yoi/crates/pod/src/runtime/scope_lock.rs
2026-04-28 18:52:58 +09:00

1204 lines
38 KiB
Rust

//! Machine-wide scope allocation registry.
//!
//! A single JSON file at `<runtime_dir>/scope.lock` records every live
//! Pod's scope allocation (see [`manifest::paths::scope_lock_path`] for
//! how the path is resolved). File-level `flock(2)` serialises access
//! across processes so spawn sequences from unrelated Pods can't race.
//!
//! Each Pod, when starting, acquires the lock, reclaims stale entries
//! (Pods whose PID has died), checks that its requested write scope
//! does not overlap any other allocation's effective write scope, and
//! registers itself. When it exits normally, it removes its entry and
//! returns delegated scope to its `delegated_from` parent. Crash
//! recovery rides on the next Pod that opens the file — no background
//! reaper.
use std::fs::{DirBuilder, File, OpenOptions};
use std::io::{self, Read, Seek, SeekFrom, Write};
use std::os::unix::fs::{DirBuilderExt, OpenOptionsExt};
use std::path::{Path, PathBuf};
use fs4::fs_std::FileExt;
use manifest::{Permission, ScopeRule, paths};
use serde::{Deserialize, Serialize};
use session_store::SessionId;
/// On-disk representation of the allocation table.
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
pub struct LockFile {
#[serde(default)]
pub allocations: Vec<Allocation>,
}
/// One Pod's scope allocation.
///
/// `scope_allow` is the full set of allow rules the Pod was granted.
/// Portions delegated out to child Pods are **not** subtracted in
/// storage — the effective write scope is derived on the fly by
/// removing rules owned by any Pod whose `delegated_from` points to
/// this one. Keeping the raw allow set makes reparenting (stale
/// reclaim) trivial.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Allocation {
/// Pod name — also the identity used throughout orchestration.
pub pod_name: String,
/// Owning process. Checked with `kill(pid, 0)` for stale detection.
pub pid: u32,
/// Pod's Unix socket path.
pub socket: PathBuf,
/// Allow rules granted to this Pod (write + read).
pub scope_allow: Vec<ScopeRule>,
/// Name of the Pod that delegated scope to this one, or `None` for
/// a top-level Pod started directly by a human.
pub delegated_from: Option<String>,
/// Session ID this Pod is currently writing to. `None` means this
/// is a pre-reservation made by a spawner via [`delegate_scope`]
/// before the child has come up; the child fills it in at
/// [`adopt_allocation`] time.
#[serde(default)]
pub session_id: Option<SessionId>,
}
impl LockFile {
pub fn find(&self, pod_name: &str) -> Option<&Allocation> {
self.allocations.iter().find(|a| a.pod_name == pod_name)
}
pub fn find_mut(&mut self, pod_name: &str) -> Option<&mut Allocation> {
self.allocations.iter_mut().find(|a| a.pod_name == pod_name)
}
/// Find the allocation currently writing to `session_id`. Skips
/// pre-reservations whose `session_id` is still `None`.
pub fn find_by_session(&self, session_id: SessionId) -> Option<&Allocation> {
self.allocations
.iter()
.find(|a| a.session_id == Some(session_id))
}
}
/// Default on-disk path: `<runtime_dir>/scope.lock` resolved via
/// [`manifest::paths::scope_lock_path`]. Tests should point this
/// elsewhere by setting `INSOMNIA_HOME` or `INSOMNIA_RUNTIME_DIR` to a
/// tempdir.
pub fn default_lock_path() -> io::Result<PathBuf> {
paths::scope_lock_path().ok_or_else(|| {
io::Error::new(
io::ErrorKind::NotFound,
"could not resolve scope.lock path (no INSOMNIA_HOME / \
INSOMNIA_RUNTIME_DIR / XDG_RUNTIME_DIR / HOME)",
)
})
}
/// RAII guard over an exclusively-locked lock file.
