Mercurial > hg > nginx
view src/os/unix/ngx_socket.c @ 6536:f7849bfb6d21
Improved EPOLLRDHUP handling.
When it's known that the kernel supports EPOLLRDHUP, there is no need in
additional recv() call to get EOF or error when the flag is absent in the
event generated by the kernel. A special runtime test is done at startup
to detect if EPOLLRDHUP is actually supported by the kernel because
epoll_ctl() silently ignores unknown flags.
With this knowledge it's now possible to drop the "ready" flag for partial
read. Previously, the "ready" flag was kept until the recv() returned EOF
or error. In particular, this change allows the lingering close heuristics
(which relies on the "ready" flag state) to actually work on Linux, and not
wait for more data in most cases.
The "available" flag is now used in the read event with the semantics similar
to the corresponding counter in kqueue.
author | Valentin Bartenev <vbart@nginx.com> |
---|---|
date | Fri, 13 May 2016 17:19:23 +0300 |
parents | d620f497c50f |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> /* * ioctl(FIONBIO) sets a non-blocking mode with the single syscall * while fcntl(F_SETFL, O_NONBLOCK) needs to learn the current state * using fcntl(F_GETFL). * * ioctl() and fcntl() are syscalls at least in FreeBSD 2.x, Linux 2.2 * and Solaris 7. * * ioctl() in Linux 2.4 and 2.6 uses BKL, however, fcntl(F_SETFL) uses it too. */ #if (NGX_HAVE_FIONBIO) int ngx_nonblocking(ngx_socket_t s) { int nb; nb = 1; return ioctl(s, FIONBIO, &nb); } int ngx_blocking(ngx_socket_t s) { int nb; nb = 0; return ioctl(s, FIONBIO, &nb); } #endif #if (NGX_FREEBSD) int ngx_tcp_nopush(ngx_socket_t s) { int tcp_nopush; tcp_nopush = 1; return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (const void *) &tcp_nopush, sizeof(int)); } int ngx_tcp_push(ngx_socket_t s) { int tcp_nopush; tcp_nopush = 0; return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, (const void *) &tcp_nopush, sizeof(int)); } #elif (NGX_LINUX) int ngx_tcp_nopush(ngx_socket_t s) { int cork; cork = 1; return setsockopt(s, IPPROTO_TCP, TCP_CORK, (const void *) &cork, sizeof(int)); } int ngx_tcp_push(ngx_socket_t s) { int cork; cork = 0; return setsockopt(s, IPPROTO_TCP, TCP_CORK, (const void *) &cork, sizeof(int)); } #else int ngx_tcp_nopush(ngx_socket_t s) { return 0; } int ngx_tcp_push(ngx_socket_t s) { return 0; } #endif