gecko-dev/dom/system/IOUtils.cpp

1984 строки
66 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 "IOUtils.h"
#include <cstdint>
#include "ErrorList.h"
#include "js/ArrayBuffer.h"
#include "js/JSON.h"
#include "js/Utility.h"
#include "js/experimental/TypedData.h"
#include "jsfriendapi.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/Compression.h"
#include "mozilla/Encoding.h"
#include "mozilla/EndianUtils.h"
#include "mozilla/ErrorNames.h"
#include "mozilla/Maybe.h"
#include "mozilla/ResultExtensions.h"
#include "mozilla/Services.h"
#include "mozilla/Span.h"
#include "mozilla/StaticPtr.h"
#include "mozilla/TextUtils.h"
#include "mozilla/Unused.h"
#include "mozilla/Utf8.h"
#include "mozilla/dom/IOUtilsBinding.h"
#include "mozilla/dom/Promise.h"
#include "nsCOMPtr.h"
#include "nsError.h"
#include "nsFileStreams.h"
#include "nsIDirectoryEnumerator.h"
#include "nsIFile.h"
#include "nsIGlobalObject.h"
#include "nsISupports.h"
#include "nsLocalFile.h"
#include "nsPrintfCString.h"
#include "nsReadableUtils.h"
#include "nsString.h"
#include "nsStringFwd.h"
#include "nsTArray.h"
#include "nsThreadManager.h"
#include "nsXULAppAPI.h"
#include "prerror.h"
#include "prio.h"
#include "prtime.h"
#include "prtypes.h"
#ifndef ANDROID
# include "nsSystemInfo.h"
#endif
#define REJECT_IF_INIT_PATH_FAILED(_file, _path, _promise) \
do { \
if (nsresult _rv = (_file)->InitWithPath((_path)); NS_FAILED(_rv)) { \
(_promise)->MaybeRejectWithOperationError( \
FormatErrorMessage(_rv, "Could not parse path (%s)", \
NS_ConvertUTF16toUTF8(_path).get())); \
return (_promise).forget(); \
} \
} while (0)
static constexpr auto SHUTDOWN_ERROR =
"IOUtils: Shutting down and refusing additional I/O tasks"_ns;
namespace mozilla::dom {
// static helper functions
/**
* Platform-specific (e.g. Windows, Unix) implementations of XPCOM APIs may
* report I/O errors inconsistently. For convenience, this function will attempt
* to match a |nsresult| against known results which imply a file cannot be
* found.
*
* @see nsLocalFileWin.cpp
* @see nsLocalFileUnix.cpp
*/
static bool IsFileNotFound(nsresult aResult) {
return aResult == NS_ERROR_FILE_NOT_FOUND ||
aResult == NS_ERROR_FILE_TARGET_DOES_NOT_EXIST;
}
/**
* Like |IsFileNotFound|, but checks for known results that suggest a file
* is not a directory.
*/
static bool IsNotDirectory(nsresult aResult) {
return aResult == NS_ERROR_FILE_DESTINATION_NOT_DIR ||
aResult == NS_ERROR_FILE_NOT_DIRECTORY;
}
/**
* Formats an error message and appends the error name to the end.
*/
template <typename... Args>
static nsCString FormatErrorMessage(nsresult aError, const char* const aMessage,
Args... aArgs) {
nsPrintfCString msg(aMessage, aArgs...);
if (const char* errName = GetStaticErrorName(aError)) {
msg.AppendPrintf(": %s", errName);
} else {
// In the exceptional case where there is no error name, print the literal
// integer value of the nsresult as an upper case hex value so it can be
// located easily in searchfox.
msg.AppendPrintf(": 0x%" PRIX32, static_cast<uint32_t>(aError));
}
return std::move(msg);
}
static nsCString FormatErrorMessage(nsresult aError,
const char* const aMessage) {
const char* errName = GetStaticErrorName(aError);
if (errName) {
return nsPrintfCString("%s: %s", aMessage, errName);
}
// In the exceptional case where there is no error name, print the literal
// integer value of the nsresult as an upper case hex value so it can be
// located easily in searchfox.
return nsPrintfCString("%s: 0x%" PRIX32, aMessage,
static_cast<uint32_t>(aError));
}
[[nodiscard]] inline bool ToJSValue(
JSContext* aCx, const IOUtils::InternalFileInfo& aInternalFileInfo,
JS::MutableHandle<JS::Value> aValue) {
FileInfo info;
info.mPath.Construct(aInternalFileInfo.mPath);
info.mType.Construct(aInternalFileInfo.mType);
info.mSize.Construct(aInternalFileInfo.mSize);
info.mLastModified.Construct(aInternalFileInfo.mLastModified);
if (aInternalFileInfo.mCreationTime.isSome()) {
info.mCreationTime.Construct(aInternalFileInfo.mCreationTime.ref());
}
info.mPermissions.Construct(aInternalFileInfo.mPermissions);
return ToJSValue(aCx, info, aValue);
}
template <typename T>
static void ResolveJSPromise(Promise* aPromise, T&& aValue) {
if constexpr (std::is_same_v<T, Ok>) {
aPromise->MaybeResolveWithUndefined();
} else {
aPromise->MaybeResolve(std::forward<T>(aValue));
}
}
static void RejectJSPromise(Promise* aPromise, const IOUtils::IOError& aError) {
const auto& errMsg = aError.Message();
switch (aError.Code()) {
case NS_ERROR_FILE_UNRESOLVABLE_SYMLINK:
[[fallthrough]]; // to NS_ERROR_FILE_INVALID_PATH
case NS_ERROR_FILE_TARGET_DOES_NOT_EXIST:
[[fallthrough]]; // to NS_ERROR_FILE_INVALID_PATH
case NS_ERROR_FILE_NOT_FOUND:
[[fallthrough]]; // to NS_ERROR_FILE_INVALID_PATH
case NS_ERROR_FILE_INVALID_PATH:
aPromise->MaybeRejectWithNotFoundError(errMsg.refOr("File not found"_ns));
break;
case NS_ERROR_FILE_IS_LOCKED:
[[fallthrough]]; // to NS_ERROR_FILE_ACCESS_DENIED
case NS_ERROR_FILE_ACCESS_DENIED:
aPromise->MaybeRejectWithNotAllowedError(
errMsg.refOr("Access was denied to the target file"_ns));
break;
case NS_ERROR_FILE_TOO_BIG:
aPromise->MaybeRejectWithNotReadableError(
errMsg.refOr("Target file is too big"_ns));
break;
case NS_ERROR_FILE_NO_DEVICE_SPACE:
aPromise->MaybeRejectWithNotReadableError(
errMsg.refOr("Target device is full"_ns));
break;
case NS_ERROR_FILE_ALREADY_EXISTS:
aPromise->MaybeRejectWithNoModificationAllowedError(
errMsg.refOr("Target file already exists"_ns));
break;
case NS_ERROR_FILE_COPY_OR_MOVE_FAILED:
aPromise->MaybeRejectWithOperationError(
errMsg.refOr("Failed to copy or move the target file"_ns));
break;
case NS_ERROR_FILE_READ_ONLY:
aPromise->MaybeRejectWithReadOnlyError(
errMsg.refOr("Target file is read only"_ns));
break;
case NS_ERROR_FILE_NOT_DIRECTORY:
[[fallthrough]]; // to NS_ERROR_FILE_DESTINATION_NOT_DIR
case NS_ERROR_FILE_DESTINATION_NOT_DIR:
aPromise->MaybeRejectWithInvalidAccessError(
errMsg.refOr("Target file is not a directory"_ns));
break;
case NS_ERROR_FILE_IS_DIRECTORY:
aPromise->MaybeRejectWithInvalidAccessError(
errMsg.refOr("Target file is a directory"_ns));
break;
case NS_ERROR_FILE_UNKNOWN_TYPE:
aPromise->MaybeRejectWithInvalidAccessError(
errMsg.refOr("Target file is of unknown type"_ns));
break;
case NS_ERROR_FILE_NAME_TOO_LONG:
aPromise->MaybeRejectWithOperationError(
errMsg.refOr("Target file path is too long"_ns));
break;
case NS_ERROR_FILE_UNRECOGNIZED_PATH:
aPromise->MaybeRejectWithOperationError(
errMsg.refOr("Target file path is not recognized"_ns));
break;
case NS_ERROR_FILE_DIR_NOT_EMPTY:
aPromise->MaybeRejectWithOperationError(
errMsg.refOr("Target directory is not empty"_ns));
break;
case NS_ERROR_FILE_DEVICE_FAILURE:
[[fallthrough]]; // to NS_ERROR_FILE_FS_CORRUPTED
case NS_ERROR_FILE_FS_CORRUPTED:
aPromise->MaybeRejectWithNotReadableError(