///
/// The file is kept open for the lifetime of the guard; `flock(LOCK_EX)`
/// is released automatically on drop. Mutations go through
/// [`LockFileGuard::data_mut`] and are committed with
/// [`LockFileGuard::save`] before dropping — callers who mutate but
/// never call `save` leave the table unchanged, which is the right
/// behaviour for error paths.
pub struct LockFileGuard {
file: File,
data: LockFile,
}
impl LockFileGuard {
/// Open the lock file at `path` (creating it + parent dirs if
/// needed), acquire an exclusive `flock`, then parse the contents.
///
/// An empty file is treated as an empty allocation table.
///
/// File is created with mode `0600` and its parent directory with
/// mode `0700` so no other user on the machine can read the
/// allocation table. Existing files/directories are left alone.
pub fn open(path: &Path) -> io::Result<Self> {
if let Some(parent) = path.parent() {
DirBuilder::new()
.recursive(true)
.mode(0o700)
.create(parent)?;
}
let file = OpenOptions::new()
.read(true)
.write(true)
.create(true)
.truncate(false)
.mode(0o600)
.open(path)?;
FileExt::lock_exclusive(&file)?;
let mut this = Self {
file,
data: LockFile::default(),
};
this.reload()?;
Ok(this)
}
fn reload(&mut self) -> io::Result<()> {
self.file.seek(SeekFrom::Start(0))?;
let mut buf = String::new();
self.file.read_to_string(&mut buf)?;
self.data = if buf.trim().is_empty() {
LockFile::default()
} else {
serde_json::from_str(&buf).map_err(|e| {
io::Error::new(
io::ErrorKind::InvalidData,
format!("scope.lock parse error: {e}"),
)
})?
};
Ok(())
}
pub fn data(&self) -> &LockFile {
&self.data
}
pub fn data_mut(&mut self) -> &mut LockFile {
&mut self.data
}
/// Serialise `self.data` back to the file (truncate + rewrite).
pub fn save(&mut self) -> io::Result<()> {
let json = serde_json::to_vec_pretty(&self.data).map_err(io::Error::other)?;
self.file.seek(SeekFrom::Start(0))?;
self.file.set_len(0)?;
self.file.write_all(&json)?;
self.file.sync_data()?;
Ok(())
}
}
impl Drop for LockFileGuard {
fn drop(&mut self) {
let _ = FileExt::unlock(&self.file);
}
}
/// Whether `a` and `b` claim any overlapping concrete path.
///
/// Recursive rules cover `target/**`; non-recursive rules cover the
/// target itself and its direct children. The four cases enumerate
/// when those coverage sets intersect.
pub(crate) fn rules_overlap(a: &ScopeRule, b: &ScopeRule) -> bool {
match (a.recursive, b.recursive) {
(true, true) => a.target.starts_with(&b.target) || b.target.starts_with(&a.target),
(true, false) => {
// a covers a.target/**; b covers {b.target, b.target/*}.
b.target.starts_with(&a.target) || a.target.parent() == Some(b.target.as_path())
}
(false, true) => {
a.target.starts_with(&b.target) || b.target.parent() == Some(a.target.as_path())
}
(false, false) => {
a.target == b.target
|| a.target.parent() == Some(b.target.as_path())
|| b.target.parent() == Some(a.target.as_path())
}
}
}
/// Does `cover` fully contain `inner`'s claimed paths?
fn covers_fully(cover: &ScopeRule, inner: &ScopeRule) -> bool {
if cover.permission < inner.permission {
return false;
}
if cover.recursive {
inner.target.starts_with(&cover.target)
} else {
inner.target == cover.target && !inner.recursive
}
}
/// Check whether `rule` is contained in `parent`'s effective write
/// scope: its allow set covers `rule`, and no child of `parent` has
/// already taken a piece that would overlap `rule`.
