These release notes describe changes that have been made since the previous release of this series of EPICS Base. Note that changes which were merged up from commits to the 3.15 branch are described further down this file under the 3.15 release to which they were originally committed. Thus it is important to read more than just the first section to understand everything that has changed in each release.
The PVA submodules each have their own individual sets of release notes which should also be read to understand what has changed since earlier releases.
Thanks to several attendees at the 2022 EPICS Codeathon the number of header files with Doxygen annotations in the EPICS Core has again increased.
The top-level make targets uninstall
,
archuninstall
and similar no longer trigger the
clean
target which empties build directories, this was a
bug introduced in 7.0.5.
The make distclean
target now properly deletes the
generated file(s) modules/RELEASE.<host>.local
which
are essential to build the external submodules under the
modules
directory, and should not crash if the build is
configured with INSTALL_LOCATION
pointing to an empty
external directory (i.e. if you run make distclean
twice in
succession). When INSTALL_LOCATION
is set in the files
configure/CONFIG_SITE
or
configure/CONFIG_SITE.local
the
modules/RELEASE.<host>.local
file will now be
regenerated in case the install path has been modified.
Note that passing INSTALL_LOCATION=<path>
on the
make command-line will only work if you have run
make distclean
immediately beforehand, as the
modules/RELEASE.<host>.local
file must be recreated
using the new path.
capr.pl
The capr.pl
script can now display records from older
Base versions to which fields have since been added, and shows long
strings and array data up to 10 elements, use the new -n
option to increase that number. The script is fully event-driven and
prints all the field data received by the end of the CA wait time
(-w
option which defaults to 2 seconds). The interest level
can now be specified using the -l
option before the PV
name, and the new -D
flag outputs debugging
information.
VxWorks 6.9 can do its own OS clock time synchronization, if it has
been configured by setting SNTPC_PRIMARY_IPV4_ADDR
. Since
EPICS 3.15.3 the IOC time support code has checked for the existence of
the VxWorks time synchronization task and avoided starting the EPICS one
if the OS task exists and the OS clock gives a "recent" time (i.e. after
when EPICS was compiled), unless the environment variable
EPICS_TS_FORCE_NTPTIME
is also set. However a logic error
in that code required the environment variable to be set in more cases
than it should have.
This error has been fixed and the IOC should work normally if the
VxWorks task is configured and running. The TIMEZONE
value
for the year is also now calculated at initialization in this
configuration, previously it was only done when the IOC synchronzation
task was used. Setting the above environment variable will now cause the
IOC support code to shut down the VxWorks synchronization thread (if
running) before starting the EPICS one.
Running the iocsh command ClockTime_Report
now shows
whether the VxWorks task is running as well as giving the state of the
IOC synchronization task. The ClockTime_Init
command can
also be used to stop or restart the IOC time synchronization task while
the IOC is running, depending on the 0
or 1
parameter passed to it. This last change also applies to RTEMS IOCs.
struct db_field_log
This change may cause channel filters which manipulate array updates to fail to compile.
To avoid potential speculation issues arising from overlapping code
pointers with data values, union dbfl_ref
is modified to
remove the dtor
member. dtor
is moved out into
the enclosing struct db_field_log
.
So eg. using a db_field_log* p
, the expression
p->u.r.dtor
must be changed to
(p)->dtor
.
The order over operations when processing a waveformRecord is adjusted so that updates to NORD is posted with the correct timestamp.
When built with a compiler supporting
__has_include<>
, the presence of the
<readline/readline.h>
will be used to automatically
determine a default value for COMMANDLINE_LIBRARY
.
Mingw builds with readline support now link -ltermcap
instead of -lcurses
.
This should not effect sites which set explicitly set
COMMANDLINE_LIBRARY
as the only definition in Base now has
the form COMMANDLINE_LIBRARY ?= ...
.
The Perl CA bindings have been fixed to handle zero-length long string data properly.
aao
gains OMSL
and DOL
The aao
record types gains the same DOL
functionality found in other output record types (ao
,
longout
, etc.)
RSRV_SERVER_PORT
During iocInit()
, the environment variable
RSRV_SERVER_PORT
is set with the TCP port number
selected.
dbdExpand.pl
sorts all items by nameDBD files generated by the dbdExpand.pl
script are now
sorted within each item type by the primary name of the item. The result
should resolve any issues with reproducable builds. No option is
provided to prevent the sorting, previously the order was essentially
random and varied each time.
dbExpand.pl
sorts
records by nameRecords are now output by this program in order, sorted by name. The
new flag -s
can be given to output the records in the same
order they were read in, instead of sorting them.
Note that there are currently no build rules provided with Base which make use of this program.
SIMM=RAW support has been added for the relevant output record types (ao, bo, mbbo, mbboDirect). RAW simulation mode will have those records do the appropriate conversion and write RVAL to the location pointed to by SIOL.
On some targets, if a thread not created by
epicsThreadCreate*()
directly or indirectly calls an
epicsThread*()
function, a specific tracking struct is
allocated.
Prior to this release, on POSIX and WIN32 targets, this struct would
not be free()
d, resulting in a memory leak.
This release fixed the leak on POSIX targets.
See the associated github issue 241 for WIN32 status.
CHECK_RELEASE = WARN
This now works again, it was broken in 2019 (7.0.3.1) by an errant commit.
DISP
as design-time fieldThe DISP field can be set to a non-zero value to prevent records being changed from outside the IOC (this is ancient behavior), but has never been documented as being usable at design-time (DCT=Yes in the Record Reference tables). This has now been changed.
epicsInt8
signed on all architecturesThe epicsInt8
and thus DBF_CHAR
types have
always been unsigned on architectures where char
is
unsigned, for example on many PowerPC CPU architectures. This was
counter-intuitive, and resulted in IOC behavior differing between
architectures when converting DBF_CHAR
values into a signed
integer or floating point type.
WARNING: This fix may change behavior of existing
databases on target architectures with unsigned char
(mainly PowerPC) when using input links to read from CHAR
arrays. Architectures with signed char
(usually x86) should
be unaffected, although some compilers might generate new warnings.
Several types of hardware links (VME_IO
,
CAMAC_IO
, etc) now accept hexadecimal and octal numbers.
(Hexadecimal numbers had already been valid up to EPICS R3.15.) This
change may introduce incompatibilities when using numbers with leading
0
as they will now be parsed as octal.
epicsEvent
Heinz Junkes provided a new implementation of the
epicsEvent
API suitable for RTEMS Posix targets (RTEMS 5.1
and later). In review a few issues related to overflow of timeout values
surfaced in this and other embedded implementations, and these were also
been fixed in this Pull Request. The API documentation for this and some
other routines has also been updated.
The names of breakpoint tables were made unnecessarily strict when
DBD file processing was moved to Perl for the 3.15 release series. Table
names may now contain the special characters _
-
:
;
.
[
]
<
>
in
addition to letters and digits.
undefined
in configure/RELEASE filesPrevents Use of uninitialized value
warnings from
convertRelease.pl.
Many internal error messages now emit ANSI escape sequences to highlight the words "ERROR" and "WARNING" in an attempt to make occurrences more noticeable during IOC startup.
The macros ERL_ERROR
and ERL_WARNING
are
defined for external usage, and expand as string constants. eg.
#include <errlog.h>
#ifndef ERL_ERROR
# define ERL_ERROR "ERROR"
#endif
void fn() {
...
(ERL_ERROR ": something bad happens :(\n"); errlogPrintf
ANSI escapes are automatically removed from errlog output not
destined for a terminal. For example, for logClient, if stderr is
redirected, or if unsupported ($TERM
not set, or Windows
< 10).
dbnd
filter pass through DBE_ALARM|DBE_PROPERTY
The dbnd
server side filter now passes through alarm and
property change events, even when not exceeding the deadband.
mbboDirectRecord
enhancementsThe bit fields B0
- B1F
of this record are
now always updated and have a monitor posted when the VAL
field is set and the record processed. It is now possible to initialize
the record's value by setting the bit fields inside a database file as
long as no other method was used to initialize it (suc as setting
VAL
directly, using DOL
, or by an initial
readback from device support). A new internal field OBIT
was added to store information about monitors posted on the bit
fields.
Some scripts now make use of features that were introduced to this Perl version that was released in 2009.
DBF_MENU
fields fixedGH:183 These were broken in a previous release, but now work again.
GH:194 This was broken in a previous release, but now works again.
-DDEBUG
compiler flag no longer breaks the
build.GH:192 Both GCC and CLANG compiler intrisics used for the epicsAtomic APIs have been revised; implementations using CLANG should now run faster as they now use the compiler's built-in atomic functions instead of taking a mutex.
GH:185 This
was done to simplify the code and may have improved performance slightly
for some uses. Support for the old NTP-specific struct l_fp
has been dropped but all other routines and methods of the
class epicsTime
function as before.
Many of the built-in record types have had improvements to their documentation with additional fields added to the tables, rewrites of descriptions and links to other documents added or fixed.
These target architectures have been removed:
The new major release of the RTEMS real-time OS contains many changes including the ability to support SMP systems. This release of EPICS can still be built with RTEMS 4.9.x or 4.10.x and should work just the same as earlier releases, although due to code having moved around we recommend thorough testing before this release is first used in production systems.
