Files
42_INT_07_minishell/srcs/parsing/expansions/expand_token.c
2021-12-16 03:12:32 +01:00

136 lines
3.4 KiB
C

/* ************************************************************************** */
/* */
/* ::: :::::::: */
/* expand_token.c :+: :+: :+: */
/* +:+ +:+ +:+ */
/* By: lperrey <lperrey@student.42.fr> +#+ +:+ +#+ */
/* +#+#+#+#+#+ +#+ */
/* Created: 2021/11/07 02:01:33 by lperrey #+# #+# */
/* Updated: 2021/12/16 03:03:27 by lperrey ### ########.fr */
/* */
/* ************************************************************************** */
#include "minishell.h"
static t_list *content_copy(char *content, int *i, int *quotes_state);
static t_list *content_expand(char *content, int *i);
static char *env_var_expansion(char *content, int *i);
t_list *expand_token(char *content)
{
int quotes_state;
int i;
t_list head;
t_list *expand;
head.next = NULL;
expand = &head;
quotes_state = 0;
i = 0;
while (content[i])
{
if (content[i] == '$')
expand->next = content_expand(content, &i);
else
expand->next = content_copy(content, &i, &quotes_state);
expand = expand->next;
if (!expand)
{//todo wrap
perror("expand_token() error");
return (ft_lstclear(&head.next, free));
}
}
return (head.next);
}
static t_list *content_copy(char *content, int *i, int *quotes_state)
{
int i_exp;
t_list *expand;
expand = ft_lstnew_generic(sizeof(t_list), ft_strlen(&content[*i]) + 1);
if (!expand)
return (NULL);
i_exp = 0;
while (content[*i] && (content[*i] != '$' || *quotes_state == IN_QUOTES))
{
if (content[*i] == '\'' && *quotes_state != IN_DQUOTES)
{
if (*quotes_state == IN_QUOTES)
*quotes_state = 0;
else
*quotes_state = IN_QUOTES;
}
((char *)expand->content)[i_exp++] = content[(*i)++];
}
return (expand);
}
static t_list *content_expand(char *content, int *i)
{
t_list *expand;
expand = ft_lstnew(NULL);
if (!expand)
return (NULL);
expand->content = env_var_expansion(content, i);
if (!expand->content)
{
free(expand);
return (NULL);
}
return (expand);
}
static char *retrieve_var(char *content, int *i);
static char *env_var_expansion(char *content, int *i)
{
char *expansion;
(*i)++; // skip '$'
if (content[*i] == '?')
{
(*i)++;
expansion = ft_itoa(get_last_exit_status());
}
else if (content[*i] == '_' || ft_isalpha(content[*i]))
expansion = retrieve_var(content, i);
else
{
expansion = ft_calloc(1 + 1, 1);
if (!expansion)
return (NULL);
expansion[0] = '$';
}
return (expansion);
}
static char *retrieve_var(char *content, int *i)
{
char *expansion;
char *tmp;
int i_exp;
expansion = ft_calloc(ft_strlen(&content[*i - 1]) + 1, 1); // *i - 1 for '$' skip
if (!expansion)
return (NULL);
i_exp = 0;
while (content[*i] == '_' || ft_isalnum(content[*i]))
expansion[i_exp++] = content[(*i)++];
tmp = getenv(expansion);
ft_free_null(&expansion);
if (tmp)
expansion = ft_strdup(tmp);
else
expansion = ft_calloc(1, 1);
return (expansion);
}
/*
environment variables must be POSIX NAME :
3.235 Name
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html
#tag_03_235
*/