This allows you to specify the memory scope amongst existing logging scopes, both in API and the CLI.
e.g for the CLI.
```bash
$ wazero run --hostlogging=memory,filesystem --mount=.:/:ro cat.wasm
```
e.g. for Go
```go
loggingCtx := context.WithValue(testCtx, experimental.FunctionListenerFactoryKey{},
logging.NewHostLoggingListenerFactory(&log, logging.LogScopeMemory|logging.LogScopeFilesystem))
```
This is helpful for emscripten and gojs which have memory reset
callbacks. This will be much more interesting once #1075 is implemented.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This allows you to specify the exit scope amongst existing logging scopes, both in API and the CLI.
e.g for the CLI.
```bash
$ wazero run --hostlogging=exit,filesystem --mount=.:/:ro cat.wasm
```
e.g. for Go
```go
loggingCtx := context.WithValue(testCtx, experimental.FunctionListenerFactoryKey{},
logging.NewHostLoggingListenerFactory(&log, logging.LogScopeExit|logging.LogScopeFilesystem))
```
This is helpful to know if the wasm called exit or if it exited
implicitly. This is one of the few host functions that exists in three
places: assemblyscript, gojs and wasi.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This allows the CLI to use `-hostlogging=filesystem,poll` instead of or
in addition to multiple flags.
This also makes the parameter loggers more debugable by using pointer
receivers. When they are copied, the field names end up garbage in the
debugger.
Finally, this fixes a glitch where we used GOOS=js where we thought we
were using WASI (in cmd tests).
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This allows you to specify the poll scope amongst existing logging scopes, both in API and the CLI.
e.g for the CLI.
```bash
$ wazero run --hostlogging=poll --hostlogging=filesystem --mount=.:/:ro cat.wasm
```
e.g. for Go
```go
loggingCtx := context.WithValue(testCtx, experimental.FunctionListenerFactoryKey{},
logging.NewHostLoggingListenerFactory(&log, logging.LogScopePoll|logging.LogScopeFilesystem))
```
This is particularly helpful to understand side-effects of GC. For
example, in `GOOS=js` GC will trigger events and these have been tricky
to troubleshoot in the past.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This is to avoid a collision with an emerging wasi-crypto. They will
have both wasi-random and wasi-crypto
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This allows you to specify multiple logging scopes, both in API and the CLI.
e.g for the CLI.
```bash
$ wazero run --hostlogging=crypto --hostlogging=filesystem --mount=.:/:ro cat.wasm
```
e.g. for Go
```go
loggingCtx := context.WithValue(testCtx, experimental.FunctionListenerFactoryKey{},
logging.NewHostLoggingListenerFactory(&log, logging.LogScopeCrypto|logging.LogScopeFilesystem))
```
Signed-off-by: Edoardo Vacchi <evacchi@users.noreply.github.com>
Signed-off-by: Adrian Cole <adrian@tetrate.io>
Co-authored-by: Adrian Cole <adrian@tetrate.io>
This changes the logic inside CompositeFS in preparation of re-using the
user-provided input paths for pre-open paths. The main change here is
retaining original insertion order until runtime, then just iterating
backwards then.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This adds a new top-level type FSConfig, which is configured via
`ModuleConfig.WithFSConfig(fcfg)`. This implements read-only and
read-write directory mounts, something not formally supported before. It
also implements `WithFS` which adapts a normal `fs.FS`. For convenience,
we retain the old `ModuleConfig.WithFS` signature so as to not affect
existing users much. A new configuration for our emerging raw
filesystem, `FSConfig.WithSysfs()` will happen later without breaking
this API.
Here's an example:
```
moduleConfig = wazero.NewModuleConfig().
// Make the current directory read-only accessible to the guest.
WithReadOnlyDirMount(".", "/")
// Make "/tmp/wasm" accessible to the guest as "/tmp".
WithDirMount("/tmp/wasm", "/tmp")
```
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This decouples sysfs.FS from fs.FS by introducing a temporary type
FSHolder, which will be removed when we top-level FSConfig (shortly).
