epics-base/documentation/RELEASE-3.15.md

Changes incorporated from the 3.15 branch

Changes from the 3.15 branch since 3.15.9

Support for Apple M1/M2 (arm64) Processors

Thanks to Jeong Han Lee this release comes with build support for Apple's new M1/M2 CPUs running macOS, using the target name darwin-aarch64.

Set thread names on Windows

On MS Windows, epicsThread names are made available to the OS and debugger using SetThreadDescription() if available as well as using the older exception mechanism.

Fix timers on MS Windows for non-EPICS threads

The waitable timer changes in 3.15.9 broke calls to epicsThreadSleep() and similar routines that used timers (including ca_pend_event()) when made from threads that were not started using the epicsThread APIs. This problem has now been fixed.

Changes made between 3.15.8 and 3.15.9

Use waitable timers on Microsoft Windows

The epicsEventWaitWithTimeout() and epicsThreadSleep() functions have been changed to use waitable timers. On Windows 10 version 1803 or higher they will use high resolution timers for more consistent timing.

See this Google Groups thread for a comparison of the performance of different timers.

Build target for documentation

The build target inc now works again after a very long hiatus. It now generates and installs just the dbd, header and html files, without compiling any C/C++ code. This can be used to speed up CI jobs that only generate documentation.

Bug fixes

• The error status returned by a record support's special() method is now propagated out of the dbPut() routine again (broken since 3.15.0).
• gh: #80, VS-2015 and later have working strtod()
• lp: #1776141, Catch buffer overflow from long link strings
• lp: #1899697, Records in wrong PHAS order

Change to the junitfiles self-test build target

The names of the generated junit xml test output files have been changed from <testname>.xml to <testname>-results.xml, to allow better distinction from other xml files. (I.e., for easy wildcard matching.)

Fixes and code cleanups

Issues reported by various static code checkers.

Changes made between 3.15.7 and 3.15.8

Bug fixes

The following launchpad bugs have fixes included in this release:

• lp: 1812084, Build failure on RTEMS 4.10.2
• lp: 1829770, event record device support broken with constant INP
• lp: 1829919, IOC segfaults when calling dbLoadRecords after iocInit
• lp: 1838792, epicsCalc bit-wise operators on aarch64
• lp: 1841608, logClient falsely sends error logs on all connections
• lp: 1853168, undefined reference to clock_gettime()
• lp: 1862328, Race condition on IOC start leaves rsrv unresponsive
• lp: 1868486, epicsMessageQueue lost messages

Improvements to the self-test build targets

This release contains changes that make it possible to integrate another test running and reporting system (such as Google's gtest) into the EPICS build system. The built-in test-runner and reporting system will continue to be used by the test programs inside Base however.

These GNUmake tapfiles and test-results build targets now collect a list of the directories that experienced test failures and display those at the end of running and/or reporting all of the tests. The GNUmake process will also only exit with an error status after running and/or reporting all of the test results; previously the -k flag to make was needed and even that didn't always work.

Continuous Integration systems are recommended to run make tapfiles (or if they can read junittest output instead of TAP make junitfiles) followed by make -s test-results to display the results of the tests. If multiple CPUs are available the -j flag can be used to run tests in parallel, giving the maximum jobs that should be allowed so make -j4 tapfiles for a system with 4 CPUs say. Running many more jobs than you have CPUs is likely to be slower and is not recommended.

Calc Engine Fixes and Enhancements

The code that implements bit operations for Calc expressions has been reworked to better handle some CPU architectures and compilers. As part of this work a new operator has been added: >>> performs a logical right-shift, inserting zero bits into the most significant bits (the operator >> is an arithmetic right-shift which copies the sign bit as it shifts the value rightwards).