This release of EPICS comes with support for several new RTEMS targets running on RTEMS 5:
The EPICS support for RTEMS 4 has always relied on RTEMS-specific
kernel APIs which cannot be used on an SMP system, so a new port was
created to use the Posix real-time APIs that are now recommended for
RTEMS 5. Note that a single installation of EPICS cannot build both
RTEMS 4 and RTEMS 5 targets, if you need to support targets running on
both versions you must use a separate installation, and be sure to run
make distclean
if switching a single source tree from one
to the other (both header files and dependency files are different
between the two and must be cleaned out).
The configuration variable RTEMS_VERSION in the EPICS config file
configure/os/CONFIG_SITE.Common.RTEMS
must be set to the
full 3- part version number for RTEMS 4 releases, e.g.
4.9.1
, 4.10.2
but for RTEMS 5.1 and later it
must only contain the major version number e.g. 5
.
Some RTEMS BSPs can be built and may work with the newer libbsd network stack which RTEMS is moving over to, but most of the MVME boards (and the uC5282) still require the legacy network stack.
The dependency on bspExt has been removed, EPICS now provides its own routine for VMEbus probing (or uses one built into the BSP).
Anyone using this release on RTEMS is advised to discuss problems building or running it on either the tech-talk or core-talk email lists so the core developers can help with and find out about any problems with the old or new port.
Known Issues:
epicsEnvShow
accepts a glob patternThe optional argument to epicsEnvShow can now be a glob pattern.
epicsStrnGlobMatch()
The function
epicsStrnGlobMatch(char* str, size_t len, char* pattern)
works exactly the same as epicsStrGlobMatch()
but takes an
additional length arguments which limits the number of characters of
str
to match.
A process using libca which does not find an existing caRepeater
process will attempt to start one by running the caRepeater executable.
This is not always possible, usually when caRepeater is not in
$PATH
. Now, instead of printing a warning, an internal
caRepeater thread will be started (as is done be RTEMS and vxWorks
targets).
If this fallback occurs, the lifetime of the caRepeater thread may be shorter than the lifetime of a separate caRepeater process would have been.
It remains the recommended practice to explicitly start a caRepeater
instance. Examples of both systemd (caRepeater.service
) and
sysv (S99caRepeater
) scripts may be found under
bin/
.
var
commandWhen used with one argument, the var
command can be used
with a glob pattern for printing matching variables.
FINAL_LOCATION
The FINAL_LOCATION
make variable has for some time been
an undocumented means of performing a staged build. This is a build
which "installs" to a temporary location, which will later be moved to a
final location.
This has now been added to configure/CONFIG_SITE
.
Usage analogous to the autotools recipe
./configure --prefix=/usr/lib/epics
make install DESTDIR=/tmp/build
would be
make INSTALL_LOCATION=/tmp/build FINAL_LOCATION=/usr/lib/epics
FINAL_LOCATION
is now correctly used in systemd and sysv
init scripts caRepeater.service
,
S99caRepeater
, and S99logServer
.
${PWD}
IOC shell will now ensure ${PWD}
is set on startup, and
updated by the cd
iocsh function.
Two new fields have been added to dbCommon
so will be
present in all records: AMSG
and UTAG
.
AMSG
AMSG
can hold an arbitrary 40-character string,
providing additional information about the alarm condition indicated in
STAT
and SEVR
. With no alarm it will hold an
empty string. The new recGblSetSevrMsg()
function can be
used in place of recGblSetSevr()
to signal an alarm while
providing a message.
For example, a device support's read_bi()
routine for a
hypothetical multi-channel ethernet attached device might flag a
communication error between the IOC and controller, or an error
involving a certain channel like this:
static long read_bi(biRecord* prec) {
...
if (!priv->connected) {
(prec, COMM_ALARM, INVALID_ALARM,
recGblSetSevrMsg"No controller connected");
return S_dev_noDevice;
}
if (!priv->err) {
(prec, READ_ALARM, INVALID_ALARM,
recGblSetSevrMsg"Channel %u disconnexted", priv->chan);
return S_dev_noDevice;
}
return status;
}
UTAG
UTAG
holds an epicsUInt64
value which is
semantically part of the record's timestamp (TIME
). The
value defaults to zero if not explicitly set. Device support or an event
time provider which supports this feature may write a tag value directly
to the dbCommon::utag
field.
TSEL
links will copy both TIME
and
UTAG
between records if the link type supports this (CA
links do not).
A utag
server side channel filter has been added which
can be configured to filter out monitor updates which don't pass the
test (UTAG & M) == V
where M
and
V
are client specified integers. For example running the
command camonitor BPM0:X.{utag:{M:1,V:1}}
will only show
updates for which (UTAG & 1) == 1
i.e. the least
significant bit of the UTAG
field is set.
This feature is intended for use by intelligent devices which can provide contextual information along with a value/alarm/time. For example, a beam diagnostic device which is aware of whether a beam signal should be present (eg. from a global timing system).
Two new optional methods have been added to the Link Support Entry
Table (struct lset
): lset::getAlarmMsg()
and
lset::getTimeStampTag()
. See comments in dbLink.h for
details on implementing these.
Two new accessor functions have also been added which call these
methods: dbGetAlarmMsg()
and
dbGetTimeStampTag()
.
User code wishing to call these interfaces while maintaining compatibility with older versions of Base may add some of the following macro definitions, and ensure that the variables referenced by output pointers are initialized.
#ifndef HAS_ALARM_MESSAGE
# define recGblSetSevrMsg(REC, STAT, SEVR, ...) recGblSetSevr(REC, STAT, SEVR)
#endif
#ifndef dbGetAlarmMsg
# define dbGetAlarmMsg(LINK, STAT, SEVR, BUF, BUFLEN) dbGetAlarm(LINK, STAT, SEVR)
#endif
#ifndef dbGetTimeStampTag
# define dbGetTimeStampTag(LINK, STAMP, TAG) dbGetTimeStamp(LINK, STAMP)
#endif
The unit test programs that are run by the make runtests
or make tapfiles
commands get executed by a .t
wrapper script which is normally generated by the EPICS
makeTestfile.pl
program. Those generated wrapper scripts
now impose a time-limit on the test program they execute, and will kill
it if it runs for longer than 500 seconds (8 minutes 20) without
exiting. That time-limit can be changed for any such test by modifying
the Makefile which creates and runs the .t
wrapper
script.
Setting the environment variable EPICS_UNITTEST_TIMEOUT
to the desired number of seconds while the Makefile is generating the
test script changes the timeout in that script. For example:
TESTSCRIPTS_HOST += hourLongTest.t
hourLongTest.t: export EPICS_UNITTEST_TIMEOUT=3600
When selecting such a timeout remember that different Continuous Integration systems such as GitHub Actions and Appveyor run on processors with different speeds, so allow enough head-room for slower systems to complete the test.
Test programs written directly in Perl as a .plt
script
should implement a similar timeout for themselves. The "netget" test in
Base does this in a way that works on Windows as well as Unix-like
hosts.
Krisztian Loki reported segfaults occurring when a Soft Channel aai record INP field was a DB link to an array field of a compress record. This was caused by the aai record's pass-0 device support initialization clashing with the semantics of the new link support API.
The aai record has been modified to allow the Soft Channel device support to request a pass-1 initialization callback. See the Device Support section of the Array Analogue Input Record Reference pages in this release for the API changes, which are fully backwards compatible for existing aai device support.
Kay
Kasemir reported that it is possible to change the Base record
type's default DTYP if a device()
entry is seen before the
recordtype()
definition to which it refers. The default
DTYP is the first device loaded, which is normally the
Soft Channel
support from Base. A warning was being
displayed by dbdExpand when a device()
entry was see first,
but that was easily missed.
The DBD file parser in dbdExpand.pl has now been modified to make
this an error, although the registerRecordDeviceDriver.pl script will
still accept device()
entries without having their
recordtype()
loaded since this is necessary to compile
device supports as loadable modules.
On Posix systems, epicsMutex now support priority inheritance if
available. The IOC needs to run with SCHED_FIFO engaged to use these.
Support for Posix implementations before POSIX.1-2001
(_XOPEN_SOURCE < 500
, glibc version < 2.3.3) has been
dropped.
The IOC shell's epicsMutexShowAll
command prints "PI is
enabled" if both libc and kernel support is present.
Since 7.0.3.1 a Windows IOC could not run for more than 49.7 days; at that time the periodic scan threads would stop processing. This issue should now have been fixed and the Monotonic time functions on Windows should return values which count at nanosecond resolution. However we have not waited 49.7 days to test the final software, so there is a small chance that it's still broken.
This fixes lauchpad bug #1896295.
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
.
It should also be possible to build universal binaries containing
code for both the Intel and arm64 processors under either target name:
In the appropriate configure/os/CONFIG_SITE.Common.darwin-*
file add the other architecture class name to the
ARCH_CLASS
variable (after a space).
epicsStrSimilarity()
The new epicsStrSimilarity()
routine in epicsString.h
uses a modified Levenshtein distance to compare two strings, with a
character case difference being half the weight of a full substitution.
