feat: create the logger, wired to nothing, and watch it say so

[DavidCozens]

Pull request

What this stage adds

The logger is created with both collaborators absent, deliberately. Create never
fails and never returns NULL — a missing collaborator is substituted with its
Null object — so the only evidence is what the handler prints, and the run report
now carries three of them:

[syslog] CRITICAL SolidSyslog bad-config (detail 1)
[syslog] CRITICAL SolidSyslog bad-config (detail 2)
[syslog] CRITICAL SolidSyslog bad-config (detail 3)

Flash +1,036 B
RAM +180 B

Doing it in this order is the point. An integrator who wires everything at once
and sees nothing cannot tell a working logger from a silent one; seeing the
faults first, and then watching them go quiet as collaborators arrive, is the
difference between believing it works and knowing.

NULL is "not supplied" and is reported. A collaborator deliberately done without
is passed as its Null object instead — the library tells those two apart, and so
should anyone reading this wiring later.

Files

 CMakeLists.txt          |  1 +
 README.md               | 11 ++++++-----
 app/main.c              |  3 +++
 app/syslog/Syslog.c     | 30 ++++++++++++++++++++++++++++++
 app/syslog/Syslog.h     | 15 +++++++++++++++
 measurements/logger.csv | 13 +++++++++++++
 measurements/stages.tsv |  1 +
 run-report.md           | 31 +++++++++++++++++--------------
 8 files changed, 86 insertions(+), 19 deletions(-)

Checklist

• The diff touches build infra (1 file(s)) — see Files above; deliberate for this stage.
• measurements/logger.csv committed.
• Row added to measurements/stages.tsv.
• README regenerated: python3 scripts/gen-cost-table.py.
• ./run.sh green (build + QEMU + baseline self-check) — run-report.md committed.

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Context for review: 3 of 21 sequential single-commit PRs replaying the integration on top of the Baseline root. Each lands green and reviewed before the next is built on it, because a change to an early commit would force every commit above it to be re-run and re-measured.

Summary by CodeRabbit

• New Features

  • Added application-level syslog initialization during startup.
  • Added access to the shared logger for application tasks.

• Documentation

  • Updated stage descriptions and resource-cost figures to reflect logger creation.
  • Refreshed run reports, memory measurements, and self-check results for the logger configuration.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: be39c956-4a05-4d5f-a264-28ca3c381c54

📥 Commits

Reviewing files that changed from the base of the PR and between c2c95ea and 1226a34.

⛔ Files ignored due to path filters (2)

• measurements/logger.csv is excluded by !**/*.csv
• measurements/stages.tsv is excluded by !**/*.tsv

📒 Files selected for processing (6)

• CMakeLists.txt
• README.md
• app/main.c
• app/syslog/Syslog.c
• app/syslog/Syslog.h
• run-report.md

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📝 Walkthrough

Walkthrough

The application adds a syslog wrapper that creates an empty SolidSyslog instance, compiles it into the baseline executable, starts it during initialization, and documents updated logger-stage measurements.

Changes

Logger creation wiring

Layer / File(s)	Summary
Syslog API and empty instance creation app/syslog/Syslog.h, app/syslog/Syslog.c	Defines the opaque logger API, creates SolidSyslog with null buffer and sender collaborators, and exposes its shared handle.
Build and startup integration CMakeLists.txt, app/main.c	Adds Syslog.c to the baseline executable and calls Syslog_Start() after installing the error handler.
Stage documentation and run measurements README.md, run-report.md	Renames the documented stage to “Logger created” and updates cost, size, scenario, and self-check values.

Estimated code review effort: 2 (Simple) | ~10 minutes

Sequence Diagram(s)

sequenceDiagram
  participant main
  participant Syslog
  participant SolidSyslog
  main->>Syslog: Syslog_Start()
  Syslog->>SolidSyslog: SolidSyslog_Create(config)
  SolidSyslog-->>Syslog: shared logger instance

Loading

Possibly related PRs

• cososo-ltd/solid-syslog-example#10: Overlaps with the SolidSyslog wrapper API and startup wiring.
• cososo-ltd/solid-syslog-example#29: Adds the error-handler installation that precedes Syslog_Start().
• cososo-ltd/solid-syslog-example#28: Provides earlier SolidSyslog build and linking integration used by this wrapper.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main change: creating the logger with no collaborators wired in.
Description check	✅ Passed	The description matches the template structure and includes the required stage summary and checklist items.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch stage/logger

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