kaappi-net

Shared TCP/TLS networking library for Kaappi Scheme.

Provides TCP client, TCP server, and TLS client operations. Used by kaappi-redis, kaappi-http, and any other library that needs network I/O.

Build

Requires OpenSSL (for TLS support).

make                    # builds libkaappi_net.dylib (macOS) or .so (Linux)

Usage

export DYLD_LIBRARY_PATH=/path/to/kaappi-net
kaappi --lib-path /path/to/kaappi-net/lib your-script.scm

(import (kaappi net))

;; TCP client
(let ((fd (tcp-connect "example.com" 80)))
  (tcp-send fd (string->utf8 "GET / HTTP/1.0\r\n\r\n") 18)
  (let ((buf (make-bytevector 4096 0)))
    (tcp-recv fd buf 4096))
  (tcp-close fd))

;; TCP server
(let ((listen-fd (tcp-listen "0.0.0.0" 8080)))
  (let loop ()
    (let ((client-fd (tcp-accept listen-fd)))
      ;; handle client...
      (tcp-close client-fd)
      (loop))))

;; TLS client
(let ((ssl (tls-connect "api.github.com" 443)))
  (tls-send ssl request-bytes len)
  (tls-recv ssl buf len)
  (tls-close ssl))

API

TCP Client

Procedure	Description
(tcp-connect host port [timeout])	Connect, returns fd
(tcp-send fd buf len)	Send bytes
(tcp-recv fd buf len)	Receive bytes
(tcp-close fd)	Close socket

TCP Server

Procedure	Description
(tcp-listen host port [backlog])	Bind + listen, returns fd
(tcp-accept listen-fd)	Accept connection, returns client fd

TLS Client

Procedure	Description
(tls-connect host port [timeout])	TLS handshake with SNI + cert verify
(tls-send ssl buf len)	Send over TLS
(tls-recv ssl buf len)	Receive over TLS
(tls-close ssl)	Shutdown TLS + close socket

tls-connect/tls-send/tls-recv run the underlying socket non-blocking and retry internally on SSL_ERROR_WANT_READ/WANT_WRITE, parking on thread-sleep! between attempts. In a program that uses (kaappi fibers) this yields to the fiber scheduler, so a slow TLS handshake or response doesn't block sibling fibers; sequential programs see identical behavior to a plain blocking call.

Error

Procedure	Description
(tcp-last-error)	Last errno value

Requirements

• Kaappi with (kaappi ffi) support
• OpenSSL 3.x (brew install openssl or apt install libssl-dev)

License

MIT