IOC logClient Changes

The IOC's error logging system has been updated significantly to fix a number of issues including:

• Only send errlog messages to iocLogClient listeners
• Try to minimize lost messages while the log server is down:
  • Detect disconnects sooner
  • Don't discard the buffer on disconnect
  • Flush the buffer immediately after a server reconnects

epicsThread: Main thread defaults to allow blocking I/O

VxWorks IOCs (and potentially RTEMS IOCs running GeSys) have had problems with garbled error messages from dbStaticLib routines for some time — messages printed before iocInit were being queued through the errlog thread instead of being output immediately. This has been fixed by initializing the main thread with its OkToBlock flag set instead of cleared. IOCs running on other operating systems that use iocsh to execute the startup script previously had that set anyway in iocsh so were not affected, but this change might cause other programs that don't use iocsh to change their behavior slightly if they use errlogPrintf(), epicsPrintf() or errPrintf().

catools: Handle data type changes in camonitor

The camonitor program didn't properly cope if subscribed to a channel whose data type changed when its IOC was rebooted without restarting the camonitor program. This has now been fixed.

More Record Reference Documentation

The remaining record types have had their reference pages moved from the Wiki, and some new reference pages have been written to cover the analog array and long string input and output record types plus the printf record type, none of which were previously documented. The wiki reference pages covering the fields common to all, input, and output record types have also been added, thanks to Rolf Keitel. The POD conversion scripts have also been improved and they now properly support linking to subsections in a different document, although the POD changes to add the cross-links that appeared in the original wiki pages still needs to be done in most cases.

Fix build issues with newer MinGW versions

The clock_gettime() routine is no longer used under MinGW since newer versions don't provide it any more.

Fix race for port in RSRV when multiple IOCs start simultaneously

If multiple IOCs were started at the same time, by systemd say, they could race to obtain the Channel Access TCP port number 5064. This issue has been fixed.

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Changes made between 3.15.6 and 3.15.7

GNU Readline detection on Linux

Most Linux architectures should now configure themselves automatically to use the GNU Readline library if its main header file can be found in the expected place, and not try to use Readline if the header file isn't present. For older Linux architectures where libncurses or libcurses must also be linked with, the manual configuration of the COMMANDLINE_LIBRARY variable in the appropriate configure/os/CONFIG_SITE.Common.<arch> file will still be necessary.

Replace EPICS_TIMEZONE with EPICS_TZ

The EPICS_TIMEZONE environment parameter provided time-zone information for the IOC's locale in the old ANSI format expected by VxWorks for its TIMEZONE environment variable, and can also used by RTEMS to set its TZ environment variable. However the TIMEZONE value has to be updated every year since it contains the exact dates of the daylight-savings time changes. The Posix TZ format that RTEMS uses contains rules that for calculating those dates, thus its value would only need updating if the rules (or the locale) are changed.

This release contains changes that replace the EPICS_TIMEZONE environment parameter with one called EPICS_TZ and a routine for VxWorks that calculates the TIMEZONE environment variable from the current TZ value. This routine will be run once at start-up, when the EPICS clock has synchronized to its NTP server. The calculations it contains were worked out and donated to EPICS by Larry Hoff in 2009; it is unfortunate that it has taken 10 years for them to be integrated into Base.

The default value for the EPICS_TZ environment parameter is set in the Base configure/CONFIG_SITE_ENV file, which contains example settings for most EPICS sites that use VxWorks, and a link to a page describing the Posix TZ format for any locations that I missed.

If a VxWorks IOC runs continuously without being rebooted from December 31st to the start of daylight savings time the following year, its TIMEZONE value will be wrong as it was calculated for the previous year. This only affects times that are converted to a string on the IOC however and is easily fixed; just run the command tz2timezone() on the VxWorks shell and the calculation will be redone for the current year. IOCs that get rebooted at least once before the start of summer time will not need this to be done.

Added new decimation channel filter

A new server-side filter has been added to the IOC for reducing the number and frequency of monitor updates from a channel by a client-specified factor. The filter's behaviour is quite simplistic, it passes the first monitor event it sees to the client and then drops the next N-1 events before passing another event. For example to sample a 60Hz channel at 1Hz, a 10Hz channel every 6 seconds, or a 1Hz channel once every minute:

    Hal$ camonitor 'test:channel.{"dec":{"n":60}}'
    ...

More information is included in the filters documentation, which can be found in the html/filters.html document that is generated during the build.

