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Merge branch 'lexer' into dev

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This commit is contained in:
matteo 2026-01-17 16:26:30 +01:00
commit e80058a765
1 changed files with 82 additions and 71 deletions
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153
src/lexer/lexer.c
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@ -12,7 +12,6 @@
static char *end_last_token;
static ssize_t remaining_chars;
static bool at_beginning = true;
static struct token *last_token;
static struct token *current_token;
@ -34,17 +33,19 @@ static void update_last_token(struct token *tok)
last_token = tok;
}
/* @brief: saves state for the next call to the the lexer.
* this function is called by token_pop().
*
/* @brief: updates the current position in the stream.
* [stream] += [i]
* Also frees the last sent token, and sets it to current_token.
* Current token is then set to NULL.
* This function is called by token_pop().
*/
static void save_state(char *stream, ssize_t i, struct token *tok)
static void save_state(char *stream, ssize_t i)
{
remaining_chars -= i;
end_last_token = stream + i;
at_beginning = false;
update_last_token(tok);
update_last_token(current_token);
update_current_token(NULL);
}
/* @return: true if a special character from the grammar was found,
@ -68,62 +69,62 @@ static void set_token_spechar(struct token *tok, char *begin, ssize_t size)
return;
switch (begin[0])
{
case EOF:
tok->type = TOKEN_EOF;
break;
case ';':
tok->type = TOKEN_SEMICOLON;
break;
case '\n':
tok->type = TOKEN_NEWLINE;
break;
case '\'':
tok->type = TOKEN_QUOTE;
break;
case '"':
tok->type = TOKEN_DOUBLE_QUOTE;
break;
case '`':
tok->type = TOKEN_GRAVE;
break;
case '#':
tok->type = TOKEN_COMMENT;
break;
case '|':
tok->type = TOKEN_PIPE;
break;
case '&':
tok->type = TOKEN_AMPERSAND;
break;
case '\\':
tok->type = TOKEN_BACKSLASH;
break;
case '$':
tok->type = TOKEN_DOLLAR;
break;
case '(':
tok->type = TOKEN_LEFT_PAREN;
break;
case ')':
tok->type = TOKEN_RIGHT_PAREN;
break;
case '{':
tok->type = TOKEN_LEFT_BRACKET;
break;
case '}':
tok->type = TOKEN_RIGHT_BRACKET;
break;
case '<':
tok->type = TOKEN_LESS;
break;
case '>':
tok->type = TOKEN_GREATER;
break;
case '*':
tok->type = TOKEN_STAR;
break;
default:
break;
case EOF:
tok->type = TOKEN_EOF;
break;
case ';':
tok->type = TOKEN_SEMICOLON;
break;
case '\n':
tok->type = TOKEN_NEWLINE;
break;
case '\'':
tok->type = TOKEN_QUOTE;
break;
case '"':
tok->type = TOKEN_DOUBLE_QUOTE;
break;
case '`':
tok->type = TOKEN_GRAVE;
break;
case '#':
tok->type = TOKEN_COMMENT;
break;
case '|':
tok->type = TOKEN_PIPE;
break;
case '&':
tok->type = TOKEN_AMPERSAND;
break;
case '\\':
tok->type = TOKEN_BACKSLASH;
break;
case '$':
tok->type = TOKEN_DOLLAR;
break;
case '(':
tok->type = TOKEN_LEFT_PAREN;
break;
case ')':
tok->type = TOKEN_RIGHT_PAREN;
break;
case '{':
tok->type = TOKEN_LEFT_BRACKET;
break;
case '}':
tok->type = TOKEN_RIGHT_BRACKET;
break;
case '<':
tok->type = TOKEN_LESS;
break;
case '>':
tok->type = TOKEN_GREATER;
break;
case '*':
tok->type = TOKEN_STAR;
break;
default:
break;
}
}
@ -155,6 +156,10 @@ static void set_token_keyword(struct token *tok, char *begin, ssize_t size)
tok->type = TOKEN_ELIF;
}
// no keywords found.
if (tok->type == TOKEN_NULL)
return;
tok->data = calloc(size + 1, sizeof(char));
if (tok->data == NULL)
return;
@ -203,10 +208,9 @@ char *stream_init(void)
{
char *stream;
if (at_beginning)
if (last_token == NULL) // at the begining
{
remaining_chars = stream_read(&stream);
// at_beginning = true;
}
else
{
@ -222,8 +226,8 @@ char *stream_init(void)
struct token *peek_token(void)
{
// EOF looping mode
if (current_token != NULL && current_token->type == TOKEN_EOF)
// we already created the upcoming token during the previous call to peek()
if (current_token != NULL)
{
return current_token;
}
@ -254,9 +258,11 @@ struct token *peek_token(void)
struct token *pop_token(void)
{
if (last_token != NULL && last_token->type == TOKEN_EOF)
if (current_token != NULL && current_token->type == TOKEN_EOF)
{
// we reached end of input, frees all the token still allocated.
free_token(&last_token);
free_token(&current_token);
return NULL;
}
char *stream = stream_init();
@ -278,8 +284,13 @@ struct token *pop_token(void)
i++;
}
struct token *tok = new_token(stream, i);
save_state(stream, i, tok);
// just in case peek() was not called before poping.
// (this should never happen)
if (current_token == NULL)
{
current_token = new_token(stream, i);
}
save_state(stream, i);
return tok;
return last_token;
}