Move service into VM

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/isolate_data.h"
-#include "bin/resources.h"
 #include "bin/thread.h"
 
-#include "vm/dart_api_impl.h"
-#include "vm/dart_entry.h"
-#include "vm/isolate.h"
-#include "vm/message.h"
-#include "vm/native_entry.h"
-#include "vm/native_arguments.h"
-#include "vm/object.h"
-#include "vm/port.h"
-#include "vm/snapshot.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* kVMServiceIOLibraryScriptResourceName =
-    kLibraryResourceNamePrefix "/vmservice_io.dart";
-static const char* kVMServiceLibraryName =
-    kLibraryResourceNamePrefix "/vmservice.dart";
-
+#define kLibrarySourceNamePrefix "/vmservice"
+static const char* kVMServiceIOLibraryScriptResourceName = "vmservice_io.dart";
 #define kClientResourceNamePrefix "/vmservice/client/deployed/web"
 
-Dart_Isolate VmService::isolate_ = NULL;
-Dart_Port VmService::port_ = ILLEGAL_PORT;
-dart::Monitor* VmService::monitor_ = NULL;
+struct ResourcesEntry {
+  const char* path_;
+  const char* resource_;
+  int length_;
+};
+
+extern ResourcesEntry __service_bin_resources_[];
+
+class Resources {
+ public:
+  static const int kNoSuchInstance = -1;
+  static int ResourceLookup(const char* path, const char** resource) {
+    ResourcesEntry* table = get_resources_table();
+    for (int i = 0; table[i].path_ != NULL; i++) {
+      const ResourcesEntry& entry = table[i];
+      if (strcmp(path, entry.path_) == 0) {
+        *resource = entry.resource_;
+        ASSERT(entry.length_ > 0);
+        return entry.length_;
+      }
+    }
+    return kNoSuchInstance;
+  }
+
+  static const char* get_resource_path(int idx) {

[siva, 2014/01/10 00:01:54]

These are not strictly accessors so you probably need to use camel case for the
name. How about just Path?

+    ASSERT(idx >= 0);
+    ResourcesEntry* entry = get_resource_entry(idx);
+    if (entry == NULL) {
+      return NULL;
+    }
+    return entry->path_;

[siva, 2014/01/10 00:01:54]

should we assert that entry_path_ is not NULL ?

+  }
+
+  static const char* get_resource_resource(int idx) {

[siva, 2014/01/10 00:01:54]

How about Resource for this.

[Cutch, 2014/01/10 21:01:42]

Killed it.

+    ASSERT(idx >= 0);
+    ResourcesEntry* entry = get_resource_entry(idx);
+    if (entry == NULL) {
+      return NULL;
+    }
+    return entry->resource_;
+  }
+
+ private:
+  static ResourcesEntry* get_resource_entry(int idx) {

[siva, 2014/01/10 00:01:54]

Ditto Entry?

[Cutch, 2014/01/10 21:01:42]

Renamed to "At".

+    ASSERT(idx >= 0);
+    ResourcesEntry* table = get_resources_table();
+    for (int i = 0; table[i].path_ != NULL; i++) {
+      if (idx == i) {
+        return &table[i];
+      }
+    }
+    return NULL;
+  }
+  static ResourcesEntry* get_resources_table() {

[siva, 2014/01/10 00:01:54]

service_bin_resources() or ResourcesTable for this ?

[Cutch, 2014/01/10 21:01:42]

Done.

