42_minishell/execution.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   execution.c                                        :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: cchauvet <cchauvet@student.42angoulem      +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2023/02/21 12:45:16 by cchauvet          #+#    #+#             */
/*   Updated: 2023/02/28 14:56:05 by erey-bet         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

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

static char	*ft_get_executable_path(t_data *data, char *executable_name)
{
	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", data->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);
			data->exit_code = 127;
		}
		ft_freer_tab_ultimate(1, tab);
	}
	return (path);
}

static int	ft_executor(t_data *data, t_cmd *cmd)
{
	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(data->env);
		if (tab == NULL)
			return (1);
		dup2(cmd->fd_out, 1);
		dup2(cmd->fd_in, 0);
		execve(cmd->executable, cmd->args, tab);
	}
	else
		waitpid(pid, &return_value, 0);
	data->exit_code = return_value;
	return (return_value);
}

static int	ft_own_cmd(t_data *data, t_cmd *cmd)
{
	int	return_code;
	int	exit_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(data->env, cmd->fd_out);
	else if (ft_strcmp(cmd->executable, "export") == 0)
		return_code = (export(data->env,cmd->args + 1, cmd->fd_out));
	else if (ft_strcmp(cmd->executable, "cd") == 0)
		return_code = (move_folder(cmd->args + 1, cmd->fd_out));
	if (ft_strcmp(cmd->executable, "unset") == 0)
		return_code = (unset(data->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)
	{
		exit_code = ft_exit(cmd->args + 1);
		if (exit_code != -1)
		{
			data->exit_code = exit_code;
			return_code = -2;
		}
	}
	if (return_code != -1)
	{
		cmd->executable = NULL;
		data->exit_code = return_code;
	}
	return (return_code);
}

int	ft_cmds_executor(t_data *data, t_list **cmds)
{
	t_cmd	*content;
	t_list	*current;
	int		exit_code;
	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];
		}
		exit_code = ft_own_cmd(data, content);
		if (exit_code == -1)
		{
			content->executable = ft_get_executable_path(data,
				content->executable);
			if (content->executable != NULL)
				exit_code = ft_executor(data, content);
		}
		else if (exit_code == -2)
			return (1);
		if (ft_gen_exit_code_var(data))
			return (1);
		if (content->fd_in > 2)
			close(content->fd_in);
		if (content->fd_out > 2)
			close(content->fd_out);
		current = current->next;
	}
	return (0);
}