Mercurial > hg > nginx

view src/os/unix/ngx_socket.h @ 7583:efd71d49bde0

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Events: available bytes calculation via ioctl(FIONREAD). This makes it possible to avoid looping for a long time while working with a fast enough peer when data are added to the socket buffer faster than we are able to read and process them (ticket #1431). This is basically what we already do on FreeBSD with kqueue, where information about the number of bytes in the socket buffer is returned by the kevent() call. With other event methods rev->available is now set to -1 when the socket is ready for reading. Later in ngx_recv() and ngx_recv_chain(), if full buffer is received, real number of bytes in the socket buffer is retrieved using ioctl(FIONREAD). Reading more than this number of bytes ensures that even with edge-triggered event methods the event will be triggered again, so it is safe to stop processing of the socket and switch to other connections. Using ioctl(FIONREAD) only after reading a full buffer is an optimization. With this approach we only call ioctl(FIONREAD) when there are at least two recv()/readv() calls.
author Maxim Dounin <mdounin@mdounin.ru>
date Thu, 17 Oct 2019 16:02:19 +0300
parents d620f497c50f
children 23880e4ad3e2
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_SOCKET_H_INCLUDED_
#define _NGX_SOCKET_H_INCLUDED_


#include <ngx_config.h>


#define NGX_WRITE_SHUTDOWN SHUT_WR

typedef int  ngx_socket_t;

#define ngx_socket          socket
#define ngx_socket_n        "socket()"


#if (NGX_HAVE_FIONBIO)

int ngx_nonblocking(ngx_socket_t s);
int ngx_blocking(ngx_socket_t s);

#define ngx_nonblocking_n   "ioctl(FIONBIO)"
#define ngx_blocking_n      "ioctl(!FIONBIO)"

#else

#define ngx_nonblocking(s)  fcntl(s, F_SETFL, fcntl(s, F_GETFL) | O_NONBLOCK)
#define ngx_nonblocking_n   "fcntl(O_NONBLOCK)"

#define ngx_blocking(s)     fcntl(s, F_SETFL, fcntl(s, F_GETFL) & ~O_NONBLOCK)
#define ngx_blocking_n      "fcntl(!O_NONBLOCK)"

#endif

#if (NGX_HAVE_FIONREAD)

#define ngx_socket_nread(s, n)  ioctl(s, FIONREAD, n)
#define ngx_socket_nread_n      "ioctl(FIONREAD)"

#endif

int ngx_tcp_nopush(ngx_socket_t s);
int ngx_tcp_push(ngx_socket_t s);

#if (NGX_LINUX)

#define ngx_tcp_nopush_n   "setsockopt(TCP_CORK)"
#define ngx_tcp_push_n     "setsockopt(!TCP_CORK)"

#else

#define ngx_tcp_nopush_n   "setsockopt(TCP_NOPUSH)"
#define ngx_tcp_push_n     "setsockopt(!TCP_NOPUSH)"

#endif


#define ngx_shutdown_socket    shutdown
#define ngx_shutdown_socket_n  "shutdown()"

#define ngx_close_socket    close
#define ngx_close_socket_n  "close() socket"


#endif /* _NGX_SOCKET_H_INCLUDED_ */