Revert "Revert "Add DhcpLeaseCallbacks""

This reverts commit e8fff42022f8c22e84d51bc093189d469bdd9af1.

Bug: 135411507
Test: atest NetworkStackTests
Change-Id: I0609301d7b37309a35c764a7551b0ca93b3faeee

3 files changed, 70 insertions, 3 deletions

diff --git a/common/networkstackclient/src/android/net/dhcp/DhcpLeaseParcelable.aidl b/common/networkstackclient/src/android/net/dhcp/DhcpLeaseParcelable.aidl
new file mode 100644
index 0000000..ba3390d
--- /dev/null
+++ b/common/networkstackclient/src/android/net/dhcp/DhcpLeaseParcelable.aidl
@@ -0,0 +1,32 @@
+/**
+ * Copyright (c) 2020, 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 perNmissions and
+ * limitations under the License.
+ */
+
+package android.net.dhcp;
+
+parcelable DhcpLeaseParcelable {
+    // Client ID of the lease; may be null.
+    byte[] clientId;
+    // MAC address provided by the client.
+    byte[] hwAddr;
+    // IPv4 address of the lease, in network byte order.
+    int netAddr;
+    // Prefix length of the lease (0-32)
+    int prefixLength;
+    // Expiration time of the lease, to compare with SystemClock.elapsedRealtime().
+    long expTime;
+    // Hostname provided by the client, if any, or null.
+    String hostname;
+}
\ No newline at end of file
diff --git a/common/networkstackclient/src/android/net/dhcp/IDhcpLeaseCallbacks.aidl b/common/networkstackclient/src/android/net/dhcp/IDhcpLeaseCallbacks.aidl
new file mode 100644
index 0000000..cf2dfa8
--- /dev/null
+++ b/common/networkstackclient/src/android/net/dhcp/IDhcpLeaseCallbacks.aidl
@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2020, 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 perNmissions and
+ * limitations under the License.
+ */
+
+package android.net.dhcp;
+
+import android.net.dhcp.DhcpLeaseParcelable;
+
+oneway interface IDhcpLeaseCallbacks {
+    /**
+     * Called when a lease is committed or released on the DHCP server.
+     *
+     * <p>This only reports lease changes after assigning a lease, or after releasing a lease
+     * following a DHCPRELEASE: this callback will not be fired when a lease just expires.
+     * @param newLeases The new list of leases tracked by the server.
+     */
+    void onLeasesChanged(in List<DhcpLeaseParcelable> newLeases);
+}
\ No newline at end of file
diff --git a/common/networkstackclient/src/android/net/dhcp/IDhcpServer.aidl b/common/networkstackclient/src/android/net/dhcp/IDhcpServer.aidl
index 559433b..dd93174 100644
--- a/common/networkstackclient/src/android/net/dhcp/IDhcpServer.aidl
+++ b/common/networkstackclient/src/android/net/dhcp/IDhcpServer.aidl
@@ -18,6 +18,7 @@ package android.net.dhcp;
 
 import android.net.INetworkStackStatusCallback;
 import android.net.dhcp.DhcpServingParamsParcel;
+import android.net.dhcp.IDhcpLeaseCallbacks;
 
 /** @hide */
 oneway interface IDhcpServer {
@@ -26,7 +27,11 @@ oneway interface IDhcpServer {
     const int STATUS_INVALID_ARGUMENT = 2;
     const int STATUS_UNKNOWN_ERROR = 3;
 
-    void start(in INetworkStackStatusCallback cb);
-    void updateParams(in DhcpServingParamsParcel params, in INetworkStackStatusCallback cb);
-    void stop(in INetworkStackStatusCallback cb);
+    void start(in INetworkStackStatusCallback cb) = 0;
+    void startWithCallbacks(in INetworkStackStatusCallback statusCb,
+        in IDhcpLeaseCallbacks leaseCb) = 3;
+    void updateParams(in DhcpServingParamsParcel params, in INetworkStackStatusCallback cb) = 1;
+    void stop(in INetworkStackStatusCallback cb) = 2;
+
+    // Next available ID: 4
 }