serial_config.c

Go to the documentation of this file.

/*
 * This file is part of the Fun programming language.
 * https://fun-lang.xyz/
 *
 * Copyright 2025 Johannes Findeisen <you@hanez.org>
 * Licensed under the terms of the Apache-2.0 license.
 * https://opensource.org/license/apache-2-0
 */


#ifdef __unix__
#include <termios.h>
#endif

case OP_SERIAL_CONFIG: {
 /* Pops flow_control (int), stop_bits (int), parity (int), data_bits (int), fd (int); returns 1/0 */
 Value flowv = pop_value(vm);
 Value stopv = pop_value(vm);
 Value parityv = pop_value(vm);
 Value datav = pop_value(vm);
 Value fdv = pop_value(vm);
 int ok = 0;
#ifdef __unix__
 if (flowv.type != VAL_INT || stopv.type != VAL_INT || parityv.type != VAL_INT ||
 datav.type != VAL_INT || fdv.type != VAL_INT) {
 fprintf(stderr, "Runtime type error: serial_config expects (int fd, int data_bits, int parity, int stop_bits, int flow_control)\n");
 } else {
 int fd = (int)fdv.i;
 int data_bits = (int)datav.i;
 int parity = (int)parityv.i;
 int stop_bits = (int)stopv.i;
 int flow = (int)flowv.i;

 struct termios options;
 if (tcgetattr(fd, &options) == 0) {
 // Data bits
 options.c_cflag &= ~CSIZE;
 switch (data_bits) {
 case 5:
 options.c_cflag |= CS5;
 break;
 case 6:
 options.c_cflag |= CS6;
 break;
 case 7:
 options.c_cflag |= CS7;
 break;
 case 8:
 default:
 options.c_cflag |= CS8;
 break;
 }

 // Parity
 switch (parity) {
 case 0: // None
 options.c_cflag &= ~PARENB;
 break;
 case 1: // Odd
 options.c_cflag |= PARENB;
 options.c_cflag |= PARODD;
 break;
 case 2: // Even
 options.c_cflag |= PARENB;
 options.c_cflag &= ~PARODD;
 break;
 }

 // Stop bits
 if (stop_bits == 2) {
 options.c_cflag |= CSTOPB;
 } else {
 options.c_cflag &= ~CSTOPB;
 }

 // Flow control
#ifdef CRTSCTS
 if (flow == 1) { // Hardware (RTS/CTS)
 options.c_cflag |= CRTSCTS;
 } else {
 options.c_cflag &= ~CRTSCTS;
 }
#endif

 if (tcsetattr(fd, TCSANOW, &options) == 0) {
 ok = 1;
 }
 }
 }
#endif
 free_value(flowv);
 free_value(stopv);
 free_value(parityv);
 free_value(datav);
 free_value(fdv);
 push_value(vm, make_int(ok));
 break;
}