June 20, 2003 Ver 3.17.1
----------------------------
Bugfixes:
*) Fix memory corruption and crash with groups of large size.
*) Correct make install so it installs header files.
*) Fix syntax error in build.xml file for Java/Ant.
*) Cleanup prototypes to remove compiler warnings.
*) Fix parser to correctly recognize upper, lower, and mixed case command options.
*) During make install, remove old symlinks.
*) Change setgroups call to be more portable. (fixes MacOSX)
*) Change name of r and s to sprecv and spsend, and add as make targets. 
   They can be built by "make testprog" (not built by default).
*) Work on making long group names possible. 
*) Increase listen backlog for accepting client connections.
*) Fix Win32 project files to have correct path to source files. 
   (note CVS was always ok, but 3.17.0 release had incorrect path)
*) Fix bug where large groups overflow Mess_buf in groups.c.
*) Fix memory corruption bug when a message header is received in
   several separate packets in session.c. Thanks to Ryan Caudy for 
   many, many hours tracking this down.
*) Change order of build in Makefile so binaries are built before
   documentation.
*) Fix Java bug where connection objects cannot be disconnected and
   then reconnected, but must be created anew. They can now be reused.
*) Fix compile error on AIX for struct if_info.
*) Fix security issue with buffer checks in the C library. 
*) Fix obscure off-by-one buffer error with the parser. 

September 25, 2002 Ver 3.17.0
----------------------
Features:
1) Apply Daniel Rall's SO_REUSEADDR patch. This adds a new configuration
   option SocketPortReuse that can either force SO_REUSEADDR on or off
   for TCP server sockets, or set it to an auto mode that uses REUSEADDR
   if specific interfaces are specified in the spread.conf file and
   does not use it if the default of INADDR_ANY is used. If you force
   this on, be aware that it can open up a security risk where other
   processes can steal Spread's traffic.
2) Enhance the group membership algorithm so very large groups and very large
   numbers of groups will be merged correctly during a membership. 
   With this change Spread should correctly handle groups with thousands
   of members and thousands of groups. This also includes a slight 
   optimzation by sending groups messages as AGREED instead of SAFE.
   Thanks to Ryan Caudy from JHU for doing this work.
3) Revamped build setup using autoconf instead of manual Makefiles. Thanks
   to Theo Schlossnagle for writing this and updating it. Some small changes
   were made to Theo's 3.16.2 patch when I applied it.
4) Change library name from libsp to libspread. This is both more descriptive
   and should fix the problem with library clashes with other libsp's.
5) Apply Daniel Rall's patch to make the spread execution directory and
   the user and group it runs as configurable at runtime.

Bugfixes: 
6) Make sure service_type is set to 0 before using it in SP_receive calls 
   in sample programs (spuser, spflooder, simple_user).
7) Fix GGT bug where Spread gets stuck or crashes if you reach GGT state.
8) Fix Mem_Alloc blocks so they can be freed without assertion failure.
9) Fix hanging bug where token rotates, but ARU is stuck.

Documentation:
10) Split the growing changelog at the beginning of Readme.txt into a 
    separate file.
11) Updates to man pages. Clarify service_type handling. Add info on accessor
    functions for membership message body.

April 2, 2002 Ver 3.16.2 (The Almost April Fools Release)
---------------------------
Bugfixes:
1) All recv calls in session now check for EWOULDBLOCK, EAGAIN, EINTR 
   and retry the call later. This fixes problem on busy servers where 
   connections would be killed erroneously. Thanks to the Zope team 
   (Guido van Rossum, Tim Peters, and Jeremy Hylton) for discovering this
   and helping with fixing it.
2) log.c file operations now check for errors and handle them.
3) Windows bugs:
   a) close() does not close sockets, we need to call closesocket() to avoid
      memory leak.
   b) sockets are not consecutive fd's on windows, they can be > FD_SETSIZE.
      So fd mapping to sessions changed to use a hash instead of array. 
      As a side-effect it should be faster to connect/disconnect. 
      Thanks to Marc Zyngier for discovering the problem and writing and 
      testing a patch for it.
   c) Raise the FD_SETSIZE for windows to 1024 by #defining it in arch.h.
   d) Enhanced error handling to support WSAGetLastError, and define a
      sock_strerror() function to return nice error strings on windows.
   e) Include Visual C++ Project files to build Spread on Windows.
4) Included improved NetBSD makefile and warning fix from Patrick Welche.
5) Generalize the errno handling to support windows errors and other 
   odd cases. Also see fix 3d. Thanks to Marc Zyngier, Tim Peters, and
   David Holmer for help with this.
6) Improve the install targets for linux. Now install include headers
   and use standard PREFIX define for base directory.
7) Updates to man pages. New libsp manpage.

