Add m-esr52 at 52.6.0

1 files changed, 1153 insertions, 0 deletions

diff --git a/netwerk/base/nsFileStreams.cpp b/netwerk/base/nsFileStreams.cpp
new file mode 100644
index 000000000..2ddb7ae98
--- /dev/null
+++ b/netwerk/base/nsFileStreams.cpp
@@ -0,0 +1,1153 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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 "ipc/IPCMessageUtils.h"
+
+#if defined(XP_UNIX) || defined(XP_BEOS)
+#include <unistd.h>
+#elif defined(XP_WIN)
+#include <windows.h>
+#include "nsILocalFileWin.h"
+#else
+// XXX add necessary include file for ftruncate (or equivalent)
+#endif
+
+#include "private/pprio.h"
+
+#include "nsFileStreams.h"
+#include "nsIFile.h"
+#include "nsReadLine.h"
+#include "nsIClassInfoImpl.h"
+#include "mozilla/ipc/InputStreamUtils.h"
+#include "mozilla/Unused.h"
+#include "mozilla/FileUtils.h"
+#include "nsNetCID.h"
+#include "nsXULAppAPI.h"
+
+#define NS_NO_INPUT_BUFFERING 1 // see http://bugzilla.mozilla.org/show_bug.cgi?id=41067
+
+typedef mozilla::ipc::FileDescriptor::PlatformHandleType FileHandleType;
+
+using namespace mozilla::ipc;
+using mozilla::DebugOnly;
+using mozilla::Maybe;
+using mozilla::Nothing;
+using mozilla::Some;
+
+////////////////////////////////////////////////////////////////////////////////
+// nsFileStreamBase
+
+nsFileStreamBase::nsFileStreamBase()
+    : mFD(nullptr)
+    , mBehaviorFlags(0)
+    , mDeferredOpen(false)
+{
+}
+
+nsFileStreamBase::~nsFileStreamBase()
+{
+    Close();
+}
+
+NS_IMPL_ISUPPORTS(nsFileStreamBase,
+                  nsISeekableStream,
+                  nsIFileMetadata)
+
+NS_IMETHODIMP
+nsFileStreamBase::Seek(int32_t whence, int64_t offset)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (mFD == nullptr)
+        return NS_BASE_STREAM_CLOSED;
+
+    int64_t cnt = PR_Seek64(mFD, offset, (PRSeekWhence)whence);
+    if (cnt == int64_t(-1)) {
+        return NS_ErrorAccordingToNSPR();
+    }
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFileStreamBase::Tell(int64_t *result)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (mFD == nullptr)
+        return NS_BASE_STREAM_CLOSED;
+
+    int64_t cnt = PR_Seek64(mFD, 0, PR_SEEK_CUR);
+    if (cnt == int64_t(-1)) {
+        return NS_ErrorAccordingToNSPR();
+    }
+    *result = cnt;
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFileStreamBase::SetEOF()
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (mFD == nullptr)
+        return NS_BASE_STREAM_CLOSED;
+
+#if defined(XP_UNIX) || defined(XP_BEOS)
+    // Some system calls require an EOF offset.
+    int64_t offset;
+    rv = Tell(&offset);
+    if (NS_FAILED(rv)) return rv;
+#endif
+
+#if defined(XP_UNIX) || defined(XP_BEOS)
+    if (ftruncate(PR_FileDesc2NativeHandle(mFD), offset) != 0) {
+        NS_ERROR("ftruncate failed");
+        return NS_ERROR_FAILURE;
+    }
+#elif defined(XP_WIN)
+    if (!SetEndOfFile((HANDLE) PR_FileDesc2NativeHandle(mFD))) {
+        NS_ERROR("SetEndOfFile failed");
+        return NS_ERROR_FAILURE;
+    }
+#else
+    // XXX not implemented
+#endif
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFileStreamBase::GetSize(int64_t* _retval)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (!mFD) {
+        return NS_BASE_STREAM_CLOSED;
+    }
+
+    PRFileInfo64 info;
+    if (PR_GetOpenFileInfo64(mFD, &info) == PR_FAILURE) {
+        return NS_BASE_STREAM_OSERROR;
+    }
+
+    *_retval = int64_t(info.size);
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFileStreamBase::GetLastModified(int64_t* _retval)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (!mFD) {
+        return NS_BASE_STREAM_CLOSED;
+    }
+
+    PRFileInfo64 info;
+    if (PR_GetOpenFileInfo64(mFD, &info) == PR_FAILURE) {
+        return NS_BASE_STREAM_OSERROR;
+    }
+
+    int64_t modTime = int64_t(info.modifyTime);
+    if (modTime == 0) {
+        *_retval = 0;
+    }
+    else {
+        *_retval = modTime / int64_t(PR_USEC_PER_MSEC);
+    }
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFileStreamBase::GetFileDescriptor(PRFileDesc** _retval)
+{
+    nsresult rv = DoPendingOpen();
+    if (NS_WARN_IF(NS_FAILED(rv))) {
+      return rv;
+    }
+
+    if (!mFD) {
+        return NS_BASE_STREAM_CLOSED;
+    }
+
+    *_retval = mFD;
+    return NS_OK;
+}
+
+nsresult
+nsFileStreamBase::Close()
+{
+    CleanUpOpen();
+
+    nsresult rv = NS_OK;
+    if (mFD) {
+        if (PR_Close(mFD) == PR_FAILURE)
+            rv = NS_BASE_STREAM_OSERROR;
+        mFD = nullptr;
+    }
+    return rv;
+}
+
+nsresult
+nsFileStreamBase::Available(uint64_t* aResult)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (!mFD) {
+        return NS_BASE_STREAM_CLOSED;
+    }
+
+    // PR_Available with files over 4GB returns an error, so we have to
+    // use the 64-bit version of PR_Available.
