gecko-dev/xpcom/io/nsStringStream.cpp

592 строки
16 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/. */
/**
* Based on original code from nsIStringStream.cpp
*/
#include "ipc/IPCMessageUtils.h"
#include "nsStringStream.h"
#include "nsStreamUtils.h"
#include "nsReadableUtils.h"
#include "nsICloneableInputStream.h"
#include "nsISeekableStream.h"
#include "nsISupportsPrimitives.h"
#include "nsCRT.h"
#include "prerror.h"
#include "nsIClassInfoImpl.h"
#include "mozilla/Attributes.h"
#include "mozilla/ipc/InputStreamUtils.h"
#include "mozilla/Maybe.h"
#include "mozilla/ReentrantMonitor.h"
#include "mozilla/StreamBufferSourceImpl.h"
#include "nsIIPCSerializableInputStream.h"
#include "XPCOMModule.h"
using namespace mozilla::ipc;
using mozilla::fallible;
using mozilla::MakeRefPtr;
using mozilla::MallocSizeOf;
using mozilla::nsBorrowedSource;
using mozilla::nsCStringSource;
using mozilla::nsTArraySource;
using mozilla::ReentrantMonitorAutoEnter;
using mozilla::Span;
using mozilla::StreamBufferSource;
//-----------------------------------------------------------------------------
// nsIStringInputStream implementation
//-----------------------------------------------------------------------------
class nsStringInputStream final : public nsIStringInputStream,
public nsISeekableStream,
public nsISupportsCString,
public nsIIPCSerializableInputStream,
public nsICloneableInputStream {
public:
NS_DECL_THREADSAFE_ISUPPORTS
NS_DECL_NSIINPUTSTREAM
NS_DECL_NSISTRINGINPUTSTREAM
NS_DECL_NSISEEKABLESTREAM
NS_DECL_NSITELLABLESTREAM
NS_DECL_NSISUPPORTSPRIMITIVE
NS_DECL_NSISUPPORTSCSTRING
NS_DECL_NSIIPCSERIALIZABLEINPUTSTREAM
NS_DECL_NSICLONEABLEINPUTSTREAM
nsStringInputStream() = default;
nsresult Init(nsCString&& aString);
nsresult Init(nsTArray<uint8_t>&& aArray);
private:
~nsStringInputStream() = default;
size_t Length() const MOZ_REQUIRES(mMon) {
return mSource ? mSource->Data().Length() : 0;
}
size_t LengthRemaining() const MOZ_REQUIRES(mMon) {
return Length() - mOffset;
}
void Clear() MOZ_REQUIRES(mMon) { mSource = nullptr; }
bool Closed() MOZ_REQUIRES(mMon) { return !mSource; }
RefPtr<StreamBufferSource> mSource MOZ_GUARDED_BY(mMon);
size_t mOffset MOZ_GUARDED_BY(mMon) = 0;
mutable mozilla::ReentrantMonitor mMon{"nsStringInputStream"};
};
nsresult nsStringInputStream::Init(nsCString&& aString) {
nsCString string;
if (!string.Assign(std::move(aString), fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
auto source = MakeRefPtr<nsCStringSource>(std::move(string));
return SetDataSource(source);
}
nsresult nsStringInputStream::Init(nsTArray<uint8_t>&& aArray) {
auto source = MakeRefPtr<nsTArraySource>(std::move(aArray));
return SetDataSource(source);
}
// This class needs to support threadsafe refcounting since people often
// allocate a string stream, and then read it from a background thread.
NS_IMPL_ADDREF(nsStringInputStream)
NS_IMPL_RELEASE(nsStringInputStream)
NS_IMPL_CLASSINFO(nsStringInputStream, nullptr, nsIClassInfo::THREADSAFE,
NS_STRINGINPUTSTREAM_CID)
NS_IMPL_QUERY_INTERFACE_CI(nsStringInputStream, nsIStringInputStream,
nsIInputStream, nsISupportsCString,
nsISeekableStream, nsITellableStream,
nsIIPCSerializableInputStream,
nsICloneableInputStream)
NS_IMPL_CI_INTERFACE_GETTER(nsStringInputStream, nsIStringInputStream,
nsIInputStream, nsISupportsCString,
nsISeekableStream, nsITellableStream,
nsICloneableInputStream)
/////////
// nsISupportsCString implementation
/////////
NS_IMETHODIMP
nsStringInputStream::GetType(uint16_t* aType) {
*aType = TYPE_CSTRING;
return NS_OK;
}
NS_IMETHODIMP
nsStringInputStream::GetData(nsACString& data) {
ReentrantMonitorAutoEnter lock(mMon);
// The stream doesn't have any data when it is closed. We could fake it
// and return an empty string here, but it seems better to keep this return
// value consistent with the behavior of the other 'getter' methods.
