cadmpeg_core/decode/error.rs
1// SPDX-License-Identifier: Apache-2.0
2//! Resource-failure types shared by the budget and [`CodecError`].
3//!
4//! [`CodecError`]: crate::CodecError
5
6use super::space::SpaceId;
7
8/// Which resource a limit governs.
9#[derive(Debug, Clone, Copy, PartialEq, Eq)]
10pub enum ResourceDimension {
11 /// Physical input bytes read at the root.
12 InputBytes,
13 /// Bytes produced by decompression.
14 DecompressedBytes,
15 /// Bytes held by scoped materializations.
16 MaterializedBytes,
17 /// Bytes retained for the decode session outside expansion output.
18 RetainedBytes,
19 /// Admitted semantic or native entities.
20 Entities,
21 /// Admitted items across decoded collections.
22 CollectionItems,
23 /// Active recursive nesting depth.
24 RecursionDepth,
25 /// Algorithm work units.
26 WorkUnits,
27 /// A codec-local resource dimension.
28 Codec(&'static str),
29}
30
31/// Why a resource request failed.
32#[derive(Debug, Clone, Copy, PartialEq, Eq)]
33pub enum ResourceFailure {
34 /// Policy refused: the request would exceed the allowance.
35 BudgetExceeded,
36 /// The allocator refused, surfaced via `try_reserve`.
37 AllocationFailed,
38}
39
40/// The extent a limit applies to.
41#[derive(Debug, Clone, Copy, PartialEq, Eq)]
42pub enum LimitScope {
43 /// The whole decode.
44 Global,
45 /// One expansion.
46 PerExpand,
47}
48
49/// An offset qualified by its address space.
50#[derive(Debug, Clone, Copy, PartialEq, Eq)]
51pub struct SourceLocation {
52 /// The space the offset indexes.
53 pub space: SpaceId,
54 /// The absolute offset within that space.
55 pub offset: u64,
56}
57
58/// Allocation-free context attached to a failure.
59#[derive(Debug, Clone, Copy, PartialEq, Eq)]
60pub struct ErrorContext {
61 /// The operation that failed, as a static label.
62 pub operation: &'static str,
63 /// Where it failed, when a location is known.
64 pub location: Option<SourceLocation>,
65}
66
67/// A resource refusal.
68#[derive(Debug, Clone, Copy, PartialEq, Eq)]
69pub struct ResourceLimit {
70 /// The dimension that refused the request.
71 pub dimension: ResourceDimension,
72 /// Whether policy or the allocator refused.
73 pub reason: ResourceFailure,
74 /// The extent the limit applies to.
75 pub scope: LimitScope,
76 /// The allowance in force.
77 pub limit: u64,
78 /// The amount already charged before this request.
79 pub used: u64,
80 /// The saturating size of the request that failed.
81 pub additional: u64,
82 /// Static context for the failure.
83 pub context: ErrorContext,
84}