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/**
* @file pm_strpbrk.h
*
* A custom strpbrk implementation.
*/
#ifndef PRISM_STRPBRK_H
#define PRISM_STRPBRK_H
#include "prism/defines.h"
#include "prism/parser.h"
#include <stddef.h>
#include <string.h>
/**
* Here we have rolled our own version of strpbrk. The standard library strpbrk
* has undefined behavior when the source string is not null-terminated. We want
* to support strings that are not null-terminated because pm_parse does not
* have the contract that the string is null-terminated. (This is desirable
* because it means the extension can call pm_parse with the result of a call to
* mmap).
*
* The standard library strpbrk also does not support passing a maximum length
* to search. We want to support this for the reason mentioned above, but we
* also don't want it to stop on null bytes. Ruby actually allows null bytes
* within strings, comments, regular expressions, etc. So we need to be able to
* skip past them.
*
* Finally, we want to support encodings wherein the charset could contain
* characters that are trailing bytes of multi-byte characters. For example, in
* Shift-JIS, the backslash character can be a trailing byte. In that case we
* need to take a slower path and iterate one multi-byte character at a time.
*
* @param parser The parser.
* @param source The source to search.
* @param charset The charset to search for.
* @param length The maximum number of bytes to search.
* @return A pointer to the first character in the source string that is in the
* charset, or NULL if no such character exists.
*/
const uint8_t * pm_strpbrk(const pm_parser_t *parser, const uint8_t *source, const uint8_t *charset, ptrdiff_t length);
#endif
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