feat: redirection rules

This commit is contained in:
Gu://em_ 2026-01-24 15:34:10 +01:00
parent 18c1da6bdf
commit 32f56beb6b
8 changed files with 218 additions and 25 deletions

View file

@ -0,0 +1,28 @@
#include "grammar_advanced.h"
#include <stdio.h>
#include "grammar_basic.h"
struct ast *parse_redirection(struct lexer_context *ctx)
{
struct token *token = PEEK_TOKEN();
if (token->type == TOKEN_IONUMBER)
{
// TODO
POP_TOKEN();
token = PEEK_TOKEN();
}
if (token->type != TOKEN_REDIRECTION)
{
puts("Syntax error: expected a redirection token but got something "
"else");
return NULL;
}
}
struct ast *parse_prefix(struct lexer_context *ctx)
{
return parse_redirection(ctx);
}

View file

@ -1,4 +1,27 @@
#ifndef GRAMMAR_ADVANCED_H
#define GRAMMAR_ADVANCED_H
#include "grammar.h"
// === Functions
/*
* @brief parses a redirection rule
*
* @code redirection = [IONUMBER] ( '>' | '<' | '>>' | '>&' | '<&' | '>|' | '<>' ) WORD ;
*
* @first TOKEN_IONUMBER, TOKEN_REDIRECTION
*/
struct ast *parse_redirection(struct lexer_context *ctx);
/*
* @brief parses a prefix rule
*
* @code prefix = redirection ;
*
* @first first(redirection)
*/
struct ast *parse_prefix(struct lexer_context *ctx);
#endif /* ! GRAMMAR_ADVANCED_H */

View file

@ -3,9 +3,9 @@
#include <stdio.h>
#include <string.h>
#include "../lexer/lexer.h"
#include "../utils/lists/lists.h"
#include "grammar.h"
#include "grammar_advanced.h"
// === Static functions
@ -124,46 +124,86 @@ struct ast *parse_command(struct lexer_context *ctx)
struct ast *parse_simple_command(struct lexer_context *ctx)
{
struct list *command_elements = NULL;
struct token *token = PEEK_TOKEN();
// WORD
struct token *token = POP_TOKEN();
if (token->type != TOKEN_WORD)
{
puts("Expected a command but got a different token type");
return NULL;
}
char *command = strdup(token->data);
command_elements = list_append(command_elements, command);
token = PEEK_TOKEN();
// Eventual elements
while (token->type == TOKEN_WORD)
{
token = pop_token(ctx);
if (token == NULL)
// Get element
struct ast *element = parse_element(ctx);
if (element == NULL)
{
// TODO free
list_deep_destroy(command_elements);
return NULL;
}
char *word = strdup(token->data);
if (word == NULL)
// Get element type
if (ast_is_word(element))
{
// TODO free
puts("Internal error: Couldn't copy token content (is memory full "
"?)");
struct ast_word *element_word = ast_get_word(element);
command_elements =
list_append(command_elements, element_word->word);
}
else if (ast_is_redir(element))
{
// TODO
puts("NOT IMPLEMENTED");
return NULL;
}
command_elements = list_append(command_elements, word);
token = peek_token(ctx);
if (token == NULL)
else
{
// TODO free
puts("Internal error: unexpected return value from parse_element "
"in parse_simple_command");
list_deep_destroy(command_elements);
return NULL;
}
// Forward
POP_TOKEN();
token = PEEK_TOKEN();
}
// Result
struct ast *result = ast_create_command(command_elements);
if (result == NULL)
{
// TODO free
list_deep_destroy(command_elements);
return NULL;
}
return result;
}
struct ast *parse_element(struct lexer_context *ctx)
{
struct token *token = PEEK_TOKEN();
if (token->type == TOKEN_WORD)
{
// TODO
puts("NOT IMPLEMENTED");
return NULL;
}
else if (token->type == TOKEN_IONUMBER || token->type == TOKEN_REDIRECTION)
{
return parse_redirection(ctx);
}
else
{
puts("Syntax error: unexpected token at parse_element");
return NULL;
}
}
struct ast *parse_shell_command(struct lexer_context *ctx)
{
return parse_if_rule(ctx);

View file

@ -6,7 +6,8 @@
// === Functions
/* @brief: parses a list of [and_or] rules separated by semicolons and that
/*
* @brief parses a list of [and_or] rules separated by semicolons and that
* ends by a newline
*
* @code list = and_or { ';' and_or } [ ';' ] ;
@ -15,7 +16,8 @@
*/
struct ast *parse_list(struct lexer_context *ctx);
/* @brief Only parses a pipeline rule for the moment
/*
* @brief Only parses a pipeline rule for the moment
*
* @code and_or = pipeline { ( '&&' | '||' ) {'\n'} pipeline } ;
*
@ -23,7 +25,8 @@ struct ast *parse_list(struct lexer_context *ctx);
*/
struct ast *parse_and_or(struct lexer_context *ctx);
/* @brief Only parses a command rule for the moment
/*
* @brief Only parses a command rule for the moment
*
* @code pipeline = command ;
*
@ -31,7 +34,8 @@ struct ast *parse_and_or(struct lexer_context *ctx);
*/
struct ast *parse_pipeline(struct lexer_context *ctx);
/* @brief Parses a simple command rule or a shell command rule depending on
/*
* @brief Parses a simple command rule or a shell command rule depending on
* the first token.
* @note
* TOKEN_WORD => simple_command
@ -44,7 +48,8 @@ struct ast *parse_pipeline(struct lexer_context *ctx);
*/
struct ast *parse_command(struct lexer_context *ctx);
/* @brief Parses a simple list of words (command and arguments)
/*
* @brief Parses a simple list of words (command and arguments)
* ending by a separator
*
* @code simple_command = WORD { element } ;
@ -53,7 +58,19 @@ struct ast *parse_command(struct lexer_context *ctx);
*/
struct ast *parse_simple_command(struct lexer_context *ctx);
/* @brief Only parses if rules for the moment
/*
* @brief Parses an element rule
*
* @code element = WORD
* | redirection
* ;
*
* @first WORD, first(redirection)
*/
struct ast *parse_element(struct lexer_context *ctx);
/*
* @brief Only parses if rules for the moment
*
* @code shell_command = if_rule ;
*
@ -61,7 +78,8 @@ struct ast *parse_simple_command(struct lexer_context *ctx);
*/
struct ast *parse_shell_command(struct lexer_context *ctx);
/* @brief Parses a if rule (condition, then-clause, elif-clause, else-clause)
/*
* @brief Parses a if rule (condition, then-clause, elif-clause, else-clause)
*
* @code if_rule = 'if' compound_list 'then' compound_list [else_clause] 'fi' ;
*
@ -69,7 +87,8 @@ struct ast *parse_shell_command(struct lexer_context *ctx);
*/
struct ast *parse_if_rule(struct lexer_context *ctx);
/* @brief parses commands inside if/else clauses and returns the corresponding
/*
* @brief parses commands inside if/else clauses and returns the corresponding
* AST list
*
* @code compound_list = {'\n'} and_or { ( ';' | '\n' ) {'\n'} and_or } [';']
@ -79,7 +98,8 @@ struct ast *parse_if_rule(struct lexer_context *ctx);
*/
struct ast *parse_compound_list(struct lexer_context *ctx);
/* @brief
/*
* @brief
*
* @code else_clause = 'else' compound_list
* | 'elif' compound_list 'then' compound_list [else_clause]