From c4044355ebf3727f14b99336dcafd0e8f5f18893 Mon Sep 17 00:00:00 2001
From: Brad Ebinger <breadley@google.com>
Date: Wed, 13 Nov 2019 14:12:22 -0800
Subject: [PATCH] Fix infinite recursion due to error log message

Bug: 144446106
Test: atest TelecomUnitTests:SessionTest
Change-Id: I382f90ad6f91262b06ac8816ecf1ecabfa9f6bb6
---
 .../java/android/telecom/Logging/Session.java | 21 +++++++++++++++----
 .../telecom/Logging/SessionManager.java       | 13 +++++++++++-
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/telecomm/java/android/telecom/Logging/Session.java b/telecomm/java/android/telecom/Logging/Session.java
index 95a47e1312725..d82e93fac76d5 100644
--- a/telecomm/java/android/telecom/Logging/Session.java
+++ b/telecomm/java/android/telecom/Logging/Session.java
@@ -237,7 +237,10 @@ public class Session {
     // keep track of calls and bail if we hit the recursion limit
     private String getFullSessionId(int parentCount) {
         if (parentCount >= SESSION_RECURSION_LIMIT) {
-            Log.w(LOG_TAG, "getFullSessionId: Hit recursion limit!");
+            // Don't use Telecom's Log.w here or it will cause infinite recursion because it will
+            // try to add session information to this logging statement, which will cause it to hit
+            // this condition again and so on...
+            android.util.Slog.w(LOG_TAG, "getFullSessionId: Hit recursion limit!");
             return TRUNCATE_STRING + mSessionId;
         }
         // Cache mParentSession locally to prevent a concurrency problem where
@@ -265,7 +268,11 @@ public class Session {
         Session topNode = this;
         while (topNode.getParentSession() != null) {
             if (currParentCount >= SESSION_RECURSION_LIMIT) {
-                Log.w(LOG_TAG, "getRootSession: Hit recursion limit from " + callingMethod);
+                // Don't use Telecom's Log.w here or it will cause infinite recursion because it
+                // will try to add session information to this logging statement, which will cause
+                // it to hit this condition again and so on...
+                android.util.Slog.w(LOG_TAG, "getRootSession: Hit recursion limit from "
+                        + callingMethod);
                 break;
             }
             topNode = topNode.getParentSession();
@@ -289,7 +296,10 @@ public class Session {
     private void printSessionTree(int tabI, StringBuilder sb, int currChildCount) {
         // Prevent infinite recursion.
         if (currChildCount >= SESSION_RECURSION_LIMIT) {
-            Log.w(LOG_TAG, "printSessionTree: Hit recursion limit!");
+            // Don't use Telecom's Log.w here or it will cause infinite recursion because it will
+            // try to add session information to this logging statement, which will cause it to hit
+            // this condition again and so on...
+            android.util.Slog.w(LOG_TAG, "printSessionTree: Hit recursion limit!");
             sb.append(TRUNCATE_STRING);
             return;
         }
@@ -315,7 +325,10 @@ public class Session {
     private synchronized void getFullMethodPath(StringBuilder sb, boolean truncatePath,
             int parentCount) {
         if (parentCount >= SESSION_RECURSION_LIMIT) {
-            Log.w(LOG_TAG, "getFullMethodPath: Hit recursion limit!");
+            // Don't use Telecom's Log.w here or it will cause infinite recursion because it will
+            // try to add session information to this logging statement, which will cause it to hit
+            // this condition again and so on...
+            android.util.Slog.w(LOG_TAG, "getFullMethodPath: Hit recursion limit!");
             sb.append(TRUNCATE_STRING);
             return;
         }
diff --git a/telecomm/java/android/telecom/Logging/SessionManager.java b/telecomm/java/android/telecom/Logging/SessionManager.java
index 49c3a7205d591..ac300587cef8b 100644
--- a/telecomm/java/android/telecom/Logging/SessionManager.java
+++ b/telecomm/java/android/telecom/Logging/SessionManager.java
@@ -202,7 +202,18 @@ public class SessionManager {
         return createSubsession(false);
     }
 
-    private synchronized Session createSubsession(boolean isStartedFromActiveSession) {
+    /**
+     * Creates a new subsession based on an existing session. Will not be started until
+     * {@link #continueSession(Session, String)} or {@link #cancelSubsession(Session)} is called.
+     * <p>
+     * Only public for testing!
+     * @param isStartedFromActiveSession true if this subsession is being created for a task on the
+     *     same thread, false if it is being created for a related task on another thread.
+     * @return a new {@link Session}, call {@link #continueSession(Session, String)} to continue the
+     * session and {@link #endSession()} when done with this subsession.
+     */
+    @VisibleForTesting
+    public synchronized Session createSubsession(boolean isStartedFromActiveSession) {
         int threadId = getCallingThreadId();
         Session threadSession = mSessionMapper.get(threadId);
         if (threadSession == null) {