Method to avoid skipping frames for local unwinds.
In cases where there might be a crash in the unwind library itself,
we need a method to avoid skipping these frames or we won't be able
to see the actual crash.
Added unit test for this behavior.
Bug: 74121887
Test: Ran unit tests on host and target.
Change-Id: I45825020c174016af39dd8ffdc67acb72a24ad4d
diff --git a/libbacktrace/backtrace_test.cpp b/libbacktrace/backtrace_test.cpp
index aab6db9..1e3d379 100644
--- a/libbacktrace/backtrace_test.cpp
+++ b/libbacktrace/backtrace_test.cpp
@@ -69,6 +69,9 @@
// Number of simultaneous threads running in our forked process.
#define NUM_PTRACE_THREADS 5
+// The list of shared libaries that make up the backtrace library.
+static std::vector<std::string> kBacktraceLibs{"libunwindstack.so", "libbacktrace.so"};
+
struct thread_t {
pid_t tid;
int32_t state;
@@ -256,16 +259,49 @@
VERIFY_NO_ERROR(backtrace->GetError().error_code);
ASSERT_TRUE(backtrace->NumFrames() != 0);
+ // None of the frames should be in the backtrace libraries.
for (const auto& frame : *backtrace ) {
if (BacktraceMap::IsValid(frame.map)) {
const std::string name = basename(frame.map.name.c_str());
- ASSERT_TRUE(name != "libunwind.so" && name != "libbacktrace.so")
- << DumpFrames(backtrace.get());
+ for (const auto& lib : kBacktraceLibs) {
+ ASSERT_TRUE(name != lib) << DumpFrames(backtrace.get());
+ }
}
- break;
}
}
+TEST(libbacktrace, local_unwind_frames) {
+ // Verify that a local unwind with the skip frames disabled does include
+ // frames within the backtrace libraries.
+ std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), getpid()));
+ ASSERT_TRUE(backtrace.get() != nullptr);
+ backtrace->SetSkipFrames(false);
+ ASSERT_TRUE(backtrace->Unwind(0));
+ VERIFY_NO_ERROR(backtrace->GetError().error_code);
+
+ ASSERT_TRUE(backtrace->NumFrames() != 0);
+ size_t first_frame_non_backtrace_lib = 0;
+ for (const auto& frame : *backtrace) {
+ if (BacktraceMap::IsValid(frame.map)) {
+ const std::string name = basename(frame.map.name.c_str());
+ bool found = false;
+ for (const auto& lib : kBacktraceLibs) {
+ if (name == lib) {
+ found = true;
+ break;
+ }
+ }
+ if (!found) {
+ first_frame_non_backtrace_lib = frame.num;
+ break;
+ }
+ }
+ }
+
+ ASSERT_NE(0U, first_frame_non_backtrace_lib) << "No frames found in backtrace libraries:\n"
+ << DumpFrames(backtrace.get());
+}
+
TEST(libbacktrace, local_trace) {
ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelBacktrace, nullptr), 0);
}