This rather large commit adds/fixes missing WASI functionality
in `libstd` needed to pass the `libstd` tests. As such, now by
default tests targeting `wasm32-wasi` target are enabled in
`test/tests.zig` module. However, they can be disabled by passing
the `-Dskip-wasi=true` flag when invoking the `zig build test`
command. When the flag is set to `false`, i.e., when WASI tests are
included, `wasmtime` with `--dir=.` is used as the default testing
command.
Since the majority of `libstd` tests were relying on `fs.cwd()`
call to get current working directory handle wrapped in `Dir`
struct, in order to make the tests WASI-friendly, `fs.cwd()`
call was replaced with `testing.getTestDir()` function which
resolved to either `fs.cwd()` for non-WASI targets, or tries to
fetch the preopen list from the WASI runtime and extract a
preopen for '.' path.
The summary of changes introduced by this commit:
* implement `Dir.makeDir` and `Dir.openDir` targeting WASI
* implement `Dir.deleteFile` and `Dir.deleteDir` targeting WASI
* fix `os.close` and map errors in `unlinkat`
* move WASI-specific `mkdirat` and `unlinkat` from `std.fs.wasi`
to `std.os` module
* implement `lseek_{SET, CUR, END}` targeting WASI
* implement `futimens` targeting WASI
* implement `ftruncate` targeting WASI
* implement `readv`, `writev`, `pread{v}`, `pwrite{v}` targeting WASI
* make sure ANSI escape codes are _not_ used in stderr or stdout
in WASI, as WASI always sanitizes stderr, and sanitizes stdout if
fd is a TTY
* fix specifying WASI rights when opening/creating files/dirs
* tweak `AtomicFile` to be WASI-compatible
* implement `os.renameatWasi` for WASI-compliant `os.renameat` function
* implement sleep() targeting WASI
* fix `process.getEnvMap` targeting WASI
Remove `std.fs.deleteTree`. Callers instead should use
`std.fs.cwd().deleteTree`.
Add `std.fs.deleteTreeAbsolute` for when the caller has an absolute
path.
* remove deprecated `std.fs.Dir` APIs
* `std.fs.Dir.openDir` now takes a options struct with bool fields for
`access_sub_paths` and `iterate`. It's now much more clear how
opening directories works.
* fixed the std lib and various zig code calling the wrong openDir
function.
* the runtime safety check for dir flags is removed in favor of the
cheaper option of putting a comment on the same line as handling
EBADF / ACCESS_DENIED, since that will show up in stack traces.
Previously the zig build system incorrectly assumed that the only build
artifact was a binary. Now, when you enable the cache, only the output
dir is printed to stdout, and the zig build system iterates over the
files in that directory, copying them to the output directory.
To support this change:
* Add `std.os.renameat`, `std.os.renameatZ`, and `std.os.renameatW`.
* Fix `std.os.linux.renameat` not compiling due to typos.
* Deprecate `std.fs.updateFile` and `std.fs.updateFileMode`.
* Add `std.fs.Dir.updateFile`, which supports using open directory
handles for both the source and destination paths, as well as an
options parameter which allows overriding the mode.
* Update `std.fs.AtomicFile` to support operating based on an open
directory handle. Instead of `std.fs.AtomicFile.init`, use
`std.fs.Dir.atomicFile`.
* `std.fs.AtomicFile` deinit() better handles the situation when the
rename fails but the temporary file still exists, by still
attempting to remove the temporary file.
* `std.fs.Dir.openFileWindows` is moved to `std.os.windows.OpenFileW`.
* `std.os.RenameError` gains the error codes `NoDevice`,
`SharingViolation`, and `PipeBusy` which have been observed from
Windows.
Closes#4733
