Add lock to protect UnwantedInteractionBlocker

The call to 'dump' may come from any thread, and therefore could cause a
crash. Add a lock to protect this input stage.

To run the test:
adb shell -t "/data/nativetest64/inputflinger_tests/inputflinger_tests --gtest_filter='*Dump*' --gtest_repeat=100000 --gtest_break_on_failure"

Before this patch, the test failed after ~5K - ~13K iterations (took
10-20 seconds to crash).

Bug: 232645962
Test: m inputflinger_tests && adb sync data && <run the test>
Change-Id: I2a199690450bc5bb4a8576aa59075e99d37a531b

1 files changed, 17 insertions, 0 deletions

diff --git a/libs/input/PrintTools.cpp b/libs/input/PrintTools.cpp
index 5d6ae4ed91..01f6bf514b 100644
--- a/libs/input/PrintTools.cpp
+++ b/libs/input/PrintTools.cpp
@@ -17,6 +17,7 @@
 #define LOG_TAG "PrintTools"
 
 #include <input/PrintTools.h>
+#include <sstream>
 
 namespace android {
 
@@ -24,4 +25,20 @@ const char* toString(bool value) {
     return value ? "true" : "false";
 }
 
+std::string addLinePrefix(std::string str, const std::string& prefix) {
+    std::stringstream ss;
+    bool newLineStarted = true;
+    for (const auto& ch : str) {
+        if (newLineStarted) {
+            ss << prefix;
+            newLineStarted = false;
+        }
+        if (ch == '\n') {
+            newLineStarted = true;
+        }
+        ss << ch;
+    }
+    return ss.str();
+}
+
 } // namespace android