Imported Record Reference Documentation from Wiki

The remaining record types that had 3.14 reference documentation in the EPICS Wiki have had that documentation converted and imported into their DBD files. The preferred form for future updates to the record type descriptions is now an emailed patch file, a Pull Request through GitHub, or a Merge Request through Launchpad. Note that in some cases the behavior of a record type in a 7.0.x release may differ from that of the same record type in a 3.15 release, although this would be unusual, so it may be important to indicate the branch that your changes apply to.

NOTE: These documentation changes have modified the order of the fields in some record definitions. As a result this release is not compatible with record or device support binaries that were compiled against earlier releases.

make test-results for Windows

The make target test-results should now work properly on Windows. Some Perl installations used versions of prove.bat that would only display the results of up to 3 tests or didn't return an error status in the event of tests failing. The build system now calls its own perl script to summarize the results instead of passing a list of TAP filenames to prove.

Add option to avoid CALLBACK conflict

If a macro EPICS_NO_CALLBACK is defined, then callback.h will no longer (re)define CALLBACK. The name CALLBACK is used by the WIN32 API, and redefinition in callback.h cause errors if some windows headers are later included.

Code which defines EPICS_NO_CALLBACK, but still wishes to use callbacks, should use the alternate name epicsCallback introduced in 3.15.6, 3.16.2, and 7.0.2. It is also possible, though not encouraged, to use struct callbackPvt which has been present since the callback API was introduced.

Cleaning up with Multiple CA contexts in a Process

Bruno Martins reported a problem with the CA client library at shutdown in a process that uses multiple CA client contexts. The first context that triggers the CA client exit handler prevents any others from being able to clean up because it resets the ID of an internal epicsThreadPrivate variable which is shared by all clients. This action has been removed from the client library, which makes cleanup of clients like this possible.

Perl CA bindings fixed for macOS Mojave

Apple removed some Perl header files from macOS Mojave that were available in their SDK, requiring a change to the include paths used when compiling the CA bindings. The new version should build on new and older macOS versions, and these changes may also help other targets that have an incomplete installation of Perl (the build will continue after printing a warning that the Perl CA bindings could not be built).

Routine epicsTempName() removed from libCom

This routine was a simple wrapper around the C89 function tmpnam() which is now seen as unsafe and causes warning messages to be generated by most modern compilers. The two internal uses of this function have been modified to call epicsTempFile() instead. We were unable to find any published code that used this function, so it was removed immediately instead of being deprecated.

DBD Parsing of Record Types

The Perl DBD file parser has been made slightly more liberal; the order in which DBD files must be parsed is now more flexible, so that a record type definition can now be parsed after a device support that referred to that record type. A warning message will be displayed when the device support is seen, but the subsequent loading of the record type will be accepted without triggering an error. See Launchpad bug 1801145.

menuScan and several record types documented with POD

The EPICS Wiki pages describing a number of standard record types has been converted into the Perl POD documentation format and added to the DBD files, so at build-time an HTML version of these documents is generated and installed into the htmls directory. Thanks to Tony Pietryla.

CA client tools learned -V option

This displays the version numbers of EPICS Base and the CA protocol.

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Changes made between 3.15.5 and 3.15.6

Unsetting environment variables

The new command epicsEnvUnset varname can be used to unset an environment variable.

Warning indicators in msi (and macLib) output

The libCom macro expansion library has been modified so that when the SUPPRESS_WARNINGS flag is set it will no longer include any ,undefined or ,recursive indicators in its output when undefined or recursive macros are encountered. These indicators were harmless when the output was fed into an IOC along with a definition for the macro, but when the msi tool was used to generate other kinds of files they caused problems. If the msi -V flag is used the markers will still be present in the output whenever the appropriate condition is seen.

Improvements to msi

In addition to fixing its response to discovering parsing errors in its substitution input file (reported as Launchpad bug 1503661) so it now deletes the incomplete output file, the msi program has been cleaned up a little bit internally.

All array records now post monitors on their array-length fields

The waveform record has been posting monitors on its NORD field since Base 3.15.0.1; we finally got around to doing the equivalent in all the other built-in record types, which even required modifying device support in some cases. This fixes Launchpad bug 1730727.

