Initial NOOP VM Service

runtime/bin/vmservice_impl.cc

+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+#include "bin/vmservice_impl.h"
+
+#include "include/dart_api.h"
+
+#include "bin/builtin.h"
+#include "bin/dartutils.h"
+#include "bin/resources.h"
+#include "bin/thread.h"
+#include "bin/isolate_data.h"
+
+
+namespace dart {
+namespace bin {
+
+// snapshot_buffer points to a snapshot if we link in a snapshot otherwise
+// it is initialized to NULL.
+extern const uint8_t* snapshot_buffer;
+#define RETURN_ERROR_HANDLE(handle)                             \
+  if (Dart_IsError(handle)) {                                   \
+    return handle;                                              \
+  }
+
+#define SHUTDOWN_ON_ERROR(handle)                               \
+  if (Dart_IsError(handle)) {                                   \
+    error_msg_ = strdup(Dart_GetError(handle));                 \
+    Dart_ExitScope();                                           \
+    Dart_ShutdownIsolate();                                     \
+    return false;                                               \
+  }
+
+#define kLibraryResourceNamePrefix "/vmservice"
+static const char* kLibraryScriptResourceName =
+    kLibraryResourceNamePrefix "/vmservice.dart";
+static const char* kLibrarySourceResourceNames[] = {
+    NULL
+};
+
+#define kClientResourceNamePrefix "/client/web/out"
+
+Dart_Isolate VmService::isolate_ = NULL;
+Dart_Port VmService::port_ = ILLEGAL_PORT;
+dart::Monitor* VmService::monitor_ = NULL;
+const char* VmService::error_msg_ = NULL;
+
+// These must be kept in sync with vmservice/constants.dart
+#define VM_SERVICE_ISOLATE_STARTUP_MESSAGE_ID 1
+#define VM_SERVICE_ISOLATE_SHUTDOWN_MESSAGE_ID 2
+
+
+bool VmService::Start(intptr_t server_port) {
+  monitor_ = new dart::Monitor();
+  ASSERT(monitor_ != NULL);
+  error_msg_ = NULL;
+
+  // The VM service is initialized on a new thread.
+  dart::Thread::Start(ThreadMain, server_port);
+  {
+    // Wait until service is running.
+    MonitorLocker ml(monitor_);
+    ml.Wait();
+  }
+  return port_ != ILLEGAL_PORT;
+}
+
+
+bool VmService::_Start(intptr_t server_port) {
+  ASSERT(isolate_ == NULL);
+  char* error = NULL;
+  isolate_ = Dart_CreateIsolate("vmservice:", "main", snapshot_buffer,
+                                new IsolateData(),
+                                &error);
+  if (isolate_ == NULL) {
+    error_msg_ = error;
+    return false;
+  }
+
+  Dart_EnterScope();
+
+  if (snapshot_buffer != NULL) {
+    // Setup the native resolver as the snapshot does not carry it.
+    Builtin::SetNativeResolver(Builtin::kBuiltinLibrary);
+    Builtin::SetNativeResolver(Builtin::kIOLibrary);
+  }
+
+  // Set up the library tag handler for this isolate.
+  Dart_Handle result = Dart_SetLibraryTagHandler(DartUtils::LibraryTagHandler);
+  SHUTDOWN_ON_ERROR(result);
+
+  // Load the specified application script into the newly created isolate.
+
+  // Prepare builtin and its dependent libraries for use to resolve URIs.
+  // The builtin library is part of the core snapshot and would already be
+  // available here in the case of script snapshot loading.
+  Dart_Handle builtin_lib =
+      Builtin::LoadAndCheckLibrary(Builtin::kBuiltinLibrary);
+  SHUTDOWN_ON_ERROR(builtin_lib);
+
+  // Prepare for script loading by setting up the 'print' and 'timer'
+  // closures and setting up 'package root' for URI resolution.
+  result = DartUtils::PrepareForScriptLoading("", builtin_lib);
+  SHUTDOWN_ON_ERROR(result);
+
+  {
+    // Load source into service isolate.
+    Dart_Handle library = LoadScript(kLibraryScriptResourceName);
+    SHUTDOWN_ON_ERROR(library);
+    result = LoadSources(library, kLibrarySourceResourceNames);
+    SHUTDOWN_ON_ERROR(result);
+  }
+
+  // Make the isolate runnable so that it is ready to handle messages.
+  Dart_ExitScope();
+  Dart_ExitIsolate();
+
+  bool retval = Dart_IsolateMakeRunnable(isolate_);
+  if (!retval) {
+    Dart_EnterIsolate(isolate_);
+    Dart_ShutdownIsolate();
+    error_msg_ = "Invalid isolate state - Unable to make it runnable.";
+    return false;
+  }
+
+  Dart_EnterIsolate(isolate_);
+  Dart_EnterScope();
+
+  Dart_Handle library = Dart_RootLibrary();
