Expose methods for holding/resuming interruptions

These will be needed to implement the dir interruption workaround.

ext/datadog_profiling_native_extension/collectors_cpu_and_wall_time_worker.c

@@ -222,6 +222,8 @@ static VALUE _native_with_blocked_sigprof(DDTRACE_UNUSED VALUE self);
 static VALUE rescued_sample_allocation(VALUE tracepoint_data);
 static void delayed_error(struct cpu_and_wall_time_worker_state *state, const char *error);
 static VALUE _native_delayed_error(DDTRACE_UNUSED VALUE self, VALUE instance, VALUE error_msg);
+static VALUE _native_hold_interruptions(DDTRACE_UNUSED VALUE self);
+static VALUE _native_resume_interruptions(DDTRACE_UNUSED VALUE self);
 
 // Note on sampler global state safety:
 //
@@ -285,7 +287,9 @@ void collectors_cpu_and_wall_time_worker_init(VALUE profiling_module) {
   rb_define_singleton_method(collectors_cpu_and_wall_time_worker_class, "_native_allocation_count", _native_allocation_count, 0);
   rb_define_singleton_method(collectors_cpu_and_wall_time_worker_class, "_native_is_running?", _native_is_running, 1);
   rb_define_singleton_method(testing_module, "_native_current_sigprof_signal_handler", _native_current_sigprof_signal_handler, 0);
-  // TODO: Remove `_native_is_running` from `testing_module` once `prof-correctness` has been updated to not need it
+  rb_define_singleton_method(collectors_cpu_and_wall_time_worker_class, "_native_hold_interruptions", _native_hold_interruptions, 0);
+  rb_define_singleton_method(collectors_cpu_and_wall_time_worker_class, "_native_resume_interruptions", _native_resume_interruptions, 0);
+  // TODO: Remove `_native_is_running` from `testing_module` (should be in class) once `prof-correctness` has been updated to not need it
   rb_define_singleton_method(testing_module, "_native_is_running?", _native_is_running, 1);
   rb_define_singleton_method(testing_module, "_native_install_testing_signal_handler", _native_install_testing_signal_handler, 0);
   rb_define_singleton_method(testing_module, "_native_remove_testing_signal_handler", _native_remove_testing_signal_handler, 0);
@@ -1159,3 +1163,17 @@ static VALUE _native_delayed_error(DDTRACE_UNUSED VALUE self, VALUE instance, VA
 
   return Qnil;
 }
+
+// Masks SIGPROF interruptions for the current thread. Please don't use this -- you may end up with incomplete
+// profiling data.
+static VALUE _native_hold_interruptions(DDTRACE_UNUSED VALUE self) {
+  block_sigprof_signal_handler_from_running_in_current_thread();
+  return Qtrue;
+}
+
+// Unmasks SIGPROF interruptions for the current thread. If there's a pending sample, it'll be triggered inside this
+// method.
+static VALUE _native_resume_interruptions(DDTRACE_UNUSED VALUE self) {
+  unblock_sigprof_signal_handler_from_running_in_current_thread();
+  return Qtrue;
+}

sig/datadog/profiling.rbs

@@ -6,6 +6,9 @@ module Datadog
     def self.allocation_count: () -> ::Integer?
     def self.enabled?: () -> bool
     def self.wait_until_running: () -> true
+
+    private
+
     def self.replace_noop_allocation_count: () -> void
     def self.native_library_compilation_skipped?: () -> ::String?
     def self.try_reading_skipped_reason_file: (?untyped file_api) -> ::String?

sig/datadog/profiling/collectors/cpu_and_wall_time_worker.rbs

@@ -44,6 +44,8 @@ module Datadog
         def self._native_is_running?: (CpuAndWallTimeWorker self_instance) -> bool
         def self._native_allocation_count: () -> ::Integer?
         def self._native_sampling_loop: (CpuAndWallTimeWorker self_instance) -> void
+        def self._native_hold_interruptions: () -> void
+        def self._native_resume_interruptions: () -> void
 
         def wait_until_running: (timeout_seconds: ::Integer?) -> true
       end

spec/datadog/profiling/collectors/cpu_and_wall_time_worker_spec.rb

@@ -1176,6 +1176,20 @@
     end
   end
 
+  describe '._native_hold_interruptions and _native_resume_interruptions' do
+    it 'blocks/unblocks interruptions for the current thread' do
+      expect(described_class::Testing._native_is_sigprof_blocked_in_current_thread).to be false
+
+      described_class._native_hold_interruptions
+
+      expect(described_class::Testing._native_is_sigprof_blocked_in_current_thread).to be true
+
+      described_class._native_resume_interruptions
+
+      expect(described_class::Testing._native_is_sigprof_blocked_in_current_thread).to be false
+    end
+  end
+
   def wait_until_running
     cpu_and_wall_time_worker.wait_until_running
   end