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Diffstat (limited to 'netwerk/base/nsIncrementalDownload.cpp')
| -rw-r--r-- | netwerk/base/nsIncrementalDownload.cpp | 873 |
1 files changed, 873 insertions, 0 deletions
diff --git a/netwerk/base/nsIncrementalDownload.cpp b/netwerk/base/nsIncrementalDownload.cpp new file mode 100644 index 0000000000..5ef9ba8fe5 --- /dev/null +++ b/netwerk/base/nsIncrementalDownload.cpp @@ -0,0 +1,873 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim:set ts=2 sw=2 sts=2 et cindent: */ +/* 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 "mozilla/Attributes.h" +#include "mozilla/UniquePtrExtensions.h" +#include "mozilla/UniquePtr.h" + +#include "nsIIncrementalDownload.h" +#include "nsIRequestObserver.h" +#include "nsIProgressEventSink.h" +#include "nsIChannelEventSink.h" +#include "nsIAsyncVerifyRedirectCallback.h" +#include "nsIInterfaceRequestor.h" +#include "nsIObserverService.h" +#include "nsIObserver.h" +#include "nsIStreamListener.h" +#include "nsIFile.h" +#include "nsIHttpChannel.h" +#include "nsITimer.h" +#include "nsIURI.h" +#include "nsIInputStream.h" +#include "nsNetUtil.h" +#include "nsWeakReference.h" +#include "prio.h" +#include "prprf.h" +#include <algorithm> +#include "nsIContentPolicy.h" +#include "nsContentUtils.h" +#include "mozilla/UniquePtr.h" + +// Default values used to initialize a nsIncrementalDownload object. +#define DEFAULT_CHUNK_SIZE (4096 * 16) // bytes +#define DEFAULT_INTERVAL 60 // seconds + +#define UPDATE_PROGRESS_INTERVAL PRTime(100 * PR_USEC_PER_MSEC) // 100ms + +// Number of times to retry a failed byte-range request. +#define MAX_RETRY_COUNT 20 + +using namespace mozilla; +using namespace mozilla::net; + +//----------------------------------------------------------------------------- + +static nsresult WriteToFile(nsIFile* lf, const char* data, uint32_t len, + int32_t flags) { + PRFileDesc* fd; + int32_t mode = 0600; + nsresult rv; + rv = lf->OpenNSPRFileDesc(flags, mode, &fd); + if (NS_FAILED(rv)) return rv; + + if (len) { + rv = PR_Write(fd, data, len) == int32_t(len) ? NS_OK : NS_ERROR_FAILURE; + } + + PR_Close(fd); + return rv; +} + +static nsresult AppendToFile(nsIFile* lf, const char* data, uint32_t len) { + int32_t flags = PR_WRONLY | PR_CREATE_FILE | PR_APPEND; + return WriteToFile(lf, data, len, flags); +} + +// maxSize may be -1 if unknown +static void MakeRangeSpec(const int64_t& size, const int64_t& maxSize, + int32_t chunkSize, bool fetchRemaining, + nsCString& rangeSpec) { + rangeSpec.AssignLiteral("bytes="); + rangeSpec.AppendInt(int64_t(size)); + rangeSpec.Append('-'); + + if (fetchRemaining) return; + + int64_t end = size + int64_t(chunkSize); + if (maxSize != int64_t(-1) && end > maxSize) end = maxSize; + end -= 1; + + rangeSpec.AppendInt(int64_t(end)); +} + +//----------------------------------------------------------------------------- + +class nsIncrementalDownload final : public nsIIncrementalDownload, + public nsIStreamListener, + public nsIObserver, + public nsIInterfaceRequestor, + public nsIChannelEventSink, + public nsSupportsWeakReference, + public nsIAsyncVerifyRedirectCallback { + public: + NS_DECL_ISUPPORTS + NS_DECL_NSIREQUEST + NS_DECL_NSIINCREMENTALDOWNLOAD + NS_DECL_NSIREQUESTOBSERVER + NS_DECL_NSISTREAMLISTENER + NS_DECL_NSIOBSERVER + NS_DECL_NSIINTERFACEREQUESTOR + NS_DECL_NSICHANNELEVENTSINK + NS_DECL_NSIASYNCVERIFYREDIRECTCALLBACK + + nsIncrementalDownload() = default; + + private: + ~nsIncrementalDownload() = default; + nsresult FlushChunk(); + void UpdateProgress(); + nsresult CallOnStartRequest(); + void CallOnStopRequest(); + nsresult