import { MountBackend } from '@struktoai/mirage-core/types';
import type { Workspace } from '@struktoai/mirage-core/workspace/workspace/workspace';
/**
 * FSKit mounts only under /Volumes. Anywhere else the mount fails with an
 * opaque driver error, so the rule is enforced up front rather than
 * discovered at run time (github.com/strukto-ai/mirage#82).
 */
export declare const FSKIT_MOUNT_ROOT = "/Volumes";
/**
 * Coerce a user-supplied backend name into a MountBackend.
 *
 * Missing means vfs, everywhere: an absent `backend` in YAML, `undefined`
 * here, and the `MountSpecOptions` default all resolve to the same thing.
 * Callers that need a kernel mount say so explicitly rather than relying on
 * this function to reinterpret an absent value.
 */
export declare function resolveBackend(value?: string | null): MountBackend;
/** Reject a backend that registers nothing with the kernel. */
export declare function requireKernelBackend(backend: MountBackend): void;
/**
 * Reject a backend the current platform cannot serve.
 *
 * FSKit works from TypeScript: `fuse.node` links `/usr/local/lib/
 * libfuse.2.dylib` by absolute path (the `libosxfuse.2.dylib` it ships is a
 * stub with that install name), so on a machine with macFUSE 5.x the
 * `backend=fskit` option reaches the same libfuse Python uses. Verified
 * with a live mount; see examples/typescript/fuse/fskit.ts.
 */
export declare function checkPlatform(backend: MountBackend): void;
/** Reject a mountpoint the backend cannot mount on. */
export declare function checkMountpoint(backend: MountBackend, mountpoint: string): void;
/**
 * Mounts under `rootPrefix` whose files cannot be sized without reading
 * them. Mirrors Python's `Ops.unsized_mounts`.
 */
export declare function unsizedMounts(ws: Workspace, rootPrefix?: string): [string, string][];
/**
 * Warn when an fskit mount will serve size-unknown files as empty.
 *
 * FSKit drives reads from the size the filesystem reports and has no
 * `direct_io` escape hatch, so a resource that cannot size a file without
 * fetching it reports 0, the kernel issues no reads, and every such file
 * comes back empty with exit code 0 (verified on a live fskit mount: the
 * read clamp is pinned at lookup-time size and never refreshed). The mount
 * proceeds anyway: per-backend size push-down is closing this gap, so the
 * degraded mounts are named loudly here rather than refused.
 */
export declare function checkSizes(backend: MountBackend, ws: Workspace, rootPrefix?: string): void;
/**
 * Mounts that accept writes, in mount resolution order. Mirrors Python's
 * `Ops.writable_mounts`.
 */
export declare function writableMounts(ws: Workspace, rootPrefix?: string): [string, string][];
/**
 * Warn when an fskit mount accepts writes the shim may corrupt.
 *
 * Measured on live fskit mounts and pinned in `integ/fuse/truth_fskit.json`: the
 * macFUSE FSKit shim flushes pages a file did not already have (a new file,
 * an empty file, a truncate-then-write) as NUL bytes of the right length,
 * and appended regions arrive intact or zeroed depending on cache state.
 * Metadata ops (create, mkdir, rename, unlink) are reliable. The writer sees
 * no error either way, so the corruption is silent; the mount proceeds with
 * a warning naming the writable mounts.
 */
export declare function checkWrites(backend: MountBackend, ws: Workspace, rootPrefix?: string): void;
/**
 * Resolve a backend for a kernel mount and run every guard it implies.
 *
 * One entry point, so a new mount path cannot pick up fskit support while
 * silently skipping the macOS, /Volumes, or size checks.
 */
export declare function prepareBackend(value: string | undefined, ws?: Workspace, mountpoint?: string, rootPrefix?: string): MountBackend;
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