December 11, 2001 Ver 3.16.1  
------------------------
Bugfixes:
1) Fix various races and bugs in the new authentication and access control 
   code. 
   a) Fix session establishment races with authentication
   b) Add more info for access control hooks to use (mess_type and num_groups)
   c) Fix so rejected messages are not still delivered to local group members.
   d) Make reject messages honor SELF_DISCARD.
   e) Fix bug that always allowed NULL connections.
2) SGI now builds using signed chars and reports errors correctly.
3) MacOSX build fixed. 
4) Fixed race at session establishment that caused the assertion failure
   "assert( xxxxx ) false "
5) Add MAX_MESSAGE_BODY_LEN to spread_params.h (used in sp.c checks), move
   MAX_PACKET_SIZE to spread_params.h from arch.h.
6) Fixed interface restrictions for daemons. 
7) Fixed crashes in user and flooder programs when wrong number of command
   line parameters were passed.
8) Added assertion check for Groups membership message with zero members in a group. (Theo)
9) Java library fixes and enhancements (Thanks to Dan Rall and Leonard
	Richardson )
10) Fix bug in group name validator G_private_to_names that caused crash.
11) Fix for reversed parameters to memset in groups.c (Thanks to Marc Zyngier)
12) Fix bug in session connection that confused closed, but not yet deleted file 
    descriptors with newly accepted connections. (Thanks to Dave Parker for discovering bug).
13) Fix significant memory leak when connections are disconnected. This
    leak has been present since at least 3.15.0. (Thanks to Dave Parker
    for discovering this and providing lots of assistance debugging it.)
14) Fix the binding to specific interfaces to work with broadcast packets. 
    (Thanks to Marc Zyngier for reporting the problem)
15) Updated man pages and Users Guide
16) Added makefile for OpenBSD contributed by Brandon Palmer.
17) Added makefile for Solaris 8 with Solaris cc compiler 6.1 contributed by Luc I. Suryo.


June 25, 2001 Ver 3.16.0
-------------------------
Changes:
1) Add support for configuring multiple interfaces on daemons. Each daemon
   can now choose which interfaces to listen on for client connections, monitor
   requests, and daemon-to-daemon communication.
2) Added support for MacOSX. Thanks to Julien Defour and Dirk-Willem van Gulik.
3) Agreed messages for join/leave instead of SAFE messages.
4) Fixed bug with membership messages for more then 42 members in a group.
5) Document how to monitor packing effectiveness.
6) SP_connect assigns unique private name if user gives a zero length string as
   the user name.
7) Slightly loosen valid field checking for service_type field to allow
   flush and secure spread libraries to work.
8) Fix events to work with low priority events for Splash.
9) Adds modular access control and authentication system that allows the 
   daemon to authenticate client connections and allow or disallow various
   actions (such as joining groups, sending messages or connecting) based
   on the authenticated user. This changes the client-server network
   protocol, but is backward compatible with clients linked with old libraries.
   This also adds new functions to the API. A sample module that
   provides access control based on the IP address of the client is 
   included. Also a module that provides the same "allow all clients" 
   policy as older versions of Spread. The Java API has also been 
   updated to support the new access control framework.
10) New license for Spread. BSD based open-source license.
11) Updated Perl library with some bug fixes and compatibility with new C lib.
12) Added support for 64 bit platforms (alpha, ultrasparc & ia64) Note only
    alpha is actually tested.
13) Fix bug in sp.c where if a message was not completely received because 
    of a short buffer and the next call had an invalid message scatter the
    data in the messages would get corrupted. Probably difficult to trigger 
    unless you are trying hard.
14) Changed names of programs included with spread to have "sp" as a prefix.
    This should help avoid conflicts with all the other utilities called 
    "user" or "monitor".
15) Small bugfixes to the Java library. 
16) Bugfix which removes a costly, and unnecessary, recalculation when 
    several network level membership events occur in close (time) proximity.
 
March 20, 2001 Ver 3.15.2
-------------------------

Changes:
1) Bugfix to java library to fix exception caused when trying to establish
   connection. This is a new bug in 3.15.1. Thanks to Julien Dufour.
2) Add #define SPREAD_VERSION to sp.h so client applications can test for
   what version of the spread API to use. This allows applications to compile
   against multiple incompatible versions of the spread library. Specifically,
   this can be used for an app to support both the old 'float SP_version()'
   and new 'int SP_version(int, int, int)' functions.
3) Fix memory leak in Perl module. Thanks to Theo Schlossnagle.

