Merge remote-tracking branch 'github/pr/1967'

diff --combined configure.ac
index b697ab9,55e80eb..ac738f8
--- 1/configure.ac
--- 2/configure.ac
+++ b/configure.ac
@@@ -3045,6 -3045,70 +3045,70 @@@ f
  AM_CONDITIONAL(BUILD_WITH_LIBMEMCACHED, test "x$with_libmemcached" = "xyes")
  # }}}
  
+ # --with-libmicrohttpd {{{
+ with_libmicrohttpd_cppflags=""
+ with_libmicrohttpd_ldflags=""
+ AC_ARG_WITH([libmicrohttpd], [AS_HELP_STRING([--with-libmicrohttpd@<:@=PREFIX@:>@], [Path to libmicrohttpd.])],
+   [
+     if test "x$withval" != "xno" && test "x$withval" != "xyes"
+     then
+       with_libmicrohttpd_cppflags="-I$withval/include"
+       with_libmicrohttpd_ldflags="-L$withval/lib"
+       with_libmicrohttpd="yes"
+     fi
+     if test "x$withval" = "xno"
+     then
+       with_libmicrohttpd="no (disabled on command line)"
+     fi
+   ],
+   [withval="yes"]
+ )
+ if test "x$withval" = "xyes"
+ then
+ PKG_CHECK_MODULES([MICROHTTPD], [libmicrohttpd],
+   [with_libmicrohttpd="yes"],
+   [with_libmicrohttpd="no (pkg-config could not find libmicrohttpd)"]
+ )
+ fi
+ 
+ if test "x$MICROHTTPD_LIBS" = "x"
+ then
+   MICROHTTPD_LIBS="-lmicrohttpd"
+ fi
+ 
+ SAVE_CPPFLAGS="$CPPFLAGS"
+ SAVE_LDFLAGS="$LDFLAGS"
+ SAVE_LIBS="$LIBS"
+ CPPFLAGS="$with_libmicrohttpd_cppflags $MICROHTTPD_CFLAGS"
+ LDFLAGS="$with_libmicrohttpd_ldflags $LDFLAGS"
+ LIBS="$LIBS $MICROHTTPD_LIBS"
+ 
+ if test "x$with_libmicrohttpd" = "xyes"
+ then
+   AC_CHECK_HEADERS([microhttpd.h],
+                    [with_libmicrohttpd="yes"],
+                    [with_libmicrohttpd="no (<microhttpd.h> not found)"])
+ fi
+ 
+ if test "x$with_libmicrohttpd" = "xyes"
+ then
+   AC_CHECK_LIB([microhttpd], [MHD_start_daemon],
+                [with_libmicrohttpd="yes"],
+                [with_libmicrohttpd="no (libmicrohttpd not found)"])
+ fi
+ 
+ CPPFLAGS="$SAVE_CPPFLAGS"
+ LDFLAGS="$SAVE_LDFLAGS"
+ LIBS="$SAVE_LIBS"
+ 
+ BUILD_WITH_LIBMICROHTTPD_CPPFLAGS="$with_libmicrohttpd_cppflags $MICROHTTPD_CFLAGS"
+ BUILD_WITH_LIBMICROHTTPD_LDFLAGS="$with_libmicrohttpd_ldflags"
+ BUILD_WITH_LIBMICROHTTPD_LIBS="$MICROHTTPD_LIBS"
+ AC_SUBST([BUILD_WITH_LIBMICROHTTPD_CPPFLAGS])
+ AC_SUBST([BUILD_WITH_LIBMICROHTTPD_LDFLAGS])
+ AC_SUBST([BUILD_WITH_LIBMICROHTTPD_LIBS])
+ # }}}
+ 
  # --with-libmodbus {{{
  with_libmodbus_config=""
  with_libmodbus_cflags=""
@@@ -4503,10 -4567,11 +4567,10 @@@ the
    if test "x$with_librdkafka_log_cb" = "xyes"
    then
          AC_DEFINE(HAVE_LIBRDKAFKA_LOG_CB, 1, [Define if librdkafka log facility is present and usable.])
 -  fi
 -  if test "x$with_librdkafka_logger" = "xyes"
 +  else if test "x$with_librdkafka_logger" = "xyes"
    then
          AC_DEFINE(HAVE_LIBRDKAFKA_LOGGER, 1, [Define if librdkafka log facility is present and usable.])
 -  fi
 +  fi; fi
  fi
  CPPFLAGS="$SAVE_CPPFLAGS"
  LDFLAGS="$SAVE_LDFLAGS"
@@@ -5877,6 -5942,7 +5941,7 @@@ plugin_virt="no
  plugin_vmem="no"
  plugin_vserver="no"
  plugin_wireless="no"
+ plugin_write_prometheus="no"
  plugin_xencpu="no"
  plugin_zfs_arc="no"
  plugin_zone="no"
@@@ -6164,6 -6230,10 +6229,10 @@@ f
  if test "x$have_protoc_c" = "xyes" && test "x$with_libprotobuf_c" = "xyes"
  then
        plugin_pinba="yes"
+       if test "x$with_libmicrohttpd" = "xyes"
+       then
+               plugin_write_prometheus="yes"
+       fi
  fi
  
  # Mac OS X memory interface
@@@ -6403,6 -6473,7 +6472,7 @@@ AC_PLUGIN([write_http],          [$with
  AC_PLUGIN([write_kafka],         [$with_librdkafka],        [Kafka output plugin])
  AC_PLUGIN([write_log],           [yes],                     [Log output plugin])
  AC_PLUGIN([write_mongodb],       [$with_libmongoc],         [MongoDB output plugin])
+ AC_PLUGIN([write_prometheus],    [$plugin_write_prometheus], [Prometheus write plugin])
  AC_PLUGIN([write_redis],         [$with_libhiredis],        [Redis output plugin])
  AC_PLUGIN([write_riemann],       [$with_libriemann_client], [Riemann output plugin])
  AC_PLUGIN([write_sensu],         [yes],                     [Sensu output plugin])
@@@ -6651,6 -6722,7 +6721,7 @@@ AC_MSG_RESULT([    libldap . . . . . . 
  AC_MSG_RESULT([    liblua  . . . . . . . $with_liblua])
  AC_MSG_RESULT([    liblvm2app  . . . . . $with_liblvm2app])
  AC_MSG_RESULT([    libmemcached  . . . . $with_libmemcached])
+ AC_MSG_RESULT([    libmicrohttpd . . . . $with_libmicrohttpd])
  AC_MSG_RESULT([    libmnl  . . . . . . . $with_libmnl])
  AC_MSG_RESULT([    libmodbus . . . . . . $with_libmodbus])
  AC_MSG_RESULT([    libmongoc . . . . . . $with_libmongoc])
@@@ -6837,6 -6909,7 +6908,7 @@@ AC_MSG_RESULT([    write_http  . . . . 
  AC_MSG_RESULT([    write_kafka . . . . . $enable_write_kafka])
  AC_MSG_RESULT([    write_log . . . . . . $enable_write_log])
  AC_MSG_RESULT([    write_mongodb . . . . $enable_write_mongodb])
+ AC_MSG_RESULT([    write_prometheus. . . $enable_write_prometheus])
  AC_MSG_RESULT([    write_redis . . . . . $enable_write_redis])
  AC_MSG_RESULT([    write_riemann . . . . $enable_write_riemann])
  AC_MSG_RESULT([    write_sensu . . . . . $enable_write_sensu])