This further reduces complexity by consolidating guest path
configuration into the only type that uses it: CompositeFS.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
It will help for us to rename earlier vs later, and syscallfs will be
laborious, especially after we introduce an FSConfig type and need to
declare a method name that differentiates from normal fs.FS. e.g. WithFS
vs WithSysFS reads nicer than WithSyscallFS, and meanwhile sys is
already a public package.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This adds syntax needed for wasi-testsuite, which mounts a path like
below without mounting anything for "/".
```
-mount=./tests/c/testsuite/fs-tests.dir:/fs-tests.dir
```
Basically, this creates a virtual root path with fake stat.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This reduces some boilerplate by extracting UnimplementedFS from the
existing FS implementations, such that it returns ENOSYS. This also
removes inconsistency where some methods on FS returned syscall.Errno
and others PathError.
Note: this doesn't get rid of all PathError, yet. We still need to
create a syscallfs.File type which would be able to do that. This is
just one preliminary cleanup before refactoring out the `fs.FS`
embedding from `syscallfs.DS`.
P.S. naming convention is arbitrary, so I took UnimplementedXXX from
grpc. This pattern is used a lot of places, also proxy-wasm-go-sdk, e.g.
`DefaultVMContext`.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This prepares for pseudo-root when the CLI doesn't provide one by
improving the error messages in general, as well being consistent about
parameter order.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This implements stat device and inode for WASI and GOOS=js, though it
does not implement the host side for windows, yet. Doing windows
requires plumbing as the values needed aren't exposed in Go. When we
re-do the syscallfs file type to have a stat method, we can address that
glitch. Meanwhile, I can find no Go sourcebase that does any better,
though the closest is the implementation details of os.SameFile.
I verified this with wasi-testsuite which now passes all but 1 case
which is unrelated (we haven't yet implemented `lseek`).
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This implements WriterAtOffset, which supports WASI `fd_pwrite` and gojs
`fs.write` with offset, which is used to implement `syscall.Pwrite`.
I confirmed this passes the corresponding test in wasi-testsuite as
well.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This extracts a utility `syscallfs.ReaderAtOffset()` to allow WASI and
gojs to re-use the same logic to implement `syscall.Pread`.
What's different than before is that if WASI passes multiple iovecs an
emulated `ReaderAt` will seek to the read position on each call to
`Read` vs once per loop. This was a design decision to keep the call
sites compatible between files that implement ReaderAt and those that
emulate them with Seeker (e.g. avoid the need for a read-scoped closer/
defer function). The main use case for emulation is `embed.file`, whose
seek function is cheap, so there's little performance impact to this.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This rewrites compositeFS to syscallfs.FS following wasi-sdk preopen
rules. Notably, this allows use of read-only mounts now.
For example,
```bash
$ GOOS=js GOARCH=wasm bin/go test -c -o template.wasm text/template
$ wazero run -mount=src/text/template:/ -mount=/tmp:/tmp template.wasm -test.v
=== RUN TestExecute
--- PASS: TestExecute (0.07s)
--snip--
```
This is the first step to native WASI handling of multiple pre-opens.
After this change, it is still the case that there's only one pre-open
FD visible to wasm. A later change will make it possible for WASI to see
multiple pre-opens while `GOOS=js` which doesn't use preopens, remains
on a rootFS.
A future PR may need to add a CLI flag to disable escaping directories,
(e.g. make ../.. EINVAL), similar to `fs.FS` in Go. The simplest way to
allow this is to use a host-side RootFS even in WASI, and wrap that with
a `syscallfs` filename filter.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This works around a known glitch in windows where directory entry stat
doesn't match its corresponding file stat (namely times don't). It
consolidates more test files, in the process, to ensure we are more
likely to trigger issues like this earlier.
Future work will finish the last couple places where we still use go's
fstest.MapFS internally, as well introduce stat tests at the syscallfs
abstraction: right now, most tests are still only defined in WASI.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
Formerly, we introduced `wazero.Namespace` to help avoid module name or import conflicts while still sharing the runtime's compilation cache. Now that we've introduced `CompilationCache` `wazero.Namespace` is no longer necessary. By removing it, we reduce the conceptual load on end users as well internal complexity. Since most users don't use namespace, the change isn't very impactful.
