mod_proxy_uwsgi: Add in UWSGI proxy (sub)module

                                                         -*- coding: utf-8 -*-

Changes with Apache 2.4.30

  *) mod_proxy_uwsgi: Add in UWSGI proxy (sub)module. [Roberto De Ioris,

     Jim Jagielski]

  *) mod_proxy_balancer,mod_slotmem_shm: Rework SHM reuse/deletion to not

     depend on the number of restarts (non-Unix systems) and preserve shared

     names as much as possible on configuration changes for SHMs and persisted

PATCHES ACCEPTED TO BACKPORT FROM TRUNK:

  [ start all new proposals below, under PATCHES PROPOSED. ]

  *) mod_proxy_uwsgi: Add in UWSGI proxy (sub)module

     trunk patch: http://svn.apache.org/r1810358

                  http://svn.apache.org/r1810362

                  http://svn.apache.org/r1810363

                  http://svn.apache.org/r1810365

                  http://svn.apache.org/r1810447

                  http://svn.apache.org/r1816919

                  http://svn.apache.org/r1816922

                  http://svn.apache.org/r1818013

                  http://svn.apache.org/r1818280

     2.4.x patch: trunk works (modulo CHANGES)

                  svn merge -c r1810358,r1810362,r1810363,r1810365,r1810447,r1816919,r1816922,r1818013,r1818280 ^/httpd/httpd/trunk .

                  (or svn copy ...)

     +1: jim, icing, minfrin

     icing: tested on ubuntu 16.04 with a simple uwsgi python app.

PATCHES PROPOSED TO BACKPORT FROM TRUNK:

  [ New proposals should be added at the end of the list ]

<?xml version="1.0"?>

<!DOCTYPE modulesynopsis SYSTEM "../style/modulesynopsis.dtd">

<?xml-stylesheet type="text/xsl" href="../style/manual.en.xsl"?>

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<modulesynopsis metafile="mod_proxy_uwsgi.xml.meta">

<name>mod_proxy_uwsgi</name>

<description>UWSGI gateway module for <module>mod_proxy</module></description>

<status>Extension</status>

<sourcefile>mod_proxy_uwsgi.c</sourcefile>

<identifier>proxy_uwsgi_module</identifier>

<summary>

    <p>This module <em>requires</em> the service of <module

    >mod_proxy</module>. It provides support for the

    <a href="http://uwsgi-docs.readthedocs.io/en/latest/index.html">UWSGI protocol</a>.</p>

    <p>Thus, in order to get the ability of handling the UWSGI protocol,

    <module>mod_proxy</module> and <module>mod_proxy_uwsgi</module> have to

    be present in the server.</p>

    <note type="warning"><title>Warning</title>

      <p>Do not enable proxying until you have <a

      href="mod_proxy.html#access">secured your server</a>. Open proxy

      servers are dangerous both to your network and to the Internet at

      large.</p>

    </note>

</summary>

<seealso><module>mod_proxy</module></seealso>

<seealso><module>mod_proxy_balancer</module></seealso>

<section id="examples"><title>Examples</title>

    <p>Remember, in order to make the following examples work, you have to

    enable <module>mod_proxy</module> and <module>mod_proxy_uwsgi</module>.</p>

    <example><title>Simple gateway</title>

    <highlight language="config">

ProxyPass "/uwsgi-bin/" "uwsgi://localhost:4000/"

      </highlight>

    </example>

    <p>The balanced gateway needs <module>mod_proxy_balancer</module> and

    at least one load balancer algorithm module, such as

    <module>mod_lbmethod_byrequests</module>, in addition to the proxy

    modules listed above.  <module>mod_lbmethod_byrequests</module> is the

    default, and will be used for this example configuration.</p>

    <example><title>Balanced gateway</title>

    <highlight language="config">

ProxyPass "/uwsgi-bin/" "balancer://somecluster/"

<Proxy balancer://somecluster>

    BalancerMember uwsgi://localhost:4000

    BalancerMember uwsgi://localhost:4001

</Proxy>

    </highlight>

    </example>

</section>

</modulesynopsis>

<?xml version="1.0" encoding="UTF-8" ?>

<!-- GENERATED FROM XML: DO NOT EDIT -->

<metafile reference="mod_proxy_uwsgi.xml">

  <basename>mod_proxy_uwsgi</basename>

  <path>/mod/</path>

  <relpath>..</relpath>

  <variants>

    <variant>en</variant>

  </variants>

</metafile>

proxy_http_objs="mod_proxy_http.lo"

proxy_fcgi_objs="mod_proxy_fcgi.lo"

proxy_scgi_objs="mod_proxy_scgi.lo"

proxy_uwsgi_objs="mod_proxy_uwsgi.lo"

proxy_fdpass_objs="mod_proxy_fdpass.lo"

proxy_ajp_objs="mod_proxy_ajp.lo ajp_header.lo ajp_link.lo ajp_msg.lo ajp_utils.lo"

proxy_wstunnel_objs="mod_proxy_wstunnel.lo"

    proxy_http_objs="$proxy_http_objs mod_proxy.la"

    proxy_fcgi_objs="$proxy_fcgi_objs mod_proxy.la"

    proxy_scgi_objs="$proxy_scgi_objs mod_proxy.la"

    proxy_uwsgi_objs="$proxy_uwsgi_objs mod_proxy.la"

    proxy_fdpass_objs="$proxy_fdpass_objs mod_proxy.la"

    proxy_ajp_objs="$proxy_ajp_objs mod_proxy.la"

    proxy_wstunnel_objs="$proxy_wstunnel_objs mod_proxy.la"

APACHE_MODULE(proxy_http, Apache proxy HTTP module.  Requires --enable-proxy., $proxy_http_objs, , most, , proxy)

APACHE_MODULE(proxy_fcgi, Apache proxy FastCGI module.  Requires --enable-proxy., $proxy_fcgi_objs, , most, , proxy)

APACHE_MODULE(proxy_scgi, Apache proxy SCGI module.  Requires --enable-proxy., $proxy_scgi_objs, , most, , proxy)

APACHE_MODULE(proxy_uwsgi, Apache proxy UWSGI module.  Requires --enable-proxy., $proxy_uwsgi_objs, , most, , proxy)

APACHE_MODULE(proxy_fdpass, Apache proxy to Unix Daemon Socket module.  Requires --enable-proxy., $proxy_fdpass_objs, , most, [

  AC_CHECK_DECL(CMSG_DATA,,, [

    #include <sys/types.h>