1 Megaco Release Notes

This document describes the changes made to the Megaco system from version to version. The intention of this document is to list all incompatibilities as well as all enhancements and bugfixes for every release of Megaco. Each release of Megaco thus constitutes one section in this document. The title of each section is the version number of Megaco.

1.1 Megaco 3.15.1

Version 3.15.1 supports code replacement in runtime from/to version 3.15, 3.14.1.1, 3.14.1 and 3.14.

Improvements and new features

Fixed bugs and malfunctions

Fixing miscellaneous things detected by dialyzer.

Own Id: OTP-9075

1.2 Megaco 3.15

Improvements and New Features

Fixing auto-import issues.

Own Id: OTP-8842

Fixed bugs and malfunctions

1.3 Megaco 3.14.1.1

Version 3.14.1.1 supports code replacement in runtime from/to version 3.14.1, 3.14, 3.13, 3.12 and 3.11.3.

Improvements and new features

Updated the performance chapter.

Own Id: OTP-8696

Fixed bugs and malfunctions

1.4 Megaco 3.14.1

Version 3.14.1 supports code replacement in runtime from/to version 3.14, 3.13, 3.12 and 3.11.3.

Improvements and new features

A minor compiler related performance improvement.

Own Id: OTP-8561

Fixed bugs and malfunctions

A race condition when, during high load, processing both the original and a resent message and delivering this as two separate messages to the user.

Note that this solution only protects against multiple reply deliveries!

Own Id: OTP-8529

Aux Id: Seq 10915
Fix shared libraries installation.

The flex shared lib(s) were incorrectly installed as data files.

Peter Lemenkov

Own Id: OTP-8627
Eliminated a possible race condition while creating pending counters.

Own Id: OTP-8634

Aux Id: Seq 11579

1.5 Megaco 3.14

Version 3.14 supports code replacement in runtime from/to version 3.13, 3.12 and 3.11.3.

Improvements and new features

Various changes to configure and makefile(s) to facilitate cross compilation (and other build system improvements).

Own Id: OTP-8323
Added a help target in the test Makefile to explain the most useful make targets, used when testing the application using the test-server provided with megaco.

Own Id: OTP-8362
Adapted megaco_filter to the new internal format.

Own Id: OTP-8403

Fixed bugs and malfunctions

Callbacks, when the callback module is unknown (undefined), results in warning messages.

A race condition scenario. As part of a cancelation operation, replies with waiting acknowledgements is cancelled. This includes informing the user (via a call to the handle_trans_ack callback function). It is possible that at this point the connection data has been removed, which makes it impossible for megaco to perform this operation, resulting in the warning message. The solution is to also store the callback module with the other reply information, to be used when cleaning up after a cancelation.

Own Id: OTP-8328

Aux Id: Seq 11384

1.6 Megaco 3.13

Version 3.13 supports code replacement in runtime from/to version 3.12 and 3.11.3.

Improvements and new features

A minor optimization by using ets:update_element instead of ets:insert for some table updates.

Own Id: OTP-8239
The documentation is now built with open source tools (xsltproc and fop) that exists on most platforms. One visible change is that the frames are removed.

Own Id: OTP-8249

Fixed bugs and malfunctions

Incompatibilities

1.7 Megaco 3.12

Improvements and new features

Improve handling of async transaction reply.

For asynchronous requests, issued using megaco:cast/3, the reply will be delivered using the handle_trans_reply/4,5 callback function.

If a receiver of a request, issued using megaco:cast/3, does not reply in time, megaco re-sends the request. If the receiver of the request sends the reply at the same time as megaco re-sends, it may also send a reply to the resent request (thinking the first reply got lost). These two replies may arrive more or less at the same time, causing confusion.

In order to improve this situation, a number of improvements have been done:
- When the first reply arrives, a timer, request-keep-alive, is started. This timer is used to decide when to stop accepting replies as legitimate.
  
  The timeout time for the timer is specified by the config option request_keep_alive_timout, which can be set per user or per connection.
- We also keep track of how many replies has been received (we do this as long as the request-keep-alive timer is running).
- Each reply that arrives while the request-keep-alive timer is running (including the first) will be delivered using the handle_trans_reply/4,5 callback function, but with the UserReply augmented to include a serial number indicating which reply number this is. The first reply to arrive, will be numbered one (1).
- Replies arriving after the timer has expired will be delivered in the same way as before, using the handle_unexpected_trans/3,4 callback function.
- Note that if the timer was not configured, megaco will act exactly as before!
Own Id: OTP-8183

Aux Id: Seq 11393

Fixed bugs and malfunctions

If the megaco app received a transaction reply, for a request issued using the call/3 function, from the wrong remote entity (wrong MId)), megaco would still deliver the reply (call/3 returnes) as if from the correct remote entity (right MId).