HOWTO: Converting Wiki Record Reference to POD

Some documentation has been added to the dbdToHtml.pl script explaining how Perl POD (Plain Old Documentation) markup can be added to .dbd files to generate HTML documentation for the record types. To see these instructions, run perl bin/<host>/dbdToHtml.pl -H or perldoc bin/<host>/dbdToHtml.pl.

Fix problem with numeric soft events

Changing from numeric to named soft events introduced an incompatibility when a numeric event 1-255 is converted from a DOUBLE, e.g. from a calc record. The post_event() API is not marked deprecated any more.

Also scanpel has been modified to accept a glob pattern for event name filtering and to show events with no connected records as well.

Add osiSockOptMcastLoop_t and osiSockTest

Added a new OS-independent typedef for multicast socket options, and a test file to check their correct operation.

Support for CONFIG_SITE.local in Base

This feature is mostly meant for use by developers; configuration settings that would normally appear in base/configure/CONFIG_SITE can now be put in a locally created base/configure/CONFIG_SITE.local file instead of having go modify or replace the original. A new .gitignore pattern tells git to ignore all configure/*.local files.

Fix broken EPICS_IOC_LOG_FILE_LIMIT=0 setting

The Application Developers' Guide says this is allowed and disables the limit on the log-file, but it hasn't actually worked for some time (if ever). Note that the iocLogServer will be removed from newer Base release sometime soon as its functionality can be implemented by other dedicated log servers such as logstash or syslog-ng.

Fixes lp:1786858 and part of lp:1786966.

Cleanup of startup directory

The files in the startup directory have not been maintained in recent years and have grown crufty (technical term). This release includes the following updates to these files:

• The Perl EpicsHostArch.pl script has been rewritten, and support for a few previously missing host architectures has been added to it.
• The EpicsHostArch.pl script has also been moved into the standard src/tools directory, from where it will be installed into lib/perl. In this new location it is no longer executable, so it must be run by the perl executable.
• The build system has been adjusted to look for EpicsHostArch.pl in both places if the EPICS_HOST_ARCH environment variable has not been set at build-time.
• Sites that used the original Perl script to set EPICS_HOST_ARCH as part of their standard environment will need to adjust their scripts when they upgrade to this release.
• The EpicsHostArch shell script has been replaced with a wrapper routine that calls the Perl EpicsHostArch.pl script. Sites that rely on this script to set EPICS_HOST_ARCH should consider switching to the Perl script instead.
• The Site.cshrc and Site.profile files have been renamed to unix.csh and unix.sh, respectively.
• The existing win32.bat file has been cleaned up and a new windows.bat file added for 64-bit targets. The contents of these files should be seen as examples, don't uncomment or install parts for software that you don't explicitly know that you need.

Recent Apple XCode Build Issues

The latest version of XCode will not compile calls to system() or clock_settime() for iOS targets. There were several places in Base where these were being compiled, although there were probably never called. The code has now been modified to permit iOS builds to complete again.

Prevent illegal alarm severities

A check has been added to recGblResetAlarms() that prevents records from getting an alarm severity higher than INVALID_ALARM. It is still possible for a field like HSV to get set to a value that is not a legal alarm severity, but the core IOC code should never copy such a value into a record's SEVR or ACKS fields. With this fix the record's alarm severity will be limited to INVALID_ALARM.

Fixes for Launchpad bugs

The following launchpad bugs have fixes included:

• lp: 1786320, dbCa subscribes twice to ENUM
• lp: 541221, assert (pca->pgetNative) failed in ../dbCa.c
• lp: 1747091, epicsTimeGetEvent() / generalTime bug
• lp: 1743076, Segfault in ca_attach_context() during exits
• lp: 1751380, Deadlock in ca_clear_subscription()
• lp: 1597809, Setting NAME field in DB file may break IOC
• lp: 1770292, get_alarm_double() inconsistent across record types
• lp: 1771298, Conversion of NaN to integer relies on undefined behavior

Updated VxWorks Timezone settings

Removed the settings for 2017; fixed the hour of the change for MET.

Fixed camonitor server side relative timestamps bug

Initialize the first time-stamp from the first monitor, not the client-side current time in this configuration.

