Add support for `poll_oneoff` calls which just sleep on a relative
timeout. This fixes a bug handling code compiled with WASI libc's `sleep`
family of functions, which call `poll_oneoff` with a `CLOCK_REALTIME`
timer, which wasn't previously implemented.
the fdstat of a dirfd needs to include both the file and dir rights in
the inheriting field.
The wasi-libc path_open bases the base rights of child directories off
the inheriting rights of the parent, so if we only put file rights in
there, opening a child directory will not have any directory operations
permitted.
Fixes https://github.com/bytecodealliance/wasmtime/issues/2638
Previously, `fd_readdir` was truncating directory entry names based on the
calculation of `min(name_len, buf_len - bufused)`, but `bufused` was not being
updated after writing in the `dirent` structure to the buffer.
This allowed `bufused` to be incremented beyond `buf_len` and returned as the
number of bytes written to the buffer, which is invalid.
This fix adjusts `bufused` when the buffer is written to for the `dirent` so
that name truncation happens as expected.
Fixes#2618.
`fd_readdir` returns a "bufused" value, which indicates the number of
bytes read into the buffer. WASI libc expects this value to be equal
to the size of the buffer if the end of the directory has not yet
been scanned.
Previously, wasi-common's `fd_readdir` was writing as many complete
entries as it could fit and then stopping, but this meant it was
returning size less than the buffer size even when the directory had
more entries. This patch makes it continue writing up until the end
of the buffer, and return that number of bytes, to let WASI libc
know that there's more to be read.
Fixes#2493.
This commit deletes the old `snapshot_0` implementation of wasi-common,
along with the `wig` crate that was used to generate bindings for it.
This then reimplements `snapshot_0` in terms of
`wasi_snapshot_preview1`. There were very few changes between the two
snapshots:
* The `nlink` field of `FileStat` was increased from 32 to 64 bits.
* The `set` field of `whence` was reordered.
* Clock subscriptions in polling dropped their redundant userdata field.
This makes all of the syscalls relatively straightforward to simply
delegate to the next snapshot's implementation. Some trickery happens to
avoid extra cost when dealing with iovecs, but since the memory layout
of iovecs remained the same this should still work.
Now that `snapshot_0` is using wiggle we simply have a trait to
implement, and that's implemented for the same `WasiCtx` that has the
`wasi_snapshot_preview1` trait implemented for it as well. While this
theoretically means that you could share the file descriptor table
between the two snapshots that's not supported in the generated bindings
just yet. A separate `WasiCtx` will be created for each WASI module.
tracing is already the dep that wiggle uses.
I used tracing structured arguments wherever I could, but I skipped over
it in all of the snapshot_0 code, because I'm going to delete that code
and replace it with wiggle-based stuff real soon.
* Revert fstatat on *nix and test symlinks in path_filestat calls
This commit effectively reverts too eager refactoring on my part which
resulted in incorrect `path_filestat_{get, set_times}` behaviour on
*nix hosts. In the presence of symlinks, neither of the calls would
work properly.
In order to shield ourselves from similar errors in the future, I've
augmented the `path_filestat` test cases with symlink checks as well.
* Pass appropriate flags to fstatat and utimensat
* Fix formatting
* Fix Windows build
* Expand final symlinks if follow is set on Windows
* Fix formatting
* Do not follow symlinks unless specified on Windows
* Update comments and restart CI
* Skip testing volatile atim field
