storage/mozStorageStatementJSHelper.cpp
author Chris H-C <chutten@mozilla.com>
Mon, 04 Jul 2016 11:16:05 -0400
changeset 312997 df28918fe2361f0b54ca9ce4773a29c4c0675d06
parent 268184 e8c7dfe727cd970e2c3294934e2927b14143c205
child 315695 78565156728208e4cb9d20f1a288ba300ceb475f
permissions -rw-r--r--
bug 1218576 - Support remote accumulation via JS histograms. r=gfritzsche The JS histograms, too, need to dispatch their accumulations from child to parent. JSHistograms_Add now only supports histograms that are in gHistogramsMap or that were created in the parent process. After bug 1288745, maybe we'll be able to change this to be less convoluted. MozReview-Commit-ID: 3qTH89YKbGP

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
 * 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 "nsIXPConnect.h"
#include "mozStorageStatement.h"
#include "mozStorageService.h"

#include "nsMemory.h"
#include "nsString.h"
#include "nsServiceManagerUtils.h"

#include "mozStorageStatementJSHelper.h"

#include "mozStorageStatementRow.h"
#include "mozStorageStatementParams.h"

#include "jsapi.h"

namespace mozilla {
namespace storage {

////////////////////////////////////////////////////////////////////////////////
//// Global Functions

static
bool
stepFunc(JSContext *aCtx,
         uint32_t,
         JS::Value *_vp)
{
  nsCOMPtr<nsIXPConnect> xpc(Service::getXPConnect());
  nsCOMPtr<nsIXPConnectWrappedNative> wrapper;
  JSObject *obj = JS_THIS_OBJECT(aCtx, _vp);
  if (!obj) {
    return false;
  }

  nsresult rv =
    xpc->GetWrappedNativeOfJSObject(aCtx, obj, getter_AddRefs(wrapper));
  if (NS_FAILED(rv)) {
    ::JS_ReportError(aCtx, "mozIStorageStatement::step() could not obtain native statement");
    return false;
  }

#ifdef DEBUG
  {
    nsCOMPtr<mozIStorageStatement> isStatement(
      do_QueryInterface(wrapper->Native())
    );
    NS_ASSERTION(isStatement, "How is this not a statement?!");
  }
#endif

  Statement *stmt = static_cast<Statement *>(
    static_cast<mozIStorageStatement *>(wrapper->Native())
  );

  bool hasMore = false;
  rv = stmt->ExecuteStep(&hasMore);
  if (NS_SUCCEEDED(rv) && !hasMore) {
    _vp->setBoolean(false);
    (void)stmt->Reset();
    return true;
  }

  if (NS_FAILED(rv)) {
    ::JS_ReportError(aCtx, "mozIStorageStatement::step() returned an error");
    return false;
  }

  _vp->setBoolean(hasMore);
  return true;
}

////////////////////////////////////////////////////////////////////////////////
//// StatementJSHelper

nsresult
StatementJSHelper::getRow(Statement *aStatement,
                          JSContext *aCtx,
                          JSObject *aScopeObj,
                          JS::Value *_row)
{
  MOZ_ASSERT(NS_IsMainThread());
  nsresult rv;

#ifdef DEBUG
  int32_t state;
  (void)aStatement->GetState(&state);
  NS_ASSERTION(state == mozIStorageStatement::MOZ_STORAGE_STATEMENT_EXECUTING,
               "Invalid state to get the row object - all calls will fail!");
#endif

  if (!aStatement->mStatementRowHolder) {
    JS::RootedObject scope(aCtx, aScopeObj);
    nsCOMPtr<mozIStorageStatementRow> row(new StatementRow(aStatement));
    NS_ENSURE_TRUE(row, NS_ERROR_OUT_OF_MEMORY);

    nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
    nsCOMPtr<nsIXPConnect> xpc(Service::getXPConnect());
    rv = xpc->WrapNativeHolder(
      aCtx,
      ::JS_GetGlobalForObject(aCtx, scope),
      row,
      NS_GET_IID(mozIStorageStatementRow),
      getter_AddRefs(holder)
    );
    NS_ENSURE_SUCCESS(rv, rv);
    RefPtr<StatementRowHolder> rowHolder = new StatementRowHolder(holder);
    aStatement->mStatementRowHolder =
      new nsMainThreadPtrHolder<nsIXPConnectJSObjectHolder>(rowHolder);
  }

  JS::Rooted<JSObject*> obj(aCtx);
  obj = aStatement->mStatementRowHolder->GetJSObject();
  NS_ENSURE_STATE(obj);

  _row->setObject(*obj);
  return NS_OK;
}

nsresult
StatementJSHelper::getParams(Statement *aStatement,
                             JSContext *aCtx,
                             JSObject *aScopeObj,
                             JS::Value *_params)
{
  MOZ_ASSERT(NS_IsMainThread());
  nsresult rv;