+    return &__service_bin_resources_[0];
+  }
+
+  DISALLOW_ALLOCATION();
+  DISALLOW_IMPLICIT_CONSTRUCTORS(Resources);
+};
+
 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
-
-
-static Dart_NativeFunction VmServiceNativeResolver(Dart_Handle name,
-                                                   int num_arguments,
-                                                   bool* auto_setup_scope);
-
-
 bool VmService::Start(intptr_t server_port) {
-  monitor_ = new dart::Monitor();
-  ASSERT(monitor_ != NULL);
-  error_msg_ = NULL;
-
-
-  {
-    // Take lock before spawning new thread.
-    MonitorLocker ml(monitor_);
-    // Spawn new thread.
-    dart::Thread::Start(ThreadMain, server_port);
-    // Wait until service is running on spawned thread.
-    ml.Wait();
+  bool r = _Start(server_port);
+  if (!r) {
+    return r;
   }
-  return port_ != ILLEGAL_PORT;
+  // Start processing messages in a new thread.
+  dart::Thread::Start(ThreadMain, NULL);
+  return true;
 }
 
 
 bool VmService::_Start(intptr_t server_port) {
-  ASSERT(isolate_ == NULL);
-  char* error = NULL;
-  const char* script_uri = "vmservice:";
-  IsolateData* isolate_data = new IsolateData(script_uri);
-  isolate_ = Dart_CreateIsolate(script_uri, "main", snapshot_buffer,
-                                isolate_data,
-                                &error);
-  if (isolate_ == NULL) {
-    error_msg_ = error;
+  ASSERT(Dart_CurrentIsolate() == NULL);
+  Dart_Isolate isolate = Dart_GetServiceIsolate();

[siva, 2014/01/10 00:01:54]

As discussed offline it would be great if we just did
Dart_Handle service_port = Dart_GetServicePort();
here and then just sent messages to the port. Not have to deal with starting a
thread etc..

[Cutch, 2014/01/10 21:01:42]

Agree that I should follow this cleanup with another which further moves the
service into the VM and out of the embedder. 

+  if (isolate == NULL) {
+    error_msg_ = "Internal error.";
     return false;
   }
-
+  Dart_EnterIsolate(isolate);
   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(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(kVMServiceIOLibraryScriptResourceName);
-    SHUTDOWN_ON_ERROR(library);
-  }
-
-  // Make the isolate runnable so that it is ready to handle messages.
+  // Install our own library tag handler.
+  Dart_SetLibraryTagHandler(LibraryTagHandler);
+  Dart_Handle result;
+  Dart_Handle library = LoadScript(kVMServiceIOLibraryScriptResourceName);
+  // Expect a library.
+  ASSERT(library != Dart_Null());
+  SHUTDOWN_ON_ERROR(library);
   Dart_ExitScope();
   Dart_ExitIsolate();
-
-  bool retval = Dart_IsolateMakeRunnable(isolate_);
+  bool retval = Dart_IsolateMakeRunnable(isolate);
   if (!retval) {
-    Dart_EnterIsolate(isolate_);
+    Dart_EnterIsolate(isolate);
     Dart_ShutdownIsolate();
     error_msg_ = "Invalid isolate state - Unable to make it runnable.";
     return false;
   }
 
-  Dart_EnterIsolate(isolate_);
+  Dart_EnterIsolate(isolate);
   Dart_EnterScope();
-
-
-  Dart_Handle library = Dart_RootLibrary();
+  library = Dart_RootLibrary();
   // Set requested TCP port.
   DartUtils::SetIntegerField(library, "_port", server_port);
   result = Dart_Invoke(library, DartUtils::NewString("main"), 0, NULL);
   SHUTDOWN_ON_ERROR(result);
-
-  // Retrieve the ReceivePort that the service is waiting on. The _receivePort
-  // variable is setup in the call to main.
-  Dart_Handle receivePort = Dart_GetField(library,
-                                          DartUtils::NewString("_receivePort"));
-  SHUTDOWN_ON_ERROR(receivePort);
-
-  {
-    // Extract the Dart_Port from the receive port.
-    HANDLESCOPE(Isolate::Current());
-    const Object& unwrapped_rp = Object::Handle(Api::UnwrapHandle(receivePort));
-    const Instance& rp = Instance::Cast(unwrapped_rp);
-    // Extract ReceivePort port id.
-    const Object& rp_id_obj = Object::Handle(DartLibraryCalls::PortGetId(rp));
-    if (rp_id_obj.IsError()) {
-      const Error& error = Error::Cast(rp_id_obj);
-      error_msg_ = strdup(error.ToErrorCString());
-      Dart_ExitScope();
-      Dart_ShutdownIsolate();
-      return false;
-    }
-    ASSERT(rp_id_obj.IsSmi() || rp_id_obj.IsMint());
-    Integer& id = Integer::Handle();
-    id ^= rp_id_obj.raw();
-    port_ = static_cast<Dart_Port>(id.AsInt64Value());
-  }
-
-  Dart_Handle library_name = Dart_NewStringFromCString(kVMServiceLibraryName);
-  library = Dart_LookupLibrary(library_name);
-  SHUTDOWN_ON_ERROR(library);
+  // Load resources.
   result = LoadResources(library);
   SHUTDOWN_ON_ERROR(result);
 
