Files
minishell/src/parser/parser.c

491 lines
11 KiB
C

/* ************************************************************************** */
/* */
/* ::: :::::::: */
/* parser.c :+: :+: :+: */
/* +:+ +:+ +:+ */
/* By: sede-san <sede-san@student.42madrid.com +#+ +:+ +#+ */
/* +#+#+#+#+#+ +#+ */
/* Created: 2025/10/22 18:37:38 by sede-san #+# #+# */
/* Updated: 2026/02/13 08:17:43 by sede-san ### ########.fr */
/* */
/* ************************************************************************** */
#include "parser.h"
#include "errors.h"
static t_list *parse_tokens(
t_list *tokens
);
static t_list *ft_lstfind(
t_list *lst,
bool (*pre)(void *)
);
static void expand_variable(
char **argument,
int *i,
t_minishell *minishell
);
static void expand(
t_list **commands,
t_minishell *minishell
);
/**
* @brief Converts a command line string into a list of commands.
*
* @param line The command line string to parse.
* @param minishell The minishell instance.
*
* @return A list of commands or `NULL` on error.
*/
t_list *parse(
char *line,
t_minishell *minishell
)
{
t_list *commands;
t_list *tokens;
if (line == NULL)
return (NULL);
tokens = lex(line);
commands = parse_tokens(tokens);
ft_lstclear(&tokens, (void (*)(void *))token_clear);
expand(&commands, minishell);
return (commands);
}
/**
* @brief Converts a list of tokens into a list of commands.
*
* @param tokens The list of tokens to parse.
* @param minishell The minishell instance.
*
* @return A list of commands or `NULL` on error.
*/
static t_list *parse_tokens(
t_list *tokens
)
{
t_list *commands;
t_command *command;
t_list *current_token;
t_list *new_command;
if (tokens == NULL)
return (NULL);
commands = NULL;
current_token = tokens;
while (current_token != NULL)
{
command = command_new(&current_token);
if (command == NULL)
{
ft_lstclear(&commands, (void (*)(void *))command_clear);
return (NULL);
}
new_command = ft_lstnew(command);
if (new_command == NULL)
{
command_clear(command);
ft_lstclear(&commands, (void (*)(void *))command_clear);
return (malloc_error(), NULL);
}
ft_lstadd_back(&commands, new_command);
if (current_token != NULL)
{
if (current_token->next == NULL)
syntax_error_unexpected_token((t_token *)current_token->content);
current_token = current_token->next;
}
}
return (commands);
}
static void expand_variable(
char **argument,
int *i,
t_minishell *minishell
)
{
char *expanded;
char *variable;
char *variable_name;
const int start = *i + 1;
int end;
end = start;
while (ft_isalnum((*argument)[end]) || (*argument)[end] == '_')
end++;
variable_name = ft_substr(*argument, start, end - start);
if (variable_name == NULL)
return (minishell->exit = true, malloc_error());
variable = get_env(variable_name, minishell);
free(variable_name);
if (variable == NULL)
variable = "";
expanded = ft_strnjoin(3,
ft_substr(*argument, 0, *i),
variable,
ft_substr(*argument,end, ft_strlen(*argument) - end));
if (expanded == NULL)
return (minishell->exit = true, malloc_error());
*i += ft_strlen(variable) - 1;
free(*argument);
*argument = expanded;
}
static void expand_argument(
char **argument,
t_minishell *minishell
)
{
bool in_single_quote;
bool in_double_quote;
int i;
in_single_quote = false;
in_double_quote = false;
i = 0;
while ((*argument)[i] != '\0')
{
if ((*argument)[i] == '$' && !in_single_quote)
{
expand_variable(argument, &i, minishell);
if (*argument == NULL)
return (minishell->exit = true, malloc_error());
}
else
{
if ((*argument)[i] == '\'' && !in_double_quote)
in_single_quote = !in_single_quote;
else if ((*argument)[i] == '"' && !in_single_quote)
in_double_quote = !in_double_quote;
i++;
}
}
}
static void expand(
t_list **commands,
t_minishell *minishell
)
{
t_list *current_command;
t_command *command;
int i;
current_command = *commands;
while (current_command != NULL)
{
command = (t_command *)current_command->content;
i = 0;
while (i < command->argc)
{
expand_argument(&command->argv[i], minishell);
if (command->argv[i] == NULL)
ft_lstclear(commands, (void (*)(void *))command_clear);
i++;
}
if (command == NULL)
return (ft_lstclear(commands, (void (*)(void *))command_clear));
current_command = current_command->next;
}
}
/**
* @brief Creates a new command from a list of tokens.
*
* @param tokens The list of tokens to create the command from.
*
* @return A new command or NULL on error.
*
* @note The `tokens` pointer is moved to the next command's tokens.
*/
t_command *command_new(
t_list **tokens
)
{
t_command *command;
t_list *current_token;
t_list *delimiter_token;
command = (t_command *)ft_calloc(1, sizeof(t_command));
if (command == NULL)
return (NULL);
current_token = *tokens;
delimiter_token = ft_lstfind(current_token, (bool (*)(void *))is_pipe);
while (command != NULL && current_token != delimiter_token)
{
command_add_tokens(&command, &current_token);
}
*tokens = current_token;
return (command);
}
/**
* @brief Creates a new redirection from a list of tokens.
*
* @param tokens The list of tokens to create the redirection from.
*
* @return A new redirection or `NULL` on error.