This has been changed so that the function now returns with an error reason.

See call/3 for more info.

*** POTENTIAL INCOMPATIBILITY ***

Own Id: OTP-8212

Aux Id: Seq 11305

1.8 Megaco 3.11.3

Improvements and new features

Replacing obsolete guard tests.

Own Id: OTP-8164
Added the config option call_proxy_gc_timeout to be able to control the way unexpected replies (when requests issued via calls to call/3) are handled.

See user_info/2, conn_info/2 and call/3 for more info.

Own Id: OTP-8167

Aux Id: Seq 11393
Make flex scanner c89 compiler compliant.

Akira Kitada

Own Id: OTP-8191

Fixed bugs and malfunctions

Incompatibilities

1.9 Megaco 3.11.2

Version 3.11.2 supports code replacement in runtime from/to version 3.11.1 and 3.11.

Improvements and new features

Megaco was unnecessarily strict when parsing the SDP attribute maxptime (leading or trailing spaces cased the value parse to fail).

This has been improved so that leading and trailing spaces are stripped before parsing the value. The same has been done for the attribute ptime.

Own Id: OTP-8123

Aux Id: Seq 11364

Fixed bugs and malfunctions

Incompatibilities

1.10 Megaco 3.11.1

Version 3.11.1 supports code replacement in runtime from/to version 3.11.

Improvements and new features

Fixed bugs and malfunctions

[text] The unquoted string BOTH was interpreted as the 'BothToken' token. This was a version 3 (prev3a, prev3b, prev3c and v3) only.

Own Id: OTP-8114

Aux Id: Seq 11353
The reply proxy could crash if the timeout time calculation results in a negative number. This will result in a function clause with resulting error report.

Own Id: OTP-8081

Aux Id: Seq 11332

Incompatibilities

1.11 Megaco 3.11

Improvements and new features

In order to better utilize multi-core procs, the flex (text) scanner has been improved.

The flex (text) scanner has been made reentrant, if the flex utility supports this. Note that the version of flex supplied with some OS/distros (Solaris 10, FreeBSD and OpenBSD to mention a few) may not support this, in which case the flex scanner will be non-reentrant, just as before.

Own Id: OTP-7302

Fixed bugs and malfunctions

Incompatibilities

1.12 Megaco 3.10.1

Version 3.10.1 supports code replacement in runtime from/to version 3.10.0.1, 3.10 and 3.9.4.

Improvements and new features

Fixed bugs and malfunctions

Unexpected handle_unexpected_reply callbacks.

The megaco_user callback function handle_unexpected_reply could during high load be called with unexpected values for the Trans argument, such as an TransactionReply where transactionResult had the value {error, timeout}. This was a result of a race condition and has now been fixed.

Own Id: OTP-7926

Aux Id: Seq 11255
[text] PropertyParm values cannot be quoted.

It was not possible to encode a PropertyParm value as a quoted string (unless it *had* to (has at least one RestChar)). The megaco text codec's now also accepts quoted strings as PropertyParm values.

Own Id: OTP-7936

Aux Id: Seq 11258

Incompatibilities

1.13 Megaco 3.10.0.1

Version 3.10.0.1 supports code replacement in runtime from/to version 3.10 and 3.9.4 except when using any of the drivers (flex for text or asn1 for binary).

Improvements and new features

Updated file headers.

Own Id: OTP-7851

Fixed bugs and malfunctions

Incompatibilities

1.14 Megaco 3.10

Version 3.10 supports code replacement in runtime from/to version 3.9.4, 3.9.3, 3.9.2, 3.9.1.1, 3.9.1, 3.9, 3.8.2, 3.8.1 and 3.8 except when using any of the drivers (flex for text or asn1 for binary).

Improvements and new features

Added new API function megaco:connect/5 and the corresponding new megaco_user callback function handle_connect/3. The purpose of this is to be able to pass information to the handle_connect/3 function by calling the megaco:connect/5 function.

Own Id: OTP-7713

Aux Id: Seq 11140
Update file headers with new copyright notice.

Own Id: OTP-7743

Fixed bugs and malfunctions

Incompatibilities

If the transport module calls the process_received_message/5 or receive_message/5 function(s) for the initial message, then the handle_connect/3 function will now be called and not the handle_connect/2 function.

Own Id: OTP-7713

Aux Id: Seq 11140