StartTimer(int32_t interval); + nsresult ProcessTimeout(); + nsresult ReadCurrentSize(); + nsresult ClearRequestHeader(nsIHttpChannel* channel); + + nsCOMPtr<nsIRequestObserver> mObserver; + nsCOMPtr<nsIProgressEventSink> mProgressSink; + nsCOMPtr<nsIURI> mURI; + nsCOMPtr<nsIURI> mFinalURI; + nsCOMPtr<nsIFile> mDest; + nsCOMPtr<nsIChannel> mChannel; + nsCOMPtr<nsITimer> mTimer; + mozilla::UniquePtr<char[]> mChunk; + int32_t mChunkLen{0}; + int32_t mChunkSize{DEFAULT_CHUNK_SIZE}; + int32_t mInterval{DEFAULT_INTERVAL}; + int64_t mTotalSize{-1}; + int64_t mCurrentSize{-1}; + uint32_t mLoadFlags{LOAD_NORMAL}; + int32_t mNonPartialCount{0}; + nsresult mStatus{NS_OK}; + bool mIsPending{false}; + bool mDidOnStartRequest{false}; + PRTime mLastProgressUpdate{0}; + nsCOMPtr<nsIAsyncVerifyRedirectCallback> mRedirectCallback; + nsCOMPtr<nsIChannel> mNewRedirectChannel; + nsCString mPartialValidator; + bool mCacheBust{false}; + + // nsITimerCallback is implemented on a subclass so that the name attribute + // doesn't conflict with the name attribute of the nsIRequest interface. + class TimerCallback final : public nsITimerCallback, public nsINamed { + public: + NS_DECL_ISUPPORTS + NS_DECL_NSITIMERCALLBACK + NS_DECL_NSINAMED + + explicit TimerCallback(nsIncrementalDownload* aIncrementalDownload); + + private: + ~TimerCallback() = default; + + RefPtr<nsIncrementalDownload> mIncrementalDownload; + }; +}; + +nsresult nsIncrementalDownload::FlushChunk() { + NS_ASSERTION(mTotalSize != int64_t(-1), "total size should be known"); + + if (mChunkLen == 0) return NS_OK; + + nsresult rv = AppendToFile(mDest, mChunk.get(), mChunkLen); + if (NS_FAILED(rv)) return rv; + + mCurrentSize += int64_t(mChunkLen); + mChunkLen = 0; + + return NS_OK; +} + +void nsIncrementalDownload::UpdateProgress() { + mLastProgressUpdate = PR_Now(); + + if (mProgressSink) { + mProgressSink->OnProgress(this, mCurrentSize + mChunkLen, mTotalSize); + } +} + +nsresult nsIncrementalDownload::CallOnStartRequest() { + if (!mObserver || mDidOnStartRequest) return NS_OK; + + mDidOnStartRequest = true; + return mObserver->OnStartRequest(this); +} + +void nsIncrementalDownload::CallOnStopRequest() { + if (!mObserver) return; + + // Ensure that OnStartRequest is always called once before OnStopRequest. + nsresult rv = CallOnStartRequest(); + if (NS_SUCCEEDED(mStatus)) mStatus = rv; + + mIsPending = false; + + mObserver->OnStopRequest(this, mStatus); + mObserver = nullptr; +} + +nsresult nsIncrementalDownload::StartTimer(int32_t interval) { + auto callback = MakeRefPtr<TimerCallback>(this); + return NS_NewTimerWithCallback(getter_AddRefs(mTimer), callback, + interval * 1000, nsITimer::TYPE_ONE_SHOT); +} + +nsresult nsIncrementalDownload::ProcessTimeout() { + NS_ASSERTION(!mChannel, "how can we have a channel?"); + + // Handle existing error conditions + if (NS_FAILED(mStatus)) { + CallOnStopRequest(); + return NS_OK; + } + + // Fetch next chunk + + nsCOMPtr<nsIChannel> channel; + nsresult rv = NS_NewChannel( + getter_AddRefs(channel), mFinalURI, nsContentUtils::GetSystemPrincipal(), + nsILoadInfo::SEC_ALLOW_CROSS_ORIGIN_SEC_CONTEXT_IS_NULL, + nsIContentPolicy::TYPE_OTHER, + nullptr, // nsICookieJarSettings + nullptr, // PerformanceStorage + nullptr, // loadGroup + this, // aCallbacks + mLoadFlags); + + if (NS_FAILED(rv)) return rv; + + nsCOMPtr<nsIHttpChannel> http = do_QueryInterface(channel, &rv); + if (NS_FAILED(rv)) return rv; + + NS_ASSERTION(mCurrentSize != int64_t(-1), + "we should know the current file size by now"); + + rv = ClearRequestHeader(http); + if (NS_FAILED(rv)) return rv; + + // Don't bother making a range