+    int64_t avail = PR_Available64(mFD);
+    if (avail == -1) {
+        return NS_ErrorAccordingToNSPR();
+    }
+
+    // If available is greater than 4GB, return 4GB
+    *aResult = (uint64_t)avail;
+    return NS_OK;
+}
+
+nsresult
+nsFileStreamBase::Read(char* aBuf, uint32_t aCount, uint32_t* aResult)
+{
+    nsresult rv = DoPendingOpen();
+    if (rv == NS_ERROR_FILE_NOT_FOUND) {
+      // Don't warn if this is just a deferred file not found.
+      return rv;
+    }
+
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (!mFD) {
+        *aResult = 0;
+        return NS_OK;
+    }
+
+    int32_t bytesRead = PR_Read(mFD, aBuf, aCount);
+    if (bytesRead == -1) {
+        return NS_ErrorAccordingToNSPR();
+    }
+
+    *aResult = bytesRead;
+    return NS_OK;
+}
+
+nsresult
+nsFileStreamBase::ReadSegments(nsWriteSegmentFun aWriter, void* aClosure,
+                               uint32_t aCount, uint32_t* aResult)
+{
+    // ReadSegments is not implemented because it would be inefficient when
+    // the writer does not consume all data.  If you want to call ReadSegments,
+    // wrap a BufferedInputStream around the file stream.  That will call
+    // Read().
+
+    // If this is ever implemented you might need to modify
+    // nsPartialFileInputStream::ReadSegments
+
+    return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+nsresult
+nsFileStreamBase::IsNonBlocking(bool *aNonBlocking)
+{
+    *aNonBlocking = false;
+    return NS_OK;
+}
+
+nsresult
+nsFileStreamBase::Flush(void)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (mFD == nullptr)
+        return NS_BASE_STREAM_CLOSED;
+
+    int32_t cnt = PR_Sync(mFD);
+    if (cnt == -1) {
+        return NS_ErrorAccordingToNSPR();
+    }
+    return NS_OK;
+}
+
+nsresult
+nsFileStreamBase::Write(const char *buf, uint32_t count, uint32_t *result)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (mFD == nullptr)
+        return NS_BASE_STREAM_CLOSED;
+
+    int32_t cnt = PR_Write(mFD, buf, count);
+    if (cnt == -1) {
+        return NS_ErrorAccordingToNSPR();
+    }
+    *result = cnt;
+    return NS_OK;
+}
+
+nsresult
+nsFileStreamBase::WriteFrom(nsIInputStream *inStr, uint32_t count, uint32_t *_retval)
+{
+    NS_NOTREACHED("WriteFrom (see source comment)");
+    return NS_ERROR_NOT_IMPLEMENTED;
+    // File streams intentionally do not support this method.
+    // If you need something like this, then you should wrap
+    // the file stream using nsIBufferedOutputStream
+}
+
+nsresult
+nsFileStreamBase::WriteSegments(nsReadSegmentFun reader, void * closure, uint32_t count, uint32_t *_retval)
+{
+    return NS_ERROR_NOT_IMPLEMENTED;
+    // File streams intentionally do not support this method.
+    // If you need something like this, then you should wrap
+    // the file stream using nsIBufferedOutputStream
+}
+
+nsresult
+nsFileStreamBase::MaybeOpen(nsIFile* aFile, int32_t aIoFlags,
+                            int32_t aPerm, bool aDeferred)
+{
+    NS_ENSURE_STATE(aFile);
+
+    mOpenParams.ioFlags = aIoFlags;
+    mOpenParams.perm = aPerm;
+
+    if (aDeferred) {
+        // Clone the file, as it may change between now and the deferred open
+        nsCOMPtr<nsIFile> file;
+        nsresult rv = aFile->Clone(getter_AddRefs(file));
+        NS_ENSURE_SUCCESS(rv, rv);
+
+        mOpenParams.localFile = do_QueryInterface(file);
+        NS_ENSURE_TRUE(mOpenParams.localFile, NS_ERROR_UNEXPECTED);
+
+        mDeferredOpen = true;
+        return NS_OK;
+    }
+
+    mOpenParams.localFile = aFile;
+
+    // Following call open() at main thread.
