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feat: suport for the new lexer and if/else structures

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Guillem George 2026-01-14 20:53:47 +01:00
parent e9d702efb4
commit 80e4b6c2fd
3 changed files with 194 additions and 46 deletions
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46
src/parser/parser.c
View file

@ -10,25 +10,7 @@
#include "utils/lists/lists.h"
// === Static functions
/* Returns true if c is a command terminator, false otherwise
*/
static bool isterminator(char c)
{
switch (c)
{
case '\n':
case ';':
case EOF:
return true;
default:
return false;
}
}
/* Parses a simple list of words (command and arguments)
* and returns the resulting ast
*/
// ...
// === Functions
@ -37,19 +19,29 @@ struct ast *get_ast()
struct list *result_list = NULL;
struct ast *current_node = NULL;
char *token = peek_token();
if (token != NULL)
struct token *token = peek_token();
while (token != NULL && token->type != TOKEN_EOF)
{
switch (token->type)
{
case TOKEN_WORD:
struct ast *cmd = parse_simple_command();
result_list = list_append(result_list, cmd);
break;
default:
// Forward
token = pop_token();
break;
}
}
if (token == NULL)
{
puts("Internal error: cannot get the following token");
return NULL;
}
while (token[0] != EOF)
{
struct ast *cmd = parse_simple_command();
result_list = list_append(result_list, cmd);
}
struct ast *result = ast_create_list(result_list);
return result;
}

189
src/parser/parsing_utils.c
View file

@ -1,23 +1,65 @@
// === Includes
#include "parsing_utils.h"
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include "lexer/lexer.h"
#include "utils/ast/ast.h"
// === Macros
#define PEEK_TOKEN() \
peek_token(); \
if (token == NULL) \
{ \
puts("Internal error: cannot get the following token"); \
return NULL; \
}
#define POP_TOKEN() \
pop_token(); \
if (token == NULL) \
{ \
puts("Internal error: cannot get the following token"); \
return NULL; \
}
// === Static functions
/* Returns true if c is a command terminator, false otherwise
*/
static bool isterminator(struct token *token)
{
if (token == NULL)
return false;
switch (token->type)
{
case TOKEN_NEWLINE:
case TOKEN_SEMICOLON:
case TOKEN_EOF:
return true;
default:
return false;
}
}
// === Functions
/* Parses a simple list of words (command and arguments)
* and returns the resulting ast
*/
struct ast *parse_simple_command(void)
{
struct list *cmd_elements = NULL;
char *token = pop_token();
if (token == NULL) // just in case ?
{
puts("Internal error: cannot get the following token");
return NULL;
}
struct token *token = POP_TOKEN();
while (token != NULL && !isterminator(token[0]))
while (!isterminator(token))
{
cmd_elements = list_append(cmd_elements, token);
token = pop_token();
}
if (token == NULL)
{
puts("Internal error: cannot get the following token");
return NULL;
cmd_elements = list_append(cmd_elements, token->data);
token = POP_TOKEN();
}
struct ast *result = ast_create_cmd(cmd_elements);
@ -26,10 +68,123 @@ struct ast *parse_simple_command(void)
struct ast *parse_if_rule(void)
{
return NULL;
// If condition
struct token *token = POP_TOKEN();
if (token->type != TOKEN_IF)
{
puts("Internal error: expected a if rule but token has different "
"type");
return NULL;
}
struct ast *condition_content = parse_compound_list();
// Then content
token = POP_TOKEN();
if (token->type != TOKEN_THEN)
{
puts("Expected the 'then' keyword but token has different type");
return NULL;
}
struct ast *then_content = parse_compound_list();
// Eventual else/elif clause(s)
struct ast *else_content = parse_else_clause();
token = POP_TOKEN();
if (token->type != TOKEN_FI)
{
puts("Expected the 'fi' keyword but token has different type");
// TODO free previous asts
return NULL;
}
struct ast *result =
ast_create_if(condition_content, then_content, else_content);
if (result == NULL)
{
puts("Internal error: could not create a new AST (AST_IF)");
// TODO free previous asts
return NULL;
}
return result;
}
struct ast *parse_compound_list(void)
{
struct list *result_list = NULL; // ast* list
struct list *cmd_elements = NULL; // token* list
struct token *token = PEEK_TOKEN();
while (token->type != TOKEN_THEN || token->type != TOKEN_ELIF
|| TOKEN_TYPE != TOKEN_ELSE)
{
// Parse simple command
if (token->type == TOKEN_SEMICOLON || token->type == TOKEN_NEWLINE)
{
// Stage (-> next command)
struct ast *command = ast_create_cmd(cmd_elements);
result_list = list_append(result_list, command);
cmd_elements = NULL;
}
if (token->type == TOKEN_EOF)
{
puts("Syntax error: Unexpected end of stream"); // TODO pas très
// bien dit
return NULL;
}
cmd_elements = list_append(cmd_elements, token->data);
token = POP_TOKEN();
}
struct ast *result = ast_create_list(result_list);
return result;
}
struct ast *parse_else_clause(void)
{
// Eventual elif content
token = PEEK_TOKEN();
struct ast *result = NULL;
// TODO handle ELIF
// while (token->type == TOKEN_ELIF)
// {
// puts("ABORTING ELIF: Not implemented ma gueule");
// token = POP_TOKEN(); // Forward
// }
// Eventual else content
if (token->type == TOKEN_ELSE)
{
result = parse_compound_list();
token = POP_TOKEN(); // Forward
}
if (result == NULL)
result == ast_create_void();
return result;
}
struct ast *parse_shell_command(void)
{
return parse_if_rule();
struct token *token = PEEK_TOKEN();
switch (token->type)
{
case TOKEN_IF:
return parse_if_rule();
default:
puts("I think it's not implemented yet");
return NULL;
}
}

5
src/parser/parsing_utils.h
View file

@ -11,7 +11,8 @@ struct ast *parse_if_rule(void);
*/
struct ast *parse_shell_command(void);
/*
/* @brief parses commands inside if/else clauses and returns the corresponding
* AST list
*/
struct ast* parse_compound_list(void);
@ -21,4 +22,4 @@ struct ast* parse_and_or(void);
/*
*/
struct ast* else_clause(void);
struct ast* parse_else_clause(void);