int CWebServer::CreateRangedMemoryDownloadResponse(const std::shared_ptr<IHTTPRequestHandler>& handler, struct MHD_Response *&response) const
{
if (handler == nullptr)
return MHD_NO;
const HTTPRequest &request = handler->GetRequest();
const HTTPResponseDetails &responseDetails = handler->GetResponseDetails();
HttpResponseRanges responseRanges = handler->GetResponseData();
// if there's no or only one range this is not the right place
if (responseRanges.size() <= 1)
return CreateMemoryDownloadResponse(handler, response);
// extract all the valid ranges and calculate their total length
uint64_t firstRangePosition = 0;
HttpResponseRanges ranges;
for (HttpResponseRanges::const_iterator range = responseRanges.begin(); range != responseRanges.end(); ++range)
{
// ignore invalid ranges
if (!range->IsValid())
continue;
// determine the first range position
if (ranges.empty())
firstRangePosition = range->GetFirstPosition();
ranges.push_back(*range);
}
if (ranges.empty())
return CreateMemoryDownloadResponse(request.connection, nullptr, 0, false, false, response);
// determine the last range position
uint64_t lastRangePosition = ranges.back().GetLastPosition();
// adjust the HTTP status of the response
handler->SetResponseStatus(MHD_HTTP_PARTIAL_CONTENT);
// add Content-Range header
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_RANGE,
HttpRangeUtils::GenerateContentRangeHeaderValue(firstRangePosition, lastRangePosition, responseDetails.totalLength));
// generate a multipart boundary
std::string multipartBoundary = HttpRangeUtils::GenerateMultipartBoundary();
// and the content-type
std::string contentType = HttpRangeUtils::GenerateMultipartBoundaryContentType(multipartBoundary);
// add Content-Type header
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_TYPE, contentType);
// generate the multipart boundary with the Content-Type header field
std::string multipartBoundaryWithHeader = HttpRangeUtils::GenerateMultipartBoundaryWithHeader(multipartBoundary, contentType);
std::string result;
// add all the ranges to the result
for (HttpResponseRanges::const_iterator range = ranges.begin(); range != ranges.end(); ++range)
{
// add a newline before any new multipart boundary
if (range != ranges.begin())
result += HEADER_NEWLINE;
// generate and append the multipart boundary with the full header (Content-Type and Content-Length)
result += HttpRangeUtils::GenerateMultipartBoundaryWithHeader(multipartBoundaryWithHeader, &*range);
// and append the data of the range
result.append(static_cast<const char*>(range->GetData()), static_cast<size_t>(range->GetLength()));
// check if we need to free the range data
if (responseDetails.type == HTTPMemoryDownloadFreeNoCopy || responseDetails.type == HTTPMemoryDownloadFreeCopy)
free(const_cast<void*>(range->GetData()));
}
result += HttpRangeUtils::GenerateMultipartBoundaryEnd(multipartBoundary);
// add Content-Length header
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_LENGTH, StringUtils::Format("%" PRIu64, static_cast<uint64_t>(result.size())));
// finally create the response
return CreateMemoryDownloadResponse(request.connection, result.c_str(), result.size(), false, true, response);
}
int CWebServer::CreateFileDownloadResponse(const std::shared_ptr<IHTTPRequestHandler>& handler, struct MHD_Response *&response) const
{
if (handler == nullptr)
return MHD_NO;
const HTTPRequest &request = handler->GetRequest();
const HTTPResponseDetails &responseDetails = handler->GetResponseDetails();
HttpResponseRanges responseRanges = handler->GetResponseData();
std::shared_ptr<XFILE::CFile> file = std::make_shared<XFILE::CFile>();