+    // Main thread might be blocked, while open a remote file.
+    return DoOpen();
+}
+
+void
+nsFileStreamBase::CleanUpOpen()
+{
+    mOpenParams.localFile = nullptr;
+    mDeferredOpen = false;
+}
+
+nsresult
+nsFileStreamBase::DoOpen()
+{
+    NS_ASSERTION(!mFD, "Already have a file descriptor!");
+    NS_ASSERTION(mOpenParams.localFile, "Must have a file to open");
+
+    PRFileDesc* fd;
+    nsresult rv;
+
+#ifdef XP_WIN
+    if (mBehaviorFlags & nsIFileInputStream::SHARE_DELETE) {
+      nsCOMPtr<nsILocalFileWin> file = do_QueryInterface(mOpenParams.localFile);
+      MOZ_ASSERT(file);
+
+      rv = file->OpenNSPRFileDescShareDelete(mOpenParams.ioFlags,
+                                             mOpenParams.perm,
+                                             &fd);
+    } else
+#endif // XP_WIN
+    {
+      rv = mOpenParams.localFile->OpenNSPRFileDesc(mOpenParams.ioFlags,
+                                                   mOpenParams.perm,
+                                                   &fd);
+    }
+
+    CleanUpOpen();
+    if (NS_FAILED(rv))
+        return rv;
+    mFD = fd;
+
+    return NS_OK;
+}
+
+nsresult
+nsFileStreamBase::DoPendingOpen()
+{
+    if (!mDeferredOpen) {
+        return NS_OK;
+    }
+
+    return DoOpen();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsFileInputStream
+
+NS_IMPL_ADDREF_INHERITED(nsFileInputStream, nsFileStreamBase)
+NS_IMPL_RELEASE_INHERITED(nsFileInputStream, nsFileStreamBase)
+
+NS_IMPL_CLASSINFO(nsFileInputStream, nullptr, nsIClassInfo::THREADSAFE,
+                  NS_LOCALFILEINPUTSTREAM_CID)
+
+NS_INTERFACE_MAP_BEGIN(nsFileInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsIInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsIFileInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsILineInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsIIPCSerializableInputStream)
+    NS_IMPL_QUERY_CLASSINFO(nsFileInputStream)
+NS_INTERFACE_MAP_END_INHERITING(nsFileStreamBase)
+
+NS_IMPL_CI_INTERFACE_GETTER(nsFileInputStream,
+                            nsIInputStream,
+                            nsIFileInputStream,
+                            nsISeekableStream,
+                            nsILineInputStream)
+
+nsresult
+nsFileInputStream::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult)
+{
+    NS_ENSURE_NO_AGGREGATION(aOuter);
+
+    nsFileInputStream* stream = new nsFileInputStream();
+    if (stream == nullptr)
+        return NS_ERROR_OUT_OF_MEMORY;
+    NS_ADDREF(stream);
+    nsresult rv = stream->QueryInterface(aIID, aResult);
+    NS_RELEASE(stream);
+    return rv;
+}
+
+nsresult
+nsFileInputStream::Open(nsIFile* aFile, int32_t aIOFlags, int32_t aPerm)
+{
+    nsresult rv = NS_OK;
+
+    // If the previous file is open, close it
+    if (mFD) {
+        rv = Close();
+        if (NS_FAILED(rv)) return rv;
+    }
+
+    // Open the file
+    if (aIOFlags == -1)
+        aIOFlags = PR_RDONLY;
+    if (aPerm == -1)
+        aPerm = 0;
+
+    rv = MaybeOpen(aFile, aIOFlags, aPerm,
+                   mBehaviorFlags & nsIFileInputStream::DEFER_OPEN);
+
+    if (NS_FAILED(rv)) return rv;
+
+    // if defer open is set, do not remove the file here.
+    // remove the file while Close() is called.
+    if ((mBehaviorFlags & DELETE_ON_CLOSE) &&
+        !(mBehaviorFlags & nsIFileInputStream::DEFER_OPEN)) {
+      // POSIX compatible filesystems allow a file to be unlinked while a
+      // file descriptor is still referencing the file.  since we've already
+      // opened the file descriptor, we'll try to remove the file.  if that
+      // fails, then we'll just remember the nsIFile and remove it after we
+      // close the file descriptor.
+      rv = aFile->Remove(false);
+      if (NS_SUCCEEDED(rv)) {
+        // No need to remove it later. Clear the flag.
