Conditional compilation with libevent-openssl

Require Libevent-openssl 2.0.8 because we use
evconnlistener_set_error_cb().

configure.ac

@@ -96,12 +96,15 @@ if test "x${have_openssl}" = "xno"; then
 fi
 
 # libevent_openssl
-PKG_CHECK_MODULES([LIBEVENT_OPENSSL], [libevent_openssl >= 2.0.6],
+# 2.0.8 is required because we use evconnlistener_set_error_cb()
+PKG_CHECK_MODULES([LIBEVENT_OPENSSL], [libevent_openssl >= 2.0.8],
                   [have_libevent_openssl=yes], [have_libevent_openssl=no])
 if test "x${have_libevent_openssl}" = "xno"; then
   AC_MSG_NOTICE($LIBEVENT_OPENSSL_PKG_ERRORS)
   AC_MSG_NOTICE([Shrpx example program will not be built.])
 fi
+AM_CONDITIONAL([HAVE_LIBEVENT_OPENSSL],
+               [ test "x${have_libevent_openssl}" = "xyes" ])
 
 # libxml2 (for examples/spdycat)
 AM_PATH_XML2(2.7.7, [have_libxml2=yes], [have_libxml2=no])
@@ -186,5 +189,6 @@ AC_MSG_NOTICE([summary of build options:
     CUnit:          ${have_cunit}
     OpenSSL:        ${have_openssl}
     Libxml2:        ${have_libxml2}
+    Libevent(SSL):  ${have_libevent_openssl}
     Examples:       ${enable_examples}
 ])

examples/Makefile.am

@@ -29,7 +29,11 @@ AM_CPPFLAGS = -Wall -I$(srcdir)/../lib/includes -I$(builddir)/../lib/includes \
 AM_LDFLAGS = @OPENSSL_LIBS@ @XML_LIBS@ @LIBEVENT_OPENSSL_LIBS@
 LDADD = $(top_builddir)/lib/libspdylay.la
 
-bin_PROGRAMS = spdycat spdyd shrpx
+bin_PROGRAMS = spdycat spdyd
+
+if HAVE_LIBEVENT_OPENSSL
+bin_PROGRAMS += shrpx
+endif # HAVE_LIBEVENT_OPENSSL
 
 HELPER_OBJECTS = uri.cc util.cc spdylay_ssl.cc
 HELPER_HFILES = uri.h util.h spdylay_ssl.h
@@ -65,6 +69,7 @@ spdyd_SOURCES = ${HELPER_OBJECTS} ${HELPER_HFILES} \
 	${SPDY_SERVER_OBJECTS} ${SPDY_SERVER_HFILES} \
 	spdyd.cc
 
+if HAVE_LIBEVENT_OPENSSL
 shrpx_SOURCES = ${HELPER_OBJECTS} ${HELPER_HFILES} \
 	shrpx_config.cc shrpx_config.h \
 	shrpx.cc \
@@ -82,6 +87,7 @@ shrpx_SOURCES = ${HELPER_OBJECTS} ${HELPER_HFILES} \
 	shrpx_thread_event_receiver.cc shrpx_thread_event_receiver.h \
 	shrpx_worker.cc shrpx_worker.h \
 	htparse/htparse.c htparse/htparse.h
+endif # HAVE_LIBEVENT_OPENSSL
 
 noinst_PROGRAMS = spdycli
 spdycli_SOURCES = spdycli.c