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apply mode: wire partition apply + mkfs; btrfs RAID1 flags and -f; UEFI detection and skip bios_boot when UEFI; sgdisk-based partition apply; update TODO and REGION markers

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This commit is contained in:
Jan De Landtsheer
2025-09-29 15:10:57 +02:00
parent b0e41b59b1
commit 04216b7f8f
7 changed files with 295 additions and 43 deletions
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34
TODO.md
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@@ -9,18 +9,30 @@ Conventions:
Core execution
- [ ] Add “apply mode” switch to orchestrator to perform destructive actions after preview validation
- Wire phase execution in [orchestrator.run(&Context)](src/orchestrator/run.rs:101): apply partitions → udev settle → mkfs → mount → maybe write fstab → build/write report
- Introduce a CLI flag (e.g. `--apply`) guarded by clear logs and safety checks (not preview)
- [ ] Partition application (destructive) in [fn apply_partitions(...)](src/partition/plan.rs:287)
- Translate [PartitionPlan](src/partition/plan.rs:80) to sgdisk commands (create GPT, partitions in order with alignment and names)
- Enforce idempotency: skip if table already matches plan (or abort with explicit validation error)
- Ensure unique partition GUIDs; capture partition device paths and GUIDs for results
- Call [util::udev_settle()](src/util/mod.rs:128) after changes; robust error mapping to Error::Tool / Error::Partition
- [-] Add “apply mode” switch to orchestrator to perform destructive actions after preview validation
- [x] Introduce CLI flag --apply guarded by clear logs and safety checks (not preview) [src/cli/args.rs](src/cli/args.rs)
- [x] Wire partition application and udev settle [orchestrator::run()](src/orchestrator/run.rs:1) → [partition::apply_partitions()](src/partition/plan.rs:1)
- [-] Wire mkfs → mount → maybe write fstab → build/write report [src/orchestrator/run.rs](src/orchestrator/run.rs)
- [x] Wire mkfs: plan_filesystems + make_filesystems [src/orchestrator/run.rs](src/orchestrator/run.rs) + [src/fs/plan.rs](src/fs/plan.rs)
- [ ] Wire mounts (plan/apply) [src/mount/ops.rs](src/mount/ops.rs)
- [ ] maybe write fstab [src/mount/ops.rs](src/mount/ops.rs)
- [ ] build/write report [src/report/state.rs](src/report/state.rs)
- [x] Partition application (destructive) in [partition::apply_partitions()](src/partition/plan.rs:1)
- [x] Boot mode detection and BIOS boot policy
- [x] Implement UEFI detection via /sys/firmware/efi: [is_efi_boot()](src/util/mod.rs:151)
- [x] Planner skips BIOS boot partition when UEFI-booted: [partition::plan_partitions()](src/partition/plan.rs:133)
- [ ] Future: revisit bootblock/bootloader specifics for BIOS vs EFI (confirm if any BIOS-targets require bios_boot) [docs/ARCHITECTURE.md](docs/ARCHITECTURE.md)
- [x] Translate [PartitionPlan](src/partition/plan.rs:1) to sgdisk commands (create GPT, partitions in order with alignment and names)
- [x] Enforce idempotency when required via [idempotency::is_empty_disk()](src/idempotency/mod.rs:1); abort on non-empty
- [x] Capture partition GUIDs, names, device paths via sgdisk -i parsing; map to PartitionResult
- [x] Call [util::udev_settle()](src/util/mod.rs:1) after changes; consistent Error::Tool/Error::Partition mapping
- [-] Filesystem creation in [fn make_filesystems(...)](src/fs/plan.rs:182)
- [x] Base mkfs implemented for vfat/btrfs/bcachefs (UUID capture via blkid)
- [ ] Apply btrfs raid profile from config (e.g., `-m raid1 -d raid1`) for [Topology::BtrfsRaid1](src/types.rs:29) and the desired profile in [struct BtrfsOptions](src/types.rs:89)
- [ ] Optionally map compression options for btrfs and bcachefs from config (e.g., `-O compress=zstd:3` or format-equivalent)
- [x] Apply btrfs RAID profile when topology requires it (multi-device): pass -m raid1 -d raid1 in mkfs.btrfs [src/fs/plan.rs](src/fs/plan.rs)