errMsg.refOr("Target file system may be corrupt or unavailable"_ns));
break;
case NS_ERROR_FILE_CORRUPTED:
aPromise->MaybeRejectWithNotReadableError(
errMsg.refOr("Target file could not be read and may be corrupt"_ns));
break;
case NS_ERROR_ILLEGAL_INPUT:
[[fallthrough]]; // NS_ERROR_ILLEGAL_VALUE
case NS_ERROR_ILLEGAL_VALUE:
aPromise->MaybeRejectWithDataError(
errMsg.refOr("Argument is not allowed"_ns));
break;
case NS_ERROR_ABORT:
aPromise->MaybeRejectWithAbortError(errMsg.refOr("Operation aborted"_ns));
break;
default:
aPromise->MaybeRejectWithUnknownError(
errMsg.refOr(FormatErrorMessage(aError.Code(), "Unexpected error")));
}
}
static void RejectShuttingDown(Promise* aPromise) {
RejectJSPromise(aPromise,
IOUtils::IOError(NS_ERROR_ABORT).WithMessage(SHUTDOWN_ERROR));
}
// IOUtils implementation
/* static */
IOUtils::StateMutex IOUtils::sState{"IOUtils::sState"};
/* static */
template <typename OkT, typename Fn>
void IOUtils::DispatchAndResolve(IOUtils::EventQueue* aQueue, Promise* aPromise,
Fn aFunc) {
if (RefPtr<IOPromise<OkT>> p = aQueue->Dispatch<OkT, Fn>(std::move(aFunc))) {
p->Then(
GetCurrentSerialEventTarget(), __func__,
[promise = RefPtr(aPromise)](OkT&& ok) {
ResolveJSPromise(promise, std::forward<OkT>(ok));
},
[promise = RefPtr(aPromise)](const IOError& err) {
RejectJSPromise(promise, err);
});
}
}
/* static */
already_AddRefed<Promise> IOUtils::Read(GlobalObject& aGlobal,
const nsAString& aPath,
const ReadOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
Maybe<uint32_t> toRead = Nothing();
if (!aOptions.mMaxBytes.IsNull()) {
if (aOptions.mMaxBytes.Value() == 0) {
// Resolve with an empty buffer.
nsTArray<uint8_t> arr(0);
promise->MaybeResolve(TypedArrayCreator<Uint8Array>(arr));
return promise.forget();
}
toRead.emplace(aOptions.mMaxBytes.Value());
}
DispatchAndResolve<JsBuffer>(
state.ref()->mEventQueue, promise,
[file = std::move(file), offset = aOptions.mOffset, toRead,
decompress = aOptions.mDecompress]() {
return ReadSync(file, offset, toRead, decompress,
BufferKind::Uint8Array);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::ReadUTF8(GlobalObject& aGlobal,
const nsAString& aPath,
const ReadUTF8Options& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
DispatchAndResolve<JsBuffer>(
state.ref()->mEventQueue, promise,
[file = std::move(file), decompress = aOptions.mDecompress]() {
return ReadUTF8Sync(file, decompress);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::ReadJSON(GlobalObject& aGlobal,
const nsAString& aPath,
const ReadUTF8Options& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
state.ref()
->mEventQueue
->Dispatch<JsBuffer>([file, decompress = aOptions.mDecompress]() {
return ReadUTF8Sync(file, decompress);
})
->Then(
GetCurrentSerialEventTarget(), __func__,
[promise, file](JsBuffer&& aBuffer) {
AutoJSAPI jsapi;
if (NS_WARN_IF(!jsapi.Init(promise->GetGlobalObject()))) {
promise->MaybeRejectWithUnknownError(
"Could not initialize JS API");
return;
}
JSContext* cx = jsapi.cx();
JS::Rooted<JSString*> jsonStr(
cx, IOUtils::JsBuffer::IntoString(cx, std::move(aBuffer)));
if (!jsonStr) {
RejectJSPromise(promise, IOError(NS_ERROR_OUT_OF_MEMORY));
return;
}
JS::Rooted<JS::Value> val(cx);
if (!JS_ParseJSON(cx, jsonStr, &val)) {
JS::Rooted<JS::Value> exn(cx);
if (JS_GetPendingException(cx, &exn)) {
JS_ClearPendingException(cx);
promise->MaybeReject(exn);
} else {
RejectJSPromise(
promise,
IOError(NS_ERROR_DOM_UNKNOWN_ERR)
.WithMessage(
"ParseJSON threw an uncatchable exception "
"while parsing file(%s)",
file->HumanReadablePath().get()));
}
return;
}
promise->MaybeResolve(val);
},
[promise](const IOError& aErr) { RejectJSPromise(promise, aErr); });
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::Write(GlobalObject& aGlobal,
const nsAString& aPath,
const Uint8Array& aData,
const WriteOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
aData.ComputeState();
auto buf = Buffer<uint8_t>::CopyFrom(Span(aData.Data(), aData.Length()));
if (buf.isNothing()) {
promise->MaybeRejectWithOperationError(
"Out of memory: Could not allocate buffer while writing to file");
return promise.forget();
}
auto opts = InternalWriteOpts::FromBinding(aOptions);
if (opts.isErr()) {
RejectJSPromise(promise, opts.unwrapErr());
return promise.forget();
}
DispatchAndResolve<uint32_t>(
state.ref()->mEventQueue, promise,
[file = std::move(file), buf = std::move(*buf),
opts = opts.unwrap()]() { return WriteSync(file, buf, opts); });
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::WriteUTF8(GlobalObject& aGlobal,
const nsAString& aPath,
const nsACString& aString,
const WriteOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
auto opts = InternalWriteOpts::FromBinding(aOptions);
if (opts.isErr()) {
RejectJSPromise(promise, opts.unwrapErr());
return promise.forget();
}
DispatchAndResolve<uint32_t>(
state.ref()->mEventQueue, promise,
[file = std::move(file), str = nsCString(aString),
opts = opts.unwrap()]() {
return WriteSync(file, AsBytes(Span(str)), opts);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
static bool AppendJsonAsUtf8(const char16_t* aData, uint32_t aLen, void* aStr) {
nsCString* str = static_cast<nsCString*>(aStr);
return AppendUTF16toUTF8(Span<const char16_t>(aData, aLen), *str, fallible);
}
/* static */
already_AddRefed<Promise> IOUtils::WriteJSON(GlobalObject& aGlobal,
const nsAString& aPath,
JS::Handle<JS::Value> aValue,
const WriteOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
auto opts = InternalWriteOpts::FromBinding(aOptions);
if (opts.isErr()) {
RejectJSPromise(promise, opts.unwrapErr());
return promise.forget();
}
if (opts.inspect().mMode == WriteMode::Append) {
promise->MaybeRejectWithNotSupportedError(
"IOUtils.writeJSON does not support appending to files."_ns);
return promise.forget();
}
JSContext* cx = aGlobal.Context();
JS::Rooted<JS::Value> rootedValue(cx, aValue);
nsCString utf8Str;
if (!JS_Stringify(cx, &rootedValue, nullptr, JS::NullHandleValue,
AppendJsonAsUtf8, &utf8Str)) {
JS::Rooted<JS::Value> exn(cx, JS::UndefinedValue());
if (JS_GetPendingException(cx, &exn)) {
JS_ClearPendingException(cx);
promise->MaybeReject(exn);
} else {
RejectJSPromise(promise,
IOError(NS_ERROR_DOM_UNKNOWN_ERR)
.WithMessage("Could not serialize object to JSON"));
}
return promise.forget();
}
DispatchAndResolve<uint32_t>(
state.ref()->mEventQueue, promise,
[file = std::move(file), utf8Str = std::move(utf8Str),
opts = opts.unwrap()]() {
return WriteSync(file, AsBytes(Span(utf8Str)), opts);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::Move(GlobalObject& aGlobal,
const nsAString& aSourcePath,
const nsAString& aDestPath,
const MoveOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> sourceFile = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(sourceFile, aSourcePath, promise);
nsCOMPtr<nsIFile> destFile = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(destFile, aDestPath, promise);
