v4.2.0 Released

[LeStarch]

This is F Prime v4.2.0!

1. Highlighted New Features
2. Changes Affecting Users
3. Changes Affecting Platform Developers

Highlighted New Features

These are the key features released in v4.2.0.

Advanced Telemetry Management

Svc::TlmPacketizer has been significantly enhanced to give projects fine-grained control over how telemetry is managed and downlinked.

Configurable output streams: Telemetry can now be routed to multiple configurable named sections (e.g. REALTIME for live downlink, RECORDED for store-and-forward). Each section is independently configurable and can be enabled or disabled at runtime.

Per-group rate control: Each section/group pair now has its own rate logic. Telemetry packets can be sent on-change with a configurable minimum tick interval (rate limiting), at a guaranteed maximum tick interval (heartbeat), or both. This replaces the previous all-or-nothing output on changemodel.

Configurable output port mapping: A 2D configuration table maps each section/group pair to a specific output port index, enabling flexible routing of telemetry streams to different downstream consumers.

All rate and stream settings are backed by a parameter, so defaults can be set at build time and overridden at runtime without a reboot.

To pair with this, Svc::ComQueuehas been extended with richer per-queue configuration:

Drop policy: Each queue can be configured to drop the newest (incoming) or oldest (head-of-queue) message on overflow, allowing projects to tune for freshness vs. in-order delivery. Queues can operate in FIFO or LIFO mode per-port. Per-queue priority controls which data is serviced first; queues sharing a priority are balanced via round-robin.

Topology Ports (Modeling)

FPP now supports topology ports — named I/O ports declared directly on a topology (subtopology). This allows a subtopology to be treated as a black-box module with well-defined connection points.

Outer topologies connect to a subtopology through its named ports without needing to reference internal component instances, improving encapsulation and reusability. All F Prime core subtopologies (Svc.CdhCore, Svc.ComCcsds, Svc.ComFprime, Svc.DataProducts, Svc.FileHandling) have been updated to expose topology ports.

New Component: Svc::FileWorker

Svc::FileWorker is a new active component that offloads slow file I/O operations from time-critical components. It provides asynchronous interfaces for reading, writing, and CRC-verifying files, with cancel support and state-based flow control (IDLE → READING/WRITING). Components that previously had to block on filesystem operations can now delegate to FileWorker and receive a completion signal when the operation is done.

Changes Affecting Users

These two changes affect users of F Prime.

1. Configuration Updates For Svc::TlmPacketizer

Svc::TlmPacketizer has been changed to allow for greater control over packet output rates. It now allows users to configure output groups, and sections to produce telemetry at specified rates. These changes are documented in the Svc::TlmPacketizer SDD.

Users with custom configuration for Svc::TlmPacketizer must update their configuration.

Build Configuration

Users including the TlmPacketizer autocoding (e.g. by including an FPP Packet Set in their topology) without using the TlmPacketizer itself now need to explicitly depend on the Config module in their Deployment/Top/CMakeLists.txt like such:

register_fprime_module(
  AUTOCODER_INPUTS
    "${CMAKE_CURRENT_LIST_DIR}/instances.fpp"
    "${CMAKE_CURRENT_LIST_DIR}/topology.fpp"
  SOURCES
    "${CMAKE_CURRENT_LIST_DIR}/RefTopology.cpp"
  DEPENDS
+    Svc_TlmPacketizer_config_TlmPacketizerConfig # Supports packet autocoding w/o TlmPacketizer  
)

Svc::TlmPacketizer Users With Custom Configuration

Users with custom configuration must make the following changes:

1. TLMPACKETIZER_HASH_BUCKETS must be renamed to MAX_PACKETIZER_CHANNELS.
2. TLMPACKETIZER_NUM_TLM_HASH_SLOTS, TLMPACKETIZER_HASH_MOD_VALUE, PacketUpdateMode must be deleted.
3. (Optional) Tune TlmPacketizerCfg.fpp to size output ports, sections, max groups, etc.

