diff options
Diffstat (limited to 'vendor/github.com/tetratelabs/wazero/experimental/checkpoint.go')
-rw-r--r-- | vendor/github.com/tetratelabs/wazero/experimental/checkpoint.go | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/vendor/github.com/tetratelabs/wazero/experimental/checkpoint.go b/vendor/github.com/tetratelabs/wazero/experimental/checkpoint.go new file mode 100644 index 000000000..443c5a294 --- /dev/null +++ b/vendor/github.com/tetratelabs/wazero/experimental/checkpoint.go @@ -0,0 +1,48 @@ +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) +} |