Thread-safe hash table for fd (file descriptor) related data. More...

#include <fd_data_map.hh>

Public Types
typedef T	value_type

typedef CSharedPtr< value_type >	pointer

Public Member Functions
	CFdDataMap (size_t capacity=100)
	Initialize this object. More...

size_t	size () const
	Get number of key/value pairs. More...

size_t	capacity () const
	Get current capacity. More...

void	capacity (size_t c)
	Set current capacity. More...

void	setData (int fd, const pointer &data, pointer *old=NULL)
	Set value for an fd. More...

pointer	getData (int fd) const
	Get value for an fd. More...

void	getData (int fd, pointer *data) const
	Get value for an fd. More...

template<class ForwardIter , class OutputIter >
void	getData (ForwardIter first, ForwardIter last, OutputIter dstFirst) const
	Get values for some file descriptors. More...

void	clearData (int fd, pointer *old=NULL)
	Remove value for an fd. More...

template<class ForwardIter >
void	clearData (ForwardIter first, ForwardIter last)
	Remove values for some file descriptors. More...

template<class ForwardIter , class OutputIter >
void	clearData (ForwardIter first, ForwardIter last, OutputIter dstFirst)
	Remove values for some file descriptors. More...

void	clear ()
	Clear all key/value pairs.

Detailed Description

template<class T, class LockT = CSpinLock>
class CFdDataMap< T, LockT >

Thread-safe hash table for fd (file descriptor) related data.

Key MUST be file descriptors, which are non-negative and of type int. In fact the file descriptor acts as an index to an underlying vector of values. Because the number of files a process can open is limited, e.g. 1024 (it is modifiable), there's no chance for the underlying vector to grow unexpectedly. So do NOT use CFdDataMap as a generic int to value hash table.
Value can be of any type, even non-copyable types. Usually you want to keep a session for each socket fd, and the session is non-copyable. CFdDataMap uses smart pointer to hold a value, there are several advantages. Firstly, it avoids copying issue as mentioned; secondly, it simplifies lifetime control for each value among multiple threads; And finally, it is efficient for the underlying vector to expand.
CFdDataMap is thread safe and implemented on top of CFdMap. You can specify any lock type you want, as long as it cooperates with CGuard.

Template Parameters

T	Value type
LockT	Lock type, default to CSpinLock

See also: CFdMap

Constructor & Destructor Documentation

template<class T , class LockT = CSpinLock>

CFdDataMap< T, LockT >::CFdDataMap ( size_t capacity = 100 )

inlineexplicit

Initialize this object.

capacity is used as a hint to the number of key/value pairs this object wants to hold. But CFdDataMap is free to expand as needed.

Parameters

capacity Initial reserved room for key/value pairs

Member Function Documentation

template<class T , class LockT = CSpinLock>

size_t CFdDataMap< T, LockT >::capacity ( ) const

inline

Get current capacity.

Returns: Current capacity

template<class T , class LockT = CSpinLock>

void CFdDataMap< T, LockT >::capacity ( size_t c )

inline

Set current capacity.

Parameters

c	New capacity

template<class T , class LockT = CSpinLock>

void CFdDataMap< T, LockT >::clearData	(	int	fd,
		pointer *	old = `NULL`
	)

inline

Remove value for an fd.

Parameters

[in]	fd	A file descriptor
[out]	old	A smart pointer object to obtain old value for `fd`, or `NULL` if not interested

template<class T , class LockT = CSpinLock>

template<class ForwardIter >

void CFdDataMap< T, LockT >::clearData	(	ForwardIter	first,
		ForwardIter	last
	)

inline

Remove values for some file descriptors.

Parameters

[in]	first	Begin iterator for a collection of file descriptors
[in]	last	End iterator for a collection of file descriptors

template<class T , class LockT = CSpinLock>

template<class ForwardIter , class OutputIter >

void CFdDataMap< T, LockT >::clearData	(	ForwardIter	first,
		ForwardIter	last,
		OutputIter	dstFirst
	)

inline

Remove values for some file descriptors.

Parameters

[in]	first	Begin iterator for a collection of file descriptors
[in]	last	End iterator for a collection of file descriptors
[out]	dstFirst	Begin iterator for a collection of smart pointers to receive old values

Note: The size and validation of destination collection is guaranteed by the user.

template<class T , class LockT = CSpinLock>

pointer CFdDataMap< T, LockT >::getData ( int fd ) const

inline

Get value for an fd.

Parameters

fd	A file descriptor

Returns: A smart pointer object hold the value for fd

template<class T , class LockT = CSpinLock>

void CFdDataMap< T, LockT >::getData	(	int	fd,
		pointer *	data
	)		const

inline

Get value for an fd.

Parameters

[in]	fd	A file descriptor
[out]	data	A smart pointer object to obtain the value for `fd`

template<class T , class LockT = CSpinLock>

template<class ForwardIter , class OutputIter >

void CFdDataMap< T, LockT >::getData	(	ForwardIter	first,
		ForwardIter	last,
		OutputIter	dstFirst
	)		const

inline

Get values for some file descriptors.

This function saves many lock/unlock operations.
Example code:

CFdDataMap<Data> fdmap;
vector<int> fds;
vector<CFdDataMap<Data>::pointer> values(fds.size());
fdmap.getData(fds.begin(), fds.end(), values.begin());

Parameters

[in]	first	Begin iterator for a collection of file descriptors
[in]	last	End iterator for a collection of file descriptors
[out]	dstFirst	Begin iterator for a collection of smart pointers to receive the values of file descriptors

Note: The size and validation of destination collection is guaranteed by the user.

template<class T, class LockT = CSpinLock>

void CFdDataMap< T, LockT >::setData	(	int	fd,
		const pointer &	data,
		pointer *	old = `NULL`
	)

inline

Set value for an fd.

Parameters

[in]	fd	A file descriptor
[in]	data	New value for `fd`
[out]	old	A smart pointer object to obtain old value for `fd`

template<class T, class LockT = CSpinLock>

size_t CFdDataMap< T, LockT >::size ( ) const

inline

Get number of key/value pairs.

Returns: Number of key/value pairs

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

fd_data_map.hh

Public Types

Public Member Functions

Detailed Description

template<class T, class LockT = CSpinLock> class CFdDataMap< T, LockT >

Constructor & Destructor Documentation

Member Function Documentation

template<class T, class LockT = CSpinLock>
class CFdDataMap< T, LockT >