Change mbstring values from size_t to ptrdiff_t as that's what they return

[Girgias]

As this has emerged out of #5151 that this may be a bug.

Oniguruma is returning a ptrdiff_t but we were storing it in a size_t but a ptrdiff_t may be negative.

[nikic]

I would suggest to use the actual OnigWhatever type here, even if it typedefs to ptrdiff_t.

[Girgias]

I would suggest to use the actual OnigWhatever type here, even if it typedefs to ptrdiff_t.

Well there isn't really a typedef from what I saw:

beg and end are fetched from the MBREX(search_regs) which is defined as a OnigRegion as can be seen here:

struct _zend_mb_regex_globals {
	OnigEncoding default_mbctype;
	OnigEncoding current_mbctype;
	HashTable ht_rc;
	zval search_str;
	zval *search_str_val;
	size_t search_pos;
	php_mb_regex_t *search_re;
	OnigRegion *search_regs;
	OnigOptionType regex_default_options;
	OnigSyntaxType *regex_default_syntax;
};

(see: https://php-lxr.adamharvey.name/source/xref/master/ext/mbstring/php_mbregex.c#63)

And OnigRegion is a typedef to the re_registers struct which is as following:

struct re_registers {
  int  allocated;
  int  num_regs;
  int* beg;
  int* end;
  /* extended */
  OnigCaptureTreeNode* history_root;  /* capture history tree root */
};

(See https://github.com/kkos/oniguruma/blob/master/src/oniguruma.h#L652 and line 670)

And from what I saw in oniguruma.h all the typedefs are unsigned int or unsigned char

[nikic]

Thanks for the reference. In that case, shouldn't the type be int rather than ptrdiff_t?

[Girgias]

Thanks for the reference. In that case, shouldn't the type be int rather than ptrdiff_t?

Indeed that would make more sense, I looked into it after you wanted me to change it to OnigSomething so I was trying to figure out what they were. :)