   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::GetSource(const char* name) {
+  const intptr_t kBufferSize = 512;
+  char buffer[kBufferSize];
+  snprintf(&buffer[0], kBufferSize-1, "%s/%s", kLibrarySourceNamePrefix, name);
   const char* vmservice_source = NULL;
-  int r = Resources::ResourceLookup(name, &vmservice_source);
+  int r = Resources::ResourceLookup(buffer, &vmservice_source);
   ASSERT(r != Resources::kNoSuchInstance);
   return Dart_NewStringFromCString(vmservice_source);
 }
 
 
 Dart_Handle VmService::LoadScript(const char* name) {
-  Dart_Handle url = Dart_NewStringFromCString(name);
+  Dart_Handle url = Dart_NewStringFromCString("dart:vmservice_io");
   Dart_Handle source = GetSource(name);
   return Dart_LoadScript(url, source, 0, 0);
 }
 
 
 Dart_Handle VmService::LoadSource(Dart_Handle library, const char* name) {
   Dart_Handle url = Dart_NewStringFromCString(name);
   Dart_Handle source = GetSource(name);
   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);
@@ skipping 23 matching lines @@
   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++) {
+  for (intptr_t i = 0; Resources::get_resource_path(i) != NULL; 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;
 }
 
 
-static bool IsVMServiceURL(const char* url) {
-  static const intptr_t kLibraryResourceNamePrefixLen =
-      strlen(kLibraryResourceNamePrefix);
-  return 0 == strncmp(kLibraryResourceNamePrefix, url,
-                      kLibraryResourceNamePrefixLen);
-}
-
-
-static bool IsVMServiceLibrary(const char* url) {
-  return 0 == strcmp(kVMServiceLibraryName, url);
-}
-
-
 Dart_Handle VmService::LibraryTagHandler(Dart_LibraryTag tag,
                                          Dart_Handle library,
                                          Dart_Handle url) {
   if (!Dart_IsLibrary(library)) {
     return Dart_NewApiError("not a library");
   }
   if (!Dart_IsString(url)) {
     return Dart_NewApiError("url is not a string");
   }
   const char* url_string = NULL;
   Dart_Handle result = Dart_StringToCString(url, &url_string);
   if (Dart_IsError(result)) {
     return result;
   }
   Dart_Handle library_url = Dart_LibraryUrl(library);
   const char* library_url_string = NULL;
   result = Dart_StringToCString(library_url, &library_url_string);
   if (Dart_IsError(result)) {
     return result;
   }
-  bool is_vm_service_url = IsVMServiceURL(url_string);
-  if (!is_vm_service_url) {
-    // Pass to DartUtils.
+  if (tag == Dart_kImportTag) {
+    // Embedder handles all requests for external libraries.
     return DartUtils::LibraryTagHandler(tag, library, url);
   }
-  switch (tag) {
-    case Dart_kCanonicalizeUrl:
-      // The URL is already canonicalized.
-      return url;
-    break;
-    case Dart_kImportTag: {
-      Dart_Handle source = GetSource(url_string);
-      if (Dart_IsError(source)) {
-        return source;
-      }
-      Dart_Handle lib = Dart_LoadLibrary(url, source);
-      if (Dart_IsError(lib)) {
-        return lib;
-      }
-      if (IsVMServiceLibrary(url_string)) {
-        // Install native resolver for this library.
-        result = Dart_SetNativeResolver(lib, VmServiceNativeResolver);
-        if (Dart_IsError(result)) {
-          return result;
-        }
-      }
-      return lib;
-    }
-    break;
-    case Dart_kSourceTag: {
-      Dart_Handle source = GetSource(url_string);
-      if (Dart_IsError(source)) {
-        return source;
-      }
-      return Dart_LoadSource(library, url, source);
-    }
-    break;
-    default:
-      UNIMPLEMENTED();
-    break;
+  ASSERT((tag == Dart_kSourceTag) || (tag == Dart_kCanonicalizeUrl));
+  if (tag == Dart_kCanonicalizeUrl) {
+    // url is already canonicalized.
+    return url;
   }
-  UNREACHABLE();
-  return result;
+  Dart_Handle source = GetSource(url_string);
+  if (Dart_IsError(source)) {
+    return source;
+  }
+  return Dart_LoadSource(library, url, source);
 }
 
