agentxcpp::oid Class Reference

Represents an SNMP object identifier (OID). More...

#include <oid.hpp>

Inheritance diagram for agentxcpp::oid:

Collaboration diagram for agentxcpp::oid:

List of all members.

Public Member Functions
	oid ()
	Default Constructor.
	oid (std::string id)
	Initialize an oid object with an OID in string format.
	oid (const oid &o, std::string id)
	Initialize an oid object with another oid plus an OID in string format.
oid &	operator= (const oid &o)
	Assignment operator.
bool	get_include ()
	Get the current include value.
void	set_include (bool i)
	set the include value
data_t	serialize () const
	Encode an OID object as described in RFC 2741, section 5.1.
	oid (data_t::const_iterator &pos, const data_t::const_iterator &end, bool big_endian=true)
	Construct the object from input stream.
bool	operator< (const oid &o) const
	The less-than operator.
bool	operator== (const oid &o) const
	The equal-operator.
bool	operator!= (const oid &o) const
	The not-equal-operator for oids.
bool	operator> (const oid &o) const
	The greater-than operator.
bool	contains (const oid &id)
	Checks whether the given oid is in the subtree of this oid.
bool	is_null () const
	Whether it is the null Object Identifier.
virtual void	update ()
	Update the internal state of the object.
virtual oid	get ()
	Obtain the current value for the object.
Public Attributes
const oid	iso_oid ("1")
	The 'iso' OID according to RFC 1155.
const oid	ccitt_oid ("0")
	The 'ccitt' OID according to RFC 1155.
const oid	joint_iso_ccitt_oid ("2")
	The 'joint.iso.ccitt' OID according to RFC 1155.
const oid	org_oid (iso_oid,"3")
	The 'iso.org' OID according to RFC 1155.
const oid	dod_oid (org_oid,"6")
	The 'iso.org.dod' OID according to RFC 1155.
const oid	internet_oid (dod_oid,"1")
	The 'iso.org.dod.internet' OID according to RFC 1155.
const oid	directory_oid (internet_oid,"1")
	The 'iso.org.dod.internet.directory' OID according to RFC 1155.
const oid	mgmt_oid (internet_oid,"2")
	The 'iso.org.dod.internet.mgmt' OID according to RFC 1155.
const oid	experimental_oid (internet_oid,"3")
	The 'iso.org.dod.internet.experimental' OID according to RFC 1155.
const oid	private_oid (internet_oid,"4")
	The 'iso.org.dod.internet.private' OID according to RFC 1155.
const oid	enterprises_oid (private_oid,"1")
	The 'iso.org.dod.internet.private.enterprises' OID according to RFC 1155.
Private Member Functions
void	parse_string (std::string s)
	Parse an OID from a string and append it.
Private Attributes
bool	include
	the 'include' field.
Friends
std::ostream &	operator<< (std::ostream &out, const agentxcpp::oid &o)
	The output operator for the oid class.

---

Detailed Description

Represents an SNMP object identifier (OID).

This class represents an OID. OID's are sequences of sub-identifiers, which are integers.

This class provides constructors taking a string which contains an OID. For example, this works:

 oid myCompany = oid("1.3.6.1.4.1.355");

Also a constructor is provided which takes an oid and a string and concatenates them, so this works also:

 oid myObject = oid(myCompany, "1.1.3.0");

In addition, some common oid's are provided as constants, e.g. 'enterprises_oid', so the following will also work (note that the second argument is a string, not an integer!):

 oid yourCompany = oid(enterprises_oid, "42"); // second param is a string!

The string given to the constructors must have a valid syntax. If a malformed string is provided, inval_param is thrown and the object is not constructed. For example, the following strings are malformed:

 "1,3,6"  // wrong separator (must be a period)
 "1.3.6." // trailing character at the end
 "1.3.6.1.4.1.123456789123" // last subid is too big (must fit in a 32 bit unsigned integer)

However, the following strings are accepted:

 "1.3.6"
 "1"  // a single subid is ok
 "1.3.6.1.4.1.42.1.0" // 0 as subid is ok
 ""   // empty string is ok

This class inherits from std:vector<uint32_t>, which means that an oid object can be manipulated the same way as a std::vector<> can be manipulated:

 oid theirCompany = enterprises_oid;
 theirCompany.push_back(23);    // Don't use a string here!

Definition at line 89 of file oid.hpp.

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Constructor & Destructor Documentation

agentxcpp::oid::oid

(

)

[inline]

Default Constructor.