+        mBehaviorFlags &= ~DELETE_ON_CLOSE;
+      }
+    }
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFileInputStream::Init(nsIFile* aFile, int32_t aIOFlags, int32_t aPerm,
+                        int32_t aBehaviorFlags)
+{
+    NS_ENSURE_TRUE(!mFD, NS_ERROR_ALREADY_INITIALIZED);
+    NS_ENSURE_TRUE(!mDeferredOpen, NS_ERROR_ALREADY_INITIALIZED);
+
+    mBehaviorFlags = aBehaviorFlags;
+
+    mFile = aFile;
+    mIOFlags = aIOFlags;
+    mPerm = aPerm;
+
+    return Open(aFile, aIOFlags, aPerm);
+}
+
+NS_IMETHODIMP
+nsFileInputStream::Close()
+{
+    // Get the cache position at the time the file was close. This allows
+    // NS_SEEK_CUR on a closed file that has been opened with
+    // REOPEN_ON_REWIND.
+    if (mBehaviorFlags & REOPEN_ON_REWIND) {
+        // Get actual position. Not one modified by subclasses
+        nsFileStreamBase::Tell(&mCachedPosition);
+    }
+
+    // null out mLineBuffer in case Close() is called again after failing
+    mLineBuffer = nullptr;
+    nsresult rv = nsFileStreamBase::Close();
+    if (NS_FAILED(rv)) return rv;
+    if (mFile && (mBehaviorFlags & DELETE_ON_CLOSE)) {
+        rv = mFile->Remove(false);
+        NS_ASSERTION(NS_SUCCEEDED(rv), "failed to delete file");
+        // If we don't need to save the file for reopening, free it up
+        if (!(mBehaviorFlags & REOPEN_ON_REWIND)) {
+          mFile = nullptr;
+        }
+    }
+    return rv;
+}
+
+NS_IMETHODIMP
+nsFileInputStream::Read(char* aBuf, uint32_t aCount, uint32_t* _retval)
+{
+    nsresult rv = nsFileStreamBase::Read(aBuf, aCount, _retval);
+    if (rv == NS_ERROR_FILE_NOT_FOUND) {
+      // Don't warn if this is a deffered file not found.
+      return rv;
+    }
+
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // Check if we're at the end of file and need to close
+    if (mBehaviorFlags & CLOSE_ON_EOF && *_retval == 0) {
+        Close();
+    }
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsFileInputStream::ReadLine(nsACString& aLine, bool* aResult)
+{
+    if (!mLineBuffer) {
+      mLineBuffer = new nsLineBuffer<char>;
+    }
+    return NS_ReadLine(this, mLineBuffer.get(), aLine, aResult);
+}
+
+NS_IMETHODIMP
+nsFileInputStream::Seek(int32_t aWhence, int64_t aOffset)
+{
+  return SeekInternal(aWhence, aOffset);
+}
+
+nsresult
+nsFileInputStream::SeekInternal(int32_t aWhence, int64_t aOffset, bool aClearBuf)
+{
+    nsresult rv = DoPendingOpen();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    if (aClearBuf) {
+        mLineBuffer = nullptr;
+    }
+    if (!mFD) {
+        if (mBehaviorFlags & REOPEN_ON_REWIND) {
+            rv = Open(mFile, mIOFlags, mPerm);
+            NS_ENSURE_SUCCESS(rv, rv);
+
+            // If the file was closed, and we do a relative seek, use the
+            // position we cached when we closed the file to seek to the right
+            // location.
+            if (aWhence == NS_SEEK_CUR) {
+                aWhence = NS_SEEK_SET;
+                aOffset += mCachedPosition;
+            }
+        } else {
+            return NS_BASE_STREAM_CLOSED;
+        }
+    }
+
+    return nsFileStreamBase::Seek(aWhence, aOffset);
+}
+
+NS_IMETHODIMP
+nsFileInputStream::Tell(int64_t *aResult)
+{
+    return nsFileStreamBase::Tell(aResult);
+}
+
+NS_IMETHODIMP
+nsFileInputStream::Available(uint64_t *aResult)
+{
+    return nsFileStreamBase::Available(aResult);
+}
+
+void
+nsFileInputStream::Serialize(InputStreamParams& aParams,
+                             FileDescriptorArray& aFileDescriptors)
+{
+    FileInputStreamParams params;
+
+    if (NS_SUCCEEDED(DoPendingOpen()) && mFD) {
+        FileHandleType fd = FileHandleType(PR_FileDesc2NativeHandle(mFD));
+        NS_ASSERTION(fd, "This should never be null!");
+
+        DebugOnly<FileDescriptor*> dbgFD = aFileDescriptors.AppendElement(fd);
+        NS_ASSERTION(dbgFD->IsValid(), "Sending an invalid file descriptor!");
+
+        params.fileDescriptorIndex() = aFileDescriptors.Length() - 1;
+
+        Close();
+    } else {
+        NS_WARNING("This file has not been opened (or could not be opened). "
+                   "Sending an invalid file descriptor to the other process!");
+
+        params.fileDescriptorIndex() = UINT32_MAX;
+    }
+
+    int32_t behaviorFlags = mBehaviorFlags;
+
+    // The receiving process (or thread) is going to have an open file
+    // descriptor automatically so transferring this flag is meaningless.
