execute_command_jobs.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   execute_command_jobs.c                             :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: jkong <jkong@student.42seoul.kr>           +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2022/06/18 16:33:05 by jkong             #+#    #+#             */
/*   Updated: 2022/06/24 20:58:50 by jkong            ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "minishell.h"
#include "safe_io.h"
#include "safe_mem.h"
#include "generic_list.h"
#include <unistd.h>
#include <sys/wait.h>

static int	_is_regular_fd(int fd)
{
	if (fd == STDIN_FILENO || fd == STDOUT_FILENO || fd == STDERR_FILENO)
		return (0);
	return (1);
}

void	do_piping(int pipe_in, int pipe_out, int pipe_next)
{
	if (pipe_in != NO_PIPE)
	{
		if (dup2(pipe_in, STDIN_FILENO) < 0)
			exit_fail("dup");
		if (_is_regular_fd(pipe_in))
			close(pipe_in);
	}
	if (pipe_out != NO_PIPE)
	{
		if (dup2(pipe_out, STDOUT_FILENO) < 0)
			exit_fail("dup");
		if (_is_regular_fd(pipe_out))
			close(pipe_out);
	}
	if (pipe_next != NO_PIPE)
		close(pipe_next);
}

pid_t	make_child(t_shell *sh)
{
	pid_t			pid;
	t_list_process	*next;

	pid = fork();
	if (pid < 0)
		exit_fail("fork");
	if (pid == 0)
	{
		list_walk((void *)sh->pid_list, free_safe);
		sh->pid_list = NULL;
		set_signal_handler(-1);
	}
	else
	{
		next = calloc_safe(1, sizeof(*next));
		next->pid = pid;
		list_append((void *)&sh->pid_list, (void *)next);
	}
	return (pid);
}

int	wait_for(t_shell *sh, pid_t pid)
{
	pid_t			got_pid;
	t_list_process	*next;
	int				status;

	status = 0;
	sh->pid_list = (void *)list_reverse((void *)sh->pid_list);
	set_signal_handler(0);
	got_pid = 0;
	while (sh->pid_list && got_pid != pid)
	{
		next = sh->pid_list->next;
		got_pid = waitpid(sh->pid_list->pid, &status, 0);
		if (got_pid < 0)
			exit_fail("waitpid");
		free(sh->pid_list);
		sh->pid_list = next;
	}
	if (pid != -1 && WIFSIGNALED(status))
		on_signal();
	set_signal_handler(1);
	return (get_exit_status(status));
}