Sock API

Provides a network API for applications and library. More...

Detailed Description

Provides a network API for applications and library.

About

+---------------+
|  Application  |
+---------------+
        ^
        |
        v
      sock
        ^
        |
        v
+---------------+
| Network Stack |
+---------------+

This module provides a set of functions to establish connections or send and receive datagrams using different types of protocols. Together, they serve as an API that allows an application or library to connect to a network.

It was designed with the following priorities in mind

1. No need for dynamic memory allocation
2. User friendliness
3. Simplicity
4. Efficiency (at both front- and backend)
5. Portability

Currently the following sock types are defined:

• sock_ip_t (net/sock/ip.h): raw IP sock
• sock_tcp_t (net/sock/tcp.h): TCP sock
• sock_udp_t (net/sock/udp.h): UDP sock
• sock_dtls_t (net/sock/dtls.h): DTLS sock

Note that there might be no relation between the different sock types. So casting e.g. sock_ip_t to sock_udp_t might not be as straight forward, as you think depending on the networking architecture.

How To Use

A RIOT application uses the functions provided by one or more of the sock type headers (for example sock_udp_t), regardless of the network stack it uses. The network stack used under the bonnet is specified by including the appropriate module (for example USEMODULE += gnrc_sock_udp for GNRC's version of this API).

This allows for network stack agnostic code on the application layer. The application code to establish a connection is always the same, allowing the network stack underneath to be switched simply by changing the USEMODULE definitions in the application's Makefile.

The actual code very much depends on the used sock type. Please refer to their documentation for specific examples.

Implementor Notes

Type definition

For simplicity and modularity this API doesn't put any restriction on the actual implementation of the type. For example, one implementation might choose to have all sock types having a common base class or use the raw IP sock type to send e.g. UDP packets, while others will keep them completely separate from each other.

Author

Alexander Aring aar@p.nosp@m.engu.nosp@m.troni.nosp@m.x.de

Simon Brummer simon.nosp@m..bru.nosp@m.mmer@.nosp@m.haw-.nosp@m.hambu.nosp@m.rg.d.nosp@m.e

Cenk Gündoğan mail@.nosp@m.cgun.nosp@m.dogan.nosp@m..de

Peter Kietzmann peter.nosp@m..kie.nosp@m.tzman.nosp@m.n@ha.nosp@m.w-ham.nosp@m.burg.nosp@m..de

Martine Lenders m.len.nosp@m.ders.nosp@m.@fu-b.nosp@m.erli.nosp@m.n.de

Kaspar Schleiser kaspa.nosp@m.r@sc.nosp@m.hleis.nosp@m.er.d.nosp@m.e

Modules
	Asynchronous sock with event API
	Provides an implementation of asynchronous sock for Event Queue.
	DNS sock API
	Sock DNS client.
	DTLS sock API
	Sock submodule for DTLS.
	Raw IPv4/IPv6 sock API
	Sock submodule for raw IPv4/IPv6.
	Sock extension for asynchronous access
	Provides backend functionality for asynchronous sock access.
	TCP sock API
	Sock submodule for TCP.
	UDP sock API
	Sock submodule for UDP.
	sock utility functions
	sock utility function

Files
file	sock.h
	Common sock API definitions.

Data Structures
struct	sock_ip_ep_t
	Abstract IP end point and end point for a raw IP sock object. More...
struct	_sock_tl_ep
	Common IP-based transport layer end point. More...

Macros
#define	SOCK_ADDR_ANY_NETIF   (0)
	Special netif ID for "any interface". More...
#define	SOCK_IPV4_EP_ANY
	Address to bind to any IPv4 address. More...
#define	SOCK_IPV6_EP_ANY
	Address to bind to any IPv6 address. More...
#define	SOCK_NO_TIMEOUT   (UINT32_MAX)
	Special value meaning "wait forever" (don't timeout)

Compile flags
Flags to (de)activate certain functionalities
#define	SOCK_HAS_IPV6
	activate IPv6 support
#define	SOCK_HAS_ASYNC
	activate asynchronous event functionality More...
#define	SOCK_HAS_ASYNC_CTX
	Activate context for asynchronous events. More...

Sock flags
Common flags for Sock API
#define	SOCK_FLAGS_REUSE_EP   (0x0001)
	allow to reuse end point on bind

Macro Definition Documentation

SOCK_ADDR_ANY_NETIF

#define SOCK_ADDR_ANY_NETIF   (0)

Special netif ID for "any interface".

Todo:

Use an equivalent definition from PR #5511

Definition at line 152 of file sock.h.

SOCK_HAS_ASYNC

#define SOCK_HAS_ASYNC

activate asynchronous event functionality

See also

Sock extension for asynchronous access

Definition at line 123 of file sock.h.

SOCK_HAS_ASYNC_CTX

#define SOCK_HAS_ASYNC_CTX

Activate context for asynchronous events.

See also

Sock extension for asynchronous access

This can be used if an asynchronous mechanism needs context (e.g. an event instance for an event loop). An event handling implementation then needs to provide a sock_async_ctx.h header file containing a definition for the sock_async_ctx_t type.

Definition at line 134 of file sock.h.

SOCK_IPV4_EP_ANY

#define SOCK_IPV4_EP_ANY

Value:

                                  { .family = AF_INET, \
                                  .netif = SOCK_ADDR_ANY_NETIF }

Address to bind to any IPv4 address.

Definition at line 157 of file sock.h.

SOCK_IPV6_EP_ANY

#define SOCK_IPV6_EP_ANY

Value:

                                  { .family = AF_INET6, \
                                  .netif = SOCK_ADDR_ANY_NETIF }

Address to bind to any IPv6 address.

Definition at line 164 of file sock.h.