+    behaviorFlags &= ~nsIFileInputStream::DEFER_OPEN;
+
+    params.behaviorFlags() = behaviorFlags;
+    params.ioFlags() = mIOFlags;
+
+    aParams = params;
+}
+
+bool
+nsFileInputStream::Deserialize(const InputStreamParams& aParams,
+                               const FileDescriptorArray& aFileDescriptors)
+{
+    NS_ASSERTION(!mFD, "Already have a file descriptor?!");
+    NS_ASSERTION(!mDeferredOpen, "Deferring open?!");
+    NS_ASSERTION(!mFile, "Should never have a file here!");
+    NS_ASSERTION(!mPerm, "This should always be 0!");
+
+    if (aParams.type() != InputStreamParams::TFileInputStreamParams) {
+        NS_WARNING("Received unknown parameters from the other process!");
+        return false;
+    }
+
+    const FileInputStreamParams& params = aParams.get_FileInputStreamParams();
+
+    uint32_t fileDescriptorIndex = params.fileDescriptorIndex();
+
+    FileDescriptor fd;
+    if (fileDescriptorIndex < aFileDescriptors.Length()) {
+        fd = aFileDescriptors[fileDescriptorIndex];
+        NS_WARNING_ASSERTION(fd.IsValid(),
+                             "Received an invalid file descriptor!");
+    } else {
+        NS_WARNING("Received a bad file descriptor index!");
+    }
+
+    if (fd.IsValid()) {
+        auto rawFD = fd.ClonePlatformHandle();
+        PRFileDesc* fileDesc = PR_ImportFile(PROsfd(rawFD.release()));
+        if (!fileDesc) {
+            NS_WARNING("Failed to import file handle!");
+            return false;
+        }
+        mFD = fileDesc;
+    }
+
+    mBehaviorFlags = params.behaviorFlags();
+
+    if (!XRE_IsParentProcess()) {
+        // A child process shouldn't close when it reads the end because it will
+        // not be able to reopen the file later.
+        mBehaviorFlags &= ~nsIFileInputStream::CLOSE_ON_EOF;
+
+        // A child process will not be able to reopen the file so this flag is
+        // meaningless.
+        mBehaviorFlags &= ~nsIFileInputStream::REOPEN_ON_REWIND;
+    }
+
+    mIOFlags = params.ioFlags();
+
+    return true;
+}
+
+Maybe<uint64_t>
+nsFileInputStream::ExpectedSerializedLength()
+{
+    return Nothing();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsPartialFileInputStream
+
+NS_IMPL_ADDREF_INHERITED(nsPartialFileInputStream, nsFileStreamBase)
+NS_IMPL_RELEASE_INHERITED(nsPartialFileInputStream, nsFileStreamBase)
+
+NS_IMPL_CLASSINFO(nsPartialFileInputStream, nullptr, nsIClassInfo::THREADSAFE,
+                  NS_PARTIALLOCALFILEINPUTSTREAM_CID)
+
+// Don't forward to nsFileInputStream as we don't want to QI to
+// nsIFileInputStream
+NS_INTERFACE_MAP_BEGIN(nsPartialFileInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsIInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsIPartialFileInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsILineInputStream)
+    NS_INTERFACE_MAP_ENTRY(nsIIPCSerializableInputStream)
+    NS_IMPL_QUERY_CLASSINFO(nsPartialFileInputStream)
+NS_INTERFACE_MAP_END_INHERITING(nsFileStreamBase)
+
+NS_IMPL_CI_INTERFACE_GETTER(nsPartialFileInputStream,
+                            nsIInputStream,
+                            nsIPartialFileInputStream,
+                            nsISeekableStream,
+                            nsILineInputStream)
+
+nsresult
+nsPartialFileInputStream::Create(nsISupports *aOuter, REFNSIID aIID,
+                                 void **aResult)
+{
+    NS_ENSURE_NO_AGGREGATION(aOuter);
+
+    nsPartialFileInputStream* stream = new nsPartialFileInputStream();
+
+    NS_ADDREF(stream);
+    nsresult rv = stream->QueryInterface(aIID, aResult);
+    NS_RELEASE(stream);
+    return rv;
+}
+
+NS_IMETHODIMP
+nsPartialFileInputStream::Init(nsIFile* aFile, uint64_t aStart,
+                               uint64_t aLength, int32_t aIOFlags,
+                               int32_t aPerm, int32_t aBehaviorFlags)
+{
+    mStart = aStart;
+    mLength = aLength;
+    mPosition = 0;
+
+    nsresult rv = nsFileInputStream::Init(aFile, aIOFlags, aPerm,
+                                          aBehaviorFlags);
+
+    // aFile is a partial file, it must exist.