- [x] Force mkfs.btrfs in apply path with -f to handle leftover signatures from partial runs [src/fs/plan.rs](src/fs/plan.rs)
- [ ] Compression/tuning mapping from config
- [ ] btrfs: apply compression as mount options during mounting phase [src/mount/ops.rs](src/mount/ops.rs)
- [ ] bcachefs: map compression/checksum/cache_mode to format flags (deferred) [src/fs/plan.rs](src/fs/plan.rs)
- [ ] Consider verifying UUID consistency across multi-device filesystems and improve error messages
- [ ] Mount planning and application in [mount::ops](src/mount/ops.rs:1)
- [ ] Implement [fn plan_mounts(...)](src/mount/ops.rs:68): map FsResult UUIDs into `/var/cache/{UUID}` using [cfg.mount.base_dir](src/types.rs:136), and synthesize options per FS kind
@@ -44,7 +56,7 @@ CLI, config, defaults
- [x] Built-in sensible defaults (no YAML required) [src/config/loader.rs](src/config/loader.rs:320)
- [x] Overlays from CLI: log level, file logging, fstab, removable policy, topology [src/config/loader.rs](src/config/loader.rs:247)
- [x] Preview flags (`--show`, `--report`) and topology selection (`-t/--topology`) [src/cli/args.rs](src/cli/args.rs:55)
- [ ] Add `--apply` flag to toggle execute mode and keep preview non-destructive by default [src/cli/args.rs](src/cli/args.rs:55)
- [x] Add `--apply` flag to toggle execute mode and keep preview non-destructive by default [src/cli/args.rs](src/cli/args.rs)
- [ ] Consider environment variable overlays [src/config/loader.rs](src/config/loader.rs:39)
- [ ] Consider hidden/dev flags behind features (e.g., `--dry-run-verbose`, `--trace-io`) [src/cli/args.rs](src/cli/args.rs:26)

4
src/cli/args.rs
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@@ -113,6 +113,10 @@ pub struct Cli {
/// Write detection/planning JSON report to the given path (overrides config.report.path)
#[arg(long = "report")]
pub report: Option<String>,
/// Execute destructive actions (apply mode). When false, runs preview-only.
#[arg(long = "apply", default_value_t = false)]
pub apply: bool,
}
/// Parse CLI arguments (non-interactive; suitable for initramfs).

38
src/fs/plan.rs
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@@ -18,20 +18,21 @@
// ext: dry-run mode to emit mkfs commands without executing (future).
// REGION: EXTENSION_POINTS-END
//
// REGION: SAFETY
// safety: must not run mkfs on non-empty or unexpected partitions; assume prior validation enforced.
// safety: ensure labels follow reserved semantics (ZOSBOOT for ESP, ZOSDATA for all data FS).
// REGION: SAFETY-END
// REGION: SAFETY
// safety: must not run mkfs on non-empty or unexpected partitions; assume prior validation enforced.
// safety: ensure labels follow reserved semantics (ZOSBOOT for ESP, ZOSDATA for all data FS).
// safety: mkfs.btrfs uses -f in apply path immediately after partitioning to handle leftover signatures.
// REGION: SAFETY-END
//
// REGION: ERROR_MAPPING
// errmap: external mkfs/blkid failures -> crate::Error::Tool with captured stderr.
// errmap: planning mismatches -> crate::Error::Filesystem with context.
// REGION: ERROR_MAPPING-END
//
// REGION: TODO
// todo: implement mapping of topology to FsSpec including bcachefs cache/backing composition.
// todo: implement mkfs invocation and UUID capture via util::run_cmd / util::run_cmd_capture.
// REGION: TODO-END
// REGION: TODO
// todo: bcachefs tuning flags mapping from config (compression/checksum/cache_mode) deferred
// todo: add UUID consistency checks across multi-device filesystems
// REGION: TODO-END
//! Filesystem planning and creation for zosstorage.
//!
//! Maps partition results to concrete filesystems (vfat, btrfs, bcachefs)
@@ -220,8 +221,25 @@ pub fn make_filesystems(plan: &FsPlan) -> Result<Vec<FsResult>> {
if spec.devices.is_empty() {
return Err(Error::Filesystem("btrfs requires at least one device".into()));
}
// mkfs.btrfs -L LABEL dev1 [dev2 ...]
