I/O & Event Management

Detailed Description

The core event management system.

This defines all the different types of file descriptors that can be used by the SelectServer. At the top level, the ReadFileDescriptor / WriteFileDescriptor interfaces provide the minimum functionality needed to register a socket with the SelectServer to handle read / write events. The BidirectionalFileDescriptor extends this interface to handle both reading and writing.

The UnmanagedFileDescriptor allows socket descriptors created by other libraries to be used with the SelectServer.

ConnectedDescriptor is a socket with tighter intergration with the SelectServer. This allows the SelectServer to detect when the socket is closed and call the OnClose() handler. It also provides methods to disable SIGPIPE, control the blocking attributes and check how much data remains to be read. ConnectedDescriptor has the following sub-classes:

• LoopbackDescriptor this socket is just a pipe(). Data written to the socket is available to be read.
• PipeDescriptor allows a pair of sockets to be created. Data written to socket A is available at FileDescriptor B and visa versa.
• UnixSocket, similar to PipeDescriptor but uses unix domain sockets.
• DeviceDescriptor, this is a generic ConnectedDescriptor. It can be used with file descriptors to handle local devices.

Files
file	Descriptor.h

Classes
class	ola::io::ReadFileDescriptor
	Represents a file descriptor that supports reading data. More...
class	ola::io::WriteFileDescriptor
	Represents a file descriptor that supports writing data. More...
class	ola::io::BidirectionalFileDescriptor
	A file descriptor that supports both read & write. More...
class	ola::io::UnmanagedFileDescriptor
	Allows a FD created by a library to be used with the SelectServer. More...
struct	ola::io::UnmanagedFileDescriptor_lt
	Comparison operator for UnmanagedFileDescriptor. More...
class	ola::io::ConnectedDescriptor
	A BidirectionalFileDescriptor that also generates notifications when closed. More...
class	ola::io::LoopbackDescriptor
	A loopback descriptor. More...
class	ola::io::PipeDescriptor
	A descriptor that uses unix pipes. More...
class	ola::io::UnixSocket
	A unix domain socket pair. More...
class	ola::io::DeviceDescriptor
	A descriptor which represents a connection to a device. More...

Functions
int	ola::io::ToFD (const DescriptorHandle &handle)

Function Documentation

int ola::io::ToFD

(

const DescriptorHandle &

handle

)

Helper function to convert a DescriptorHandle to a file descriptor.

Parameters

handle

The descriptor handle

Returns

-1 on error, file descriptor otherwise