DispatchAndResolve<Ok>(
state.ref()->mEventQueue, promise,
[sourceFile = std::move(sourceFile), destFile = std::move(destFile),
noOverwrite = aOptions.mNoOverwrite]() {
return MoveSync(sourceFile, destFile, noOverwrite);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::Remove(GlobalObject& aGlobal,
const nsAString& aPath,
const RemoveOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
DispatchAndResolve<Ok>(
state.ref()->mEventQueue, promise,
[file = std::move(file), ignoreAbsent = aOptions.mIgnoreAbsent,
recursive = aOptions.mRecursive]() {
return RemoveSync(file, ignoreAbsent, recursive);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::MakeDirectory(
GlobalObject& aGlobal, const nsAString& aPath,
const MakeDirectoryOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
DispatchAndResolve<Ok>(
state.ref()->mEventQueue, promise,
[file = std::move(file), createAncestors = aOptions.mCreateAncestors,
ignoreExisting = aOptions.mIgnoreExisting,
permissions = aOptions.mPermissions]() {
return MakeDirectorySync(file, createAncestors, ignoreExisting,
permissions);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
already_AddRefed<Promise> IOUtils::Stat(GlobalObject& aGlobal,
const nsAString& aPath) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
DispatchAndResolve<InternalFileInfo>(
state.ref()->mEventQueue, promise,
[file = std::move(file)]() { return StatSync(file); });
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::Copy(GlobalObject& aGlobal,
const nsAString& aSourcePath,
const nsAString& aDestPath,
const CopyOptions& aOptions) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> sourceFile = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(sourceFile, aSourcePath, promise);
nsCOMPtr<nsIFile> destFile = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(destFile, aDestPath, promise);
DispatchAndResolve<Ok>(
state.ref()->mEventQueue, promise,
[sourceFile = std::move(sourceFile), destFile = std::move(destFile),
noOverwrite = aOptions.mNoOverwrite,
recursive = aOptions.mRecursive]() {
return CopySync(sourceFile, destFile, noOverwrite, recursive);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::Touch(
GlobalObject& aGlobal, const nsAString& aPath,
const Optional<int64_t>& aModification) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
Maybe<int64_t> newTime = Nothing();
if (aModification.WasPassed()) {
newTime = Some(aModification.Value());
}
DispatchAndResolve<int64_t>(state.ref()->mEventQueue, promise,
[file = std::move(file), newTime]() {
return TouchSync(file, newTime);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::GetChildren(GlobalObject& aGlobal,
const nsAString& aPath) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
DispatchAndResolve<nsTArray<nsString>>(
state.ref()->mEventQueue, promise,
[file = std::move(file)]() { return GetChildrenSync(file); });
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::SetPermissions(GlobalObject& aGlobal,
const nsAString& aPath,
uint32_t aPermissions,
const bool aHonorUmask) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
#if defined(XP_UNIX) && !defined(ANDROID)
if (aHonorUmask) {
aPermissions &= ~nsSystemInfo::gUserUmask;
}
#endif
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
DispatchAndResolve<Ok>(
state.ref()->mEventQueue, promise,
[file = std::move(file), permissions = aPermissions]() {
return SetPermissionsSync(file, permissions);
});
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::Exists(GlobalObject& aGlobal,
const nsAString& aPath) {
MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
RefPtr<Promise> promise = CreateJSPromise(aGlobal);
if (!promise) {
return nullptr;
}
if (auto state = GetState()) {
nsCOMPtr<nsIFile> file = new nsLocalFile();
REJECT_IF_INIT_PATH_FAILED(file, aPath, promise);
DispatchAndResolve<bool>(
state.ref()->mEventQueue, promise,
[file = std::move(file)]() { return ExistsSync(file); });
} else {
RejectShuttingDown(promise);
}
return promise.forget();
}
/* static */
already_AddRefed<Promise> IOUtils::CreateJSPromise(GlobalObject& aGlobal) {
ErrorResult er;
nsCOMPtr<nsIGlobalObject> global = do_QueryInterface(aGlobal.GetAsSupports());
RefPtr<Promise> promise = Promise::Create(global, er);
if (er.Failed()) {
return nullptr;
}
MOZ_ASSERT(promise);
return do_AddRef(promise);
}
/* static */
Result<IOUtils::JsBuffer, IOUtils::IOError> IOUtils::ReadSync(
nsIFile* aFile, const uint32_t aOffset, const Maybe<uint32_t> aMaxBytes,
const bool aDecompress, IOUtils::BufferKind aBufferKind) {
MOZ_ASSERT(!NS_IsMainThread());
if (aMaxBytes.isSome() && aDecompress) {
return Err(
IOError(NS_ERROR_ILLEGAL_INPUT)
.WithMessage(
"The `maxBytes` and `decompress` options are not compatible"));
}
RefPtr<nsFileStream> stream = new nsFileStream();
if (nsresult rv =
stream->Init(aFile, PR_RDONLY | nsIFile::OS_READAHEAD, 0666, 0);
NS_FAILED(rv)) {
return Err(IOError(rv).WithMessage("Could not open the file at %s",
aFile->HumanReadablePath().get()));
}
int64_t bufSize = 0;
if (aMaxBytes.isNothing()) {
// Limitation: We cannot read files that are larger than the max size of a
// TypedArray (UINT32_MAX bytes). Reject if the file is too
// big to be read.
int64_t streamSize = -1;
if (nsresult rv = stream->GetSize(&streamSize); NS_FAILED(rv)) {
return Err(IOError(NS_ERROR_FILE_ACCESS_DENIED)
.WithMessage("Could not get info for the file at %s",
aFile->HumanReadablePath().get()));
}
MOZ_RELEASE_ASSERT(streamSize >= 0);
if (streamSize > static_cast<int64_t>(UINT32_MAX)) {
return Err(
IOError(NS_ERROR_FILE_TOO_BIG)
.WithMessage("Could not read the file at %s because it is too "
"large(size=%" PRId64 " bytes)",
aFile->HumanReadablePath().get(), streamSize));
}
bufSize = static_cast<uint32_t>(streamSize);
if (aOffset >= bufSize) {
bufSize = 0;
} else {
bufSize = bufSize - aOffset;
}
} else {
bufSize = aMaxBytes.value();
}
if (aOffset > 0) {
if (nsresult rv = stream->Seek(PR_SEEK_SET, aOffset); NS_FAILED(rv)) {
return Err(IOError(rv).WithMessage(
"Could not seek to position %" PRId64 " in file %s", aOffset,
aFile->HumanReadablePath().get()));
}
}
JsBuffer buffer = JsBuffer::CreateEmpty(aBufferKind);
if (bufSize > 0) {
auto result = JsBuffer::Create(aBufferKind, bufSize);
if (result.isErr()) {
return result.propagateErr();
}
buffer = result.unwrap();
Span<char> toRead = buffer.BeginWriting();
// Read the file from disk.
uint32_t totalRead = 0;
while (totalRead != bufSize) {
uint32_t bytesRead = 0;
if (nsresult rv =
stream->Read(toRead.Elements(), bufSize - totalRead, &bytesRead);
NS_FAILED(rv)) {
return Err(IOError(rv).WithMessage(
"Encountered an unexpected error while reading file(%s)",
aFile->HumanReadablePath().get()));
}
if (bytesRead == 0) {
break;
}
totalRead += bytesRead;
toRead = toRead.From(bytesRead);
}
buffer.SetLength(totalRead);
}
// Decompress the file contents, if required.
