Enhanced CTorrent

[ Overview | News | Changes | CTCS | Download | Resources | Contact ]


Overview

CTorrent is a BitTorrent client implemented in C++ to be lightweight and quick. The original has fallen a little behind in updates and bug fixes though.

The files here contain the good work of those who wrote the original CTorrent base code and a number of patches that provide fixes and enhancements, as well as additional fixes and enhancements that I am contributing. I am not the original author, current maintainer, or any other official representative of CTorrent. The files on this page are not the original or official CTorrent distribution. I encourage you to visit the CTorrent project page on SourceForge for further information.

Enhanced CTorrent now has a SourceForge project page with forums, bug reporting, and downloads.

Platform

Enhanced CTorrent is intended to run on any Unix-like system, including FreeBSD, Linux, Mac OS X, Solaris, Cygwin, etc. If it doesn't build or run properly without modification on your system, please post to the forums or send details.

Features

The purpose of the Enhanced CTorrent effort is to fix problems that remain in the code, modernize existing features and algorithms, and implement new features while maintaining low overhead requirements and a high standard of performance (both part of the original CTorrent design philosophy). Highlights of the enhanced client include:

Documentation

For documentation that provides a little more than the help screen, please see the User's Guide.

For a list of changes in the current and previous versions, see the ChangeLog file.

Peer ID

Beginning with dnh1.1 the default peer ID has been changed for convenience, as some other clients and trackers assume that Ctorrent is "buggy" and won't cooperate with it. [Guess what, there are plenty of others with bugs too.] The -P option is still available if you wish to use a different peer ID, but it is no longer necessary to do so in order to avoid this "ban".

The new default peer ID prefix is "-CDversion-", where version is an indication of the version number (0101 for dnh1.1).

CTCS

CTorrent Control Server (CTCS) is an interface for monitoring and managing Enhanced CTorrent clients. It can manage allocation of bandwidth, provide status information, and allow changes to the running configuration of each client. Support for this interface was added in the dnh2 release.


News

2008-06-14
Version dnh3.3.2 is released. This is a bug-fix release to correct known issues in dnh3.3.1.
2008-04-26
Version dnh3.3.1 is released. This is a bug-fix release to correct known issues in dnh3.3.
CTCS 1.4.1 has also been released.
2008-04-08
Version dnh3.3 is released. This release includes a number of bug fixes and optimizations; details are in the change log.
2007-11-27
There is a bug in dnh3.2 that can cause a completed torrent to be reported as incomplete when restarting. An easy correction is to delete the "setvbuf" line in btfiles.cpp and recompile. This is recommended even if you have not observed the problem.

While I'm here I may as well announce the new SourceForge project page! This should be a big help toward organizing communications, tracking bugs, and maintaining code history.

2007-07-23
Version dnh3.2 is released. This release includes a number of bug fixes and some optimizations; details are in the change log.
2007-06-13
The timestamp on one of the autoconf files was incorrect, which may have caused build problems for some people. The dnh3.1 release package has been updated to correct this.
2007-06-10
A possible crash when exiting the program has been corrected. The bug is essentially harmless except that you might have a core file created as a result. The dnh3.1 release package has been updated below to correct this.
2007-06-05
Version dnh3.1 is released. There are several new features and bug fixes; details can be found in the change log. If you're using CTCS, you should also upgrade it to version 1.4 in order to use new client configuration options.
2007-05-23
The dnh3-update patch has been updated to fix a potential crash, and a rate measurement issue on some devices.
2007-04-27
A couple more critical issues in release dnh3 have been found and fixed. To reduce any confusion or inconvenience in the tracking and application of patches, all such fixes will now be distributed in a single patch file that will be updated as necessary, while its name will not change. See the Download section for more details.
2007-04-18
Two patches are available for dnh3; one corrects a general problem and the other provides support for Mac OSX.
2007-04-11
Version dnh3 is released. There are several significant new features; release notes can be found in the change log. If you're using CTCS, you should also upgrade it to version 1.3 so that bandwidth management will work correctly.
2007-02-25
A patch is available to fix a bug that can cause a crash when reassigning a piece for download.
2006-11-05
Version dnh2.2 is released, mostly for bug fixes. Thanks to those who have reported them and helped with debugging!
A simple user's guide is also available.
2006-09-03
Version dnh2.1 is released, along with CTCS 1.1. Both updates fix issues when using CTCS on Linux, among other things.
2006-04-26
The CTCS protocol is finally documented.
2006-04-25
A patch is available to fix a bug in my solution for the vfat filesystem issue. This bug can cause the client to crash when creating a file on any filesystem type; the patch is recommended for all users.
2006-01-15
Version dnh2 is released! This version includes a number of significant changes, including large file support, piece selection, tuned request queue depth, and support for CTorrent Control Server.


