glibmm  2.76.0
Public Types | Public Member Functions | Static Public Member Functions | Protected Attributes | Related Functions | List of all members
Glib::Checksum Class Reference

Computes the checksum for data. More...

#include <glibmm/checksum.h>

Public Types

enum class  Type {
  MD5 ,
  SHA1 ,
  SHA256 ,
  SHA512 ,
  SHA384
}
 The hashing algorithm to be used by Checksum when performing the digest of some data. More...
 

Public Member Functions

 Checksum ()
 
 Checksum (GChecksum * gobject, bool make_a_copy=true)
 
 Checksum (const Checksum & other)
 
Checksumoperator= (const Checksum & other)
 
 Checksum (Checksum && other) noexcept
 
Checksumoperator= (Checksum && other) noexcept
 
 ~Checksum () noexcept
 
void swap (Checksum & other) noexcept
 
GChecksum * gobj ()
 Provides access to the underlying C instance. More...
 
const GChecksum * gobj () const
 Provides access to the underlying C instance. More...
 
GChecksum * gobj_copy () const
 Provides access to the underlying C instance. The caller is responsible for freeing it. Use when directly setting fields in structs. More...
 
 Checksum (Type checksum_type)
 Creates a new Checksum, using the checksum algorithm checksum_type. More...
 
 operator bool () const
 Returns true if the Checksum object is valid. More...
 
void reset ()
 Resets the state of the checksum back to its initial state. More...
 
void update (const guchar *data, gssize length)
 Feeds data into an existing Checksum. More...
 
void update (const std::string &data)
 Feeds data into an existing Checksum. More...
 
void get_digest (guint8 * buffer, gsize * digest_len) const
 Gets the digest from checksum as a raw binary vector and places it into buffer. More...
 
std::string get_string () const
 Gets the digest as a hexadecimal string. More...
 

Static Public Member Functions

static GType get_type ()
 Get the GType for this class, for use with the underlying GObject type system. More...
 
static std::string compute_checksum (Type checksum_type, const guchar *data, gsize length)
 Computes the checksum for a binary data of length. More...
 
static std::string compute_checksum (Type checksum_type, const std::string & str)
 Computes the checksum of a string. More...
 
static gssize get_length (Type checksum_type)
 Gets the length in bytes of digests of type checksum_type. More...
 

Protected Attributes

GChecksum * gobject_
 

Related Functions

(Note that these are not member functions.)

void swap (Checksum & lhs, Checksum & rhs) noexcept
 
Glib::Checksum wrap (GChecksum * object, bool take_copy=false)
 A Glib::wrap() method for this object. More...
 

Detailed Description

Computes the checksum for data.

This is a generic API for computing checksums (or "digests") for a sequence of arbitrary bytes, using various hashing algorithms like MD5, SHA-1 and SHA-256. Checksums are commonly used in various environments and specifications.

glibmm supports incremental checksums by calling update() as long as there's data available and then using get_string() or get_digest() to compute the checksum and return it either as a string in hexadecimal form, or as a raw sequence of bytes. To compute the checksum for binary blobs and NULL-terminated strings in one go, use the static compute_checksum() convenience functions().

Since glibmm 2.16:

Constructor & Destructor Documentation

◆ Checksum() [1/5]

Glib::Checksum::Checksum ( )

◆ Checksum() [2/5]

Glib::Checksum::Checksum ( GChecksum *  gobject,
bool  make_a_copy = true 
)
explicit

◆ Checksum() [3/5]

Glib::Checksum::Checksum ( const Checksum other)

◆ Checksum() [4/5]

Glib::Checksum::Checksum ( Checksum &&  other)
noexcept

◆ ~Checksum()

Glib::Checksum::~Checksum ( )
noexcept

◆ Checksum() [5/5]

Glib::Checksum::Checksum ( Type  checksum_type)
explicit

Creates a new Checksum, using the checksum algorithm checksum_type.

If the checksum_type is not known, then operator bool() will return false.

Parameters
checksum_typeChecksum type, one of defined above.

Member Function Documentation

◆ compute_checksum() [1/2]

static std::string Glib::Checksum::compute_checksum ( Type  checksum_type,
const guchar *  data,
gsize  length 
)
static

Computes the checksum for a binary data of length.