request if we are just going to fetch the + // entire document. + if (mInterval || mCurrentSize != int64_t(0)) { + nsAutoCString range; + MakeRangeSpec(mCurrentSize, mTotalSize, mChunkSize, mInterval == 0, range); + + rv = http->SetRequestHeader("Range"_ns, range, false); + if (NS_FAILED(rv)) return rv; + + if (!mPartialValidator.IsEmpty()) { + rv = http->SetRequestHeader("If-Range"_ns, mPartialValidator, false); + if (NS_FAILED(rv)) { + LOG( + ("nsIncrementalDownload::ProcessTimeout\n" + " failed to set request header: If-Range\n")); + } + } + + if (mCacheBust) { + rv = http->SetRequestHeader("Cache-Control"_ns, "no-cache"_ns, false); + if (NS_FAILED(rv)) { + LOG( + ("nsIncrementalDownload::ProcessTimeout\n" + " failed to set request header: If-Range\n")); + } + rv = http->SetRequestHeader("Pragma"_ns, "no-cache"_ns, false); + if (NS_FAILED(rv)) { + LOG( + ("nsIncrementalDownload::ProcessTimeout\n" + " failed to set request header: If-Range\n")); + } + } + } + + rv = channel->AsyncOpen(this); + if (NS_FAILED(rv)) return rv; + + // Wait to assign mChannel when we know we are going to succeed. This is + // important because we don't want to introduce a reference cycle between + // mChannel and this until we know for a fact that AsyncOpen has succeeded, + // thus ensuring that our stream listener methods will be invoked. + mChannel = channel; + return NS_OK; +} + +// Reads the current file size and validates it. +nsresult nsIncrementalDownload::ReadCurrentSize() { + int64_t size; + nsresult rv = mDest->GetFileSize((int64_t*)&size); + if (rv == NS_ERROR_FILE_NOT_FOUND) { + mCurrentSize = 0; + return NS_OK; + } + if (NS_FAILED(rv)) return rv; + + mCurrentSize = size; + return NS_OK; +} + +// nsISupports + +NS_IMPL_ISUPPORTS(nsIncrementalDownload, nsIIncrementalDownload, nsIRequest, + nsIStreamListener, nsIRequestObserver, nsIObserver, + nsIInterfaceRequestor, nsIChannelEventSink, + nsISupportsWeakReference, nsIAsyncVerifyRedirectCallback) + +// nsIRequest + +NS_IMETHODIMP +nsIncrementalDownload::GetName(nsACString& name) { + NS_ENSURE_TRUE(mURI, NS_ERROR_NOT_INITIALIZED); + + return mURI->GetSpec(name); +} + +NS_IMETHODIMP +nsIncrementalDownload::IsPending(bool* isPending) { + *isPending = mIsPending; + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::GetStatus(nsresult* status) { + *status = mStatus; + return NS_OK; +} + +NS_IMETHODIMP nsIncrementalDownload::SetCanceledReason( + const nsACString& aReason) { + return SetCanceledReasonImpl(aReason); +} + +NS_IMETHODIMP nsIncrementalDownload::GetCanceledReason(nsACString& aReason) { + return GetCanceledReasonImpl(aReason); +} + +NS_IMETHODIMP nsIncrementalDownload::CancelWithReason( + nsresult aStatus, const nsACString& aReason) { + return CancelWithReasonImpl(aStatus, aReason); +} + +NS_IMETHODIMP +nsIncrementalDownload::Cancel(nsresult status) { + NS_ENSURE_ARG(NS_FAILED(status)); + + // Ignore this cancelation if we're already canceled. + if (NS_FAILED(mStatus)) return NS_OK; + + mStatus = status; + + // Nothing more to do if callbacks aren't pending. + if (!mIsPending) return NS_OK; + + if (mChannel) { + mChannel->Cancel(mStatus); + NS_ASSERTION(!mTimer, "what is this timer object doing here?"); + } else { + // dispatch a timer callback event to drive invoking our listener's + // OnStopRequest. + if (mTimer) mTimer->Cancel(); + StartTimer(0); + } + + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::Suspend() { return NS_ERROR_NOT_IMPLEMENTED; } + +NS_IMETHODIMP +nsIncrementalDownload::Resume() { return NS_ERROR_NOT_IMPLEMENTED; } + +NS_IMETHODIMP +nsIncrementalDownload::GetLoadFlags(nsLoadFlags* loadFlags) { + *loadFlags = mLoadFlags; + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::SetLoadFlags(nsLoadFlags loadFlags) { + mLoadFlags = loadFlags; + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::GetTRRMode(nsIRequest::TRRMode* aTRRMode) { + return GetTRRModeImpl(aTRRMode); +} + +NS_IMETHODIMP +nsIncrementalDownload::SetTRRMode(nsIRequest::TRRMode aTRRMode) { + return SetTRRModeImpl(aTRRMode); +} + +NS_IMETHODIMP +nsIncrementalDownload::GetLoadGroup(nsILoadGroup** loadGroup) { + return NS_ERROR_NOT_IMPLEMENTED; +} + +NS_IMETHODIMP +nsIncrementalDownload::SetLoadGroup(nsILoadGroup* loadGroup) { + return NS_ERROR_NOT_IMPLEMENTED; +} + +// nsIIncrementalDownload + +NS_IMETHODIMP +nsIncrementalDownload::Init(nsIURI* uri, nsIFile* dest, int32_t chunkSize, + int32_t interval) { + // Keep it simple: only allow initialization once + NS_ENSURE_FALSE(mURI, NS_ERROR_ALREADY_INITIALIZED); + + mDest = dest; + NS_ENSURE_ARG(mDest); + + mURI = uri; + mFinalURI = uri; + + if (chunkSize > 0) mChunkSize = chunkSize; + if (interval >= 0) mInterval = interval; + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::GetURI(nsIURI** result) { + nsCOMPtr<nsIURI> uri = mURI; + uri.forget(result); + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::GetFinalURI(nsIURI** result) { + nsCOMPtr<nsIURI> uri = mFinalURI; + uri.forget(result); + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::GetDestination(nsIFile** result) { + if (!mDest) { + *result = nullptr; + return NS_OK; + } + // Return a clone of mDest so that callers may modify the resulting nsIFile + // without corrupting our internal object. This also works around the fact + // that some nsIFile impls may cache the result of stat'ing the filesystem. + return mDest->Clone(result); +} + +NS_IMETHODIMP +nsIncrementalDownload::GetTotalSize(int64_t* result) { + *result = mTotalSize; + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::GetCurrentSize(int64_t* result) { + *result = mCurrentSize; + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::Start(nsIRequestObserver* observer, + nsISupports* context) { + NS_ENSURE_ARG(observer); + NS_ENSURE_FALSE(mIsPending, NS_ERROR_IN_PROGRESS); + + // Observe system shutdown so we can be sure to release any reference held + // between ourselves and the timer. We have the observer service hold a weak + // reference to us, so that we don't have to worry about calling + // RemoveObserver. XXX(darin): The timer code should do this for us. + nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService(); + if (obs) obs->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, true); + + nsresult rv = ReadCurrentSize(); + if (NS_FAILED(rv)) return rv; + + rv = StartTimer(0); + if (NS_FAILED(rv)) return rv; + + mObserver = observer; + mProgressSink = do_QueryInterface(observer); // ok if null + + mIsPending = true; + return NS_OK; +} + +// nsIRequestObserver + +NS_IMETHODIMP +nsIncrementalDownload::OnStartRequest(nsIRequest* request) { + nsresult rv; + + nsCOMPtr<nsIHttpChannel> http = do_QueryInterface(request, &rv); + if (NS_FAILED(rv)) return rv; + + // Ensure that we are receiving a 206 response. + uint32_t code; + rv = http->GetResponseStatus(&code); + if (NS_FAILED(rv)) return rv; + if (code != 206) { + // We may already have the entire file downloaded, in which case + // our request for a range beyond the end of the file would have + // been met with an error response code. + if (code == 416 && mTotalSize == int64_t(-1)) { + mTotalSize = mCurrentSize; + // Return an error code here to suppress OnDataAvailable. + return NS_ERROR_DOWNLOAD_COMPLETE; + } + // The server may