[inspector] Initial import of v8_inspector.

src/inspector/V8HeapProfilerAgentImpl.cpp

+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/inspector/V8HeapProfilerAgentImpl.h"
+
+#include "src/inspector/InjectedScript.h"
+#include "src/inspector/StringUtil.h"
+#include "src/inspector/V8Debugger.h"
+#include "src/inspector/V8InspectorImpl.h"
+#include "src/inspector/V8InspectorSessionImpl.h"
+#include "src/inspector/protocol/Protocol.h"
+#include "src/inspector/public/V8InspectorClient.h"
+
+#include <v8-profiler.h>
+#include <v8-version.h>
+
+namespace v8_inspector {
+
+namespace {
+
+namespace HeapProfilerAgentState {
+static const char heapProfilerEnabled[] = "heapProfilerEnabled";
+static const char heapObjectsTrackingEnabled[] = "heapObjectsTrackingEnabled";
+static const char allocationTrackingEnabled[] = "allocationTrackingEnabled";
+#if V8_MAJOR_VERSION >= 5
+static const char samplingHeapProfilerEnabled[] = "samplingHeapProfilerEnabled";
+static const char samplingHeapProfilerInterval[] =
+    "samplingHeapProfilerInterval";
+#endif
+}
+
+class HeapSnapshotProgress final : public v8::ActivityControl {
+ public:
+  HeapSnapshotProgress(protocol::HeapProfiler::Frontend* frontend)
+      : m_frontend(frontend) {}
+  ControlOption ReportProgressValue(int done, int total) override {
+    m_frontend->reportHeapSnapshotProgress(done, total,
+                                           protocol::Maybe<bool>());
+    if (done >= total) {
+      m_frontend->reportHeapSnapshotProgress(total, total, true);
+    }
+    m_frontend->flush();
+    return kContinue;
+  }
+
+ private:
+  protocol::HeapProfiler::Frontend* m_frontend;
+};
+
+class GlobalObjectNameResolver final
+    : public v8::HeapProfiler::ObjectNameResolver {
+ public:
+  explicit GlobalObjectNameResolver(V8InspectorSessionImpl* session)
+      : m_offset(0), m_strings(10000), m_session(session) {}
+
+  const char* GetName(v8::Local<v8::Object> object) override {
+    InspectedContext* context = m_session->inspector()->getContext(
+        m_session->contextGroupId(),
+        V8Debugger::contextId(object->CreationContext()));
+    if (!context) return "";
+    String16 name = context->origin();
+    size_t length = name.length();
+    if (m_offset + length + 1 >= m_strings.size()) return "";
+    for (size_t i = 0; i < length; ++i) {
+      UChar ch = name[i];
+      m_strings[m_offset + i] = ch > 0xff ? '?' : static_cast<char>(ch);
+    }
+    m_strings[m_offset + length] = '\0';
+    char* result = &*m_strings.begin() + m_offset;
+    m_offset += length + 1;
+    return result;
+  }
+
+ private:
+  size_t m_offset;
+  std::vector<char> m_strings;
+  V8InspectorSessionImpl* m_session;
+};
+
+class HeapSnapshotOutputStream final : public v8::OutputStream {
+ public:
+  HeapSnapshotOutputStream(protocol::HeapProfiler::Frontend* frontend)
+      : m_frontend(frontend) {}
+  void EndOfStream() override {}
+  int GetChunkSize() override { return 102400; }
+  WriteResult WriteAsciiChunk(char* data, int size) override {
+    m_frontend->addHeapSnapshotChunk(String16(data, size));
+    m_frontend->flush();
+    return kContinue;
+  }
+
+ private:
+  protocol::HeapProfiler::Frontend* m_frontend;
+};
+
+v8::Local<v8::Object> objectByHeapObjectId(v8::Isolate* isolate, int id) {
+  v8::HeapProfiler* profiler = isolate->GetHeapProfiler();
+  v8::Local<v8::Value> value = profiler->FindObjectById(id);
+  if (value.IsEmpty() || !value->IsObject()) return v8::Local<v8::Object>();
+  return value.As<v8::Object>();
+}
+
+class InspectableHeapObject final : public V8InspectorSession::Inspectable {
+ public:
+  explicit InspectableHeapObject(int heapObjectId)
+      : m_heapObjectId(heapObjectId) {}
+  v8::Local<v8::Value> get(v8::Local<v8::Context> context) override {