See TlmPacketizerCfg.hpp

Caution

The maximum group for a telemetry packet is now limited to NUM_CONFIGURABLE_TLMPACKETIZER_GROUPS found in TlmPacketizerCfg.fpp

Note

The stock TlmPacketizerCfg.fpp is designed to work with an output port for each of two sections. If left unconnected, the behavior will mimic Svc::TlmPacketizer of v4.2.0.
See TlmPacketizerCfg.hpp

2. Update Utils::Hash::final() to Utils::Hash::finalize()

In order to deconflict with the C++ final keyword, Utils::Hash::final() was renamed to Utils::Hash::finalize().

Utils::Hash Users

Users must rename their uses of the .final method.

- hash.final(crc_output);
+ hash.finalize(crc_output);

Changes Affecting Platform Developers

These changes affect developers providing platform packages in the F Prime environment.

Add teardown to Os::Queue

Since Os::Queue is allowed to allocate resources on a call to create, a mirror teardown method is needed to allow teardown.

For Platform Developers

At minimum, developers of Os::Queue implementations must define a teardown function.

+ void MyQueue ::teardown() {
+     ...
+ }

Use const Fw::TimeInterval& interval as Argument to Os::TaskInterface::_delay()

Os::TaskInterface uses a const Reference for the interval to prevent a copy when passing by value.

For Platform Developers

Implementers of Os::Task must switch to taking const TimeInterval& interval as input on their implementation of _delay.

- Os::Task::Status PosixTask::_delay(Fw::TimeInterval interval) {
+ Os::Task::Status PosixTask::_delay(const Fw::TimeInterval& interval) {

sscanf Implementation

F Prime now provides an sscanf implementation selection (like was previously available for printf). This was done to allow users to entirely bypass the format-function in the C library by providing their own implementations.

For Platform Developers

Platform developers, at minimum, should add a new implementation selection to their platform CMake.