February 26, 2001 Ver. 3.15.1
-----------------------------
Changes:
1) Make sess_read() non-blocking so slow clients sending messages don't slow
   or block daemon.
2) Implement input validation on all messages received from clients. This
   is to address the possibility of clients overflowing the servers buffers.
   These problems were uncovered in a security audit by Olaf Kirch of Caldera.
3) Use chroot to isolate spread and drop priveledges if spread is run by root.
   If it is run as a normal user, then no chroot is done and it runs just as 
   before. The user to run as and the location of the chroot jail can be 
   configured in the spread_params.h file at compile time.
4) Fix a bug that causes a significant memory leak when retransmissions are 
   required. This memory leak exists in versions 3.13, 3.14 and 3.15.0.
5) SP_version() no longer returns a float, instead it returns in 3 separate
   parameters the 3 components of the version number.
 
December 20, 2000 -- Unreleased 3.15.0
-----------------
Changes:
1) New version number scheme with 3 components: Major, Minor, and Patch.
2) Small bugfix to prevent clients from sending to too many groups and
   crashing spread.
3) Copyright changed to Spread Concepts LLC for code by original
   developers.

0ctober 31, 2000 
---------------
Changes:
1) Bugfixes to skiplist implementation.
2) Critical fixes to group membership that removes bugs introduced in 
   optimization work of 3.13.
3) Critical bugfix to membership which solves problem introduced in 3.13 
   with using configurations of more then one segment.
4) Changes to spread.conf parser, but nothing that should be user visable.
5) Better error/problem reporting in a few cases.
6) Enforce message length limit. SP_mcast* will now return an error
   if a message body is too long.
7) Minor memory leak at initialization fixed.
8) Fix to events.c to prevent an illegal message bug. Bug is triggered
   when messages are sent very fast during a membership merge.

August 07, 2000
---------------
Changes:
1) To compile the Linux version on systems based on glibc2.0 (such as 
   RedHat 5.2) you need to comment out the #define of HAVE_STDINT_H in the 
   arch.h file before compiling.

2) Major scalability improvements. Should now support upto 990 connections
   to each daemon, thousands of groups, and faster throughput with
   small messages.

3) Configuration file changes. 
	a) The default name of the configuration file 
	   has changed from config.dat to spread.conf. The default locations 
	   checked if nothing is specified on the command line is 
	   /etc/spread.conf and ./spread.conf (i.e. the current directory 
	   where the binary is run from).
	b) The format of the spread.conf file is improved. You no longer
	   have to specify the number of members of a segment or the number
	   of segments by hand. The format is also more standard and has a 
	   lex/yacc grammer defining it. See the sample.spread.conf file 
	   for an example or the documention for details.
	c) More configuration variables. 
		EventLogFile: You can now have all the Spread event messages 
			      that print to the screen print to a file instead.
			      To have each daemon log to a separate file use the
			      '%h' or '%H' special characters in the log filename.
			      Spread will replace those characters with the hostname
			      of the machine which the daemon is running on. An 
			      example can be found in the sample.spread.conf file.
		DebugFlags: The event mask that determines which messages
			    to print to the screen is now configurable at
			    runtime.
		EventTimeStamp: Add a timestamp in front of all logged event 
				messages and set the format of the timestamp.

		DangerousMonitor: Certain monitor commands like partition, kill
				  and flow_control are disabled by default now.
				  To enable them set this to true.

4) Fix membership bug when under high load and a late data message arrives.
   Also fix membership bug where the assertion 
"spread: membership.c:1835: Backoff_membership: Assertion `pack_entry != -1' failed."
   triggered.
   Also fix membership bug where several machines will get trapped in 
   State 3 (GATHER state) and will never complete the membership.

5) Some documentation on how to tune Spread using some of the internal variables.
   This is contained in the new Spread User Guide Chapter 2 which can be 
   downloaded from www.spread.org.

6) Fix bug in new No Drop semantics. When a BUFFER_TOO_SHORT error occured
   the endian_mismatch field was incorrectly set to the size of the app buffer
   instead of the size of the data message. So it was useless. This is fixed and
   the semantics are extended to set the num_groups and endian_mismatch fields to 0
   if the corresponding buffers ARE large enough, and to the needed size 
   (as a negative) when they are NOT large enough. This allows you to know when 
   you receive a GROUPS_TOO_SHORT whether the buffer is also too short without 
   any calculation...Just check if endian_mismatch is 0.