+    return objectByHeapObjectId(context->GetIsolate(), m_heapObjectId);
+  }
+
+ private:
+  int m_heapObjectId;
+};
+
+class HeapStatsStream final : public v8::OutputStream {
+ public:
+  HeapStatsStream(protocol::HeapProfiler::Frontend* frontend)
+      : m_frontend(frontend) {}
+
+  void EndOfStream() override {}
+
+  WriteResult WriteAsciiChunk(char* data, int size) override {
+    DCHECK(false);
+    return kAbort;
+  }
+
+  WriteResult WriteHeapStatsChunk(v8::HeapStatsUpdate* updateData,
+                                  int count) override {
+    DCHECK_GT(count, 0);
+    std::unique_ptr<protocol::Array<int>> statsDiff =
+        protocol::Array<int>::create();
+    for (int i = 0; i < count; ++i) {
+      statsDiff->addItem(updateData[i].index);
+      statsDiff->addItem(updateData[i].count);
+      statsDiff->addItem(updateData[i].size);
+    }
+    m_frontend->heapStatsUpdate(std::move(statsDiff));
+    return kContinue;
+  }
+
+ private:
+  protocol::HeapProfiler::Frontend* m_frontend;
+};
+
+}  // namespace
+
+V8HeapProfilerAgentImpl::V8HeapProfilerAgentImpl(
+    V8InspectorSessionImpl* session, protocol::FrontendChannel* frontendChannel,
+    protocol::DictionaryValue* state)
+    : m_session(session),
+      m_isolate(session->inspector()->isolate()),
+      m_frontend(frontendChannel),
+      m_state(state),
+      m_hasTimer(false) {}
+
+V8HeapProfilerAgentImpl::~V8HeapProfilerAgentImpl() {}
+
+void V8HeapProfilerAgentImpl::restore() {
+  if (m_state->booleanProperty(HeapProfilerAgentState::heapProfilerEnabled,
+                               false))
+    m_frontend.resetProfiles();
+  if (m_state->booleanProperty(
+          HeapProfilerAgentState::heapObjectsTrackingEnabled, false))
+    startTrackingHeapObjectsInternal(m_state->booleanProperty(
+        HeapProfilerAgentState::allocationTrackingEnabled, false));
+#if V8_MAJOR_VERSION >= 5
+  if (m_state->booleanProperty(
+          HeapProfilerAgentState::samplingHeapProfilerEnabled, false)) {
+    ErrorString error;
+    double samplingInterval = m_state->doubleProperty(
+        HeapProfilerAgentState::samplingHeapProfilerInterval, -1);
+    DCHECK_GE(samplingInterval, 0);
+    startSampling(&error, Maybe<double>(samplingInterval));
+  }
+#endif
+}
+
+void V8HeapProfilerAgentImpl::collectGarbage(ErrorString*) {
+  m_isolate->LowMemoryNotification();
+}
+
+void V8HeapProfilerAgentImpl::startTrackingHeapObjects(
+    ErrorString*, const protocol::Maybe<bool>& trackAllocations) {
+  m_state->setBoolean(HeapProfilerAgentState::heapObjectsTrackingEnabled, true);
+  bool allocationTrackingEnabled = trackAllocations.fromMaybe(false);
+  m_state->setBoolean(HeapProfilerAgentState::allocationTrackingEnabled,
+                      allocationTrackingEnabled);
+  startTrackingHeapObjectsInternal(allocationTrackingEnabled);
+}
+
+void V8HeapProfilerAgentImpl::stopTrackingHeapObjects(
+    ErrorString* error, const protocol::Maybe<bool>& reportProgress) {
+  requestHeapStatsUpdate();
+  takeHeapSnapshot(error, reportProgress);
+  stopTrackingHeapObjectsInternal();
+}
+
+void V8HeapProfilerAgentImpl::enable(ErrorString*) {
+  m_state->setBoolean(HeapProfilerAgentState::heapProfilerEnabled, true);
+}
+
+void V8HeapProfilerAgentImpl::disable(ErrorString* error) {
+  stopTrackingHeapObjectsInternal();
+#if V8_MAJOR_VERSION >= 5
+  if (m_state->booleanProperty(
+          HeapProfilerAgentState::samplingHeapProfilerEnabled, false)) {
+    v8::HeapProfiler* profiler = m_isolate->GetHeapProfiler();
+    if (profiler) profiler->StopSamplingHeapProfiler();
+  }
+#endif
+  m_isolate->GetHeapProfiler()->ClearObjectIds();
+  m_state->setBoolean(HeapProfilerAgentState::heapProfilerEnabled, false);
+}
+
+void V8HeapProfilerAgentImpl::takeHeapSnapshot(
+    ErrorString* errorString, const protocol::Maybe<bool>& reportProgress) {