The double return value falls in the range 0.0 (identical) through 1.0
(no characters matching), or -1.0 for error. This is used to provide a
new "Did you mean ..." suggestion when a .db file provides an invalid
choice string for a DBF_MENU
or DBF_DEVICE
field.
VALID_BUILDS
type "Command"Target architectures that support command-line programs that run the
main()
routine can now be marked as such in their
VALID_BUILDS
definition. This enables a new set of Makefile
target variables PROD_CMD
(similar to
PROD_HOST
), LIBRARY_CMD
(like
LIBRARY_HOST
, etc.), LOADABLE_LIBRARY_CMD
,
OBJS_CMD
, SCRIPTS_CMD
,
TARGETS_CMD
, TESTLIBRARY_CMD
,
TESTSCRIPTS_CMD
and TESTPROD_CMD
. The CA
client tools and programs such as caRepeater
are now built
for all such targets (previously they were built for all targets except
where the OS was VxWorks, RTEMS and iOS).
If you have created your own site-specific target architectures you
may need to update the VALID_BUILDS
variable if it gets set
in your locally added
configure/os/CONFIG.Common.<arch>
files. This is
usually only needed for cross-compiled targets though since
CONFIG.Common.UnixCommon
sets it.
The other VALID_BUILDS
types are "Host" for target
architectures that can compile and run their own programs
(PROD_HOST
etc.), and "Ioc" for targets that can run IOCs
(PROD_IOC
etc.).
The YAJL parser and generator routines in libcom and in the IOC's dbStatic parser now support the JSON5 standard. This adds various features to JSON without altering the API for the code other than adding a new option to the YAJL parser which can be used to disable JSON5 support if desired. The new features include:
Infinity
,
-Infinity
and NaN
.'
, inside which the double-quote character "
doesn't have to be escaped with a back-slash \
, although a
single-quote character '
(or apostrophy) must be escaped
inside a single-quoted string.+
.0x
or 0X
..
(after the sign or before the exponent respectively if
present).[A-Za-z_][A-Za-z_0-9]*
don't have to be enclosed in quotes at all. The dbStatic parser adds
.+-
to the characters allowed but will add quotes around
such keys before passing them to YAJL.Code that must also compile against the older API can use the new C
macro HAS_JSON5
to detect the new version. This macro is
defined on including either the yajl_parse.h
or
yajl_gen.h
headers, which also provide the new
configuration options to turn on JSON5 support.
All APIs in the IOC that previously accepted JSON will now accept JSON5. This includes JSON field modifiers (channel filters), JSON link addresses, constant input link array values and database info-tag values. JSON values that get parsed by the dbLoadRecords() routine are still more liberal than the other uses as the ability to use unquoted strings that was called "relaxed JSON" is still supported, whereas the JSON5 standard and the YAJL parser only allow unquoted strings to be used for keys in a JSON map.
This also fixes lauchpad bug #1714455.
epicsStrnRawFromEscaped()
and
dbTranslateEscape()
declared in epicsString.h no longer
accept octal escaped characters such as \123
or
\41
.epicsStrnEscapedFromRaw()
now generates hex
excaped characters for unprintable characters such as
\x1f
.\xXX
must now contain
exactly 2 hex digits.\0
now generates a zero byte in the
raw string, but the other digits 1-9
should not appear
after a back-slash.These changes are to more closely follow the JSON5 standard, which
doesn't support octal character escapes or the \a
(Bel,
\x07
) escape sequence.
Input database links can now use channel filters, it is not necessary to make them CA links for the filters to work.
The Soft Channel device support for ai records now returns failure when fetching the INP link fails.
Several modifications have been made to properly support zero-length array values inside the IOC and over Channel Access. Some of these changes may affect external code that interfaces with the IOC, either directly or over the CA client API so we recommend thorough testing of any external code that handles array fields when upgrading to this release.
Since these changes affect the Channel Access client-side API they
will require rebuilding any CA Gateways against this version or Base to
properly handle zero-length arrays. The caget
,
caput
and camonitor
client programs are known
to work with empty arrays as long as they were built with this or a
later version of EPICS.
dbr_size_n(TYPE, COUNT)
macroWhen called with COUNT=0 this macro no longer returns the number of bytes required for a scalar (1 element) but for an empty array (0 elements). Make sure code that uses this doesn't call it with COUNT=0 when it really means COUNT=1.
Note that the db_access.h header file is included by cadef.h so the change can impact Channel Access client programs that use this macro.
The ca_array_put()
and
ca_array_put_callback()
routines now accept an element
count of zero, and will write a zero-length array to the PV if possible.
No error will be raised if the target is a scalar field though, and the
field's value will not be changed.
The ca_array_get_callback()
and
ca_create_subscription()
routines still accept a count of
zero to mean fetch as many elements as the PV currently holds.
Client programs should be prepared for the count
fields
of any struct event_handler_args
or
struct exception_handler_args
passed to their callback
routines to be zero.
The soft device support for the array records aai, waveform, and subArray as well as the aSub record type now correctly report reading 0 elements when getting an empty array from an input link.
The dbpf command now accepts array values, including empty arrays, when provided as a JSON string. This must be enclosed in quotes so the iocsh argument parser sees the JSON as a single argument:
epics> dbpf wf10:i32 '[1, 2, 3, 4, 5]'
DBF_LONG[5]: 1 = 0x1 2 = 0x2 3 = 0x3 4 = 0x4 5 = 0x5
Record links that get a scalar value from an array that is currently
empty will cause the record that has the link field to be set to an
INVALID/LINK
alarm status. The record code must call
dbGetLink()
with pnRequest=NULL
for it to be
recognized as a request for a scalar value though.
This changes the semantics of passing pnRequest=NULL
to
dbGetLink()
, which now behaves differently than passing it
a pointer to a long integer containing the value 1, which was previously
equivalent. The latter can successfully fetch a zero-element array
without triggering a LINK alarm.
Record links that put a zero-element array into a scalar field will
now set the target record to INVALID/LINK
alarm without
changing the field's value. Previously the field was set to 0 in this
case (with no alarm). The target field must be marked as
special(SPC_DBADDR)
to be recognized as an array field, and
its record support must define a put_array_info()
routine.
The record processing code for records with output links has been modified to update the timestamp via recGblGetTimeStamp() before processing the output links. This ensures that other records which get processed via an output link can use TSEL links to fetch the timestamp corresponding to the data processed by the output link.
This change could result in a slightly earlier timestamp for records whose output link is handled by a device driver, but only if the device driver does not handle its own timestamping via TSE -2 and instead uses TSE 0 or TSE -1 to get current time or best time, and the time spent in the device driver is greater than your timestamp provider resolution. For these situations it is recommended to set TSE to -2 and set the timestamp in the driver code.
A new iocsh command registerAllRecordDeviceDrivers
is
provided and also defined as a function in iocshRegisterCommon.h. This
uses dynamic symbol lookup with epicsFindSymbol()
to
perform the same function as a generated
*_registerRecordDeviceDriver()
function. This allows for an
alternative approach to dynamic loading of support modules without code
generation.
This feature is not intended for use by IOCs constructed using the standard EPICS application build process and booted from a startup script in an iocBoot subdirectory, although it might work in some of those cases — the generated registerRecordDeviceDriver.cpp file is normally required to link everything referred to in the DBD file into the IOC's executable. It also won't work with some static build configurations, or if the symbol table has been stripped from the executable.
{const:"string"}
to initialize an array of
DBF_CHAR
It is now possible to use a JSON Const link with a string value to
initialize an aai or waveform record that has FTVL
set to
CHAR
through the INP link. The string length is not limited
to 40 characters. This should also work for aSub record inputs similarly
configured as long strings.
record(waveform, "wf") {
field(NELM, 100)
field(FTVL, CHAR)
field(INP, {const:"This is a waveform and more than 40 characters"})
}
undefine
GNUmake added the directive undefine
in version 3.82 to
allow variables to be undefined. Support for this has been added to the
EPICS Release file parser, so undefine
can now be used in
configure/RELEASE files to unset variables.
Build configuration files for a new cross-build architecture
linux-aarch64
have been added, and the targets
linux-arm_el
and linux-arm_eb
removed. The
64-bit ARM architecture target doesn't have build files for self-hosting
yet but they should be relatively easy to add, contributions
welcome!
The following bugs/issues have fixes included in this release:
TCP_NODELAY
declaration.Builds of the Perl CA bindings weren't working properly when the Perl installation was from Conda. This release also fixed the capr.pl script to handle the INT64 data types, and to be able to properly handle missing fields, as happens if the IOC is running an older EPICS version for example.
The implementation of the epicsMessageQueue
used on
RTEMS has switched from the native RTEMS-specific one to the EPICS
generic version, avoiding a bug in the RTEMS Kernel message queue
code.
Historically, there have been very few restrictions on which characters may be present in record and alias names. Base 3.14.12.3 added a warning for names containing space, single or double quote, period/dot, or dollar sign.
Bad character ' ' in record name "bad practice"
7.0.4.1 Turns this warning into an error, and adds a new warning if a record name begins with a minus, plus, left square bracket, or left curly bracket.