pub fn is_within_effective_write(lock: &LockFile, parent: &str, rule: &ScopeRule) -> bool {
let Some(alloc) = lock.find(parent) else {
return false;
};
if rule.permission != Permission::Write {
return alloc.scope_allow.iter().any(|r| covers_fully(r, rule));
}
let covered = alloc
.scope_allow
.iter()
.filter(|r| r.permission == Permission::Write)
.any(|r| covers_fully(r, rule));
if !covered {
return false;
}
let child_conflict = lock
.allocations
.iter()
.filter(|a| a.delegated_from.as_deref() == Some(parent))
.flat_map(|a| a.scope_allow.iter())
.filter(|r| r.permission == Permission::Write)
.any(|r| rules_overlap(r, rule));
!child_conflict
}
/// Find the Pod that actually owns a write scope overlapping `rule`.
///
/// Walks the delegation tree: if an allocation overlaps `rule`, we
/// descend into its children and return the deepest overlapping node
/// as the true owner. `exempt` names a Pod whose ownership is
/// permitted (used during delegation: the spawner itself is allowed
/// to still own the rule's region because it is handing it down).
pub fn find_conflict_owner(
lock: &LockFile,
rule: &ScopeRule,
exempt: Option<&str>,
) -> Option<String> {
if rule.permission != Permission::Write {
return None;
}
for alloc in lock
.allocations
.iter()
.filter(|a| a.delegated_from.is_none())
{
if let Some(owner) = find_conflict_in_subtree(lock, alloc, rule) {
if Some(owner.as_str()) == exempt {
continue;
}
return Some(owner);
}
}
None
}
fn find_conflict_in_subtree(
lock: &LockFile,
alloc: &Allocation,
rule: &ScopeRule,
) -> Option<String> {
let overlaps_here = alloc
.scope_allow
.iter()
.filter(|r| r.permission == Permission::Write)
.any(|r| rules_overlap(r, rule));
if !overlaps_here {
return None;
}
for child in lock
.allocations
.iter()
.filter(|a| a.delegated_from.as_deref() == Some(alloc.pod_name.as_str()))
{
if let Some(owner) = find_conflict_in_subtree(lock, child, rule) {
return Some(owner);
}
}
Some(alloc.pod_name.clone())
}
// ---------------------------------------------------------------------------
// Mutating operations
// ---------------------------------------------------------------------------
/// Register a top-level Pod (started directly by a human, no
/// delegation parent). Reclaims stale entries before checking
/// conflicts so a crashed Pod's allocation doesn't block the new one.
pub fn register_pod(
guard: &mut LockFileGuard,
pod_name: String,
pid: u32,
socket: PathBuf,
scope_allow: Vec<ScopeRule>,
session_id: SessionId,
) -> Result<(), ScopeLockError> {
reclaim_stale(guard);
if guard.data().find(&pod_name).is_some() {
return Err(ScopeLockError::DuplicatePodName(pod_name));
}
for rule in scope_allow
.iter()
.filter(|r| r.permission == Permission::Write)
{
if let Some(competitor) = find_conflict_owner(guard.data(), rule, None) {
return Err(ScopeLockError::WriteConflict {
competitor,
rule: rule.clone(),
});
}
}
guard.data_mut().allocations.push(Allocation {
pod_name,
pid,
socket,
scope_allow,
delegated_from: None,
session_id: Some(session_id),
});
guard.save()?;
Ok(())
}
/// Register a spawned Pod whose scope is delegated from `spawner`.
/// The requested scope must be within `spawner`'s effective write
/// scope; overlap with any Pod other than `spawner` is a conflict.
