Initialize InputEventLookup in a static function
Currently, the InputEventLookup class uses static fields, which means
that they are getting initialized early.
This causes issues with address sanitizers. The sanitizers report a
memory leak with the purely static approach. It's not clear whether this
is an actual issue, or just a bug elsewhere in the system.
To get around these problems, create a singleton instance of
InputEventLookup. This singleton will be created upon the first access
to any of its static functions. This helps resolves the sanitizer issues.
Bug: 271455682
Test: FUZZER=inputflinger_input_dispatcher_fuzzer; m $FUZZER && out/host/linux-x86/fuzz/x86_64/$FUZZER/$FUZZER
Note: test requires more CLs that are upcoming
Change-Id: Id655554db9c706f5d45eaebbee55e12519dcfdc8
diff --git a/include/input/InputEventLabels.h b/include/input/InputEventLabels.h
index 9dedd2b..909bf08 100644
--- a/include/input/InputEventLabels.h
+++ b/include/input/InputEventLabels.h
@@ -40,7 +40,16 @@
// then you must add it to InputEventLabels.cpp.
class InputEventLookup {
+ /**
+ * This class is not purely static, but uses a singleton pattern in order to delay the
+ * initialization of the maps that it contains. If it were purely static, the maps could be
+ * created early, and would cause sanitizers to report memory leaks.
+ */
public:
+ InputEventLookup(InputEventLookup& other) = delete;
+
+ void operator=(const InputEventLookup&) = delete;
+
static std::optional<int> lookupValueByLabel(const std::unordered_map<std::string, int>& map,
const char* literal);
@@ -61,17 +70,24 @@
static EvdevEventLabel getLinuxEvdevLabel(int32_t type, int32_t code, int32_t value);
private:
- static const std::unordered_map<std::string, int> KEYCODES;
+ InputEventLookup();
- static const std::vector<InputEventLabel> KEY_NAMES;
+ static const InputEventLookup& get() {
+ static InputEventLookup sLookup;
+ return sLookup;
+ }
- static const std::unordered_map<std::string, int> AXES;
+ const std::unordered_map<std::string, int> KEYCODES;
- static const std::vector<InputEventLabel> AXES_NAMES;
+ const std::vector<InputEventLabel> KEY_NAMES;
- static const std::unordered_map<std::string, int> LEDS;
+ const std::unordered_map<std::string, int> AXES;
- static const std::unordered_map<std::string, int> FLAGS;
+ const std::vector<InputEventLabel> AXES_NAMES;
+
+ const std::unordered_map<std::string, int> LEDS;
+
+ const std::unordered_map<std::string, int> FLAGS;
};
} // namespace android
diff --git a/libs/input/InputEventLabels.cpp b/libs/input/InputEventLabels.cpp
index 1c7cc12..bade686 100644
--- a/libs/input/InputEventLabels.cpp
+++ b/libs/input/InputEventLabels.cpp
@@ -434,17 +434,14 @@
// clang-format on
// --- InputEventLookup ---
-const std::unordered_map<std::string, int> InputEventLookup::KEYCODES = {KEYCODES_SEQUENCE};
-const std::vector<InputEventLabel> InputEventLookup::KEY_NAMES = {KEYCODES_SEQUENCE};
-
-const std::unordered_map<std::string, int> InputEventLookup::AXES = {AXES_SEQUENCE};
-
-const std::vector<InputEventLabel> InputEventLookup::AXES_NAMES = {AXES_SEQUENCE};
-
-const std::unordered_map<std::string, int> InputEventLookup::LEDS = {LEDS_SEQUENCE};
-
-const std::unordered_map<std::string, int> InputEventLookup::FLAGS = {FLAGS_SEQUENCE};
+InputEventLookup::InputEventLookup()
+ : KEYCODES({KEYCODES_SEQUENCE}),
+ KEY_NAMES({KEYCODES_SEQUENCE}),
+ AXES({AXES_SEQUENCE}),
+ AXES_NAMES({AXES_SEQUENCE}),
+ LEDS({LEDS_SEQUENCE}),
+ FLAGS({FLAGS_SEQUENCE}) {}
std::optional<int> InputEventLookup::lookupValueByLabel(
const std::unordered_map<std::string, int>& map, const char* literal) {
@@ -462,30 +459,36 @@
}
std::optional<int> InputEventLookup::getKeyCodeByLabel(const char* label) {
- return lookupValueByLabel(KEYCODES, label);
+ const auto& self = get();
+ return self.lookupValueByLabel(self.KEYCODES, label);
}
const char* InputEventLookup::getLabelByKeyCode(int32_t keyCode) {
- if (keyCode >= 0 && static_cast<size_t>(keyCode) < KEYCODES.size()) {
- return lookupLabelByValue(KEY_NAMES, keyCode);
+ const auto& self = get();
+ if (keyCode >= 0 && static_cast<size_t>(keyCode) < self.KEYCODES.size()) {
+ return get().lookupLabelByValue(self.KEY_NAMES, keyCode);
}
return nullptr;
}
std::optional<int> InputEventLookup::getKeyFlagByLabel(const char* label) {
- return lookupValueByLabel(FLAGS, label);
+ const auto& self = get();
+ return lookupValueByLabel(self.FLAGS, label);
}
std::optional<int> InputEventLookup::getAxisByLabel(const char* label) {
- return lookupValueByLabel(AXES, label);
+ const auto& self = get();
+ return lookupValueByLabel(self.AXES, label);
}
const char* InputEventLookup::getAxisLabel(int32_t axisId) {
- return lookupLabelByValue(AXES_NAMES, axisId);
+ const auto& self = get();
+ return lookupLabelByValue(self.AXES_NAMES, axisId);
}
std::optional<int> InputEventLookup::getLedByLabel(const char* label) {
- return lookupValueByLabel(LEDS, label);
+ const auto& self = get();
+ return lookupValueByLabel(self.LEDS, label);
}
namespace {