recpart

Partition planning and apply backend for LevitateOS install flows.

Scope

recpart is responsible for partitioning, formatting, and mount orchestration only. It does not perform full OS installation.

Frontend

The canonical interactive TUI flow lives at tui/apps/install/disk-plan, built on tui/kit/core and recpart backend JSON contracts.

Goals

• Provide a safe disk partition workflow for backend consumers.
• Support two layout modes:
  • ab (default): A/B immutable-ready partition layout.
  • mutable: classic mutable root layout.
• Preview exact commands/scripts before destructive actions.
• Fail fast with explicit diagnostics and remediation.

Non-Goals

• Slot switching or commit/rollback state machine.
• Integrity policy enforcement (dm-verity, signature verification, measured boot).
• Full install automation (rootfs extraction, chroot config, service enablement).

Planned UX

1. Select target disk.
2. Select layout mode (ab default, mutable).
3. Show partition plan and generated sfdisk script.
4. Explicit destructive confirmation.
5. Apply partition table.
6. Format filesystems and apply labels.
7. Mount targets under a predictable tree for downstream tools.
8. Print next commands (recstrap, recfstab, recchroot).

Planned Components

• plan module:
  • deterministic partition plan model
  • mode-specific templates
  • sfdisk script generation
• exec module:
  • command runner with structured logs
  • idempotent safety checks

Integration Contract

• Input: selected disk + mode + optional layout request values (policy defaults apply when omitted).
• Output: mounted target topology + machine-readable summary.
• Downstream tools:
  • recstrap
  • recfstab
  • recchroot
  • recab (A/B mode consumers)

Exit Codes

Code	Meaning
1 (E001)	Invalid target disk / target safety failure
2 (E002)	Required tool missing
3 (E003)	Plan generation or policy validation failure
4 (E004)	Missing destructive confirmation
5 (E005)	Partition apply failure
6 (E006)	Filesystem format failure
7 (E007)	Mount validation or mount execution failure
8 (E008)	Handoff generation failure
9 (E009)	JSON serialization failure
10 (E010)	Reserved not-implemented code
11 (E011)	Root privileges required
12 (E012)	Internal/runtime error