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shell.c
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shell.c
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#include "shell.h"
/**
* get_func - returns functions for builtin commands
* @arr: the line splitted into command and args
*
* Return: the function that prints the builtin command
*/
int (*get_func(char **arr))(sh_data *)
{
built_in sh[] = {
{"exit", my_exit},
{"env", my_env},
{"setenv", my_set},
{"unsetenv", my_unset},
{"cd", my_cd},
{"alias", my_alias},
{NULL, NULL}
};
int i = 0;
if (arr != NULL)
{
while (sh[i].func != NULL)
{
if (my_strcmp(sh[i].str, arr[0]) == 0)
{
return (sh[i].func);
}
else
i++;
}
}
return (NULL);
}
/**
* non_interact - runs the shell in non interactive mode
* @shell: the shell data struct
*
* Return: non, uses exit with a status
*/
void non_interact(sh_data *shell)
{
char *path;
shell->interact = 0;
for (; ;)
{
path = check_shell(shell);
if (!path && shell->builtin == 0)
my_exit(shell);
else if (!path && shell->builtin == 1)
continue;
shell->builtin = 0;
shell->pid = fork();
if (shell->pid == 0)
{
shell->status = execve(path, shell->arr, shell->_environ);
if (shell->status == -1)
{
write(STDERR_FILENO, shell->av[0], my_strlen(shell->av[0]));
write(STDERR_FILENO, ": ", 2);
write(STDERR_FILENO, shell->arr[0], my_strlen(shell->arr[0]));
write(STDERR_FILENO, ": Permission denied\n", 20);
free(path);
shell->status = 13;
my_exit(shell);
}
}
else
{
wait(&shell->status);
shell->status = WEXITSTATUS(shell->status);
}
free_arr2(shell->arr);
free(path);
}
}
/**
* loop_shell - runs the shell continously
* @shell: the shell data
*
* Return: void
*/
void loop_shell(sh_data *shell)
{
char *path;
if (shell->av[1])
exit (98);
else if (!isatty(STDIN_FILENO))
non_interact(shell);
else
{
for (; ;)
{
write(STDOUT_FILENO, "($) ", 4);
fflush(stdout);
path = check_shell(shell);
if (!path)
continue;
shell->pid = fork();
if (shell->pid == 0)
{
shell->status = execve(path, shell->arr, shell->_environ);
if (shell->status == -1)
{
write(STDERR_FILENO, shell->av[0], my_strlen(shell->av[0]));
write(STDERR_FILENO, ": ", 2);
write(STDERR_FILENO, shell->arr[0], my_strlen(shell->arr[0]));
write(STDERR_FILENO, ": Permission denied\n", 20);
free(path);
shell->status = 13;
my_exit(shell);
}
}
else
{
wait(&shell->status);
shell->status = WEXITSTATUS(shell->status);
}
free_arr2(shell->arr);
free(path);
}
}
}
/**
* check_shell - checks the shell commands, paths and builtins
* @shell: pointer to shell data structure
*
* Return: path or NULL
*/
char *check_shell(sh_data *shell)
{
int (*built_in_func)(sh_data *sh);
char *path;
shell->arr = get_commands(shell, shell->line, shell->length);
if (!shell->arr)
{
free(shell->line);
return (NULL);
}
check_alias(shell);
expand_var(shell);
built_in_func = get_func(shell->arr);
if (built_in_func != NULL)
{
shell->status = built_in_func(shell);
if (shell->arr != NULL)
free_arr2(shell->arr);
shell->builtin = 1;
return (NULL);
}
path = search_path(shell->path, shell->arr[0]);
if (!path)
{
write(STDERR_FILENO, shell->av[0], my_strlen(shell->av[0]));
write(STDERR_FILENO, ": ", 2);
write(STDERR_FILENO, shell->arr[0], my_strlen(shell->arr[0]));
write(STDERR_FILENO, ": No such file or directory\n", 28);
shell->status = 2;
free_arr2(shell->arr);
free(path);
return (NULL);
}
return (path);
}
/**
* main - main body of the shell
* @ac: command line argument count
* @av: pointer to strings of command line arguments
* @env: environment variables
*
* Return: 0 at successful exit
*/
int main(int ac, char *av[], char *env[])
{
sh_data shell;
int i;
shell.line = NULL;
shell.length = 0;
shell.interact = 1;
shell.pid = getpid();
shell.status = 0;
shell.builtin = 0;
shell.arr = NULL;
shell.alias = NULL;
(void) env;
shell.av = malloc(sizeof(char *) * (ac + 1));
for (i = 0; av[i]; i++)
shell.av[i] = my_strdup(av[0]);
shell.av[i] = NULL;
/* count th enumber of env strings to malloc a copy */
for (i = 0; environ[i]; i++)
;
shell._environ = malloc(sizeof(char *) * (i + 1));
for (i = 0; environ[i]; i++)
shell._environ[i] = my_strdup(environ[i]);
shell._environ[i] = NULL;
shell.path = path_to_list(&shell);
loop_shell(&shell);
return (0);
}