Reclassify heapsnapshot and nsJSInspector as not part of devtools

This resolves Issue #316

1 files changed, 224 insertions, 0 deletions

diff --git a/dom/heapsnapshot/HeapSnapshot.h b/dom/heapsnapshot/HeapSnapshot.h
new file mode 100644
index 000000000..12dfa4c2b
--- /dev/null
+++ b/dom/heapsnapshot/HeapSnapshot.h
@@ -0,0 +1,224 @@
+/* -*-  Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_devtools_HeapSnapshot__
+#define mozilla_devtools_HeapSnapshot__
+
+#include "js/HashTable.h"
+#include "mozilla/ErrorResult.h"
+#include "mozilla/devtools/DeserializedNode.h"
+#include "mozilla/dom/BindingDeclarations.h"
+#include "mozilla/dom/Nullable.h"
+#include "mozilla/HashFunctions.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/RefCounted.h"
+#include "mozilla/RefPtr.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/UniquePtr.h"
+
+#include "CoreDump.pb.h"
+#include "nsCOMPtr.h"
+#include "nsCRTGlue.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsISupports.h"
+#include "nsWrapperCache.h"
+#include "nsXPCOM.h"
+
+namespace mozilla {
+namespace devtools {
+
+class DominatorTree;
+
+struct NSFreePolicy {
+  void operator()(void* ptr) {
+    NS_Free(ptr);
+  }
+};
+
+using UniqueTwoByteString = UniquePtr<char16_t[], NSFreePolicy>;
+using UniqueOneByteString = UniquePtr<char[], NSFreePolicy>;
+
+class HeapSnapshot final : public nsISupports
+                         , public nsWrapperCache
+{
+  friend struct DeserializedNode;
+  friend struct DeserializedEdge;
+  friend struct DeserializedStackFrame;
+  friend class JS::ubi::Concrete<JS::ubi::DeserializedNode>;
+
+  explicit HeapSnapshot(JSContext* cx, nsISupports* aParent)
+    : timestamp(Nothing())
+    , rootId(0)
+    , nodes(cx)
+    , frames(cx)
+    , mParent(aParent)
+  {
+    MOZ_ASSERT(aParent);
+  };
+
+  // Initialize this HeapSnapshot from the given buffer that contains a
+  // serialized core dump. Do NOT take ownership of the buffer, only borrow it
+  // for the duration of the call. Return false on failure.
+  bool init(JSContext* cx, const uint8_t* buffer, uint32_t size);
+
+  using NodeIdSet = js::HashSet<NodeId>;
+
+  // Save the given `protobuf::Node` message in this `HeapSnapshot` as a
+  // `DeserializedNode`.
+  bool saveNode(const protobuf::Node& node, NodeIdSet& edgeReferents);
+
+  // Save the given `protobuf::StackFrame` message in this `HeapSnapshot` as a
+  // `DeserializedStackFrame`. The saved stack frame's id is returned via the
+  // out parameter.
+  bool saveStackFrame(const protobuf::StackFrame& frame,
+                      StackFrameId& outFrameId);
+
+public:
+  // The maximum number of stack frames that we will serialize into a core
+  // dump. This helps prevent over-recursion in the protobuf library when
+  // deserializing stacks.
+  static const size_t MAX_STACK_DEPTH = 60;
+
+private:
+  // If present, a timestamp in the same units that `PR_Now` gives.
+  Maybe<uint64_t> timestamp;
+
+  // The id of the root node for this deserialized heap graph.
+  NodeId rootId;
+
+  // The set of nodes in this deserialized heap graph, keyed by id.
+  using NodeSet = js::HashSet<DeserializedNode, DeserializedNode::HashPolicy>;
+  NodeSet nodes;
+
+  // The set of stack frames in this deserialized heap graph, keyed by id.
+  using FrameSet = js::HashSet<DeserializedStackFrame,
+                               DeserializedStackFrame::HashPolicy>;
+  FrameSet frames;
+
+  Vector<UniqueTwoByteString> internedTwoByteStrings;
+  Vector<UniqueOneByteString> internedOneByteStrings;
+
+  using StringOrRef = Variant<const std::string*, uint64_t>;
+
+  template<typename CharT,
+           typename InternedStringSet>
+  const CharT* getOrInternString(InternedStringSet& internedStrings,
+                                 Maybe<StringOrRef>& maybeStrOrRef);
+
+protected:
+  nsCOMPtr<nsISupports> mParent;
+
+  virtual ~HeapSnapshot() { }
+
+public:
+  // Create a `HeapSnapshot` from the given buffer that contains a serialized
+  // core dump. Do NOT take ownership of the buffer, only borrow it for the