// mkfs.btrfs -L LABEL [ -m raid1 -d raid1 (when multi-device/raid1) ] dev1 [dev2 ...]
let mut args: Vec<String> = vec![mkfs.clone(), "-L".into(), spec.label.clone()];
// If this Btrfs is multi-device (as planned in BtrfsRaid1 topology),
// set metadata/data profiles to raid1. This keeps plan/apply consistent.
if spec.devices.len() >= 2 {
args.push("-m".into());
args.push("raid1".into());
args.push("-d".into());
args.push("raid1".into());
}
// Note: compression is a mount-time option for btrfs; we will apply it in mount phase.
// Leaving mkfs-time compression unset by design.
// Force formatting in apply path to avoid leftover signatures on freshly created partitions.
// Safe because we just created these partitions in this run.
args.push("-f".into());
args.extend(spec.devices.iter().cloned());
let args_ref: Vec<&str> = args.iter().map(|s| s.as_str()).collect();
run_cmd(&args_ref)?;
@@ -244,6 +262,8 @@ pub fn make_filesystems(plan: &FsPlan) -> Result<Vec<FsResult>> {
return Err(Error::Filesystem("bcachefs requires at least two devices (cache + backing)".into()));
}
// bcachefs format --label LABEL dev_cache dev_backing ...
// TODO(fs): map compression/checksum/cache-mode flags from config in a follow-up.
// This is deferred per current scope to focus on btrfs RAID profile wiring.
let mut args: Vec<String> = vec![mkfs.clone(), "format".into(), "--label".into(), spec.label.clone()];
args.extend(spec.devices.iter().cloned());
let args_ref: Vec<&str> = args.iter().map(|s| s.as_str()).collect();

1
src/main.rs
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@@ -51,6 +51,7 @@ fn real_main() -> Result<()> {
let ctx = orchestrator::Context::new(cfg, log_opts)
.with_show(cli.show)
.with_apply(cli.apply)
.with_report_path(cli.report.clone());
orchestrator::run(&ctx)
}

38
src/orchestrator/run.rs
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@@ -48,6 +48,7 @@ use crate::{
device::{discover, DeviceFilter, Disk},
idempotency,
partition,
fs as zfs,
Error, Result,
};
use humantime::format_rfc3339;
@@ -66,6 +67,8 @@ pub struct Context {
pub log: LogOptions,
/// When true, print detection and planning summary to stdout (JSON).
pub show: bool,
/// When true, perform destructive actions (apply mode).
pub apply: bool,
/// Optional report path override (when provided by CLI --report).
pub report_path_override: Option<String>,
}
@@ -77,6 +80,7 @@ impl Context {
cfg,
log,
show: false,
apply: false,
report_path_override: None,
}
}
@@ -93,6 +97,16 @@ impl Context {
self
}
/// Enable or disable apply mode (destructive).
///
/// When set to true (e.g. via `--apply`), orchestrator:
/// - Enforces empty-disk policy (unless disabled in config)
/// - Applies partition plan, then (future) mkfs, mounts, and report
pub fn with_apply(mut self, apply: bool) -> Self {
self.apply = apply;
self
}
/// Override the report output path used by preview mode.
///
/// When provided (e.g. via `--report /path/file.json`), orchestrator:
@@ -171,11 +185,27 @@ pub fn run(ctx: &Context) -> Result<()> {
debug!("plan for {}: {} part(s)", dp.disk.path, dp.parts.len());
}
// Note:
// - Applying partitions, creating filesystems, mounting, and reporting
// will be wired in subsequent steps. For now this performs pre-flight
// checks and planning to exercise real code paths safely.
// Apply mode: perform destructive partition application now.
if ctx.apply {
info!("orchestrator: apply mode enabled; applying partition plan");
let part_results = partition::apply_partitions(&plan)?;
info!(
"orchestrator: applied partitions on {} disk(s), total parts created: {}",
plan.disks.len(),
part_results.len()
);
// Filesystem planning and creation
let fs_plan = zfs::plan_filesystems(&part_results, &ctx.cfg)?;
info!("orchestrator: filesystem plan contains {} spec(s)", fs_plan.specs.len());
let fs_results = zfs::make_filesystems(&fs_plan)?;
info!("orchestrator: created {} filesystem(s)", fs_results.len());
// Next steps (mounts, optional fstab, state report) will be wired in follow-ups.
return Ok(());
}
// Preview-only path
info!("orchestrator: pre-flight complete (idempotency checked, devices discovered, plan computed)");
// Optional: emit JSON summary via --show or write via --report

212
src/partition/plan.rs
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@@ -19,11 +19,12 @@
// ext: device-specific alignment or reserved areas configurable via cfg in the future.