7) License updated to version 1.2. The only change is a small addition to the
   attribution requirement, a capitalization of Spread, and a clarification of
   the Spread version.

May 01, 2000
---------------
Changes:
1) Integrated FreeBSD port. A Big thanks to Ben Laurie <ben@algroup.co.uk>
   for this port and a lot of compile warnings, type cleanups and 2 bugfixes.

2) Removed some compile warnings.

3) 2 bugs fixed. One in SP_group_ids_equal() and one in the 
   daemon that would never trigger in reality.

4) Updated java interface to most recent version.

5) Updated events (E_* functions) to most recent version. This
   adds the ability to attach to file descriptors for 
   Exceptions and Write events as well as reads. It also 
   adds a void* data pointer to the callback parameters.

6) Change SP_recv semantics to be "No Drop" by default. The 
   old "drop" semantics are still available by setting the 
   service_type parameter to SP_recv to DROP_RECV before calling it.
   *** 
   See the file "Short_Buffer_Handling.txt" for detailed comments
   on this change and what application modifications might be necessary
   ***

7) Documentation updates.

8) Changed the way arch.h is implemented. This might require 
   some additions for Ports that we do not support natively.

9) Added Is_self_leave() macro which matches documentation for testing
   self-leaves.

10) Changed SP_* and E_* functions to use 'const' appropriately.

11) Reserved fields are listed in sp.h to prevent collisions.

12) Make MAX_PROC_NAME and MAX_PRIVATE_GROUP sizes available in sp.h.

13) Added Perl library interface. You can now write Spread client 
    programs in perl. Thanks to Theo Schlossnagle <theos@cnds.jhu.edu>.

14) License updated to version 1.1. Main change is a reformatting and 
    updated email addresses. 

July 27, 1999 Official Release
---------------------------------------------------

1) Has new license (license.txt) and copyright notices

2) New Java interface included

3) Location of license has moved to: 
	    http://www.spread.org/license/
	    http://www.cnds.jhu.edu/spread/license/

4) Minor documentation and example program improvements.

5) One minor bug fixed in group handling.

May 26, 1999 Release:
---------------------
1) Expiration Date Removed from Binary version
   This release of the executatbles will not expire.

2) New Copyright Statement
   The copyright of Spread has been finalized. The statement at the top of 
   this file shows it.

3) Source release soon & new license
   a) As soon as a few final issues are resolved we will release the source
      to Spread under the CNDS Non-Commercial and Development License. 
   b) A draft of the new license can be found at 
      http://www.cnds.jhu.edu/spread/CNCL/.
      Please email us any comments or concerns you have at spread@spread.org

4) Bugs Fixed:
   a) Bug fix to the SP_scatter_recv() call to make receives into 
      scatter structures of multiple entries of different sizes work.
   b) The Linux platform also had scatter-gather functionality enabled 
      (now that glibc has working sendmsg, recvmsg calls)
   c) Fixed bug where packets which are delayed a long time in the network
      but then actually arrive at a spread daemon cause a crash.


October 30,1998 Release:
-----------
1) Multi-threading:
   Libsp.a has split into two libraries, libsp.a and libtsp.a, they
   are identical except that libtsp.a is thread-safe and libsp.a is not.
   Both versions are provided so that single-threaded programs who don't 
   need a safe library can avoid the (admittedly pretty small) overhead of 
   locking. The libtsp.a can be used identically with libsp.a with the 
   addition that all SP_* functions can be called by multiple threads 
   at the same time.  Thread safety in libtsp.a is provided optimally,
   with the most possible parallelism allowed.  Threads acting on separate
   mailboxes will never block each other, threads writing to a mailbox will
   never block other threads reading from the same mailbox and vice versa.
   The one time thread calls to SP_ functions will be serialzed is when 
   multiple threads are reading the same mailbox or writing the same mailbox.
   There is minimal locking of internal structures which can temporarily 
   block another thread, but since a thread never blocks while in one of 
   these structure critical sections and the duration of the lock is at 
   most a fewinstructions the delay should be minimal.  
   
2) IP-Multicast:
   Spread now allows you to specifiy IP-Multicast addresses(i.e. 224.0.0.1) 
   as the broadcast address for a segment in the spread.conf file. This will 
   work transparently in the same segment, and is guaranteed not to spill 
   multicast packets beyond that segment. If multi-segment ip-multicast is 
   desired, please contact us.

3) Fixed several minor bugs.

4) Included man pages for SP functions. The old html documentation is also 
   included.

5) None of these changes effect the Java version which has not changed.