gecko/js/jetpack/JetpackChild.cpp

/* -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 8 -*- */
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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
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 * 1.1 (the "License"); you may not use this file except in compliance with
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 *
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 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Firefox.
 *
 * The Initial Developer of the Original Code is
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 * Portions created by the Initial Developer are Copyright (C) 2010
 * the Initial Developer. All Rights Reserved.
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 *
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 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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#include "base/basictypes.h"
#include "jscntxt.h"
#include "nsXULAppAPI.h"

#include "mozilla/jetpack/JetpackChild.h"
#include "mozilla/jetpack/Handle.h"

#include "jsarray.h"

#include <stdio.h>

namespace mozilla {
namespace jetpack {

JetpackChild::JetpackChild()
{
}

JetpackChild::~JetpackChild()
{
}

#define IMPL_METHOD_FLAGS (JSFUN_FAST_NATIVE |  \
                           JSPROP_ENUMERATE | \
                           JSPROP_READONLY | \
                           JSPROP_PERMANENT)
const JSFunctionSpec
JetpackChild::sImplMethods[] = {
  JS_FN("sendMessage", SendMessage, 3, IMPL_METHOD_FLAGS),
  JS_FN("callMessage", CallMessage, 2, IMPL_METHOD_FLAGS),
  JS_FN("registerReceiver", RegisterReceiver, 2, IMPL_METHOD_FLAGS),
  JS_FN("unregisterReceiver", UnregisterReceiver, 2, IMPL_METHOD_FLAGS),
  JS_FN("unregisterReceivers", UnregisterReceivers, 1, IMPL_METHOD_FLAGS),
  JS_FN("wrap", Wrap, 1, IMPL_METHOD_FLAGS),
  JS_FN("createHandle", CreateHandle, 0, IMPL_METHOD_FLAGS),
  JS_FN("createSandbox", CreateSandbox, 0, IMPL_METHOD_FLAGS),
  JS_FN("evalInSandbox", EvalInSandbox, 2, IMPL_METHOD_FLAGS),
  JS_FS_END
};

#undef IMPL_METHOD_FLAGS

const JSClass
JetpackChild::sGlobalClass = {
  "JetpackChild::sGlobalClass", JSCLASS_GLOBAL_FLAGS,
  JS_PropertyStub,  JS_PropertyStub, JS_PropertyStub, JS_PropertyStub,
  JS_EnumerateStub, JS_ResolveStub,  JS_ConvertStub,  JS_FinalizeStub,
  JSCLASS_NO_OPTIONAL_MEMBERS
};

static void
ReportJetpackErrors(JSContext* cx, const char* message, JSErrorReport* report)
{
  const char* filename = "<unknown>";
  if (report && report->filename)
    filename = report->filename;
  int lineno = -1;
  if (report)
    lineno = report->lineno;

  fprintf(stderr, "Jetpack JavaScript Error: %s:%i, %s\n",
          filename, lineno, message);
}

bool
JetpackChild::Init(base::ProcessHandle aParentProcessHandle,
                   MessageLoop* aIOLoop,
                   IPC::Channel* aChannel)
{
  if (!Open(aChannel, aParentProcessHandle, aIOLoop))
    return false;

  if (!(mRuntime = JS_NewRuntime(32L * 1024L * 1024L)) ||
      !(mCx = JS_NewContext(mRuntime, 8192)))
    return false;

  JS_SetErrorReporter(mCx, ReportJetpackErrors);

  {
    JSAutoRequest request(mCx);
    JS_SetContextPrivate(mCx, this);
    JSObject* implGlobal =
      JS_NewGlobalObject(mCx, const_cast<JSClass*>(&sGlobalClass));
    if (!implGlobal ||
        !JS_InitStandardClasses(mCx, implGlobal) ||
        !JS_DefineFunctions(mCx, implGlobal,
                            const_cast<JSFunctionSpec*>(sImplMethods)))
      return false;
  }

  return true;
}

void
JetpackChild::CleanUp()
{
  ClearReceivers();
  JS_DestroyContext(mCx);
  JS_DestroyRuntime(mRuntime);
  JS_ShutDown();
}

void
JetpackChild::ActorDestroy(ActorDestroyReason why)
{
  XRE_ShutdownChildProcess();
}

bool
JetpackChild::RecvSendMessage(const nsString& messageName,
                              const nsTArray<Variant>& data)
{
  JSAutoRequest request(mCx);
  return JetpackActorCommon::RecvMessage(mCx, messageName, data, NULL);
}

bool
JetpackChild::RecvEvalScript(const nsString& code)
{
  JSAutoRequest request(mCx);

  js::AutoValueRooter ignored(mCx);
  (void) JS_EvaluateUCScript(mCx, JS_GetGlobalObject(mCx), code.get(),
                             code.Length(), "", 1, ignored.addr());
  return true;
}

