From ee747e7dfa543cf77096d348aa6674365a9975c7 Mon Sep 17 00:00:00 2001
From: Tom Cherry <tomcherry@google.com>
Date: Fri, 20 Dec 2019 16:06:34 -0800
Subject: [PATCH] liblog: don't destroy global mutexes

Some objects may log when they're destructed, so don't destroy the
global std::mutex in fake_log_device.cpp.

Test: AAPT works with a log in VectorImpl::finish_vector()
Change-Id: Ie5a0ac9fc4e6a137e9516059a831e499d55d5ddb
---
 liblog/Android.bp          | 5 ++++-
 liblog/fake_log_device.cpp | 7 ++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/liblog/Android.bp b/liblog/Android.bp
index de0c636f0..bab57c084 100644
--- a/liblog/Android.bp
+++ b/liblog/Android.bp
@@ -95,7 +95,10 @@ cc_library {
         },
     },
 
-    header_libs: ["liblog_headers"],
+    header_libs: [
+        "libbase_headers",
+        "liblog_headers",
+    ],
     export_header_lib_headers: ["liblog_headers"],
 
     stubs: {
diff --git a/liblog/fake_log_device.cpp b/liblog/fake_log_device.cpp
index fb3b9bc72..2ec639358 100644
--- a/liblog/fake_log_device.cpp
+++ b/liblog/fake_log_device.cpp
@@ -31,6 +31,7 @@
 
 #include <mutex>
 
+#include <android-base/no_destructor.h>
 #include <android/log.h>
 #include <log/log_id.h>
 #include <log/logprint.h>
@@ -72,7 +73,7 @@ typedef struct LogState {
 } LogState;
 
 static LogState log_state;
-static std::mutex fake_log_mutex;
+static android::base::NoDestructor<std::mutex> fake_log_mutex;
 
 /*
  * Configure logging based on ANDROID_LOG_TAGS environment variable.  We
@@ -457,7 +458,7 @@ static int FakeWrite(log_id_t log_id, struct timespec*, struct iovec* vector, si
    * Also guarantees that only one thread is in showLog() at a given
    * time (if it matters).
    */
-  auto lock = std::lock_guard{fake_log_mutex};
+  auto lock = std::lock_guard{*fake_log_mutex};
 
   if (!log_state.initialized) {
     InitializeLogStateLocked();
@@ -519,7 +520,7 @@ static int FakeWrite(log_id_t log_id, struct timespec*, struct iovec* vector, si
  * help debug HOST tools ...
  */
 static void FakeClose() {
-  auto lock = std::lock_guard{fake_log_mutex};
+  auto lock = std::lock_guard{*fake_log_mutex};
 
   memset(&log_state, 0, sizeof(log_state));
 }