*/
t_redirection *redirection_new(
t_list **tokens
)
{
t_redirection *redirection;
t_token *token;
redirection = (t_redirection *)malloc(sizeof(t_redirection));
if (redirection == NULL)
return (malloc_error(), NULL);
token = (t_token *)(*tokens)->content;
redirection->type = token->type;
*tokens = (*tokens)->next;
if (*tokens == NULL)
{
free(redirection);
return (syntax_error_unexpected_token(NULL), NULL);
}
token = (t_token *)(*tokens)->content;
if (token->type != TOKEN_WORD)
{
free(redirection);
while (*tokens != NULL)
*tokens = (*tokens)->next;
return (syntax_error_unexpected_token(token), NULL);
}
redirection->target = ft_strdup(token->value);
if (redirection->target == NULL)
{
free(redirection);
return (malloc_error(), NULL);
}
*tokens = (*tokens)->next;
return (redirection);
}
void redirection_clear(
t_redirection *redirection
)
{
if (redirection != NULL)
{
free(redirection->target);
free(redirection);
}
}
/**
* @brief Adds a token to a command, updating the command's arguments and
* redirections as necessary.
*
* @param command The command to add the token to.
* @param tokens The list of tokens to add to the command.
*
* @note The `command` pointer can be free'd if there is an error while adding
* the token.
*/
void command_add_tokens(
t_command **command,
t_list **tokens
)
{
t_token *token;
token = (t_token *)(*tokens)->content;
if (is_redirection(token))
redirection_add(tokens, token, command);
else
words_add(tokens, command);
}
/**
* @brief Converts a list of arguments into an array.
*
* @param args The list of arguments to convert.
* @param argc The number of arguments in the list.
*
* @return An array of arguments or `NULL` on error.
*
* @note The `args` list is cleared after the conversion and set to NULL.
*/
char **args_to_array(
t_list **args,
size_t argc
)
{
char **argv;
t_list *arg;
size_t i;
argv = (char **)malloc(sizeof(char *) * (argc + 1));
if (argv == NULL)
return (NULL);
i = 0;
arg = *args;
while (arg != NULL)
{
argv[i] = (char *)arg->content;
arg = arg->next;
i++;
}
argv[i] = NULL;
ft_lstclear_nodes(args);
return (argv);
}
/**
* @brief Adds all consecutive word tokens to a command's argv and updates its
* argc accordingly.
*
* @param command The command to add the word tokens to.
* @param tokens The list of tokens to add to the command.
*/
void words_add(
t_list **tokens,
t_command **command
)
{
t_list *args;
t_list *arg;
t_token *token;
args = NULL;
arg = *tokens;
token = (t_token *)arg->content;
while (arg != NULL && token->type == TOKEN_WORD)
{
ft_lstadd_back(&args, ft_lstnew(ft_strdup(token->value)));
(*command)->argc++;
arg = arg->next;
if (arg != NULL)
token = (t_token *)arg->content;
}
*tokens = arg;
(*command)->argv = args_to_array(&args, (*command)->argc);
ft_lstclear_nodes(&args);
}
void redirection_add(
t_list **tokens,
t_token *token,
t_command **command
)
{
t_redirection *redirection;
t_list *redirection_tokens;
redirection = redirection_new(tokens);
if (redirection == NULL)
{
command_clear(*command);
*command = NULL;
return ;
}
redirection_tokens = ft_lstnew(redirection);
if (redirection_tokens == NULL)
{
free(redirection);
return (malloc_error());
}
if (token->type == TOKEN_HEREDOC)
ft_lstadd_back(&(*command)->heredocs, redirection_tokens);
else
ft_lstadd_back(&(*command)->redirections, redirection_tokens);
}
/**
* @brief Checks if a token is a redirection token.
*
* @param token The token to check.
*
* @return `true` if the token is a redirection token, `false` otherwise.
*/
bool is_redirection(
t_token *token
)
{
return (token->type == TOKEN_REDIRECT_IN
|| token->type == TOKEN_REDIRECT_OUT
|| token->type == TOKEN_APPEND
|| token->type == TOKEN_HEREDOC);
}
void command_clear_argv(
t_command *command
)
{
int i;
if (command->argv != NULL)
{
i = 0;
while (i < command->argc)
{
free(command->argv[i]);
i++;
}
free(command->argv);
command->argv = NULL;
}
}
/**
* @brief Clears a command, freeing all associated memory.
*
* @param command The command to clear.
*/
void command_clear(
t_command *command
)
{
if (command != NULL)
{
command_clear_argv(command);
ft_lstclear(&command->redirections, (void (*)(void *))redirection_clear);
ft_lstclear(&command->heredocs, (void (*)(void *))redirection_clear);
free(command);
}
}
/**
* @brief Checks if a token is a pipe token.
*
* @param token The token to check.
*
* @return `true` if the token is a pipe token, `false` otherwise.
*/
bool is_pipe(
t_token *token)
{
return (token->type == TOKEN_PIPE);
}
/**
* @brief Finds a node in a linked list that satisfies a given predicate.
*
* @param lst The linked list to search through.
* @param pre The predicate function to apply to each node's content.
*
* @returns The first node that satisfies the predicate or `NULL` if no such
* node exists or if the list is `NULL`.
*/
t_list *ft_lstfind(
t_list *lst,
bool (*pre)(void *))
{
while (lst != NULL)
{
if (pre(lst->content))
return (lst);
lst = lst->next;
}
return (NULL);
}