      CHOOSES_IMPLEMENTATIONS
          ...
+         Fw_StringScan_sscanf

What's Changed

• Uplink file announce by @timcanham in Uplink file announce #4529
• Remove virtual methods from final classes by @Kronos3 in Remove virtual methods from final classes #4544
• Specify aggregator's priority by @kevin-f-ortega in Specify aggregator's priority #4545
• Prevent divide-by-zero in PosixFileSystem::_getFreeSpace by @heathdutton in Prevent divide-by-zero in PosixFileSystem::_getFreeSpace #4548
• Add missing status for invalid priority by @kevin-f-ortega in Add missing status for invalid priority #4541
• Remove Timeout from Svc::FileDownlink by @LeStarch in Remove Timeout from Svc::FileDownlink #4555
• Fix minor typos found during familiarization by @djbyrne17 in Fix minor typos found during familiarization #4556
• Remove fprime-system-reference from CI by @thomas-bc in Remove fprime-system-reference from CI #4558
• Update ground-interface.md and purge old FramingProtocol by @thomas-bc in Update ground-interface.md and purge old FramingProtocol #4547
• Add queue flush commands to com queue by @LeStarch in Add queue flush commands to com queue #4559
• Enclose macros iss4375 by @djbyrne17 in Enclose macros iss4375 #4568
• Fix/missing priority by @LeStarch in Fix/missing priority #4570
• Fix object slicing and modernize types in Version.cpp by @JuanPS999 in Fix object slicing and modernize types in Version.cpp #4563
• Fix formatting of data-products.md for website by @thomas-bc in Fix formatting of data-products.md for website #4571
• Prevent infinite loop in FileTest unique filename generation by @heathdutton in Prevent infinite loop in FileTest unique filename generation #4566
• Make timevalue and timeintervalvalue dict types by @zimri-leisher in Make timevalue and timeintervalvalue dict types #4575
• Switch to FPP enum for time comparisons by @zimri-leisher in Switch to FPP enum for time comparisons #4561
• Add Drv.AsyncByteStreamBufferAdapter (async) by @mshahabn in Add Drv.AsyncByteStreamBufferAdapter (async) #4557
• FpySequencer add function calling directives by @zimri-leisher in FpySequencer add function calling directives #4534
• Add Drv.ByteStreamBufferAdapter (sync) by @mshahabn in Add Drv.ByteStreamBufferAdapter (sync) #4546
• Document Memory Management patterns by @thomas-bc in Document Memory Management patterns #4507
• Fix/weak strong by @LeStarch in Fix/weak strong #4579
• DataProduct Catalog Runtime Insertion by @Willmac16 in DataProduct Catalog Runtime Insertion #4083
• Fix DpCatalog UT Memory Leak by @LeStarch in Fix DpCatalog UT Memory Leak #4589
• Enclose macros by @djbyrne17 in Enclose macros #4582
• Correct TmFramer size assertion math by @Willmac16 in Correct TmFramer size assertion math #4592
• Telemeter params on startup for FpySeq by @Willmac16 in Telemeter params on startup for FpySeq #4603
• Clear invalid context in ComAggregator doClear action by @heathdutton in Clear invalid context in ComAggregator doClear action #4597
• Use FPP constant for FileDownlink filename length by @heathdutton in Use FPP constant for FileDownlink filename length #4594
• Enhance TDD guide with detailed explanations and tips by @LeStarch in Enhance TDD guide with detailed explanations and tips #4583
• Add new Svc::ComRetry component by @valdaarhun in Add new Svc::ComRetry component #4367
• Add Svc.FileDispatcher component by @timcanham in Add Svc.FileDispatcher component #4552
• Add File Dispatcher port to CmdSequencer by @timcanham in Add File Dispatcher port to CmdSequencer #4553
• Fix student review feedback for ROSES - Data Processing Plugins - Student Review #4101 by @LeStarch in Fix student review feedback for #4101 #4584
• Update GDS App Plugin documentation by @LeStarch in Update GDS App Plugin documentation #4585
• Bump werkzeug from 3.1.4 to 3.1.5 by @dependabot[bot] in Bump werkzeug from 3.1.4 to 3.1.5 #4608
• Bump urllib3 from 2.6.0 to 2.6.3 by @dependabot[bot] in Bump urllib3 from 2.6.0 to 2.6.3 #4607
• Calculate Data Product checksum in the DpWriter component by @kubiak-jpl in Calculate Data Product checksum in the DpWriter component #4622
• Fix invalid start parameter in gds-test-api-guide examples by @heathdutton in Fix invalid start parameter in gds-test-api-guide examples #4639
• Add dict specifier to FpySequencer consts by @zimri-leisher in Add dict specifier to FpySequencer consts #4638
• Suppress duplicate library warning on macos by @Willmac16 in Suppress duplicate library warning on macos #4628
• Update dictionary spec to require FW_FIXED_LENGTH_STRING_SIZE by @jwest115 in Update dictionary spec to require FW_FIXED_LENGTH_STRING_SIZE #4667
• Add data product how-to by @LeStarch in Add data product how-to #4664
• Update Data Products integration tests and bump fprime-gds by @thomas-bc in Update Data Products integration tests and bump fprime-gds #4671
• Expose default file create permissions through a new OsCfg.fpp config file by @kubiak-jpl in Expose default file create permissions through a new OsCfg.fpp config file #4613
• Address workshop feedback for data products How-To by @thomas-bc in Address workshop feedback for data products How-To #4682
• Add CRC checks to Svc.PrmDb by @odacindy-fprime in Add CRC checks to Svc.PrmDb #4586
• Update requirements.txt to work with Python 3.14 by @thomas-bc in Update requirements.txt to work with Python 3.14 #4616
• Fix static analysis issues in Serializable.cpp by @Sarah5567 in Fix static analysis issues in Serializable.cpp #4634
• Correct isConnected check in FpySequencer for seqStartOut by @Willmac16 in Correct isConnected check in FpySequencer for seqStartOut #4647
