`std.os.getFdPath` is very platform-specific and can be used to query
the OS for a canonical path to a file handle. Currently supported hosts
are Linux, macOS and Windows.
`std.fs.Dir.realpath` (and null-terminated, plus WTF16 versions) are
similar to `std.os.realpath`, however, they resolve a path wrt to this
`Dir` instance.
If the input pathname argument turns out to be an absolute path, this
function reverts to calling `realpath` on that pathname completely
ignoring this `Dir`.
This commit reimagines `std.os.windows.GetFinalPathNameByHandle`
using `DeviceIoControl` to query the OS mount manager for the DOS
(symlink) paths for the given NT volume name. In particular,
it uses `IOCTL_MOUNTMGR_QUERY_POINTS` ioctl opcode to query the
manager for the available moount points.
This commit proposes an initial draft of `GetPathNameByHandle` function
which wraps NT syscalls and strives to emulate (currently only
partially) the `kernel32.GetFinalPathNameByHandleW` function.
This way, we can remove more `kernel32` calls such as `RemoveDirectoryW`
or `DeleteFileW`, and use `std.os.windows.DeleteFile` instead which
is purely NT-based.
Replace them with `std.os.windows.OpenFile` instead. To allow
creation/opening of directories, `std.os.windows.OpenFileOptions`
now features a `.expect_dir: bool` member which is meant to emualate
POSIX's `O_DIRECTORY` flag.
Otherwise, the behaviour can lead to unexpected results, resulting
in removing an entire tree that's not necessarily under the root.
Furthermore, this change is needed if are to properly handle dir
symlinks on Windows. Without explicitly requiring that a directory
or file is opened with `FILE_OPEN_REPARSE_POINT`, Windows automatically
dereferences all symlinks along the way. This commit adds another
option to `OpenDirOptions`, namely `.no_follow`, which defaults to
`false` and can be used to specifically open a directory symlink on
Windows or call `openat` with `O_NOFOLLOW` flag in POSIX.
This way `std.fs.symlinkAbsolute` becomes cross-platform and we can
legally include `SymlinkFlags` as an argument that's only used on
Windows. Also, now `std.os.symlink` generates a compile error on
Windows with a message to instead use `std.os.windows.CreateSymbolicLink`.
Finally, this PR also reshuffles the tests between `std.os.test` and
`std.fs.test`.
This is direct result of review comments left by andrewrk and
daurnimator. It makes sense to map `ENOTCAPABLE` into a more generic
`error.AccessDenied`.
This commit adds `error.NotCapable` enum value and makes sure that
every applicable WASI syscall that can return `ENOTCAPABLE` errno
remaps it to `error.NotCapable.
Also, add more informative `@compileError` in a few `std.os` functions
that would otherwise yield a cryptic compile error when targeting
WASI. Finally, enhance docs in a few places and add test case for
`fstatat`.
Adds Windows stub (still needs to be implemented on Windows),
adds WASI implementation, adds unit test testing basic chain of
ops: create file -> symlink -> readlink.
* improve docs
* add TODO comments for things that don't have open issues
* remove redundant namespacing of struct fields
* guard against ioctl returning EINTR
* remove the general std.os.ioctl function in favor of the specific
ioctl_SIOCGIFINDEX function. This allows us to have a more precise
error set, and more type-safe API.
Andrew Kelley
Luna
Jakub Konka
Maciej Walczak
Vexu
Ryan Liptak