main.cpp

//-----------------------------------------------------------------------------
// C++ implementation of a Forth interpreter
// Copyright (c) Paulo Custodio, 2020-2026
// License: GPL3 https://www.gnu.org/licenses/gpl-3.0.html
//-----------------------------------------------------------------------------

#include "environment.h"
#include "forth.h"
#include "vm.h"
#include <iostream>
#include <cstring>

const char* FORTH_ENV = "FORTH";

static void die_usage() {
    std::cerr << "Usage: forth [-e forth] [-t] [source [args...]]" << std::endl;
    exit(EXIT_FAILURE);
}

int main(int argc, char* argv[]) {
    // parse env variable
    const char* envp = getenv(FORTH_ENV);
    if (envp != nullptr) {
        vm.input.set_text(envp, static_cast<uint>(strlen(envp)));
        f_execute(xtINTERPRET);
    }

    // parse command line
    g_argc = argc;
    g_argv = argv;
    g_interactive = false;
    bool did_forth = false;
    g_argc--;
    g_argv++;
    while (g_argc > 0 && g_argv[0][0] == '-') {
        switch (g_argv[0][1]) {
        case 'e':
            if (g_argc == 1) {
                die_usage();
            }
            else {
                g_argc--;
                g_argv++;
                vm.input.set_text(g_argv[0], static_cast<uint>(strlen(g_argv[0])));
                f_execute(xtINTERPRET);
                did_forth = true;
            }
            break;
        case 't':
            vm.user->TRACE = F_TRUE;
            break;
        default:
            die_usage();
        }
        g_argc--;
        g_argv++;
    }

    // get script, if any
    if (g_argc == 0) {
        if (!did_forth) {
            vm.input.open_terminal();
            g_interactive = true;
            f_execute(xtQUIT);
        }
    }
    else {
        const char* source = g_argv[0];
        g_argc--;
        g_argv++;

        vm.input.open_file(source);
        f_execute(xtQUIT);
    }

    return EXIT_SUCCESS;
}