std::string filePath = handler->GetResponseFile();
if (!file->Open(filePath, XFILE::READ_NO_CACHE))
{
CLog::Log(LOGERROR, "CWebServer[%hu]: Failed to open %s", m_port, filePath.c_str());
return SendErrorResponse(request, MHD_HTTP_NOT_FOUND, request.method);
}
bool ranged = false;
uint64_t fileLength = static_cast<uint64_t>(file->GetLength());
// get the MIME type for the Content-Type header
std::string mimeType = responseDetails.contentType;
if (mimeType.empty())
{
std::string ext = URIUtils::GetExtension(filePath);
StringUtils::ToLower(ext);
mimeType = CreateMimeTypeFromExtension(ext.c_str());
}
if (request.method != HEAD)
{
uint64_t totalLength = 0;
std::unique_ptr<HttpFileDownloadContext> context(new HttpFileDownloadContext());
context->file = file;
context->contentType = mimeType;
context->boundaryWritten = false;
context->writePosition = 0;
if (handler->IsRequestRanged())
{
if (!request.ranges.IsEmpty())
context->ranges = request.ranges;
else
HTTPRequestHandlerUtils::GetRequestedRanges(request.connection, fileLength, context->ranges);
}
uint64_t firstPosition = 0;
uint64_t lastPosition = 0;
// if there are no ranges, add the whole range
if (context->ranges.IsEmpty())
context->ranges.Add(CHttpRange(0, fileLength - 1));
else
{
handler->SetResponseStatus(MHD_HTTP_PARTIAL_CONTENT);
// we need to remember that we are ranged because the range length might change and won't be reliable anymore for length comparisons
ranged = true;
context->ranges.GetFirstPosition(firstPosition);
context->ranges.GetLastPosition(lastPosition);
}
// remember the total number of ranges
context->rangeCountTotal = context->ranges.Size();
// remember the total length
totalLength = context->ranges.GetLength();
// adjust the MIME type and range length in case of multiple ranges which requires multipart boundaries
if (context->rangeCountTotal > 1)
{
context->boundary = HttpRangeUtils::GenerateMultipartBoundary();
mimeType = HttpRangeUtils::GenerateMultipartBoundaryContentType(context->boundary);
// build part of the boundary with the optional Content-Type header
// "--<boundary>\r\nContent-Type: <content-type>\r\n
context->boundaryWithHeader = HttpRangeUtils::GenerateMultipartBoundaryWithHeader(context->boundary, context->contentType);
context->boundaryEnd = HttpRangeUtils::GenerateMultipartBoundaryEnd(context->boundary);
// for every range, we need to add a boundary with header
for (HttpRanges::const_iterator range = context->ranges.Begin(); range != context->ranges.End(); ++range)
{
// we need to temporarily add the Content-Range header to the boundary to be able to determine the length
std::string completeBoundaryWithHeader = HttpRangeUtils::GenerateMultipartBoundaryWithHeader(context->boundaryWithHeader, &*range);
totalLength += completeBoundaryWithHeader.size();
// add a newline before any new multipart boundary
if (range != context->ranges.Begin())
totalLength += strlen(HEADER_NEWLINE);
}
// and at the very end a special end-boundary "\r\n--<boundary>--"
totalLength += context->boundaryEnd.size();
}
// set the initial write position
context->ranges.GetFirstPosition(context->writePosition);
// create the response object
response = MHD_create_response_from_callback(totalLength, 2048,
&CWebServer::ContentReaderCallback,
context.get(),
&CWebServer::ContentReaderFreeCallback);
if (response == nullptr)
{
CLog::Log(LOGERROR, "CWebServer[%hu]: failed to create a HTTP response for %s to be filled from %s", m_port, request.pathUrl.c_str(), filePath.c_str());
return MHD_NO;
}
context.release(); // ownership was passed to mhd
// add Content-Range header
if (ranged)