• Fix PolyType Static Analysis Issues by @youio in Fix PolyType Static Analysis Issues #4649
• Initialize variables to fix static analysis warnings by @Jashan66 in Initialize variables to fix static analysis warnings #4672
• Add methods to convert from Fw::Time* to Fw::Time*Value by @LeStarch in Add methods to convert from Fw::Time* to Fw::Time*Value #4658
• Updated default file creation mode to a+rw equivalent by @kubiak-jpl in Updated default file creation mode to a+rw equivalent #4679
• Update hello-world namespaces in CI by @thomas-bc in Update hello-world namespaces in CI #4692
• Revise FppTest by @bocchino in Revise FppTest #4659
• Revise modeling and code gen for default string sizes by @bocchino in Revise modeling and code gen for default string sizes #4673
• Add Fw.DataProduct FPP interface by @thomas-bc in Add Fw.DataProduct FPP interface #4669
• Add baremetal and multi-core documentation by @thomas-bc in Add baremetal and multi-core documentation #4680
• Update README with team roles and maintainers by @LeStarch in Update README with team roles and maintainers #4722
• FpySequencer push FW_SERIALIZE_TRUE/FALSE for boolean ops by @zimri-leisher in FpySequencer push FW_SERIALIZE_TRUE/FALSE for boolean ops #4712
• Update governance roles and privileges by @LeStarch in Update governance roles and privileges #4718
• Add verification steps for system requirements by @djbyrne17 in Add verification steps for system requirements #4710
• Add kevin-f-ortega as Community Manager by @LeStarch in Add kevin-f-ortega as Community Manager #4725
• Fix markdown formatting across documentation by @thomas-bc in Fix markdown formatting across documentation #4709
• Update vulnerability reporting instructions by @LeStarch in Update vulnerability reporting instructions #4736
• Implement Os::Queue::setRegistry by @jsmith212 in Implement Os::Queue::setRegistry #4648
• Os static analysis findings by @Sarah5567 in Os static analysis findings #4665
• Replace global assert hook with static class member by @Gregox273 in Replace global assert hook with static class member #4701
• Clean up DpCatalog test artifacts in destructor by @heathdutton in Clean up DpCatalog test artifacts in destructor #4714
• ComQueue queue ordering, drop mode, & command to reprioritize by @Willmac16 in ComQueue queue ordering, drop mode, & command to reprioritize #4674
• Fix: Clean up generated files in ComLoggerTester by @Sarah5567 in Fix: Clean up generated files in ComLoggerTester #4735
• Fixed broken CCSDS links by @Brian-Campuzano in Fixed broken CCSDS links #4743
• Fix FILE_NAME_ARG definition by @thomas-bc in Fix FILE_NAME_ARG definition #4754
• Increase FpySequencer UT coverage to 87% by @zimri-leisher in Increase FpySequencer UT coverage to 87% #4747
• TlmPacketizer Group Level Control Improvements by @Lex-ari in TlmPacketizer Group Level Control Improvements #4668
• Add checks to TC deframing stack to prevent underflows by @thomas-bc in Add checks to TC deframing stack to prevent underflows #4763
• Add How-To Implement a Radio Manager by @thomas-bc in Add How-To Implement a Radio Manager #4738
• S_ISVTX is part of XSI, which is an optional set of interfaces and ex… by @kevin-f-ortega in S_ISVTX is part of XSI, which is an optional set of interfaces and ex… #4768
• Add configure section/group port to TlmPacketizer by @LeStarch in Add configure section/group port to TlmPacketizer #4766
• Modify Os::Task::delay to pass in interval by const reference by @Gregox273 in Modify Os::Task::delay to pass in interval by const reference #4751
• Use GH Actions inputs through environment variables by @thomas-bc in Use GH Actions inputs through environment variables #4764
• Bump werkzeug from 3.1.5 to 3.1.6 by @dependabot[bot] in Bump werkzeug from 3.1.5 to 3.1.6 #4778
• Bump flask from 3.0.3 to 3.1.3 by @dependabot[bot] in Bump flask from 3.0.3 to 3.1.3 #4777
• Add CCSDS AOS Framer by @Willmac16 in Add CCSDS AOS Framer #4630
• Topology connection unit tests by @Kronos3 in Topology connection unit tests #4765
• Modify circular buffer overflow test to handle zero-length random input by @Gregox273 in Modify circular buffer overflow test to handle zero-length random input #4752
• Use FPP enum for state machine state by @bocchino in Use FPP enum for state machine state #4803
• Add required fixes for F Prime to have deinit triggered by autocode by @LeStarch in Add required fixes for F Prime to have deinit triggered by autocode #4800
• Warn on zero-size downlink. Fixes: Attempting to Downlink Zero-Length File Results in Poor Warning #2756 by @LeStarch in Warn on zero-size downlink. Fixes: #2756 #4802
• Remove doOtherChecks from health. Fixes: Fix Health Clang-Tidy Issue #4404 by @LeStarch in Remove doOtherChecks from health. Fixes: #4404 #4801
• Add README explaining tutorial directory structure by @ryanhasmanners in Add README explaining tutorial directory structure #4812
• Resolve Utils/Hash static analysis findings by @vsoulgard in Resolve Utils/Hash static analysis findings #4799
• Topology Ports in FPP by @Kronos3 in Topology Ports in FPP #4805
• Fixed corner case in shadow write when writing 0 bytes in append mode by @kevin-f-ortega in Fixed corner case in shadow write when writing 0 bytes in append mode #4821
• FpySequencer use FwTimeBaseStoreType instead of U16 by @zimri-leisher in FpySequencer use FwTimeBaseStoreType instead of U16 #4820
• Allow bypassing ignore list by @LeStarch in Allow bypassing ignore list #4771
• Add System Functional Documentation - Dictionary by @swanchr in Add System Functional Documentation - Dictionary #4780
• Fix static analysis warning in Posix ConditionVariable.cpp by @thomas-bc in Fix static analysis warning in Posix ConditionVariable.cpp #4814
