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KernelBackend

kaish_kernel

Trait KernelBackend 

Source 
pub trait KernelBackend: Send + Sync {

Show 22 methods    // Required methods
    fn read<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
        range: Option<ReadRange>,
    ) -> Pin<Box<dyn Future<Output = Result<Vec<u8>, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn write<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
        content: &'life2 [u8],
        mode: WriteMode,
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             Self: 'async_trait;
    fn append<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
        content: &'life2 [u8],
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             Self: 'async_trait;
    fn patch<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
        ops: &'life2 [PatchOp],
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             Self: 'async_trait;
    fn list<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
    ) -> Pin<Box<dyn Future<Output = Result<Vec<DirEntry>, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn stat<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
    ) -> Pin<Box<dyn Future<Output = Result<DirEntry, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn mkdir<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn set_mtime<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
        mtime: SystemTime,
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn remove<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
        recursive: bool,
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn rename<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        from: &'life1 Path,
        to: &'life2 Path,
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             Self: 'async_trait;
    fn exists<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
    ) -> Pin<Box<dyn Future<Output = bool> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn lstat<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
    ) -> Pin<Box<dyn Future<Output = Result<DirEntry, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn read_link<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
    ) -> Pin<Box<dyn Future<Output = Result<PathBuf, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn symlink<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        target: &'life1 Path,
        link: &'life2 Path,
    ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             Self: 'async_trait;
    fn call_tool<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        name: &'life1 str,
        args: ToolArgs,
        ctx: &'life2 mut dyn ToolCtx,
    ) -> Pin<Box<dyn Future<Output = Result<ToolResult, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait,
             Self: 'async_trait;
    fn list_tools<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Result<Vec<ToolInfo>, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             Self: 'async_trait;
    fn get_tool<'life0, 'life1, 'async_trait>(
        &'life0 self,
        name: &'life1 str,
    ) -> Pin<Box<dyn Future<Output = Result<Option<ToolInfo>, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
    fn read_only(&self) -> bool;
    fn backend_type(&self) -> &str;
    fn mounts(&self) -> Vec<MountInfo>;
    fn resolve_real_path(&self, path: &Path) -> Option<PathBuf>;

    // Provided method
    fn path_access<'life0, 'life1, 'async_trait>(
        &'life0 self,
        path: &'life1 Path,
    ) -> Pin<Box<dyn Future<Output = Result<PathAccess, BackendError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait { ... }

}
Expand description

Abstract backend interface for file operations and tool dispatch.

Implementations select where a path resolves and how tools are dispatched:

  • LocalBackend — VfsRouter-backed local filesystem (the default).
  • KaijutsuBackend — CRDT-backed blocks when embedded in kaijutsu.

Required Methods§

Source

fn read<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, range: Option<ReadRange>, ) -> Pin<Box<dyn Future<Output = Result<Vec<u8>, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Read file contents, optionally with a range specification.

Source

fn write<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, path: &'life1 Path, content: &'life2 [u8], mode: WriteMode, ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, Self: 'async_trait,

Write content to a file with the specified mode.

Source

fn append<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, path: &'life1 Path, content: &'life2 [u8], ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, Self: 'async_trait,

Append content to a file.

Source

fn patch<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, path: &'life1 Path, ops: &'life2 [PatchOp], ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, Self: 'async_trait,

Apply a sequence of patch operations to a file.

Operations apply in order to one snapshot of the file, and the result is written once. If an operation fails — a CAS expected mismatch, an offset or line number past the end — the batch stops before the write and the file keeps every byte it had. A caller holding an error never has to work out how much of the batch survived.

The snapshot accumulates, so each operation sees the edits before it: offsets and line numbers are relative to the content as patched so far, not to the file as it was on entry. An insert at line 1 shifts the line numbers every later operation in the same batch uses.

The promise covers the operations, not the write that follows them. Persisting the result is write’s business, with whatever crash, concurrency, and I/O-error behavior the implementation gives it — a write that fails partway through can still leave a partial file.

