Module: MilkTea::DAP::Server::ServerLLDBBackend

Included in:
MilkTea::DAP::Server
Defined in:
lib/milk_tea/dap/server/lldb_backend.rb

Instance Method Summary collapse

Instance Method Details

#backend_configuration_pending? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 251

def backend_configuration_pending?
  backend_start_pending? && !backend_configuration_ready?
end

#backend_configuration_ready? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 242

def backend_configuration_ready?
  @backend_configuration_mutex.synchronize { @backend_configuration_ready }
end

#backend_continue_arguments ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 316

def backend_continue_arguments
  thread_id = @backend_stopped_thread_id || backend_thread_id_for_auto_continue
  return {} unless thread_id

  { "threadId" => thread_id }
end

#backend_error_message(backend_response) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 114

def backend_error_message(backend_response)
  message = backend_response["message"].to_s
  return message unless message.empty?

  error_body = backend_response.dig("body", "error")
  if error_body.is_a?(Hash)
    format = error_body["format"].to_s
    return format unless format.empty?

    error_message = error_body["message"].to_s
    return error_message unless error_message.empty?
  end

  "backend request failed"
end

#backend_initialize_arguments(client_arguments) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 298

def backend_initialize_arguments(client_arguments)
  {
    "adapterID" => "milk-tea",
    "clientID" => "milk-tea",
    "linesStartAt1" => true,
    "columnsStartAt1" => true,
    "pathFormat" => "path"
  }.merge(client_arguments)
end

#backend_request(command, arguments) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 60

def backend_request(command, arguments)
  unless @lldb_backend
    return {
      "success" => false,
      "message" => "lldb-dap backend is not running"
    }
  end

  @lldb_backend.request(command, arguments)
end

#backend_start_pending? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 246

def backend_start_pending?
  thread = @backend_start_thread
  thread && thread.alive?
end

#backend_supports_set_expression? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 367

def backend_supports_set_expression?
  capability_enabled?("supportsSetExpression")
end

#backend_supports_set_variable? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 363

def backend_supports_set_variable?
  capability_enabled?("supportsSetVariable")
end

#backend_terminate_unsupported?(backend_response) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 130

def backend_terminate_unsupported?(backend_response)
  message = backend_error_message(backend_response).downcase
  message.include?("unknown request") || message.include?("unsupported command")
end

#backend_thread_id_for_auto_continue ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 285

def backend_thread_id_for_auto_continue
  response = backend_request("threads", {})
  return nil unless response["success"]

  threads = response.dig("body", "threads")
  return nil unless threads.is_a?(Array)

  first_thread = threads.first
  return nil unless first_thread.is_a?(Hash)

  first_thread["id"]
end

#build_backend_request_response(request, client_response) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 229

def build_backend_request_response(request, client_response)
  response = {
    "seq" => @session.next_seq,
    "type" => "response",
    "request_seq" => request["seq"],
    "success" => !!client_response["success"],
    "command" => request["command"]
  }
  response["body"] = client_response["body"] if client_response.key?("body")
  response["message"] = client_response["message"] if client_response["message"]
  response
end

#build_backend_via_factory(adapter_command) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 135

def build_backend_via_factory(adapter_command)
  arity = @backend_factory.arity
  if arity < 0 || arity >= 3
    @backend_factory.call(adapter_command, method(:handle_backend_event), method(:handle_backend_request))
  else
    @backend_factory.call(adapter_command, method(:handle_backend_event))
  end
end

#capability_enabled?(name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 371

def capability_enabled?(name)
  value = @backend_capabilities[name] || @backend_capabilities[name.to_sym]
  !!value
end

#continued_event_signature(body) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 323

def continued_event_signature(body)
  return nil unless body.is_a?(Hash)

  [
    normalize_reference_key(dap_value(body, "threadId")),
    dap_value(body, "allThreadsContinued") == true,
  ]
end

#effective_adapter_capabilities ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 349

def effective_adapter_capabilities
  capabilities = ADAPTER_CAPABILITIES.merge(
    @backend_capabilities.transform_keys { |key| key.to_sym }
  )
  capabilities[:supportsSetVariable] = true if backend_supports_set_variable? || backend_supports_set_expression?

