fix: treat IPv4LL DHCP assignments as incomplete during boot

[ljm42]

Summary

• Treat IPv4LL/link-local DHCP assignments as incomplete during boot.
• When IPv4 DHCP is enabled and the interface has carrier, rc.inet1 now waits up to 60 seconds for a non-link-local IPv4 address instead of continuing as soon as dhcpcd assigns a 169.254.x.x address.
• Clarify DHCP fallback logs to distinguish an existing dhcpcd process from starting a new background process.

Validation

• Ran: bash -n etc/rc.d/rc.inet1
• Tested on test4 with the updated rc.inet1 override. During boot, dhcpcd assigned 169.254.150.83 at 14:25:51, then rc.inet1 continued waiting until dhcpcd leased 10.11.1.191 at 14:25:59.
• Confirmed current test4 state: br0 has 10.11.1.191/24, default route via 10.11.1.1, and nameserver 10.11.1.1.

Summary by CodeRabbit

• Bug Fixes

  • Improved DHCP handling to avoid unnecessary restarts when DHCP is already running and to better detect link-local-only IPv4 addresses.
  • Clarified log messages during interface bring-up/shutdown for more accurate diagnostics.

• New Features

  • Added IPv4-specific DHCP wait and address detection to reduce false negatives during interface initialization.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: 0a84323e-ee71-4240-8f57-ca3dec36ee17

📥 Commits

Reviewing files that changed from the base of the PR and between 5cf8a69 and 5880ba1.

📒 Files selected for processing (1)

• etc/rc.d/rc.inet1

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Walkthrough

Adds dhcp4_addr() and dhcp_wait() to detect non-link-local IPv4 addresses and wrap dhcpcd -w with a 60s timeout and IPv4 polling; ipaddr_up() now calls dhcp_wait() and branches on its return to log IPv4LL-only, do nothing, or start dhcpcd in background.

Changes

DHCP Polling Enhancement

Layer / File(s)	Summary
DHCP polling helper functions etc/rc.d/rc.inet1	Adds dhcp4_addr() to detect non-169.254.x.x IPv4 addresses and dhcp_wait() to run dhcpcd -w with a 60s timeout and (for IPv4) poll to distinguish IPv4LL-only vs non-link-local assignment; returns status codes for callers.
DHCP startup flow integration etc/rc.d/rc.inet1	Refactors ipaddr_up() carrier-present path to call dhcp_wait() and branch on its return: 0 requires no action, 2 logs IPv4LL-only and leaves dhcpcd running, other failures start dhcpcd -b in background; updates carrier-down log wording.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

I nibble on code beneath the moon,
Two tiny helpers hum a tune,
One sniffs link-local in the air,
One waits a beat to be more fair,
Then ipaddr_up acts — light as a rune. 🐰

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: treating IPv4 Link-Local (169.254.x.x) DHCP assignments as incomplete during boot and waiting for a proper address.
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.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix-dhcp-ipv4ll-boot-wait

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[github-actions]

🔧 PR Test Plugin Available

A test plugin has been generated for this PR that includes the modified files.

Version: 2026.05.25.1631
Build: View Workflow Run

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📝 Modified Files:

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etc/rc.d/rc.inet1

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