Users who are only trying to avoid module name conflict can generate a name like below instead of using multiple runtimes:
```go
moduleName := fmt.Sprintf("%d", atomic.AddUint64(&m.instanceCounter, 1))
module, err := runtime.InstantiateModule(ctx, compiled, config.WithName(moduleName))
```
For `HostModuleBuilder` users, we no longer take `Namespace` as the last parameter of `Instantiate` method:
```diff
// log to the console.
_, err := r.NewHostModuleBuilder("env").
NewFunctionBuilder().WithFunc(logString).Export("log").
- Instantiate(ctx, r)
+ Instantiate(ctx)
if err != nil {
log.Panicln(err)
}
```
The following is an example diff a use of namespace can use to keep compilation cache while also ensuring their modules don't conflict:
```diff
func useMultipleRuntimes(ctx context.Context, cache) {
- r := wazero.NewRuntime(ctx)
+ cache := wazero.NewCompilationCache()
for i := 0; i < N; i++ {
- // Create a new namespace to instantiate modules into.
- ns := r.NewNamespace(ctx) // Note: this is closed when the Runtime is
+ r := wazero.NewRuntimeWithConfig(ctx, wazero.NewRuntimeConfig().WithCompilationCache(cache))
// Instantiate a new "env" module which exports a stateful function.
_, err := r.NewHostModuleBuilder("env").
```
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
@achille-roussel mentioned on chat that we have an accident waiting to
happen. This fixes it and backfills the missing test.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This introduces the new API wazero.Cache interface which can be passed to wazero.RuntimeConfig.
Users can configure this to share the underlying compilation cache across multiple wazero.Runtime.
And along the way, this deletes the experimental file cache API as it's replaced by this new API.
Signed-off-by: Takeshi Yoneda <takeshi@tetrate.io>
Co-authored-by: Crypt Keeper <64215+codefromthecrypt@users.noreply.github.com>
This consolidates test files and ensures our various implementations of
`syscallfs.FS` pass `fstest.TestFS`.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This adds FS.Path which holds the pre-open path currently only used in
WASI. It also fixes a TODO where we didn't know for sure if the FD
parameter for `path_` functions must always be a pre-open. The TL;DR; is
that usually it is, but it may not be (e.g. in our zig-cc example we can
see any directory FD, not just pre-opens).
Finally, this fixes a bug in our path resolution where we mistook paths
like "foo/foo" for "foo" because we only considered basenames instead of
the full path from the pre-open root.
This also makes pre-open directory lookup lazy because I noticed in
Trivy specifically, this is unnecessary for us to do eagerly, as they
change the FS at runtime per-call. In other words, any value from init
time is invalid later.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This avoids logging activity on stdio file descriptors, in order to help
make troubleshooting easier. Usually, there isn't an issue in these, yet
wasm panics are harder to read if there is also logging of the ..
logging.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This consolidates internal code to syscallfs, which removes the fs.FS
specific path rules, except when adapting one to syscallfs. For example,
this allows the underlying filesystem to decide if relative paths are
supported or not, as well any EINVAL related concerns.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This stubs all remaining syscalls for `GOARCH=wasm GOOS=js` to return
ENOSYS, instead of panic'ing. This allows us to see the parameters it
receives.
For example:
```
==> go.syscall/js.valueCall(fs.truncate(path=/tmp/_Go_TestTruncate135754730,length=0))
<== (err=function not implemented,ok=false)
```
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This masks interfaces returned by `fs.File` so that we don't
accidentally allow writes when opened for reading. This also adds
`syscall.NewReadFS` which can enforce read-only access in general, such
as would be ideal for tests that try to read files from the host root
filesystem (e.g. /etc/passwd).
Signed-off-by: Adrian Cole <adrian@tetrate.io>
As noted in slack, we are unlikley to long term use fs.FS internally.
This ensures we attempt to cast to syscallfs.FS for all I/O by panicing
on fs.Open.
Signed-off-by: Adrian Cole <adrian@tetrate.io>
This adds ExportedFunctionDefinitions and ExportedMemoryDefinitions to
api.Module so that those who can't access CompileModule can see them.
Fixes#839
Signed-off-by: Adrian Cole <adrian@tetrate.io>