 
 void VmService::ThreadMain(uword parameters) {
   ASSERT(Dart_CurrentIsolate() == NULL);
-  ASSERT(isolate_ == NULL);
-
-  intptr_t server_port = static_cast<intptr_t>(parameters);
-  ASSERT(server_port >= 0);
-
-  // Lock scope.
-  {
-    MonitorLocker ml(monitor_);
-    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();
-  }
-
-  // Keep handling messages until the last active receive port is closed.
+  Dart_Isolate service_isolate = Dart_GetServiceIsolate();
+  Dart_EnterIsolate(service_isolate);
+  Dart_EnterScope();
   Dart_Handle result = Dart_RunLoop();
   if (Dart_IsError(result)) {
-    printf("VmService has exited with an error:\n%s\n", Dart_GetError(result));
+    printf("Service exited with an error:\n%s\n", Dart_GetError(result));
   }
-
-  _Stop();
-
   Dart_ExitScope();
   Dart_ExitIsolate();
 }
 
 
-static Dart_Handle MakeServiceControlMessage(Dart_Port port_id, intptr_t code,
-                                             Dart_Handle name) {
-  Dart_Handle result;
-  Dart_Handle list = Dart_NewList(4);
-  ASSERT(!Dart_IsError(list));
-  Dart_Handle code_handle = Dart_NewInteger(code);
-  ASSERT(!Dart_IsError(code_handle));
-  result = Dart_ListSetAt(list, 0, code_handle);
-  ASSERT(!Dart_IsError(result));
-  Dart_Handle port_id_handle = Dart_NewInteger(port_id);
-  ASSERT(!Dart_IsError(port_id_handle));
-  result = Dart_ListSetAt(list, 1, port_id_handle);
-  ASSERT(!Dart_IsError(result));
-  Dart_Handle sendPort = Dart_NewSendPort(port_id);
-  ASSERT(!Dart_IsError(sendPort));
-  result = Dart_ListSetAt(list, 2, sendPort);
-  ASSERT(!Dart_IsError(result));
-  result = Dart_ListSetAt(list, 3, name);
-  ASSERT(!Dart_IsError(result));
-  return list;
-}
-
-
-bool VmService::SendIsolateStartupMessage() {
-  if (!IsRunning()) {
-    return false;
-  }
-  Isolate* isolate = Isolate::Current();
-  ASSERT(isolate != NULL);
-  HANDLESCOPE(isolate);
-  Dart_Handle name = Api::NewHandle(isolate, String::New(isolate->name()));
-  ASSERT(!Dart_IsError(name));
-  Dart_Handle list =
-      MakeServiceControlMessage(Dart_GetMainPortId(),
-                                VM_SERVICE_ISOLATE_STARTUP_MESSAGE_ID,
-                                name);
-  ASSERT(!Dart_IsError(list));
-  return Dart_Post(port_, list);
-}
-
-
-bool VmService::SendIsolateShutdownMessage() {
-  if (!IsRunning()) {
-    return false;
-  }
-  Isolate* isolate = Isolate::Current();
-  ASSERT(isolate != NULL);
-  HANDLESCOPE(isolate);
-  Dart_Handle list =
-      MakeServiceControlMessage(Dart_GetMainPortId(),
-                                VM_SERVICE_ISOLATE_SHUTDOWN_MESSAGE_ID,
-                                Dart_Null());
-  ASSERT(!Dart_IsError(list));