+  v8::HeapProfiler* profiler = m_isolate->GetHeapProfiler();
+  if (!profiler) {
+    *errorString = "Cannot access v8 heap profiler";
+    return;
+  }
+  std::unique_ptr<HeapSnapshotProgress> progress;
+  if (reportProgress.fromMaybe(false))
+    progress = wrapUnique(new HeapSnapshotProgress(&m_frontend));
+
+  GlobalObjectNameResolver resolver(m_session);
+  const v8::HeapSnapshot* snapshot =
+      profiler->TakeHeapSnapshot(progress.get(), &resolver);
+  if (!snapshot) {
+    *errorString = "Failed to take heap snapshot";
+    return;
+  }
+  HeapSnapshotOutputStream stream(&m_frontend);
+  snapshot->Serialize(&stream);
+  const_cast<v8::HeapSnapshot*>(snapshot)->Delete();
+}
+
+void V8HeapProfilerAgentImpl::getObjectByHeapObjectId(
+    ErrorString* error, const String16& heapSnapshotObjectId,
+    const protocol::Maybe<String16>& objectGroup,
+    std::unique_ptr<protocol::Runtime::RemoteObject>* result) {
+  bool ok;
+  int id = heapSnapshotObjectId.toInteger(&ok);
+  if (!ok) {
+    *error = "Invalid heap snapshot object id";
+    return;
+  }
+
+  v8::HandleScope handles(m_isolate);
+  v8::Local<v8::Object> heapObject = objectByHeapObjectId(m_isolate, id);
+  if (heapObject.IsEmpty()) {
+    *error = "Object is not available";
+    return;
+  }
+
+  if (!m_session->inspector()->client()->isInspectableHeapObject(heapObject)) {
+    *error = "Object is not available";
+    return;
+  }
+
+  *result = m_session->wrapObject(heapObject->CreationContext(), heapObject,
+                                  objectGroup.fromMaybe(""), false);
+  if (!result) *error = "Object is not available";
+}
+
+void V8HeapProfilerAgentImpl::addInspectedHeapObject(
+    ErrorString* errorString, const String16& inspectedHeapObjectId) {
+  bool ok;
+  int id = inspectedHeapObjectId.toInteger(&ok);
+  if (!ok) {
+    *errorString = "Invalid heap snapshot object id";
+    return;
+  }
+
+  v8::HandleScope handles(m_isolate);
+  v8::Local<v8::Object> heapObject = objectByHeapObjectId(m_isolate, id);
+  if (heapObject.IsEmpty()) {
+    *errorString = "Object is not available";
+    return;
+  }
+
+  if (!m_session->inspector()->client()->isInspectableHeapObject(heapObject)) {
+    *errorString = "Object is not available";
+    return;
+  }
+
+  m_session->addInspectedObject(wrapUnique(new InspectableHeapObject(id)));
+}
+
+void V8HeapProfilerAgentImpl::getHeapObjectId(ErrorString* errorString,
+                                              const String16& objectId,
+                                              String16* heapSnapshotObjectId) {
+  v8::HandleScope handles(m_isolate);
+  v8::Local<v8::Value> value;
+  v8::Local<v8::Context> context;
+  if (!m_session->unwrapObject(errorString, objectId, &value, &context,
+                               nullptr) ||
+      value->IsUndefined())
+    return;
+
+  v8::SnapshotObjectId id = m_isolate->GetHeapProfiler()->GetObjectId(value);
+  *heapSnapshotObjectId = String16::fromInteger(id);
+}
+
+void V8HeapProfilerAgentImpl::requestHeapStatsUpdate() {
+  HeapStatsStream stream(&m_frontend);
+  v8::SnapshotObjectId lastSeenObjectId =
+      m_isolate->GetHeapProfiler()->GetHeapStats(&stream);
+  m_frontend.lastSeenObjectId(
+      lastSeenObjectId, m_session->inspector()->client()->currentTimeMS());
+}
+
+// static
+void V8HeapProfilerAgentImpl::onTimer(void* data) {
+  reinterpret_cast<V8HeapProfilerAgentImpl*>(data)->requestHeapStatsUpdate();
+}
+
+void V8HeapProfilerAgentImpl::startTrackingHeapObjectsInternal(
+    bool trackAllocations) {
+  m_isolate->GetHeapProfiler()->StartTrackingHeapObjects(trackAllocations);
+  if (!m_hasTimer) {
+    m_hasTimer = true;
+    m_session->inspector()->client()->startRepeatingTimer(
+        0.05, &V8HeapProfilerAgentImpl::onTimer, reinterpret_cast<void*>(this));
