gotosocial/vendor/github.com/tetratelabs/wazero/experimental/checkpoint.go
kim 1e7b32490d
[experiment] add alternative wasm sqlite3 implementation available via build-tag (#2863)
This allows for building GoToSocial with [SQLite transpiled to WASM](https://github.com/ncruces/go-sqlite3) and accessed through [Wazero](https://wazero.io/).
2024-05-27 17:46:15 +02:00

49 lines
2 KiB
Go

package experimental
import (
"context"
"github.com/tetratelabs/wazero/internal/expctxkeys"
)
// Snapshot holds the execution state at the time of a Snapshotter.Snapshot call.
type Snapshot interface {
// Restore sets the Wasm execution state to the capture. Because a host function
// calling this is resetting the pointer to the executation stack, the host function
// will not be able to return values in the normal way. ret is a slice of values the
// host function intends to return from the restored function.
Restore(ret []uint64)
}
// Snapshotter allows host functions to snapshot the WebAssembly execution environment.
type Snapshotter interface {
// Snapshot captures the current execution state.
Snapshot() Snapshot
}
// EnableSnapshotterKey is a context key to indicate that snapshotting should be enabled.
// The context.Context passed to a exported function invocation should have this key set
// to a non-nil value, and host functions will be able to retrieve it using SnapshotterKey.
//
// Deprecated: use WithSnapshotter to enable snapshots.
type EnableSnapshotterKey = expctxkeys.EnableSnapshotterKey
// WithSnapshotter enables snapshots.
// Passing the returned context to a exported function invocation enables snapshots,
// and allows host functions to retrieve the Snapshotter using GetSnapshotter.
func WithSnapshotter(ctx context.Context) context.Context {
return context.WithValue(ctx, expctxkeys.EnableSnapshotterKey{}, struct{}{})
}
// SnapshotterKey is a context key to access a Snapshotter from a host function.
// It is only present if EnableSnapshotter was set in the function invocation context.
//
// Deprecated: use GetSnapshotter to get the snapshotter.
type SnapshotterKey = expctxkeys.SnapshotterKey
// GetSnapshotter gets the Snapshotter from a host function.
// It is only present if WithSnapshotter was called with the function invocation context.
func GetSnapshotter(ctx context.Context) Snapshotter {
return ctx.Value(expctxkeys.SnapshotterKey{}).(Snapshotter)
}