getdns: add optional support for libevent2

Signed-off-by: Rui Salvaterra <rsalvaterra@gmail.com>

libs/getdns/Config.in

@@ -1,6 +1,12 @@
 menu "Configuration"
 	depends on PACKAGE_getdns
 
+config GETDNS_BUILD_LIBEVENT2
+	bool "Use libevent2-based event loop"
+	default n
+	help
+		"Use libevent2 for the event loop (requires libevent2 dependency)."
+
 config GETDNS_ENABLE_STUB_ONLY
 	bool "Stub resolution mode only"
 	default y

libs/getdns/Makefile

@@ -6,7 +6,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=getdns
 PKG_VERSION:=1.7.0
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PKG_LICENSE:=BSD-3-Clause
 PKG_LICENSE_FILES:=LICENSE
@@ -19,6 +19,7 @@ PKG_HASH:=ea8713ce5e077ac76b1418ceb6afd25e6d4e39e9600f6f5e81d3a3a13a60f652
 CMAKE_INSTALL:=1
 
 PKG_CONFIG_DEPENDS:= \
+	CONFIG_GETDNS_BUILD_LIBEVENT2 \
 	CONFIG_GETDNS_ENABLE_STUB_ONLY \
 	CONFIG_GETDNS_ENABLE_IDN_LIBIDN2
 
@@ -35,7 +36,7 @@ define Package/getdns
 	SECTION:=libs
 	CATEGORY:=Libraries
 	TITLE+= (library)
-	DEPENDS+= +libopenssl +!GETDNS_ENABLE_STUB_ONLY:libunbound +GETDNS_ENABLE_IDN_LIBIDN2:libidn2
+	DEPENDS+= +libopenssl +GETDNS_BUILD_LIBEVENT2:libevent2 +!GETDNS_ENABLE_STUB_ONLY:libunbound +GETDNS_ENABLE_IDN_LIBIDN2:libidn2
 	MENU:=1
 endef
 
@@ -51,9 +52,9 @@ endef
 # CMAKE options for GetDNS are described in this document:
 # https://getdnsapi.net/quick-start/cmake-quick-start/
 CMAKE_OPTIONS += -DBUILD_LIBEV=OFF
-CMAKE_OPTIONS += -DBUILD_LIBEVENT2=OFF
 CMAKE_OPTIONS += -DBUILD_LIBUV=OFF
 
+CMAKE_OPTIONS += -DBUILD_LIBEVENT2=$(if $(CONFIG_GETDNS_BUILD_LIBEVENT2),ON,OFF)
 CMAKE_OPTIONS += -DENABLE_STUB_ONLY=$(if $(CONFIG_GETDNS_ENABLE_STUB_ONLY),ON,OFF)
 CMAKE_OPTIONS += -DUSE_LIBIDN2=$(if $(CONFIG_GETDNS_ENABLE_IDN_LIBIDN2),ON,OFF)