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use super::*;
pub(super) fn execute_plan(
store: &CheckpointStore,
plan: &RestorePlan,
cwd: &Path,
) -> RewindExecution {
execute_plan_internal(store, plan, cwd, None)
}
pub(super) fn execute_plan_internal(
store: &CheckpointStore,
plan: &RestorePlan,
cwd: &Path,
injected_failure: Option<&str>,
) -> RewindExecution {
execute_plan_internal_with_hooks(store, plan, cwd, injected_failure, || {}, || {}, || {})
}
fn mutation_status(
outcome: MutationOutcome,
committed_status: RestoreStatus,
reason: &mut Option<String>,
) -> RestoreStatus {
match outcome {
MutationOutcome::Committed { warning } => {
*reason = warning.map(str::to_string);
committed_status
}
MutationOutcome::Conflict(operation_reason) => {
*reason = Some(operation_reason.to_string());
RestoreStatus::SkipConflict
}
MutationOutcome::Failed(operation_reason) => {
*reason = Some(operation_reason.to_string());
RestoreStatus::SkipUnavailable
}
}
}
pub(super) fn execute_plan_internal_with_hooks(
store: &CheckpointStore,
plan: &RestorePlan,
cwd: &Path,
injected_failure: Option<&str>,
mut after_parent_acquired: impl FnMut(),
mut after_target_hashed: impl FnMut(),
mut after_quarantine_hashed: impl FnMut(),
) -> RewindExecution {
// This is the only ambient open in the target-operation path. All later
// reads, creates, renames, and removals use descendants of this handle.
let (canonical_cwd, root) = open_rewind_root(cwd);
let mut results = Vec::new();
for operation in &plan.operations {
let mut reason = None;
let status = if safe_rewind_target_path(store, &canonical_cwd, &operation.relative_path)
.is_err()
{
RestoreStatus::SkipUnavailable
} else {
match &operation.kind {
RestoreOperationKind::Restore {
pre,
expected_current,
} => {
let target = match root.as_ref() {
Some(root) => {
open_target_parent(root, &operation.relative_path, false, false)
}
None => Err(io::Error::new(ErrorKind::NotFound, "cwd unavailable")),
};
match target {
Err(_) => {
reason = Some("hash check failed".to_string());
RestoreStatus::SkipUnavailable
}
Ok(target) => {
after_parent_acquired();
let current = if injected_failure == Some("hash") {
Err(anyhow::anyhow!("injected failure"))
} else {
target_snapshot(&target).map_err(anyhow::Error::from)
};
match current {
Err(_) => {
reason = Some("hash check failed".to_string());
RestoreStatus::SkipUnavailable
}
Ok(current)
if current.as_ref().map(|snapshot| snapshot.hash.as_str())
!= Some(expected_current.sha256.as_str()) =>
{
RestoreStatus::SkipConflict
}
Ok(Some(current)) => {
after_target_hashed();
let outcome = write_rewind_blob(
store,
pre,
&target,
RewindBlobOptions {
expected_current_hash: Some(&expected_current.sha256),
target_mode: target_mode(¤t),
injected_failure,
inject_final_sync_failure: injected_failure
== Some("final sync"),
after_quarantine_hashed: &mut after_quarantine_hashed,
},
);
mutation_status(outcome, RestoreStatus::Restored, &mut reason)
}
Ok(None) => RestoreStatus::SkipConflict,
}
}
}
}
RestoreOperationKind::DeleteCreated { expected_current } => {
let target = match root.as_ref() {
Some(root) => {
open_target_parent(root, &operation.relative_path, false, false)
}
None => Err(io::Error::new(ErrorKind::NotFound, "cwd unavailable")),
};
match target {
Err(_) => {
reason = Some("hash check failed".to_string());
RestoreStatus::SkipUnavailable
}
Ok(target) => {
after_parent_acquired();
let current = if injected_failure == Some("hash") {
Err(anyhow::anyhow!("injected failure"))
} else {
target_snapshot(&target).map_err(anyhow::Error::from)
