Support Handler/Looper for Ravenwood, with CTS.

Now that we have a solid foundation of classes available, one of the
tricker pieces is supporting Handler/Looper under Ravenwood.  At its
core, the native implementation of MessageQueue can be emulated using
core JVM primitives, which is enough to reliably pass CTS.

Advanced features like FileDescriptor events will need to wait until
we eventually have real JNI support.

Fix obscure bug with SystemClock; must be positive number.  Always
start our "fake" pointers from 1 to prevent `nullptr` oddness.

Bug: 292141694
Test: atest-dev CtsOsTestCasesRavenwood CtsOsTestCases
Change-Id: I0f82b659973443968ef2609a7e3151f381abff29

1 files changed, 17 insertions, 6 deletions

diff --git a/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java b/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java
index 79f9e58aaa1a..9db5b9895749 100644
--- a/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java
+++ b/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java
@@ -34,6 +34,8 @@ import java.util.concurrent.atomic.AtomicInteger;
 public class RavenwoodRule implements TestRule {
     private static AtomicInteger sNextPid = new AtomicInteger(100);
 
+    private static final boolean IS_UNDER_RAVENWOOD = RavenwoodRuleImpl.isUnderRavenwood();
+
     private static final int SYSTEM_UID = 1000;
     private static final int NOBODY_UID = 9999;
     private static final int FIRST_APPLICATION_UID = 10000;
@@ -45,6 +47,8 @@ public class RavenwoodRule implements TestRule {
     int mUid = NOBODY_UID;
     int mPid = sNextPid.getAndIncrement();
 
+    boolean mProvideMainThread = false;
+
     public RavenwoodRule() {
     }
 
@@ -72,6 +76,15 @@ public class RavenwoodRule implements TestRule {
             return this;
         }
 
+        /**
+         * Configure a "main" thread to be available for the duration of the test, as defined
+         * by {@code Looper.getMainLooper()}. Has no effect under non-Ravenwood environments.
+         */
+        public Builder setProvideMainThread(boolean provideMainThread) {
+            mRule.mProvideMainThread = provideMainThread;
+            return this;
+        }
+
         public RavenwoodRule build() {
             return mRule;
         }
@@ -81,8 +94,7 @@ public class RavenwoodRule implements TestRule {
      * Return if the current process is running under a Ravenwood test environment.
      */
     public boolean isUnderRavenwood() {
-        // TODO: give ourselves a better environment signal
-        return System.getProperty("java.class.path").contains("ravenwood");
+        return IS_UNDER_RAVENWOOD;
     }
 
     @Override
@@ -90,17 +102,16 @@ public class RavenwoodRule implements TestRule {
         return new Statement() {
             @Override
             public void evaluate() throws Throwable {
-                final boolean isUnderRavenwood = isUnderRavenwood();
                 if (description.getAnnotation(IgnoreUnderRavenwood.class) != null) {
-                    Assume.assumeFalse(isUnderRavenwood);
+                    Assume.assumeFalse(IS_UNDER_RAVENWOOD);
                 }
-                if (isUnderRavenwood) {
+                if (IS_UNDER_RAVENWOOD) {
                     RavenwoodRuleImpl.init(RavenwoodRule.this);
                 }
                 try {
                     base.evaluate();
                 } finally {
-                    if (isUnderRavenwood) {
+                    if (IS_UNDER_RAVENWOOD) {
                         RavenwoodRuleImpl.reset(RavenwoodRule.this);
                     }
                 }