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.
This commit updates the WASI imports to use `wasi_snapshot_preview1`
instead of the old `wasi_unstable`. There are some minor ABI
differences between the two, however, the main motivator for using
the latest "stable" snapshot (aka preview1) is that, at least in
Wasmtime, there has been a lot of improvement work put into preview1
and unfortunately I might add, the improvements were not (in full)
backported to `wasi_unstable` snapshot.
Also, this commit removes the optional bound on the pointer to
`environ_get` syscall.