This constructs an empty oid (the null oid).

The 'include' field is initialized to 'false'.

Exceptions:

None.

Definition at line 123 of file oid.hpp.

References include.

oid::oid

(

std::string

id

)

Initialize an oid object with an OID in string format.

This constructor takes a string and initializes the oid object with the OID contained within this string. The format of the string is described above.

The 'include' field is initialized to 'false'.

Parameters:

id	The initial object identifier.

Exceptions:

inval_param

If the string is malformed.

Definition at line 68 of file oid.cpp.

oid::oid	(	const oid &	o,
		std::string	id
	)

Initialize an oid object with another oid plus an OID in string format.

All subid's are copied from 'o'. Then, the OID contained within the string 'id' is appended. The format of the string is described in the documentation of this class.

The 'include' field is copied from 'o'.

Parameters:

o	The starting OID.
id	The OID to append.

Exceptions:

inval_param

If the string is malformed.

Definition at line 77 of file oid.cpp.

oid::oid	(	data_t::const_iterator &	pos,
		const data_t::const_iterator &	end,
		bool	big_endian = true
	)

Construct the object from input stream.

This constructor parses the serialized form of the object. It takes an iterator, starts parsing at the position of the iterator and advances the iterator to the position right behind the object.

The constructor expects valid data from the stream; if parsing fails, parse_error is thrown. In this case, the iterator is left at an undefined position.

Parameters:

pos	Iterator pointing to the current stream position. The iterator is advanced while reading the header.
end	Iterator pointing one element past the end of the current stream. This is needed to mark the end of the buffer.
big_endian	Whether the input stream is in big endian format

Exceptions:

parse_error

If parsing fails. In this case, the iterator is left at an undefined position.

Definition at line 189 of file oid.cpp.

---

Member Function Documentation

bool oid::contains

(

const oid &

id

)

Checks whether the given oid is in the subtree of this oid.

This method checks whether the given OID is included in the subtree which has this oid as root.

Examples:

 oid id("1.3.6.1.4.1.42.3");
 id.contains( oid(1.3.6.1.4.1.42.3) ); // true
 id.contains( oid(1.3.6.1.4.1.42) ); // false
 id.contains( oid(1.3.6.1.4.1.43.3) ); // false
 id.contains( oid(1.3.6.1.4.1.42.3.3.1) ); // true

Parameters:

id	The OID to check.

Returns:

True if id is contained in the subtree, false otherwise.

Definition at line 349 of file oid.cpp.

virtual oid agentxcpp::oid::get

(

)

[inline, virtual]

Obtain the current value for the object.

This member function is derived by classes representing SNMP variables and shall return the current value of the object.

The default implementation throws generic_error.

Returns:

The current value of the object.

Exceptions:

generic_error

If obtaining the current value fails. No other exception shall be thrown.

Definition at line 393 of file oid.hpp.

bool agentxcpp::oid::get_include

(

)

[inline]

Get the current include value.

The include value is present in the serialized form of an OID. If an OID object is created by parsing a AgentX message, the 'include' member is set accordingly.

See RFC 2741, sections 5.1 and 5.2 for details.

Definition at line 188 of file oid.hpp.

References include.

Referenced by agentxcpp::GetPDU::GetPDU().

bool oid::is_null

(

)

const

Whether it is the null Object Identifier.

According to RFC 2741, 5.1 "Object Identifier", a null object identifier has serial representation of for 4 bytes which are all set to 0. An OID with no subid's and the index field set to 0 results in that representation and is thus considered to be the null OID.

Returns:

True if the object is the null OID, false otherwise.

Definition at line 375 of file oid.cpp.

bool agentxcpp::oid::operator!=

(

const oid &

o

)

const [inline]

The not-equal-operator for oids.

See operator<() for a more detailed description about comparing OIDs.

Parameters:

o	The OID tocompare to.

Returns:

False if the OIDs are equal, true otherwise.

Definition at line 303 of file oid.hpp.

bool oid::operator<

(

const oid &

o

)

const

The less-than operator.

An OID is less than another OID if either the first not-identical part is lesser or if all parts are identical and it has lesser parts.

Example:
1.3.6.1.4.1.42.3.3.1
is less than
1.3.6.1.4.1.42.3.4.1
Note the next to last number.

Also,
1.3.6.1.4.1.42.3.3.1
is less than
1.3.6.1.4.1.42.3.3.1.1
because it is shorter.