Build changes for MSVC

Windows builds using Visual Studio 2015 and later now use the -FS compiler option to allow parallel builds to work properly.

We now give the -FC option to tell the compiler to print absolute paths for source files in diagnostic messages.

Extend maximum Posix epicsEventWaitWithTimeout() delay

The Posix implementation of epicsEventWaitWithTimeout() was limiting the timeout delay to at most 60 minutes (3600.0 seconds). This has been changed to 10 years; significantly longer maximum delays cause problems on systems where time_t is still a signed 32-bit integer so cannot represent absolute time-stamps after 2038-01-19. Our assumption is that such 32-bit systems will have been retired before the year 2028, but some additional tests have been added to the epicsTimeTest program to detect and fail if this assumption is violated.

New test-related make targets

This release adds several new make targets intended for use by developers and Continuous Integration systems which simplify the task of running the built-in self-test programs and viewing the results. Since these targets are intended for limited use they can have requirements for the build host which go beyond the standard minimum set needed to build and run Base.

test-results - Summarize test results

The new make target test-results will run the self-tests if necessary to generate a TAP file for each test, then summarizes the TAP output files in each test directory in turn, displaying the details of any failures. This step uses the program prove which comes with Perl, but also needs cat to be provided in the default search path so will not work on most Windows systems.

junitfiles - Convert test results to JUnit XML Format

The new make target junitfiles will run the self-tests if necessary and then convert the TAP output files into the more commonly-supported JUnit XML format. The program that performs this conversion needs the Perl module XML::Generator to have been installed.

clean-tests - Delete test result files

The new make target clean-tests removes any test result files from previous test runs. It cleans both TAP and JUnit XML files.

Fix DNS related crash on exit

The attempt to fix DNS related delays for short lived CLI programs (eg. caget) in lp:1527636 introduced a bug which cased these short lived clients to crash on exit. This bug should now be fixed.

Server bind issue on Windows

When a National Instruments network variables CA server is already running on a Windows system and an IOC or PCAS server is started, the IOC's attempt to bind a TCP socket to the CA server port number fails, but Windows returns a different error status value than the IOC is expecting in that circumstance (because the National Instruments code requests exclusive use of that port, unlike the EPICS code) so the IOC fails to start properly. The relevant EPICS bind() checks have now been updated so the IOC will request that a dynamic port number be allocated for this TCP socket instead when this happens.

Checking Periodic Scan Rates

Code has been added to the IOC startup to better protect it against bad periodic scan rates, including against locales where . is not accepted as a decimal separator character. If the scan period in a menuScan choice string cannot be parsed, the associated periodic scan thread will no longer be started by the IOC and a warning message will be displayed at iocInit time. The scanppl command will also flag the faulty menuScan value.

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Changes made between 3.15.4 and 3.15.5

dbStatic Library Speedup and Cleanup

Loading of database files has been optimized to avoid over-proportionally long loading times for large databases. As a part of this, the alphabetical ordering of records instances (within a record type) has been dropped. In the unexpected case that applications were relying on the alphabetic order, setting dbRecordsAbcSorted = 1 before loading the databases will retain the old behavior.

The routine dbRenameRecord() has been removed, as it was intended to be used by database configuration tools linked against a host side version of the dbStatic library that is not being built anymore.

Launchpad Bug-fixes

In addition to the more detailed change descriptions below, the following Launchpad bugs have also been fixed in this release:

• lp:1440186 Crash due to a too small buffer being provided in dbContextReadNotifyCache()
• lp:1479316 Some data races found using Helgrind
• lp:1495833 biRecord prompt groups are nonsensical
• lp:1606848 WSAIoctl SIO_GET_INTERFACE_LIST failed in Windows

Whole-Program Optimization for MS Visual Studio Targets

When using the Microsoft compilers a new build system variable is provided that controls whether whole program optimization is used or not. For static builds using Visual Studio 2010 this optimization must be disabled. This is controlled in the files configure/os/CONFIG_SITE.Common.windows-x64-static and configure/os/CONFIG_SITE.Common.win32-x86-static by setting the variable OPT_WHOLE_PROGRAM=NO to override the default value YES that would otherwise be used.

