Merge of r4619: accept moderation on EMFILE/ENFILE. In case of EMFILE/ENFILE returned from accept() we disable accept events, and (in case of no accept mutex used) arm timer to re-enable them later. With accept mutex we just drop it, and rely on normal accept mutex handling to re-enable accept events once it's acquired again. As we now handle errors in question, logging level was changed to "crit" (instead of "alert" used for unknown errors). Note: the code might call ngx_enable_accept_events() multiple times if there are many listen sockets. The ngx_enable_accept_events() function was modified to check if connection is already active (via c->read->active) and skip it then, thus making multiple calls safe.

# Copyright (C) Igor Sysoev
# Copyright (C) Nginx, Inc.


have=NGX_WIN32 . auto/have_headers

CORE_INCS="$WIN32_INCS"
CORE_DEPS="$WIN32_DEPS"
CORE_SRCS="$WIN32_SRCS $IOCP_SRCS"
OS_CONFIG="$WIN32_CONFIG"
CORE_LIBS="$CORE_LIBS advapi32.lib ws2_32.lib"
NGX_ICONS="$NGX_WIN32_ICONS"
SELECT_SRCS=$WIN32_SELECT_SRCS

EVENT_MODULES="$EVENT_MODULES $IOCP_MODULE"
EVENT_FOUND=YES

if [ $EVENT_SELECT = NO ]; then
    CORE_SRCS="$CORE_SRCS $SELECT_SRCS"
    EVENT_MODULES="$EVENT_MODULES $SELECT_MODULE"
fi

if [ $NGX_IPV6 = YES ]; then
    have=NGX_HAVE_INET6 . auto/have
fi

have=NGX_HAVE_AIO . auto/have
have=NGX_HAVE_IOCP . auto/have