// REGION: EXTENSION_POINTS-END
//
// REGION: SAFETY
// safety: must verify require_empty_disks before any modification.
// safety: must ensure unique partition GUIDs; identical labels are allowed when expected (e.g., ESP ZOSBOOT).
// safety: must call udev settle after partition table writes.
// REGION: SAFETY-END
// REGION: SAFETY
// safety: must verify require_empty_disks before any modification.
// safety: when UEFI-booted, suppress creating BIOS boot partition to avoid unnecessary ef02 on UEFI systems.
// safety: must ensure unique partition GUIDs; identical labels are allowed when expected (e.g., ESP ZOSBOOT).
// safety: must call udev settle after partition table writes.
// REGION: SAFETY-END
//
// REGION: ERROR_MAPPING
// errmap: external tool failure -> crate::Error::Tool { tool, status, stderr }.
@@ -42,7 +43,14 @@
//! See [fn plan_partitions](plan.rs:1) and
//! [fn apply_partitions](plan.rs:1).
use crate::{types::{Config, Topology}, device::Disk, Error, Result};
use crate::{
types::{Config, Topology},
device::Disk,
util::{run_cmd, run_cmd_capture, which_tool, udev_settle, is_efi_boot},
idempotency,
Error, Result,
};
use tracing::{debug, warn};
/// Partition roles supported by zosstorage.
#[derive(Debug, Clone, Copy)]
@@ -126,6 +134,8 @@ pub struct PartitionResult {
pub fn plan_partitions(disks: &[Disk], cfg: &Config) -> Result<PartitionPlan> {
let align = cfg.partitioning.alignment_mib;
let require_empty = cfg.partitioning.require_empty_disks;
// If system booted via UEFI, suppress the BIOS boot partition even if enabled in config.
let add_bios = cfg.partitioning.bios_boot.enabled && !is_efi_boot();
if disks.is_empty() {
return Err(Error::Partition("no disks provided to partition planner".into()));
@@ -137,7 +147,7 @@ pub fn plan_partitions(disks: &[Disk], cfg: &Config) -> Result<PartitionPlan> {
Topology::Single => {
let d0 = &disks[0];
let mut parts = Vec::new();
if cfg.partitioning.bios_boot.enabled {
if add_bios {
parts.push(PartitionSpec {
role: PartRole::BiosBoot,
size_mib: Some(cfg.partitioning.bios_boot.size_mib),
@@ -165,7 +175,7 @@ pub fn plan_partitions(disks: &[Disk], cfg: &Config) -> Result<PartitionPlan> {
// Disk 0: BIOS (opt) + ESP + Data
let mut parts0 = Vec::new();
if cfg.partitioning.bios_boot.enabled {
if add_bios {
parts0.push(PartitionSpec {
role: PartRole::BiosBoot,
size_mib: Some(cfg.partitioning.bios_boot.size_mib),
@@ -202,7 +212,7 @@ pub fn plan_partitions(disks: &[Disk], cfg: &Config) -> Result<PartitionPlan> {
// Disk 0: BIOS (opt) + ESP + Data
let mut parts0 = Vec::new();
if cfg.partitioning.bios_boot.enabled {
if add_bios {
parts0.push(PartitionSpec {
role: PartRole::BiosBoot,
size_mib: Some(cfg.partitioning.bios_boot.size_mib),
@@ -239,7 +249,7 @@ pub fn plan_partitions(disks: &[Disk], cfg: &Config) -> Result<PartitionPlan> {
// SSD: BIOS (opt) + ESP + Cache remainder
let mut parts_ssd = Vec::new();
if cfg.partitioning.bios_boot.enabled {
if add_bios {
parts_ssd.push(PartitionSpec {
role: PartRole::BiosBoot,
size_mib: Some(cfg.partitioning.bios_boot.size_mib),
@@ -276,13 +286,177 @@ pub fn plan_partitions(disks: &[Disk], cfg: &Config) -> Result<PartitionPlan> {
})
}
/// Apply the partition plan using system utilities (sgdisk) via util wrappers.