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_RANGE, HttpRangeUtils::GenerateContentRangeHeaderValue(firstPosition, lastPosition, fileLength));
}
else
{
response = create_response(0, nullptr, MHD_NO, MHD_NO);
if (response == nullptr)
{
CLog::Log(LOGERROR, "CWebServer[%hu]: failed to create a HTTP HEAD response for %s", m_port, request.pathUrl.c_str());
return MHD_NO;
}
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_LENGTH, StringUtils::Format("%" PRId64, fileLength));
}
// set the Content-Type header
if (!mimeType.empty())
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_TYPE, mimeType);
return MHD_YES;
}
int CWebServer::FinalizeRequest(const std::shared_ptr<IHTTPRequestHandler>& handler, int responseStatus, struct MHD_Response *response)
{
if (handler == nullptr || response == nullptr)
return MHD_NO;
const HTTPRequest &request = handler->GetRequest();
const HTTPResponseDetails &responseDetails = handler->GetResponseDetails();
// if the request handler has set a content type and it hasn't been set as a header, add it
if (!responseDetails.contentType.empty())
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_TYPE, responseDetails.contentType);
// if the request handler has set a last modified date and it hasn't been set as a header, add it
CDateTime lastModified;
if (handler->GetLastModifiedDate(lastModified) && lastModified.IsValid())
handler->AddResponseHeader(MHD_HTTP_HEADER_LAST_MODIFIED, lastModified.GetAsRFC1123DateTime());
// check if the request handler has set Cache-Control and add it if not
if (!handler->HasResponseHeader(MHD_HTTP_HEADER_CACHE_CONTROL))
{
int maxAge = handler->GetMaximumAgeForCaching();
if (handler->CanBeCached() && maxAge == 0 && !responseDetails.contentType.empty())
{
// don't cache HTML, CSS and JavaScript files
if (!StringUtils::EqualsNoCase(responseDetails.contentType, "text/html") &&
!StringUtils::EqualsNoCase(responseDetails.contentType, "text/css") &&
!StringUtils::EqualsNoCase(responseDetails.contentType, "application/javascript"))
maxAge = CDateTimeSpan(365, 0, 0, 0).GetSecondsTotal();
}
// if the response can't be cached or the maximum age is 0 force the client not to cache
if (!handler->CanBeCached() || maxAge == 0)
handler->AddResponseHeader(MHD_HTTP_HEADER_CACHE_CONTROL, "private, max-age=0, " HEADER_VALUE_NO_CACHE);
else
{
// create the value of the Cache-Control header
std::string cacheControl = StringUtils::Format("public, max-age=%d", maxAge);
// check if the response contains a Set-Cookie header because they must not be cached
if (handler->HasResponseHeader(MHD_HTTP_HEADER_SET_COOKIE))
cacheControl += ", no-cache=\"set-cookie\"";
// set the Cache-Control header
handler->AddResponseHeader(MHD_HTTP_HEADER_CACHE_CONTROL, cacheControl);
// set the Expires header
CDateTime expiryTime = CDateTime::GetCurrentDateTime() + CDateTimeSpan(0, 0, 0, maxAge);
handler->AddResponseHeader(MHD_HTTP_HEADER_EXPIRES, expiryTime.GetAsRFC1123DateTime());
}
}
// if the request handler can handle ranges and it hasn't been set as a header, add it
if (handler->CanHandleRanges())
handler->AddResponseHeader(MHD_HTTP_HEADER_ACCEPT_RANGES, "bytes");
else
handler->AddResponseHeader(MHD_HTTP_HEADER_ACCEPT_RANGES, "none");
// add MHD_HTTP_HEADER_CONTENT_LENGTH
if (responseDetails.totalLength > 0)
handler->AddResponseHeader(MHD_HTTP_HEADER_CONTENT_LENGTH, StringUtils::Format("%" PRIu64, responseDetails.totalLength));
// add all headers set by the request handler
for (std::multimap<std::string, std::string>::const_iterator it = responseDetails.headers.begin(); it != responseDetails.headers.end(); ++it)
AddHeader(response, it->first, it->second);
return SendResponse(request, responseStatus, response);
}
