Add tagged VFS undo journal, host API, and world CLI

host/src/api/mod.rs

@@ -4,6 +4,7 @@ mod auth;
 mod pages;
 mod server;
 mod ssh;
+mod undo;
 pub use server::{Listener, Options, run_with_userland};
 
 use crate::cred::{self, Caller, Cred, entry::EntryKey, webauthn::Passkeys};
@@ -23,6 +24,7 @@ pub struct Api {
     pub passkeys: Mutex<Passkeys<rusqlite::Connection>>,
     pub entry: EntryKey,
     requests: Mutex<HashMap<u32, (Instant, u32)>>,
+    journal: Mutex<Option<Arc<sausage_vfs::journal::Journal>>>,
 }
 impl Api {
     /// Own the connection and ceremony state shared by both transports.
@@ -51,8 +53,12 @@ impl Api {
             passkeys: Mutex::new(passkeys),
             entry,
             requests: Mutex::new(HashMap::new()),
+            journal: Mutex::new(None),
         }
     }
+    pub(crate) fn attach_journal(&self, journal: Option<Arc<sausage_vfs::journal::Journal>>) {
+        *self.journal.lock().unwrap() = journal;
+    }
     fn rate_limit(&self, caller: &Caller) -> Result<()> {
         let now = Instant::now();
         let mut requests = self.requests.lock().map_err(|_| Error(500, "storage"))?;
@@ -132,6 +138,9 @@ fn request_view(request: cred::requests::Request) -> Result<Value> {
 
 /// Handle a request without a network transport. Errors contain only static error kinds.
 pub async fn handle(ctx: &Api, caller: Caller, request: Request<Bytes>) -> Response<Bytes> {
+    if request.uri().path() == "/undo" || request.uri().path().starts_with("/undo/") {
+        return undo::handle(ctx, caller, request).await;
+    }
     respond(ctx, caller, request)
 }
 fn respond(ctx: &Api, caller: Caller, request: Request<Bytes>) -> Response<Bytes> {