Crate wasi_cap_std_sync
source · [−]Expand description
The wasi-cap-std-sync
crate provides impl of WasiFile
and WasiDir
in
terms of cap_std::fs::{File, Dir}
. These types provide sandboxed access
to the local filesystem on both Unix and Windows.
All syscalls are hidden behind the cap-std
hierarchy, with the lone
exception of the sched
implementation, which is provided for both unix
and windows in separate modules.
Any wasi_common::{WasiCtx, WasiCtxBuilder}
is interoperable with the
wasi-cap-std-sync
crate. However, for convenience, wasi-cap-std-sync
provides its own WasiCtxBuilder
that hooks up to all of the crate’s
components, i.e. it fills in all of the arguments to
WasiCtx::builder(...)
, presents preopen_dir
in terms of
cap_std::fs::Dir
, and provides convenience methods for inheriting the
parent process’s stdio, args, and env.
For the convenience of consumers, cap_std::fs::Dir
is re-exported from
this crate. This saves consumers tracking an additional dep on the exact
version of cap_std used by this crate, if they want to avoid it.
The only place we expect to run into long-term compatibility issues
between wasi-cap-std-sync
and the other impl crates that will come later
is in the Sched
abstraction. Once we can build an async scheduler based
on Rust Future
s, async impls will be able to interoperate, but the
synchronous scheduler depends on downcasting the WasiFile
type down to
concrete types it knows about (which in turn impl AsFd
for passing to
unix poll
, or the analogous traits on windows).
Why is this impl suffixed with -sync
? Because async
is coming soon!
The async impl may end up depending on tokio or other relatively heavy
deps, so we will retain a sync implementation so that wasi-common users
have an option of not pulling in an async runtime.
Re-exports
pub use clocks::clocks_ctx;
pub use sched::sched_ctx;
Modules
Structs
A reference to an open directory on a filesystem.
A TCP socket server, listening for connections.
Functions
Return an AmbientAuthority
value, which allows use of functions that
include an AmbientAuthority
argument.