if (aDecompress) {
return MozLZ4::Decompress(AsBytes(buffer.BeginReading()), aBufferKind);
}
return std::move(buffer);
}
/* static */
Result<IOUtils::JsBuffer, IOUtils::IOError> IOUtils::ReadUTF8Sync(
nsIFile* aFile, bool aDecompress) {
auto result = ReadSync(aFile, 0, Nothing{}, aDecompress, BufferKind::String);
if (result.isErr()) {
return result.propagateErr();
}
JsBuffer buffer = result.unwrap();
if (!IsUtf8(buffer.BeginReading())) {
return Err(
IOError(NS_ERROR_FILE_CORRUPTED)
.WithMessage(
"Could not read file(%s) because it is not UTF-8 encoded",
aFile->HumanReadablePath().get()));
}
return buffer;
}
/* static */
Result<uint32_t, IOUtils::IOError> IOUtils::WriteSync(
nsIFile* aFile, const Span<const uint8_t>& aByteArray,
const IOUtils::InternalWriteOpts& aOptions) {
MOZ_ASSERT(!NS_IsMainThread());
nsIFile* backupFile = aOptions.mBackupFile;
nsIFile* tempFile = aOptions.mTmpFile;
bool exists = false;
MOZ_TRY(aFile->Exists(&exists));
if (exists && aOptions.mMode == WriteMode::Create) {
return Err(IOError(NS_ERROR_DOM_TYPE_MISMATCH_ERR)
.WithMessage("Refusing to overwrite the file at %s\n"
"Specify `mode: \"overwrite\"` to allow "
"overwriting the destination",
aFile->HumanReadablePath().get()));
}
// If backupFile was specified, perform the backup as a move.
if (exists && backupFile) {
// We copy `destFile` here to a new `nsIFile` because
// `nsIFile::MoveToFollowingLinks` will update the path of the file. If we
// did not do this, we would end up having `destFile` point to the same
// location as `backupFile`. Then, when we went to write to `destFile`, we
// would end up overwriting `backupFile` and never actually write to the
// file we were supposed to.
nsCOMPtr<nsIFile> toMove;
MOZ_ALWAYS_SUCCEEDS(aFile->Clone(getter_AddRefs(toMove)));
bool noOverwrite = aOptions.mMode == WriteMode::Create;
if (MoveSync(toMove, backupFile, noOverwrite).isErr()) {
return Err(IOError(NS_ERROR_FILE_COPY_OR_MOVE_FAILED)
.WithMessage("Failed to backup the source file(%s) to %s",
aFile->HumanReadablePath().get(),
backupFile->HumanReadablePath().get()));
}
}
// If tempFile was specified, we will write to there first, then perform a
// move to ensure the file ends up at the final requested destination.
nsIFile* writeFile;
if (tempFile) {
writeFile = tempFile;
} else {
writeFile = aFile;
}
int32_t flags = PR_WRONLY;
switch (aOptions.mMode) {
case WriteMode::Overwrite:
flags |= PR_TRUNCATE | PR_CREATE_FILE;
break;
case WriteMode::Append:
flags |= PR_APPEND;
break;
case WriteMode::Create:
flags |= PR_CREATE_FILE | PR_EXCL;
break;
default:
MOZ_CRASH("IOUtils: unknown write mode");
}
if (aOptions.mFlush) {
flags |= PR_SYNC;
}
// Try to perform the write and ensure that the file is closed before
// continuing.
uint32_t totalWritten = 0;
{
// Compress the byte array if required.
nsTArray<uint8_t> compressed;
Span<const char> bytes;
if (aOptions.mCompress) {
auto rv = MozLZ4::Compress(aByteArray);
if (rv.isErr()) {
return rv.propagateErr();
}
compressed = rv.unwrap();
bytes = Span(reinterpret_cast<const char*>(compressed.Elements()),
compressed.Length());
} else {
bytes = Span(reinterpret_cast<const char*>(aByteArray.Elements()),
aByteArray.Length());
}
RefPtr<nsFileOutputStream> stream = new nsFileOutputStream();
if (nsresult rv = stream->Init(writeFile, flags, 0666, 0); NS_FAILED(rv)) {
// Normalize platform-specific errors for opening a directory to an access
// denied error.
if (rv == nsresult::NS_ERROR_FILE_IS_DIRECTORY) {
rv = NS_ERROR_FILE_ACCESS_DENIED;
}
return Err(
IOError(rv).WithMessage("Could not open the file at %s for writing",
writeFile->HumanReadablePath().get()));
}
// nsFileStream::Write uses PR_Write under the hood, which accepts a
// *int32_t* for the chunk size.
uint32_t chunkSize = INT32_MAX;
Span<const char> pendingBytes = bytes;
while (pendingBytes.Length() > 0) {
if (pendingBytes.Length() < chunkSize) {
chunkSize = pendingBytes.Length();
}
uint32_t bytesWritten = 0;
if (nsresult rv =
stream->Write(pendingBytes.Elements(), chunkSize, &bytesWritten);
NS_FAILED(rv)) {
return Err(IOError(rv).WithMessage(
"Could not write chunk (size = %" PRIu32
") to file %s. The file may be corrupt.",
chunkSize, writeFile->HumanReadablePath().get()));
}
pendingBytes = pendingBytes.From(bytesWritten);
totalWritten += bytesWritten;
}
}
// If tempFile was passed, check destFile against writeFile and, if they
// differ, the operation is finished by performing a move.
if (tempFile) {
nsAutoStringN<256> destPath;
nsAutoStringN<256> writePath;
MOZ_ALWAYS_SUCCEEDS(aFile->GetPath(destPath));
MOZ_ALWAYS_SUCCEEDS(writeFile->GetPath(writePath));
// nsIFile::MoveToFollowingLinks will only update the path of the file if
// the move succeeds.
if (destPath != writePath) {
if (aOptions.mTmpFile) {
bool isDir = false;
if (nsresult rv = aFile->IsDirectory(&isDir);
NS_FAILED(rv) && !IsFileNotFound(rv)) {
return Err(IOError(rv).WithMessage("Could not stat the file at %s",
aFile->HumanReadablePath().get()));
}
// If we attempt to write to a directory *without* a temp file, we get a
// permission error.
//
// However, if we are writing to a temp file first, when we copy the
// temp file over the destination file, we actually end up copying it
// inside the directory, which is not what we want. In this case, we are
// just going to bail out early.
if (isDir) {
return Err(
IOError(NS_ERROR_FILE_ACCESS_DENIED)
.WithMessage("Could not open the file at %s for writing",
aFile->HumanReadablePath().get()));
}
}
if (MoveSync(writeFile, aFile, /* aNoOverwrite = */ false).isErr()) {
return Err(
IOError(NS_ERROR_FILE_COPY_OR_MOVE_FAILED)
.WithMessage(
"Could not move temporary file(%s) to destination(%s)",
writeFile->HumanReadablePath().get(),
aFile->HumanReadablePath().get()));
}
}
}
return totalWritten;
}
/* static */
Result<Ok, IOUtils::IOError> IOUtils::MoveSync(nsIFile* aSourceFile,
nsIFile* aDestFile,
bool aNoOverwrite) {
MOZ_ASSERT(!NS_IsMainThread());
// Ensure the source file exists before continuing. If it doesn't exist,
// subsequent operations can fail in different ways on different platforms.
bool srcExists = false;
MOZ_TRY(aSourceFile->Exists(&srcExists));
if (!srcExists) {
return Err(
IOError(NS_ERROR_FILE_NOT_FOUND)
.WithMessage(
"Could not move source file(%s) because it does not exist",
aSourceFile->HumanReadablePath().get()));
}
return CopyOrMoveSync(&nsIFile::MoveToFollowingLinks, "move", aSourceFile,
aDestFile, aNoOverwrite);
}
/* static */
Result<Ok, IOUtils::IOError> IOUtils::CopySync(nsIFile* aSourceFile,
nsIFile* aDestFile,
bool aNoOverwrite,
bool aRecursive) {
MOZ_ASSERT(!NS_IsMainThread());
// Ensure the source file exists before continuing. If it doesn't exist,
// subsequent operations can fail in different ways on different platforms.
bool srcExists;
MOZ_TRY(aSourceFile->Exists(&srcExists));
if (!srcExists) {
return Err(
IOError(NS_ERROR_FILE_NOT_FOUND)
.WithMessage(
"Could not copy source file(%s) because it does not exist",
aSourceFile->HumanReadablePath().get()));
}
// If source is a directory, fail immediately unless the recursive option is
// true.