+  result = Dart_Invoke(library, DartUtils::NewString("main"), 0, NULL);
+  SHUTDOWN_ON_ERROR(result);
+
+  result = LoadResources(library);
+  SHUTDOWN_ON_ERROR(result);
+
+  port_ = Dart_GetMainPortId();
+
+  Dart_ExitScope();
+  Dart_ExitIsolate();
+
+  return true;
+}
+
+
+void VmService::_Stop() {
+  port_ = ILLEGAL_PORT;
+}
+
+
+const char* VmService::GetErrorMessage() {
+  return error_msg_ == NULL ? "No error." : error_msg_;
+}
+
+
+Dart_Port VmService::port() {
+  return port_;
+}
+
+
+bool VmService::IsRunning() {
+  return port_ != ILLEGAL_PORT;
+}
+
+
+Dart_Handle VmService::LoadScript(const char* name) {
+  Dart_Handle url = Dart_NewStringFromCString(name);
+  const char* vmservice_source = NULL;
+  int r = Resources::ResourceLookup(name, &vmservice_source);
+  ASSERT(r != Resources::kNoSuchInstance);
+  Dart_Handle source = Dart_NewStringFromCString(vmservice_source);
+  return Dart_LoadScript(url, source, 0, 0);
+}
+
+
+Dart_Handle VmService::LoadSource(Dart_Handle library, const char* name) {
+  Dart_Handle url = Dart_NewStringFromCString(name);
+  const char* vmservice_source = NULL;
+  int r = Resources::ResourceLookup(name, &vmservice_source);
+  if (r == Resources::kNoSuchInstance) {
+    printf("Can't find %s\n", name);
+  }
+  ASSERT(r != Resources::kNoSuchInstance);
+  Dart_Handle source = Dart_NewStringFromCString(vmservice_source);
+  return Dart_LoadSource(library, url, source);
+}
+
+
+Dart_Handle VmService::LoadSources(Dart_Handle library, const char* names[]) {
+  Dart_Handle result = Dart_Null();
+  for (int i = 0; names[i] != NULL; i++) {
+    result = LoadSource(library, names[i]);
+    if (Dart_IsError(result)) {
+      break;
+    }
+  }
+  return result;
+}
+
+
+Dart_Handle VmService::LoadResource(Dart_Handle library,
+                                    const char* resource_name,
+                                    const char* prefix) {
+  intptr_t prefix_len = strlen(prefix);
+  // Prepare for invoke call.
+  Dart_Handle name = Dart_NewStringFromCString(resource_name+prefix_len);
+  RETURN_ERROR_HANDLE(name);
+  const char* data_buffer = NULL;
+  int data_buffer_length = Resources::ResourceLookup(resource_name,
+                                                     &data_buffer);
+  if (data_buffer_length == Resources::kNoSuchInstance) {
+    printf("Could not find %s %s\n", resource_name, resource_name+prefix_len);
+  }
+  ASSERT(data_buffer_length != Resources::kNoSuchInstance);
+  Dart_Handle data_list = Dart_NewTypedData(Dart_TypedData_kUint8,
+                                            data_buffer_length);
+  RETURN_ERROR_HANDLE(data_list);
+  Dart_TypedData_Type type = Dart_TypedData_kInvalid;
+  void* data_list_buffer = NULL;
+  intptr_t data_list_buffer_length = 0;
+  Dart_Handle result = Dart_TypedDataAcquireData(data_list, &type,
+                                                 &data_list_buffer,
+                                                 &data_list_buffer_length);
+  RETURN_ERROR_HANDLE(result);
+  ASSERT(data_buffer_length == data_list_buffer_length);
+  ASSERT(data_list_buffer != NULL);
+  ASSERT(type = Dart_TypedData_kUint8);
+  memmove(data_list_buffer, &data_buffer[0], data_buffer_length);
+  result = Dart_TypedDataReleaseData(data_list);
+  RETURN_ERROR_HANDLE(result);
+
+  // Make invoke call.
+  const intptr_t kNumArgs = 2;
+  Dart_Handle args[kNumArgs] = { name, data_list };
+  result = Dart_Invoke(library, Dart_NewStringFromCString("_addResource"),
+                       kNumArgs, args);
+  return result;
+}
+
+
+Dart_Handle VmService::LoadResources(Dart_Handle library) {
+  Dart_Handle result = Dart_Null();
+  intptr_t prefixLen = strlen(kClientResourceNamePrefix);
+  for (intptr_t i = 0; i < Resources::get_resource_count(); i++) {
+    const char* path = Resources::get_resource_path(i);
+    if (!strncmp(path, kClientResourceNamePrefix, prefixLen)) {
+      result = LoadResource(library, path, kClientResourceNamePrefix);
+      if (Dart_IsError(result)) {
+        break;
+      }
+    }
+  }
+  return result;
+}
+
+
+void VmService::ThreadMain(uword parameters) {
+  ASSERT(Dart_CurrentIsolate() == NULL);
+  ASSERT(isolate_ == NULL);

