Copyright (c) 2015-2019 Intel, Inc.  All rights reserved.
Copyright (c) 2017-2018 IBM Corporation.  All rights reserved.
$COPYRIGHT$

Additional copyrights may follow

$HEADER$

===========================================================================

This file contains the main features as well as overviews of specific
bug fixes (and other actions) for each version of PMIx since
version 1.0.

As more fully described in the "Software Version Number" section in
the README file, PMIx typically maintains two separate version
series simultaneously - the current release and one that is locked
to only bug fixes.  Since these series are semi-independent of each
other, a single NEWS-worthy item might apply to different series. For
example, a bug might be fixed in the master, and then moved to the
current release as well as the "stable" bug fix release branch.


2.2.3 -- 15 Aug 2019
----------------------
- PR #1162: Fix race condition when clients fail while in a PMIx
            collective operation
- PR #1163: Fix a compiler warning in atomics on POWER arch
- PR #1165: Add BuildRequires: libevent-devel to spec file
- PR #1180: Remove dependency on C++ compiler for thread detection
- PR #1180: Add detection for Flex when building in non-tarball situations
- PR #1182: configury: use PMIX_ENABLE_DLOPEN_SUPPORT instead of enable_dlopen
- PR #1188: Link libpmix.so to MCA component libraries
- PR #1190: Ensure any cached notifications arrive after reg completes
- PR #1194: Ensure any cached notifications arrive after registration completes
- PR #1209: Update configure logic for clock_gettime
- PR #1213/#1217/#1221: Add configure option "--enable-nonglobal-dlopen"
  If the MCA component libraries should link back to libpmix.so
- PR #1231: SPEC: Allow splitting PMIx in pmix and pmix-libpmi packages
- PR #1253: Preserve user-provided CFLAGS to protect autotools
- PR #1267: Correct dmodex example
- PR #1275: IPv6 IF Read: Buffer Overflow
- PR #1295: Fix comment: IPv6 IF_NAMESIZE
- PR #1296: Allow setup_fork to proceed even if gdds and pnet don't contribute
- PR #1296: Allow servers to pass NULL module
- PR #1297: Provide internal blocking ability to the register/deregister fns
- PR #1298: Add dummy handshake component to psec framework for testing
- PR #1303: Allow jobs to not specify proc-level info
- PR #1304: Provide proc data in cases where host does not
- PR #1305: Add some more values that can be computed
- PR #1308: Add missing tool rendezvous file
- PR #1309: Fix potential integer overflow in regex
- PR #1311: Work around memory bug in older gcc compilers
- PR #1329: Add -fPIC to static builds
- PR #1334: Cache only -W CFLAG entries to fix 32-bit builds
- PR #1341: Do not use '==' in m4 test statements
- PR #1342: Fix if_linux_ipv6_open interface filter
- PR #1344: Remove unnecessary libtool init for c++
- PR #1346: Fix incorrect pointer casts/deref
- PR #1347/#1348: Fix use of gethostname
- PR #1353/#1357: util/environ: use setenv() if available
- PR #1354: Plug a misc memory leak in the pmix_query_caddy_t destructor
- PR #1356: Fix another pointer cast/deref in test suite
- PR #1358: Implement support for class-based info arrays
- PR #1359: Plug misc minor memory leaks
- PR #1369: Fix legacy support for PMI-1
- PR #1370: Cleanup handling of data requests for different nspaces
- PR #1193: Resolve get of proc-specific job-level info from another nspace
- PR #1377: Skip fastpath/dstore for NULL keys
- PR #1379: Change IF_NAMESIZE to PMIX_IF_NAMESIZE and set to safe size
- PR #1385: Check for EINVAL return from posix_fallocate
- PR #1389: Plug misc memory leaks in configure



2.2.2 -- 24 Jan 2019
----------------------
 - Fix a bug in macro identifying system events


2.2.1 -- 18 Jan 2019
----------------------
 - Fix a bug in registration of default event handlers
   that somehow slipped thru testing