bool srcIsDir = false;
MOZ_TRY(aSourceFile->IsDirectory(&srcIsDir));
if (srcIsDir && !aRecursive) {
return Err(
IOError(NS_ERROR_FILE_COPY_OR_MOVE_FAILED)
.WithMessage(
"Refused to copy source directory(%s) to the destination(%s)\n"
"Specify the `recursive: true` option to allow copying "
"directories",
aSourceFile->HumanReadablePath().get(),
aDestFile->HumanReadablePath().get()));
}
return CopyOrMoveSync(&nsIFile::CopyToFollowingLinks, "copy", aSourceFile,
aDestFile, aNoOverwrite);
}
/* static */
template <typename CopyOrMoveFn>
Result<Ok, IOUtils::IOError> IOUtils::CopyOrMoveSync(CopyOrMoveFn aMethod,
const char* aMethodName,
nsIFile* aSource,
nsIFile* aDest,
bool aNoOverwrite) {
MOZ_ASSERT(!NS_IsMainThread());
// Case 1: Destination is an existing directory. Copy/move source into dest.
bool destIsDir = false;
bool destExists = true;
nsresult rv = aDest->IsDirectory(&destIsDir);
if (NS_SUCCEEDED(rv) && destIsDir) {
rv = (aSource->*aMethod)(aDest, u""_ns);
if (NS_FAILED(rv)) {
return Err(IOError(rv).WithMessage(
"Could not %s source file(%s) to destination directory(%s)",
aMethodName, aSource->HumanReadablePath().get(),
aDest->HumanReadablePath().get()));
}
return Ok();
}
if (NS_FAILED(rv)) {
if (!IsFileNotFound(rv)) {
// It's ok if the dest file doesn't exist. Case 2 handles this below.
// Bail out early for any other kind of error though.
return Err(IOError(rv));
}
destExists = false;
}
// Case 2: Destination is a file which may or may not exist.
// Try to copy or rename the source to the destination.
// If the destination exists and the source is not a regular file,
// then this may fail.
if (aNoOverwrite && destExists) {
return Err(
IOError(NS_ERROR_FILE_ALREADY_EXISTS)
.WithMessage(
"Could not %s source file(%s) to destination(%s) because the "
"destination already exists and overwrites are not allowed\n"
"Specify the `noOverwrite: false` option to mitigate this "
"error",
aMethodName, aSource->HumanReadablePath().get(),
aDest->HumanReadablePath().get()));
}
if (destExists && !destIsDir) {
// If the source file is a directory, but the target is a file, abort early.
// Different implementations of |CopyTo| and |MoveTo| seem to handle this
// error case differently (or not at all), so we explicitly handle it here.
bool srcIsDir = false;
MOZ_TRY(aSource->IsDirectory(&srcIsDir));
if (srcIsDir) {
return Err(IOError(NS_ERROR_FILE_DESTINATION_NOT_DIR)
.WithMessage("Could not %s the source directory(%s) to "
"the destination(%s) because the destination "
"is not a directory",
aMethodName,
aSource->HumanReadablePath().get(),
aDest->HumanReadablePath().get()));
}
}
nsCOMPtr<nsIFile> destDir;
nsAutoString destName;
MOZ_TRY(aDest->GetLeafName(destName));
MOZ_TRY(aDest->GetParent(getter_AddRefs(destDir)));
// We know `destName` is a file and therefore must have a parent directory.
MOZ_RELEASE_ASSERT(destDir);
// NB: if destDir doesn't exist, then |CopyToFollowingLinks| or
// |MoveToFollowingLinks| will create it.
rv = (aSource->*aMethod)(destDir, destName);
if (NS_FAILED(rv)) {
return Err(IOError(rv).WithMessage(
"Could not %s the source file(%s) to the destination(%s)", aMethodName,
aSource->HumanReadablePath().get(), aDest->HumanReadablePath().get()));
}
return Ok();
}
/* static */
Result<Ok, IOUtils::IOError> IOUtils::RemoveSync(nsIFile* aFile,
bool aIgnoreAbsent,
bool aRecursive) {
MOZ_ASSERT(!NS_IsMainThread());
nsresult rv = aFile->Remove(aRecursive);
if (aIgnoreAbsent && IsFileNotFound(rv)) {
return Ok();
}
if (NS_FAILED(rv)) {
IOError err(rv);
if (IsFileNotFound(rv)) {
return Err(err.WithMessage(
"Could not remove the file at %s because it does not exist.\n"
"Specify the `ignoreAbsent: true` option to mitigate this error",
aFile->HumanReadablePath().get()));
}
if (rv == NS_ERROR_FILE_DIR_NOT_EMPTY) {
return Err(err.WithMessage(
"Could not remove the non-empty directory at %s.\n"
"Specify the `recursive: true` option to mitigate this error",
aFile->HumanReadablePath().get()));
}
return Err(err.WithMessage("Could not remove the file at %s",
aFile->HumanReadablePath().get()));
}
return Ok();
}
/* static */
Result<Ok, IOUtils::IOError> IOUtils::MakeDirectorySync(nsIFile* aFile,
bool aCreateAncestors,
bool aIgnoreExisting,
int32_t aMode) {
MOZ_ASSERT(!NS_IsMainThread());
nsCOMPtr<nsIFile> parent;
MOZ_TRY(aFile->GetParent(getter_AddRefs(parent)));
if (!parent) {
// If we don't have a parent directory, we were called with a
// root directory. If the directory doesn't already exist (e.g., asking
// for a drive on Windows that does not exist), we will not be able to
// create it.
//
// Calling `nsLocalFile::Create()` on Windows can fail with
// `NS_ERROR_ACCESS_DENIED` trying to create a root directory, but we
// would rather the call succeed, so return early if the directory exists.
//
// Otherwise, we fall through to `nsiFile::Create()` and let it fail there
// instead.
bool exists = false;
MOZ_TRY(aFile->Exists(&exists));
if (exists) {
return Ok();
}
}
nsresult rv =
aFile->Create(nsIFile::DIRECTORY_TYPE, aMode, !aCreateAncestors);
if (NS_FAILED(rv)) {
if (rv == NS_ERROR_FILE_ALREADY_EXISTS) {
// NB: We may report a success only if the target is an existing
// directory. We don't want to silence errors that occur if the target is
// an existing file, since trying to create a directory where a regular
// file exists may be indicative of a logic error.
bool isDirectory;
MOZ_TRY(aFile->IsDirectory(&isDirectory));
if (!isDirectory) {
return Err(IOError(NS_ERROR_FILE_NOT_DIRECTORY)
.WithMessage("Could not create directory because the "
"target file(%s) exists "
"and is not a directory",
aFile->HumanReadablePath().get()));
}
// The directory exists.
// The caller may suppress this error.
if (aIgnoreExisting) {
return Ok();
}
// Otherwise, forward it.
return Err(IOError(rv).WithMessage(
"Could not create directory because it already exists at %s\n"
"Specify the `ignoreExisting: true` option to mitigate this "
"error",
aFile->HumanReadablePath().get()));
}
return Err(IOError(rv).WithMessage("Could not create directory at %s",
aFile->HumanReadablePath().get()));
}
return Ok();
}
Result<IOUtils::InternalFileInfo, IOUtils::IOError> IOUtils::StatSync(
nsIFile* aFile) {
MOZ_ASSERT(!NS_IsMainThread());
InternalFileInfo info;
MOZ_ALWAYS_SUCCEEDS(aFile->GetPath(info.mPath));
bool isRegular = false;
// IsFile will stat and cache info in the file object. If the file doesn't
// exist, or there is an access error, we'll discover it here.
