1 files changed, 289 insertions, 0 deletions
diff --git a/js/src/vm/Instrumentation.cpp b/js/src/vm/Instrumentation.cpp
new file mode 100644
index 0000000000..8d9f2863ee
--- /dev/null
+++ b/js/src/vm/Instrumentation.cpp
@@ -0,0 +1,289 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * 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/. */
+
+#include "vm/Instrumentation.h"
+
+#include <iterator>
+
+#include "jsapi.h"
+
+#include "debugger/DebugAPI.h"
+#include "frontend/ParserAtom.h"
+#include "js/Object.h"  // JS::GetReservedSlot
+#include "proxy/DeadObjectProxy.h"
+
+#include "vm/JSObject-inl.h"
+
+namespace js {
+
+RealmInstrumentation::RealmInstrumentation(Zone* zone, JSObject* callback,
+                                           JSObject* dbgObject, uint32_t kinds)
+    : callback(callback), dbgObject(dbgObject), kinds(kinds) {}
+
+void RealmInstrumentation::trace(JSTracer* trc) {
+  TraceEdge(trc, &callback, "RealmInstrumentation::callback");
+  TraceEdge(trc, &dbgObject, "RealmInstrumentation::dbgObject");
+}
+
+enum InstrumentationHolderSlots {
+  RealmInstrumentationSlot,
+  ReservedSlotCount,
+};
+
+static RealmInstrumentation* GetInstrumentation(JSObject* obj) {
+  Value v = JS::GetReservedSlot(obj, RealmInstrumentationSlot);
+  return static_cast<RealmInstrumentation*>(v.isUndefined() ? nullptr
+                                                            : v.toPrivate());
+}
+
+/* static */
+void RealmInstrumentation::holderFinalize(JSFreeOp* fop, JSObject* obj) {
+  RealmInstrumentation* instrumentation = GetInstrumentation(obj);
+  fop->delete_(obj, instrumentation, MemoryUse::RealmInstrumentation);
+}
+
+/* static */
+void RealmInstrumentation::holderTrace(JSTracer* trc, JSObject* obj) {
+  RealmInstrumentation* instrumentation = GetInstrumentation(obj);
+  if (instrumentation) {
+    instrumentation->trace(trc);
+  }
+}
+
+static const JSClassOps InstrumentationHolderClassOps = {
+    nullptr,                               // addProperty
+    nullptr,                               // delProperty
+    nullptr,                               // enumerate
+    nullptr,                               // newEnumerate
+    nullptr,                               // resolve
+    nullptr,                               // mayResolve
+    RealmInstrumentation::holderFinalize,  // finalize
+    nullptr,                               // call
+    nullptr,                               // hasInstance
+    nullptr,                               // construct
+    RealmInstrumentation::holderTrace,     // trace
+};
+
+static const JSClass InstrumentationHolderClass = {
+    "Instrumentation Holder",
+    JSCLASS_HAS_RESERVED_SLOTS(ReservedSlotCount) | JSCLASS_FOREGROUND_FINALIZE,
+    &InstrumentationHolderClassOps, JS_NULL_CLASS_SPEC, JS_NULL_CLASS_EXT};
+
+static const char* instrumentationNames[] = {
+#define DEFINE_INSTRUMENTATION_STRING(_1, String, _2) String,
+    FOR_EACH_INSTRUMENTATION_KIND(DEFINE_INSTRUMENTATION_STRING)
+#undef DEFINE_INSTRUMENTATION_STRING
+};
+
+static bool StringToInstrumentationKind(JSContext* cx, HandleString str,
+                                        InstrumentationKind* result) {
+  for (size_t i = 0; i < std::size(instrumentationNames); i++) {
+    bool match;
+    if (!JS_StringEqualsAscii(cx, str, instrumentationNames[i], &match)) {
+      return false;
+    }
+    if (match) {
+      *result = (InstrumentationKind)(1 << i);
+      return true;
+    }
+  }
+
+  JS_ReportErrorASCII(cx, "Unknown instrumentation kind");
+  return false;
+}
+
+/* static */
+const frontend::ParserAtom* RealmInstrumentation::getInstrumentationKindName(
+    JSContext* cx, frontend::ParserAtomsTable& parserAtoms,
+    InstrumentationKind kind) {
+  for (size_t i = 0; i < std::size(instrumentationNames); i++) {
+    if (kind == (InstrumentationKind)(1 << i)) {
+      return parserAtoms.internAscii(cx, instrumentationNames[i],
+                                     strlen(instrumentationNames[i]));
+    }
+  }
+  MOZ_CRASH("Unexpected instrumentation kind");
+}
+
+/* static */
+bool RealmInstrumentation::install(JSContext* cx, Handle<GlobalObject*> global,
+                                   HandleObject callbackArg,
+                                   HandleObject dbgObjectArg,
+                                   Handle<StringVector> kindStrings) {
+  MOZ_ASSERT(global == cx->global());
+
+  if (global->getInstrumentationHolder()) {
+    JS_ReportErrorASCII(cx, "Global already has instrumentation specified");
+    return false;
+  }
+
+  RootedObject callback(cx, callbackArg);
+  if (!cx->compartment()->wrap(cx, &callback)) {
+    return false;
+  }
+
+  RootedObject dbgObject(cx, dbgObjectArg);
+  if (!cx->compartment()->wrap(cx, &dbgObject)) {
+    return false;
+  }
+
+  uint32_t kinds = 0;
+  for (size_t i = 0; i < kindStrings.length(); i++) {
+    HandleString str = kindStrings[i];
+    InstrumentationKind kind;
+    if (!StringToInstrumentationKind(cx, str, &kind)) {
+      return false;
+    }
+    kinds |= (uint32_t)kind;
+  }
+
+  Rooted<UniquePtr<RealmInstrumentation>> instrumentation(
+      cx,
+      MakeUnique<RealmInstrumentation>(cx->zone(), callback, dbgObject, kinds));
+  if (!instrumentation) {
+    ReportOutOfMemory(cx);
+    return false;
+  }
+
+  JSObject* holder = NewBuiltinClassInstance(cx, &InstrumentationHolderClass);
+  if (!holder) {
+    return false;
+  }
+
+  InitReservedSlot(&holder->as<NativeObject>(), RealmInstrumentationSlot,
+                   instrumentation.release(), MemoryUse::RealmInstrumentation);
+
+  global->setInstrumentationHolder(holder);
+  return true;
+}
+
+/* static */
+bool RealmInstrumentation::setActive(JSContext* cx,
+                                     Handle<GlobalObject*> global,
+                                     Debugger* dbg, bool active) {
+  MOZ_ASSERT(global == cx->global());
+
+  RootedObject holder(cx, global->getInstrumentationHolder());
+  if (!holder) {
+    JS_ReportErrorASCII(cx, "Global does not have instrumentation specified");
+    return false;
+  }
+
+  RealmInstrumentation* instrumentation = GetInstrumentation(holder);
+  MOZ_ASSERT(instrumentation);
+  if (active != instrumentation->active) {
+    instrumentation->active = active;
+
+    // For simplicity, discard all Ion code in the entire zone when
+    // instrumentation activity changes.
