Events: fixed EPOLLRDHUP with FIONREAD (ticket #2367). When reading exactly rev->available bytes, rev->available might become 0 after FIONREAD usage introduction in efd71d49bde0. On the next call of ngx_readv_chain() on systems with EPOLLRDHUP this resulted in return without any actions, that is, with rev->ready set, and this in turn resulted in no timers set in event pipe, leading to socket leaks. Fix is to reset rev->ready in ngx_readv_chain() when returning due to rev->available being 0 with EPOLLRDHUP, much like it is already done in ngx_unix_recv(). This ensures that if rev->available will become 0, on systems with EPOLLRDHUP support appropriate EPOLLRDHUP-specific handling will happen on the next ngx_readv_chain() call. While here, also synced ngx_readv_chain() to match ngx_unix_recv() and reset rev->ready when returning due to rev->available being 0 with kqueue. This is mostly cosmetic change, as rev->ready is anyway reset when rev->available is set to 0.

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


if [ $USE_PCRE = YES -o $PCRE != NONE ]; then
    . auto/lib/pcre/conf

else
    if [ $USE_PCRE = DISABLED -a $HTTP = YES -a $HTTP_REWRITE = YES ]; then

cat << END

$0: error: the HTTP rewrite module requires the PCRE library.
You can either disable the module by using --without-http_rewrite_module
option or you have to enable the PCRE support.

END
        exit 1
    fi
fi


if [ $USE_OPENSSL = YES ]; then
    . auto/lib/openssl/conf
fi

if [ $USE_ZLIB = YES ]; then
    . auto/lib/zlib/conf
fi

if [ $USE_LIBXSLT != NO ]; then
    . auto/lib/libxslt/conf
fi

if [ $USE_LIBGD != NO ]; then
    . auto/lib/libgd/conf
fi

if [ $USE_PERL != NO ]; then
    . auto/lib/perl/conf
fi

if [ $USE_GEOIP != NO ]; then
    . auto/lib/geoip/conf
fi

if [ $NGX_GOOGLE_PERFTOOLS = YES ]; then
    . auto/lib/google-perftools/conf
fi

if [ $NGX_LIBATOMIC != NO ]; then
    . auto/lib/libatomic/conf
fi