This changes file descriptors from uint32 to int32 and the
corresponding file table to reject negative values. This ensures
invalid values aren't mistaken for very large descriptor entries, which
can use a lot of memory as the table implementation isn't designed to
be sparse.
See https://pubs.opengroup.org/onlinepubs/9699919799/functions/dirfd.html#tag_16_90
Signed-off-by: Adrian Cole <adrian@tetrate.io>
The PR introduces the `platform.Select()` API, wrapping `select(2)` on POSIX and emulated in some cases on Windows. RATIONALE.md contains a full explanation of the approach followed in `poll_oneoff` to handle Stdin and the other types of file descriptors, and the clock subscriptions.
It also introduces an abstraction (`StdioFilePoller`) to allow the simulation of different scenarios (waiting for input, input ready, timeout expired, etc.) when unit-testing interactive input.
This closes#1317.
Signed-off-by: Edoardo Vacchi <evacchi@users.noreply.github.com>
Ensure that stdio device modes are consistent with the given
file descriptors by stat'ing, instead of returning mocks.
* Use `Stat()` on `poll_oneoff()` too, instead of `IsTerminal()`,
thus avoiding a useless syscall.
* Delete leftover type decl `fileModeStat`.
* Remove IsPlatform()
* Propagate error when Stat() fails
Signed-off-by: Edoardo Vacchi <evacchi@users.noreply.github.com>
This forces all syscall functions, notably filesystem, to return numeric
codes as opposed to mapping in two different areas. The result of this
change is better consolidation in call sites of `sysfs.FS`, while
further refactoring is needed to address consolidation of file errors.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
wasi-testsuite changed its mind on pre-open WebAssembly/wasi-testsuite#66
they also now explicitly forbid paths being passed in with a leading slash. Even when the config bug on WebAssembly/wasi-testsuite#67 is finished, this requires discussion if we want to EPERM on that.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This forces all syscall functions, notably filesystem, to return numeric
codes as opposed to mapping in two different areas. The result of this
change is better consolidation in call sites of `sysfs.FS`, while
further refactoring is needed to address consolidation of file errors.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This returns stat as a value instead of a pointer param. This is both
more efficient and faster. It is also more efficient than returning a
pointer to a stat.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
We formerly cached only the directory type, to avoid re-stat'ing the
same directory many times. Since we are there, we can also cache the
inode, which is strictly required by wasi and costly to fetch. Note:
this only affects the directory: its contents still need a potential
fan-out of stats which will be handled in another change.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
wasi_snapshot_preview1 recently requires fd_readdir to return actual
inode values. On zero, wasi-libc will call fdstat to retrieve them.
This introduces our own `platform.Dirent` type and `Readdir` function
which a later change will allow fetching of inodes.
See https://github.com/WebAssembly/wasi-libc/pull/345
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This centralizes filestat logic by making our own `Stat_t` similar to
`syscall.Stat_t`. This exposes utilities in the platform package and
adds a new function `FS.Stat` which avoids having to use `fs.File` to
get the same info. Doing so at the FS abstraction allows us to optimize
how it is implemented internally using portable means (e.g.
`os.StatFile`) or OS-specific means where necessary, e.g. in windows.
This also ensures `platform.OpenFile` returns syscall.Errno and
centralizes error checking with a new `require.EqualErrno` test.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