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    mDeferredSeek = true;
+
+    return rv;
+}
+
+NS_IMETHODIMP
+nsPartialFileInputStream::Tell(int64_t *aResult)
+{
+    int64_t tell = 0;
+
+    nsresult rv = DoPendingSeek();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = nsFileInputStream::Tell(&tell);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+
+    *aResult = tell - mStart;
+    return rv;
+}
+
+NS_IMETHODIMP
+nsPartialFileInputStream::Available(uint64_t* aResult)
+{
+    uint64_t available = 0;
+
+    nsresult rv = DoPendingSeek();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    rv = nsFileInputStream::Available(&available);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    *aResult = TruncateSize(available);
+    return rv;
+}
+
+NS_IMETHODIMP
+nsPartialFileInputStream::Read(char* aBuf, uint32_t aCount, uint32_t* aResult)
+{
+    nsresult rv = DoPendingSeek();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    uint32_t readsize = (uint32_t) TruncateSize(aCount);
+    if (readsize == 0 && mBehaviorFlags & CLOSE_ON_EOF) {
+        Close();
+        *aResult = 0;
+        return NS_OK;
+    }
+
+    rv = nsFileInputStream::Read(aBuf, readsize, aResult);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    mPosition += readsize;
+    return rv;
+}
+
+NS_IMETHODIMP
+nsPartialFileInputStream::Seek(int32_t aWhence, int64_t aOffset)
+{
+    nsresult rv = DoPendingSeek();
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    int64_t offset;
+    switch (aWhence) {
+        case NS_SEEK_SET:
+            offset = mStart + aOffset;
+            break;
+        case NS_SEEK_CUR:
+            offset = mStart + mPosition + aOffset;
+            break;
+        case NS_SEEK_END:
+            offset = mStart + mLength + aOffset;
+            break;
+        default:
+            return NS_ERROR_ILLEGAL_VALUE;
+    }
+
+    if (offset < (int64_t)mStart || offset > (int64_t)(mStart + mLength)) {
+        return NS_ERROR_INVALID_ARG;
+    }
+
+    rv = nsFileInputStream::Seek(NS_SEEK_SET, offset);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    mPosition = offset - mStart;
+    return rv;
+}
+
+void
+nsPartialFileInputStream::Serialize(InputStreamParams& aParams,
+                                    FileDescriptorArray& aFileDescriptors)
+{
+    // Serialize the base class first.
+    InputStreamParams fileParams;
+    nsFileInputStream::Serialize(fileParams, aFileDescriptors);
+
+    PartialFileInputStreamParams params;
+
+    params.fileStreamParams() = fileParams.get_FileInputStreamParams();
+    params.begin() = mStart;
+    params.length() = mLength;
+
+    aParams = params;
+}
+
+bool
+nsPartialFileInputStream::Deserialize(
+                                    const InputStreamParams& aParams,
+                                    const FileDescriptorArray& aFileDescriptors)
+{
+    NS_ASSERTION(!mFD, "Already have a file descriptor?!");
+    NS_ASSERTION(!mStart, "Already have a start?!");
+    NS_ASSERTION(!mLength, "Already have a length?!");
+    NS_ASSERTION(!mPosition, "Already have a position?!");
+
+    if (aParams.type() != InputStreamParams::TPartialFileInputStreamParams) {
+        NS_WARNING("Received unknown parameters from the other process!");
+        return false;
+    }
+
+    const PartialFileInputStreamParams& params =
+        aParams.get_PartialFileInputStreamParams();
+
+    // Deserialize the base class first.
+    InputStreamParams fileParams(params.fileStreamParams());
+    if (!nsFileInputStream::Deserialize(fileParams, aFileDescriptors)) {
+        NS_WARNING("Base class deserialize failed!");
+        return false;
+    }
+
+    NS_ASSERTION(mFD, "Must have a file descriptor now!");
+
+    mStart = params.begin();
+    mLength = params.length();
+    mPosition = 0;
+
+    if (!mStart) {
+      return true;
+    }
+
+    // XXX This is so broken. Main thread IO alert.
+    return NS_SUCCEEDED(nsFileInputStream::Seek(NS_SEEK_SET, mStart));
+}
+
+Maybe<uint64_t>
+nsPartialFileInputStream::ExpectedSerializedLength()
+{
+    return Some(mLength);
+}
+
+
+nsresult
+nsPartialFileInputStream::DoPendingSeek()
+{
+    if (!mDeferredSeek) {
+       return NS_OK;
+    }
+
+    mDeferredSeek = false;
+
+    // This is the first time to open the file, don't clear mLinebuffer.