// Any subsequent errors are unexpected and will just be forwarded.
nsresult rv = aFile->IsFile(&isRegular);
if (NS_FAILED(rv)) {
IOError err(rv);
if (IsFileNotFound(rv)) {
return Err(
err.WithMessage("Could not stat file(%s) because it does not exist",
aFile->HumanReadablePath().get()));
}
return Err(err);
}
// Now we can populate the info object by querying the file.
info.mType = FileType::Regular;
if (!isRegular) {
bool isDir = false;
MOZ_TRY(aFile->IsDirectory(&isDir));
info.mType = isDir ? FileType::Directory : FileType::Other;
}
int64_t size = -1;
if (info.mType == FileType::Regular) {
MOZ_TRY(aFile->GetFileSize(&size));
}
info.mSize = size;
PRTime lastModified = 0;
MOZ_TRY(aFile->GetLastModifiedTime(&lastModified));
info.mLastModified = static_cast<int64_t>(lastModified);
PRTime creationTime = 0;
if (nsresult rv = aFile->GetCreationTime(&creationTime); NS_SUCCEEDED(rv)) {
info.mCreationTime.emplace(static_cast<int64_t>(creationTime));
} else if (NS_FAILED(rv) && rv != NS_ERROR_NOT_IMPLEMENTED) {
// This field is only supported on some platforms.
return Err(IOError(rv));
}
MOZ_TRY(aFile->GetPermissions(&info.mPermissions));
return info;
}
/* static */
Result<int64_t, IOUtils::IOError> IOUtils::TouchSync(
nsIFile* aFile, const Maybe<int64_t>& aNewModTime) {
MOZ_ASSERT(!NS_IsMainThread());
int64_t now = aNewModTime.valueOrFrom([]() {
// NB: PR_Now reports time in microseconds since the Unix epoch
// (1970-01-01T00:00:00Z). Both nsLocalFile's lastModifiedTime and
// JavaScript's Date primitive values are to be expressed in
// milliseconds since Epoch.
int64_t nowMicros = PR_Now();
int64_t nowMillis = nowMicros / PR_USEC_PER_MSEC;
return nowMillis;
});
// nsIFile::SetLastModifiedTime will *not* do what is expected when passed 0
// as an argument. Rather than setting the time to 0, it will recalculate the
// system time and set it to that value instead. We explicit forbid this,
// because this side effect is surprising.
//
// If it ever becomes possible to set a file time to 0, this check should be
// removed, though this use case seems rare.
if (now == 0) {
return Err(
IOError(NS_ERROR_ILLEGAL_VALUE)
.WithMessage(
"Refusing to set the modification time of file(%s) to 0.\n"
"To use the current system time, call `touch` with no "
"arguments",
aFile->HumanReadablePath().get()));
}
nsresult rv = aFile->SetLastModifiedTime(now);
if (NS_FAILED(rv)) {
IOError err(rv);
if (IsFileNotFound(rv)) {
return Err(
err.WithMessage("Could not touch file(%s) because it does not exist",
aFile->HumanReadablePath().get()));
}
return Err(err);
}
return now;
}
/* static */
Result<nsTArray<nsString>, IOUtils::IOError> IOUtils::GetChildrenSync(
nsIFile* aFile) {
MOZ_ASSERT(!NS_IsMainThread());
nsCOMPtr<nsIDirectoryEnumerator> iter;
nsresult rv = aFile->GetDirectoryEntries(getter_AddRefs(iter));
if (NS_FAILED(rv)) {
IOError err(rv);
if (IsFileNotFound(rv)) {
return Err(err.WithMessage(
"Could not get children of file(%s) because it does not exist",
aFile->HumanReadablePath().get()));
}
if (IsNotDirectory(rv)) {
return Err(err.WithMessage(
"Could not get children of file(%s) because it is not a directory",
aFile->HumanReadablePath().get()));
}
return Err(err);
}
nsTArray<nsString> children;
bool hasMoreElements = false;
MOZ_TRY(iter->HasMoreElements(&hasMoreElements));
while (hasMoreElements) {
nsCOMPtr<nsIFile> child;
MOZ_TRY(iter->GetNextFile(getter_AddRefs(child)));
if (child) {
nsString path;
MOZ_TRY(child->GetPath(path));
children.AppendElement(path);
}
MOZ_TRY(iter->HasMoreElements(&hasMoreElements));
}
return children;
}
/* static */
Result<Ok, IOUtils::IOError> IOUtils::SetPermissionsSync(
nsIFile* aFile, const uint32_t aPermissions) {
MOZ_ASSERT(!NS_IsMainThread());
MOZ_TRY(aFile->SetPermissions(aPermissions));
return Ok{};
}
/* static */
Result<bool, IOUtils::IOError> IOUtils::ExistsSync(nsIFile* aFile) {
MOZ_ASSERT(!NS_IsMainThread());
bool exists = false;
MOZ_TRY(aFile->Exists(&exists));
return exists;
}
/* static */
void IOUtils::GetProfileBeforeChange(GlobalObject& aGlobal,
JS::MutableHandle<JS::Value> aClient,
ErrorResult& aRv) {
MOZ_RELEASE_ASSERT(XRE_IsParentProcess());
MOZ_RELEASE_ASSERT(NS_IsMainThread());
if (auto state = GetState()) {
MOZ_RELEASE_ASSERT(state.ref()->mBlockerStatus !=
ShutdownBlockerStatus::Uninitialized);
if (state.ref()->mBlockerStatus == ShutdownBlockerStatus::Failed) {
aRv.ThrowAbortError("IOUtils: could not register shutdown blockers");
return;
}
MOZ_RELEASE_ASSERT(state.ref()->mBlockerStatus ==
ShutdownBlockerStatus::Initialized);
auto result = state.ref()->mEventQueue->GetProfileBeforeChangeClient();
if (result.isErr()) {
aRv.ThrowAbortError("IOUtils: could not get shutdown client");
return;
}
RefPtr<nsIAsyncShutdownClient> client = result.unwrap();
MOZ_RELEASE_ASSERT(client);
if (nsresult rv = client->GetJsclient(aClient); NS_FAILED(rv)) {
aRv.ThrowAbortError("IOUtils: Could not get shutdown jsclient");
}
return;
}
aRv.ThrowAbortError(
"IOUtils: profileBeforeChange phase has already finished");
}
/* sstatic */
Maybe<IOUtils::StateMutex::AutoLock> IOUtils::GetState() {
auto state = sState.Lock();
if (state->mQueueStatus == EventQueueStatus::Shutdown) {
return Nothing{};
}
if (state->mQueueStatus == EventQueueStatus::Uninitialized) {
MOZ_RELEASE_ASSERT(!state->mEventQueue);
state->mEventQueue = new EventQueue();
state->mQueueStatus = EventQueueStatus::Initialized;
MOZ_RELEASE_ASSERT(state->mBlockerStatus ==
ShutdownBlockerStatus::Uninitialized);
}
if (NS_IsMainThread() &&
state->mBlockerStatus == ShutdownBlockerStatus::Uninitialized) {
state->SetShutdownHooks();
}
return Some(std::move(state));
}
IOUtils::EventQueue::EventQueue() {
MOZ_ALWAYS_SUCCEEDS(NS_CreateBackgroundTaskQueue(
"IOUtils::EventQueue", getter_AddRefs(mBackgroundEventTarget)));
MOZ_RELEASE_ASSERT(mBackgroundEventTarget);
}
void IOUtils::State::SetShutdownHooks() {
if (mBlockerStatus != ShutdownBlockerStatus::Uninitialized) {
return;
}
if (NS_WARN_IF(NS_FAILED(mEventQueue->SetShutdownHooks()))) {
mBlockerStatus = ShutdownBlockerStatus::Failed;
} else {
mBlockerStatus = ShutdownBlockerStatus::Initialized;
}
if (mBlockerStatus != ShutdownBlockerStatus::Initialized) {
NS_WARNING("IOUtils: could not register shutdown blockers.");
}
}
nsresult IOUtils::EventQueue::SetShutdownHooks() {
MOZ_RELEASE_ASSERT(NS_IsMainThread());
nsCOMPtr<nsIAsyncShutdownService> svc = services::GetAsyncShutdownService();
if (!svc) {
return NS_ERROR_NOT_AVAILABLE;
}
nsCOMPtr<nsIAsyncShutdownBlocker> blocker = new IOUtilsShutdownBlocker(