pub fn delegate_scope(
guard: &mut LockFileGuard,
spawner: &str,
spawned: String,
pid: u32,
socket: PathBuf,
scope_allow: Vec<ScopeRule>,
) -> Result<(), ScopeLockError> {
reclaim_stale(guard);
if guard.data().find(&spawned).is_some() {
return Err(ScopeLockError::DuplicatePodName(spawned));
}
if guard.data().find(spawner).is_none() {
return Err(ScopeLockError::UnknownPod(spawner.into()));
}
for rule in &scope_allow {
if !is_within_effective_write(guard.data(), spawner, rule) {
return Err(ScopeLockError::NotSubset {
spawner: spawner.into(),
rule: rule.clone(),
});
}
if rule.permission == Permission::Write {
if let Some(competitor) = find_conflict_owner(guard.data(), rule, Some(spawner)) {
return Err(ScopeLockError::WriteConflict {
competitor,
rule: rule.clone(),
});
}
}
}
guard.data_mut().allocations.push(Allocation {
pod_name: spawned,
pid,
socket,
scope_allow,
delegated_from: Some(spawner.into()),
// Pre-reservation. The child fills in its own session_id when
// it calls `adopt_allocation` after the worker is built.
session_id: None,
});
guard.save()?;
Ok(())
}
/// Remove a Pod's allocation. Surviving children are reparented to
/// the removed Pod's own `delegated_from`, so the delegation tree
/// stays connected.
pub fn release_pod(guard: &mut LockFileGuard, pod_name: &str) -> Result<(), ScopeLockError> {
let idx = guard
.data()
.allocations
.iter()
.position(|a| a.pod_name == pod_name);
let Some(idx) = idx else {
return Err(ScopeLockError::UnknownPod(pod_name.into()));
};
let removed = guard.data().allocations[idx].clone();
for alloc in guard.data_mut().allocations.iter_mut() {
if alloc.delegated_from.as_deref() == Some(pod_name) {
alloc.delegated_from.clone_from(&removed.delegated_from);
}
}
guard.data_mut().allocations.remove(idx);
guard.save()?;
Ok(())
}
/// Remove allocations whose PID is dead, reparenting children to the
/// dead Pod's `delegated_from`. Idempotent and best-effort — I/O
/// errors on save are swallowed so a crashed Pod's entry never blocks
/// forward progress.
pub fn reclaim_stale(guard: &mut LockFileGuard) {
reclaim_stale_with(guard, pid_alive);
}
/// Test seam: stale reclaim with a caller-supplied liveness probe.
pub fn reclaim_stale_with(guard: &mut LockFileGuard, mut is_alive: impl FnMut(u32) -> bool) {
let dead: Vec<String> = guard
.data()
.allocations
.iter()
.filter(|a| !is_alive(a.pid))
.map(|a| a.pod_name.clone())
.collect();
if dead.is_empty() {
return;
}
for name in &dead {
let Some(idx) = guard
.data()
.allocations
.iter()
.position(|a| a.pod_name == *name)
else {
continue;
};
let removed = guard.data().allocations[idx].clone();
for alloc in guard.data_mut().allocations.iter_mut() {
if alloc.delegated_from.as_deref() == Some(name.as_str()) {
alloc.delegated_from.clone_from(&removed.delegated_from);
}
}
guard.data_mut().allocations.remove(idx);
}
let _ = guard.save();
}
/// `kill(pid, 0)` — returns true if the process exists (even when we
/// don't own it), false only on ESRCH.
fn pid_alive(pid: u32) -> bool {
if pid == 0 {
return false;
}
let ret = unsafe { libc::kill(pid as libc::pid_t, 0) };
if ret == 0 {
return true;
}
io::Error::last_os_error()
.raw_os_error()
.map(|e| e != libc::ESRCH)
.unwrap_or(false)
}
// ---------------------------------------------------------------------------
// Lifecycle guard
// ---------------------------------------------------------------------------
/// Owned allocation: on drop, opens the lock file and releases this
/// Pod's entry. The guard keeps only the name + lock-file path; it
/// does not hold the `flock` for the Pod's lifetime.