PHandleChild*
JetpackChild::AllocPHandle()
{
  return new HandleChild();
}

bool
JetpackChild::DeallocPHandle(PHandleChild* actor)
{
  delete actor;
  return true;
}

JetpackChild*
JetpackChild::GetThis(JSContext* cx)
{
  JetpackChild* self =
    static_cast<JetpackChild*>(JS_GetContextPrivate(cx));
  JS_ASSERT(cx == self->mCx);
  return self;
}

struct MessageResult {
  nsString msgName;
  nsTArray<Variant> data;
};

static JSBool
MessageCommon(JSContext* cx, uintN argc, jsval* vp,
              MessageResult* result)
{
  if (argc < 1) {
    JS_ReportError(cx, "Message requires a name, at least");
    return JS_FALSE;
  }

  jsval* argv = JS_ARGV(cx, vp);

  JSString* msgNameStr = JS_ValueToString(cx, argv[0]);
  if (!msgNameStr) {
    JS_ReportError(cx, "Could not convert value to string");
    return JS_FALSE;
  }

  result->msgName.Assign((PRUnichar*)JS_GetStringChars(msgNameStr),
                         JS_GetStringLength(msgNameStr));

  result->data.Clear();

  if (!result->data.SetCapacity(argc)) {
    JS_ReportOutOfMemory(cx);
    return JS_FALSE;
  }

  for (uintN i = 1; i < argc; ++i) {
    Variant* vp = result->data.AppendElement();
    if (!JetpackActorCommon::jsval_to_Variant(cx, argv[i], vp)) {
      JS_ReportError(cx, "Invalid message argument at position %d", i);
      return JS_FALSE;
    }
  }

  return JS_TRUE;
}

JSBool
JetpackChild::SendMessage(JSContext* cx, uintN argc, jsval* vp)
{
  MessageResult smr;
  if (!MessageCommon(cx, argc, vp, &smr))
    return JS_FALSE;

  if (!GetThis(cx)->SendSendMessage(smr.msgName, smr.data)) {
    JS_ReportError(cx, "Failed to sendMessage");
    return JS_FALSE;
  }

  return JS_TRUE;
}

JSBool
JetpackChild::CallMessage(JSContext* cx, uintN argc, jsval* vp)
{
  MessageResult smr;
  if (!MessageCommon(cx, argc, vp, &smr))
    return JS_FALSE;

  nsTArray<Variant> results;
  if (!GetThis(cx)->SendCallMessage(smr.msgName, smr.data, &results)) {
    JS_ReportError(cx, "Failed to callMessage");
    return JS_FALSE;
  }

  nsAutoTArray<jsval, 4> jsvals;
  jsval* rvals = jsvals.AppendElements(results.Length());
  if (!rvals) {
    JS_ReportOutOfMemory(cx);
    return JS_FALSE;
  }
  for (PRUint32 i = 0; i < results.Length(); ++i)
    rvals[i] = JSVAL_VOID;
  js::AutoArrayRooter root(cx, results.Length(), rvals);

  for (PRUint32 i = 0; i < results.Length(); ++i)
    if (!jsval_from_Variant(cx, results.ElementAt(i), rvals + i)) {
      JS_ReportError(cx, "Invalid result from handler %d", i);
      return JS_FALSE;
    }

  JSObject* arrObj = JS_NewArrayObject(cx, results.Length(), rvals);
  if (!arrObj) {
    JS_ReportOutOfMemory(cx);
    return JS_FALSE;
  }
  JS_SET_RVAL(cx, vp, OBJECT_TO_JSVAL(arrObj));

  return JS_TRUE;
}

struct ReceiverResult
{
  nsString msgName;
  jsval receiver;
};

static JSBool
ReceiverCommon(JSContext* cx, uintN argc, jsval* vp,
               const char* methodName, uintN arity,
               ReceiverResult* result)
{
  if (argc != arity) {
    JS_ReportError(cx, "%s requires exactly %d arguments", methodName, arity);
    return JS_FALSE;
  }

  // Not currently possible, but think of the future.
  if (arity < 1)
    return JS_TRUE;

  jsval* argv = JS_ARGV(cx, vp);