The following launchpad bugs have fixes included in this release:
Internally, the Com and ca libraries now express dllimport/export
(Windows) and symbol visibility (GCC) using library-specific macros (eg.
LIBCOM_API
) instead of the macros
epicsShareFunc
, epicsShareClass
,
epicsShareDef
etc. that are defined in the
shareLib.h
header. This change may affect some user code
which uses the epicsShare*
macros without having explicitly
included the shareLib.h
header themselves. Such code should
be changed to include shareLib.h
directly.
A new helper script makeAPIheader.pl
and build rules to
generate a library-specific *API.h
header file has been
added. Run makeAPIheader.pl -h
for information on how to
use this in your own applications, but note that the resulting sources
will not be able to be compiled using earlier versions of EPICS
Base.
At the iocShell prompt help <cmd>
now prints a
descriptive usage message for many internal IOCsh commands in addition
to the command parameters. Try help *
to see all commands,
or a glob pattern such as help db*
to see a subset.
External code may provide usage messages when registering commands
using a new const char *usage
member of the
iocshFuncDef
structure. The iocsh.h
header
also now defines a macro IOCSHFUNCDEF_HAS_USAGE
which can
be used to detect Base versions that support this feature at
compile-time.
configure/RELEASE
files are parsed by both GNUmake and
the convertRelease.pl
script. While GNUmake is quite
relaxed about what characters may be used in a RELEASE variable name,
the convertRelease.pl
script parser has only recognized
variable names that match the Perl regular expression \w+
,
i.e. upper and lower-case letters, digits and underscore characters.
The script has been modified so now RELEASE variable names must start
with a letter or underscore, and be followed by any number of letters,
digits, underscore or hyphen characters, matching the regular expression
[A-Za-z_][A-Za-z_0-9-]*
. The hyphen character
-
was not previously allowed and if used would have
prevented a build from finding include files and libraries in any module
using that in its RELEASE variable name.
This change does disallow names that start with a digit which used to
be allowed, but hopefully nobody has been relying on that ability. The
regular expression used for names can be found in the file
src/tools/EPICS/Release.pm
and can be adjusted locally if
necessary.
On *NIX targets caRepeater will now partially daemonize by redirecting stdin/out/err to /dev/null. This prevents caRepeater from inheriting the stdin/out of a process, like caget, which has spawned it in the background. This has been known to cause problems in some cases when caget is itself being run from a shell script.
caRepeater will now understand the -v
argument to retain
stdin/out/err which may be necessary to see any error messages it may
emit.
state
record
deprecatedIOCs now emit a warning when a database file containing the
state
record is loaded. This record has been deprecated for
a while and will be removed beginning with EPICS 7.1. Consider using the
stringin
record instead.
The record types in Base now define their device support entry table (DSET) structures in the record header file. While still optional, developers of external support modules are encouraged to start converting their code to use the record's new definitions instead of the traditional approach of copying the structure definitions into each source file that needs them. By following the instructions below it is still possible for the converted code to build and work with older Base releases.
This would also be a good time to modify the device support to use the type-safe device support entry tables that were introduced in Base-3.16.2 -- see this entry below for the description of that change, which is also optional for now.
Look at the aiRecord for example. Near the top of the generated
aiRecord.h
header file is a new section that declares the
aidset
:
/* Declare Device Support Entry Table */
struct aiRecord;
typedef struct aidset {
;
dset commonlong (*read_ai)(struct aiRecord *prec);
long (*special_linconv)(struct aiRecord *prec, int after);
} aidset;
#define HAS_aidset
Notice that the common members (number
,
report()
, init()
, init_record()
and get_ioint_info()
don't appear directly but are included
by embedding the dset common
member instead. This avoids
the need to have separate definitions of those members in each record
dset, but does require those members to be wrapped inside another set of
braces {}
when initializing the data structure for the
individual device supports. It also requires changes to code that
references those common members, but that code usually only appears
inside the record type implementation and very rarely in device
supports.
An aiRecord device support that will only be built against this or later versions of EPICS can now declare its dset like this:
= {
aidset devAiSoft { 6, NULL, NULL, init_record, NULL },
, NULL
read_ai};
(dset, devAiSoft); epicsExportAddress
However most device support that is not built into EPICS itself will
need to remain compatible with older EPICS versions, which is why the ai
record's header file also declares the preprocessor macro
HAS_aidset
. This makes it easy to define the
aidset
in the device support code when it's needed, and not
when it's provided in the header:
#ifndef HAS_aidset
typedef struct aidset {
;
dset commonlong (*read_ai)(aiRecord *prec);
long (*special_linconv)(aiRecord *prec, int after);
} aidset;
#endif
= {
aidset devAiSoft { 6, NULL, NULL, init_record, NULL },
, NULL
read_ai};
(dset, devAiSoft); epicsExportAddress
The above typedef struct
declaration was copied directly
from the new aiRecord.h file and wrapped in the
#ifndef HAS_aidset
conditional.
This same pattern should be followed for all record types except for
the lsi, lso and printf record types, which have published their device
support entry table structures since they were first added to Base but
didn't previously embed the dset common
member. Device
support for these record types therefore can't use the dset name since
the new definitions are different from the originals and will cause a
compile error, so this pattern should be used instead:
#ifndef HAS_lsidset
struct {
;
dset commonlong (*read_string)(lsiRecord *prec);
}
#else
lsidset#endif
= {
devLsiEtherIP {5, NULL, lsi_init, lsi_init_record, get_ioint_info},
lsi_read};
IMPORTANT NOTE: Some record types in this release will not be compatible with device support binaries compiled against earlier versions of those record types, because importing the record documentation from the EPICS Wiki as described below also modified the order of some of the fields in the record definitions. As long as all support modules and IOCs are rebuilt from source after updating them to use this release of EPICS Base, these changes should not have any affect.
On supported targets (Linux, Mac, Windows) logClient will attempt to avoid dropping undelivered log messages when the connection to the log server is closed/reset.
Many internal timers and delay calculations use a monotonic clock epicsTimeGetMonotonic() instead of the realtime epicsTimeGetCurrent(). This is intended to make IOCs less susceptible to jumps in system time.
on error ...
A new statement is added to enable IOC shell commands to signal error conditions, and for scripts to respond. This first is through the new function
int iocshSetError(int err);
A script may be prefixed with eg. "on error break" to stop at the failed command.
on error continue | break | wait [value] | halt
A suggested form for IOC shell commands is:
static void doSomethingCallFunc(const iocshArgBuf *args)
{
(doSomething(...)); /* return 0 == success */
iocshSetError}
Allows built trees to be copied or moved without invalidating RPATH entires.
The LINKER_USE_RPATH
Makefile variable (see
configure/CONFIG_SITE
) may be set to YES
,
NO
, and a new third option ORIGIN
. This is
limited to targets using the ELF executable format (eg. Linux).
When LINKER_USE_RPATH=ORIGIN
, the variable
LINKER_ORIGIN_ROOT
is set to one of the parents of the
build directory. Any libraries being linked to which are found under
this root will have a relative RPATH entry. Other libraries continue to
result in absolute RPATH entries.
An effect of this might change a support library from being linked
with -Wl,-rpath /build/epics-base/lib/linux-x86
to being
linked with
-Wl,-rpath \$ORIGIN/../../../epics-base/lib/linux-x86
if
the support module directory is /build/mymodule
and
LINKER_ORIGIN_ROOT=/build
.
The API functions epicsGetExecDir()
and
epicsGetExecName()
are also added to
osiFileName.h
to provide runtime access to the directory or
filename of the executable with which the process was started.
Previously, setting STATIC_BUILD=NO
implied
LINKER_USE_RPATH=NO
. This is no longer the case. Setting
LINKER_USE_RPATH=YES
will always emit RPATH entries. This
was found to be helpful when linking against some 3rd party libraries
which are only available as shared objects.
Host names given in a HAG
entry of an IOC's Access
Security Configuration File (ACF) have to date been compared against the
hostname provided by the CA client at connection time, which may or may
not be the actual name of that client. This allows rogue clients to
pretend to be a different host, and the IOC would believe them.
An option is now available to cause an IOC to ask its operating
system to look up the IP address of any hostnames listed in its ACF
(which will normally be done using the DNS or the
/etc/hosts
file). The IOC will then compare the resulting
IP address against the client's actual IP address when checking access
permissions at connection time. This name resolution is performed at ACF
file load time, which has a few consequences:
If the DNS is slow when the names are resolved this will delay the process of loading the ACF file.
If a host name cannot be resolved the IOC will proceed, but this host name will never be matched.
Any changes in the hostname to IP address mapping will not be picked up by the IOC unless and until the ACF file gets reloaded.
Optionally, IP addresses may be added instead of, or in addition to, host names in the ACF file.
This feature can be enabled before iocInit
with
var("asCheckClientIP",1)
or with the VxWorks target shell use
= 1 asCheckClientIP
epicsThreadCreateOpt()
A new routine epicsThreadCreateOpt()
is an alternative
to epicsThreadCreate()
which takes some arguments via a
structure (struct epicsThreadOpts
) to allow for future
extensions.
typedef struct epicsThreadOpts {
unsigned int priority;
unsigned int stackSize;
unsigned int joinable;
} epicsThreadOpts;
#define EPICS_THREAD_OPTS_INIT { \
epicsThreadPriorityLow, epicsThreadStackMedium, 0}
(const char * name,
epicsThreadId epicsThreadCreateOpt, void * parm, const epicsThreadOpts *opts); EPICSTHREADFUNC funptr
The final opts
parameter may be NULL
to use
the default values of thread priority (low) and stack size (medium).