#[derive(Debug)]
pub struct ScopeAllocationGuard {
pod_name: String,
lock_path: PathBuf,
}
impl ScopeAllocationGuard {
pub fn pod_name(&self) -> &str {
&self.pod_name
}
pub fn lock_path(&self) -> &Path {
&self.lock_path
}
}
impl Drop for ScopeAllocationGuard {
fn drop(&mut self) {
if let Ok(mut guard) = LockFileGuard::open(&self.lock_path) {
let _ = release_pod(&mut guard, &self.pod_name);
}
}
}
/// Open the default lock file, register a top-level Pod, and return a
/// guard that will release the allocation on drop.
pub fn install_top_level(
pod_name: String,
pid: u32,
socket: PathBuf,
scope_allow: Vec<ScopeRule>,
session_id: SessionId,
) -> Result<ScopeAllocationGuard, ScopeLockError> {
let lock_path = default_lock_path()?;
let mut guard = LockFileGuard::open(&lock_path)?;
register_pod(
&mut guard,
pod_name.clone(),
pid,
socket,
scope_allow,
session_id,
)?;
Ok(ScopeAllocationGuard {
pod_name,
lock_path,
})
}
/// Take ownership of an existing allocation that was pre-registered by
/// a spawning Pod.
///
/// The spawning flow is two-stage: the spawner calls [`delegate_scope`]
/// (with its own pid as a live placeholder, `session_id = None`), then
/// exec's the child; the child, once running, calls this function to
/// rewrite the allocation's pid + session_id to its own and claim the
/// `ScopeAllocationGuard` so the entry is released when the child
/// exits.
pub fn adopt_allocation(
pod_name: String,
new_pid: u32,
session_id: SessionId,
) -> Result<ScopeAllocationGuard, ScopeLockError> {
let lock_path = default_lock_path()?;
let mut guard = LockFileGuard::open(&lock_path)?;
let alloc = guard
.data_mut()
.find_mut(&pod_name)
.ok_or_else(|| ScopeLockError::UnknownPod(pod_name.clone()))?;
alloc.pid = new_pid;
alloc.session_id = Some(session_id);
guard.save()?;
Ok(ScopeAllocationGuard {
pod_name,
lock_path,
})
}
/// Information about a Pod that currently holds an allocation for a
/// given session.
#[derive(Debug, Clone)]
pub struct SessionLockInfo {
pub pod_name: String,
pub socket: PathBuf,
pub pid: u32,
}
/// Open the default lock file, reclaim stale entries, and return the
/// allocation currently writing to `session_id`, if any.
///
/// Used by `Pod::restore_from_manifest` to refuse a resume that would
/// race a live writer on the same source session.
pub fn lookup_session(session_id: SessionId) -> Result<Option<SessionLockInfo>, ScopeLockError> {
let lock_path = default_lock_path()?;
let mut guard = LockFileGuard::open(&lock_path)?;
reclaim_stale(&mut guard);
Ok(guard.data().find_by_session(session_id).map(|a| {
SessionLockInfo {
pod_name: a.pod_name.clone(),
socket: a.socket.clone(),
pid: a.pid,
}
}))
}
/// Errors raised by the mutating scope-lock operations.
#[derive(Debug, thiserror::Error)]
pub enum ScopeLockError {
#[error("I/O error on scope.lock: {0}")]
Io(#[from] io::Error),
#[error("pod name `{0}` is already registered")]
DuplicatePodName(String),
#[error("requested scope `{}` conflicts with pod `{competitor}`", .rule.target.display())]
WriteConflict { competitor: String, rule: ScopeRule },
#[error(
"requested scope `{}` is not within spawner `{spawner}`'s effective scope",
.rule.target.display()
)]
NotSubset { spawner: String, rule: ScopeRule },
#[error("pod `{0}` is not registered")]
UnknownPod(String),
}
#[cfg(test)]
mod tests {
use super::*;
use manifest::Permission;
use std::sync::{LazyLock, Mutex, MutexGuard};
use tempfile::TempDir;
/// Serialises tests that mutate runtime-dir env vars. The test
/// harness runs tests on multiple threads inside a single process,
/// so env-var writes from one test would otherwise leak into a
/// parallel test's `default_lock_path()` lookup.
