This version of EPICS Base has not been released yet.
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 should never be included by any header file installed by Base, so its use will remain purely an internal implementation detail and not be directly visible to application software. Support modules which choose to use valgrind.h are advised to avoid to do likewise.
dbLock.c is re-written with an expanded API, and the removal of global mutex locks.
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/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 all 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.