Callers wishing to provide alternative settings for these thread options
or to create a joinable thread (see below) should create and pass in an
epicsThreadOpts
structure as shown below. Always initialize
one of these structures using the EPICS_THREAD_OPTS_INIT
macro to ensure that any additional fields that get added in the future
are set to their default values.
void startitup(void) {
= EPICS_THREAD_OPTS_INIT;
epicsThreadOpts opts ;
epicsThreadId tid
.priority = epicsThreadPriorityMedium;
opts= epicsThreadCreateOpt("my thread", &threadMain, NULL, &opts);
tid }
C or C++ Code that also needs to build on earlier versions of Base
can use #ifdef EPICS_THREAD_OPTS_INIT
to determine whether
the epicsThreadCreateOpt()
API is available on this Base
version.
The stackSize
member of the epicsThreadOpts
structure and the equivalent parameters to the
epicsThreadCreate()
and
epicsThreadMustCreate()
routines can now be passed either
one of the epicsThreadStackSizeClass
enum values or a value
returned from the epicsThreadGetStackSize()
routine.
epicsThreadMustJoin()
If the new joinable
flag of an
epicsThreadOpts
structure is non-zero (the default value is
zero), the new API routine epicsThreadMustJoin()
must be called with the thread's epicsThreadId
when/after the thread exits, to free up thread resources. This function
will block until the thread's main function has returned, allowing the
parent to wait for its child thread. The child's
epicsThreadId
will no longer be valid and should not be
used after the epicsThreadMustJoin()
routine returns.
A thread that was originally created with its joinable flag set may
itself call epicsThreadMustJoin()
, passing in its own
epicsThreadId. This marks the thread as no longer being joinable, so it
will then free the thread resources itself when its main function
returns. The epicsThreadId
of a thread that is not joinable
gets invalidated as soon as its main function returns.
Previously IOC executables that made calls to devLib routines would fail to link when built for some non-VME based RTEMS targets, which would have to be explicitly filtered out by sites that build Base for those targets. This fix makes that no longer necessary, all RTEMS targets should now link although the IOC won't be able to be used with the VME I/O on those systems (that we don't have VMEbus I/O support for in libCom).
epicsTimeGetCurrent()
optimizationAdd a fast path to epicsTimeGetCurrent() and related calls in the common case where only the default OS current time provider is registered. This path does not take the global mutex guarding the time providers list, potentially reducing lock contention.
The size of the queue used by dbEvent to push monitor updates has
been slightly increased based on DBR_TIME_DOUBLE
to better
fill an ethernet frame. This may result in slightly fewer, but larger
frames being sent.
Report NOBT as "precision" through the dbAccess API. This is not accessible through CA, but is planned to be used through QSRV.
The GNUmake build targets cvsclean
and
depclean
are now available from any directory; previously
they were only available from application top directories.
The approach that EPICS Base uses for building submodules inside
the parent module looks useful for support modules too. The rules for
building submodules have been modified and extracted into a new
RULES_MODULES
file, so a support module will be able to use
them too without having to copy them into its own
modules/Makefile
. There are some specific requirements that
support modules and their submodules must follow, which are described as
comments in the new base/configure/RULES_MODULES
file
itself.
EPICS_BASE_VERSION
Update Policy changeIn the past, a build of EPICS using sources checked out from the repository branch between official releases would have shown the version number of the previous release, followed by a -DEV suffix, for example 7.0.2.1-DEV.
The policy that controls when the number gets updated has been changed, and now immediately after a release has been tagged the version number will be updated to the next patch release version, plus the -DEV suffix as before. Thus following 7.0.2.2 the version number will show as 7.0.2.3-DEV. This does not require the next official release to be numbered 7.0.2.3 though, it could become 7.0.3 or even 7.1.0 if the changes incorporated into it are more substantial than bug fixes.
CLOCK_MONOTONIC_RAW
from posix/osdMonotonic.cTurns out this is ~10x slower to query than
CLOCK_MONOTONIC
.
The linker flag -flat_namespace
has been restored for
creating shared libraries, although not for loadable libraries
(bundles). This was required for building using the latest versions of
Apple XCode.
DB_LINK
loop
breakingA regression was introduced in 7.0.2 which caused record chains with
loops to be incorrectly broken. Processing should be skipped when a
DB_LINK
with Process Passive (PP) closes a loop to a
synchronous record.
Instead in 7.0.2 the targeted record would be processed if processing
began with a remote action (or some other caller of
dbPutField()
). This would result in the loop running a
second time. The loop would be broken on the second iteration.
Support for some obsolete dbStaticLib Database Configuration Tool (DCT) APIs was removed some time ago, but vestiges of them still remained. The following routines and macros and have now finally been removed:
int dbGetFieldType(DBENTRY *pdbentry)
int dbGetLinkType(DBENTRY *pdbentry)
DCT_STRING
DCT_INTEGER
DCT_REAL
DCT_MENU
DCT_MENUFORM
DCT_INLINK
DCT_OUTLINK
DCT_FWDLINK
DCT_NOACCESS
DCT_LINK_CONSTANT
DCT_LINK_FORM
DCT_LINK_PV
dbhcr
before
iocInit
The dbhcr
command used to work before
iocInit
as well as afterwards. It displays all records that
have hardware addresses (VME_IO
, CAMAC_IO
,
GPIB_IO
, INST_IO
etc.) but stopped working if
run before iocInit due to the rewrite of the link address parser code in
dbStaticLib. This release fixes that issue, although in some cases the
output may be slightly different than it used to be.
The list of tracked bugs fixed in this release can be found on the Launchpad Milestone page for EPICS Base 7.0.2.
The four separate Git branches core/master
,
libcom/master
, ca/master
and
database/master
have been recombined into one branch called
7.0
. Keeping these as 4 separate branches in the same
repository made it impossible to create merge requests that contained
changes in more than one of these modules. The layout of the source
files has not changed at all however, so the source code for libcom, ca
and the database are still found separately under the module
subdirectory.
A failure when fetching the simulation mode through SIML
will not put the record into INVALID alarm state anymore. Instead, as
long as the record's current alarm severity (SEVR
)is
NO_ALARM
, its alarm status (STAT
) will be set
to LINK_ALARM
without increasing the severity. This allows
clients to get some notification of a failing or bad SIML
link without otherwise affecting record processing.
dbVerify()
has been restored to dbStaticLibThis routine was removed in Base-3.16.1 but has been reimplemented in this release by special request. Note that the error message strings that it returns when verification fails have changed, but are still designed for display to the user.
Records that support simulation mode have two new fields,
SSCN
(Simulation Scan Mode) and SDLY
(Simulation Delay). SSCN
is a menu field that provides an
alternate value for the SCAN
field to be used while the
record is in simulation mode. This is especially useful for I/O scanned
records, for which simulation mode was not working at all. Setting
SDLY
to a positive value makes the record process
asynchronously in simulation mode, with the second stage processing
happening after the specified time (in seconds).
This change permits IOCs to be built that omit the CA server (RSRV)
by removing its registrar entry which is now provided in the new
rsrv.dbd
file. Other server layers can be built into the
IOC (alongside RSRV or in place of it) by registering them in a similar
manner. The dbServer API is documented with Doxygen comments in the
header file.
Specific IOC server layers can be disabled at runtime by adding their
name to the environment variable EPICS_IOC_IGNORE_SERVERS
(separated by spaces if more than one should be ignored).
EPICS 7.0.1 contains the IOC Database, RSRV server and the Channel Access client code from EPICS Base 3.16.1 along with all the original record types and soft device support, but GDD and the Portable Channel Access Server have been unbundled and are now available separately. In their place we have brought in the more recently written EPICS V4 C++ libraries (collectively referred to as the PVA modules). The directory tree for EPICS is somewhat larger as a result, and the original structure of the Base directories has been split into 4 separate Git repositories. External modules should build against this new structure with little or no changes needed, except that some allowance may be needed for the merging of the V4 modules.
There should be rather more description and documantation of these changes than is currently available, but as developers we generally much prefer to write code than documentation. Send questions to the tech-talk mailing list and we'll be happy to try and answer them!
The list of tracked bugs fixed in this release can be found on the Launchpad Milestone page for EPICS Base 3.16.2.
Two new iocsh commands and some associated underlying APIs have been
added to show the state of the queues that feed the three callback tasks
and the scanOnce task, including a high-water mark which can optionally
be reset. The new iocsh commands are callbackQueueShow
and
scanOnceQueueShow
; both take an optional integer argument
which must be non-zero to reset the high-water mark.
NUM_TIME_EVENTS
Event numbers greater than or equal to NUM_TIME_EVENTS
are now allowed if supported by the registered event time provider,
which must provide its own advancing timestamp validation for such
events.