  backend_filters = @backend_capabilities["exceptionBreakpointFilters"]
  if backend_filters.is_a?(Array) && !backend_filters.empty?
    capabilities[:exceptionBreakpointFilters] = backend_filters
  end

  capabilities
end

#ensure_backend_initialized(client_arguments) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 49

def ensure_backend_initialized(client_arguments)
  return { "success" => true, "body" => @backend_capabilities } if @backend_initialized

  response = backend_request("initialize", backend_initialize_arguments(client_arguments))
  if response["success"]
    @backend_initialized = true
    @backend_capabilities = response["body"] || {}
  end
  response
end

#filter_breakpoint_for_backend(breakpoint) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 308

def filter_breakpoint_for_backend(breakpoint)
  breakpoint.each_with_object({}) do |(key, value), result|
    next if key.to_s == "id" || key.to_s == "verified"

    result[key.to_s] = value
  end
end

#handle_backend_event(message) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 144

def handle_backend_event(message)
  event = message["event"].to_s
  body = message["body"]

  # The outer Milk Tea adapter owns the initialize/initialized handshake.
  # Forwarding lldb-dap's own initialized event causes VS Code to repeat
  # the configuration phase and emit a second configurationDone.
  if event == "initialized"
    mark_backend_configuration_ready
    return
  end

  if event == "stopped"
    pause_requested = @backend_pause_requested
    body = rewrite_backend_stopped_event_body(body)
    emit_pause_diagnostic_async(body) if pause_requested
    @backend_stopped_thread_id = body && body["threadId"]
    @backend_pause_requested = false
    @last_forwarded_continued_signature = nil
  elsif event == "continued"
    signature = continued_event_signature(body)
    return if signature && signature == @last_forwarded_continued_signature

    @backend_stopped_thread_id = nil
    @backend_pause_requested = false
    @last_forwarded_continued_signature = signature
  elsif event == "terminated" || event == "exited"
    @backend_stopped_thread_id = nil
    @backend_pause_requested = false
    @last_forwarded_continued_signature = nil
  end

  write_event(event, body)

  return unless event == "terminated" || event == "exited"

  @session.terminate!
end

#handle_backend_request(message) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 183

def handle_backend_request(message)
  client_seq = @session.next_seq
  queue = Queue.new
  @client_request_mutex.synchronize do
    @pending_client_responses[client_seq] = queue
  end

  write_message({
    seq: client_seq,
    type: "request",
    command: message["command"],
    arguments: message["arguments"] || {}
  })

  timeout_seconds = reverse_request_timeout
  client_response = Timeout.timeout(timeout_seconds) { queue.pop }
  build_backend_request_response(message, client_response)
rescue Timeout::Error
  {
    "seq" => @session.next_seq,
    "type" => "response",
    "request_seq" => message["seq"],
    "success" => false,
    "command" => message["command"],
    "message" => format("client request timed out after %.1fs: %s", timeout_seconds, message["command"])
  }
ensure
  @client_request_mutex.synchronize do
    @pending_client_responses.delete(client_seq) if defined?(client_seq)
  end
end

#handle_client_response(message) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 222

def handle_client_response(message)
  queue = @client_request_mutex.synchronize do
    @pending_client_responses[message["request_seq"]]
  end
  queue&.push(message)
end

#mark_backend_configuration_ready ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 272

def mark_backend_configuration_ready
  @backend_configuration_mutex.synchronize do
    @backend_configuration_ready = true
    @backend_configuration_condition.broadcast
  end
end

#request_backend_terminate(arguments) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 71

def request_backend_terminate(arguments)
  join_background_threads
  terminate_response = backend_request("terminate", arguments)
  return terminate_response if terminate_response["success"]
  return terminate_response unless backend_terminate_unsupported?(terminate_response)

  disconnect_response = backend_request("disconnect", arguments)
  return disconnect_response unless disconnect_response["success"]

  stop_lldb_backend
  cleanup_tmp_dirs
  unless @session.terminated?
    @session.terminate!
    write_event("terminated")
  end
  @session.request_exit!
  disconnect_response
end