• Fix RawTime serializability concerns by @thomas-bc in Fix RawTime serializability concerns #4811
• Fix String type in FileDownlink by @vsoulgard in Fix String type in FileDownlink #4823
• Update dictionary spec value description by @jwest115 in Update dictionary spec value description #4827
• Update License by @Lex-ari in Update License #4828
• Remove priority from ActiveTextLogger by @timcanham in Remove priority from ActiveTextLogger #4798
• Use Java FPP for fpp-to-json by @Kronos3 in Use Java FPP for fpp-to-json #4829
• Bump markdown from 3.7 to 3.8.1 by @dependabot[bot] in Bump markdown from 3.7 to 3.8.1 #4832
• Data product async interface by @Sarah5567 in Data product async interface #4727
• Add deinit function for passive components by @LeStarch in Add deinit function for passive components #4831
• Refactor Ccsds.ApidManager to use Fw::ArrayMap by @vsoulgard in Refactor Ccsds.ApidManager to use Fw::ArrayMap #4833
• Make Os::QueueInterface::teardown() pure virtual by @vsoulgard in Make Os::QueueInterface::teardown() pure virtual #4824
• Fix CI from discarding errors in UTs by @LeStarch in Fix CI from discarding errors in UTs #4853
• Fix CI scripts FPUTIL_TARGETS by @thomas-bc in Fix CI scripts FPUTIL_TARGETS #4856
• Fix to operator= for ExternalSerializeBufferWithMemberCopy by @bocchino in Fix to operator= for ExternalSerializeBufferWithMemberCopy #4855
• Clarify instructions that caused problems for new users by @djbyrne17 in Clarify instructions that caused problems for new users #4849
• Issue 4790 generic hub command ports by @mshahabn in Issue 4790 generic hub command ports #4793
• Add System Functional Documentation - Sequencing by @swanchr in Add System Functional Documentation - Sequencing #4781
• Add OS Abstraction Layer SDD and How-To guide by @thomas-bc in Add OS Abstraction Layer SDD and How-To guide #4840
• Add PassThroughRouter component by @DJKessler in Add PassThroughRouter component #4825
• TlmPacketizer: Remove Double-Buffering by @Sarah5567 in TlmPacketizer: Remove Double-Buffering #4822
• Add floating point operations for Fw::Time by @vsoulgard in Add floating point operations for Fw::Time #4842
• Add PR auto-reply when Formatting CI fails by @Copilot in Add PR auto-reply when Formatting CI fails #4870
• Switching inline hash map and slots with r/b tree by @LeStarch in Switching inline hash map and slots with r/b tree #4871
• FileWorker by @rjtsao in FileWorker #4810
• Refactor PrmDb to use Fw::ArrayMap by @Kronos3 in Refactor PrmDb to use Fw::ArrayMap #4881
• Replace cmd dispatch table with map by @LeStarch in Replace cmd dispatch table with map #4883
• Update fprime-fpl-layout and fprime-fpl-write-pic versions to 1.0.4 by @LeStarch in Update fprime-fpl-layout and fprime-fpl-write-pic versions to 1.0.4 #4886
• Fix TlmPacketizer large entry copy by @LeStarch in Fix TlmPacketizer large entry copy #4878
• Remove test output files for FileWorker by @bocchino in Remove test output files for FileWorker #4895
• Remove erroneous include in PassThroughRouterTester by @thomas-bc in Remove erroneous include in PassThroughRouterTester #4901
• Update FpConstants to use sizeof, add sizeof tests to FppTest by @jwest115 in Update FpConstants to use sizeof, add sizeof tests to FppTest #4859
• Fix PosixFile UT random failures by @LeStarch in Fix PosixFile UT random failures #4905
• Add FppTest tests for empty structs by @bocchino in Add FppTest tests for empty structs #4908
• Adding sscanf replacement implementation, and tests by @LeStarch in Adding sscanf replacement implementation, and tests #4872
• Replace command sequence table with map by @LeStarch in Replace command sequence table with map #4888
• FPP Framework Testing by @Kronos3 in FPP Framework Testing #4890
• Add in function to dispatch all available messages by @LeStarch in Add in function to dispatch all available messages #4911
• FPP v3.2.0 by @bocchino in FPP v3.2.0 #4912
• Add option to force assertions to always abort by @celskeggs in Add option to force assertions to always abort #4677
• Bump pygments from 2.18.0 to 2.20.0 by @dependabot[bot] in Bump pygments from 2.18.0 to 2.20.0 #4916
• Add topology ports to subtopologies by @Sarah5567 in Add topology ports to subtopologies #4907
• Improve data copying efficiency in TlmPacketizer by @Sarah5567 in Improve data copying efficiency in TlmPacketizer #4868
• Update MmapAllocator by @kubiak-jpl in Update MmapAllocator #4892
• refactor: replace FW_MIN/FW_MAX macros with std::min/std::max by @dcpagotto in refactor: replace FW_MIN/FW_MAX macros with std::min/std::max #4865
• docs: fix double word and formatting in introduction by @aliden1z in docs: fix double word and formatting in introduction #4924
• Omega by @LeStarch in Omega #4919
• Making TlmPacketizer configuration tables driven from parameter by @LeStarch in Making TlmPacketizer configuration tables driven from parameter #4830
• Remove legacy Cheetah3 dependency by @thomas-bc in Remove legacy Cheetah3 dependency #4927
• Update fprime-gds and fprime-tools versions for v4.2.0 by @LeStarch in Update fprime-gds and fprime-tools versions for v4.2.0 #4930
• Fix hard-asserts in GenericHub deserialization by @LeStarch in Fix hard-asserts in GenericHub deserialization #4929
• Add an agent that reviews standard norms for F Prime by @LeStarch in Add an agent that reviews standard norms for F Prime #4935
• Update PR review instructions for agent availability by @LeStarch in Update PR review instructions for agent availability #4937
• Remove non-functional PR comment workflow by @thomas-bc in Remove non-functional PR comment workflow #4933