Time events numbered 0 through (NUM_TIME_EVENTS-1)
are
still validated by code in epicsGeneralTime.c that checks for advancing
timestamps and enforces that restriction.
Type-safe versions of the device and driver support structures
dset
and drvet
have been added to the devSup.h
and drvSup.h headers respectively. The original structure definitions
have not been changed so existing support modules will still build
normally, but older modules can be modified and new code written to be
compatible with both.
The old structure definitions will be replaced by the new ones if the
macros USE_TYPED_DSET
and/or USE_TYPED_DRVET
are defined when the appropriate header is included. The best place to
define these is in the Makefile, as with the USE_TYPED_RSET
macro that was introduced in Base-3.16.1 and described below. See the
comments in devSup.h for a brief usage example, or look at this
commit to the ipac module to see a module conversion.
A helper function DBLINK* dbGetDevLink(dbCommon *prec)
has also been added to devSup.h which fetches a pointer to the INP or
OUT field of the record.
This release includes the ability to run the EPICS unit tests built
for a special version of the RTEMS-pc386 target architecture on systems
that have an appropriate QEMU emulator installed
(qemu-system-i386
). It is also now possible to create
sub-architectures of RTEMS targets, whereas previously the EPICS target
architecture name had to be RTEMS-$(RTEMS_BSP)
.
The new target RTEMS-pc386-qemu
builds binaries that can
be run in the qemu-system-i386
PC System emulator. This
target is a derivative of the original RTEMS-pc386
target
but with additional software to build an in- memory file-system, and
some minor modifications to allow the unit tests to work properly under
QEMU. When this target is enabled, building any of the make targets that
cause the built-in self-tests to be run (such as
make runtests
) will also run the tests for RTEMS using
QEMU.
To allow the new 3-component RTEMS target name, the EPICS build
system for RTEMS was modified to allow a
configure/os/CONFIG.Common.<arch>
file to set the
RTEMS_BSP
variable to inform the build what RTEMS BSP to
use. Previously this was inferred from the value of the T_A
make variable, but that prevents having multiple EPICS targets that
build against the same BSP. All the included RTEMS target configuration
files have been updated; build configuration files for out-of-tree RTEMS
targets will continue to work as the original rules are used to set
RTEMS_BSP
if it hasn't been set when needed.
This release adds three new link types: "state", "debug" and "trace".
The "state" link type gets and puts boolean values from/to the dbState
library that was added in the 3.15.1 release. The "debug" link type sets
the jlink::debug
flag in its child link, while the "trace"
link type also causes the arguments and return values for all calls to
the child link's jlif and lset routines to be printed on stdout. The
debug flag can no longer be set using an info tag. The addition of the
"trace" link type has allowed over 200 lines of conditional diagnostic
printf() calls to be removed from the other link types.
The "calc" link type can now be used for output links as well as input links. This allows modification of the output value and even combining it with values from other input links. See the separate JSON Link types document for details.
A new start_child()
method was added to the end of the
jlif interface table.
The lset
methods have now been properly documented in
the dbLink.h header file using Doxygen annotations, although we do not
run Doxygen on the source tree yet to generate API documentation.
Link types that utilize child links must now indicate whether the
child will be used for input, output or forward linking by the return
value from its parse_start_map()
method. The
jlif_key_result
enum now contains 3 values
jlif_key_child_inlink
, jlif_key_child_outlink
and jlif_key_child_fwdlink
instead of the single
jlif_key_child_link
that was previously used for this.
Some additional build rules have been added to help debug
configuration problems with the build system. Run
make show-makefiles
to get a sorted list of all the files
that the build system includes when building in the current
directory.
A new pattern rule for PRINT.%
can be used to show the
value of any GNUmake variable for the current build directory (make sure
you are in the right directory though, many variables are only set when
inside the O.<arch>
build directory). For example
make PRINT.T_A
will display the build target architecture
name from inside a O.<arch>
directory but the
variable will be empty from an application top or src directory.
make PRINT.EPICS_BASE
will show the path to Base from any
EPICS application directory though.
The IOC contains a mechanism involving the PUTF and RPRO fields of each record to ensure that if a record is busy when it receives a put to one of its fields, the record will be processed again to ensure that the new field value has been correctly acted on. Until now that mechanism only worked if the put was to the asynchronous record itself, so puts that were chained from some other record via a DB link did not cause reprocessing.
In this release the mechanism has been extended to propagate the PUTF
state across DB links until all downstream records have been
reprocessed. Some additional information about the record state can be
shown by setting the TPRO field of an upstream record, and even more
trace data is displayed if the debugging variable
dbAccessDebugPUTF
is set in addition to TPRO.
A new iocsh command dbli
lists the info fields defined
in the database, and can take a glob pattern to limit output to specific
info names. The newly added dbStaticLib function
dbNextMatchingInfo()
iterates through the info fields
defined in the current record, and is used to implement the new
command.
dbpr
command enhancedThe "DataBase Print Record" command dbpr
now generates
slightly better output, with more field types having their own display
methods. This release also includes additional protection against buffer
overflows while printing long links in dbpr
, and corrects
the output of long strings from the dbgf
command.
The VAL fields and related fields of these records are now
DBF_LONG
. (Not DBF_ULONG
in order to prevent
Channel Access from promoting them to DBF_DOUBLE
.)
Additional bit fields B10
...B1F
have been
added.
Device support that accesses VAL
or the bit fields
directly (most don't) and aims for compatibility with old and new
versions of these records should use at least 32 bit integer types to
avoid bit loss. The number of bit fields can be calculated using
8 * sizeof(prec->val)
which is correct in both
versions.
The epicsReadline refactoring work described below unfortunately disabled the VxWorks implementation of the osdReadline.c API that uses ledlib for command editing and history. This functionality has now been restored, see Launchpad bug #1741578.
Constant links can now hold 64-bit integer values, either as scalars or arrays. Only base 10 is supported by the JSON parser though, the JSON standard doesn't allow for hexadecimal numbers.
The third-party YAJL library that has been included in libCom for
several years has been upgraded to version 2.1.0 and several bugs fixed.
This has an updated API, requiring any code that uses it to parse its
own JSON files to be modified to match. The changes are mainly that it
uses size_t
instead unsigned int
for string
lengths, but it also uses long long
instead of
long
for JSON integer values, which was the main motivation
for the upgrade.
The self-tests that YAJL comes with have been imported and are now
run as an EPICS Unit Test program, and the JSON syntax accepted by the
parser was extended to permit trailing commas in both arrays and maps.
The difference between the old and new YAJL APIs can be detected at
compile time by looking for the macro EPICS_YAJL_VERSION
which is defined in the yajl_common.h
header file along
with a brief description of the API changes.
A new optional parameter can be given when specifying a calc JSON
link. The time
parameter is a string containing a single
letter A..L
that selects one of the input links to be used
for the timestamp of calculation if requested. The timestamp will be
fetched atomically with the value from the chosen input link (providing
that input link type supports the readLocked() method).
A soft channel output record with the OUT link unset uses the
CONSTANT link type. The new link type code was causing some soft channel
device supports to return an error status from the write method of that
link type, which would cause a ca_put()
operation to such a
record to generate an exception. This has been silenced by giving the
constant link types a dummy putValue method. A new test program has been
added to prevent regressions of this behaviour.
In the 3.16.1 release a crash can occur in the IOC's RSRV server when a large array is made even larger; the previous array buffer was not being released correctly. See Launchpad bug #1706703.
The IOC now supports the 64-bit integer field types
DBF_INT64
and DBF_UINT64
, and there are new
record types int64in
and int64out
derived from
the longin
and longout
types respectively that
use the DBF_INT64
data type for their VAL and related
fields. The usual range of Soft Channel device support are included for
these new record types.
All internal IOC APIs such as dbAccess can handle the new field types
and their associated request values DBR_INT64
and
DBR_UINT64
, which are implemented using the
epicsInt64
and epicsUInt64
typedef's from the
epicsTypes.h
header.
The waveform record type has been updated to support these new field
types. All waveform device support layers must be updated to
recognize the new type enumeration values, which had to be
inserted before the FLOAT
value in the enum
dbfType
and in menuFtype
. C or C++ code can
detect at compile-time whether this version of base provides 64-bit
support by checking for the presence of the DBR_INT64
macro
as follows (Note that DBF_INT64
is an enum tag and not a
preprocessor macro):
#ifdef DBR_INT64
/* Code where Base has INT64 support */
#else
/* Code for older versions */
#endif
If the code uses the old db_access.h
types (probably
because it's calling Channel Access APIs) then it will have to test
against the EPICS version number instead, like this:
#include <epicsVersion.h>
#ifndef VERSION_INT
# define VERSION_INT(V,R,M,P) ( ((V)<<24) | ((R)<<16) | ((M)<<8) | (P))
#endif
#ifndef EPICS_VERSION_INT
# define EPICS_VERSION_INT VERSION_INT(EPICS_VERSION, EPICS_REVISION, EPICS_MODIFICATION, EPICS_PATCH_LEVEL)
#endif
#if EPICS_VERSION_INT >= VERSION_INT(3,16,1,0)
/* Code where Base has INT64 support */
#else
/* Code for older versions */
#endif
Channel Access does not (and probably never will) directly support
64-bit integer types, so the new field types are presented to the CA
server as DBF_DOUBLE
values. This means that field values
larger than 2^52 (0x10_0000_0000_0000 = 4503599627370496) cannot be
transported over Channel Access without their least significant bits
being truncated. The EPICS V4 pvAccess network protocol can
transport 64-bit data types however, and a future release of the pvaSrv
module will connect this ability to the fields of the IOC.