#ifdef DEBUG
  int32_t state;
  (void)aStatement->GetState(&state);
  NS_ASSERTION(state == mozIStorageStatement::MOZ_STORAGE_STATEMENT_READY,
               "Invalid state to get the params object - all calls will fail!");
#endif

  if (!aStatement->mStatementParamsHolder) {
    JS::RootedObject scope(aCtx, aScopeObj);
    nsCOMPtr<mozIStorageStatementParams> params =
      new StatementParams(aStatement);
    NS_ENSURE_TRUE(params, NS_ERROR_OUT_OF_MEMORY);

    nsCOMPtr<nsIXPConnectJSObjectHolder> holder;
    nsCOMPtr<nsIXPConnect> xpc(Service::getXPConnect());
    rv = xpc->WrapNativeHolder(
      aCtx,
      ::JS_GetGlobalForObject(aCtx, scope),
      params,
      NS_GET_IID(mozIStorageStatementParams),
      getter_AddRefs(holder)
    );
    NS_ENSURE_SUCCESS(rv, rv);
    RefPtr<StatementParamsHolder> paramsHolder =
      new StatementParamsHolder(holder);
    aStatement->mStatementParamsHolder =
      new nsMainThreadPtrHolder<nsIXPConnectJSObjectHolder>(paramsHolder);
  }

  JS::Rooted<JSObject*> obj(aCtx);
  obj = aStatement->mStatementParamsHolder->GetJSObject();
  NS_ENSURE_STATE(obj);

  _params->setObject(*obj);
  return NS_OK;
}

NS_IMETHODIMP_(MozExternalRefCountType) StatementJSHelper::AddRef() { return 2; }
NS_IMETHODIMP_(MozExternalRefCountType) StatementJSHelper::Release() { return 1; }
NS_INTERFACE_MAP_BEGIN(StatementJSHelper)
  NS_INTERFACE_MAP_ENTRY(nsIXPCScriptable)
  NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END

////////////////////////////////////////////////////////////////////////////////
//// nsIXPCScriptable

#define XPC_MAP_CLASSNAME StatementJSHelper
#define XPC_MAP_QUOTED_CLASSNAME "StatementJSHelper"
#define XPC_MAP_WANT_GETPROPERTY
#define XPC_MAP_WANT_RESOLVE
#define XPC_MAP_FLAGS nsIXPCScriptable::ALLOW_PROP_MODS_DURING_RESOLVE
#include "xpc_map_end.h"

NS_IMETHODIMP
StatementJSHelper::GetProperty(nsIXPConnectWrappedNative *aWrapper,
                               JSContext *aCtx,
                               JSObject *aScopeObj,
                               jsid aId,
                               JS::Value *_result,
                               bool *_retval)
{
  if (!JSID_IS_STRING(aId))
    return NS_OK;

  JS::Rooted<JSObject*> scope(aCtx, aScopeObj);
  JS::Rooted<jsid> id(aCtx, aId);

#ifdef DEBUG
  {
    nsCOMPtr<mozIStorageStatement> isStatement(
                                     do_QueryInterface(aWrapper->Native()));
    NS_ASSERTION(isStatement, "How is this not a statement?!");
  }
#endif

  Statement *stmt = static_cast<Statement *>(
    static_cast<mozIStorageStatement *>(aWrapper->Native())
  );

  JSFlatString *str = JSID_TO_FLAT_STRING(id);
  if (::JS_FlatStringEqualsAscii(str, "row"))
    return getRow(stmt, aCtx, scope, _result);

  if (::JS_FlatStringEqualsAscii(str, "params"))
    return getParams(stmt, aCtx, scope, _result);

  return NS_OK;
}


NS_IMETHODIMP
StatementJSHelper::Resolve(nsIXPConnectWrappedNative *aWrapper,
                           JSContext *aCtx, JSObject *aScopeObj,
                           jsid aId, bool *aResolvedp,
                           bool *_retval)
{
  if (!JSID_IS_STRING(aId))
    return NS_OK;

  JS::RootedObject scope(aCtx, aScopeObj);
  if (::JS_FlatStringEqualsAscii(JSID_TO_FLAT_STRING(aId), "step")) {
    *_retval = ::JS_DefineFunction(aCtx, scope, "step", stepFunc,
                                   0, JSPROP_RESOLVING) != nullptr;
    *aResolvedp = true;
    return NS_OK;
  }
  return NS_OK;
}

////////////////////////////////////////////////////////////////////////////////
//// StatementJSObjectHolder

NS_IMPL_ISUPPORTS(StatementJSObjectHolder, nsIXPConnectJSObjectHolder);

JSObject*
StatementJSObjectHolder::GetJSObject()
{
  return mHolder->GetJSObject();
}

StatementJSObjectHolder::StatementJSObjectHolder(nsIXPConnectJSObjectHolder* aHolder)
  : mHolder(aHolder)
{
  MOZ_ASSERT(NS_IsMainThread());
  MOZ_ASSERT(mHolder);
}

StatementParamsHolder::~StatementParamsHolder()
{
  MOZ_ASSERT(NS_IsMainThread());
  // We are considered dead at this point, so any wrappers for row or params
  // need to lose their reference to the statement.
  nsCOMPtr<nsIXPConnectWrappedNative> wrapper = do_QueryInterface(mHolder);
  nsCOMPtr<mozIStorageStatementParams> iObj = do_QueryWrappedNative(wrapper);
  StatementParams *obj = static_cast<StatementParams *>(iObj.get());
  obj->mStatement = nullptr;
}

StatementRowHolder::~StatementRowHolder()
{
  MOZ_ASSERT(NS_IsMainThread());
  // We are considered dead at this point, so any wrappers for row or params
  // need to lose their reference to the statement.
  nsCOMPtr<nsIXPConnectWrappedNative> wrapper = do_QueryInterface(mHolder);
  nsCOMPtr<mozIStorageStatementRow> iObj = do_QueryWrappedNative(wrapper);
  StatementRow *obj = static_cast<StatementRow *>(iObj.get());
  obj->mStatement = nullptr;
}

} // namespace storage
} // namespace mozilla