std::string_view on binary data.

This is inefficient in that it copies the data to a buffer allocated on the heap.

binarystring() [4/5]

pqxx::binarystring::binarystring	(	void const *	binary_data,
		std::size_t	len
	)

Copy binary data of given length straight out of memory.

binarystring() [5/5]

pqxx::binarystring::binarystring	(	std::shared_ptr< value_type >	ptr,
		size_type	size
	)

Efficiently wrap a buffer of binary data in a binarystring.

Member Function Documentation

at()

PQXX_COLD pqxx::binarystring::const_reference pqxx::binarystring::at

(

size_type

n

)

const

Index contained string, checking for valid index.

References pqxx::to_string().

back()

const_reference pqxx::binarystring::back ( ) const

noexcept

begin()

const_iterator pqxx::binarystring::begin ( ) const

noexcept

bytes()

std::byte const* pqxx::binarystring::bytes

(

)

const

Access data as a pointer to std::byte.

bytes_view()

pqxx::bytes_view pqxx::binarystring::bytes_view

(

)

const

Read data as a bytes_view.

Referenced by pqxx::connection::quote(), and pqxx::transaction_base::quote().

cbegin()

const_iterator pqxx::binarystring::cbegin ( ) const

noexcept

cend()

const_iterator pqxx::binarystring::cend ( ) const

noexcept

crbegin()

const_reverse_iterator pqxx::binarystring::crbegin

(

)

const

crend()

const_reverse_iterator pqxx::binarystring::crend

(

)

const

data()

value_type const* pqxx::binarystring::data ( ) const

noexcept

Unescaped field contents.

Referenced by binarystring().

empty()

bool pqxx::binarystring::empty ( ) const

noexcept

end()

const_iterator pqxx::binarystring::end ( ) const

noexcept

front()

const_reference pqxx::binarystring::front ( ) const

noexcept

get()

char const* pqxx::binarystring::get ( ) const

noexcept

Raw character buffer (no terminating zero is added).

Warning

No terminating zero is added! If the binary data did not end in a null character, you will not find one here.

length()

size_type pqxx::binarystring::length ( ) const

noexcept

Size of converted string in bytes.

operator!=()

bool pqxx::binarystring::operator!= ( binarystring const &  rhs ) const

noexcept

operator=()

pqxx::binarystring & pqxx::binarystring::operator= ( binarystring const &  )

default

operator==()

bool pqxx::binarystring::operator== ( binarystring const &  rhs ) const

noexcept

operator[]()

const_reference pqxx::binarystring::operator[] ( size_type  i ) const

noexcept

rbegin()

const_reverse_iterator pqxx::binarystring::rbegin

(

)

const

rend()

const_reverse_iterator pqxx::binarystring::rend

(

)

const

size()

size_type pqxx::binarystring::size ( ) const

noexcept

Size of converted string in bytes.

str()

std::string pqxx::binarystring::str

(

)

const

Read as regular C++ string (may include null characters).

This creates and returns a new string object. Don't call this repeatedly; retrieve your string once and keep it in a local variable. Also, do not expect to be able to compare the string's address to that of an earlier invocation.

swap()

PQXX_COLD void pqxx::binarystring::swap

(

binarystring &

rhs

)

Swap contents with other binarystring.

view()

std::string_view pqxx::binarystring::view ( ) const

noexcept

Read contents as a std::string_view.

Referenced by pqxx::string_traits< binarystring >::into_buf().

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The documentation for this class was generated from the following files:

• binarystring.hxx
• binarystring.cxx