IOUtilsShutdownBlocker::Phase::ProfileBeforeChange);
nsCOMPtr<nsIAsyncShutdownClient> profileBeforeChange;
MOZ_TRY(svc->GetProfileBeforeChange(getter_AddRefs(profileBeforeChange)));
MOZ_RELEASE_ASSERT(profileBeforeChange);
MOZ_TRY(profileBeforeChange->AddBlocker(
blocker, NS_LITERAL_STRING_FROM_CSTRING(__FILE__), __LINE__,
u"IOUtils::EventQueue::SetShutdownHooks"_ns));
nsCOMPtr<nsIAsyncShutdownClient> xpcomWillShutdown;
MOZ_TRY(svc->GetXpcomWillShutdown(getter_AddRefs(xpcomWillShutdown)));
MOZ_RELEASE_ASSERT(xpcomWillShutdown);
blocker = new IOUtilsShutdownBlocker(
IOUtilsShutdownBlocker::Phase::XpcomWillShutdown);
MOZ_TRY(xpcomWillShutdown->AddBlocker(
blocker, NS_LITERAL_STRING_FROM_CSTRING(__FILE__), __LINE__,
u"IOUtils::EventQueue::SetShutdownHooks"_ns));
MOZ_TRY(svc->MakeBarrier(
u"IOUtils: waiting for profileBeforeChange IO to complete"_ns,
getter_AddRefs(mProfileBeforeChangeBarrier)));
MOZ_RELEASE_ASSERT(mProfileBeforeChangeBarrier);
return NS_OK;
}
template <typename OkT, typename Fn>
RefPtr<IOUtils::IOPromise<OkT>> IOUtils::EventQueue::Dispatch(Fn aFunc) {
MOZ_RELEASE_ASSERT(mBackgroundEventTarget);
return InvokeAsync(
mBackgroundEventTarget, __func__, [func = std::move(aFunc)]() {
Result<OkT, IOError> result = func();
if (result.isErr()) {
return IOPromise<OkT>::CreateAndReject(result.unwrapErr(), __func__);
}
return IOPromise<OkT>::CreateAndResolve(result.unwrap(), __func__);
});
};
Result<already_AddRefed<nsIAsyncShutdownClient>, nsresult>
IOUtils::EventQueue::GetProfileBeforeChangeClient() {
if (!mProfileBeforeChangeBarrier) {
return Err(NS_ERROR_NOT_AVAILABLE);
}
nsCOMPtr<nsIAsyncShutdownClient> profileBeforeChange;
MOZ_TRY(mProfileBeforeChangeBarrier->GetClient(
getter_AddRefs(profileBeforeChange)));
return profileBeforeChange.forget();
}
Result<already_AddRefed<nsIAsyncShutdownBarrier>, nsresult>
IOUtils::EventQueue::GetProfileBeforeChangeBarrier() {
if (!mProfileBeforeChangeBarrier) {
return Err(NS_ERROR_NOT_AVAILABLE);
}
return do_AddRef(mProfileBeforeChangeBarrier);
}
/* static */
Result<nsTArray<uint8_t>, IOUtils::IOError> IOUtils::MozLZ4::Compress(
Span<const uint8_t> aUncompressed) {
nsTArray<uint8_t> result;
size_t worstCaseSize =
Compression::LZ4::maxCompressedSize(aUncompressed.Length()) + HEADER_SIZE;
if (!result.SetCapacity(worstCaseSize, fallible)) {
return Err(IOError(NS_ERROR_OUT_OF_MEMORY)
.WithMessage("Could not allocate buffer to compress data"));
}
result.AppendElements(Span(MAGIC_NUMBER.data(), MAGIC_NUMBER.size()));
std::array<uint8_t, sizeof(uint32_t)> contentSizeBytes{};
LittleEndian::writeUint32(contentSizeBytes.data(), aUncompressed.Length());
result.AppendElements(Span(contentSizeBytes.data(), contentSizeBytes.size()));
if (aUncompressed.Length() == 0) {
// Don't try to compress an empty buffer.
// Just return the correctly formed header.
result.SetLength(HEADER_SIZE);
return result;
}
size_t compressed = Compression::LZ4::compress(
reinterpret_cast<const char*>(aUncompressed.Elements()),
aUncompressed.Length(),
reinterpret_cast<char*>(result.Elements()) + HEADER_SIZE);
if (!compressed) {
return Err(
IOError(NS_ERROR_UNEXPECTED).WithMessage("Could not compress data"));
}
result.SetLength(HEADER_SIZE + compressed);
return result;
}
/* static */
Result<IOUtils::JsBuffer, IOUtils::IOError> IOUtils::MozLZ4::Decompress(
Span<const uint8_t> aFileContents, IOUtils::BufferKind aBufferKind) {
if (aFileContents.LengthBytes() < HEADER_SIZE) {
return Err(
IOError(NS_ERROR_FILE_CORRUPTED)
.WithMessage(
"Could not decompress file because the buffer is too short"));
}
auto header = aFileContents.To(HEADER_SIZE);
if (!std::equal(std::begin(MAGIC_NUMBER), std::end(MAGIC_NUMBER),
std::begin(header))) {
nsCString magicStr;
uint32_t i = 0;
for (; i < header.Length() - 1; ++i) {
magicStr.AppendPrintf("%02X ", header.at(i));
}
magicStr.AppendPrintf("%02X", header.at(i));
return Err(IOError(NS_ERROR_FILE_CORRUPTED)
.WithMessage("Could not decompress file because it has an "
"invalid LZ4 header (wrong magic number: '%s')",
magicStr.get()));
}
size_t numBytes = sizeof(uint32_t);
Span<const uint8_t> sizeBytes = header.Last(numBytes);
uint32_t expectedDecompressedSize =
LittleEndian::readUint32(sizeBytes.data());
if (expectedDecompressedSize == 0) {
return JsBuffer::CreateEmpty(aBufferKind);
}
auto contents = aFileContents.From(HEADER_SIZE);
auto result = JsBuffer::Create(aBufferKind, expectedDecompressedSize);
if (result.isErr()) {
return result.propagateErr();
}
JsBuffer decompressed = result.unwrap();
size_t actualSize = 0;
if (!Compression::LZ4::decompress(
reinterpret_cast<const char*>(contents.Elements()), contents.Length(),
reinterpret_cast<char*>(decompressed.Elements()),
expectedDecompressedSize, &actualSize)) {
return Err(
IOError(NS_ERROR_FILE_CORRUPTED)
.WithMessage(
"Could not decompress file contents, the file may be corrupt"));
}
decompressed.SetLength(actualSize);
return decompressed;
}
NS_IMPL_ISUPPORTS(IOUtilsShutdownBlocker, nsIAsyncShutdownBlocker,
nsIAsyncShutdownCompletionCallback);
NS_IMETHODIMP IOUtilsShutdownBlocker::GetName(nsAString& aName) {
aName = u"IOUtils Blocker ("_ns;
switch (mPhase) {
case Phase::ProfileBeforeChange:
aName.Append(u"profile-before-change"_ns);
break;
case Phase::XpcomWillShutdown:
aName.Append(u"xpcom-will-shutdown"_ns);
break;
default:
MOZ_CRASH("Unknown shutdown phase");
}
aName.Append(')');
return NS_OK;
}
NS_IMETHODIMP IOUtilsShutdownBlocker::BlockShutdown(
nsIAsyncShutdownClient* aBarrierClient) {
using EventQueueStatus = IOUtils::EventQueueStatus;
MOZ_RELEASE_ASSERT(NS_IsMainThread());
nsCOMPtr<nsIAsyncShutdownBarrier> barrier;
{
auto state = IOUtils::sState.Lock();
if (state->mQueueStatus == EventQueueStatus::Shutdown) {
// If the blocker for profile-before-change has already run, then the
// event queue is already torn down and we have nothing to do.
MOZ_RELEASE_ASSERT(mPhase == Phase::XpcomWillShutdown);
MOZ_RELEASE_ASSERT(!state->mEventQueue);
Unused << NS_WARN_IF(NS_FAILED(aBarrierClient->RemoveBlocker(this)));
mParentClient = nullptr;
return NS_OK;
}
MOZ_RELEASE_ASSERT(state->mEventQueue);
mParentClient = aBarrierClient;
barrier =
state->mEventQueue->GetProfileBeforeChangeBarrier().unwrapOr(nullptr);
}
// We cannot barrier->Wait() while holding the mutex because it will lead to
// deadlock.
if (!barrier || NS_WARN_IF(NS_FAILED(barrier->Wait(this)))) {
// If we don't have a barrier, we still need to flush the IOUtils event
// queue and disable task submission.
