[Profiling] Reduce available symbols (#5195)

* Profiling - Reduce available symbols
Add a linker script to define what symbols should be published

* Fix

* Make sure the native loader can load us

---------

Co-authored-by: Gregory LEOCADIE <[email protected]>

Author: r1viollet

profiler/src/ProfilerEngine/Datadog.Profiler.Native.Linux/CMakeLists.txt

@@ -129,12 +129,16 @@ add_dependencies(${PROFILER_STATIC_LIB_NAME} libdatadog-lib libunwind-lib corecl
 # ******************************************************
 # Define shared target
 # ******************************************************
+set(dd_profiling_linker_script "${CMAKE_CURRENT_SOURCE_DIR}/datadog_profiling.version")
 
 add_library(${PROFILER_SHARED_LIB_NAME} SHARED
     ../Datadog.Profiler.Native/DllMain.cpp
 )
 
 set_target_properties(${PROFILER_SHARED_LIB_NAME} PROPERTIES PREFIX "")
+set_target_properties(${PROFILER_SHARED_LIB_NAME} PROPERTIES LINK_DEPENDS "${dd_profiling_linker_script}")
+target_link_options(${PROFILER_SHARED_LIB_NAME} PRIVATE
+                    "LINKER:--version-script=${dd_profiling_linker_script}")
 
 # Define linker libraries
 target_link_libraries(${PROFILER_SHARED_LIB_NAME}

profiler/src/ProfilerEngine/Datadog.Profiler.Native.Linux/datadog_profiling.version

@@ -0,0 +1,4 @@
+{
+  global: GetNativeProfilerIsReadyPtr; GetPointerToNativeTraceContext; Profiler_Version; SetApplicationInfoForAppDomain; SetEndpointForTrace; SetGitMetadataForApplication; ThreadsCpuManager_Map; DllGetClassObject; DllCanUnloadNow;
+  local: *;
+};