fn sid() -> SessionId {
session_store::new_session_id()
}
static ENV_LOCK: LazyLock<Mutex<()>> = LazyLock::new(|| Mutex::new(()));
/// Sandbox `INSOMNIA_RUNTIME_DIR` to a tempdir for the duration of
/// a test; restore the previous value (and any `INSOMNIA_HOME` /
/// `XDG_RUNTIME_DIR` that would otherwise outrank it) on drop.
struct RuntimeDirSandbox {
prev_runtime: Option<String>,
prev_home: Option<String>,
prev_xdg: Option<String>,
_guard: MutexGuard<'static, ()>,
}
impl RuntimeDirSandbox {
fn new(dir: &Path) -> Self {
let guard = ENV_LOCK.lock().unwrap_or_else(|e| e.into_inner());
let prev_runtime = std::env::var("INSOMNIA_RUNTIME_DIR").ok();
let prev_home = std::env::var("INSOMNIA_HOME").ok();
let prev_xdg = std::env::var("XDG_RUNTIME_DIR").ok();
// SAFETY: ENV_LOCK serialises env writes across this test
// module; other modules that touch env vars rely on their
// own lock or `serial_test`.
unsafe {
std::env::remove_var("INSOMNIA_HOME");
std::env::remove_var("XDG_RUNTIME_DIR");
std::env::set_var("INSOMNIA_RUNTIME_DIR", dir);
}
Self {
prev_runtime,
prev_home,
prev_xdg,
_guard: guard,
}
}
}
impl Drop for RuntimeDirSandbox {
fn drop(&mut self) {
unsafe {
match &self.prev_runtime {
Some(v) => std::env::set_var("INSOMNIA_RUNTIME_DIR", v),
None => std::env::remove_var("INSOMNIA_RUNTIME_DIR"),
}
match &self.prev_home {
Some(v) => std::env::set_var("INSOMNIA_HOME", v),
None => std::env::remove_var("INSOMNIA_HOME"),
}
match &self.prev_xdg {
Some(v) => std::env::set_var("XDG_RUNTIME_DIR", v),
None => std::env::remove_var("XDG_RUNTIME_DIR"),
}
}
}
}
fn write_rule(path: &str, recursive: bool) -> ScopeRule {
ScopeRule {
target: PathBuf::from(path),
permission: Permission::Write,
recursive,
}
}
fn sock(name: &str) -> PathBuf {
PathBuf::from(format!("/tmp/{name}.sock"))
}
fn open_empty(path: &Path) -> LockFileGuard {
LockFileGuard::open(path).unwrap()
}
#[test]
fn open_creates_empty_lock_file() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let guard = LockFileGuard::open(&path).unwrap();
assert!(guard.data().allocations.is_empty());
assert!(path.exists());
}
#[test]
fn open_creates_file_with_owner_only_permissions() {
use std::os::unix::fs::PermissionsExt;
let dir = TempDir::new().unwrap();
let parent = dir.path().join("insomnia");
let path = parent.join("scope.lock");
let _guard = LockFileGuard::open(&path).unwrap();
let file_mode = std::fs::metadata(&path).unwrap().permissions().mode() & 0o777;
assert_eq!(file_mode, 0o600, "file mode = {file_mode:o}");
let dir_mode = std::fs::metadata(&parent).unwrap().permissions().mode() & 0o777;
assert_eq!(dir_mode, 0o700, "dir mode = {dir_mode:o}");
}
#[test]
fn save_and_reopen_roundtrip() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
{
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
}
let guard = LockFileGuard::open(&path).unwrap();
assert_eq!(guard.data().allocations.len(), 1);
assert_eq!(guard.data().allocations[0].pod_name, "a");
}
#[test]
fn rules_overlap_prefix_relation() {
assert!(rules_overlap(
&write_rule("/src", true),
&write_rule("/src/core", true)
));
assert!(rules_overlap(
&write_rule("/src/core", true),
&write_rule("/src", true),
));
assert!(!rules_overlap(
&write_rule("/src", true),
&write_rule("/docs", true),
));
}
#[test]
fn rules_overlap_non_recursive() {
assert!(!rules_overlap(
&write_rule("/src", false),
&write_rule("/src/a/b", true),
));
assert!(rules_overlap(
&write_rule("/src", false),
&write_rule("/src/child", false),
));
}
#[test]
fn register_detects_write_conflict() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
