gecko/netwerk/base/nsIncrementalDownload.cpp

933 lines
26 KiB
C++

/* -*- 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 "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 "nsITimer.h"
#include "nsIURI.h"
#include "nsIInputStream.h"
#include "nsNetUtil.h"
#include "nsAutoPtr.h"
#include "nsWeakReference.h"
#include "prio.h"
#include "prprf.h"
#include <algorithm>
#include "nsIContentPolicy.h"
#include "nsContentUtils.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(500 * PR_USEC_PER_MSEC) // 500ms
// Number of times to retry a failed byte-range request.
#define MAX_RETRY_COUNT 20
//-----------------------------------------------------------------------------
static nsresult
WriteToFile(nsIFile *lf, const char *data, uint32_t len, int32_t flags)
{
PRFileDesc *fd;
int32_t mode = 0600;
nsresult rv;
#if defined(MOZ_WIDGET_GONK)
// The sdcard on a B2G phone looks like:
// d---rwx--- system sdcard_rw 1970-01-01 01:00:00 sdcard
// On the emulator, xpcshell fails when using 0600 mode to open the file,
// and 0660 works.
nsCOMPtr<nsIFile> parent;
rv = lf->GetParent(getter_AddRefs(parent));
if (NS_FAILED(rv)) {
return rv;
}
uint32_t parentPerm;
rv = parent->GetPermissions(&parentPerm);
if (NS_FAILED(rv)) {
return rv;
}
if ((parentPerm & 0700) == 0) {
// Parent directory has no owner-write, so try to use group permissions
// instead of owner permissions.
mode = 0660;
}
#endif
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();
private:
~nsIncrementalDownload() {}
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<nsISupports> mObserverContext;
nsCOMPtr<nsIProgressEventSink> mProgressSink;
nsCOMPtr<nsIURI> mURI;
nsCOMPtr<nsIURI> mFinalURI;
nsCOMPtr<nsIFile> mDest;
nsCOMPtr<nsIChannel> mChannel;
nsCOMPtr<nsITimer> mTimer;
nsAutoArrayPtr<char> mChunk;
int32_t mChunkLen;
int32_t mChunkSize;
int32_t mInterval;
int64_t mTotalSize;
int64_t mCurrentSize;
uint32_t mLoadFlags;
int32_t mNonPartialCount;
nsresult mStatus;
bool mIsPending;
bool mDidOnStartRequest;
PRTime mLastProgressUpdate;
nsCOMPtr<nsIAsyncVerifyRedirectCallback> mRedirectCallback;
nsCOMPtr<nsIChannel> mNewRedirectChannel;
nsCString mPartialValidator;
bool mCacheBust;
};
nsIncrementalDownload::nsIncrementalDownload()
: mChunkLen(0)
, mChunkSize(DEFAULT_CHUNK_SIZE)
, mInterval(DEFAULT_INTERVAL)
, mTotalSize(-1)
, mCurrentSize(-1)
, mLoadFlags(LOAD_NORMAL)
, mNonPartialCount(0)
, mStatus(NS_OK)
, mIsPending(false)
, mDidOnStartRequest(false)
, mLastProgressUpdate(0)
, mRedirectCallback(nullptr)
, mNewRedirectChannel(nullptr)
, mCacheBust(false)
{
}
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, 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, mObserverContext,
mCurrentSize + mChunkLen,
mTotalSize);
}
nsresult
nsIncrementalDownload::CallOnStartRequest()
{
if (!mObserver || mDidOnStartRequest)
return NS_OK;
mDidOnStartRequest = true;
return mObserver->OnStartRequest(this, mObserverContext);
}
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, mObserverContext, mStatus);
mObserver = nullptr;
mObserverContext = nullptr;
}
nsresult
nsIncrementalDownload::StartTimer(int32_t interval)
{
nsresult rv;
mTimer = do_CreateInstance(NS_TIMER_CONTRACTID, &rv);
if (NS_FAILED(rv))
return rv;
return mTimer->Init(this, 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_NORMAL,
nsIContentPolicy::TYPE_OTHER,
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(NS_LITERAL_CSTRING("Range"), range, false);
if (NS_FAILED(rv))
return rv;
if (!mPartialValidator.IsEmpty())
http->SetRequestHeader(NS_LITERAL_CSTRING("If-Range"),
mPartialValidator, false);
if (mCacheBust) {
http->SetRequestHeader(NS_LITERAL_CSTRING("Cache-Control"),
NS_LITERAL_CSTRING("no-cache"), false);
http->SetRequestHeader(NS_LITERAL_CSTRING("Pragma"),
NS_LITERAL_CSTRING("no-cache"), false);
}
}
rv = channel->AsyncOpen(this, nullptr);
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 ||
rv == NS_ERROR_FILE_TARGET_DOES_NOT_EXIST) {
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::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::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 = do_QueryInterface(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)
{
NS_IF_ADDREF(*result = mURI);
return NS_OK;
}
NS_IMETHODIMP
nsIncrementalDownload::GetFinalURI(nsIURI **result)
{
NS_IF_ADDREF(*result = mFinalURI);
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;
mObserverContext = context;
mProgressSink = do_QueryInterface(observer); // ok if null
mIsPending = true;
return NS_OK;
}
// nsIRequestObserver
NS_IMETHODIMP
nsIncrementalDownload::OnStartRequest(nsIRequest *request,
nsISupports *context)
{
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(NS_LITERAL_CSTRING("Content-Range"), 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;
http->GetResponseHeader(NS_LITERAL_CSTRING("Etag"), mPartialValidator);
if (StringBeginsWith(mPartialValidator, NS_LITERAL_CSTRING("W/")))
mPartialValidator.Truncate(); // don't use weak validators
if (mPartialValidator.IsEmpty())
http->GetResponseHeader(NS_LITERAL_CSTRING("Last-Modified"), mPartialValidator);
if (code == 206) {
// OK, read the Content-Range header to determine the total size of this
// download file.
nsAutoCString buf;
rv = http->GetResponseHeader(NS_LITERAL_CSTRING("Content-Range"), 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 = new char[mChunkSize];
if (!mChunk)
rv = NS_ERROR_OUT_OF_MEMORY;
return rv;
}
NS_IMETHODIMP
nsIncrementalDownload::OnStopRequest(nsIRequest *request,
nsISupports *context,
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,
nsISupports *context,
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();
}
else if (strcmp(topic, NS_TIMER_CALLBACK_TOPIC) == 0) {
mTimer = nullptr;
nsresult rv = ProcessTimeout();
if (NS_FAILED(rv))
Cancel(rv);
}
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(NS_LITERAL_CSTRING("Accept-Encoding"),
NS_LITERAL_CSTRING(""), 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);
NS_NAMED_LITERAL_CSTRING(rangeHdr, "Range");
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;
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) {
newHttpChannel->SetRequestHeader(NS_LITERAL_CSTRING("Cache-Control"),
NS_LITERAL_CSTRING("no-cache"), false);
newHttpChannel->SetRequestHeader(NS_LITERAL_CSTRING("Pragma"),
NS_LITERAL_CSTRING("no-cache"), false);
}
// 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(nsISupports *outer, const nsIID &iid, void **result)
{
if (outer)
return NS_ERROR_NO_AGGREGATION;
nsIncrementalDownload *d = new nsIncrementalDownload();
if (!d)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(d);
nsresult rv = d->QueryInterface(iid, result);
NS_RELEASE(d);
return rv;
}