Add a command to call libnetutils' do_dhcp.

Useful for wifi bringup.

Change-Id: Ib1d1b1d15cb9ce57119457a780e169b8f98987c2

libnetutils/Android.mk

@@ -17,3 +17,10 @@ LOCAL_MODULE := libnetutils
 LOCAL_CFLAGS := -Werror
 
 include $(BUILD_SHARED_LIBRARY)
+
+include $(CLEAR_VARS)
+LOCAL_SRC_FILES := dhcptool.c
+LOCAL_SHARED_LIBRARIES := libnetutils
+LOCAL_MODULE := dhcptool
+LOCAL_MODULE_TAGS := debug
+include $(BUILD_EXECUTABLE)

libnetutils/dhcptool.c

+/*
+ * Copyright 2015, The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <error.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+#include <netutils/dhcp.h>
+#include <netutils/ifc.h>
+
+int main(int argc, char* argv[]) {
+  if (argc != 2) {
+    error(EXIT_FAILURE, 0, "usage: %s INTERFACE", argv[0]);
+  }
+
+  char* interface = argv[1];
+  if (ifc_init()) {
+    error(EXIT_FAILURE, errno, "dhcptool %s: ifc_init failed", interface);
+  }
+
+  int rc = do_dhcp(interface);
+  if (rc) {
+    error(0, errno, "dhcptool %s: do_dhcp failed", interface);
+  }
+
+  ifc_close();
+
+  return rc ? EXIT_FAILURE : EXIT_SUCCESS;
+}