let err = register_pod(
&mut g,
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src/core", true)],
sid(),
)
.unwrap_err();
match err {
ScopeLockError::WriteConflict { competitor, .. } => assert_eq!(competitor, "a"),
other => panic!("expected WriteConflict, got {other:?}"),
}
}
#[test]
fn duplicate_pod_name_rejected() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
let err = register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a2"),
vec![write_rule("/docs", true)],
sid(),
)
.unwrap_err();
assert!(matches!(err, ScopeLockError::DuplicatePodName(ref n) if n == "a"));
}
#[test]
fn delegate_must_be_subset() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
let err = delegate_scope(
&mut g,
"a",
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/docs", true)],
)
.unwrap_err();
assert!(matches!(err, ScopeLockError::NotSubset { .. }));
}
#[test]
fn delegate_succeeds_within_parent_scope() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
delegate_scope(
&mut g,
"a",
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src/core", true)],
)
.unwrap();
assert_eq!(g.data().allocations.len(), 2);
// A's effective write no longer covers /src/core because B has it.
assert!(!is_within_effective_write(
g.data(),
"a",
&write_rule("/src/core", true)
));
// A still covers its own uninvolved areas.
assert!(is_within_effective_write(
g.data(),
"a",
&write_rule("/src/other", true)
));
}
#[test]
fn delegate_rejects_sibling_overlap() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
delegate_scope(
&mut g,
"a",
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src/core", true)],
)
.unwrap();
// Sibling C from A tries to take /src/core/sub — already under B's scope.
let err = delegate_scope(
&mut g,
"a",
"c".into(),
std::process::id(),
sock("c"),
vec![write_rule("/src/core/sub", true)],
)
.unwrap_err();
// NotSubset fires first because /src/core is no longer in A's effective.
assert!(matches!(err, ScopeLockError::NotSubset { .. }));
}
#[test]
fn release_reparents_children() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
delegate_scope(
&mut g,
"a",
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src/core", true)],
)
.unwrap();
delegate_scope(
&mut g,
"b",
"d".into(),
std::process::id(),
sock("d"),
vec![write_rule("/src/core/x", true)],
)
.unwrap();
release_pod(&mut g, "b").unwrap();
// D should now list A as its delegated_from.
let d = g.data().find("d").unwrap();
assert_eq!(d.delegated_from.as_deref(), Some("a"));
assert!(g.data().find("b").is_none());
}
#[test]
fn reclaim_stale_reparents_and_removes_dead_entries() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
delegate_scope(
&mut g,
"a",
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src/core", true)],
)
.unwrap();
delegate_scope(
&mut g,
"b",
"d".into(),
std::process::id(),
sock("d"),
vec![write_rule("/src/core/x", true)],
)
.unwrap();
// Simulate B crashing by rewriting its pid to one the probe
// will treat as dead.
let fake_dead_pid: u32 = 0xffff_fff0;
for alloc in g.data_mut().allocations.iter_mut() {
if alloc.pod_name == "b" {
alloc.pid = fake_dead_pid;
}
}
reclaim_stale_with(&mut g, |pid| pid != fake_dead_pid);
assert!(g.data().find("b").is_none());
let d = g.data().find("d").unwrap();
assert_eq!(d.delegated_from.as_deref(), Some("a"));
}
fn read_rule(path: &str, recursive: bool) -> ScopeRule {
ScopeRule {
target: PathBuf::from(path),
permission: Permission::Read,
recursive,
}
}
#[test]
fn read_rules_do_not_conflict_with_write() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
// B only reads under the same tree — allowed.
