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use super::*;
fn selected(
backwards: bool,
property: u32,
index: Option<u32>,
sequences: Option<&[u64]>,
) -> PreparedReadRange<'static> {
PreparedReadRange {
request: ReadRangeRequest {
object_identifier: ObjectIdentifier::new(ObjectType::TREND_LOG, 1).unwrap(),
property_identifier: PropertyIdentifier::from_raw(property),
property_array_index: index,
range: Some(RangeSpec::ByPosition {
reference_index: if backwards { 3 } else { 1 },
count: if backwards { -3 } else { 3 },
}),
},
items: RangeItems::Values(values()),
selection: SignedRangeSelection::from_range(3, 0..3),
first_sequence_number: sequences.map(|s| s[0]),
identities: sequences.map(|s| {
LogIdentities::Listed(
s.iter()
.map(|seq| {
LogRecordIdentity::new(
*seq,
Date {
year: 126,
month: 9,
day: 1,
day_of_week: 2,
},
Time {
hour: 1,
minute: 0,
second: 0,
hundredths: 0,
},
)
.unwrap()
})
.collect(),
)
}),
}
}
fn values() -> Vec<PropertyValue> {
vec![
PropertyValue::Unsigned(1),
PropertyValue::Unsigned(2),
PropertyValue::Unsigned(3),
]
}
#[test]
fn bounded_encode_calls_defer_failures_and_preserve_output_on_current_error() {
for backwards in [false, true] {
let selected = selected(backwards, 131, None, None);
for (cap, byte_cap, failure_at, expected_calls, success) in [
(1, 100, 2, 1, true), // next item deferred, never encoded
(3, 16, 3, 2, true), // one fitting item, one oversized trial, third untouched
(3, 100, 2, 2, false), // error after accepted scratch, not a successful page
(3, 13, 1, 0, false), // even empty header cannot fit
(3, 15, 3, 1, false), // first item cannot fit; no empty MORE_ITEMS loop
] {
let mut output = BytesMut::from(&b"old"[..]);
let mut calls = 0;
let mut order = Vec::new();
let result = append_page_with(
&selected,
&mut output,
ReadRangeBudget {
max_returned_items: cap,
max_service_ack_bytes: byte_cap,
},
|buf, item| {
calls += 1;
order.push(item.clone());
if calls == failure_at {
return Err(Error::Encoding("current item".into()));
}
encode_property_value(buf, item)
},
);
assert_eq!(calls, expected_calls);
assert_eq!(result.is_ok(), success);
if success {
let ack = ReadRangeAck::decode(&output[3..]).unwrap();
assert_eq!(ack.item_count, 1);
assert_eq!(ack.result_flags, (!backwards, backwards, true));
} else {
assert_eq!(&output[..], b"old");
if calls == failure_at {
assert!(matches!(
result,
Err(ReadRangeFailure::Service(Error::Encoding(_)))
));
} else {
assert!(matches!(result, Err(ReadRangeFailure::Bytes)));
}
}
if calls > 0 {
assert_eq!(order[0], values()[if backwards { 2 } else { 0 }]);
}
}
}
}
#[test]
fn exact_envelopes_include_property_index_and_changing_first_sequence_widths() {
for property in [255, 256, 65535, 65536, u32::MAX] {
for index in [
None,
Some(255),
Some(256),
Some(65535),
Some(65536),
Some(u32::MAX),
] {
// Audit Log identities pass 2^32 - 1, so the last set needs
// five- and eight-octet first sequence numbers.
for sequences in [
[u64::from(u32::MAX), 255, 256],
[1, 65536, 65535],
[256, 1, u64::from(u32::MAX)],
[1 << 32, 1, u64::MAX],
] {
for backwards in [false, true] {
let selected = selected(backwards, property, index, Some(&sequences));
// Independent field-width arithmetic: OID=5, flags=3, count=2,
// opening/closing tags=2; unsigned/enumerated fields add tag+width,
// and a content longer than four octets adds one length octet.
let width =
|x: u64| (u64::BITS - x.leading_zeros()).div_ceil(8).max(1) as usize;
let tagged = |x: u64| width(x) + if width(x) > 4 { 2 } else { 1 };
let fixed = 12
+ tagged(u64::from(property))
+ index.map_or(0, |i| tagged(u64::from(i)));
for n in [1, 2, 3] {
let first = if backwards { 3 - n } else { 0 };
let bytes = fixed + n * 2 + tagged(sequences[first]);
let mut output = BytesMut::new();
let result = append_page_with(
&selected,
&mut output,
ReadRangeBudget {
max_returned_items: n,
max_service_ack_bytes: bytes,
},
encode_property_value,
);
// A later narrower identity must not rescue a page whose
// directional first item (or earlier candidate) did not fit.
let first_over = (1..=n).find(|m| {
let start = if backwards { 3 - m } else { 0 };
fixed + m * 2 + tagged(sequences[start]) > bytes
});
if let Some(m) = first_over {
if m == 1 {
assert!(matches!(result, Err(ReadRangeFailure::Bytes)));
assert!(output.is_empty());
} else {
result.unwrap();
assert_eq!(
ReadRangeAck::decode(&output).unwrap().item_count,
(m - 1) as u32
);
}
continue;
}
result.unwrap();
assert_eq!(output.len(), bytes);
let ack = ReadRangeAck::decode(&output).unwrap();
assert_eq!(ack.first_sequence_number, Some(sequences[first]));
assert_eq!(ack.item_count, n as u32);
let mut expected = BytesMut::new();
for item in &values()[if backwards { 3 - n..3 } else { 0..n }] {
encode_property_value(&mut expected, item).unwrap();
}
assert_eq!(ack.item_data, expected);
let mut under = BytesMut::from(&b"old"[..]);
let result = append_page_with(
&selected,
&mut under,
ReadRangeBudget {
max_returned_items: n,
max_service_ack_bytes: bytes - 1,
},
encode_property_value,
);
if n == 1 {
assert!(matches!(result, Err(ReadRangeFailure::Bytes)));
assert_eq!(&under[..], b"old");
} else if result.is_ok() {
assert!(
ReadRangeAck::decode(&under[3..]).unwrap().item_count < n as u32
);
}
}
}
}
}
}
}