The Tor Browser: netwerk/base/src/nsFileStreams.cpp@b8a032363ba2 (annotated)

netwerk/base/src/nsFileStreams.cpp@b8a032363ba2 (annotated)

netwerk/base/src/nsFileStreams.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- 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>
 #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 "nsNetCID.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;
 ////////////////////////////////////////////////////////////////////////////////
 // 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;
 }
 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();
     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;
     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 = 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 (mBehaviorFlags & DELETE_ON_CLOSE) {
         // 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);
     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)
 {
     nsresult rv = DoPendingOpen();
     NS_ENSURE_SUCCESS(rv, rv);
     if (!mLineBuffer) {
       mLineBuffer = new nsLineBuffer<char>;
     }
     return NS_ReadLine(this, mLineBuffer.get(), aLine, aResult);
 }
 NS_IMETHODIMP
 nsFileInputStream::Seek(int32_t aWhence, int64_t aOffset)
 {
     nsresult rv = DoPendingOpen();
     NS_ENSURE_SUCCESS(rv, rv);
     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 (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;
     } else {
         NS_WARNING("This file has not been opened (or could not be opened). "
                    "Sending an invalid file descriptor to the other process!");
     }
     int32_t behaviorFlags = mBehaviorFlags;
     // The other process shouldn't close when it reads the end because it will
     // not be able to reopen the file later.
     behaviorFlags &= ~nsIFileInputStream::CLOSE_ON_EOF;
     // The other process will not be able to reopen the file so transferring
     // this flag is meaningless.
     behaviorFlags &= ~nsIFileInputStream::REOPEN_ON_REWIND;
     // The other process 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_WARN_IF_FALSE(fd.IsValid(), "Received an invalid file descriptor!");
     } else {
         NS_WARNING("Received a bad file descriptor index!");
     }
     if (fd.IsValid()) {
         PRFileDesc* fileDesc = PR_ImportFile(PROsfd(fd.PlatformHandle()));
         if (!fileDesc) {
             NS_WARNING("Failed to import file handle!");
             return false;
         }
         mFD = fileDesc;
     }
     mBehaviorFlags = params.behaviorFlags();
     mIOFlags = params.ioFlags();
     return true;
 }
 ////////////////////////////////////////////////////////////////////////////////
 // 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);
     NS_ENSURE_SUCCESS(rv, rv);
     return nsFileInputStream::Seek(NS_SEEK_SET, mStart);
 }
 NS_IMETHODIMP
 nsPartialFileInputStream::Tell(int64_t *aResult)
 {
     int64_t tell = 0;
     nsresult rv = nsFileInputStream::Tell(&tell);
     if (NS_SUCCEEDED(rv)) {
         *aResult = tell - mStart;
     }
     return rv;
 }
 NS_IMETHODIMP
 nsPartialFileInputStream::Available(uint64_t* aResult)
 {
     uint64_t available = 0;
     nsresult rv = nsFileInputStream::Available(&available);
     if (NS_SUCCEEDED(rv)) {
         *aResult = TruncateSize(available);
     }
     return rv;
 }
 NS_IMETHODIMP
 nsPartialFileInputStream::Read(char* aBuf, uint32_t aCount, uint32_t* aResult)
 {
     uint32_t readsize = (uint32_t) TruncateSize(aCount);
     if (readsize == 0 && mBehaviorFlags & CLOSE_ON_EOF) {
         Close();
         *aResult = 0;
         return NS_OK;
     }
     nsresult rv = nsFileInputStream::Read(aBuf, readsize, aResult);
     if (NS_SUCCEEDED(rv)) {
         mPosition += readsize;
     }
     return rv;
 }
 NS_IMETHODIMP
 nsPartialFileInputStream::Seek(int32_t aWhence, int64_t aOffset)
 {
     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;
     }
     nsresult rv = nsFileInputStream::Seek(NS_SEEK_SET, offset);
     if (NS_SUCCEEDED(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));
 }
 ////////////////////////////////////////////////////////////////////////////////
 // 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);
 }
 ////////////////////////////////////////////////////////////////////////////////
 // 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)
 {
     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);
     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.
         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_ERROR("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);
 }
 ////////////////////////////////////////////////////////////////////////////////

The Tor Browser / annotate

netwerk/base/src/nsFileStreams.cpp@b8a032363ba2 (annotated)

netwerk/base/src/nsFileStreams.cpp