fdtrack: add a test.
Test: logcat -c; fdtrack_test; logcat -d | grep fdtrack
Change-Id: Ie1101c9cf968299ec1f03f20097a2ed27f6e15bd
diff --git a/libfdtrack/fdtrack.cpp b/libfdtrack/fdtrack.cpp
index 831a50d..b20e65e 100644
--- a/libfdtrack/fdtrack.cpp
+++ b/libfdtrack/fdtrack.cpp
@@ -27,6 +27,7 @@
*/
#include <inttypes.h>
+#include <stdint.h>
#include <array>
#include <mutex>
@@ -47,6 +48,11 @@
};
extern "C" void fdtrack_dump();
+
+using fdtrack_callback_t = bool (*)(int fd, const char* const* function_names,
+ const uint64_t* function_offsets, size_t count, void* arg);
+extern "C" void fdtrack_iterate(fdtrack_callback_t callback, void* arg);
+
static void fd_hook(android_fdtrack_event* event);
// Backtraces for the first 4k file descriptors ought to be enough to diagnose an fd leak.
@@ -61,6 +67,10 @@
}
__attribute__((constructor)) static void ctor() {
+ for (auto& entry : stack_traces) {
+ entry.backtrace.reserve(kStackDepth);
+ }
+
signal(BIONIC_SIGNAL_FDTRACK, [](int) { fdtrack_dump(); });
if (Unwinder().Init()) {
android_fdtrack_hook_t expected = nullptr;
@@ -97,15 +107,12 @@
}
}
-void fdtrack_dump() {
- if (!installed) {
- async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fdtrack not installed");
- } else {
- async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fdtrack dumping...");
- }
-
+void fdtrack_iterate(fdtrack_callback_t callback, void* arg) {
bool prev = android_fdtrack_set_enabled(false);
+
for (int fd = 0; fd < static_cast<int>(stack_traces.size()); ++fd) {
+ const char* function_names[kStackDepth];
+ uint64_t function_offsets[kStackDepth];
FdEntry* entry = GetFdEntry(fd);
if (!entry) {
continue;
@@ -117,26 +124,60 @@
}
if (entry->backtrace.empty()) {
+ entry->mutex.unlock();
+ continue;
+ } else if (entry->backtrace.size() < 2) {
+ async_safe_format_log(ANDROID_LOG_WARN, "fdtrack", "fd %d missing frames: size = %zu", fd,
+ entry->backtrace.size());
+
+ entry->mutex.unlock();
continue;
}
- uint64_t fdsan_owner = android_fdsan_get_owner_tag(fd);
-
- if (fdsan_owner != 0) {
- async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fd %d: (owner = %#" PRIx64 ")", fd,
- fdsan_owner);
- } else {
- async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fd %d: (unowned)", fd);
- }
-
- const size_t frame_skip = 2;
+ constexpr size_t frame_skip = 2;
for (size_t i = frame_skip; i < entry->backtrace.size(); ++i) {
- auto& frame = entry->backtrace[i];
- async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", " %zu: %s+%" PRIu64, i - frame_skip,
- frame.function_name.c_str(), frame.function_offset);
+ size_t j = i - frame_skip;
+ function_names[j] = entry->backtrace[i].function_name.c_str();
+ function_offsets[j] = entry->backtrace[i].function_offset;
}
+ bool should_continue =
+ callback(fd, function_names, function_offsets, entry->backtrace.size() - frame_skip, arg);
+
entry->mutex.unlock();
+
+ if (!should_continue) {
+ break;
+ }
}
+
android_fdtrack_set_enabled(prev);
}
+
+void fdtrack_dump() {
+ if (!installed) {
+ async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fdtrack not installed");
+ } else {
+ async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fdtrack dumping...");
+ }
+
+ fdtrack_iterate(
+ [](int fd, const char* const* function_names, const uint64_t* function_offsets, size_t count,
+ void*) {
+ uint64_t fdsan_owner = android_fdsan_get_owner_tag(fd);
+ if (fdsan_owner != 0) {
+ async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fd %d: (owner = %#" PRIx64 ")", fd,
+ fdsan_owner);
+ } else {
+ async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", "fd %d: (unowned)", fd);
+ }
+
+ for (size_t i = 0; i < count; ++i) {
+ async_safe_format_log(ANDROID_LOG_INFO, "fdtrack", " %zu: %s+%" PRIu64, i,
+ function_names[i], function_offsets[i]);
+ }
+
+ return true;
+ },
+ nullptr);
+}