Source

fn list<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, ) -> Pin<Box<dyn Future<Output = Result<Vec<DirEntry>, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

List a directory’s entries.

Source

fn stat<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, ) -> Pin<Box<dyn Future<Output = Result<DirEntry, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Stat a path (following symlinks).

Source

fn mkdir<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Create a directory.

Source

fn set_mtime<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, mtime: SystemTime, ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Set the modification time of an existing path.

Read-only or purely-virtual mounts reject rather than silently succeeding — touch on an existing file must route through here, never escape to the host via resolve_real_path.

Source

fn remove<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, recursive: bool, ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Remove a file, directory, or symlink; recursive descends into a directory. The final component is never followed: a symlink is unlinked and its target kept, and a link to a directory is not descended into.

Source

fn rename<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, from: &'life1 Path, to: &'life2 Path, ) -> Pin<Box<dyn Future<Output = Result<(), BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, Self: 'async_trait,

Rename/move a path. Neither side follows a final symlink: a symlink source moves as a link, and a symlink at the destination is replaced, never written through.

Source

fn exists<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, ) -> Pin<Box<dyn Future<Output = bool> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Whether a path exists, following symlinks: a dangling link does not exist, and an error reads as false. Use lstat to ask whether a link is present.

Source

fn lstat<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, ) -> Pin<Box<dyn Future<Output = Result<DirEntry, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Stat a path without following symlinks.

Read a symlink’s target as stored, without resolving it.

Create a symlink at link pointing to target. The target is stored verbatim; a relative target resolves from the link’s directory. An absolute target is rewritten relative to the link when both are on one mount, and refused when they are not.

Source

fn call_tool<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, name: &'life1 str, args: ToolArgs, ctx: &'life2 mut dyn ToolCtx, ) -> Pin<Box<dyn Future<Output = Result<ToolResult, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, Self: 'async_trait,

Call a tool by name with the given arguments and execution context.

For local backends, this executes the tool directly via ToolRegistry. For remote backends (e.g. kaijutsu), this may serialize the call and forward it to the parent process.

Source

fn list_tools<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<Vec<ToolInfo>, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, Self: 'async_trait,

List available external tools.

Source

fn get_tool<'life0, 'life1, 'async_trait>( &'life0 self, name: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<ToolInfo>, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Get information about a specific tool.

Source

fn read_only(&self) -> bool

Returns true if this backend is read-only.

Source

fn backend_type(&self) -> &str

Returns the backend type identifier (e.g. “local”, “kaijutsu”).

Source

fn mounts(&self) -> Vec<MountInfo>

List all mount points.

Source

fn resolve_real_path(&self, path: &Path) -> Option<PathBuf>

Resolve a VFS path to a real filesystem path.

Returns Some(path) if the VFS path maps to a real filesystem (like LocalFs), or None if the path is virtual (like MemoryFs). Tools like git that hand paths to external C libraries need the real path.

Provided Methods§

Source

fn path_access<'life0, 'life1, 'async_trait>( &'life0 self, path: &'life1 Path, ) -> Pin<Box<dyn Future<Output = Result<PathAccess, BackendError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

What the kernel can do with one path: the query behind test -r, test -w, and test -x.

Neither KernelBackend::read_only nor DirEntry.permissions answers “can this path be written” alone. A read-only wrapper over an OS-writable directory reports permissive mode bits and refuses every write; a DevFs mount reports read_only() == false (so > /dev/null works) while its /dev directory accepts nothing. PathAccess::resolve combines the two, and is the only way to build a PathAccess — a caller cannot consult one fact by accident.

The default answers from stat plus this backend’s whole-backend read_only(), which is right for a backend that is uniformly read-only or uniformly writable. A backend whose mounts differ — LocalBackend, which routes through a VfsRouter — overrides this to ask the mount that owns the path.

Errors exactly as stat does: a path that does not exist is an error, not a PathAccess of all-false.

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§