New Contributors

• @heathdutton made their first contribution in Prevent divide-by-zero in PosixFileSystem::_getFreeSpace #4548
• @JuanPS999 made their first contribution in Fix object slicing and modernize types in Version.cpp #4563
• @odacindy-fprime made their first contribution in Add CRC checks to Svc.PrmDb #4586
• @Sarah5567 made their first contribution in Fix static analysis issues in Serializable.cpp #4634
• @youio made their first contribution in Fix PolyType Static Analysis Issues #4649
• @Jashan66 made their first contribution in Initialize variables to fix static analysis warnings #4672
• @jsmith212 made their first contribution in Implement Os::Queue::setRegistry #4648
• @Gregox273 made their first contribution in Replace global assert hook with static class member #4701
• @ryanhasmanners made their first contribution in Add README explaining tutorial directory structure #4812
• @vsoulgard made their first contribution in Resolve Utils/Hash static analysis findings #4799
• @swanchr made their first contribution in Add System Functional Documentation - Dictionary #4780
• @rjtsao made their first contribution in FileWorker #4810
• @dcpagotto made their first contribution in refactor: replace FW_MIN/FW_MAX macros with std::min/std::max #4865
• @aliden1z made their first contribution in docs: fix double word and formatting in introduction #4924

Full Changelog: v4.1.1...v4.2.0

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This discussion was created from the release v4.2.0: Advanced Telemetry Management.