LockAgent: Add crasher binary

Add a helper that crashes with a given message.

Test: manual
Change-Id: I77e249484e65e7532045d0f8cc53ceb18d94bff5

2 files changed, 41 insertions, 0 deletions

diff --git a/tools/lock_agent/Android.bp b/tools/lock_agent/Android.bp
index c54e5b57ccc5..2125ad682bb6 100644
--- a/tools/lock_agent/Android.bp
+++ b/tools/lock_agent/Android.bp
@@ -51,11 +51,22 @@ java_library {
     installable: true,
 }
 
+cc_binary {
+    name: "lockagent_crasher",
+    srcs: ["crasher.cpp"],
+    static_libs: ["libbase_ndk"],
+    shared_libs: ["liblog"],
+    sdk_version: "current",
+    stl: "c++_static",
+    compile_multilib: "first",
+}
+
 sh_binary {
     name: "start_with_lockagent",
     src: "start_with_lockagent.sh",
     required: [
         "liblockagent",
         "lockagent",
+        "lockagent_crasher",
     ],
 }
diff --git a/tools/lock_agent/crasher.cpp b/tools/lock_agent/crasher.cpp
new file mode 100644
index 000000000000..2829d6d9447c
--- /dev/null
+++ b/tools/lock_agent/crasher.cpp
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <android-base/logging.h>
+
+// Simple binary that will just crash with the message given as the first parameter.
+//
+// This is helpful in cases the caller does not want to crash itself, e.g., fork+crash
+// instead, as LOG(FATAL) might not be safe (for example in a multi-threaded environment).
+int main(int argc, char *argv[]) {
+    if (argc != 2) {
+        LOG(FATAL) << "Need one argument for abort message";
+        __builtin_unreachable();
+    }
+    LOG(FATAL) << argv[1];
+    __builtin_unreachable();
+}