register_pod(
&mut g,
"b".into(),
std::process::id(),
sock("b"),
vec![read_rule("/src", true)],
sid(),
)
.unwrap();
assert_eq!(g.data().allocations.len(), 2);
}
#[test]
fn releasing_pod_reopens_scope_for_fresh_registration() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
release_pod(&mut g, "a").unwrap();
register_pod(
&mut g,
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
}
#[test]
fn delegated_scope_returns_to_parent_on_release() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
delegate_scope(
&mut g,
"a",
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src/core", true)],
)
.unwrap();
assert!(!is_within_effective_write(
g.data(),
"a",
&write_rule("/src/core", true)
));
release_pod(&mut g, "b").unwrap();
// /src/core is back in A's effective write scope.
assert!(is_within_effective_write(
g.data(),
"a",
&write_rule("/src/core", true)
));
}
#[test]
fn scope_allocation_guard_releases_on_drop() {
let dir = TempDir::new().unwrap();
let _sandbox = RuntimeDirSandbox::new(dir.path());
let lock_path = dir.path().join("scope.lock");
let guard = install_top_level(
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
{
let g = LockFileGuard::open(&lock_path).unwrap();
assert!(g.data().find("a").is_some());
}
drop(guard);
{
let g = LockFileGuard::open(&lock_path).unwrap();
assert!(g.data().find("a").is_none());
}
}
#[test]
fn adopt_allocation_rewrites_pid_and_releases_on_drop() {
let dir = TempDir::new().unwrap();
let _sandbox = RuntimeDirSandbox::new(dir.path());
let lock_path = dir.path().join("scope.lock");
// Pre-register an allocation under spawner's pid, as delegate_scope would.
{
let mut g = LockFileGuard::open(&lock_path).unwrap();
delegate_placeholder(&mut g, "child", std::process::id());
}
let child_pid = std::process::id().wrapping_add(1);
let guard = adopt_allocation("child".into(), child_pid, sid()).unwrap();
{
let g = LockFileGuard::open(&lock_path).unwrap();
let alloc = g.data().find("child").unwrap();
assert_eq!(alloc.pid, child_pid);
}
drop(guard);
{
let g = LockFileGuard::open(&lock_path).unwrap();
assert!(g.data().find("child").is_none());
}
}
#[test]
fn adopt_allocation_errors_on_unknown_pod() {
let dir = TempDir::new().unwrap();
let _sandbox = RuntimeDirSandbox::new(dir.path());
let err = adopt_allocation("ghost".into(), 42, sid()).unwrap_err();
assert!(matches!(err, ScopeLockError::UnknownPod(ref n) if n == "ghost"));
}
/// Mimic what the spawner does before the child comes up: push an
/// allocation for the child carrying the spawner's (live) pid as a
/// placeholder. Exists only in tests.
fn delegate_placeholder(g: &mut LockFileGuard, pod_name: &str, placeholder_pid: u32) {
g.data_mut().allocations.push(Allocation {
pod_name: pod_name.to_string(),
pid: placeholder_pid,
socket: sock(pod_name),
scope_allow: vec![write_rule("/tmp/child", true)],
delegated_from: None,
session_id: None,
});
g.save().unwrap();
}
#[test]
fn conflict_detection_descends_to_real_owner() {
let dir = TempDir::new().unwrap();
let path = dir.path().join("scope.lock");
let mut g = open_empty(&path);
register_pod(
&mut g,
"a".into(),
std::process::id(),
sock("a"),
vec![write_rule("/src", true)],
sid(),
)
.unwrap();
delegate_scope(
&mut g,
"a",
"b".into(),
std::process::id(),
sock("b"),
vec![write_rule("/src/core", true)],
)
.unwrap();
// A different top-level Pod trying to register /src/core/x
// should be blamed on B (deepest owner), not A.
let err = register_pod(
&mut g,
"x".into(),
std::process::id(),
sock("x"),
vec![write_rule("/src/core/x", true)],
sid(),
)
.unwrap_err();
match err {
ScopeLockError::WriteConflict { competitor, .. } => assert_eq!(competitor, "b"),
other => panic!("expected WriteConflict, got {other:?}"),
}
}
}