have decided to give us all of the data in one chunk. If + // we requested a partial range, then we don't want to download all of the + // data at once. So, we'll just try again, but if this keeps happening then + // we'll eventually give up. + if (code == 200) { + if (mInterval) { + mChannel = nullptr; + if (++mNonPartialCount > MAX_RETRY_COUNT) { + NS_WARNING("unable to fetch a byte range; giving up"); + return NS_ERROR_FAILURE; + } + // Increase delay with each failure. + StartTimer(mInterval * mNonPartialCount); + return NS_ERROR_DOWNLOAD_NOT_PARTIAL; + } + // Since we have been asked to download the rest of the file, we can deal + // with a 200 response. This may result in downloading the beginning of + // the file again, but that can't really be helped. + } else { + NS_WARNING("server response was unexpected"); + return NS_ERROR_UNEXPECTED; + } + } else { + // We got a partial response, so clear this counter in case the next chunk + // results in a 200 response. + mNonPartialCount = 0; + + // confirm that the content-range response header is consistent with + // expectations on each 206. If it is not then drop this response and + // retry with no-cache set. + if (!mCacheBust) { + nsAutoCString buf; + int64_t startByte = 0; + bool confirmedOK = false; + + rv = http->GetResponseHeader("Content-Range"_ns, buf); + if (NS_FAILED(rv)) { + return rv; // it isn't a useful 206 without a CONTENT-RANGE of some + } + // sort + + // Content-Range: bytes 0-299999/25604694 + int32_t p = buf.Find("bytes "); + + // first look for the starting point of the content-range + // to make sure it is what we expect + if (p != -1) { + char* endptr = nullptr; + const char* s = buf.get() + p + 6; + while (*s && *s == ' ') s++; + startByte = strtol(s, &endptr, 10); + + if (*s && endptr && (endptr != s) && (mCurrentSize == startByte)) { + // ok the starting point is confirmed. We still need to check the + // total size of the range for consistency if this isn't + // the first chunk + if (mTotalSize == int64_t(-1)) { + // first chunk + confirmedOK = true; + } else { + int32_t slash = buf.FindChar('/'); + int64_t rangeSize = 0; + if (slash != kNotFound && + (PR_sscanf(buf.get() + slash + 1, "%lld", + (int64_t*)&rangeSize) == 1) && + rangeSize == mTotalSize) { + confirmedOK = true; + } + } + } + } + + if (!confirmedOK) { + NS_WARNING("unexpected content-range"); + mCacheBust = true; + mChannel = nullptr; + if (++mNonPartialCount > MAX_RETRY_COUNT) { + NS_WARNING("unable to fetch a byte range; giving up"); + return NS_ERROR_FAILURE; + } + // Increase delay with each failure. + StartTimer(mInterval * mNonPartialCount); + return NS_ERROR_DOWNLOAD_NOT_PARTIAL; + } + } + } + + // Do special processing after the first response. + if (mTotalSize == int64_t(-1)) { + // Update knowledge of mFinalURI + rv = http->GetURI(getter_AddRefs(mFinalURI)); + if (NS_FAILED(rv)) return rv; + Unused << http->GetResponseHeader("Etag"_ns, mPartialValidator); + if (StringBeginsWith(mPartialValidator, "W/"_ns)) { + mPartialValidator.Truncate(); // don't use weak validators + } + if (mPartialValidator.IsEmpty()) { + rv = http->GetResponseHeader("Last-Modified"_ns, mPartialValidator); + if (NS_FAILED(rv)) { + LOG( + ("nsIncrementalDownload::OnStartRequest\n" + " empty validator\n")); + } + } + + if (code == 206) { + // OK, read the Content-Range header to determine the total size of this + // download file. + nsAutoCString buf; + rv = http->GetResponseHeader("Content-Range"_ns, buf); + if (NS_FAILED(rv)) return rv; + int32_t slash = buf.FindChar('/'); + if (slash == kNotFound) { + NS_WARNING("server returned invalid