sandbox

Documentation

Overview

Package sandbox runs image decoding in an isolated subprocess.

The caller's binary must call MaybeRunWorker() at the very top of main() so the child process can identify itself and apply OS-level restrictions before doing any work:

func main() {
    termimage.MaybeRunWorker()
    // ... normal startup
}

Index

• func Decode(path string) (*image.NRGBA, error)
• func DecodeBytes(data []byte) (*image.NRGBA, error)
• func DecodeBytesContext(ctx context.Context, data []byte) (*image.NRGBA, error)
• func DecodeContext(ctx context.Context, path string) (*image.NRGBA, error)
• func IsWorker() bool
• func MaybeRunWorker()

Functions

func Decode

func Decode(path string) (*image.NRGBA, error)

Decode spawns a sandboxed worker subprocess to decode the image at path. Returns an NRGBA image whose pixels were produced inside the sandbox.

func DecodeBytes

func DecodeBytes(data []byte) (*image.NRGBA, error)

DecodeBytes spawns a sandboxed worker subprocess to decode raw image bytes piped over stdin. Used for data: URIs and remote URLs where there is no on-disk file to grant access to.

func DecodeBytesContext

func DecodeBytesContext(ctx context.Context, data []byte) (*image.NRGBA, error)

DecodeBytesContext is DecodeBytes with caller-supplied context.

func DecodeContext

func DecodeContext(ctx context.Context, path string) (*image.NRGBA, error)

DecodeContext is Decode with caller-supplied context for cancellation.

func IsWorker

func IsWorker() bool

IsWorker reports whether this process was spawned as a sandbox worker.

func MaybeRunWorker

func MaybeRunWorker()

MaybeRunWorker checks if this process is a worker. If so, it applies OS-level sandbox restrictions, decodes the image from stdin, writes the raw pixel data to stdout, and exits. Call this at the start of main().