///
/// Safety:
/// - Must verify target disks are empty when required.
/// - Must ensure unique partition GUIDs.
/// - Should call udev settle after changes.
pub fn apply_partitions(_plan: &PartitionPlan) -> Result<Vec<PartitionResult>> {
// To be implemented: sgdisk orchestration + udev settle + GUID collection
todo!("shell out to sgdisk, trigger udev settle, collect partition GUIDs")
/**
Apply the partition plan using system utilities (sgdisk) via util wrappers.
Safety:
- Verifies target disks are empty when required (defense-in-depth; orchestrator should also enforce).
- Ensures unique partition GUIDs by relying on sgdisk defaults.
- Calls udev settle after changes to ensure /dev nodes exist.
Notes:
- Uses sgdisk -og to create a new GPT on empty disks.
- Adds partitions in declared order using -n (auto-aligned), -t (type code), -c (GPT name).
- Derives partition device paths: NVMe uses "pN" suffix; others use trailing "N".
- Captures per-partition GUID and geometry via `sgdisk -i <N> <disk>`.
*/
pub fn apply_partitions(plan: &PartitionPlan) -> Result<Vec<PartitionResult>> {
// Locate required tools
let Some(sgdisk) = which_tool("sgdisk")? else {
return Err(Error::Partition("sgdisk not found in PATH".into()));
};
// Helper: map role to GPT type code (gdisk codes)
fn type_code(role: PartRole) -> &'static str {
match role {
PartRole::BiosBoot => "ef02", // BIOS boot partition (for GRUB BIOS on GPT)
PartRole::Esp => "ef00", // EFI System Partition
PartRole::Data => "8300", // Linux filesystem
PartRole::Cache => "8300", // Treat cache as Linux filesystem (bcachefs)
}
}
// Helper: build partition device path for a given disk and partition number
fn part_dev_path(disk_path: &str, part_number: u32) -> String {
if disk_path.starts_with("/dev/nvme") {
format!("{disk_path}p{part_number}")
} else {
format!("{disk_path}{part_number}")
}
}
// Helper: sector size in bytes for disk (fallback 512 with warning)
fn sector_size_bytes(disk_path: &str) -> Result<u64> {
if let Some(blockdev) = which_tool("blockdev")? {
let out = run_cmd_capture(&[blockdev.as_str(), "--getss", disk_path])?;
let s = out.stdout.trim();
return s.parse::<u64>()
.map_err(|e| Error::Partition(format!("failed to parse sector size from blockdev for {}: {}", disk_path, e)));
}
warn!("blockdev not found; assuming 512-byte sectors for {}", disk_path);
Ok(512)
}
// Helper: parse sgdisk -i output to (unique_guid, first_sector, last_sector)
fn parse_sgdisk_info(info: &str) -> Result<(String, u64, u64)> {
let mut guid = String::new();
let mut first: Option<u64> = None;
let mut last: Option<u64> = None;
for line in info.lines() {
let line = line.trim();
if let Some(rest) = line.strip_prefix("Partition unique GUID:") {
guid = rest.trim().to_string();
} else if let Some(rest) = line.strip_prefix("First sector:") {
// Format: "First sector: 2048 (at 1024.0 KiB)"
let val = rest.trim().split_whitespace().next().unwrap_or("");
if !val.is_empty() {
first = Some(val.parse::<u64>().map_err(|e| Error::Partition(format!("parse first sector: {}", e)))?);
}
} else if let Some(rest) = line.strip_prefix("Last sector:") {
let val = rest.trim().split_whitespace().next().unwrap_or("");
if !val.is_empty() {
last = Some(val.parse::<u64>().map_err(|e| Error::Partition(format!("parse last sector: {}", e)))?);
}
}
}
let first = first.ok_or_else(|| Error::Partition("sgdisk -i missing First sector".into()))?;
let last = last.ok_or_else(|| Error::Partition("sgdisk -i missing Last sector".into()))?;
if guid.is_empty() {
return Err(Error::Partition("sgdisk -i missing Partition unique GUID".into()));
}
Ok((guid, first, last))
}
let mut results: Vec<PartitionResult> = Vec::new();