+    js::CancelOffThreadIonCompile(cx->runtime());
+    cx->zone()->setPreservingCode(false);
+    cx->zone()->discardJitCode(cx->runtime()->defaultFreeOp(),
+                               Zone::KeepBaselineCode);
+  }
+
+  return true;
+}
+
+/* static */
+bool RealmInstrumentation::isActive(GlobalObject* global) {
+  JSObject* holder = global->getInstrumentationHolder();
+  MOZ_ASSERT(holder);
+
+  RealmInstrumentation* instrumentation = GetInstrumentation(holder);
+  MOZ_ASSERT(instrumentation);
+  return instrumentation->active;
+}
+
+/* static */
+const int32_t* RealmInstrumentation::addressOfActive(GlobalObject* global) {
+  JSObject* holder = global->getInstrumentationHolder();
+  MOZ_ASSERT(holder);
+
+  RealmInstrumentation* instrumentation = GetInstrumentation(holder);
+  MOZ_ASSERT(instrumentation);
+  return &instrumentation->active;
+}
+
+/* static */
+JSObject* RealmInstrumentation::getCallback(GlobalObject* global) {
+  JSObject* holder = global->getInstrumentationHolder();
+  MOZ_ASSERT(holder);
+
+  RealmInstrumentation* instrumentation = GetInstrumentation(holder);
+  MOZ_ASSERT(instrumentation);
+  return instrumentation->callback;
+}
+
+/* static */
+uint32_t RealmInstrumentation::getInstrumentationKinds(GlobalObject* global) {
+  JSObject* holder = global->getInstrumentationHolder();
+  if (!holder) {
+    return 0;
+  }
+
+  RealmInstrumentation* instrumentation = GetInstrumentation(holder);
+  MOZ_ASSERT(instrumentation);
+  return instrumentation->kinds;
+}
+
+/* static */
+bool RealmInstrumentation::getScriptId(JSContext* cx,
+                                       Handle<GlobalObject*> global,
+                                       HandleScript script, int32_t* id) {
+  MOZ_ASSERT(global == cx->global());
+  RootedObject holder(cx, global->getInstrumentationHolder());
+  RealmInstrumentation* instrumentation = GetInstrumentation(holder);
+  MOZ_ASSERT(instrumentation);
+
+  RootedObject dbgObject(cx, UncheckedUnwrap(instrumentation->dbgObject));
+
+  if (IsDeadProxyObject(dbgObject)) {
+    JS_ReportErrorASCII(cx, "Instrumentation debugger object is dead");
+    return false;
+  }
+
+  AutoRealm ar(cx, dbgObject);
+
+  RootedValue idValue(cx);
+  if (!DebugAPI::getScriptInstrumentationId(cx, dbgObject, script, &idValue)) {
+    return false;
+  }
+
+  if (!idValue.isNumber()) {
+    JS_ReportErrorASCII(cx, "Instrumentation ID not set for script");
+    return false;
+  }
+
+  *id = idValue.toNumber();
+  return true;
+}
+
+bool InstrumentationActiveOperation(JSContext* cx, MutableHandleValue rv) {
+  rv.setBoolean(RealmInstrumentation::isActive(cx->global()));
+  return true;
+}
+
+JSObject* InstrumentationCallbackOperation(JSContext* cx) {
+  return RealmInstrumentation::getCallback(cx->global());
+}
+
+bool InstrumentationScriptIdOperation(JSContext* cx, HandleScript script,
+                                      MutableHandleValue rv) {
+  int32_t id;
+  if (!RealmInstrumentation::getScriptId(cx, cx->global(), script, &id)) {
+    return false;
+  }
+  rv.setInt32(id);
+  return true;
+}
+
+bool GlobalHasInstrumentation(JSObject* global) {
+  return global->is<js::GlobalObject>() &&
+         global->as<js::GlobalObject>().getInstrumentationHolder();
+}
+
+}  // namespace js