wafer-web: add set_prompter for a JS-backed READ-PASSWORD

Browser consumers (kelvar) need a host-provided password prompt so the
master never appears on the command line. Exposes a single method:

    WaferRepl::set_prompter(js_sys::Function) -> Result<(), JsError>

Given a JS function `(prompt: string) => string`, registers it as the
Forth word `READ-PASSWORD` with stack effect

    ( prompt-addr prompt-u -- pw-addr pw-u )

The returned bytes land in WAFER's PAD region. Enforces PAD_SIZE-1 as
a hard upper bound — a silent truncation would cause a derived password
to mismatch the one used during setup, which is exactly the failure
mode we are trying to avoid.

`js_sys::Function` is !Send/!Sync but `HostFn` requires both. In a
browser WASM build there is only ever one thread, so wrap it in
`send_wrapper::SendWrapper`, which panics if accessed off-thread — an
honest guard rather than a lie.

This commit is contained in:

Oleksandr Kozachuk

2026-04-14 22:56:37 +02:00

parent 55caf38ab5

commit 9150696807

5 changed files with 169 additions and 43 deletions

									
										Cargo.toml
									
		+1
		
												View File
												
				@@ -50,3 +50,4 @@ proptest = "1"

				insta = "1"

				sha1 = "0.11"

				sha2 = "0.11"

				send_wrapper = "0.6"