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refactor(lexer): now use struct instead of static var

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This commit is contained in:
Matteo Flebus 2026-01-20 18:59:40 +01:00
parent 603def1597
commit f1955f0532
2 changed files with 43 additions and 39 deletions
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67
src/lexer/lexer.c
View file

@ -10,42 +10,37 @@
#include "io_backend/io_backend.h" #include "io_backend/io_backend.h"
#include "utils/string_utils/string_utils.h" #include "utils/string_utils/string_utils.h"
static char *end_last_token; /* @brief: sets the ctx->current_token to [tok].
static ssize_t remaining_chars;
static struct token *last_token;
static struct token *current_token;
/* @brief: sets the current_token to [tok].
* this function is called by token_peek(). * this function is called by token_peek().
*/ */
static void update_current_token(struct token *tok) static void update_ctx->current_token(struct token *tok, struct lexer_context *ctx)
{ {
current_token = tok; ctx->current_token = tok;
} }
/* @brief: frees the last token and sets it to [tok]. /* @brief: frees the last token and sets it to [tok].
* Also sets current_token to NULL. * Also sets ctx->current_token to NULL.
* this function is called by token_pop(). * this function is called by token_pop().
*/ */
static void update_last_token(struct token *tok) static void update_ctx->previous_token(struct token *tok, struct lexer_context *ctx)
{ {
free_token(&last_token); free_token(&ctx->previous_token);
last_token = tok; ctx->previous_token = tok;
} }
/* @brief: updates the current position in the stream. /* @brief: updates the current position in the stream.
* [stream] += [i] * [stream] += [i]
* Also frees the last sent token, and sets it to current_token. * Also frees the last sent token, and sets it to ctx->current_token.
* Current token is then set to NULL. * Current token is then set to NULL.
* This function is called by token_pop(). * This function is called by token_pop().
*/ */
static void save_state(char *stream, ssize_t i) static void save_state(char *stream, ssize_t i, struct lexer_context *ctx)
{ {
remaining_chars -= i; ctx->remaining_chars -= i;
end_last_token = stream + i; ctx->end_ctx->previous_token = stream + i;
update_last_token(current_token); update_ctx->previous_token(ctx->current_token);
update_current_token(NULL); update_ctx->current_token(NULL);
} }
/* @return: true if a special character from the grammar was found, /* @return: true if a special character from the grammar was found,
@ -204,21 +199,21 @@ void free_token(struct token **tok)
*tok = NULL; *tok = NULL;
} }
char *stream_init(void) char *stream_init(struct lexer_context *ctx)
{ {
char *stream; char *stream;
if (last_token == NULL) // at the begining if (ctx->previous_token == NULL) // at the begining
{ {
remaining_chars = stream_read(&stream); ctx->remaining_chars = stream_read(&stream);
} }
else else
{ {
stream = end_last_token; stream = ctx->end_ctx->previous_token;
} }
char *trimed_stream = trim_blank_left(stream); char *trimed_stream = trim_blank_left(stream);
remaining_chars -= trimed_stream - stream; ctx->remaining_chars -= trimed_stream - stream;
stream = trimed_stream; stream = trimed_stream;
return stream; return stream;
@ -259,12 +254,12 @@ static bool update_lexing_mode(char *stream, ssize_t i,
return *lexing_mode != mode_before_update; return *lexing_mode != mode_before_update;
} }
struct token *peek_token(void) struct token *peek_token(struct lexer_context *ctx)
{ {
// we already created the upcoming token during the previous call to peek() // we already created the upcoming token during the previous call to peek()
if (current_token != NULL) if (ctx->current_token != NULL)
{ {
return current_token; return ctx->current_token;
} }
char *stream = stream_init(); char *stream = stream_init();
@ -273,7 +268,7 @@ struct token *peek_token(void)
// Usefull to know if we are inside a quote or double quote // Usefull to know if we are inside a quote or double quote
enum lexing_mode lexing_mode = LEXER_NORMAL; enum lexing_mode lexing_mode = LEXER_NORMAL;
while (i < remaining_chars) while (i < ctx->remaining_chars)
{ {
// true if we didn't encounter a quote of any type at stream[i] // true if we didn't encounter a quote of any type at stream[i]
// AND we are not inside quotes // AND we are not inside quotes
@ -302,17 +297,17 @@ struct token *peek_token(void)
} }
struct token *tok = new_token(stream, i); struct token *tok = new_token(stream, i);
update_current_token(tok); update_ctx->current_token(tok);
return tok; return tok;
} }
struct token *pop_token(void) struct token *pop_token(struct lexer_context *ctx)
{ {
if (current_token != NULL && current_token->type == TOKEN_EOF) if (ctx->current_token != NULL && ctx->current_token->type == TOKEN_EOF)
{ {
// we reached end of input, frees all the token still allocated. // we reached end of input, frees all the token still allocated.
free_token(&last_token); free_token(&ctx->previous_token);
free_token(&current_token); free_token(&ctx->current_token);
return NULL; return NULL;
} }
char *stream = stream_init(); char *stream = stream_init();
@ -321,7 +316,7 @@ struct token *pop_token(void)
// Usefull to know if we are inside a quote or double quote // Usefull to know if we are inside a quote or double quote
enum lexing_mode lexing_mode = LEXER_NORMAL; enum lexing_mode lexing_mode = LEXER_NORMAL;
while (i < remaining_chars) while (i < ctx->remaining_chars)
{ {
// true if we didn't encounter a quote of any type at stream[i] // true if we didn't encounter a quote of any type at stream[i]
// AND we are not inside quotes // AND we are not inside quotes
@ -351,11 +346,11 @@ struct token *pop_token(void)
// just in case peek() was not called before poping. // just in case peek() was not called before poping.
// (this should never happen) // (this should never happen)
if (current_token == NULL) if (ctx->current_token == NULL)
{ {
current_token = new_token(stream, i); ctx->current_token = new_token(stream, i);
} }
save_state(stream, i); save_state(stream, i);
return last_token; return ctx->previous_token;
} }