2.2.0 -- 17 Jan 2019
----------------------
**** THIS RELEASE MARKS THE STARTING POINT FOR FULL COMPLIANCE
**** WITH THE PMIX v2.2 STANDARD. ALL API BEHAVIORS AND ATTRIBUTE
**** DEFINITIONS MEET THE v2.2 STANDARD SPECIFICATIONS.
 - Add a new, faster dstore GDS component 'ds21'
 - Performance optimizations for the dstore GDS components.
 - Plug miscellaneous memory leaks
 - Silence an unnecessary warning message when checking connection
   to a non-supporting server
 - Ensure lost-connection events get delivered to default event
   handlers
 - Correctly handle cache refresh for queries
 - Protect against race conditions between host and internal library
   when dealing with async requests
 - Cleanup tool operations and add support for connections to
   remote servers.
 - Automatically store the server URI for easy access by client
 - Provide MCA parameter to control TCP connect retry/timeout
 - Update event notification system to properly evict oldest events
   when more space is needed
 - Fix a number of error paths
 - Handle setsockopt(SO_RCVTIMEO) not being supported
 - Pass the tool's command line to the server so it can be returned
   in queries
 - Add support for C11 atomics
 - Fix a bug when registering default event handlers


2.1.4 -- 18 Sep 2018
----------------------
- Updated configury to silence warnings on older compilers
- Implement job control and sensor APIs
- Update sensor support
- Fix a few bugs in the event notification system and provide some
  missing implementation (support for specifying target procs to
  receive the event).
- Add PMIX_PROC_TERMINATED constant
- Properly deal with EOPNOTSUPP from getsockopt() on ARM


2.1.3 -- 23 Aug 2018
----------------------
- Fixed memory corruption bug in event notification
  system due to uninitialized variable
- Add numeric version definition
- Transfer all cached data to client dstore upon first connect


2.1.2 -- 6 July 2018
----------------------
- Added PMIX_VERSION_RELEASE string to pmix_version.h
- Added PMIX_SPAWNED and PMIX_PARENT_ID keys to all procs
  started via PMIx_Spawn
- Fixed faulty compares in PMI/PMI2 tests
- Fixed bug in direct modex for data on remote node
- Correctly transfer all cached job info to the client's
  shared memory region upon first connection
- Fix potential deadlock in PMIx_server_init in an error case
- Fix uninitialized variable
- Fix several memory and file descriptor leaks


2.1.1 -- 5 Mar 2018
----------------------
- Fix direct modex when receiving new nspace
- Resolve direct modex of job-level info
- Fix a bug in attribute configuration checks
- Fix a couple of bugs in unpacking of direct modex job-level data
- Correcly handle application setup data during "instant on" launch
- add a PMIX_BYTE_OBJECT_LOAD convenience macro
- Fix two early "free" bugs
- Add an example PMI-1 client program


2.1.0 -- 1 Feb 2018
----------------------
**** NOTE: This release contains the first implementation of cross-version
**** support. Servers using v2.1.0 are capable of supporting clients using
**** PMIx versions v1.2 and above. Clients using v2.1.0 are able to interact
**** with servers based on v1.2 and above.
- Added cross-version communication support
- Enable reporting of contact URI to stdout, stderr, or file (PR #538)
- Enable support for remote tool connections (PR #540, #542)
- Cleanup libevent configure logic to support default install paths (PR #541)
- Debounce "unreachable" notifications for tools when they disconnect (PR #544)
- Enable the regex generator to support node names that include multiple
  sets of numbers


2.0.3 -- 1 Feb 2018
----------------------
- Fix event notification so all sides of multi-library get notified
  of other library's existence
- Update syslog protection to support Mac High Sierra OS
- Remove usock component - unable to support v1.x clients due
  to datatype differences
- Cleanup security handshake
- Cleanup separation of PMI-1/2 libraries and PMIx symbols
- Protect against overly-large messages
- Update data buffer APIs to support cross-version operations
- Protect receive callbacks from NULL and/or empty buffers as this
  can occur when the peer on a connection disappears.
- Fix tool connection search so it properly descends into the directory
  tree while searching for the server's contact file.
- Fix store_local so it doesn't reject a new nspace as that can happen
  when working with tools
- Ensure we always complete PMIx_Finalize - don't return if something
  goes wrong in the middle of the procedure
- Fix several tool connection issues