};
match current {
Err(_) => {
reason = Some("hash check failed".to_string());
RestoreStatus::SkipUnavailable
}
Ok(current)
if current.as_ref().map(|snapshot| snapshot.hash.as_str())
!= Some(expected_current.sha256.as_str()) =>
{
RestoreStatus::SkipConflict
}
Ok(Some(_)) => {
after_target_hashed();
let outcome = delete_target(
&target,
&expected_current.sha256,
injected_failure == Some("delete"),
injected_failure == Some("final sync"),
&mut after_quarantine_hashed,
);
mutation_status(
outcome,
RestoreStatus::DeletedCreated,
&mut reason,
)
}
Ok(None) => RestoreStatus::SkipConflict,
}
}
}
}
RestoreOperationKind::ResurrectDeleted { pre } => {
let target = match root.as_ref() {
Some(root) => {
open_target_parent(root, &operation.relative_path, false, false)
}
None => Err(io::Error::new(ErrorKind::NotFound, "cwd unavailable")),
};
match target {
Ok(target) => {
after_parent_acquired();
let current = target_snapshot(&target).map_err(anyhow::Error::from);
match current {
Err(_) => {
reason = Some("hash check failed".to_string());
RestoreStatus::SkipUnavailable
}
Ok(Some(_)) => RestoreStatus::SkipConflict,
Ok(None) => {
let outcome = write_rewind_blob(
store,
pre,
&target,
RewindBlobOptions {
expected_current_hash: None,
target_mode: None,
injected_failure,
inject_final_sync_failure: injected_failure
== Some("final sync"),
after_quarantine_hashed: &mut after_quarantine_hashed,
},
);
mutation_status(
outcome,
RestoreStatus::ResurrectedDeleted,
&mut reason,
)
}
}
}
Err(error) if error.kind() == ErrorKind::NotFound => {
// Do not create missing parents until the blob has
// been read successfully. This keeps blob failures
// side-effect free while retaining capability safety.
let bytes = match read_rewind_blob(store, pre, injected_failure) {
Ok(bytes) => bytes,
Err(failure) => {
reason = Some(failure.to_string());
Vec::new()
}
};
if reason.is_some() {
RestoreStatus::SkipUnavailable
} else {
let target = match root.as_ref() {
Some(root) => open_target_parent(
root,
&operation.relative_path,
true,
injected_failure == Some("ancestor sync"),
),
None => {
Err(io::Error::new(ErrorKind::NotFound, "cwd unavailable"))
}
};
match target {
Err(_) => {
reason = Some("write failed".to_string());
RestoreStatus::SkipUnavailable
}
Ok(target) => {
after_parent_acquired();
match target_snapshot(&target) {
Err(_) => {
reason = Some("hash check failed".to_string());
RestoreStatus::SkipUnavailable
}
Ok(Some(_)) => RestoreStatus::SkipConflict,
Ok(None) => {
let outcome = install_new_target(
&target,
&bytes,
injected_failure == Some("write"),
injected_failure == Some("final sync"),
);
mutation_status(
outcome,
RestoreStatus::ResurrectedDeleted,
&mut reason,
)
}
}
}
}
}
}
Err(_) => {
reason = Some("write failed".to_string());
RestoreStatus::SkipUnavailable
}
}
}
RestoreOperationKind::SkipConflict {
reason: operation_reason,
} => {
reason = Some(sanitized_diagnostic(operation_reason.clone()));
RestoreStatus::SkipConflict
}
RestoreOperationKind::SkipUnavailable {
reason: operation_reason,
} => {
reason = Some(sanitized_diagnostic(operation_reason.clone()));
RestoreStatus::SkipUnavailable
}
}
};
results.push(RestoreOperationResult {
relative_path: operation.relative_path.clone(),
status,
reason,
});
}
RewindExecution { results }
}
pub(super) fn read_rewind_blob(
store: &CheckpointStore,
blob: &SnapshotBlobRef,
injected_failure: Option<&str>,
) -> Result<Vec<u8>, &'static str> {
if injected_failure == Some("blob read") {
return Err("blob read failed");
}
store.read_blob(blob).map_err(|_| "blob read failed")
}