Add a BpfMap#clear method.
A caller can mostly already do this via forEach(), but having a
specific method is faster (since the code does not need to read
the value) and easier to use.
The semantics of this method (e.g., ignore ENOENT while deleting
a key, but throw on any other error) match those of the native
BpfMap::clear method.
Test: new unit tests
Change-Id: I5cd32efd0f87c823cd2d0a2fa3a95a83093fb6f9
diff --git a/Tethering/src/com/android/networkstack/tethering/BpfMap.java b/Tethering/src/com/android/networkstack/tethering/BpfMap.java
index 9a9376f..e9b4ccf 100644
--- a/Tethering/src/com/android/networkstack/tethering/BpfMap.java
+++ b/Tethering/src/com/android/networkstack/tethering/BpfMap.java
@@ -226,6 +226,20 @@
closeMap(mMapFd);
}
+ /**
+ * Clears the map. The map may already be empty.
+ *
+ * @throws ErrnoException if the map is already closed, if an error occurred during iteration,
+ * or if a non-ENOENT error occurred when deleting a key.
+ */
+ public void clear() throws ErrnoException {
+ K key = getFirstKey();
+ while (key != null) {
+ deleteEntry(key); // ignores ENOENT.
+ key = getFirstKey();
+ }
+ }
+
private static native int closeMap(int fd) throws ErrnoException;
private native int bpfFdGet(String path, int mode) throws ErrnoException, NullPointerException;
diff --git a/Tethering/tests/privileged/src/com/android/networkstack/tethering/BpfMapTest.java b/Tethering/tests/privileged/src/com/android/networkstack/tethering/BpfMapTest.java
index cceaa8c..62302c3 100644
--- a/Tethering/tests/privileged/src/com/android/networkstack/tethering/BpfMapTest.java
+++ b/Tethering/tests/privileged/src/com/android/networkstack/tethering/BpfMapTest.java
@@ -312,6 +312,32 @@
}
@Test
+ public void testClear() throws Exception {
+ // Clear an empty map.
+ assertTrue(mTestMap.isEmpty());
+ mTestMap.clear();
+
+ // Clear a map with some data in it.
+ final ArrayMap<TetherDownstream6Key, Tether6Value> resultMap =
+ new ArrayMap<>(mTestData);
+ for (int i = 0; i < resultMap.size(); i++) {
+ mTestMap.insertEntry(resultMap.keyAt(i), resultMap.valueAt(i));
+ }
+ assertFalse(mTestMap.isEmpty());
+ mTestMap.clear();
+ assertTrue(mTestMap.isEmpty());
+
+ // Clearing an already-closed map throws.
+ mTestMap.close();
+ try {
+ mTestMap.clear();
+ fail("clearing already-closed map should throw");
+ } catch (ErrnoException expected) {
+ assertEquals(OsConstants.EBADF, expected.errno);
+ }
+ }
+
+ @Test
public void testInsertOverflow() throws Exception {
final ArrayMap<TetherDownstream6Key, Tether6Value> testData =
new ArrayMap<>();