QUIC: coalesce neighbouring stream send buffers. Previously a single STREAM frame was created for each buffer in stream output chain which is wasteful with respect to memory. The following changes were made in the stream send code: - ngx_quic_stream_send_chain() no longer calls ngx_quic_stream_send() and got a separate implementation that coalesces neighbouring buffers into a single frame - the new ngx_quic_stream_send_chain() respects the limit argument, which fixes sendfile_max_chunk and limit_rate - ngx_quic_stream_send() is reimplemented to call ngx_quic_stream_send_chain() - stream frame size limit is moved out to a separate function ngx_quic_max_stream_frame() - flow control is moved out to a separate function ngx_quic_max_stream_flow() - ngx_quic_stream_send_chain() is relocated next to ngx_quic_stream_send()

/*
 * Copyright (C) Ruslan Ermilov
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_RWLOCK_H_INCLUDED_
#define _NGX_RWLOCK_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


void ngx_rwlock_wlock(ngx_atomic_t *lock);
void ngx_rwlock_rlock(ngx_atomic_t *lock);
void ngx_rwlock_unlock(ngx_atomic_t *lock);
void ngx_rwlock_downgrade(ngx_atomic_t *lock);


#endif /* _NGX_RWLOCK_H_INCLUDED_ */