  JSString* str = JS_ValueToString(cx, argv[0]);
  if (!str) {
    JS_ReportError(cx, "%s expects a stringifiable value as its first argument",
                   methodName);
    return JS_FALSE;
  }

  result->msgName.Assign((PRUnichar*)JS_GetStringChars(str),
                         JS_GetStringLength(str));

  if (arity < 2)
    return JS_TRUE;

  if (!JSVAL_IS_OBJECT(argv[1]) ||
      !JS_ObjectIsFunction(cx, JSVAL_TO_OBJECT(argv[1])))
  {
    JS_ReportError(cx, "%s expects a function as its second argument",
                   methodName);
    return JS_FALSE;
  }

  // GC-safe because argv is rooted.
  result->receiver = argv[1];

  return JS_TRUE;
}

JSBool
JetpackChild::RegisterReceiver(JSContext* cx, uintN argc, jsval* vp)
{
  ReceiverResult rr;
  if (!ReceiverCommon(cx, argc, vp, "registerReceiver", 2, &rr))
    return JS_FALSE;

  JetpackActorCommon* actor = GetThis(cx);
  nsresult rv = actor->RegisterReceiver(cx, rr.msgName, rr.receiver);
  if (NS_FAILED(rv)) {
    JS_ReportOutOfMemory(cx);
    return JS_FALSE;
  }

  return JS_TRUE;
}

JSBool
JetpackChild::UnregisterReceiver(JSContext* cx, uintN argc, jsval* vp)
{
  ReceiverResult rr;
  if (!ReceiverCommon(cx, argc, vp, "unregisterReceiver", 2, &rr))
    return JS_FALSE;

  JetpackActorCommon* actor = GetThis(cx);
  actor->UnregisterReceiver(rr.msgName, rr.receiver);
  return JS_TRUE;
}

JSBool
JetpackChild::UnregisterReceivers(JSContext* cx, uintN argc, jsval* vp)
{
  ReceiverResult rr;
  if (!ReceiverCommon(cx, argc, vp, "unregisterReceivers", 1, &rr))
    return JS_FALSE;

  JetpackActorCommon* actor = GetThis(cx);
  actor->UnregisterReceivers(rr.msgName);
  return JS_TRUE;
}

JSBool
JetpackChild::Wrap(JSContext* cx, uintN argc, jsval* vp)
{
  NS_NOTYETIMPLEMENTED("wrap not yet implemented (depends on bug 563010)");
  return JS_FALSE;
}

JSBool
JetpackChild::CreateHandle(JSContext* cx, uintN argc, jsval* vp)
{
  if (argc > 0) {
    JS_ReportError(cx, "createHandle takes zero arguments");
    return JS_FALSE;
  }

  HandleChild* handle;
  JSObject* hobj;

  PHandleChild* phc = GetThis(cx)->SendPHandleConstructor();
  if (!(handle = static_cast<HandleChild*>(phc)) ||
      !(hobj = handle->ToJSObject(cx))) {
    JS_ReportError(cx, "Failed to construct Handle");
    return JS_FALSE;
  }

  JS_SET_RVAL(cx, vp, OBJECT_TO_JSVAL(hobj));

  return JS_TRUE;
}

JSBool
JetpackChild::CreateSandbox(JSContext* cx, uintN argc, jsval* vp)
{
  if (argc > 0) {
    JS_ReportError(cx, "createSandbox takes zero arguments");
    return JS_FALSE;
  }

  JSObject* obj = JS_NewGlobalObject(cx, const_cast<JSClass*>(&sGlobalClass));
  if (!obj)
    return JS_FALSE;

  JS_SET_RVAL(cx, vp, OBJECT_TO_JSVAL(obj));
  return JS_InitStandardClasses(cx, obj);
}

JSBool
JetpackChild::EvalInSandbox(JSContext* cx, uintN argc, jsval* vp)
{
  if (argc != 2) {
    JS_ReportError(cx, "evalInSandbox takes two arguments");
    return JS_FALSE;
  }

  jsval* argv = JS_ARGV(cx, vp);

  JSObject* obj;
  if (!JSVAL_IS_OBJECT(argv[0]) ||
      !(obj = JSVAL_TO_OBJECT(argv[0])) ||
      &sGlobalClass != JS_GetClass(cx, obj) ||
      obj == JS_GetGlobalObject(cx)) {
    JS_ReportError(cx, "The first argument to evalInSandbox must be a global object created using createSandbox.");
    return JS_FALSE;
  }

  JSString* str = JS_ValueToString(cx, argv[1]);
  if (!str)
    return JS_FALSE;

  js::AutoValueRooter ignored(cx);
  return JS_EvaluateUCScript(cx, obj, JS_GetStringChars(str), JS_GetStringLength(str), "", 1,
                             ignored.addr());
}

} // namespace jetpack
} // namespace mozilla