Additional 64-bit support will be provided in later release. For instance the JSON parser for the new Link Support feature only handles integers up to 32 bits wide, so constant array initializer values cannot hold larger values in this release.
EPICS_CA_MCAST_TTL
A new environment parameter EPICS_CA_MCAST_TTL
is used
to set the Time To Live (TTL) value of any IP multi-cast CA search or
beacon packets sent.
EPICS_CA_MAX_ARRAY_BYTES
is optionalA new environment parameter EPICS_CA_AUTO_ARRAY_BYTES
is
now used by libca and RSRV (CA clients and the IOC CA server). The
default is equivalent to setting
EPICS_CA_AUTO_ARRAY_BYTES=YES
which removes the need to set
EPICS_CA_MAX_ARRAY_BYTES
and always attempts to allocate
sufficiently large network buffers to transfer large arrays properly
over the network. In this case the value of the
EPICS_CA_MAX_ARRAY_BYTES
parameter is ignored.
Explicitly setting EPICS_CA_AUTO_ARRAY_BYTES=NO
will
continue to honor the buffer setting in
EPICS_CA_AUTO_ARRAY_BYTES
as in previous releases.
The default setting for EPICS_CA_AUTO_ARRAY_BYTES
can be
changed by adding the line
EPICS_CA_AUTO_ARRAY_BYTES=NO
to the configure/CONFIG_SITE_ENV
file before building
Base. Sites that wish to override this only for specific IOC
architectures can create new files for each architecture named
configure/os/CONFIG_SITE_ENV.<target-arch>
with the
above setting in before building Base. The configuration can also be
explicitly changed by setting the environment variable in the IOC's
startup script, anywhere above the iocInit
line.
The PCAS server (used by the PV Gateway and other CA servers) now
always behaves as if EPICS_CA_AUTO_ARRAY_BYTES
is set to
YES
(it ignores the configuration parameter and environment
variable).
Drop support for CA clients advertising protocol versions less than 4.
This effects clients from Base older than 3.12.0-beta1. Newer clients will continue to be able to connect to older servers. Older clients will be ignored by newer servers.
This allows removal of UDP echo and similar protocol features which are not compatible with secure protocol design practice.
The subArray record can now be used as a lookup-table from a constant array specified in its INP field. For example:
record(subArray, "powers-of-2") {
field(FTVL, "LONG")
field(MALM, 12)
field(INP, [1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048])
field(INDX, 0)
field(NELM, 1)
}
The INDX field selects which power of 2 to set the VAL field to. In previous releases the INP field would have to have been pointed to a separate waveform record that was initialized with the array values somehow at initialization time.
Most Soft Channel input device support routines have supported fetching the timestamp through the INP link along with the input data. However before now there was no guarantee that the timestamp provided by a CA link came from the same update as the data, since the two were read from the CA input buffer at separate times without maintaining a lock on that buffer in between. This shortcoming could be fixed as a result of the new link support code, which allows code using a link to pass a subroutine to the link type which will be run with the link locked. The subroutine may make multiple requests for metadata from the link, but must not block.
A major new feature introduced with this release of EPICS Base is an Extensible Link Type mechanism, also known as Link Support or JSON Link Types. This addition permits new kinds of link I/O to be added to an IOC in a similar manner to the other extension points already supported (e.g. record, device and driver support).
A new link type must implement two related APIs, one for parsing the
JSON string which provides the link address and the other which
implements the link operations that get called at run-time to perform
I/O. The link type is built into the IOC by providing a new
link
entry in a DBD file.
This release contains two new JSON link types, const
and
calc
:
The const
link type is almost equivalent to the old
CONSTANT link type with the updates described below to accept arrays and
strings, except that there is no need to wrap a scalar string constant
inside array brackets since a constant string will never be confused
with a PV name.
The calc
link type allows CALC expressions to be
used to combine values from other JSON links to produce its value. Until
additional JSON link types are created though, the calc
link type has little practical utility as it can currently only fetch
inputs from other calc
links or from const
links.
field(INP, {calc:{expr:"A+B+1",
args:[5, # A
{const:6}] # B
}
}
)
The new link types are documented in a separate document that gets
generated at build time and installed as
html/links.html
.
JSON_LINK
The API to allow device support to use JSON addresses is currently
incomplete; developers are advised not to try creating device support
that specifies a JSON_LINK
address type.
For link fields in external record types and soft device support to be able to use the new link types properly, various changes are required to utilize the new Link Support API as defined in the dbLink.h header file and outlined below. The existing built-in Database and Channel Access link types have been altered to implement the link APIs, so will work properly after these conversions:
recGblInitConstantLink()
unconditional on the link type, i.e. change this code:if (prec->siml.type == CONSTANT) {
(&prec->siml, DBF_USHORT, &prec->simm);
recGblInitConstantLink}
into this:
(&prec->siml, DBF_USHORT, &prec->simm); recGblInitConstantLink
Note that recGblInitConstantLink()
still returns TRUE if
the field was successfully initialized from the link (implying the link
is constant). This change will work properly with all Base releases
currently in use.
dbLinkIsConstant()
instead, which
returns TRUE for constant or undefined links, FALSE for links whose
dbGetLink()
routine may return different values on
different calls. For example this:if (prec->dol.type != CONSTANT)
should become this:
if (!dbLinkIsConstant(&prec->dol))
When the converted software is also required to build against older versions of Base, this macro definition may be useful:
#define dbLinkIsConstant(lnk) ((lnk)->type == CONSTANT)
if (prec->inp.type == CA_LINK)
will still compile and run, but will only work properly with the old CA link type. To operate with the new extensible link types such code must be modified to use the new generic routines defined in dbLink.h and should never attempt to examine or modify data inside the link. After conversion the above line would probably become:
if (dbLinkIsVolatile(&prec->inp))
A volatile link is one like a Channel Access link which may disconnect and reconnect without notice at runtime. Database links and constant links are not volatile; unless their link address is changed they will always remain in the same state they started in. For compatibility when building against older versions of Base, this macro definition may be useful:
#define dbLinkIsVolatile(lnk) ((lnk)->type == CA_LINK)
dbIsLinkConnected()
which will only return TRUE
for a volatile link that is currently connected. Code using the older
dbCa API returning this information used to look like this:= dbCaIsLinkConnected(plink); stat
which should become:
= dbIsLinkConnected(plink); stat
Similar changes should be made for calls to the other dbCa routines.
Previously a constant link (i.e. a link that did not point to another PV, either locally or over Channel Access) was only able to provide a single numeric value to a record initialization; any string given in a link field that was not recognized as a number was treated as a PV name. In this release, constant links can be expressed using JSON array syntax and may provide array initialization of values containing integers, doubles or strings. An array containing a single string value can also be used to initialize scalar strings, so the stringin, stringout, lsi (long string input), lso (long string output), printf, waveform, subArray and aai (analog array input) record types and/or their soft device supports have been modified to support this.
Some examples of constant array and string initialized records are:
record(stringin, "const:string") {
field(INP, ["Not-a-PV-name"])
}
record(waveform, "const:longs") {
field(FTVL, LONG)
field(NELM, 10)
field(INP, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
}
record(aai, "const:doubles") {
field(FTVL, DOUBLE)
field(NELM, 10)
field(INP, [0, 1, 1.6e-19, 2.718, 3.141593])
}
record(aSub, "select") {
field(FTA, STRING)
field(NOA, 4)
field(INPA, ["Zero", "One", "Two", "Three"])
field(FTB, SHORT)
field(NOB, 1)
field(FTVA, STRING)
field(NOVA, 1)
field(SNAM, "select_asub")
}
Reminder: Link initialization with constant values normally only occurs at record initialization time. The calcout and printf record types are the only exceptions in the Base record types to this rule, so it is generally not useful to change a const link value after iocInit.
A database file can now provide a "relaxed JSON" value for a database field value or an info tag. Only a few field types can currently accept such values, but the capability is now available for use in other places in the future. When writing to a JSON-capable field at run-time however, only strictly compliant JSON may be used (the dbStaticLib parser rewrites relaxed JSON values into strict JSON before passing them to the datase for interpretation, where the strict rules must be followed).
"Relaxed JSON" was developed to maximize compatibility with the previous database parser rules and reduce the number of double-quotes that would be needed for strict JSON syntax. The parser does accept strict JSON too though, which should be used when machine-generating database files. The differences are:
Strings containing only the characters
a-z A-Z 0-9 _ - + .
do not have to be enclosed in
double-quote characters.
The above rule applies to map keys as well as to regular string values.
The JSON keywords null
, true
and
false
(all lower-case) will be recognized as keywords, so
they must be quoted to use any of these single words as a
string.
Comments may be used, introduced as usual by the #
character and extending to the end of the line.