for dp in &plan.disks {
let disk_path = dp.disk.path.as_str();
// Defense-in-depth: verify emptiness when required
if plan.require_empty_disks {
let empty = idempotency::is_empty_disk(&dp.disk)?;
if !empty {
return Err(Error::Validation(format!(
"target disk {} is not empty (partitions or signatures present)",
dp.disk.path
)));
}
}
debug!("apply_partitions: creating GPT on {}", disk_path);
// Initialize (or re-initialize) a new empty GPT; requires truly empty disks per policy
run_cmd(&[sgdisk.as_str(), "-og", disk_path])?;
// Create partitions in order
for (idx0, spec) in dp.parts.iter().enumerate() {
let part_num = (idx0 as u32) + 1;
let size_arg = match spec.size_mib {
Some(mib) => format!("+{}M", mib), // rely on sgdisk MiB suffix support
None => String::from("0"), // consume remainder
};
// Use automatic aligned start (0) and specified size
let n_arg = format!("{}:0:{}", part_num, size_arg);
let t_arg = format!("{}:{}", part_num, type_code(spec.role));
let c_arg = format!("{}:{}", part_num, spec.gpt_name);
debug!(
"apply_partitions: {} -n {} -t {} -c {} {}",
sgdisk, n_arg, t_arg, c_arg, disk_path
);
run_cmd(&[
sgdisk.as_str(),
"-n", n_arg.as_str(),
"-t", t_arg.as_str(),
"-c", c_arg.as_str(),
disk_path,
])?;
}
// Settle udev so new partitions appear under /dev
udev_settle(5_000)?;
// Gather per-partition details and build results
let sector_bytes = sector_size_bytes(disk_path)?;
let mib_div: u64 = 1024 * 1024;
for (idx0, spec) in dp.parts.iter().enumerate() {
let part_num = (idx0 as u32) + 1;
// Query sgdisk for partition info
let i_arg = format!("{}", part_num);
let info_out = run_cmd_capture(&[
sgdisk.as_str(),
"-i", i_arg.as_str(),
disk_path,
])?;
let (unique_guid, first_sector, last_sector) = parse_sgdisk_info(&info_out.stdout)?;
let sectors = if last_sector >= first_sector {
last_sector - first_sector + 1
} else {
0
};
let start_mib = (first_sector.saturating_mul(sector_bytes)) / mib_div;
let size_mib = (sectors.saturating_mul(sector_bytes)) / mib_div;
let dev_path = part_dev_path(disk_path, part_num);
results.push(PartitionResult {
disk: dp.disk.path.clone(),
part_number: part_num,
role: spec.role,
gpt_name: spec.gpt_name.clone(),
uuid: unique_guid,
start_mib,
size_mib,
device_path: dev_path,
});
}
}
debug!("apply_partitions: created {} partition entries", results.len());
Ok(results)
}

11
src/util/mod.rs
View File

@@ -4,11 +4,13 @@
// api: util::run_cmd(args: &[&str]) -> crate::Result&lt;()&gt;
// api: util::run_cmd_capture(args: &[&str]) -> crate::Result&lt;CmdOutput&gt;
// api: util::udev_settle(timeout_ms: u64) -> crate::Result&lt;()&gt;
// api: util::is_efi_boot() -> bool
// REGION: API-END
//
// REGION: RESPONSIBILITIES
// - Centralize external tool discovery and invocation (sgdisk, blkid, mkfs.*, udevadm).
// - Provide capture and error mapping to crate::Error consistently.
// - Provide environment helpers (udev settle, boot mode detection).
// Non-goals: business logic (planning/validation), direct parsing of complex outputs beyond what callers need.
// REGION: RESPONSIBILITIES-END
//
@@ -39,6 +41,7 @@
use crate::{Error, Result};
use std::process::Command;
use std::path::Path;
use tracing::{debug, warn};
/// Captured output from an external tool invocation.
@@ -147,6 +150,14 @@ pub fn udev_settle(timeout_ms: u64) -> Result<()> {
}
}
/// Detect whether the current system booted via UEFI (initramfs-friendly).
///
/// Returns true when /sys/firmware/efi exists (standard on UEFI boots).
/// Returns false on legacy BIOS boots where that path is absent.
pub fn is_efi_boot() -> bool {
Path::new("/sys/firmware/efi").exists()
}
#[cfg(test)]
mod tests {
use super::*;