Add OpenBSD support
diff --git a/src/c-ares/gen_build_yaml.py b/src/c-ares/gen_build_yaml.py
index 6f8b748..b7707dc 100755
--- a/src/c-ares/gen_build_yaml.py
+++ b/src/c-ares/gen_build_yaml.py
@@ -33,6 +33,8 @@
       return 'src/cares/cares/config_linux/ares_config.h'
     if 'darwin' in sys.platform:
       return 'src/cares/cares/config_darwin/ares_config.h'
+    if 'openbsd' in sys.platform:
+      return 'src/cares/cares/config_openbsd/ares_config.h'
     if not os.path.isfile('third_party/cares/cares/ares_config.h'):
       gen_ares_build(x)
     return 'third_party/cares/cares/ares_config.h'
@@ -125,7 +127,8 @@
         "third_party/cares/cares/setup_once.h",
         "third_party/cares/ares_build.h",
         "third_party/cares/config_linux/ares_config.h",
-        "third_party/cares/config_darwin/ares_config.h"
+        "third_party/cares/config_darwin/ares_config.h",
+        "third_party/cares/config_openbsd/ares_config.h"
     ],
   }]
 except: