Previously, the path and preopens helpers were prototyped in `std.os.wasi`
module, but since they are higher-level abstraction over wasi, they belong in
`std.fs.wasi` module.
This commit removes `std.os.openatWasi` function, and renames it to
`std.os.wasi.openat`. Additionally, the added `PreopenList.findByPath`
method allows querying the list for a matching preopen by path.
This commit refactors `std.os.wasi.resolve_preopen` into a (higher-level)
`std.os.wasi.getPreopens` funtion which returns a slice with _all_
preopens at any given time. This fn allows the WASI module to
inquire at any given time for all preopens provided by the runtime.
This commit also makes `cwd()` a compile error on WASI.
This commit adds WASI specific impl of `std.fs.cwd()` in which we
emulate the `cwd` behaviour by inquiring the runtime for a "."
preopen if available. This is OK for simple relative ops, but will
not work for any ops which require absolute paths.
It seems that `std.os.openZ` is too POSIX-specific, so I think it
should not be a point of entry for WASI `open` call. I figure
WASI should be treated as a separate "os" that's _not_ POSIX
especially given the incoming changes in the ephemeral snapshot.
According to documentation ETIMEDOUT (110) is a valid error code for the read function. I just had my long-running (been running for about 7 weeks) network program crash because it did not handle the ETIMEDOUT error code from "read".
Before it was possible for .intended_io_mode = .blocking,
.capable_io_mode = .evented, and then the implementation would put a
request on the fs thread, which is the wrong behavior. Now it always
calls the appropriate WriteFile/ReadFile function, passing the intended
io mode directly as a parameter.
This makes the behavior tests pass on Windows with --test-evented-io.
Now there are 3 types:
* std.math.big.int.Const
- the memory is immutable, only stores limbs and is_positive
- all methods operating on constant data go here
* std.math.big.int.Mutable
- the memory is mutable, stores capacity in addition to limbs and
is_positive
- methods here have some Mutable parameters and some Const
parameters. These methods expect callers to pre-calculate the
amount of resources required, and asserts that the resources are
available.
* std.math.big.int.Managed
- the memory is mutable and additionally stores an allocator.
- methods here perform the resource calculations for the programmer.
- this is the high level abstraction from before
Each of these 3 types can be converted to the other ones.
You can see the use case for this in the self-hosted compiler, where we
only store limbs, and construct the big ints as needed.
This gets rid of the hack where the allocator was optional and the
notion of "fixed" versions of the struct. Such things are now modeled
with the `big.int.Const` type.
`wasi_snapshot_preview1` introduced a couple of ABI changes. This
commit fast-forwards the types and consts defined in `std.os.bits.wasi`
to match those changes.