A JSON field or info value is only enclosed in quotes when the value being provided is a single string, and even here the quotes can be omitted in some cases as described above. The following shows both correct and incorrect excerpts from a database file:
record(ai, math:pi) {
field(INP, {const: 3.14159265358979}) # Correct
field(SIOL, "{const: 3.142857}") # Wrong
info(autosave, { # White-space and comments are allowed
fields:[DESC, SIMM],
pass0:[VAL]
}) # Correct
}
Note that the record, field and info-tag names do not accept
JSON values, so they follows the older bareword rules for quoting where
the colon :
and several additional characters are legal in
a bareword string. Only the value (after the comma) is parsed as JSON.
The autosave module has not been modified to accept JSON syntax, the
above is only an example of how JSON might be used.
The way comments are parsed by the iocsh interpreter has changed. The
interpreter can be selectively disabled from echoing comments coming
from a script by starting those lines with #-
rather than
just #
.
The table of record support functions (rset methods for short) no
longer has entries of type RECSUPFUN
(which says: any
number and type of arguments). Instead, rset methods are now typed by
default. The RECSUPFUN
typedef has been deprecated and
casts to it as well as using the untyped struct rset
will
create compilation warnings.
Existing code (e.g. external record supports) will generate such warnings when compiled against this version of Base, but it will work without changes.
For a conversion period, the new typed rset definitions are activated
by defining USE_TYPED_RSET
, preferably by setting
USR_CPPFLAGS += -DUSE_TYPED_RSET
inside a Makefile. After
activating the new typed rset in this way and making the following
changes, the result should still compile and work properly against older
versions of Base.
The first parameter of init_record
and
process
has been changed to struct dbCommon *
.
Record types that use void*
here should be changed to use
struct dbCommon*
, and cast the argument to their own
xxxRecord *
.
When compiled against this release, compiler warnings about incompatible types for the method pointers should be taken seriously. When compiled against older versions of base, such warnings are unavoidable.
Record types written in C++ need to take more drastic measures because of the stricter type checking in C++. To remain compatible with older versions of base you will need to use something like:
#include "epicsVersion.h"
#ifdef VERSION_INT
# if EPICS_VERSION_INT < VERSION_INT(3,16,0,2)
# define RECSUPFUN_CAST (RECSUPFUN)
# else
# define RECSUPFUN_CAST
# endif
#else
# define RECSUPFUN_CAST (RECSUPFUN)
#endif
and then replace (RECSUPFUN)
with
RECSUPFUN_CAST
when initializing the rset. Further changes
might also be needed, e.g. to adapt const
-ness of method
parameters.
The build rules associated with the CapFast-related tools
sch2edif
and e2db
and the database
optimization tool dbst
have been removed, along with the
DB_OPT
build configuration variable.
The compressRecord has a new field BALG
which can select
between FIFO (append) and LIFO (prepend) ordering for insertion of new
elements. FIFO ordering is the default, matching the behviour of
previous versions.
Valgrind is a software debugging suite provided by many Linux distributions. The header valgrind/valgrind.h is now included in, and installed by, Base. When included by a C or C++ source file this header defines some macros which expand to provide hints to the Valgrind runtime. These have no effect on normal operation of the software, but when run using the valgrind tool they can help to find memory leaks and buffer overflows. Suitable hints have been added to several free-lists within libCom, including freeListLib, allowing valgrind to provide more accurate information about the source of potential leaks.
valgrind.h automatically disables itself when the build target is not
supported by the valgrind tool. It can also explicitly be disabled by
defining the macro NVALGRIND
. See
src/libCom/Makefile
for a commented-out example.
As a matter of policy valgrind.h will never be included by any header file installed by Base, so its use will remain purely an implementation detail hidden from application software. Support modules which choose to use valgrind.h are advised to do likewise.
The IOC record locking code has been re-written with an expanded API; global locks are no longer required by the IOC database implementation.
The new API functions center around dbScanLockMany()
,
which behaves like dbScanLock()
applied to an arbitrary
group of records. dbLockerAlloc()
is used to prepare a list
or record pointers, then dbScanLockMany()
is called. When
it returns, all of the records listed may be accessed (in any order)
until dbScanUnlockMany()
is called.
The Application Developer's Guide has been updated to describe the API and implementation is more detail.
Previously a global mutex lockSetModifyLock
was locked
and unlocked during dbScanLock()
, acting as a sequencing
point for otherwise unrelated calls. The new dbLock.c implementation
does not include any global mutex in dbScanLock()
or
dbScanLockMany()
. Locking and unlocking of unrelated lock
sets is now completely concurrent.
A Perl script and Makefile rules have been added to allow modules to generate a C header file with a macro defined with an automatically updated identifier. This is a VCS revision ID (Darcs, Git, Mercurial, Subversion, and Bazaar are supported) or the date/time of the build if no VCS system is in use.
The makeBaseApp example template has been updated with a new device support which makes this identifier visible via a lsi (long string input) record.
The epicsTime routines that used to return epicsTimeERROR now return
a specific S_time_
status value, allowing the caller to
discover the reason for any failure. The identifier
epicsTimeERROR
is no longer defined, so any references to
it in source code will no longer compile. The identifier epicsTimeOK
still exists and has the value 0 as before, so most code that uses these
APIs can be changed in a way that is backwards-compatible with the
previous return status.
Time providers that have to return a status value and still need to be built with earlier versions of Base can define the necessary status symbols like this:
#include "epicsTime.h"
#ifndef M_time
/* S_time_... status values were not provided before Base 3.16 */
#define S_time_unsynchronized epicsTimeERROR
#define S_time_...whatever... epicsTimeERROR
#endif
The epicsReadline code has been reorganized to allow the commandline
history editor to be disabled at runtime. The
EPICS_COMMANDLINE_LIBRARY
build setting still selects the
preferred editor, but the new IOCSH_HISTEDIT_DISABLE
environment variable can be set at runtime to disable history editing
and make the IOC or other program use the basic editor instead. This is
useful when starting and controlling an IOC from another program through
its stdin and stdout streams since history editors often insert
invisible escape codes into the stdout stream, making it hard to
parse.
Added a new macro callbackGetPriority(prio, callback)
to
the callback.h header and removed the need for dbScan.c to reach into
the internals of its CALLBACK
objects.
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
.
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.
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.
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.
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.
special()
method is now propagated out of the
dbPut()
routine again (broken since 3.15.0).junitfiles
self-test build targetThe 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.)
Issues reported by various static code checkers.
The following launchpad bugs have fixes included in this release:
clock_gettime()
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.
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).
The IOC's error logging system has been updated significantly to fix a number of issues including:
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()
.
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.
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.
The clock_gettime()
routine is no longer used under
MinGW since newer versions don't provide it any more.
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.
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.
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 unforunate 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.
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.
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 WindowsThe 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
.
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.
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.
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).
epicsTempName()
removed from libComThis 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.
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.
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.
-V
optionThis displays the version numbers of EPICS Base and the CA protocol.
The new command epicsEnvUnset varname
can be used to
unset an environment variable.
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.
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.
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.
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
.
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.
osiSockOptMcastLoop_t
and osiSockTestAdded a new OS-independent typedef for multicast socket options, and a test file to check their correct operation.
CONFIG_SITE.local
in BaseThis 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.
EPICS_IOC_LOG_FILE_LIMIT=0
settingThe 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.
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:
EpicsHostArch.pl
script has been rewritten,
and support for a few previously missing host architectures has been
added to it.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.EpicsHostArch.pl
in both places if the
EPICS_HOST_ARCH
environment variable has not been set at
build-time.EPICS_HOST_ARCH
as part of their standard environment will
need to adjust their scripts when they upgrade to this release.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.Site.cshrc
and Site.profile
files have
been renamed to unix.csh
and unix.sh
,
respectively.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.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.
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
.
The following launchpad bugs have fixes included:
assert (pca->pgetNative)
failed in
../dbCa.cca_attach_context()
during
exitsca_clear_subscription()
get_alarm_double()
inconsistent across record
typesRemoved the settings for 2017; fixed the hour of the change for MET.
Initialize the first time-stamp from the first monitor, not the client-side current time in this configuration.
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.
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.
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 resultsThe 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 FormatThe 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 filesThe new make target clean-tests
removes any test result
files from previous test runs. It cleans both TAP and JUnit XML
files.
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.
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 relevent 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.
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.
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.
In addition to the more detailed change descriptions below, the following Launchpad bugs have also been fixed in this release:
dbContextReadNotifyCache()
SIO_GET_INTERFACE_LIST
failed in WindowsWhen 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.
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.
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.
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.
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 synchonize 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.
The build configuration files for builds using the Microsoft
compilers have been updated, although there should be no noticable
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).
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.
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.
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.
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.
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.
promptgroup
/gui_group
field
propertyThe 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.
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.
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.
mlockall()
into its own epicsThread routineSince 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).
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.
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.
ca_get
operations atomicWhen 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.
CONFIG_SITE
variable for running self-testsThe '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.
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.
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).
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).
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.
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.
ipAddrToAsciiAsync()
: Don't try to join the daemon
threadOn 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
epicsTime_localtime()
on WindowsSimpler 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.