WebSocket frame parser and connection pool implementation. More...

#include "websocket.h"
#include "lwip/tcp.h"
#include <string.h>

Functions
void	ws_init ()
	Initialise all WebSocket pool slots to inactive.

WsConn *	ws_alloc (uint8_t slot_id)
	Allocate a WsConn slot and bind it to a TCP slot.

WsConn *	ws_find (uint8_t slot_id)
	Find the WsConn for a given TCP slot, or nullptr if none.

void	ws_free (uint8_t slot_id)
	Free the WsConn associated with a TCP slot.

void	ws_reset_frame (WsConn *ws)
	Reset the frame parser back to WS_HEADER1, ready for the next frame.

bool	ws_send_frame (WsConn ws, WsOpcode opcode, const uint8_t payload, uint16_t len)
	Send a WebSocket frame to the client.

void	ws_close (WsConn *ws, WsCloseCode code)
	Send a Close frame and mark the slot WS_CLOSED.

void	ws_parse (WsConn *ws)
	Drain the ring buffer for slot_id and feed bytes to the WS parser.

Variables
WsConn	ws_pool [MAX_WS_CONNS]
	Pool of WebSocket connection state, one per MAX_WS_CONNS.

Detailed Description

WebSocket frame parser and connection pool implementation.

Handles RFC 6455 framing. Control frames (ping/pong/close) are handled automatically here; data frames (text/binary) are surfaced to the application layer via WS_FRAME_READY.

Automatic control frame handling

Ping -> sends Pong with the same payload immediately.
Close -> sends echoed Close frame, marks slot WS_CLOSED.
Pong -> silently discarded (keepalive response, no action needed).

Definition in file websocket.cpp.

Function Documentation

◆ ws_init()

void ws_init ( )

Initialise all WebSocket pool slots to inactive.

Called once from DetWebServer::begin().

Definition at line 24 of file websocket.cpp.

References MAX_WS_CONNS, WsConn::ws_id, and ws_pool.

Referenced by DetWebServer::begin(), and DetWebServer::stop().

◆ ws_alloc()

WsConn * ws_alloc ( uint8_t slot_id )

Allocate a WsConn slot and bind it to a TCP slot.

Parameters

slot_id TCP connection slot that just completed an upgrade.

Returns: Pointer to the allocated WsConn, or nullptr if the pool is full.

Definition at line 33 of file websocket.cpp.

References WsConn::active, MAX_WS_CONNS, WsConn::parse_state, WsConn::slot_id, WS_HEADER1, WsConn::ws_id, and ws_pool.

◆ ws_find()

WsConn * ws_find ( uint8_t slot_id )

Find the WsConn for a given TCP slot, or nullptr if none.

Parameters

slot_id TCP connection slot index.

Definition at line 50 of file websocket.cpp.

References MAX_WS_CONNS, and ws_pool.

Referenced by DetWebServer::handle().

◆ ws_free()

void ws_free ( uint8_t slot_id )

Free the WsConn associated with a TCP slot.

Parameters

slot_id TCP connection slot index.

Definition at line 60 of file websocket.cpp.

References MAX_WS_CONNS, WsConn::ws_id, and ws_pool.

Referenced by DetWebServer::handle().

◆ ws_reset_frame()

void ws_reset_frame ( WsConn * ws )

Reset the frame parser back to WS_HEADER1, ready for the next frame.

Does not change ws->active or ws->slot_id.

Parameters

ws	WebSocket connection to reset.

Definition at line 73 of file websocket.cpp.

References WsConn::buf, WsConn::fin, WsConn::len64_count, WsConn::mask_key, WsConn::masked, WsConn::opcode, WsConn::parse_state, WsConn::payload_idx, WsConn::payload_len, WS_HEADER1, and WS_OP_TEXT.

Referenced by DetWebServer::handle(), and ws_parse().

◆ ws_send_frame()

bool ws_send_frame	(	WsConn *	ws,
		WsOpcode	opcode,
		const uint8_t *	payload,
		uint16_t	len
	)

Send a WebSocket frame to the client.

Builds the header (no masking – server-to-client frames are never masked) and hands both to tcp_write(). The caller is responsible for calling tcp_output() afterwards.

Parameters

ws	WebSocket connection.
opcode	Frame opcode (WS_OP_TEXT, WS_OP_BINARY, WS_OP_PONG, etc.).
payload	Payload bytes (may be nullptr for zero-length frames).
len	Payload length in bytes.