if (NS_WARN_IF(Closed())) {
return NS_BASE_STREAM_CLOSED;
}
return mSource->GetData(data);
}
NS_IMETHODIMP
nsStringInputStream::SetData(const nsACString& aData) {
nsCString string;
if (!string.Assign(aData, fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
auto source = MakeRefPtr<nsCStringSource>(std::move(string));
return SetDataSource(source);
}
NS_IMETHODIMP
nsStringInputStream::ToString(char** aResult) {
// NOTE: This method may result in data loss, so we do not implement it.
return NS_ERROR_NOT_IMPLEMENTED;
}
/////////
// nsIStringInputStream implementation
/////////
NS_IMETHODIMP
nsStringInputStream::SetData(const char* aData, int32_t aDataLen) {
if (NS_WARN_IF(!aData)) {
return NS_ERROR_INVALID_ARG;
}
nsCString string;
if (NS_WARN_IF(!string.Assign(aData, aDataLen, fallible))) {
return NS_ERROR_OUT_OF_MEMORY;
}
auto source = MakeRefPtr<nsCStringSource>(std::move(string));
return SetDataSource(source);
}
NS_IMETHODIMP
nsStringInputStream::SetUTF8Data(const nsACString& aData) {
return nsStringInputStream::SetData(aData);
}
NS_IMETHODIMP
nsStringInputStream::AdoptData(char* aData, int32_t aDataLen) {
if (NS_WARN_IF(!aData)) {
return NS_ERROR_INVALID_ARG;
}
nsCString string;
string.Adopt(aData, aDataLen);
auto source = MakeRefPtr<nsCStringSource>(std::move(string));
return SetDataSource(source);
}
NS_IMETHODIMP
nsStringInputStream::ShareData(const char* aData, int32_t aDataLen) {
if (NS_WARN_IF(!aData)) {
return NS_ERROR_INVALID_ARG;
}
size_t length = aDataLen < 0 ? strlen(aData) : size_t(aDataLen);
auto source = MakeRefPtr<nsBorrowedSource>(Span{aData, length});
return SetDataSource(source);
}
NS_IMETHODIMP
nsStringInputStream::SetDataSource(StreamBufferSource* aSource) {
ReentrantMonitorAutoEnter lock(mMon);
if (NS_WARN_IF(!aSource)) {
return NS_ERROR_INVALID_ARG;
}
mSource = aSource;
mOffset = 0;
return NS_OK;
}
NS_IMETHODIMP_(size_t)
nsStringInputStream::SizeOfIncludingThisIfUnshared(MallocSizeOf aMallocSizeOf) {
ReentrantMonitorAutoEnter lock(mMon);
size_t n = aMallocSizeOf(this);
if (mSource) {
n += mSource->SizeOfIncludingThisIfUnshared(aMallocSizeOf);
}
return n;
}
NS_IMETHODIMP_(size_t)
nsStringInputStream::SizeOfIncludingThisEvenIfShared(
MallocSizeOf aMallocSizeOf) {
ReentrantMonitorAutoEnter lock(mMon);
size_t n = aMallocSizeOf(this);
if (mSource) {
n += mSource->SizeOfIncludingThisEvenIfShared(aMallocSizeOf);
}
return n;
}
/////////
// nsIInputStream implementation
/////////
NS_IMETHODIMP
nsStringInputStream::Close() {
ReentrantMonitorAutoEnter lock(mMon);
Clear();
return NS_OK;
}
NS_IMETHODIMP
nsStringInputStream::Available(uint64_t* aLength) {
ReentrantMonitorAutoEnter lock(mMon);
NS_ASSERTION(aLength, "null ptr");
if (Closed()) {
return NS_BASE_STREAM_CLOSED;
}
*aLength = LengthRemaining();
return NS_OK;
}
NS_IMETHODIMP
nsStringInputStream::StreamStatus() {
ReentrantMonitorAutoEnter lock(mMon);
return Closed() ? NS_BASE_STREAM_CLOSED : NS_OK;
}
NS_IMETHODIMP
nsStringInputStream::Read(char* aBuf, uint32_t aCount, uint32_t* aReadCount) {
NS_ASSERTION(aBuf, "null ptr");