+    // mLineBuffer might be already initialized by ReadLine().
+    return nsFileInputStream::SeekInternal(NS_SEEK_SET, mStart, false);
+}
+////////////////////////////////////////////////////////////////////////////////
+// nsFileOutputStream
+
+NS_IMPL_ISUPPORTS_INHERITED(nsFileOutputStream,
+                            nsFileStreamBase,
+                            nsIOutputStream,
+                            nsIFileOutputStream)
+
+nsresult
+nsFileOutputStream::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult)
+{
+    NS_ENSURE_NO_AGGREGATION(aOuter);
+
+    nsFileOutputStream* stream = new nsFileOutputStream();
+    if (stream == nullptr)
+        return NS_ERROR_OUT_OF_MEMORY;
+    NS_ADDREF(stream);
+    nsresult rv = stream->QueryInterface(aIID, aResult);
+    NS_RELEASE(stream);
+    return rv;
+}
+
+NS_IMETHODIMP
+nsFileOutputStream::Init(nsIFile* file, int32_t ioFlags, int32_t perm,
+                         int32_t behaviorFlags)
+{
+    NS_ENSURE_TRUE(mFD == nullptr, NS_ERROR_ALREADY_INITIALIZED);
+    NS_ENSURE_TRUE(!mDeferredOpen, NS_ERROR_ALREADY_INITIALIZED);
+
+    mBehaviorFlags = behaviorFlags;
+
+    if (ioFlags == -1)
+        ioFlags = PR_WRONLY | PR_CREATE_FILE | PR_TRUNCATE;
+    if (perm <= 0)
+        perm = 0664;
+
+    return MaybeOpen(file, ioFlags, perm,
+                     mBehaviorFlags & nsIFileOutputStream::DEFER_OPEN);
+}
+
+NS_IMETHODIMP
+nsFileOutputStream::Preallocate(int64_t aLength)
+{
+    if (!mFD) {
+        return NS_ERROR_NOT_INITIALIZED;
+    }
+
+    if (!mozilla::fallocate(mFD, aLength)) {
+        return NS_ERROR_FAILURE;
+    }
+
+    return NS_OK;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsAtomicFileOutputStream
+
+NS_IMPL_ISUPPORTS_INHERITED(nsAtomicFileOutputStream,
+                            nsFileOutputStream,
+                            nsISafeOutputStream,
+                            nsIOutputStream,
+                            nsIFileOutputStream)
+
+NS_IMETHODIMP
+nsAtomicFileOutputStream::Init(nsIFile* file, int32_t ioFlags, int32_t perm,
+                             int32_t behaviorFlags)
+{
+    // While `PR_APPEND` is not supported, `-1` is used as `ioFlags` parameter
+    // in some places, and `PR_APPEND | PR_TRUNCATE` does not require appending
+    // to existing file. So, throw an exception only if `PR_APPEND` is
+    // explicitly specified without `PR_TRUNCATE`.
+    if ((ioFlags & PR_APPEND) && !(ioFlags & PR_TRUNCATE)) {
+        return NS_ERROR_INVALID_ARG;
+    }
+    return nsFileOutputStream::Init(file, ioFlags, perm, behaviorFlags);
+}
+
+nsresult
+nsAtomicFileOutputStream::DoOpen()
+{
+    // Make sure mOpenParams.localFile will be empty if we bail somewhere in
+    // this function
+    nsCOMPtr<nsIFile> file;
+    file.swap(mOpenParams.localFile);
+
+    if (!file) {
+        return NS_ERROR_NOT_INITIALIZED;
+    }
+    nsresult rv = file->Exists(&mTargetFileExists);
+    if (NS_FAILED(rv)) {
+        NS_ERROR("Can't tell if target file exists");
+        mTargetFileExists = true; // Safer to assume it exists - we just do more work.
+    }
+
+    // follow symlinks, for two reasons:
+    // 1) if a user has deliberately set up a profile file as a symlink, we honor it
+    // 2) to make the MoveToNative() in Finish() an atomic operation (which may not
+    //    be the case if moving across directories on different filesystems).
+    nsCOMPtr<nsIFile> tempResult;
+    rv = file->Clone(getter_AddRefs(tempResult));
+    if (NS_SUCCEEDED(rv)) {
+        tempResult->SetFollowLinks(true);
+
+        // XP_UNIX ignores SetFollowLinks(), so we have to normalize.