Note that enabling this optimization slows down the build process. It is not possible to selectively disable this optimization, when building a particular module say; Microsoft's linker will restart itself automatically with the -LTCG flag set and display a warning if it is asked to link any object files that were compiled with the -GL flag.

Add dynamic (variable length) array support to PCAS

Dynamic array sizing support was added to the IOC server (RSRV) in the Base-3.14.12 release, but has not until now been supported in the Portable Channel Access Server (PCAS). Channel Access server applications using the PCAS may not need to be modified at all; if they already push monitors with different gdd array lengths, those variable sizes will be forwarded to any CA clients who have requested variable length updates. The example CAS server application has been modified to demonstrate this feature.

In implementing the above, the gdd method gdd::put(const gdd *) now copies the full-sized array from the source gdd if the destination gdd is of type array, has no allocated memory and a boundary size of 0.

Additional epicsTime conversion

The EPICS timestamp library (epicsTime) inside libCom's OSI layer has been extended by routines that convert from struct tm to the EPICS internal epicsTime type, assuming UTC - i.e. without going through the timezone mechanism. This solves issues with converting from the structured type to the EPICS timestamp at driver level from multiple threads at a high repetition rate, where the timezone mechanism was blocking on file access.

MinGW Cross-builds from Linux

The build configuration files that allow cross-building of the 32-bit win32-x86-mingw cross-target have been adjusted to default to building shared libraries (DLLs) as this is now supported by recent MinGW compilers. The 64-bit windows-x64-mingw cross-target was already being built that way by default. The configuration options to tell the minGW cross-compiler to link programs with static versions of the compiler support libraries have now been moved into the CONFIG_SITE.linux-x86.<target> files.

General Time updates

The iocInit code now performs a sanity check of the current time returned by the generalTime subsystem and will print a warning if the wall-clock time returned has not been initialized yet. This is just a warning message; when a time provider does synchronize the IOC will subsequently pick up and use the correct time. This check code also primes the registered event system provider if there is one so the epicsTimeGetEventInt() routine will work on IOCs that ask for event time within an interrupt service routine.

The osiClockTime provider's synchronization thread (which is only used on some embedded targets) will now poll the other time providers at 1Hz until the first time it manages to get a successful timestamp, after which it will poll for updates every 60 seconds as before.

The routine generalTimeGetExceptPriority() was designed for use by backup (lower priority) time providers like the osiClockTime provider which do not have their own absolute time reference and rely on other providers for an absolute time source. This routine no longer implements the ratchet mechanism that prevented the time it returned from going backwards. If the backup clock's tick-timer runs fast the synchronization of the backup time provider would never allow it to be corrected backwards when the ratchet was in place. The regular epicsTimeGetCurrent() API still uses the ratchet mechanism, so this change will not cause the IOC to see time going backwards.

Microsoft Visual Studio builds

The build configuration files for builds using the Microsoft compilers have been updated, although there should be no noticeable difference at most sites. One extra compiler warning is now being suppressed for C++ code, C4344: behavior change: use of explicit template arguments results in ... which is gratuitous and was appearing frequently in builds of the EPICS V4 modules.

Cross-builds of the windows-x64 target from a win32-x86 host have been removed as they don't actually work within the context of a single make run. Significant changes to the build configuration files would be necessary for these kinds of cross-builds to work properly, which could be done if someone needs them (email Andrew Johnson before working on this, and see this stack-overflow answer for a starting point).

Bazaar keywords such as 'Revision-Id' removed

In preparation for moving to git in place of the Bazaar revision control system we have removed all the keywords from the Base source code.

Linux systemd service file for CA Repeater

Building this version of Base on a Linux system creates a systemd service file suitable for starting the Channel Access Repeater under systemd. The file will be installed into the target bin directory, from where it can be copied into the appropriate systemd location and modified as necessary. Installation instructions are included as comments in the file.

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Changes made between 3.15.3 and 3.15.4

New string input device support "getenv"

A new "getenv" device support for both the stringin and lsi (long string input) record types can be used to read the value of an environment variable from the IOC at runtime. See base/db/softIocExit.db for sample usage.

