42_minishell/execution.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   execution.c                                        :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: cchauvet <cchauvet@student.42angoulem      +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2023/02/21 12:45:16 by cchauvet          #+#    #+#             */
/*   Updated: 2023/02/21 22:26:54 by cchauvet         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "libftx/libftx.h"
#include "minishell.h"
#include <unistd.h>

static char	*ft_get_executable_path(char *executable_name, t_list **env)
{
	char	*path;
	char	*temp;
	char	**tab;
	size_t	i;

	if (executable_name == NULL)
		return (NULL);
	path = NULL;
	if (executable_name[0] == '.' || executable_name[0] == '/')
	{
		path = ft_strdup(executable_name);
		if (path == NULL)
		{
			ft_eprintf("minishell: malloc failed\n");
			return (NULL);
		}
		if (access(path, X_OK) == 0)
		{
			ft_eprintf("minishell: %s: permission denied\n", path);
			return (NULL);
		}
	}
	else
	{
		tab = ft_split(get_value_by_key("PATH", env), ':');
		if (tab == NULL)
			return (NULL);
		i = 0;
		while (tab[i] != NULL)
		{
			temp = ft_strmerger(3, tab[i], "/", executable_name);
			if (temp == NULL)
			{
				ft_freer_tab_ultimate(1, tab);
				free(executable_name);
				ft_eprintf("minishell: malloc failed\n");
			}
			if (access(temp, X_OK) == 0)
			{
				path = temp;
				break ;
			}
			free(temp);
			i++;
		}
		if (path == NULL)
		{
			ft_eprintf("%s: command not found\n", executable_name);
		}
		ft_freer_tab_ultimate(1, tab);
	}
	return (path);
}

static int	ft_excutor(t_cmd *cmd, t_list **env)
{
	int		pid;
	int		return_value;
	char	**tab;

	if (cmd->fd_in == -1 || cmd->fd_out == -1)
		return (1);
	pid = fork();
	if (pid == -1)
		return (1);
	if (pid == 0)
	{
		tab = env_to_strs(env);
		if (tab == NULL)
			return (1);
		tab = NULL;
		dup2(cmd->fd_out, 1);
		dup2(cmd->fd_in, 0);
		execve(cmd->executable, cmd->args, tab);
	}
	else
		waitpid(pid, &return_value, 0);
	return (return_value);
}

static int	ft_own_cmd(t_list **env, t_cmd *cmd)
{
	int	return_code;

	return_code = -1;
	if (ft_strcmp(cmd->executable, "pwd") == 0)
		return_code = pwd(cmd->fd_out);
	else if (ft_strcmp(cmd->executable, "env") == 0)
		return_code = print_env(env, cmd->fd_out);
	else if (ft_strcmp(cmd->executable, "export") == 0)
		return_code = (print_export(env, cmd->fd_out));
	else if (ft_strcmp(cmd->executable, "cd") == 0)
		return_code = (move_folder(cmd->args[0], cmd->fd_out));
	/* if (ft_strcmp(cmd->executable, "unset") == 0) */
	/* 	return_code = (unset(env, cmd->args, cmd->fd_out)); */
	else if (ft_strcmp(cmd->executable, "echo") == 0)
		return_code = (echo(cmd->fd_out, cmd->args + 1));
	else if (ft_strcmp(cmd->executable, "exit") == 0)
		return_code = -2;
	if (return_code != -1)
		cmd->executable = NULL;
	return (return_code);
}

int	ft_cmds_executor(t_data *data, t_list **cmds)
{
	t_cmd	*content;
	t_list	*current;
	char	*return_value;
	int		cmd_return;
	int		fds[2];

	current = *cmds;
	while (current != NULL)
	{
		content = current->content;
		if (current->next != NULL)
		{
			if (pipe(fds) == -1)
			{
				ft_eprintf("minishell: pipe failed\n");
				return (1);
			}
			content->fd_out = fds[1];
			((t_cmd *) current->next->content)->fd_in = fds[0];
		}
		cmd_return = ft_own_cmd(data->env, content);
		if (cmd_return == -1)
		{
			content->executable = ft_get_executable_path(
					content->executable, data->env);
			if (content->executable != NULL)
				cmd_return = ft_excutor(content, data->env);
		}
		else if (cmd_return == -2)
			return (-1);
		data->exit_code = cmd_return;
		return_value = ft_itoa(cmd_return);
		if (return_value == NULL)
		{
			ft_eprintf("minishell: malloc failed\n");
			return (1);
		}
		if (content->fd_in > 2)
			close(content->fd_in);
		if (content->fd_out > 2)
			close(content->fd_out);
		set_value_by_key("?", return_value, data->env);
		current = current->next;
	}
	return (0);
}