2.0.2 -- 19 Oct 2017
----------------------
- Update RPM spec file (rpmbuild -ta, and --rebuild fixes) (PR #523)
- Support singletons in PMI-1/PMI-2 (PR #537)
- Provide missing implementation support for arrays of pmix_value_t's (PR #531)
- Remove unsupported assembly code for MIPS and ARM processors
  prior to v6 (PR #547)
- Fix path separator for PMIx configuration files (PR #547)
- Add configure option to enable/disable the default value for the
  show-load-errors MCA param (PR #547)


2.0.1 -- 24 Aug. 2017
----------------------
- Protect PMIX_INFO_FREE macro from NULL data arrays
- Added attributes to support HWLOC shared memory regions
- Fixed several syntax errors in configure code
- Fixed several visibility errors
- Correctly return status from PMIx_Fence operation
- Restore tool connection support and implement search
  operations to discover rendezvous files


2.0.0
------
**** NOTE: This release implements the complete PMIX v2.0 Standard
**** and therefore includes a number of new APIs and features. These
**** can be tracked by their RFC's in the RFC repository at:
**** https://github.com/pmix/RFCs. A formal standards document will
**** be included in a later v2.x release. Some of the changes are
**** identified below.
- Added the Modular Component Architecture (MCA) plugin manager and
  converted a number of operations to plugins, thereby allowing easy
  customization and extension (including proprietary offerings)
- Added support for TCP sockets instead of Unix domain sockets for
  client-server communications
- Added support for on-the-fly Allocation requests, including requests
  for additional resources, extension of time for currently allocated
  resources, and return of identified allocated resources to the scheduler
  (RFC 0005 - https://github.com/pmix/RFCs/blob/master/RFC0005.md)
- Tightened rules on the processing of PMIx_Get requests, including
  reservation of the "pmix" prefix for attribute keys and specifying
  behaviors associated with the PMIX_RANK_WILDCARD value
  (RFC 0009 - https://github.com/pmix/RFCs/blob/master/RFC0009.md)
- Extended support for tool interactions with a PMIx server aimed at
  meeting the needs of debuggers and other tools. Includes support
  for rendezvousing with a system-level PMIx server for interacting
  with the system management stack (SMS) outside of an allocated
  session, and adds two new APIs:
  - PMIx_Query: request general information such as the process
    table for a specified job, and available SMS capabilities
  - PMIx_Log: log messages (e.g., application progress) to a
    system-hosted persistent store
  (RFC 0010 - https://github.com/pmix/RFCs/blob/master/RFC0010.md)
- Added support for fabric/network interactions associated with
  "instant on" application startup
  (RFC 0012 - https://github.com/pmix/RFCs/blob/master/RFC0012.md)
- Added an attribute to support getting the time remaining in an
  allocation via the PMIx_Query interface
  (RFC 0013 - https://github.com/pmix/RFCs/blob/master/RFC0013.md)
- Added interfaces to support job control and monitoring requests,
  including heartbeat and file monitors to detect stalled applications.
  Job control interface supports standard signal-related operations
  (pause, kill, resume, etc.) as well as checkpoint/restart requests.
  The interface can also be used by an application to indicate it is
  willing to be pre-empted, with the host RM providing an event
  notification when the preemption is desired.
  (RFC 0015 - https://github.com/pmix/RFCs/blob/master/RFC0015.md)
- Extended the event notification system to support notifications
  across threads in the same process, and the ability to direct
  ordering of notifications when registering event handlers.
  (RFC 0018 - https://github.com/pmix/RFCs/blob/master/RFC0018.md)
- Expose the buffer manipulation functions via a new set of APIs
  to support heterogeneous data transfers within the host RM
  environment
  (RFC 0020 - https://github.com/pmix/RFCs/blob/master/RFC0020.md)
- Fix a number of race condition issues that arose at scale
- Enable PMIx servers to generate notifications to the host RM
  and to themselves


1.2.5 -- 1 Feb 2018
----------------------
- Fix cross-version issue when v1.2 client interacts with v2.1 server (PR #564)
- Update client connection for cross-version support (PR #591)
- Fix write memory barrier ASM for PowerPC (PR #606)
- Add protection from overly-large messages


