crt0.c

/*
    This file is part of duckOS.
    
    duckOS is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.
    
    duckOS is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
    
    You should have received a copy of the GNU General Public License
    along with duckOS.  If not, see <https://www.gnu.org/licenses/>.
    
    Copyright (c) Byteduck 2016-2020. All rights reserved.
*/

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

extern void _init();

int main(int, char**, char**);
extern void (*__init_array_start[])(int, char**, char**);
extern void (*__init_array_end[])(int, char**, char**);
extern char** __original_environ;

int __duckos_did_init = 0;
__attribute__((constructor)) void __on_init() {
    __duckos_did_init = 1;
}

int _start(int argc, char* argv[], char* env[]) {
	environ = env;
	__original_environ = env;

    //We don't want to call the init array twice; the dynamic loader does this
    if(!__duckos_did_init) {
        __init_stdio();
        size_t ninit = __init_array_end - __init_array_start;
        for (size_t i = 0; i < ninit; i++) {
            (*__init_array_start[i])(argc, argv, env);
        }
    }

	int ret = main(argc, argv, env);
	exit(ret);
	return -1;
}