The old implementation calculates download/upload statistics for a
RequestGroup by summing up all PeerStat objects. For global
statistics, those are summed together. This clearly incurs runtime
penalty and we introduced some kind of caching which updates
statistics every 250ms but it did not work right.
This change removes all these aggregation code, and instead makes
RequestGroup and RequestGroupMan objects hold NetStat object and
download/upload bytes are directly calculated by thier own NetStat.
This is far more simplar than the old way and less runtime penalty and
brings more accuracy.
If true is given, which is default, save the uploaded torrent or
metalink metadata in the directory specified by --dir option. The
filename consists of SHA1-hash hex string of metadata plus
extension. For torrent, the extension is '.torrent'. For metalink, it
is '.meta4'. If false is given to this option, the downloads added by
aria2.addTorrent or aria2.addMetalink will not be saved by
--save-session option.
In this change, we defined HTTP header fields we are interested in.
We only store those headers in HttpHeader object. Accessing HTTP
headers in HttpHeader object is now done through enum values.
DownloadHandlerConstants was simplified. MIME type handling in Accept
header was also reworked. DownloadContext's metalinkServerContacted_
is replaced with acceptMetalink_ and its boolean value is reverted.
RequestGroup and HttpRequest now do not hold vector of accepting
types. HttpRequest has the flag acceptMetalink_ which will be set by
the same value of DownloadContext::accpetMetalink_ and if it is true,
Metalink MIME types are added to Accept header field.
Using off_t, at least, in DiskAdaptor layer is problematic because
torrent can contain under 2GiB files but total sum of those files may
exceed 2GiB limit, which makes off_t overflow in 32 bit system without
large file support. So we use int64_t in API. We'll check the file
length before download so that it does not exceed max off_t.
We only percent-decode filename* value in Content-Disposition because
the encoding is fully specified. But since filename value is not, so
we just accept it as is.
The old implementation calls at least 2 read(2) (4bytes length and
payload) to receive the message. This change will read as many bytes
as possible in one read(2) call. BtPieceMessage::data_ is now just a
const pointer to the internal buffer of PeerConnection.