return ReadSegments(NS_CopySegmentToBuffer, aBuf, aCount, aReadCount);
}
NS_IMETHODIMP
nsStringInputStream::ReadSegments(nsWriteSegmentFun aWriter, void* aClosure,
uint32_t aCount, uint32_t* aResult) {
ReentrantMonitorAutoEnter lock(mMon);
NS_ASSERTION(aResult, "null ptr");
NS_ASSERTION(Length() >= mOffset, "bad stream state");
if (Closed()) {
return NS_BASE_STREAM_CLOSED;
}
// We may be at end-of-file
size_t maxCount = LengthRemaining();
if (maxCount == 0) {
*aResult = 0;
return NS_OK;
}
if (aCount > maxCount) {
aCount = maxCount;
}
RefPtr<StreamBufferSource> source = mSource;
size_t offset = mOffset;
nsresult rv = aWriter(this, aClosure, source->Data().Elements() + offset, 0,
aCount, aResult);
if (Closed()) {
NS_WARNING("nsStringInputStream was closed during ReadSegments");
return NS_OK;
}
MOZ_RELEASE_ASSERT(mSource == source, "String was replaced!");
MOZ_RELEASE_ASSERT(mOffset == offset, "Nested read operation!");
if (NS_SUCCEEDED(rv)) {
NS_ASSERTION(*aResult <= aCount,
"writer should not write more than we asked it to write");
mOffset = offset + *aResult;
}
// errors returned from the writer end here!
return NS_OK;
}
NS_IMETHODIMP
nsStringInputStream::IsNonBlocking(bool* aNonBlocking) {
*aNonBlocking = true;
return NS_OK;
}
/////////
// nsISeekableStream implementation
/////////
NS_IMETHODIMP
nsStringInputStream::Seek(int32_t aWhence, int64_t aOffset) {
ReentrantMonitorAutoEnter lock(mMon);
if (Closed()) {
return NS_BASE_STREAM_CLOSED;
}
// Compute new stream position. The given offset may be a negative value.
int64_t newPos = aOffset;
switch (aWhence) {
case NS_SEEK_SET:
break;
case NS_SEEK_CUR:
newPos += (int64_t)mOffset;
break;
case NS_SEEK_END:
newPos += (int64_t)Length();
break;
default:
NS_ERROR("invalid aWhence");
return NS_ERROR_INVALID_ARG;
}
if (NS_WARN_IF(newPos < 0) || NS_WARN_IF(newPos > (int64_t)Length())) {
return NS_ERROR_INVALID_ARG;
}
mOffset = (size_t)newPos;
return NS_OK;
}
NS_IMETHODIMP
nsStringInputStream::SetEOF() {
ReentrantMonitorAutoEnter lock(mMon);
if (Closed()) {
return NS_BASE_STREAM_CLOSED;
}
mOffset = Length();
return NS_OK;
}
/////////
// nsITellableStream implementation
/////////
NS_IMETHODIMP
nsStringInputStream::Tell(int64_t* aOutWhere) {
ReentrantMonitorAutoEnter lock(mMon);
if (Closed()) {
return NS_BASE_STREAM_CLOSED;
}
*aOutWhere = (int64_t)mOffset;
return NS_OK;
}
/////////
// nsIIPCSerializableInputStream implementation
/////////
void nsStringInputStream::SerializedComplexity(uint32_t aMaxSize,
uint32_t* aSizeUsed,
uint32_t* aPipes,
uint32_t* aTransferables) {
ReentrantMonitorAutoEnter lock(mMon);
if (Length() >= aMaxSize) {
*aPipes = 1;
} else {
*aSizeUsed = Length();
}
}
void nsStringInputStream::Serialize(InputStreamParams& aParams,
uint32_t aMaxSize, uint32_t* aSizeUsed) {
ReentrantMonitorAutoEnter lock(mMon);
MOZ_DIAGNOSTIC_ASSERT(!Closed(), "cannot send a closed stream!");
MOZ_ASSERT(aSizeUsed);
*aSizeUsed = 0;
if (Length() >= aMaxSize) {
// If the input stream is non-owning (i.e. it was initialized with
// `ShareData`), create a new owning source so that it doesn't go away while
// async copying.