//
// Likewise, if waiting on the barrier failed, we are going to make our best
// attempt to clean up.
Unused << Done();
}
return NS_OK;
}
NS_IMETHODIMP IOUtilsShutdownBlocker::Done() {
using EventQueueStatus = IOUtils::EventQueueStatus;
MOZ_RELEASE_ASSERT(NS_IsMainThread());
auto state = IOUtils::sState.Lock();
MOZ_RELEASE_ASSERT(state->mEventQueue);
// This method is called once we have served all shutdown clients. Now we
// flush the remaining IO queue and forbid additional IO requests.
state->mEventQueue->Dispatch<Ok>([]() { return Ok{}; })
->Then(GetMainThreadSerialEventTarget(), __func__,
[self = RefPtr(this)]() {
if (self->mParentClient) {
Unused << NS_WARN_IF(
NS_FAILED(self->mParentClient->RemoveBlocker(self)));
self->mParentClient = nullptr;
auto state = IOUtils::sState.Lock();
MOZ_RELEASE_ASSERT(state->mEventQueue);
state->mEventQueue = nullptr;
}
});
MOZ_RELEASE_ASSERT(state->mQueueStatus == EventQueueStatus::Initialized);
state->mQueueStatus = EventQueueStatus::Shutdown;
return NS_OK;
}
NS_IMETHODIMP IOUtilsShutdownBlocker::GetState(nsIPropertyBag** aState) {
return NS_OK;
}
Result<IOUtils::InternalWriteOpts, IOUtils::IOError>
IOUtils::InternalWriteOpts::FromBinding(const WriteOptions& aOptions) {
InternalWriteOpts opts;
opts.mFlush = aOptions.mFlush;
opts.mMode = aOptions.mMode;
if (aOptions.mBackupFile.WasPassed()) {
opts.mBackupFile = new nsLocalFile();
if (nsresult rv =
opts.mBackupFile->InitWithPath(aOptions.mBackupFile.Value());
NS_FAILED(rv)) {
return Err(IOUtils::IOError(rv).WithMessage(
"Could not parse path of backupFile (%s)",
NS_ConvertUTF16toUTF8(aOptions.mBackupFile.Value()).get()));
}
}
if (aOptions.mTmpPath.WasPassed()) {
opts.mTmpFile = new nsLocalFile();
if (nsresult rv = opts.mTmpFile->InitWithPath(aOptions.mTmpPath.Value());
NS_FAILED(rv)) {
return Err(IOUtils::IOError(rv).WithMessage(
"Could not parse path of temp file (%s)",
NS_ConvertUTF16toUTF8(aOptions.mTmpPath.Value()).get()));
}
}
opts.mCompress = aOptions.mCompress;
return opts;
}
/* static */
Result<IOUtils::JsBuffer, IOUtils::IOError> IOUtils::JsBuffer::Create(
IOUtils::BufferKind aBufferKind, size_t aCapacity) {
JsBuffer buffer(aBufferKind, aCapacity);
if (aCapacity != 0 && !buffer.mBuffer) {
return Err(IOError(NS_ERROR_OUT_OF_MEMORY)
.WithMessage("Could not allocate buffer"));
}
return buffer;
}
/* static */
IOUtils::JsBuffer IOUtils::JsBuffer::CreateEmpty(
IOUtils::BufferKind aBufferKind) {
JsBuffer buffer(aBufferKind, 0);
MOZ_RELEASE_ASSERT(buffer.mBuffer == nullptr);
return buffer;
}
IOUtils::JsBuffer::JsBuffer(IOUtils::BufferKind aBufferKind, size_t aCapacity)
: mBufferKind(aBufferKind), mCapacity(aCapacity), mLength(0) {
if (mCapacity) {
if (aBufferKind == BufferKind::String) {
mBuffer = JS::UniqueChars(
js_pod_arena_malloc<char>(js::StringBufferArena, mCapacity));
} else {
MOZ_RELEASE_ASSERT(aBufferKind == BufferKind::Uint8Array);
mBuffer = JS::UniqueChars(
js_pod_arena_malloc<char>(js::ArrayBufferContentsArena, mCapacity));
}
}
}
IOUtils::JsBuffer::JsBuffer(IOUtils::JsBuffer&& aOther) noexcept
: mBufferKind(aOther.mBufferKind),
mCapacity(aOther.mCapacity),
mLength(aOther.mLength),
mBuffer(std::move(aOther.mBuffer)) {
aOther.mCapacity = 0;
aOther.mLength = 0;
}
IOUtils::JsBuffer& IOUtils::JsBuffer::operator=(
IOUtils::JsBuffer&& aOther) noexcept {
mBufferKind = aOther.mBufferKind;
mCapacity = aOther.mCapacity;
mLength = aOther.mLength;
mBuffer = std::move(aOther.mBuffer);
// Invalidate aOther.
aOther.mCapacity = 0;
aOther.mLength = 0;
return *this;
}
/* static */
JSString* IOUtils::JsBuffer::IntoString(JSContext* aCx, JsBuffer aBuffer) {
MOZ_RELEASE_ASSERT(aBuffer.mBufferKind == IOUtils::BufferKind::String);
if (!aBuffer.mCapacity) {
return JS_GetEmptyString(aCx);
}
if (IsAscii(aBuffer.BeginReading())) {
// If the string is just plain ASCII, then we can hand the buffer off to
// JavaScript as a Latin1 string (since ASCII is a subset of Latin1).
JS::UniqueLatin1Chars asLatin1(
reinterpret_cast<JS::Latin1Char*>(aBuffer.mBuffer.release()));
return JS_NewLatin1String(aCx, std::move(asLatin1), aBuffer.mLength);
}
// If the string is encodable as Latin1, we need to deflate the string to a
// Latin1 string to accoutn for UTF-8 characters that are encoded as more than
// a single byte.
//
// Otherwise, the string contains characters outside Latin1 so we have to
// inflate to UTF-16.
return JS_NewStringCopyUTF8N(
aCx, JS::UTF8Chars(aBuffer.mBuffer.get(), aBuffer.mLength));
}
/* static */
JSObject* IOUtils::JsBuffer::IntoUint8Array(JSContext* aCx, JsBuffer aBuffer) {
MOZ_RELEASE_ASSERT(aBuffer.mBufferKind == IOUtils::BufferKind::Uint8Array);
if (!aBuffer.mCapacity) {
return JS_NewUint8Array(aCx, 0);
}
char* rawBuffer = aBuffer.mBuffer.release();
MOZ_RELEASE_ASSERT(rawBuffer);
JS::Rooted<JSObject*> arrayBuffer(
aCx, JS::NewArrayBufferWithContents(aCx, aBuffer.mLength,
reinterpret_cast<void*>(rawBuffer)));
if (!arrayBuffer) {
// The array buffer does not take ownership of the data pointer unless
// creation succeeds. We are still on the hook to free it.
//
// aBuffer will be destructed at end of scope, but its destructor does not
// take into account |mCapacity| or |mLength|, so it is OK for them to be
// non-zero here with a null |mBuffer|.
js_free(rawBuffer);
return nullptr;
}
return JS_NewUint8ArrayWithBuffer(aCx, arrayBuffer, 0, aBuffer.mLength);
}
[[nodiscard]] bool ToJSValue(JSContext* aCx, IOUtils::JsBuffer&& aBuffer,
JS::MutableHandle<JS::Value> aValue) {
if (aBuffer.mBufferKind == IOUtils::BufferKind::String) {
JSString* str = IOUtils::JsBuffer::IntoString(aCx, std::move(aBuffer));
if (!str) {
return false;
}
aValue.setString(str);
return true;
}
JSObject* array = IOUtils::JsBuffer::IntoUint8Array(aCx, std::move(aBuffer));
if (!array) {
return false;
}
aValue.setObject(*array);
return true;
}
} // namespace mozilla::dom
#undef REJECT_IF_INIT_PATH_FAILED