File syn_websocket.c¶

FileList > net > syn_websocket.c

WebSocket protocol implementation.

#include "../util/syn_assert.h"
#include "../util/syn_pack.h"
#include "syn_websocket.h"
#include <stdio.h>
#include <string.h>
#include "../util/syn_fmt.h"

Classes¶

Type	Name
struct	SYN_SHA1_Ctx SHA-1 hashing algorithm context.

Public Functions¶

Type	Name
SYN_Status	syn_websocket_send (SYN_WebsocketSession * ws, uint8_t opcode, const void * data, size_t len) Send a frame over WebSocket.
SYN_PT_Status	syn_websocket_task (SYN_PT * pt, SYN_Task * task) Background task for polling active WebSockets.
SYN_Status	syn_websocket_upgrade (const SYN_HttpdRequest * req, SYN_HttpdResponse * resp, SYN_WebsocketSession * ws, void()(const uint8_t payload, size_t len, uint8_t opcode, void ctx) on_message, void ctx) Handle upgrading a connection in an httpd route handler to WebSocket.

Public Static Functions¶

Type	Name
void	base64_encode (const uint8_t * src, size_t len, char * dst) Base64 encode a byte array.
bool	prefix_icase (const char * str, const char * prefix)
void	sha1_final (SYN_SHA1_Ctx * ctx, uint8_t digest) Finalize SHA-1 and write the 20-byte digest.
void	sha1_init (SYN_SHA1_Ctx * ctx) Initialize SHA-1 context.
void	sha1_transform (uint32_t state, const uint8_t buffer) Process a 64-byte SHA-1 block.
void	sha1_update (SYN_SHA1_Ctx * ctx, const uint8_t * data, uint32_t len) Feed data into the SHA-1 context.

Macros¶

Type	Name
define	SHA1_ROL (value, bits) `(((value) << (bits)) \\| ((value) >> (32 - (bits))))` SHA-1 rotate-left helper.

Public Functions Documentation¶

function syn_websocket_send¶

Send a frame over WebSocket.

SYN_Status syn_websocket_send (
    SYN_WebsocketSession * ws,
    uint8_t opcode,
    const void * data,
    size_t len
)

Formats a WebSocket packet header and writes the payload to the socket.

Parameters:

ws WebSocket session context.
opcode Frame type opcode (e.g., text, binary, ping).
data Payload data to send.
len Length of payload in bytes.

Returns:

SYN_OK on success, or socket error code.

function syn_websocket_task¶

Background task for polling active WebSockets.

SYN_PT_Status syn_websocket_task (
    SYN_PT * pt,
    SYN_Task * task
)

Parameters:

pt Cooperative protothread state tracker.
task Scheduler task control block.

Returns:

PT_WAITING or PT_EXITED status.

function syn_websocket_upgrade¶

Handle upgrading a connection in an httpd route handler to WebSocket.

SYN_Status syn_websocket_upgrade (
    const SYN_HttpdRequest * req,
    SYN_HttpdResponse * resp,
    SYN_WebsocketSession * ws,
    void(*)(const uint8_t *payload, size_t len, uint8_t opcode, void *ctx) on_message,
    void * ctx
)

Performs handshake, sends 101 status, sets upgraded = true on the response.

Parameters:

req Incoming HTTP upgrade request.
resp HTTP response interface to write upgrade headers to.
ws WebSocket session context to initialize.
on_message Handled frame callback function.
ctx User context pointer passed through to callback.

Returns:

SYN_OK on successful handshake, SYN_ERROR on negotiation failure.

Public Static Functions Documentation¶

function base64_encode¶

Base64 encode a byte array.

static void base64_encode (
    const uint8_t * src,
    size_t len,
    char * dst
)

Parameters:

src Source bytes.
len Number of bytes.
dst [out] Null-terminated base64 string.

function prefix_icase¶

static inline bool prefix_icase (
    const char * str,
    const char * prefix
)

function sha1_final¶

Finalize SHA-1 and write the 20-byte digest.

static void sha1_final (
    SYN_SHA1_Ctx * ctx,
    uint8_t digest
)

Parameters:

ctx SHA-1 context.
digest [out] 20-byte digest.

function sha1_init¶

Initialize SHA-1 context.

static void sha1_init (
    SYN_SHA1_Ctx * ctx
)

Parameters:

ctx SHA-1 context to initialize.

function sha1_transform¶

Process a 64-byte SHA-1 block.

static void sha1_transform (
    uint32_t state,
    const uint8_t buffer
)

Parameters:

state Running hash state.
buffer 64-byte input block.

function sha1_update¶

Feed data into the SHA-1 context.

static void sha1_update (
    SYN_SHA1_Ctx * ctx,
    const uint8_t * data,
    uint32_t len
)

Parameters:

ctx SHA-1 context.
data Input data.
len Input length.

Macro Definition Documentation¶

define SHA1_ROL¶

SHA-1 rotate-left helper.

#define SHA1_ROL (
    value,
    bits
) `(((value) << (bits)) | ((value) >> (32 - (bits))))`

The documentation for this class was generated from the following file src/syntropic/net/syn_websocket.c