mbstring unused internal functions

5 years ago by Legale Legage — view source

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Hello.

Looking through the source code of the mbstring.c file I found a lot
of unused internal functions. It seems that this is just a bunch of
old junk.

Examples:

MBSTRING_API size_t php_mb_mbchar_bytes_ex(const char *s, const
mbfl_encoding *enc)
MBSTRING_API size_t php_mb_mbchar_bytes(const char *s)
MBSTRING_API char *php_mb_safe_strrchr(const char *s, unsigned int c,
size_t nbytes)
MBSTRING_API char *php_mb_safe_strrchr_ex(const char *s, unsigned int
c, size_t nbytes, const mbfl_encoding *enc)

5 years ago by Christoph M. Becker — view source

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Looking through the source code of the mbstring.c file I found a lot
of unused internal functions. It seems that this is just a bunch of
old junk.

Examples:

MBSTRING_API size_t php_mb_mbchar_bytes_ex(const char *s, const
mbfl_encoding *enc)
MBSTRING_API size_t php_mb_mbchar_bytes(const char *s)
MBSTRING_API char *php_mb_safe_strrchr(const char *s, unsigned int c,
size_t nbytes)
MBSTRING_API char *php_mb_safe_strrchr_ex(const char *s, unsigned int
c, size_t nbytes, const mbfl_encoding *enc)

MBSTRING_API means that these functions are exported, and are available
for other extensions. As such, they may well be used.

--
Christoph M. Becker

5 years ago by Nikita Popov — view source

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On Thu, Jan 24, 2019 at 12:21 PM Legale Legage legale.legale@gmail.com
wrote:

Hello.

Looking through the source code of the mbstring.c file I found a lot
of unused internal functions. It seems that this is just a bunch of
old junk.

Examples:

MBSTRING_API size_t php_mb_mbchar_bytes_ex(const char *s, const
mbfl_encoding *enc)
MBSTRING_API size_t php_mb_mbchar_bytes(const char *s)
MBSTRING_API char *php_mb_safe_strrchr(const char *s, unsigned int c,
size_t nbytes)
MBSTRING_API char *php_mb_safe_strrchr_ex(const char *s, unsigned int
c, size_t nbytes, const mbfl_encoding *enc)

How did you determine that these are unused? I'm seeing uses for all of
them in mbstring.c or php_mbregex.c

Nikita

5 years ago by Nikita Popov — view source

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On Thu, Jan 24, 2019 at 4:17 PM Legale Legage legale.legale@gmail.com
wrote:

Haven't checked php_mbregex.c

This one is defined in mbstring.h but not exists in mbstring.c:
php_mb_check_encoding_list()

Thanks, dropped in
https://github.com/php/php-src/commit/24085b187a7505aacb5bd76372f1522226656dd3
.

These are not used anywhere within php-src dir:
php_mb_mbchar_bytes()
php_mb_safe_strrchr()

The _ex versions are used though, so it probably doesn't make much sense to
drop these.

I think something wrong with php_mb_mbchar_bytes_ex()
As far as i understand the function returns the character length in
bytes based on the character encoding. At least for the UTF-16,
UTF-16BE,UTF-16LE encodings it returns 1 but should return 2 or 4.

I agree that this function looks really fishy. It correctly handles UTF-8
and fixed-width encodings, but for everything else it always returns a
character width of 1, which doesn't make much sense.

Nikita

On Thu, Jan 24, 2019 at 12:21 PM Legale Legage legale.legale@gmail.com
wrote:

Hello.

Looking through the source code of the mbstring.c file I found a lot
of unused internal functions. It seems that this is just a bunch of
old junk.

Examples:

MBSTRING_API size_t php_mb_mbchar_bytes_ex(const char *s, const
mbfl_encoding *enc)
MBSTRING_API size_t php_mb_mbchar_bytes(const char *s)
MBSTRING_API char *php_mb_safe_strrchr(const char *s, unsigned int c,
size_t nbytes)
MBSTRING_API char *php_mb_safe_strrchr_ex(const char *s, unsigned int
c, size_t nbytes, const mbfl_encoding *enc)

How did you determine that these are unused? I'm seeing uses for all of
them in mbstring.c or php_mbregex.c

Nikita