read-bytes/write-bytes go through UTF-8 (with a latin1 fallback), which mangles
arbitrary binary — gzip payloads, TLS records, any non-text body. An HTTP client
moving bytes between jolt byte-arrays and foreign socket/zlib/OpenSSL buffers
needs byte-exact transfer. read-array returns a fresh byte-array of n bytes from
foreign memory; write-array copies a byte-array's bytes into a pointer. Test
covers a round-trip preserving high bytes (200, 255).
A jolt library can now bind its own native dependencies and expose a Clojure API
over them — no jolt built-in required. This is the foundation for moving the
http-client / db / adapter functionality out of the host and into real libraries.
- jolt.ffi/foreign-fn (sugar: defcfn) is a compiler special form: a compile-time
-typed C signature lowers to a real Chez foreign-procedure (analyzer :ffi-fn ->
backend foreign-procedure), so calls are typed and marshaled, not eval'd.
- host/chez/ffi.ss provides the rest under jolt.ffi: load-library, alloc/free,
read/write/sizeof, ptr<->string, null/null?. Loaded after the loader snapshot
so a library's (require '[jolt.ffi]) still loads the macro side.
- Types: int/uint/long/ulong/int64/uint64/size_t/ssize_t/iptr/uptr/double/float/
pointer/string/void/uint8/char.
Validated end to end: a pure-Clojure file binds libc (getpid/strlen/abs) and
libsqlite3 (open/prepare/step/column/finalize over out-param pointers) and runs a
query. Gate test test/chez/ffi-binding-test.ss (make ffi); selfhost holds.