1.2.4 -- 13 Oct. 2017
----------------------
- Silence some unnecessary warning messages (PR #487)
- Coverity fix - TOCTOU (PR #465)
- automake 1.13 configure fix (PR #486)
- Update RPM spec file (rpmbuild -ta, and --rebuild fixes) (PR #523)
- Support singletons in PMI-1/PMI-2 (PR #537)


1.2.3 -- 24 Aug. 2017
----------------------
- Resolve visibility issues for public APIs (PR #451)
- Atomics update - remove custom ASM atomics (PR #458)
- Fix job-fence test (PR #423)
- Replace stale PMIX_DECLSPEC with PMIX_EXPORT (PR #448)
- Memory barrier fixes for thread shifting (PR #387)
- Fix race condition in dmodex (PR #346)
- Allow disable backward compatability for PMI-1/2 (PR #350)
- Fix segv in PMIx_server_deregister_nspace (PR #343)
- Fix possible hang in PMIx_Abort (PR #339)


1.2.2 -- 21 March 2017
----------------------
- Compiler fix for Sun/Oracle CC (PR #322)
- Fix missing include (PR #326)
- Improve error checking around posix_fallocate (PR #329)
- Fix possible memory corruption (PR #331)


1.2.1 -- 21 Feb. 2017
----------------------
- dstore: Fix data corruption bug in key overwrite cases
- dstore: Performance and scalability fixes
- sm: Use posix_fallocate() before mmap
- pmi1/pmi2: Restore support
- dstore: Fix extension slot size allocation (Issue #280)


1.2.0 -- 14 Dec. 2016
----------------------
- Add shared memory data storage (dstore) option. Default: enabled
  Configure option: --disable-dstore
- PMIx_Commit performance improvements
- Disable errhandler support
- Keep job info in the shared memory dstore
- PMIx_Get performance and memory improvements

1.1.5
-----
- Add pmix_version.h to support direct detection of PMIx library version
- Fix support for Solaris 10 by using abstract version of strnlen
- Fix native security module for Solaris by using getpeerucred in
  that environment
- Ensure man pages don't get installed in embedded builds
- Pass temporary directory locations in info keys instead of
  the environment

1.1.4
-----
- Properly increment the reference count for PMIx_Init
- Fix examples so all run properly
- Fix/complete PMI2 backward compatibility support to handle
  keys that are not associated with a specific rank
- Do a better job of hiding non-API symbols
- Correct handling of semi-colon terminations on macros.
  Thanks to Ashley Pittman for the patch
- Add more man pages
- Improve error checking and messages for connection
  attempts from client to server
- If the tmpdir name is too long, provide an appropriate
  help message to the user (particularly relevant on
  Mac OSX). Thanks to Rainer Keller for the patch.
- Fix some C++ compatibility issues
- Fix/complete PMI-1 backward compatibility support
- Do not install internal headers unless specifically
  requested to do so
- Add support for multiple calls to Put/Commit


1.1.3
-----
- Update the symbol hiding file to cover all symbols
- Fix examples and test directory Makefile.am's so
  the Makefiles are automatically built and the
  code compiled, but not installed
- Do not install the pmix library in embedded use-cases


1.1.2
-----
- Provide a check for hwloc support - if not found, then
  don't pass any topology info down to the client as it
  won't know how to unpack it anyway.
- Fix a few places where thread safety wasn't provided
- Fix several issues identified by Paul Hargrove:
    * PMIx_Init(NULL) is supported
    * Incomplete PMIx_constants man page had some lingering cruft
    * Missing prototype for pmix_value_load
- Fix race condition in PMIx_Get/PMIx_Get_nb
- Fix double-free error in pmix_server_commit.
- Fix PMIX_LOAD_BUFFER to be safe.


1.1.1
-----
- Fix an issue where the example and test programs
  were incorrectly being installed. Thanks to Orion
  Poplawski for reporting it


1.1.0
-----
- major update of APIs to reflect comments received from 1.0.0
  non-production release
- fixed thread-safety issues
- fixed a range of pack/unpack issues
- added unit tests for all APIs


1.0.0
------
Initial public release of draft APIs for comment - not production
intended
