Only function and file names and limited num frames

Author: gyuheon0h

ext/libdatadog_api/crashtracker.c

@@ -175,19 +175,13 @@ static VALUE _native_stop(DDTRACE_UNUSED VALUE _self) {
   return Qtrue;
 }
 
-// Ruby runtime stack callback implementation
-// This function will be called by libdatadog during crash handling
+
 static void ruby_runtime_stack_callback(
   void (*emit_frame)(const ddog_crasht_RuntimeStackFrame*),
   void (*emit_stacktrace_string)(const char*)
 ) {
-  // Only using emit_frame - ignore emit_stacktrace_string parameter
   (void)emit_stacktrace_string;
 
-  // Try to safely walk Ruby stack using direct VM structure access
-  // Avoid Ruby API calls that might hang in crash context
-
-  // First emit a marker frame to show callback is working
   ddog_crasht_RuntimeStackFrame marker_frame = {
     .function_name = "ruby_stack_walker_start",
     .file_name = "crashtracker.c",
@@ -196,7 +190,6 @@ static void ruby_runtime_stack_callback(
   };
   emit_frame(&marker_frame);
 
-  // Try to get current thread and execution context safely
   VALUE current_thread = rb_thread_current();
   if (current_thread == Qnil) return;
 
@@ -222,40 +215,43 @@ static void ruby_runtime_stack_callback(
 
   if (!cfp || !end_cfp) return;
 
-  // Skip dummy frames
   end_cfp = RUBY_VM_NEXT_CONTROL_FRAME(end_cfp);
   if (end_cfp <= cfp) return;
 
-  // Walk stack frames with extreme caution
   int frame_count = 0;
-  const int MAX_FRAMES = 10; // Keep very low to minimize crash risk
+  const int MAX_FRAMES = 15;
 
   for (; cfp != RUBY_VM_NEXT_CONTROL_FRAME(end_cfp) && frame_count < MAX_FRAMES;
        cfp = RUBY_VM_NEXT_CONTROL_FRAME(cfp)) {
 
     if (VM_FRAME_RUBYFRAME_P(cfp) && cfp->iseq) {
-      // Instead of calling rb_iseq_* functions, work directly with iseq struct
       const rb_iseq_t *iseq = cfp->iseq;
 
-      // Basic frame info without risky API calls
-      char frame_desc[64];
-      snprintf(frame_desc, sizeof(frame_desc), "ruby_frame_%d", frame_count);
+      VALUE name = rb_iseq_base_label(iseq);
+      const char *function_name = (name != Qnil) ? RSTRING_PTR(name) : "<unknown>";
 
-      // Try to get basic line info safely using direct struct access
+      VALUE filename = rb_iseq_path(iseq);
+      const char *file_name = (filename != Qnil) ? RSTRING_PTR(filename) : "<unknown>";
+
+      // Calculate line number using direct struct access
       int line_no = 0;
       if (iseq && cfp->pc) {
-        // Use direct access to iseq body instead of helper functions
         if (iseq->body && iseq->body->iseq_encoded && iseq->body->iseq_size > 0) {
           ptrdiff_t pc_offset = cfp->pc - iseq->body->iseq_encoded;
           if (pc_offset >= 0 && pc_offset < iseq->body->iseq_size) {
-            line_no = frame_count + 1; // Use frame position as approximation
+            // Use the Ruby VM line calculation like ddtrace_rb_profile_frames
+            size_t pos = pc_offset;
+            if (pos > 0) {
+              pos--; // Use pos-1 because PC points next instruction
+            }
+            line_no = rb_iseq_line_no(iseq, pos);
           }
         }
       }
 
       ddog_crasht_RuntimeStackFrame frame = {
-        .function_name = frame_desc,
-        .file_name = "ruby_source.rb",
+        .function_name = function_name,
+        .file_name = file_name,
         .line_number = line_no,
         .column_number = 0
       };
@@ -264,15 +260,6 @@ static void ruby_runtime_stack_callback(
       frame_count++;
     }
   }
-
-  // Emit end marker
-  ddog_crasht_RuntimeStackFrame end_frame = {
-    .function_name = "ruby_stack_walker_end",
-    .file_name = "crashtracker.c",
-    .line_number = frame_count,
-    .column_number = 0
-  };
-  emit_frame(&end_frame);
 }
 
 static VALUE _native_register_runtime_stack_callback(DDTRACE_UNUSED VALUE _self, VALUE callback_type) {

spec/datadog/core/crashtracking/component_spec.rb

@@ -240,7 +240,7 @@
             crash_tracker.start
             trigger.call
           end
-          puts(crash_report_experimental)
+          puts(crash_report_experimental.to_json)
           puts(log_messages)
           expect(stack_trace).to match(array_including(hash_including(function: function)))
           expect(stack_trace.size).to be > 10
@@ -348,7 +348,6 @@
       end
     end
 
-
     describe '#runtime_callback_registered?' do
       it 'returns true when callback is registered' do
         crashtracker = build_crashtracker(logger: logger)