[siva, 2013/07/16 00:00:04]

I think you would have to close the MonitorLocker scope before
invoking Dart_Runloop as that guy blocks ans we don't want to be holding the
lock while blocking.

{

+  MonitorLocker ml(monitor_);
+  intptr_t server_port = static_cast<intptr_t>(parameters);
+  ASSERT(server_port >= 0);
+
+  bool r = _Start(server_port);
+  if (!r) {
+    port_ = ILLEGAL_PORT;
+    monitor_->Notify();
+    return;
+  }
+
+  Dart_EnterIsolate(isolate_);
+  Dart_EnterScope();
+
+  Dart_Handle receievePort = Dart_GetReceivePort(port_);
+  ASSERT(!Dart_IsError(receievePort));
+
+  monitor_->Notify();

[siva, 2013/07/16 00:00:04]

}

+  // Keep handling messages until the last active receive port is closed.
+  Dart_Handle result = Dart_RunLoop();
+  if (Dart_IsError(result)) {
+    printf("VmService error %s\n", Dart_GetError(result));
+  }
+
+  _Stop();
+
+  Dart_ExitScope();
+  Dart_ExitIsolate();
+}
+
+
+
+
+static Dart_Handle MakeServiceControlMessage(Dart_Port port) {
+  Dart_Handle list = Dart_NewList(2);
+  ASSERT(!Dart_IsError(list));
+  Dart_Handle sendPort = Dart_NewSendPort(port);
+  ASSERT(!Dart_IsError(sendPort));
+  Dart_ListSetAt(list, 1, sendPort);
+  return list;
+}
+
+
+bool VmService::SendIsolateStartupMessage(Dart_Port port) {
+  if (!IsRunning()) {
+    return false;
+  }
+  Dart_Isolate isolate = Dart_CurrentIsolate();
+  ASSERT(isolate != NULL);
+  ASSERT(Dart_GetMainPortId() == port);
+  Dart_Handle list = MakeServiceControlMessage(port);
+  Dart_ListSetAt(list, 0,
+                 Dart_NewInteger(VM_SERVICE_ISOLATE_STARTUP_MESSAGE_ID));
+  return Dart_Post(port_, list);
+}
+
+
+bool VmService::SendIsolateShutdownMessage(Dart_Port port) {
+  if (!IsRunning()) {
+    return false;
+  }
+  Dart_Isolate isolate = Dart_CurrentIsolate();
+  ASSERT(isolate != NULL);
+  ASSERT(Dart_GetMainPortId() == port);
+  Dart_Handle list = MakeServiceControlMessage(port);
+  Dart_ListSetAt(list, 0,
+                 Dart_NewInteger(VM_SERVICE_ISOLATE_SHUTDOWN_MESSAGE_ID));
+  return Dart_Post(port_, list);
+}
+
+
+}  // namespace bin
+}  // namespace dart