if (!mSource->Owning()) {
auto source =
MakeRefPtr<nsCStringSource>(nsDependentCSubstring(mSource->Data()));
mSource = source;
}
InputStreamHelper::SerializeInputStreamAsPipe(this, aParams);
return;
}
*aSizeUsed = Length();
StringInputStreamParams params;
mSource->GetData(params.data());
aParams = params;
}
bool nsStringInputStream::Deserialize(const InputStreamParams& aParams) {
if (aParams.type() != InputStreamParams::TStringInputStreamParams) {
NS_ERROR("Received unknown parameters from the other process!");
return false;
}
const StringInputStreamParams& params = aParams.get_StringInputStreamParams();
if (NS_FAILED(SetData(params.data()))) {
NS_WARNING("SetData failed!");
return false;
}
return true;
}
/////////
// nsICloneableInputStream implementation
/////////
NS_IMETHODIMP
nsStringInputStream::GetCloneable(bool* aCloneableOut) {
*aCloneableOut = true;
return NS_OK;
}
NS_IMETHODIMP
nsStringInputStream::Clone(nsIInputStream** aCloneOut) {
ReentrantMonitorAutoEnter lock(mMon);
RefPtr<nsStringInputStream> ref = new nsStringInputStream();
// Nothing else can access this yet, but suppress static analysis warnings
ReentrantMonitorAutoEnter reflock(ref->mMon);
if (mSource && !mSource->Owning()) {
auto data = mSource->Data();
nsresult rv = ref->SetData(data.Elements(), data.Length());
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
} else {
ref->mSource = mSource;
}
// mOffset is overwritten by SetData().
ref->mOffset = mOffset;
ref.forget(aCloneOut);
return NS_OK;
}
nsresult NS_NewByteInputStream(nsIInputStream** aStreamResult,
mozilla::Span<const char> aStringToRead,
nsAssignmentType aAssignment) {
MOZ_ASSERT(aStreamResult, "null out ptr");
RefPtr<nsStringInputStream> stream = new nsStringInputStream();
nsresult rv;
switch (aAssignment) {
case NS_ASSIGNMENT_COPY:
rv = stream->SetData(aStringToRead.Elements(), aStringToRead.Length());
break;
case NS_ASSIGNMENT_DEPEND:
rv = stream->ShareData(aStringToRead.Elements(), aStringToRead.Length());
break;
case NS_ASSIGNMENT_ADOPT:
rv = stream->AdoptData(const_cast<char*>(aStringToRead.Elements()),
aStringToRead.Length());
break;
default:
NS_ERROR("invalid assignment type");
rv = NS_ERROR_INVALID_ARG;
}
if (NS_FAILED(rv)) {
return rv;
}
stream.forget(aStreamResult);
return NS_OK;
}
nsresult NS_NewByteInputStream(nsIInputStream** aStreamResult,
nsTArray<uint8_t>&& aArray) {
MOZ_ASSERT(aStreamResult, "null out ptr");
RefPtr<nsStringInputStream> stream = new nsStringInputStream();
nsresult rv = stream->Init(std::move(aArray));
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
stream.forget(aStreamResult);
return NS_OK;
}
extern nsresult NS_NewByteInputStream(nsIInputStream** aStreamResult,
mozilla::StreamBufferSource* aSource) {
MOZ_ASSERT(aStreamResult, "null out ptr");
RefPtr<nsStringInputStream> stream = new nsStringInputStream();
nsresult rv = stream->SetDataSource(aSource);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
stream.forget(aStreamResult);
return NS_OK;
}
nsresult NS_NewCStringInputStream(nsIInputStream** aStreamResult,
const nsACString& aStringToRead) {
MOZ_ASSERT(aStreamResult, "null out ptr");
RefPtr<nsStringInputStream> stream = new nsStringInputStream();
nsresult rv = stream->SetData(aStringToRead);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
stream.forget(aStreamResult);
return NS_OK;
}
nsresult NS_NewCStringInputStream(nsIInputStream** aStreamResult,
nsCString&& aStringToRead) {
MOZ_ASSERT(aStreamResult, "null out ptr");
RefPtr<nsStringInputStream> stream = new nsStringInputStream();
nsresult rv = stream->Init(std::move(aStringToRead));
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
stream.forget(aStreamResult);
return NS_OK;
}
// factory method for constructing a nsStringInputStream object
nsresult nsStringInputStreamConstructor(REFNSIID aIID, void** aResult) {
*aResult = nullptr;
RefPtr<nsStringInputStream> inst = new nsStringInputStream();
return inst->QueryInterface(aIID, aResult);
}