Merge branch 'parser' into dev (keeping parser)

This commit is contained in:
Matteo Flebus 2026-01-19 19:37:59 +01:00
commit f38e828c0a
2 changed files with 267 additions and 115 deletions

View file

@ -1,4 +1,5 @@
#define _POSIX_C_SOURCE 200809L
// === Includes
#include "parsing_utils.h"
@ -13,7 +14,7 @@
// === Static functions
/* Returns true if c is a command terminator, false otherwise
*/
*/
static bool isterminator(struct token *token)
{
if (token == NULL)
@ -21,17 +22,20 @@ static bool isterminator(struct token *token)
switch (token->type)
{
case TOKEN_NEWLINE:
case TOKEN_SEMICOLON:
case TOKEN_EOF:
return true;
default:
return false;
case TOKEN_NEWLINE:
case TOKEN_SEMICOLON:
case TOKEN_EOF:
return true;
default:
return false;
}
}
/* @brief: returns true if token is an end of list indicator.
* @warning: not used
*/
/*
static bool is_end_of_list(struct token *token)
{
if (token == NULL)
@ -39,34 +43,20 @@ static bool is_end_of_list(struct token *token)
switch (token->type)
{
case TOKEN_NEWLINE:
case TOKEN_EOF:
return true;
default:
return false;
case TOKEN_NEWLINE:
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 ast *parse_input(void)
{
struct list *command_elements = NULL;
struct token *token = PEEK_TOKEN();
while (!isterminator(token))
{
token = POP_TOKEN();
char *word = strdup(token->data);
command_elements = list_append(command_elements, word);
token = PEEK_TOKEN();
}
struct ast *result = ast_create_command(command_elements);
return result;
return parse_list();
}
struct ast *parse_list(void)
@ -76,57 +66,139 @@ struct ast *parse_list(void)
struct token *token = PEEK_TOKEN();
while (!is_end_of_list(token))
// and_or
current_node = parse_and_or();
if (current_node == NULL)
return NULL;
list_append(result_list, current_node);
// Following and_or commands
token = PEEK_TOKEN();
while (token->type == TOKEN_SEMICOLON)
{
if (token->type == TOKEN_SEMICOLON)
token = POP_TOKEN();
if (!isterminator(token)) // Follow(list)
{
result_list = list_append(result_list, current_node);
current_node = parse_and_or();
if (current_node == NULL)
{
//TODO free list
// There must be a function for that
return NULL;
}
list_append(result_list, current_node);
token = PEEK_TOKEN();
}
else
{
// TODO use parse_and_or() instead.
current_node = parse_simple_command();
}
token = PEEK_TOKEN();
}
result_list = list_append(result_list, current_node);
return ast_create_list(result_list);
}
struct ast *parse_if_rule(void)
struct ast *parse_and_or(void)
{
// If condition
struct token *token = POP_TOKEN();
return parse_pipeline();
}
if (token->type != TOKEN_IF)
struct ast *parse_pipeline(void)
{
return parse_command();
}
struct ast *parse_command(void)
{
struct token *token = PEEK_TOKEN();
if (token->type == TOKEN_WORD)
{
puts("Internal error: expected a if rule but token has different "
"type");
return parse_simple_command();
}
else if (token->type == TOKEN_IF)
{
return parse_shell_command();
}
else
{
return ast_create_void(); // TODO not sure what to do
}
}
struct ast *parse_simple_command(void)
{
struct list *command_elements = NULL;
struct token *token = PEEK_TOKEN();
if (token->type != TOKEN_WORD)
{
puts("Expected a command but got a different token type");
return NULL;
}
while (token->type == TOKEN_WORD)
{
token = POP_TOKEN();
char* word = strdup(token->data);
command_elements = list_append(command_elements, word);
token = PEEK_TOKEN();
}
struct ast *result = ast_create_command(command_elements);
return result;
}
// TODO check compliance with the grammar
struct ast *parse_shell_command(void)
{
return parse_if_rule();
}
struct ast *parse_if_rule(void)
{
// If keyword
struct token *token = POP_TOKEN();
if (token->type != TOKEN_IF)
{
puts("Internal error: expected a if rule but token has different "
"type");
return NULL;
}
// Condition content
struct ast *condition_content = parse_compound_list();
// Then content
// Then keyword
token = POP_TOKEN();
if (token->type != TOKEN_THEN)
{
ast_free(&condition_content);
puts("Expected the 'then' keyword but token has different type");
return NULL;
}
// Then content
struct ast *then_content = parse_compound_list();
if (then_content == NULL)
{
ast_free(&condition_content);
ast_free(&then_content);
return NULL;
}
// Eventual else/elif clause(s)
struct ast *else_content = parse_else_clause();
if (else_content == NULL)
{
ast_free(&condition_content);
ast_free(&then_content);
return NULL;
}
token = POP_TOKEN();
if (token->type != TOKEN_FI)
{
ast_free(&condition_content);
ast_free(&then_content);
ast_free(&else_content);
puts("Expected the 'fi' keyword but token has different type");
// TODO free previous asts
return NULL;
}
@ -134,8 +206,10 @@ struct ast *parse_if_rule(void)
ast_create_if(condition_content, then_content, else_content);
if (result == NULL)
{
ast_free(&condition_content);
ast_free(&then_content);
ast_free(&else_content);
puts("Internal error: could not create a new AST (AST_IF)");
// TODO free previous asts
return NULL;
}
@ -145,53 +219,98 @@ struct ast *parse_if_rule(void)
struct ast *parse_compound_list(void)
{
struct list *result_list = NULL; // ast* list
struct list *command_elements = NULL; // token* list
struct ast *current_cmd = NULL;
struct token *token = PEEK_TOKEN();
while (token->type != TOKEN_THEN || token->type != TOKEN_ELIF
|| token->type != TOKEN_ELSE)
// Skip newlines
while (token->type == TOKEN_NEWLINE)
{
// Parse simple command
if (token->type == TOKEN_SEMICOLON || token->type == TOKEN_NEWLINE)
{
// Stage (-> next command)
struct ast *command = ast_create_command(command_elements);
result_list = list_append(result_list, command);
command_elements = NULL;
}
if (token->type == TOKEN_EOF)
{
puts("Syntax error: Unexpected end of stream"); // TODO pas très
// bien dit
return NULL;
}
char *word = strdup(token->data);
command_elements = list_append(command_elements, word);
token = POP_TOKEN();
}
// and_or
current_cmd = parse_and_or();
if (current_cmd == NULL)
return NULL;
list_append(result_list, current_cmd);
// Following commands
token = PEEK_TOKEN();
while (token->type == TOKEN_SEMICOLON || token->type == TOKEN_NEWLINE)
{
POP_TOKEN();
// Skip newlines
while (token->type == TOKEN_NEWLINE)
{
token = POP_TOKEN();
}
// and_or
current_cmd = parse_and_or();
if (current_cmd == NULL)
return NULL;
list_append(result_list, current_cmd);
token = PEEK_TOKEN();
}
// Eventual semicolons
if (token->type == TOKEN_SEMICOLON)
{
token = POP_TOKEN();
}
// Skip newlines
while (token->type == TOKEN_NEWLINE)
{
token = POP_TOKEN();
}
struct ast *result = ast_create_list(result_list);
return result;
}
struct ast *parse_else_clause(void)
{
// Eventual elif content
struct token *token = PEEK_TOKEN();
// Eventual elif content
while (token->type == TOKEN_ELIF)
{
// Condition
token = POP_TOKEN();
struct ast *condition = parse_compound_list();
// 'then'
token = POP_TOKEN();
if (token->type != TOKEN_THEN)
{
puts("Expected the 'then' keyword but got a different token type");
return NULL;
}
// Then clause
struct ast *then_content = parse_compound_list();
// Eventual else clause (recursive)
struct ast *else_content = NULL;
token = PEEK_TOKEN();
if (token->type == TOKEN_ELSE || token->type == TOKEN_ELIF)
{
else_content = parse_else_clause();
}
struct ast *result =
ast_create_if(condition, then_content, else_content);
return result;
}
// Eventual else content
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();
@ -203,18 +322,3 @@ struct ast *parse_else_clause(void)
return result;
}
struct ast *parse_shell_command(void)
{
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;
}
}

