main.c

// Main file of the serial port project.
// NOTE: This file must not be changed.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "application_layer.h"

#define N_TRIES 3
#define TIMEOUT 4


// Arguments:
//   $1: /dev/ttySxx
//   $2: baud rate
//   $3: tx | rx
//   $4: filename
int main(int argc, char *argv[])
{
    if (argc < 5) {
        printf("Usage: %s /dev/ttySxx baudrate tx|rx filename\n", argv[0]);
        exit(1);
    }

    const char *serialPort = argv[1];
    const int baudrate = atoi(argv[2]);
    const char *role = argv[3];
    const char *filename = argv[4];

    // Validate baud rate
    switch (baudrate) {
        case 1200:
        case 1800:
        case 2400:
        case 4800:
        case 9600:
        case 19200:
        case 38400:
        case 57600:
        case 115200:
            break;
        default:
            printf("Unsupported baud rate (must be one of 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200)\n");
            exit(2);
    }

    // Validate role
    if (strcmp("tx", role) != 0 && strcmp("rx", role) != 0) {
        printf("ERROR: Role must be \"tx\" or \"rx\"\n");
        exit(3);
    }

    printf("Starting link-layer protocol application\n"
           "  - Serial port: %s\n"
           "  - Role: %s\n"
           "  - Baudrate: %d\n"
           "  - Number of tries: %d\n"
           "  - Timeout: %d\n"
           "  - Filename: %s\n",
           serialPort,
           role,
           baudrate,
           N_TRIES,
           TIMEOUT,
           filename);

    applicationLayer(serialPort, role, baudrate, N_TRIES, TIMEOUT, filename);

    return 0;
}