Download

The preferred download mechanism is now the SourceForge File Release page. All new files will be available there for convenient downloading from a mirror site near to you.

Newer files appear first in the list. Note that patches are generally intended for the version below (older than) the patch.


Release dnh3.3.2

SourceForge download page
Alternate (source distribution)



Release dnh3.3.1

SourceForge download page
Alternate (source distribution)


Release dnh3.3

SourceForge download page
Alternate (source distribution)
A complete source distribution for all platforms.


Release dnh3.2

Source distribution
A complete source distribution for all platforms.


Release dnh3.1

Source distribution
A complete source distribution for all platforms.


Release dnh3 Update Patch

dnh3_update patch (23 May 2007)
This patch provides critical updates to release dnh3. The patch file will be updated here as necessary if additional such issues are found.

This patch file contains the following component patches (not all were previously posted individually):

msg
Fixes a potential crash recording or reporting the type of message received from a peer. This could happen on multiple message types but may be likeliest to happen upon download completion (becoming seed).
bwrate
A problem has been observed with bandwidth rate measurement on NSLU2 devices. This appears to be due to a compiler or platform bug of some sort, but the root cause is not yet known. As such, it's possible that it may affect builds for other ARM devices or builds that use the same versions of build tools. While the problem is cosmetic with respect to bandwidth limiting, it can affect client operation in other ways. This patch provides a permanent workaround for this particular issue, but note that similar types of calculations are used in other parts of the program that cannot be fixed in this manner.
flush
Fixes a problem flushing downloaded data to disk in certain situations. If you have downloaded any torrents with dnh3-release, please check them with the "-c" option to confirm that all of the data was saved!
console
This fixes my interpretation of the description of the stdarg facility, which is at best unclear in most documentation that I have checked. The problem could cause crashes or incorrect behavior in the new console code.
clock_gettime
This patch emulates the clock_gettime function (well enough for this program's needs) using gettimeofday if clock_gettime is not present in the system libraries. This is needed in order to compile on Mac OSX and can also be used on other systems that do not have this function. (You'll know because configure exits with an error.)
maxfd
This corrects initialization of the maxfd variable in the main loop; the bug can result in abnormally high CPU utilization.
To apply the patch, download the file into the ctorrent source directory and run the command:
     patch < patch-dnh3_update.diff
in that directory. Then re-run configure and make.

Release dnh3

Source distribution
A complete source distribution for all platforms.


Patch for reassign bug

reassign patch
This fixes a potential crash when reassigning a piece for download to a faster peer. It likely only shows itself on memory-constrained systems or particular OSs. With verbose output on, you would see something like this:

     Reassigning 0x81183b8 to 0x8160ef8 (#585)
     Segmentation fault

To apply the patch, download the file into the ctorrent source directory and run the command:

     patch < patch-reassign.diff
in that directory. Then recompile the program.

Release dnh2.2

dnh2.1 to dnh2.2 patch file
A patch file of changes to release dnh2.1 to bring it up to dnh2.2.

Source distribution
A complete source distribution for all platforms.


Release dnh2.1

dnh2 to dnh2.1 patch file
A patch file of changes to release dnh2 to bring it up to dnh2.1.

Source distribution
A complete source distribution for all platforms.


Patch for vfat bug

btfiles patch
This fixes a coding bug in my solution for the vfat filesystem issue. This bug can cause the client to crash when creating a file on any filesystem type; the patch is recommended for all users of release dnh2.

To apply the patch, download the file into the ctorrent source directory and run the command:

     patch < patch-btfiles.cpp.diff
in that directory. Then recompile the program.

Release dnh2
The patch files for this version are significantly larger than in previous releases. It will be faster and easier to just download the patched source distribution below.

dnh1.2 to dnh2 patch file
A patch file of changes to release dnh1.2 to bring it up to dnh2.

Patch file
A patch file of changes to the CTorrent 1.3.4 base.

Patched source
A complete source distribution for all platforms.


Older Versions
Please see the Old Versions page for previous releases and patches.


Resources

CTorrent Home Page
Outdated, but you may find some useful info (particularly the FAQ).

CTorrent SourceForge Project
Hosts the original CTorrent codebase, bug reports, patches, and forum.

Custom CTorrent
A page by the author of the "get1file" patch and other fixes. It contains a custom version and a GUI for CTorrent.

BitTorrent
The official BitTorrent home page.

BitTorrent wiki
Various documentation.

BitTorrent protocol specification (official version)

BitTorrent protocol specification (wiki version)