View file

@ -19,33 +19,81 @@
return NULL; \
}
/* @brief: parses a list of [and_or] rules, separated by semicolons.
/* @brief Acts as the entry point of the parser, calls parse_list
*
* @code input = list '\n'
* | list EOF
* | '\n'
* | EOF
* ;
*/
struct ast* parse_input(void);
/* @brief: parses a list of [and_or] rules separated by semicolons and that
* ends by a newline
*
* @code list = and_or { ';' and_or } [ ';' ] ;
*/
struct ast *parse_list(void);
/* @brief Parses a simple list of words (command and arguments)
* and returns the resulting ast
*/
struct ast *parse_simple_command(void);
/*
*/
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);
/*
/* @brief Only parses a pipeline rule for the moment
*
* @code and_or = pipeline ;
*/
struct ast *parse_and_or(void);
/*
/* @brief Only parses a command rule for the moment
*
* @code pipeline = command ;
*/
struct ast* parse_pipeline(void);
/* @brief Parses a simple command rule or a shell command rule depending on
* the first token.
* @note
* TOKEN_WORD => simple_command
* TOKEN_IF => shell_command
*
* @code command = simple_command
* | shell_command
* ;
*/
struct ast* parse_command(void);
/* @brief Parses a simple list of words (command and arguments)
* ending by a separator
*
* @code simple_command = WORD { element } ;
*/
struct ast *parse_simple_command(void);
/* @brief Only parses if rules for the moment
*
* @code shell_command = if_rule ;
*/
struct ast *parse_shell_command(void);
/* @brief Parses a if rule (condition, then-clause, elif-clause, else-clause)
*
* @code if_rule = 'if' compound_list 'then' compound_list [else_clause] 'fi' ;
*/
struct ast *parse_if_rule(void);
/* @brief parses commands inside if/else clauses and returns the corresponding
* AST list
*
* @code compound_list = {'\n'} and_or { ( ';' | '\n' ) {'\n'} and_or } [';'] {'\n'} ;
*/
struct ast* parse_compound_list(void);
/* @brief
*
* @code else_clause = 'else' compound_list
* | 'elif' compound_list 'then' compound_list [else_clause]
* ;
*/
struct ast *parse_else_clause(void);