+  // duration of the call.
+  static already_AddRefed<HeapSnapshot> Create(JSContext* cx,
+                                               dom::GlobalObject& global,
+                                               const uint8_t* buffer,
+                                               uint32_t size,
+                                               ErrorResult& rv);
+
+  // Creates the `$TEMP_DIR/XXXXXX-XXX.fxsnapshot` core dump file that heap
+  // snapshots are serialized into.
+  static already_AddRefed<nsIFile> CreateUniqueCoreDumpFile(ErrorResult& rv,
+                                                            const TimeStamp& now,
+                                                            nsAString& outFilePath);
+
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(HeapSnapshot)
+  MOZ_DECLARE_REFCOUNTED_TYPENAME(HeapSnapshot)
+
+  nsISupports* GetParentObject() const { return mParent; }
+
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+
+  const char16_t* borrowUniqueString(const char16_t* duplicateString,
+                                     size_t length);
+
+  // Get the root node of this heap snapshot's graph.
+  JS::ubi::Node getRoot() {
+    MOZ_ASSERT(nodes.initialized());
+    auto p = nodes.lookup(rootId);
+    MOZ_ASSERT(p);
+    const DeserializedNode& node = *p;
+    return JS::ubi::Node(const_cast<DeserializedNode*>(&node));
+  }
+
+  Maybe<JS::ubi::Node> getNodeById(JS::ubi::Node::Id nodeId) {
+    auto p = nodes.lookup(nodeId);
+    if (!p)
+      return Nothing();
+    return Some(JS::ubi::Node(const_cast<DeserializedNode*>(&*p)));
+  }
+
+  void TakeCensus(JSContext* cx, JS::HandleObject options,
+                  JS::MutableHandleValue rval, ErrorResult& rv);
+
+  void DescribeNode(JSContext* cx, JS::HandleObject breakdown, uint64_t nodeId,
+                    JS::MutableHandleValue rval, ErrorResult& rv);
+
+  already_AddRefed<DominatorTree> ComputeDominatorTree(ErrorResult& rv);
+
+  void ComputeShortestPaths(JSContext*cx, uint64_t start,
+                            const dom::Sequence<uint64_t>& targets,
+                            uint64_t maxNumPaths,
+                            JS::MutableHandleObject results,
+                            ErrorResult& rv);
+
+  dom::Nullable<uint64_t> GetCreationTime() {
+    static const uint64_t maxTime = uint64_t(1) << 53;
+    if (timestamp.isSome() && timestamp.ref() <= maxTime) {
+      return dom::Nullable<uint64_t>(timestamp.ref());
+    }
+
+    return dom::Nullable<uint64_t>();
+  }
+};
+
+// A `CoreDumpWriter` is given the data we wish to save in a core dump and
+// serializes it to disk, or memory, or a socket, etc.
+class CoreDumpWriter
+{
+public:
+  virtual ~CoreDumpWriter() { };
+
+  // Write the given bits of metadata we would like to associate with this core
+  // dump.
+  virtual bool writeMetadata(uint64_t timestamp) = 0;
+
+  enum EdgePolicy : bool {
+    INCLUDE_EDGES = true,
+    EXCLUDE_EDGES = false
+  };
+
+  // Write the given `JS::ubi::Node` to the core dump. The given `EdgePolicy`
+  // dictates whether its outgoing edges should also be written to the core
+  // dump, or excluded.
+  virtual bool writeNode(const JS::ubi::Node& node,
+                         EdgePolicy includeEdges) = 0;
+};
+
+// Serialize the heap graph as seen from `node` with the given `CoreDumpWriter`.
+// If `wantNames` is true, capture edge names. If `zones` is non-null, only
+// capture the sub-graph within the zone set, otherwise capture the whole heap
+// graph. Returns false on failure.
+bool
+WriteHeapGraph(JSContext* cx,
+               const JS::ubi::Node& node,
+               CoreDumpWriter& writer,
+               bool wantNames,
+               JS::CompartmentSet* compartments,
+               JS::AutoCheckCannotGC& noGC);
+
+// Get the mozilla::MallocSizeOf for the current thread's JSRuntime.
+MallocSizeOf GetCurrentThreadDebuggerMallocSizeOf();
+
+} // namespace devtools
+} // namespace mozilla
+
+#endif // mozilla_devtools_HeapSnapshot__