+  }
+}
+
+void V8HeapProfilerAgentImpl::stopTrackingHeapObjectsInternal() {
+  if (m_hasTimer) {
+    m_session->inspector()->client()->cancelTimer(
+        reinterpret_cast<void*>(this));
+    m_hasTimer = false;
+  }
+  m_isolate->GetHeapProfiler()->StopTrackingHeapObjects();
+  m_state->setBoolean(HeapProfilerAgentState::heapObjectsTrackingEnabled,
+                      false);
+  m_state->setBoolean(HeapProfilerAgentState::allocationTrackingEnabled, false);
+}
+
+void V8HeapProfilerAgentImpl::startSampling(
+    ErrorString* errorString, const Maybe<double>& samplingInterval) {
+#if V8_MAJOR_VERSION >= 5
+  v8::HeapProfiler* profiler = m_isolate->GetHeapProfiler();
+  if (!profiler) {
+    *errorString = "Cannot access v8 heap profiler";
+    return;
+  }
+  const unsigned defaultSamplingInterval = 1 << 15;
+  double samplingIntervalValue =
+      samplingInterval.fromMaybe(defaultSamplingInterval);
+  m_state->setDouble(HeapProfilerAgentState::samplingHeapProfilerInterval,
+                     samplingIntervalValue);
+  m_state->setBoolean(HeapProfilerAgentState::samplingHeapProfilerEnabled,
+                      true);
+#if V8_MAJOR_VERSION * 1000 + V8_MINOR_VERSION >= 5002
+  profiler->StartSamplingHeapProfiler(
+      static_cast<uint64_t>(samplingIntervalValue), 128,
+      v8::HeapProfiler::kSamplingForceGC);
+#else
+  profiler->StartSamplingHeapProfiler(
+      static_cast<uint64_t>(samplingIntervalValue), 128);
+#endif
+#endif
+}
+
+#if V8_MAJOR_VERSION >= 5
+namespace {
+std::unique_ptr<protocol::HeapProfiler::SamplingHeapProfileNode>
+buildSampingHeapProfileNode(const v8::AllocationProfile::Node* node) {
+  auto children = protocol::Array<
+      protocol::HeapProfiler::SamplingHeapProfileNode>::create();
+  for (const auto* child : node->children)
+    children->addItem(buildSampingHeapProfileNode(child));
+  size_t selfSize = 0;
+  for (const auto& allocation : node->allocations)
+    selfSize += allocation.size * allocation.count;
+  std::unique_ptr<protocol::Runtime::CallFrame> callFrame =
+      protocol::Runtime::CallFrame::create()
+          .setFunctionName(toProtocolString(node->name))
+          .setScriptId(String16::fromInteger(node->script_id))
+          .setUrl(toProtocolString(node->script_name))
+          .setLineNumber(node->line_number - 1)
+          .setColumnNumber(node->column_number - 1)
+          .build();
+  std::unique_ptr<protocol::HeapProfiler::SamplingHeapProfileNode> result =
+      protocol::HeapProfiler::SamplingHeapProfileNode::create()
+          .setCallFrame(std::move(callFrame))
+          .setSelfSize(selfSize)
+          .setChildren(std::move(children))
+          .build();
+  return result;
+}
+}  // namespace
+#endif
+
+void V8HeapProfilerAgentImpl::stopSampling(
+    ErrorString* errorString,
+    std::unique_ptr<protocol::HeapProfiler::SamplingHeapProfile>* profile) {
+#if V8_MAJOR_VERSION >= 5
+  v8::HeapProfiler* profiler = m_isolate->GetHeapProfiler();
+  if (!profiler) {
+    *errorString = "Cannot access v8 heap profiler";
+    return;
+  }
+  v8::HandleScope scope(
+      m_isolate);  // Allocation profile contains Local handles.
+  std::unique_ptr<v8::AllocationProfile> v8Profile(
+      profiler->GetAllocationProfile());
+  profiler->StopSamplingHeapProfiler();
+  m_state->setBoolean(HeapProfilerAgentState::samplingHeapProfilerEnabled,
+                      false);
+  if (!v8Profile) {
+    *errorString = "Cannot access v8 sampled heap profile.";
+    return;
+  }
+  v8::AllocationProfile::Node* root = v8Profile->GetRootNode();
+  *profile = protocol::HeapProfiler::SamplingHeapProfile::create()
+                 .setHead(buildSampingHeapProfileNode(root))
+                 .build();
+#endif
+}
+
+}  // namespace v8_inspector