-  return Dart_Post(port_, list);
-}
-
-
-void VmService::VmServiceShutdownCallback(void* callback_data) {
-  ASSERT(Dart_CurrentIsolate() != NULL);
-  Dart_EnterScope();
-  VmService::SendIsolateShutdownMessage();
-  Dart_ExitScope();
-}
-
-
-static uint8_t* allocator(uint8_t* ptr, intptr_t old_size, intptr_t new_size) {
-  void* new_ptr = realloc(reinterpret_cast<void*>(ptr), new_size);
-  return reinterpret_cast<uint8_t*>(new_ptr);
-}
-
-
-static void SendServiceMessage(Dart_NativeArguments args) {
-  NativeArguments* arguments = reinterpret_cast<NativeArguments*>(args);
-  Isolate* isolate = arguments->isolate();
-  StackZone zone(isolate);
-  HANDLESCOPE(isolate);
-  GET_NON_NULL_NATIVE_ARGUMENT(Instance, sp, arguments->NativeArgAt(0));
-  GET_NON_NULL_NATIVE_ARGUMENT(Instance, message, arguments->NativeArgAt(1));
-
-  // Extract SendPort port id.
-  const Object& sp_id_obj = Object::Handle(DartLibraryCalls::PortGetId(sp));
-  if (sp_id_obj.IsError()) {
-    Exceptions::PropagateError(Error::Cast(sp_id_obj));
-  }
-  Integer& id = Integer::Handle();
-  id ^= sp_id_obj.raw();
-  Dart_Port sp_id = static_cast<Dart_Port>(id.AsInt64Value());
-  ASSERT(sp_id != ILLEGAL_PORT);
-
-  // Serialize message.
-  uint8_t* data = NULL;
-  MessageWriter writer(&data, &allocator);
-  writer.WriteMessage(message);
-
-  // TODO(turnidge): Throw an exception when the return value is false?
-  PortMap::PostMessage(new Message(sp_id, data, writer.BytesWritten(),
-                                   Message::kOOBPriority));
-}
-
-
-struct VmServiceNativeEntry {
-  const char* name;
-  int num_arguments;
-  Dart_NativeFunction function;
-};
-
-
-static VmServiceNativeEntry _VmServiceNativeEntries[] = {
-  {"VMService_SendServiceMessage", 2, SendServiceMessage}
-};
-
-
-static Dart_NativeFunction VmServiceNativeResolver(Dart_Handle name,
-                                                   int num_arguments,
-                                                   bool* auto_setup_scope) {
-  const Object& obj = Object::Handle(Api::UnwrapHandle(name));
-  if (!obj.IsString()) {
-    return NULL;
-  }
-  const char* function_name = obj.ToCString();
-  ASSERT(function_name != NULL);
-  ASSERT(auto_setup_scope != NULL);
-  *auto_setup_scope = true;
-  intptr_t n =
-      sizeof(_VmServiceNativeEntries) / sizeof(_VmServiceNativeEntries[0]);
-  for (intptr_t i = 0; i < n; i++) {
-    VmServiceNativeEntry entry = _VmServiceNativeEntries[i];
-    if (!strcmp(function_name, entry.name) &&
-        (num_arguments == entry.num_arguments)) {
-      return entry.function;
-    }
-  }
-  return NULL;
-}
 
 }  // namespace bin
 }  // namespace dart