lws-io-ops.h

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/*
 * libwebsockets - small server side websockets and web server implementation
 *
 * Copyright (C) 2010 - 2026 Andy Green <andy@warmcat.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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 *
 * lws-io-ops.h: the four requests the sansIO half of lws makes of the IO
 * half.  See READMEs/README.sans-io-split.md, "The interface" and "The
 * headers".
 *
 * sansIO asks IO for exactly these: call my tx when the transport can take
 * bytes, feed or stop feeding my rx, wake me at this deadline, and release
 * my transport.  It asks through the names it always has (
 * lws_callback_on_writable(), lws_rx_flow_control(), lws_set_timeout() and
 * lws_sul_schedule(), lws_close_free_wsi()); at the bottom of each, where
 * the request reaches the transport, it goes through this struct.
 *
 * IO fills it in for the normal build (lws_io_ops_default).  An embedder of
 * the sansIO half alone supplies its own in
 * lws_context_creation_info.io_ops, and a port that returns its requests as
 * polled outputs implements the same four.
 */
 
typedef struct lws_io_ops {
        int (*want_write)(struct lws *wsi);
        int (*want_read)(struct lws *wsi, int on);
        void (*deadline)(struct lws_context *cx, int tsi, lws_usec_t us);
        void (*close)(struct lws *wsi);
} lws_io_ops_t;