Build rules and DELAY_INSTALL_LIBS

A new order-only prerequisite build rule has been added to ensure that library files (and DLL stubs on Windows) get installed before linking any executables, which resolves parallel build problems on high-powered CPUs. There are some (rare) cases though where a Makefile has to build an executable and run it to be able to compile code for a library built by the same Makefile. With this new build rule GNUmake will complain about a circular dependency and the build will probably fail in those cases. To avoid this problem the failing Makefile should set DELAY_INSTALL_LIBS = YES before including the $(TOP)/configure/RULES file, disabling the new build rule.

IOC environment variables and build parameters

The IOC now sets a number of environment variables at startup that provide the version of EPICS Base it was built against (EPICS_VERSION_...) and its build architecture (ARCH). In some cases this allows a single iocBoot/ioc directory to be used to run the same IOC on several different architectures without any changes.

There are also 3 new environment parameters (EPICS_BUILD_...) available that C/C++ code can use to find out the target architecture, OS class and compiler class it was built with. These may be useful when writing interfaces to other languages.

New implementation of promptgroup/gui_group field property

The mechanism behind the promptgroup() field property inside a record type definition has been changed. Instead of using a fixed set of choices, the static database access library now collects the used gui group names while parsing DBD information. Group names should start with a two-digit number plus space-dash-space to allow proper sorting of groups.

The include file guigroup.h that defined the fixed set of choices has been deprecated. Instead, use the conversion functions between index number and group string that have been added to dbStaticLib.

When a DBD file containing record-type descriptions is expanded, any old-style GUI_xxx group names will be replaced by a new-style string for use by the IOC. This permits an older record type to be used with the 3.15.4 release, although eventually record types should be converted by hand with better group names used.

CA server configuration changes

RSRV now honors EPICS_CAS_INTF_ADDR_LIST and binds only to the provided list of network interfaces. Name searches (UDP and TCP) on other network interfaces are ignored. For example on a computer with interfaces 10.5.1.1/24, 10.5.2.1/24, and 10.5.3.1/24, setting EPICS_CAS_INTF_ADDR_LIST='10.5.1.1 10.5.2.1' will accept traffic on the .1.1 and .2.1, but ignore from .3.1

RSRV now honors EPICS_CAS_IGNORE_ADDR_LIST and ignores UDP messages received from addresses in this list.

Previously, CA servers (RSRV and PCAS) would build the beacon address list using EPICS_CA_ADDR_LIST if EPICS_CAS_BEACON_ADDR_LIST was no set. This is no longer done. Sites depending on this should set both environment variables to the same value.

IPv4 multicast for name search and beacons

libca, RSRV, and PCAS may now use IPv4 multicasting for UDP traffic (name search and beacons). This is disabled by default. To enable multicast address(s) must be listed in EPICS_CA_ADDR_LIST for clients and EPICS_CAS_INTF_ADDR_LIST for servers (IOCs should set both). For example:

EPICS_CAS_INTF_ADDR_LIST='224.0.2.9' EPICS_CA_ADDR_LIST=224.0.2.9

Please note that no IPv4 multicast address is officially assigned for Channel Access by IANA. The example 224.0.2.9 is taken from the AD-HOC Block I range.

Moved mlockall() into its own epicsThread routine

Since EPICS Base 3.15.0.2 on Posix OSs the initialization of the epicsThread subsystem has called mlockall() when the OS supports it and thread priority scheduling is enabled. Doing so has caused problems in third-party applications that call the CA client library, so the functionality has been moved to a separate routine epicsThreadRealtimeLock() which will be called by the IOC at iocInit (unless disabled by setting the global variable dbThreadRealtimeLock to zero).

Added dbQuietMacroWarnings control

When loading database files, macros get expanded even on comment lines. If a comment contains an undefined macro, the load still continues but an error message gets printed. For this release the error message has been changed to a warning, but even this warning can be made less verbose by setting this new variable to a non-zero value before loading the file, like this:

    var dbQuietMacroWarnings 1      iocsh
    dbQuietMacroWarnings=1          VxWorks

This was Launchpad bug 541119.