Content-Range header!"); + return NS_ERROR_UNEXPECTED; + } + if (PR_sscanf(buf.get() + slash + 1, "%lld", (int64_t*)&mTotalSize) != + 1) { + return NS_ERROR_UNEXPECTED; + } + } else { + rv = http->GetContentLength(&mTotalSize); + if (NS_FAILED(rv)) return rv; + // We need to know the total size of the thing we're trying to download. + if (mTotalSize == int64_t(-1)) { + NS_WARNING("server returned no content-length header!"); + return NS_ERROR_UNEXPECTED; + } + // Need to truncate (or create, if it doesn't exist) the file since we + // are downloading the whole thing. + WriteToFile(mDest, nullptr, 0, PR_WRONLY | PR_CREATE_FILE | PR_TRUNCATE); + mCurrentSize = 0; + } + + // Notify observer that we are starting... + rv = CallOnStartRequest(); + if (NS_FAILED(rv)) return rv; + } + + // Adjust mChunkSize accordingly if mCurrentSize is close to mTotalSize. + int64_t diff = mTotalSize - mCurrentSize; + if (diff <= int64_t(0)) { + NS_WARNING("about to set a bogus chunk size; giving up"); + return NS_ERROR_UNEXPECTED; + } + + if (diff < int64_t(mChunkSize)) mChunkSize = uint32_t(diff); + + mChunk = mozilla::MakeUniqueFallible<char[]>(mChunkSize); + if (!mChunk) rv = NS_ERROR_OUT_OF_MEMORY; + + return rv; +} + +NS_IMETHODIMP +nsIncrementalDownload::OnStopRequest(nsIRequest* request, nsresult status) { + // Not a real error; just a trick to kill off the channel without our + // listener having to care. + if (status == NS_ERROR_DOWNLOAD_NOT_PARTIAL) return NS_OK; + + // Not a real error; just a trick used to suppress OnDataAvailable calls. + if (status == NS_ERROR_DOWNLOAD_COMPLETE) status = NS_OK; + + if (NS_SUCCEEDED(mStatus)) mStatus = status; + + if (mChunk) { + if (NS_SUCCEEDED(mStatus)) mStatus = FlushChunk(); + + mChunk = nullptr; // deletes memory + mChunkLen = 0; + UpdateProgress(); + } + + mChannel = nullptr; + + // Notify listener if we hit an error or finished + if (NS_FAILED(mStatus) || mCurrentSize == mTotalSize) { + CallOnStopRequest(); + return NS_OK; + } + + return StartTimer(mInterval); // Do next chunk +} + +// nsIStreamListener + +NS_IMETHODIMP +nsIncrementalDownload::OnDataAvailable(nsIRequest* request, + nsIInputStream* input, uint64_t offset, + uint32_t count) { + while (count) { + uint32_t space = mChunkSize - mChunkLen; + uint32_t n, len = std::min(space, count); + + nsresult rv = input->Read(&mChunk[mChunkLen], len, &n); + if (NS_FAILED(rv)) return rv; + if (n != len) return NS_ERROR_UNEXPECTED; + + count -= n; + mChunkLen += n; + + if (mChunkLen == mChunkSize) { + rv = FlushChunk(); + if (NS_FAILED(rv)) return rv; + } + } + + if (PR_Now() > mLastProgressUpdate + UPDATE_PROGRESS_INTERVAL) { + UpdateProgress(); + } + + return NS_OK; +} + +// nsIObserver + +NS_IMETHODIMP +nsIncrementalDownload::Observe(nsISupports* subject, const char* topic, + const char16_t* data) { + if (strcmp(topic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) { + Cancel(NS_ERROR_ABORT); + + // Since the app is shutting down, we need to go ahead and notify our + // observer here. Otherwise, we would notify them after XPCOM has been + // shutdown or not at all. + CallOnStopRequest(); + } + return NS_OK; +} + +// nsITimerCallback + +nsIncrementalDownload::TimerCallback::TimerCallback( + nsIncrementalDownload* aIncrementalDownload) + : mIncrementalDownload(aIncrementalDownload) {} + +NS_IMPL_ISUPPORTS(nsIncrementalDownload::TimerCallback, nsITimerCallback, + nsINamed) + +NS_IMETHODIMP +nsIncrementalDownload::TimerCallback::Notify(nsITimer* aTimer) { + mIncrementalDownload->mTimer = nullptr; + + nsresult rv = mIncrementalDownload->ProcessTimeout(); + if (NS_FAILED(rv)) mIncrementalDownload->Cancel(rv); + + return NS_OK; +} + +// nsINamed + +NS_IMETHODIMP +nsIncrementalDownload::TimerCallback::GetName(nsACString& aName) { + aName.AssignLiteral("nsIncrementalDownload"); + return NS_OK; +} + +// nsIInterfaceRequestor + +NS_IMETHODIMP +nsIncrementalDownload::GetInterface(const nsIID& iid, void** result) { + if (iid.Equals(NS_GET_IID(nsIChannelEventSink))) { + NS_ADDREF_THIS(); + *result = static_cast<nsIChannelEventSink*>(this); + return NS_OK; + } + + nsCOMPtr<nsIInterfaceRequestor> ir = do_QueryInterface(mObserver); + if (ir) return ir->GetInterface(iid, result); + + return NS_ERROR_NO_INTERFACE; +} + +nsresult nsIncrementalDownload::ClearRequestHeader(nsIHttpChannel* channel) { + NS_ENSURE_ARG(channel); + + // We don't support encodings -- they make the Content-Length not equal + // to the actual size of the data. + return channel->SetRequestHeader("Accept-Encoding"_ns, ""_ns, false); +} + +// nsIChannelEventSink + +NS_IMETHODIMP +nsIncrementalDownload::AsyncOnChannelRedirect( + nsIChannel* oldChannel, nsIChannel* newChannel, uint32_t flags, + nsIAsyncVerifyRedirectCallback* cb) { + // In response to a redirect, we need to propagate the Range header. See bug + // 311595. Any failure code returned from this function aborts the redirect. + + nsCOMPtr<nsIHttpChannel> http = do_QueryInterface(oldChannel); + NS_ENSURE_STATE(http); + + nsCOMPtr<nsIHttpChannel> newHttpChannel = do_QueryInterface(newChannel); + NS_ENSURE_STATE(newHttpChannel); + + constexpr auto rangeHdr = "Range"_ns; + + nsresult rv = ClearRequestHeader(newHttpChannel); + if (NS_FAILED(rv)) return rv; + + // If we didn't have a Range header, then we must be doing a full download. + nsAutoCString rangeVal; + Unused << http->GetRequestHeader(rangeHdr, rangeVal); + if (!rangeVal.IsEmpty()) { + rv = newHttpChannel->SetRequestHeader(rangeHdr, rangeVal, false); + NS_ENSURE_SUCCESS(rv, rv); + } + + // A redirection changes the validator + mPartialValidator.Truncate(); + + if (mCacheBust) { + rv = newHttpChannel->SetRequestHeader("Cache-Control"_ns, "no-cache"_ns, + false); + if (NS_FAILED(rv)) { + LOG( + ("nsIncrementalDownload::AsyncOnChannelRedirect\n" + " failed to set request header: Cache-Control\n")); + } + rv = newHttpChannel->SetRequestHeader("Pragma"_ns, "no-cache"_ns, false); + if (NS_FAILED(rv)) { + LOG( + ("nsIncrementalDownload::AsyncOnChannelRedirect\n" + " failed to set request header: Pragma\n")); + } + } + + // Prepare to receive callback + mRedirectCallback = cb; + mNewRedirectChannel = newChannel; + + // Give the observer a chance to see this redirect notification. + nsCOMPtr<nsIChannelEventSink> sink = do_GetInterface(mObserver); + if (sink) { + rv = sink->AsyncOnChannelRedirect(oldChannel, newChannel, flags, this); + if (NS_FAILED(rv)) { + mRedirectCallback = nullptr; + mNewRedirectChannel = nullptr; + } + return rv; + } + (void)OnRedirectVerifyCallback(NS_OK); + return NS_OK; +} + +NS_IMETHODIMP +nsIncrementalDownload::OnRedirectVerifyCallback(nsresult result) { + NS_ASSERTION(mRedirectCallback, "mRedirectCallback not set in callback"); + NS_ASSERTION(mNewRedirectChannel, "mNewRedirectChannel not set in callback"); + + // Update mChannel, so we can Cancel the new channel. + if (NS_SUCCEEDED(result)) mChannel = mNewRedirectChannel; + + mRedirectCallback->OnRedirectVerifyCallback(result); + mRedirectCallback = nullptr; + mNewRedirectChannel = nullptr; + return NS_OK; +} + +extern nsresult net_NewIncrementalDownload(const nsIID& iid, void** result) { + RefPtr<nsIncrementalDownload> d = new nsIncrementalDownload(); + return d->QueryInterface(iid, result); +} |