Mercurial > public > mercurial-scm > hg

annotate rust/hg-cpython/src/pybytes_deref.rs @ 48674:f7086f6173f8 stable

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
dirstate-v2: rename the configuration to enable the format The rename of the old experimental name was overlooked before the 6.0 release. We rename everything to use the new name (and keep the released name as an alias for compatibility). Differential Revision: https://phab.mercurial-scm.org/D12129
author Pierre-Yves David <pierre-yves.david@octobus.net>
date Tue, 01 Feb 2022 16:36:20 +0100
parents 4afd6cc447b9
children be3b545c5cff
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
47953
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
1 use cpython::{PyBytes, Python};
47954
4afd6cc447b9 rust: Make OwningDirstateMap generic and move it into hg-core
Simon Sapin <simon.sapin@octobus.net>
parents: 47953
diff changeset
2 use stable_deref_trait::StableDeref;
47953
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
3
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
4 /// Safe abstraction over a `PyBytes` together with the `&[u8]` slice
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
5 /// that borrows it. Implements `Deref<Target = [u8]>`.
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
6 ///
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
7 /// Calling `PyBytes::data` requires a GIL marker but we want to access the
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
8 /// data in a thread that (ideally) does not need to acquire the GIL.
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
9 /// This type allows separating the call an the use.
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
10 ///
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
11 /// It also enables using a (wrapped) `PyBytes` in GIL-unaware generic code.
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
12 pub struct PyBytesDeref {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
13 #[allow(unused)]
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
14 keep_alive: PyBytes,
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
15
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
16 /// Borrows the buffer inside `self.keep_alive`,
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
17 /// but the borrow-checker cannot express self-referential structs.
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
18 data: *const [u8],
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
19 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
20
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
21 impl PyBytesDeref {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
22 pub fn new(py: Python, bytes: PyBytes) -> Self {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
23 Self {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
24 data: bytes.data(py),
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
25 keep_alive: bytes,
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
26 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
27 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
28
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
29 pub fn unwrap(self) -> PyBytes {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
30 self.keep_alive
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
31 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
32 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
33
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
34 impl std::ops::Deref for PyBytesDeref {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
35 type Target = [u8];
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
36
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
37 fn deref(&self) -> &[u8] {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
38 // Safety: the raw pointer is valid as long as the PyBytes is still
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
39 // alive, and the returned slice borrows `self`.
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
40 unsafe { &*self.data }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
41 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
42 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
43
47954
4afd6cc447b9 rust: Make OwningDirstateMap generic and move it into hg-core
Simon Sapin <simon.sapin@octobus.net>
parents: 47953
diff changeset
44 unsafe impl StableDeref for PyBytesDeref {}
4afd6cc447b9 rust: Make OwningDirstateMap generic and move it into hg-core
Simon Sapin <simon.sapin@octobus.net>
parents: 47953
diff changeset
45
47953
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
46 fn require_send<T: Send>() {}
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
47
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
48 #[allow(unused)]
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
49 fn static_assert_pybytes_is_send() {
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
50 require_send::<PyBytes>;
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
51 }
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
52
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
53 // Safety: PyBytes is Send. Raw pointers are not by default,
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
54 // but here sending one to another thread is fine since we ensure it stays
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
55 // valid.
8f031a274cd6 rust: Move PyBytesWithData out of copy-tracing code
Simon Sapin <simon.sapin@octobus.net>
parents:
diff changeset
56 unsafe impl Send for PyBytesDeref {}