DPL: add allocator to forward a fair::mq::Message payload by shallow copy

[ehellbar]

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• TPC: make IDC/CMV distribute a pure forwarding device + minor improvements #15583 (3 commits)
• -> DPL: add allocator to forward a fair::mq::Message payload by shallow copy #15577 (2 commits)

[ktf]

don't we already have an helper which does that?

[ehellbar]

I don't see it, at least not for what I am doing here.

I define the getter e.g. in https://github.com/AliceO2Group/AliceO2/pull/15577/changes#diff-5d24f98b5c6098b6ad0a1ab814450dec590c82b86147d85c5a34afa0521171a6R239, where I use the DataRefIndices directly since we anyway calculate them in the InputRecordIterator.

There is https://github.com/AliceO2Group/AliceO2/blob/dev/Framework/Core/include/Framework/DataModelViews.h#L209, but it uses some indices from which the vector indices need to be computed first, so it is more expensive than what I need to do. Or are you referring to something else?

[alibuild]

Error while checking build/O2/fullCI_slc9 for b4570d8 at 2026-07-09 11:36:

## sw/BUILD/O2Physics-latest/log
c++: fatal error: Killed signal terminated program cc1plus
ninja: build stopped: subcommand failed.


## sw/BUILD/o2checkcode-latest/log
--
========== List of errors found ==========
++ GRERR=0
++ grep -v clang-diagnostic-error error-log.txt
++ grep ' error:'
grep: error-log.txt: binary file matches
++ GRERR=1
++ [[ 1 == 0 ]]
++ mkdir -p /sw/INSTALLROOT/d0a30e7fd80d14a4ff23a1cd3c6ddbd761ac1cbc/slc9_x86-64/o2checkcode/1.0-local113/etc/modulefiles
++ alibuild-generate-module
+ HAS_BIN=
+ HAS_LIB=
+ HAS_CMAKE=
+ HAS_ROOT=
+ '[' 0 '!=' 0 ']'
+ cat
+ printf 'if ![ is-loaded '\''BASE/1.0'\'' ] {\n module load BASE/1.0\n}'
+ echo 'BUILD_REQUIRES=CMake alibuild-recipe-tools defaults-release'
BUILD_REQUIRES=CMake alibuild-recipe-tools defaults-release
+ FULL_BUILD_REQUIRES='defaults-release Python-modules-list googlebenchmark bz2 UUID double-conversion json-c MPFR O2-customization pytorch_cpuinfo safe_int FairCMakeModules Alice-GRID-Utils ninja ninja-fortran CMake date alibuild-recipe-tools'
+ echo 'FULL_BUILD_REQUIRES=defaults-release Python-modules-list googlebenchmark bz2 UUID double-conversion json-c MPFR O2-customization pytorch_cpuinfo safe_int FairCMakeModules Alice-GRID-Utils ninja ninja-fortran CMake date alibuild-recipe-tools'
FULL_BUILD_REQUIRES=defaults-release Python-modules-list googlebenchmark bz2 UUID double-conversion json-c MPFR O2-customization pytorch_cpuinfo safe_int FairCMakeModules Alice-GRID-Utils ninja ninja-fortran CMake date alibuild-recipe-tools
++ cut -f1 -d=
++ env
++ grep -v '^DEFAULT_'
++ grep -v PKGREVISION
++ grep REVISION
++ sed -e s/_REVISION//
++ grep -v ALIBUILD_RECIPE_TOOLS
+ for x in $(env | cut -f1 -d= | grep -v "^DEFAULT_" | grep -v PKGREVISION | grep -v ALIBUILD_RECIPE_TOOLS | grep REVISION | sed -e 's/_REVISION//')
++ eval 'echo $LIBFFI_REVISION'
+++ echo 10
+ REVISION_VALUE=10
++ eval 'echo $LIBFFI_VERSION'
+++ echo v3.2.1-alice1
+ VERSION_VALUE=v3.2.1-alice1
++ eval 'echo $LIBFFI_ROOT'
+++ echo /sw/slc9_x86-64/libffi/v3.2.1-alice1-10
+ ROOT_PATH_VALUE=/sw/slc9_x86-64/libffi/v3.2.1-alice1-10
+ '[' -z 10 ']'
+ echo 'defaults-release Python-modules-list googlebenchmark bz2 UUID double-conversion json-c MPFR O2-customization pytorch_cpuinfo safe_int FairCMakeModules Alice-GRID-Utils ninja ninja-fortran CMake date alibuild-recipe-tools'
+ tr '[:lower:]' '[:upper:]'
+ tr - _
[0 more errors; see full log]

Full log here.