UCommon
Public Member Functions | Protected Member Functions
ucommon::Buffer Class Reference

A thread-safe buffer for serializing and streaming class data. More...

#include <containers.h>

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Public Member Functions

unsigned count (void) const
 Get the number of objects in the buffer currently.
 operator bool () const
 Test if there is data waiting in the buffer.
bool operator! () const
 Test if the buffer is empty.
unsigned size (void) const
 Get the size of the buffer.

Protected Member Functions

 Buffer (size_t typesize, size_t count)
 Create a buffer to hold a series of objects.
void copy (void *data)
 Copy the next object from the buffer.
bool copy (void *data, timeout_t timeout)
 Copy the next object from the buffer.
void * get (timeout_t timeout)
 Get the next object from the buffer.
void * get (void)
 Get the next object from the buffer.
virtual void * invalid (void) const
void * peek (unsigned item)
 Peek at pending data in buffer.
void put (void *data)
 Put (copy) an object into the buffer.
bool put (void *data, timeout_t timeout)
 Put (copy) an object into the buffer.
void release (void)
 Release must be called when we get an object from the buffer.
virtual ~Buffer ()
 Deallocate buffer and unblock any waiting threads.

Detailed Description

A thread-safe buffer for serializing and streaming class data.

While the queue and stack operate by managing lists of reference pointers to objects of various mixed kind, the buffer holds physical copies of objects that being passed through it, and all must be the same size. For this reason the buffer is normally used through the bufferof<type> template rather than stand-alone. The buffer is accessed in fifo order.

Author:
David Sugar <dyfet@gnutelephony.org>

Definition at line 97 of file containers.h.


Constructor & Destructor Documentation

ucommon::Buffer::Buffer ( size_t  typesize,
size_t  count 
) [protected]

Create a buffer to hold a series of objects.

Parameters:
sizeof each object in buffer.
countof objects in the buffer.

Member Function Documentation

void ucommon::Buffer::copy ( void *  data) [protected]

Copy the next object from the buffer.

This blocks until an object becomes available. Buffer is auto-released.

Parameters:
datapointer to copy into.
bool ucommon::Buffer::copy ( void *  data,
timeout_t  timeout 
) [protected]

Copy the next object from the buffer.

Buffer is auto-released.

Parameters:
datapointer to copy into.
timeoutto wait when buffer is empty in milliseconds.
Returns:
true if object copied, or false if timed out.
unsigned ucommon::Buffer::count ( void  ) const

Get the number of objects in the buffer currently.

Returns:
number of objects buffered.
void* ucommon::Buffer::get ( timeout_t  timeout) [protected]

Get the next object from the buffer.

Parameters:
timeoutto wait when buffer is empty in milliseconds.
Returns:
pointer to next object in the buffer or NULL if timed out.

Reimplemented in ucommon::bufferof< T >.

void* ucommon::Buffer::get ( void  ) [protected]

Get the next object from the buffer.

This blocks until an object becomes available.

Returns:
pointer to next object from buffer.

Reimplemented in ucommon::bufferof< T >.

ucommon::Buffer::operator bool ( ) const

Test if there is data waiting in the buffer.

Returns:
true if buffer has data.

Test if the buffer is empty.

Returns:
true if the buffer is empty.
void* ucommon::Buffer::peek ( unsigned  item) [protected]

Peek at pending data in buffer.

This returns a pointer to objects relative to the head. In effect it is the same as get() for item = 0.

Parameters:
itemto examine in buffer.
Returns:
pointer to item or NULL if invalid item number.
void ucommon::Buffer::put ( void *  data) [protected]

Put (copy) an object into the buffer.

This blocks while the buffer is full.

Parameters:
datato copy into the buffer.
bool ucommon::Buffer::put ( void *  data,
timeout_t  timeout 
) [protected]

Put (copy) an object into the buffer.

Parameters:
datato copy into the buffer.
timeoutto wait if buffer is full.
Returns:
true if copied, false if timed out while full.
void ucommon::Buffer::release ( void  ) [protected]

Release must be called when we get an object from the buffer.

This is because the pointer we return is a physical pointer to memory that is part of the buffer. The object we get cannot be removed or the memory modified while the object is being used.

unsigned ucommon::Buffer::size ( void  ) const

Get the size of the buffer.

Returns:
size of the buffer.

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