15
src/lexer/lexer.h
View file

@ -3,6 +3,15 @@
#include <sys/types.h> #include <sys/types.h>
struct lexer_context
{
char *end_last_token;
ssize_t remaining_chars;
struct token *last_token;
struct token *current_token;
};
enum lexing_mode enum lexing_mode
{ {
LEXER_NORMAL, LEXER_NORMAL,
@ -55,7 +64,7 @@ struct token
* @brief: returns the next (newly allocated) token without consuming it. * @brief: returns the next (newly allocated) token without consuming it.
* if end of input is reached, returns a token of type TOKEN_EOF. * if end of input is reached, returns a token of type TOKEN_EOF.
*/ */
struct token *peek_token(void); struct token *peek_token(struct lexer_context *ctx);
/* /*
* @brief: returns the next (newly allocated) token and consumes it. * @brief: returns the next (newly allocated) token and consumes it.
@ -66,7 +75,7 @@ struct token *peek_token(void);
* and returns NULL. This means that after peeking a token EOF * and returns NULL. This means that after peeking a token EOF
* in the parser, there must be EXACTLY ONE call to pop_token(). * in the parser, there must be EXACTLY ONE call to pop_token().
*/ */
struct token *pop_token(void); struct token *pop_token(struct lexer_context *ctx);
/* @note: maybe usefull for subshells. /* @note: maybe usefull for subshells.
* *
@ -96,6 +105,6 @@ void free_token(struct token **tok);
* *
* @return: char* stream from which we tokenise. * @return: char* stream from which we tokenise.
*/ */
char *stream_init(void); char *stream_init(struct lexer_context *ctx);
#endif /* ! LEXER_H */ #endif /* ! LEXER_H */