gecko-dev/dom/filesystem/compat/CallbackRunnables.cpp
Nicholas Nethercote 34dcc7b852 Bug 1299384 - Use MOZ_MUST_USE with NS_warn_if_impl(). r=erahm.
This change avoids lots of false positives for Coverity's CHECKED_RETURN
warning, caused by NS_WARN_IF's current use in both statement-style and
expression-style.

In the case where the code within the NS_WARN_IF has side-effects, I made the
following change.

> NS_WARN_IF(NS_FAILED(FunctionWithSideEffects()));
> -->
> Unused << NS_WARN_IF(NS_FAILED(FunctionWithSideEffects()));

In the case where the code within the NS_WARN_IF lacks side-effects, I made the
following change.

> NS_WARN_IF(!condWithoutSideEffects);
> -->
> NS_WARNING_ASSERTION(condWithoutSideEffects, "msg");

This has two improvements.
- The condition is not evaluated in non-debug builds.
- The sense of the condition is inverted to the familiar "this condition should
  be true" sense used in assertions.

A common variation on the side-effect-free case is the following.

> nsresult rv = Fn();
> NS_WARN_IF_(NS_FAILED(rv));
> -->
> DebugOnly<nsresult rv> = Fn();
> NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "Fn failed");

--HG--
extra : rebase_source : 58788245021096efa8372a9dc1d597a611d45611
2016-09-02 17:12:24 +10:00

171 lines
4.7 KiB
C++

/* -*- 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 "CallbackRunnables.h"
#include "mozilla/dom/DirectoryBinding.h"
#include "mozilla/dom/DOMError.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/FileBinding.h"
#include "mozilla/dom/FileSystemDirectoryReaderBinding.h"
#include "mozilla/dom/FileSystemFileEntry.h"
#include "mozilla/dom/Promise.h"
#include "mozilla/Unused.h"
#include "nsIGlobalObject.h"
#include "nsPIDOMWindow.h"
namespace mozilla {
namespace dom {
EntryCallbackRunnable::EntryCallbackRunnable(FileSystemEntryCallback* aCallback,
FileSystemEntry* aEntry)
: mCallback(aCallback)
, mEntry(aEntry)
{
MOZ_ASSERT(aCallback);
MOZ_ASSERT(aEntry);
}
NS_IMETHODIMP
EntryCallbackRunnable::Run()
{
mCallback->HandleEvent(*mEntry);
return NS_OK;
}
ErrorCallbackRunnable::ErrorCallbackRunnable(nsIGlobalObject* aGlobalObject,
ErrorCallback* aCallback,
nsresult aError)
: mGlobal(aGlobalObject)
, mCallback(aCallback)
, mError(aError)
{
MOZ_ASSERT(aGlobalObject);
MOZ_ASSERT(aCallback);
MOZ_ASSERT(NS_FAILED(aError));
}
NS_IMETHODIMP
ErrorCallbackRunnable::Run()
{
nsCOMPtr<nsPIDOMWindowInner> window = do_QueryInterface(mGlobal);
if (NS_WARN_IF(!window)) {
return NS_ERROR_FAILURE;
}
RefPtr<DOMError> error = new DOMError(window, mError);
mCallback->HandleEvent(*error);
return NS_OK;
}
EmptyEntriesCallbackRunnable::EmptyEntriesCallbackRunnable(FileSystemEntriesCallback* aCallback)
: mCallback(aCallback)
{
MOZ_ASSERT(aCallback);
}
NS_IMETHODIMP
EmptyEntriesCallbackRunnable::Run()
{
Sequence<OwningNonNull<FileSystemEntry>> sequence;
mCallback->HandleEvent(sequence);
return NS_OK;
}
GetEntryHelper::GetEntryHelper(nsIGlobalObject* aGlobalObject,
FileSystem* aFileSystem,
FileSystemEntryCallback* aSuccessCallback,
ErrorCallback* aErrorCallback,
FileSystemDirectoryEntry::GetInternalType aType)
: mGlobal(aGlobalObject)
, mFileSystem(aFileSystem)
, mSuccessCallback(aSuccessCallback)
, mErrorCallback(aErrorCallback)
, mType(aType)
{
MOZ_ASSERT(aGlobalObject);
MOZ_ASSERT(aFileSystem);
MOZ_ASSERT(aSuccessCallback || aErrorCallback);
}
GetEntryHelper::~GetEntryHelper()
{}
void
GetEntryHelper::ResolvedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue)
{
if(NS_WARN_IF(!aValue.isObject())) {
return;
}
JS::Rooted<JSObject*> obj(aCx, &aValue.toObject());
if (mType == FileSystemDirectoryEntry::eGetFile) {
RefPtr<File> file;
if (NS_FAILED(UNWRAP_OBJECT(File, obj, file))) {
Error(NS_ERROR_DOM_TYPE_MISMATCH_ERR);
return;
}
RefPtr<FileSystemFileEntry> entry =
new FileSystemFileEntry(mGlobal, file, mFileSystem);
mSuccessCallback->HandleEvent(*entry);
return;
}
MOZ_ASSERT(mType == FileSystemDirectoryEntry::eGetDirectory);
RefPtr<Directory> directory;
if (NS_FAILED(UNWRAP_OBJECT(Directory, obj, directory))) {
Error(NS_ERROR_DOM_TYPE_MISMATCH_ERR);
return;
}
RefPtr<FileSystemDirectoryEntry> entry =
new FileSystemDirectoryEntry(mGlobal, directory, mFileSystem);
mSuccessCallback->HandleEvent(*entry);
}
void
GetEntryHelper::RejectedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue)
{
Error(NS_ERROR_DOM_NOT_FOUND_ERR);
}
void
GetEntryHelper::Error(nsresult aError)
{
MOZ_ASSERT(NS_FAILED(aError));
if (mErrorCallback) {
RefPtr<ErrorCallbackRunnable> runnable =
new ErrorCallbackRunnable(mGlobal, mErrorCallback, aError);
DebugOnly<nsresult> rv = NS_DispatchToMainThread(runnable);
NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "NS_DispatchToMainThread failed");
}
}
NS_IMPL_ISUPPORTS0(GetEntryHelper);
/* static */ void
ErrorCallbackHelper::Call(nsIGlobalObject* aGlobal,
const Optional<OwningNonNull<ErrorCallback>>& aErrorCallback,
nsresult aError)
{
MOZ_ASSERT(aGlobal);
MOZ_ASSERT(NS_FAILED(aError));
if (aErrorCallback.WasPassed()) {
RefPtr<ErrorCallbackRunnable> runnable =
new ErrorCallbackRunnable(aGlobal, &aErrorCallback.Value(), aError);
DebugOnly<nsresult> rv = NS_DispatchToMainThread(runnable);
NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "NS_DispatchToMainThread failed");
}
}
} // dom namespace
} // mozilla namespace