Userspace/apps/system/init/init.c

#include <sys/wait.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdint.h>
#include <stdio.h>
#include "aux.h"

#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))

void test_args(int argc, char *argv[], char *envp[])
{
	printf("%p %p %p\n", (void *)(uint64_t)&argc, (void *)&argv, (void *)&envp);
	printf("I have %d arguments\n", argc);
	for (int i = 0; i < argc; i++)
		printf("argv[%d] = (%p) %s\n", i, argv[i], argv[i]);

	int envc = 0;
	while (envp[envc] != NULL)
		envc++;

	printf("I have %d environment variables\n", envc);
	for (int i = 0; i < envc; i++)
		printf("envp[%d] = (%p) %s\n", i, envp[i], envp[i]);

	Elf64_auxv_t *auxv;
	char **e = envp;

	while (*e++ != NULL)
		;

	for (auxv = (Elf64_auxv_t *)e; auxv->a_type != AT_NULL; auxv++)
		printf("auxv: %ld %#lx\n", auxv->a_type, auxv->a_un.a_val);
}

int main(int argc, char *argv[], char *envp[])
{
	freopen("/dev/tty", "w", stdout);
	freopen("/dev/tty", "w", stderr);

	test_args(argc, argv, envp);
	FILE *test = fopen("/Test.txt", "r");
	if (test == NULL)
	{
		printf("Failed to open file\n");
		return 1;
	}

	printf("Test.txt contents: ");
	char ch;
	do
	{
		ch = fgetc(test);
		putchar(ch);
	} while (ch != EOF);

	fclose(test);

	pid_t pid;
	int status;

	pid = fork();

	if (pid == 0) // Child process
	{
		printf("Creating shell process\n");
		char *args[] = {"/bin/sh", NULL};
		execv(args[0], args);
		exit(EXIT_FAILURE);
	}
	else if (pid > 0)
	{
		wait(&status);
		if (WIFEXITED(status))
		{
			printf("Child process exited with code: %d\n", WEXITSTATUS(status));
			return WEXITSTATUS(status);
		}
		else
		{
			printf("Execution failed.\n");
			exit(EXIT_FAILURE);
		}
	}
	else
	{
		printf("\eFF0000Failed to create the process.\n");
		exit(EXIT_FAILURE);
	}

	return 0;
}