However,
1.3.6.1.4.1.42.3.3.1
is greater than
1.3.6.1.4.1.42.3.2.1.1
because the 9th number is greater (although the first OID has less numbers than the second).

Parameters:

o	The OID tocompare to.

Returns:

True if the OID is less than 'o', false otherwise.

Definition at line 258 of file oid.cpp.

oid & oid::operator=

(

const oid &

o

)

Assignment operator.

Copies all data from 'o' into this OID.

Parameters:

o	The OID to copy from.

Returns:

A reference to this OID.

Definition at line 335 of file oid.cpp.

References include.

bool oid::operator==

(

const oid &

o

)

const

The equal-operator.

See operator<() for a more detailed description about comparing OIDs.

Parameters:

o	The OID tocompare to.

Returns:

True if the OIDs are equal, false otherwise.

Definition at line 301 of file oid.cpp.

bool agentxcpp::oid::operator>

(

const oid &

o

)

const [inline]

The greater-than operator.

See operator<() for a more detailed description about comparing OIDs.

Parameters:

o	The OID tocompare to.

Returns:

True if the OID is greater than 'o', false otherwise.

Definition at line 318 of file oid.hpp.

void oid::parse_string

(

std::string

s

)

[private]

Parse an OID from a string and append it.

The OID contained within the string 's' is parsed and appended this object. The format of the string is described above

Parameters:

s	The OID to be parsed.

Exceptions:

inval_param

If the string is malformed.

Definition at line 30 of file oid.cpp.

data_t oid::serialize

(

)

const [virtual]

Encode an OID object as described in RFC 2741, section 5.1.

Implements agentxcpp::variable.

Definition at line 118 of file oid.cpp.

Referenced by agentxcpp::UnregisterPDU::serialize(), agentxcpp::varbind::serialize(), and agentxcpp::RegisterPDU::serialize().

void agentxcpp::oid::set_include

(

bool

i

)

[inline]

set the include value

The include value is present in the serialized form of an OID. If an OID object is serialized, the include field is encoded into the stream.

See RFC 2741, sections 5.1 and 5.2 for details.

Definition at line 204 of file oid.hpp.

References include.

virtual void agentxcpp::oid::update

(

)

[inline, virtual]

Update the internal state of the object.

This function calls get() to obtain a new value and stores that value within this object.

Exceptions:

generic_error

If obtaining the new value failed.

Implements agentxcpp::variable.

Definition at line 375 of file oid.hpp.

---

Friends And Related Function Documentation

std::ostream& operator<<	(	std::ostream &	out,
		const agentxcpp::oid &	o
	)		[friend]

The output operator for the oid class.

Object identifiers (oid objects) can be output as follows:

 oid led_state(enterprises_oid, "1.3.3.1");
 cout << "LED state OID: " << led_state << endl;

The last line will output "LED state OID: .1.3.6.1.4.1.3.3.1".

Parameters:

out	The stream to which to write the output.
o	The OID to output.

Returns:

The 'out' parameter.

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Member Data Documentation

const oid ccitt_oid("0")

The 'ccitt' OID according to RFC 1155.

const oid directory_oid(internet_oid,"1")

The 'iso.org.dod.internet.directory' OID according to RFC 1155.

const oid dod_oid(org_oid,"6")

The 'iso.org.dod' OID according to RFC 1155.

const oid enterprises_oid(private_oid,"1")

The 'iso.org.dod.internet.private.enterprises' OID according to RFC 1155.

const oid experimental_oid(internet_oid,"3")

The 'iso.org.dod.internet.experimental' OID according to RFC 1155.

bool agentxcpp::oid::include [private]

the 'include' field.

Definition at line 96 of file oid.hpp.

Referenced by get_include(), oid(), operator=(), and set_include().

const oid internet_oid(dod_oid,"1")

The 'iso.org.dod.internet' OID according to RFC 1155.

const oid iso_oid("1")

The 'iso' OID according to RFC 1155.

const oid joint_iso_ccitt_oid("2")

The 'joint.iso.ccitt' OID according to RFC 1155.

const oid mgmt_oid(internet_oid,"2")

The 'iso.org.dod.internet.mgmt' OID according to RFC 1155.

const oid org_oid(iso_oid,"3")

The 'iso.org' OID according to RFC 1155.

const oid private_oid(internet_oid,"4")

The 'iso.org.dod.internet.private' OID according to RFC 1155.

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

• /home/tanjeff/projekte/agentxcpp/src/oid.hpp
• /home/tanjeff/projekte/agentxcpp/src/oid.cpp