#reset_backend_configuration_ready ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 279

def reset_backend_configuration_ready
  @backend_configuration_mutex.synchronize do
    @backend_configuration_ready = false
  end
end

#reverse_request_timeout ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 215

def reverse_request_timeout
  timeout = @reverse_request_timeout.to_f
  timeout.positive? ? timeout : 15.0
rescue StandardError
  15.0
end

#rewrite_backend_stopped_event_body(body) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 332

def rewrite_backend_stopped_event_body(body)
  return body unless @backend_pause_requested
  return body unless body.is_a?(Hash)

  reason = dap_value(body, "reason").to_s
  description = dap_value(body, "description").to_s
  text = dap_value(body, "text").to_s
  return body unless reason == "exception"
  return body unless description.match?(/\bSIGSTOP\b/) || text.match?(/\bSIGSTOP\b/)

  rewritten = body.dup
  dap_set(rewritten, "reason", "pause")
  dap_set(rewritten, "description", "Paused") if !description.empty? || rewritten.key?("description") || rewritten.key?(:description)
  dap_set(rewritten, "text", "Paused") if !text.empty? || rewritten.key?("text") || rewritten.key?(:text)
  rewritten
end

#start_backend_start_request(request, arguments) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 90

def start_backend_start_request(request, arguments)
  @backend_start_thread = Thread.new do
    Thread.current.report_on_exception = false if Thread.current.respond_to?(:report_on_exception=)

    backend_response = backend_request(request["command"], arguments)
    write_backend_response(request, backend_response)
  rescue StandardError => e
    write_error_response(request, "Internal error: #{e.message}")
  ensure
    @backend_start_thread = nil
    @backend_configuration_mutex.synchronize do
      @backend_configuration_condition.broadcast
    end
  end
end

#start_lldb_backend(args) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 11

def start_lldb_backend(args)
  return if @lldb_backend

  adapter_path = args["adapterPath"].to_s
  adapter_command = if adapter_path.empty?
                       @default_adapter_command || ["lldb-dap"]
                     else
                       expanded = File.expand_path(adapter_path)
                       expanded.end_with?(".rb") ? [RbConfig.ruby, expanded] : [expanded]
                     end

  @lldb_backend = if @backend_factory
    build_backend_via_factory(adapter_command)
  else
    Backends::LLDBDAP.new(
      adapter_command: adapter_command,
      on_event: method(:handle_backend_event),
      on_request: method(:handle_backend_request)
    )
  end
  @lldb_backend.start!
end

#stop_lldb_backend ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 34

def stop_lldb_backend
  @backend_start_thread&.join(0.2)
  @backend_start_thread = nil
  @backend_auto_continue_after_configuration = false
  @backend_stopped_thread_id = nil
  @backend_pause_requested = false
  @lldb_backend&.stop!
ensure
  @lldb_backend = nil
  @backend_initialized = false
  @backend_capabilities = {}
  reset_backend_configuration_ready
  clear_debug_context
end

#using_lldb_backend? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 7

def using_lldb_backend?
  @session.backend_kind == "lldb-dap"
end

#wait_for_backend_configuration_ready(timeout: 30) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 255

def wait_for_backend_configuration_ready(timeout: 30)
  return true unless backend_configuration_pending?

  deadline = Process.clock_gettime(Process::CLOCK_MONOTONIC) + timeout

  @backend_configuration_mutex.synchronize do
    while @backend_start_thread&.alive? && !@backend_configuration_ready
      remaining = deadline - Process.clock_gettime(Process::CLOCK_MONOTONIC)
      return false if remaining <= 0

      @backend_configuration_condition.wait(@backend_configuration_mutex, remaining)
    end
  end

  true
end

#write_backend_response(request, backend_response) ⇒ Object 



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# File 'lib/milk_tea/dap/server/lldb_backend.rb', line 106

def write_backend_response(request, backend_response)
  if backend_response["success"]
    write_response(request, backend_response["body"] || {})
  else
    write_error_response(request, backend_error_message(backend_response))
  end
end