This is a convenience wrapper for g_checksum_new(), g_checksum_get_string() and g_checksum_free().

The hexadecimal string returned will be in lower case.

Since glibmm 2.16:
Parameters
checksum_typeA Glib::Checksum::Type.
dataBinary blob to compute the digest of.
lengthLength of data.
Returns
The digest of the binary data as a string in hexadecimal, or nullptr if g_checksum_new() fails for checksum_type.

◆ compute_checksum() [2/2]

static std::string Glib::Checksum::compute_checksum ( Type  checksum_type,
const std::string str 
)
static

Computes the checksum of a string.

Parameters
checksum_typeA Type
strThe string to compute the checksum of.
Returns
The checksum as a hexadecimal string.

◆ get_digest()

void Glib::Checksum::get_digest ( guint8 *  buffer,
gsize *  digest_len 
) const

Gets the digest from checksum as a raw binary vector and places it into buffer.

The size of the digest depends on the type of checksum.

Once this function has been called, the Checksum is closed and can no longer be updated with g_checksum_update().

Since glibmm 2.16:
Parameters
bufferOutput buffer.
digest_lenAn inout parameter. The caller initializes it to the size of buffer. After the call it contains the length of the digest.

◆ get_length()

static gssize Glib::Checksum::get_length ( Type  checksum_type)
static

Gets the length in bytes of digests of type checksum_type.

Parameters
checksum_typeA Type.
Returns
The checksum length, or -1 if checksum_type is not supported.

◆ get_string()

std::string Glib::Checksum::get_string ( ) const

Gets the digest as a hexadecimal string.

Once this function has been called the Checksum can no longer be updated with g_checksum_update().

The hexadecimal characters will be lower case.

Since glibmm 2.16:
Returns
The hexadecimal representation of the checksum. The returned string is owned by the checksum and should not be modified or freed.

◆ get_type()

static GType Glib::Checksum::get_type ( )
static

Get the GType for this class, for use with the underlying GObject type system.

◆ gobj() [1/2]

GChecksum* Glib::Checksum::gobj ( )
inline

Provides access to the underlying C instance.

◆ gobj() [2/2]

const GChecksum* Glib::Checksum::gobj ( ) const
inline

Provides access to the underlying C instance.

◆ gobj_copy()

GChecksum* Glib::Checksum::gobj_copy ( ) const

Provides access to the underlying C instance. The caller is responsible for freeing it. Use when directly setting fields in structs.

◆ operator bool()

Glib::Checksum::operator bool ( ) const
explicit

Returns true if the Checksum object is valid.

This will return false, for instance, if an unsupported checksum type was provided to the constructor.

◆ operator=() [1/2]

Checksum& Glib::Checksum::operator= ( Checksum &&  other)
noexcept

◆ operator=() [2/2]

Checksum& Glib::Checksum::operator= ( const Checksum other)

◆ reset()

void Glib::Checksum::reset ( )

Resets the state of the checksum back to its initial state.

Since glibmm 2.18:

◆ swap()

void Glib::Checksum::swap ( Checksum other)
noexcept

◆ update() [1/2]

void Glib::Checksum::update ( const guchar *  data,
gssize  length 
)

Feeds data into an existing Checksum.

The checksum must still be open, that is g_checksum_get_string() or g_checksum_get_digest() must not have been called on checksum.

Since glibmm 2.16:
Parameters
dataBuffer used to compute the checksum.
lengthSize of the buffer, or -1 if it is a null-terminated string.

◆ update() [2/2]

void Glib::Checksum::update ( const std::string data)

Feeds data into an existing Checksum.

The checksum must still be open, that is get_string() or get_digest() must not have been called on the checksum.

Parameters
dataBuffer used to compute the checksum

Friends And Related Function Documentation

◆ swap()

void swap ( Checksum lhs,
Checksum rhs 
)
related
Parameters
lhsThe left-hand side
rhsThe right-hand side

◆ wrap()

Glib::Checksum wrap ( GChecksum *  object,
bool  take_copy = false 
)
related

A Glib::wrap() method for this object.

Parameters
objectThe C instance.
take_copyFalse if the result should take ownership of the C instance. True if it should take a new copy or ref.
Returns
A C++ instance that wraps this C instance.

Member Data Documentation

◆ gobject_

GChecksum* Glib::Checksum::gobject_
protected