GNRC communication interface

Generic interface for IPC communication between GNRC modules.

The idea of this interface is that it provides every network module with a basic set of commands to communicate with its neighboring modules. In this model every module runs in its own thread and communication is done using the GNRC communication interface.

int gnrc_netapi_send(kernel_types.h::kernel_pid_t pid, include/net/gnrc/pkt.h::gnrc_pktsnip_t * pkt)

Shortcut function for sending netapi.h::GNRC_NETAPI_MSG_TYPE_SND messages.

Parameters

pid:PID of the targeted network module
pkt:pointer into the packet buffer holding the data to send

Return values

  • 1 if packet was successfully delivered
  • -1 on error (invalid PID or no space in queue)
int gnrc_netapi_dispatch(nettype.h::gnrc_nettype_t type, uint32_t demux_ctx, uint16_t cmd, include/net/gnrc/pkt.h::gnrc_pktsnip_t * pkt)

Sends cmd to all subscribers to (type, demux_ctx).

Parameters

type:protocol type of the targeted network module.
demux_ctx:demultiplexing context for type.
cmd:command for all subscribers
pkt:pointer into the packet buffer holding the data to send

Return values

  • Number of subscribers to (type, demux_ctx).
int gnrc_netapi_dispatch_send(nettype.h::gnrc_nettype_t type, uint32_t demux_ctx, include/net/gnrc/pkt.h::gnrc_pktsnip_t * pkt)

Sends a netapi.h::GNRC_NETAPI_MSG_TYPE_SND command to all subscribers to (type, demux_ctx).

Parameters

type:protocol type of the targeted network module.
demux_ctx:demultiplexing context for type.
pkt:pointer into the packet buffer holding the data to send

Return values

  • Number of subscribers to (type, demux_ctx).
int gnrc_netapi_receive(kernel_types.h::kernel_pid_t pid, include/net/gnrc/pkt.h::gnrc_pktsnip_t * pkt)

Shortcut function for sending netapi.h::GNRC_NETAPI_MSG_TYPE_RCV messages.

Parameters

pid:PID of the targeted network module
pkt:pointer into the packet buffer holding the received data

Return values

  • 1 if packet was successfully delivered
  • -1 on error (invalid PID or no space in queue)
int gnrc_netapi_dispatch_receive(nettype.h::gnrc_nettype_t type, uint32_t demux_ctx, include/net/gnrc/pkt.h::gnrc_pktsnip_t * pkt)

Sends a netapi.h::GNRC_NETAPI_MSG_TYPE_RCV command to all subscribers to (type, demux_ctx).

Parameters

type:protocol type of the targeted network module.
demux_ctx:demultiplexing context for type.
pkt:pointer into the packet buffer holding the data to send

Return values

  • Number of subscribers to (type, demux_ctx).
int gnrc_netapi_get(kernel_types.h::kernel_pid_t pid, netopt.h::netopt_t opt, uint16_t context, void * data, msp430_types.h::size_t max_len)

Shortcut function for sending netapi.h::GNRC_NETAPI_MSG_TYPE_GET messages and parsing the returned netapi.h::GNRC_NETAPI_MSG_TYPE_ACK message.

Parameters

pid:PID of the targeted network module
opt:option to get
context:(optional) context to the given option
data:pointer to buffer for reading the option’s value
max_len:maximum number of bytes that fit into data

Return values

  • value returned by the netapi.h::GNRC_NETAPI_MSG_TYPE_ACK message i.e. the actual length of the resulting data on success, a negative errno on error. The actual error value is for the implementation to decide but should be sensible to indicate what went wrong.
int gnrc_netapi_set(kernel_types.h::kernel_pid_t pid, netopt.h::netopt_t opt, uint16_t context, const void * data, msp430_types.h::size_t data_len)

Shortcut function for sending netapi.h::GNRC_NETAPI_MSG_TYPE_SET messages and parsing the returned netapi.h::GNRC_NETAPI_MSG_TYPE_ACK message.

Parameters

pid:PID of the targeted network module
opt:option to set
context:(optional) context to the given option
data:data to set the given option to
data_len:size of data

Return values

  • value returned by the netapi.h::GNRC_NETAPI_MSG_TYPE_ACK message i.e. 0 on success, a negative errno on error. The actual error value is for the implementation to decide but should be sensible to indicate what went wrong.
GNRC_NETAPI_MSG_TYPE_RCV

Messaging / IPC type for passing a Packet up the network stack 

1
(0x0201)
GNRC_NETAPI_MSG_TYPE_SND

Messaging / IPC type for passing a Packet down the network stack 

1
(0x0202)
GNRC_NETAPI_MSG_TYPE_SET

Messaging / IPC type for setting options of network modules 

1
(0x0203)
GNRC_NETAPI_MSG_TYPE_GET

Messaging / IPC type for getting options from network modules 

1
(0x0204)
GNRC_NETAPI_MSG_TYPE_ACK

Messaging / IPC type for replying to get and set option messages 

1
(0x0205)
struct gnrc_netapi_opt_t

Data structure to be send for setting (netapi.h::GNRC_NETAPI_MSG_TYPE_SET) and getting (netapi.h::GNRC_NETAPI_MSG_TYPE_GET) options.

netopt.h::netopt_t opt

the option to get/set

uint16_t context

(optional) context for that option

void * data

data to set or buffer to read into

uint16_t data_len

size of the data / the buffer