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Changes from the 3.14 branch between 3.15.3 and 3.15.4

NTP Time Provider adjusts to OS tick rate changes

Dirk Zimoch provided code that allows the NTP Time provider (used on VxWorks and RTEMS only) to adapt to changes in the OS clock tick rate after the provider has been initialized. Note that changing the tick rate after iocInit() is not advisable, and that other software might still misbehave if initialized before an OS tick rate change. This change was back-ported from the 3.15 branch.

Making IOC ca_get operations atomic

When a CA client gets data from an IOC record using a compound data type such as DBR_TIME_DOUBLE the value field is fetched from the database in a separate call than the other metadata, without keeping the record locked. This allows some other thread such as a periodic scan thread a chance to interrupt the get operation and process the record in between. CA monitors have always been atomic as long as the value data isn't a string or an array, but this race condition in the CA get path has now been fixed so the record will stay locked between the two fetch operations.

This fixes Launchpad bug 1581212, thanks to Till Strauman and Dehong Zhang.

New CONFIG_SITE variable for running self-tests

The 'make runtests' and 'make tapfiles' build targets normally only run the self-tests for the main EPICS_HOST_ARCH architecture. If the host is able to execute self-test programs for other target architectures that are being built by the host, such as when building a -debug version of the host architecture for example, the names of those other architectures can be added to the new CROSS_COMPILER_RUNTEST_ARCHS variable in either the configure/CONFIG_SITE file or in an appropriate configure/os/CONFIG_SITE.<host>.Common file to have the test programs for those targets be run as well.

Additional RELEASE file checks

An additional check has been added at build-time for the contents of the configure/RELEASE file(s), which will mostly only affect users of the Debian EPICS packages published by NSLS-2. Support modules may share an install path, but all such modules must be listed adjacent to each other in any RELEASE files that point to them. For example the following will fail the new checks:

    AUTOSAVE = /usr/lib/epics
    ASYN = /home/mdavidsaver/asyn
    EPICS_BASE = /usr/lib/epics

giving the compile-time error

    This application's RELEASE file(s) define
        EPICS_BASE = /usr/lib/epics
    after but not adjacent to
        AUTOSAVE = /usr/lib/epics
    Module definitions that share paths must be grouped together.
    Either remove a definition, or move it to a line immediately
    above or below the other(s).
    Any non-module definitions belong in configure/CONFIG_SITE.

In many cases such as the one above the order of the AUTOSAVE and ASYN lines can be swapped to let the checks pass, but if the AUTOSAVE module depended on ASYN and hence had to appear before it in the list this error indicates that AUTOSAVE should also be built in its own private area; a shared copy would likely be incompatible with the version of ASYN built in the home directory.

String field buffer overflows

Two buffer overflow bugs that can crash the IOC have been fixed, caused by initializing a string field with a value larger than the field size (Launchpad bug 1563191).

Fixed stack corruption bug in epicsThread C++ API

The C++ interface to the epicsThread API could corrupt the stack on thread exit in some rare circumstances, usually at program exit. This bug has been fixed (Launchpad bug 1558206).

RTEMS NTP Support Issue

On RTEMS the NTP Time Provider could in some circumstances get out of sync with the server because the osdNTPGet() code wasn't clearing its input socket before sending out a new request. This (Launchpad bug 1549908) has now been fixed.

CALC engine bitwise operator fixes

The bitwise operators in the CALC engine have been modified to work properly with values that have bit 31 (0x80000000) set. This modification involved back-porting some earlier changes from the 3.15 branch, and fixes Launchpad bug 1514520.

Fix ipAddrToAsciiAsync(): Don't try to join the daemon thread

On process exit, don't try to stop the worker thread that makes DNS lookups asynchronous. Previously this would wait for any lookups still in progress, delaying the exit unnecessarily. This was most obvious with catools (eg. cainfo). lp:1527636

Fix epicsTime_localtime() on Windows

Simpler versions of the epicsTime_gmtime() and epicsTime_localtime() routines have been included in the Windows implementations, and a new test program added. The original versions do not report DST status properly. Fixes Launchpad bug 1528284.