dope_core/driver/route/table/
borrows.rs

1use external::errors;
2use o3::depot::{
3    arena::slab::{self, external},
4    capacity,
5};
6use table::entries::{occupied, vacant};
7
8use crate::driver::{
9    route,
10    route::{indices, table, table::conn},
11};
12
13#[repr(transparent)]
14pub struct View<'a, T, Tag: route::Tag> {
15    pub(in crate::driver::route::table) inner: &'a table::Storage<T, Tag>,
16}
17
18impl<'a, T, Tag: route::Tag> View<'a, T, Tag> {
19    /// Returns the immutable extent admitted when this route table was allocated.
20    pub fn capacity(&self) -> table::Capacity {
21        table::Capacity(self.inner.capacity())
22    }
23
24    pub fn len(&self) -> capacity::Count {
25        self.inner.len()
26    }
27
28    /// Returns capacity minus the number of initialized values.
29    ///
30    /// Forgotten reservations are included, so this is an upper bound on
31    /// reservable slots. Reservation still reports `Full` or `IdentityExhausted`.
32    pub fn available(&self) -> capacity::Count {
33        let total = self.inner.capacity();
34        let occupied = self.inner.len();
35        capacity::Count::new(total.raw() - occupied.raw())
36    }
37
38    pub fn is_empty(&self) -> bool {
39        self.inner.is_empty()
40    }
41
42    pub fn next_generation(&self) -> Option<route::Epoch> {
43        self.inner.next_generation()
44    }
45
46    pub fn get(self, parts: table::Parts<Tag>) -> Option<&'a T> {
47        self.inner.get(parts.external())
48    }
49
50    pub fn contains(self, parts: table::Parts<Tag>) -> bool {
51        self.inner.get(parts.external()).is_some()
52    }
53
54    pub fn key_at(self, slot: indices::SlotIndex) -> Option<table::Key<Tag>> {
55        self.inner.key_at(slot.raw()).map(table::Key::new)
56    }
57}
58
59#[repr(transparent)]
60pub struct Access<'a, T, Tag: route::Tag>(
61    pub(in crate::driver::route::table) &'a mut table::Storage<T, Tag>,
62);
63
64impl<'a, T, Tag: route::Tag> Access<'a, T, Tag> {
65    pub fn advance_to(self, floor: Option<route::Epoch>) {
66        self.0.advance_to(floor);
67    }
68
69    pub fn get(self, parts: table::Parts<Tag>) -> Option<&'a mut T> {
70        self.0.get_mut(parts.external())
71    }
72
73    pub fn occupied(self, parts: table::Parts<Tag>) -> Option<occupied::Entry<'a, T, Tag>> {
74        self.0.occupied(parts.external()).map(occupied::Entry)
75    }
76
77    pub fn try_occupied(
78        self,
79        parts: table::Parts<Tag>,
80    ) -> Result<occupied::Entry<'a, T, Tag>, errors::Lookup<route::Epoch, Tag>> {
81        let entry = self.0.try_occupied(parts.external())?;
82        Ok(occupied::Entry(entry))
83    }
84
85    /// Borrows the current owner directly from this table's physical slot.
86    pub fn at(self, index: indices::SlotIndex) -> Option<occupied::Entry<'a, T, Tag>> {
87        self.0.occupied_at(index.raw()).map(occupied::Entry)
88    }
89}
90
91#[repr(transparent)]
92pub struct Grant<'a, T, Tag: route::Tag>(
93    external::Grant<'a, T, route::Epoch, Tag, { u32::MAX }, { table::PARTITIONS }>,
94);
95
96impl<'a, T, Tag: route::Tag> Grant<'a, T, Tag> {
97    pub fn reserve(self) -> vacant::Entry<'a, T, Tag> {
98        vacant::Entry {
99            inner: self.0.reserve(),
100        }
101    }
102}
103
104#[repr(transparent)]
105pub struct Vacancy<'a, T, Tag: route::Tag>(
106    pub(in crate::driver::route::table) &'a mut table::Storage<T, Tag>,
107);
108
109impl<'a, T, Tag: route::Tag> Vacancy<'a, T, Tag> {
110    pub fn try_reserve(self) -> Result<vacant::Entry<'a, T, Tag>, slab::Vacancy> {
111        let grant = self.0.try_grant()?;
112        Ok(vacant::Entry {
113            inner: grant.reserve(),
114        })
115    }
116
117    pub fn try_head(self, capacity: conn::Capacity) -> Result<Grant<'a, T, Tag>, slab::Vacancy> {
118        self.0.try_grant_in(0..capacity.count().get()).map(Grant)
119    }
120
121    /// Selects physical capacity before identity, excluding one held slot.
122    pub fn try_except(
123        self,
124        capacity: conn::Capacity,
125        excluded: indices::SlotIndex,
126    ) -> Result<Grant<'a, T, Tag>, slab::Vacancy> {
127        self.0
128            .try_except(0..capacity.count().get(), excluded.raw())
129            .map(Grant)
130    }
131}
dope_core/driver/route/table/borrows.rs

dope_core/driver/route/table/
borrows.rs
