Extract util methods

tracetools/CMakeLists.txt

@@ -42,6 +42,7 @@ include_directories(include)
 add_executable(${PROJECT_NAME}_status
   src/status.c
   src/tracetools.c
+  src/utils.cpp
 )
 target_link_libraries(${PROJECT_NAME}_status
   ${PROJECT_NAME}
@@ -57,6 +58,7 @@ install(TARGETS
 # Tracetools lib
 set(SOURCES
   src/tracetools.c
+  src/utils.cpp
 )
 if(TRACING_ENABLED)
   list(APPEND SOURCES ${LTTNG_GENERATED})

tracetools/include/tracetools/tracetools.h

@@ -158,7 +158,7 @@ void TRACEPOINT(
 void TRACEPOINT(
   rclcpp_callback_register,
   const void * callback,
-  const void * function_target);
+  const char * function_symbol);
 
 #ifdef __cplusplus
 }

tracetools/include/tracetools/utils.hpp

@@ -0,0 +1,19 @@
+#ifndef __TRACETOOLS_UTILS_H_
+#define __TRACETOOLS_UTILS_H_
+
+#include <stddef.h>
+
+template<typename T, typename... U>
+size_t get_address(std::function<T(U...)> f) {
+    typedef T(fnType)(U...);
+    fnType ** fnPointer = f.template target<fnType*>();
+    // Might be a lambda
+    if (fnPointer == nullptr) {
+        return 0;
+    }
+    return (size_t)*fnPointer;
+}
+
+const char * get_symbol(void * funptr);
+
+#endif /* __TRACETOOLS_UTILS_H_ */

tracetools/src/tracetools.c

@@ -1,4 +1,3 @@
-#include <execinfo.h>
 #include "tracetools/tracetools.h"
 
 #if defined(WITH_LTTNG) && !defined(_WIN32)
@@ -9,22 +8,6 @@
 # define CONDITIONAL_TP(...)
 #endif
 
-
-const char * get_symbol(const void * function_ptr) {
-#if defined(WITH_LTTNG) && !defined(_WIN32)
-  // If it's actually a lambda
-  if (NULL == function_ptr) {
-    return "";
-  }
-  char ** symbols = backtrace_symbols(&function_ptr, 1);
-  const char * result = symbols[0];
-  free(symbols);
-  return result;
-#else
-  return "";
-#endif
-}
-
 bool ros_trace_compile_status()
 {
 #if defined(WITH_LTTNG) && !defined(_WIN32)
@@ -171,7 +154,7 @@ void TRACEPOINT(
 void TRACEPOINT(
   rclcpp_callback_register,
   const void * callback,
-  const void * function_target)
+  const char * function_symbol)
 {
-  CONDITIONAL_TP(ros2, rclcpp_callback_register, callback, get_symbol(function_target));
+  CONDITIONAL_TP(ros2, rclcpp_callback_register, callback, function_symbol);
 }

tracetools/src/utils.cpp

@@ -0,0 +1,28 @@
+#if defined(WITH_LTTNG) && !defined(_WIN32)
+#include <dlfcn.h>
+#include <cxxabi.h>
+#endif
+
+const char * get_symbol(void * funptr) {
+#define SYMBOL_UNKNOWN "UNKNOWN"
+#if defined(WITH_LTTNG) && !defined(_WIN32)
+#define SYMBOL_LAMBDA "[lambda]"
+    if (funptr == 0) {
+        return SYMBOL_LAMBDA;
+    }
+
+    Dl_info info;
+    if (dladdr(funptr, &info) == 0) {
+        return SYMBOL_UNKNOWN;
+    }
+
+    char * demangled = nullptr;
+    int status;
+    demangled = abi::__cxa_demangle(info.dli_sname, NULL, 0, &status);
+    // Use demangled symbol if possible
+    const char * demangled_val = (status == 0 ? demangled : info.dli_sname);
+    return (demangled_val != 0 ? demangled_val : SYMBOL_UNKNOWN);
+#else
+  return SYMBOL_UNKNOWN;
+#endif
+}