#ifndef Py_HASH_H
#define Py_HASH_H
#ifdef __cplusplus
extern "C" {
#endif
/* Cutoff for small string DJBX33A optimization in range [1, cutoff).
*
* About 50% of the strings in a typical Python application are smaller than
* 6 to 7 chars. However DJBX33A is vulnerable to hash collision attacks.
* NEVER use DJBX33A for long strings!
*
* A Py_HASH_CUTOFF of 0 disables small string optimization. 32 bit platforms
* should use a smaller cutoff because it is easier to create colliding
* strings. A cutoff of 7 on 64bit platforms and 5 on 32bit platforms should
* provide a decent safety margin.
*/
#ifndef Py_HASH_CUTOFF
# define Py_HASH_CUTOFF 0
#elif (Py_HASH_CUTOFF > 7 || Py_HASH_CUTOFF < 0)
# error Py_HASH_CUTOFF must in range 0...7.
#endif /* Py_HASH_CUTOFF */
/* Hash algorithm selection
*
* The values for Py_HASH_* are hard-coded in the
* configure script.
*
* - FNV and SIPHASH* are available on all platforms and architectures.
* - With EXTERNAL embedders can provide an alternative implementation with::
*
* PyHash_FuncDef PyHash_Func = {...};
*
* XXX: Figure out __declspec() for extern PyHash_FuncDef.
*/
#define Py_HASH_EXTERNAL 0
#define Py_HASH_SIPHASH24 1
#define Py_HASH_FNV 2
#define Py_HASH_SIPHASH13 3
#ifndef Py_HASH_ALGORITHM
# ifndef HAVE_ALIGNED_REQUIRED
# define Py_HASH_ALGORITHM Py_HASH_SIPHASH13
# else
# define Py_HASH_ALGORITHM Py_HASH_FNV
# endif /* uint64_t && uint32_t && aligned */
#endif /* Py_HASH_ALGORITHM */
#ifndef Py_LIMITED_API
# define Py_CPYTHON_HASH_H
# include "cpython/pyhash.h"
# undef Py_CPYTHON_HASH_H
#endif
#ifdef __cplusplus
}
#endif
#endif // !Py_HASH_H
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