+        if (mTargetFileExists) {
+            tempResult->Normalize();
+        }
+    }
+
+    if (NS_SUCCEEDED(rv) && mTargetFileExists) {
+        uint32_t origPerm;
+        if (NS_FAILED(file->GetPermissions(&origPerm))) {
+            NS_ERROR("Can't get permissions of target file");
+            origPerm = mOpenParams.perm;
+        }
+        // XXX What if |perm| is more restrictive then |origPerm|?
+        // This leaves the user supplied permissions as they were.
+        rv = tempResult->CreateUnique(nsIFile::NORMAL_FILE_TYPE, origPerm);
+    }
+    if (NS_SUCCEEDED(rv)) {
+        // nsFileOutputStream::DoOpen will work on the temporary file, so we
+        // prepare it and place it in mOpenParams.localFile.
+        mOpenParams.localFile = tempResult;
+        mTempFile = tempResult;
+        mTargetFile = file;
+        rv = nsFileOutputStream::DoOpen();
+    }
+    return rv;
+}
+
+NS_IMETHODIMP
+nsAtomicFileOutputStream::Close()
+{
+    nsresult rv = nsFileOutputStream::Close();
+
+    // the consumer doesn't want the original file overwritten -
+    // so clean up by removing the temp file.
+    if (mTempFile) {
+        mTempFile->Remove(false);
+        mTempFile = nullptr;
+    }
+
+    return rv;
+}
+
+NS_IMETHODIMP
+nsAtomicFileOutputStream::Finish()
+{
+    nsresult rv = nsFileOutputStream::Close();
+
+    // if there is no temp file, don't try to move it over the original target.
+    // It would destroy the targetfile if close() is called twice.
+    if (!mTempFile)
+        return rv;
+
+    // Only overwrite if everything was ok, and the temp file could be closed.
+    if (NS_SUCCEEDED(mWriteResult) && NS_SUCCEEDED(rv)) {
+        NS_ENSURE_STATE(mTargetFile);
+
+        if (!mTargetFileExists) {
+            // If the target file did not exist when we were initialized, then the
+            // temp file we gave out was actually a reference to the target file.
+            // since we succeeded in writing to the temp file (and hence succeeded
+            // in writing to the target file), there is nothing more to do.
+#ifdef DEBUG
+            bool equal;
+            if (NS_FAILED(mTargetFile->Equals(mTempFile, &equal)) || !equal)
+                NS_WARNING("mTempFile not equal to mTargetFile");
+#endif
+        }
+        else {
+            nsAutoString targetFilename;
+            rv = mTargetFile->GetLeafName(targetFilename);
+            if (NS_SUCCEEDED(rv)) {
+                // This will replace target.
+                rv = mTempFile->MoveTo(nullptr, targetFilename);
+                if (NS_FAILED(rv))
+                    mTempFile->Remove(false);
+            }
+        }
+    }
+    else {
+        mTempFile->Remove(false);
+
+        // if writing failed, propagate the failure code to the caller.
+        if (NS_FAILED(mWriteResult))
+            rv = mWriteResult;
+    }
+    mTempFile = nullptr;
+    return rv;
+}
+
+NS_IMETHODIMP
+nsAtomicFileOutputStream::Write(const char *buf, uint32_t count, uint32_t *result)
+{
+    nsresult rv = nsFileOutputStream::Write(buf, count, result);
+    if (NS_SUCCEEDED(mWriteResult)) {
+        if (NS_FAILED(rv))
+            mWriteResult = rv;
+        else if (count != *result)
+            mWriteResult = NS_ERROR_LOSS_OF_SIGNIFICANT_DATA;
+
+        if (NS_FAILED(mWriteResult) && count > 0)
+            NS_WARNING("writing to output stream failed! data may be lost");
+    }
+    return rv;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsSafeFileOutputStream
+
+NS_IMETHODIMP
+nsSafeFileOutputStream::Finish()
+{
+    (void) Flush();
+    return nsAtomicFileOutputStream::Finish();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsFileStream
+
+NS_IMPL_ISUPPORTS_INHERITED(nsFileStream,
+                            nsFileStreamBase,
+                            nsIInputStream,
+                            nsIOutputStream,
+                            nsIFileStream)
+
+NS_IMETHODIMP
+nsFileStream::Init(nsIFile* file, int32_t ioFlags, int32_t perm,
+                   int32_t behaviorFlags)
+{
+    NS_ENSURE_TRUE(mFD == nullptr, NS_ERROR_ALREADY_INITIALIZED);
+    NS_ENSURE_TRUE(!mDeferredOpen, NS_ERROR_ALREADY_INITIALIZED);
+
+    mBehaviorFlags = behaviorFlags;
+
+    if (ioFlags == -1)
+        ioFlags = PR_RDWR;
+    if (perm <= 0)
+        perm = 0;
+
+    return MaybeOpen(file, ioFlags, perm,
+                     mBehaviorFlags & nsIFileStream::DEFER_OPEN);
+}
+
+////////////////////////////////////////////////////////////////////////////////