Currently, the use of the downcast method means that you have to use one
of the hard-coded types. But Enarx needs to define its own `WasiFile`
implementations. This works fine, except the resulting files cannot be
used in poll because they aren't part of the hard-coded list.
Replace this with an accessor method for the pollable type in
`WasiFile`. Because we provide a default implementation of the method
and manually implement it on all the hard-coded types, this is backwards
compatible.
Signed-off-by: Nathaniel McCallum <nathaniel@profian.com>
1. This makes it easier for implementors to deal with internal APIs.
2. This matches the signatures of the WASI Snapshot traits.
Although it is likely true that these methods would have to become
immutable in order to implement threading efficiently, threading will
impact a large number of existing traits. So this change is practical
for now with an already-unavoidable change required for threading.
Signed-off-by: Nathaniel McCallum <nathaniel@profian.com>
With the addition of `sock_accept()` in `wasi-0.11.0`, wasmtime can now
implement basic networking for pre-opened sockets.
For Windows `AsHandle` was replaced with `AsRawHandleOrSocket` to cope
with the duality of Handles and Sockets.
For Unix a `wasi_cap_std_sync::net::Socket` enum was created to handle
the {Tcp,Unix}{Listener,Stream} more efficiently in
`WasiCtxBuilder::preopened_socket()`.
The addition of that many `WasiFile` implementors was mainly necessary,
because of the difference in the `num_ready_bytes()` function.
A known issue is Windows now busy polling on sockets, because except
for `stdin`, nothing is querying the status of windows handles/sockets.
Another know issue on Windows, is that there is no crate providing
support for `fcntl(fd, F_GETFL, 0)` on a socket.
Signed-off-by: Harald Hoyer <harald@profian.com>
WASI doesn't have an `isatty` ioctl or syscall, so wasi-libc's `isatty`
implementation uses the file descriptor type and rights to determine if
the file descriptor is likely to be a tty. The real fix here will be to
add an `isatty` call to WASI. But for now, have Wasmtime set the
filetype and rights for file descriptors so that wasi-libc's `isatty`
works as expected.
Implement Wasmtime's new API as designed by RFC 11. This is quite a large commit which has had lots of discussion externally, so for more information it's best to read the RFC thread and the PR thread.
