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authormonster <monster@ydb.tech>2022-07-07 14:41:37 +0300
committermonster <monster@ydb.tech>2022-07-07 14:41:37 +0300
commit06e5c21a835c0e923506c4ff27929f34e00761c2 (patch)
tree75efcbc6854ef9bd476eb8bf00cc5c900da436a2 /contrib/tools/python3/src/Python/pyhash.c
parent03f024c4412e3aa613bb543cf1660176320ba8f4 (diff)
downloadydb-06e5c21a835c0e923506c4ff27929f34e00761c2.tar.gz
fix ya.make
Diffstat (limited to 'contrib/tools/python3/src/Python/pyhash.c')
-rw-r--r--contrib/tools/python3/src/Python/pyhash.c443
1 files changed, 0 insertions, 443 deletions
diff --git a/contrib/tools/python3/src/Python/pyhash.c b/contrib/tools/python3/src/Python/pyhash.c
deleted file mode 100644
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--- a/contrib/tools/python3/src/Python/pyhash.c
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@@ -1,443 +0,0 @@
-/* Set of hash utility functions to help maintaining the invariant that
- if a==b then hash(a)==hash(b)
-
- All the utility functions (_Py_Hash*()) return "-1" to signify an error.
-*/
-#include "Python.h"
-
-#ifdef __APPLE__
-# include <libkern/OSByteOrder.h>
-#elif defined(HAVE_LE64TOH) && defined(HAVE_ENDIAN_H)
-# include <endian.h>
-#elif defined(HAVE_LE64TOH) && defined(HAVE_SYS_ENDIAN_H)
-# include <sys/endian.h>
-#endif
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-_Py_HashSecret_t _Py_HashSecret = {{0}};
-
-#if Py_HASH_ALGORITHM == Py_HASH_EXTERNAL
-extern PyHash_FuncDef PyHash_Func;
-#else
-static PyHash_FuncDef PyHash_Func;
-#endif
-
-/* Count _Py_HashBytes() calls */
-#ifdef Py_HASH_STATS
-#define Py_HASH_STATS_MAX 32
-static Py_ssize_t hashstats[Py_HASH_STATS_MAX + 1] = {0};
-#endif
-
-/* For numeric types, the hash of a number x is based on the reduction
- of x modulo the prime P = 2**_PyHASH_BITS - 1. It's designed so that
- hash(x) == hash(y) whenever x and y are numerically equal, even if
- x and y have different types.
-
- A quick summary of the hashing strategy:
-
- (1) First define the 'reduction of x modulo P' for any rational
- number x; this is a standard extension of the usual notion of
- reduction modulo P for integers. If x == p/q (written in lowest
- terms), the reduction is interpreted as the reduction of p times
- the inverse of the reduction of q, all modulo P; if q is exactly
- divisible by P then define the reduction to be infinity. So we've
- got a well-defined map
-
- reduce : { rational numbers } -> { 0, 1, 2, ..., P-1, infinity }.
-
- (2) Now for a rational number x, define hash(x) by:
-
- reduce(x) if x >= 0
- -reduce(-x) if x < 0
-
- If the result of the reduction is infinity (this is impossible for
- integers, floats and Decimals) then use the predefined hash value
- _PyHASH_INF for x >= 0, or -_PyHASH_INF for x < 0, instead.
- _PyHASH_INF and -_PyHASH_INF are also used for the
- hashes of float and Decimal infinities.
-
- NaNs hash with a pointer hash. Having distinct hash values prevents
- catastrophic pileups from distinct NaN instances which used to always
- have the same hash value but would compare unequal.
-
- A selling point for the above strategy is that it makes it possible
- to compute hashes of decimal and binary floating-point numbers
- efficiently, even if the exponent of the binary or decimal number
- is large. The key point is that
-
- reduce(x * y) == reduce(x) * reduce(y) (modulo _PyHASH_MODULUS)
-
- provided that {reduce(x), reduce(y)} != {0, infinity}. The reduction of a
- binary or decimal float is never infinity, since the denominator is a power
- of 2 (for binary) or a divisor of a power of 10 (for decimal). So we have,
- for nonnegative x,
-
- reduce(x * 2**e) == reduce(x) * reduce(2**e) % _PyHASH_MODULUS
-
- reduce(x * 10**e) == reduce(x) * reduce(10**e) % _PyHASH_MODULUS
-
- and reduce(10**e) can be computed efficiently by the usual modular
- exponentiation algorithm. For reduce(2**e) it's even better: since
- P is of the form 2**n-1, reduce(2**e) is 2**(e mod n), and multiplication
- by 2**(e mod n) modulo 2**n-1 just amounts to a rotation of bits.
-
- */
-
-Py_hash_t _Py_HashPointer(const void *);
-
-Py_hash_t
-_Py_HashDouble(PyObject *inst, double v)
-{
- int e, sign;
- double m;
- Py_uhash_t x, y;
-
- if (!Py_IS_FINITE(v)) {
- if (Py_IS_INFINITY(v))
- return v > 0 ? _PyHASH_INF : -_PyHASH_INF;
- else
- return _Py_HashPointer(inst);
- }
-
- m = frexp(v, &e);
-
- sign = 1;
- if (m < 0) {
- sign = -1;
- m = -m;
- }
-
- /* process 28 bits at a time; this should work well both for binary
- and hexadecimal floating point. */
- x = 0;
- while (m) {
- x = ((x << 28) & _PyHASH_MODULUS) | x >> (_PyHASH_BITS - 28);
- m *= 268435456.0; /* 2**28 */
- e -= 28;
- y = (Py_uhash_t)m; /* pull out integer part */
- m -= y;
- x += y;
- if (x >= _PyHASH_MODULUS)
- x -= _PyHASH_MODULUS;
- }
-
- /* adjust for the exponent; first reduce it modulo _PyHASH_BITS */
- e = e >= 0 ? e % _PyHASH_BITS : _PyHASH_BITS-1-((-1-e) % _PyHASH_BITS);
- x = ((x << e) & _PyHASH_MODULUS) | x >> (_PyHASH_BITS - e);
-
- x = x * sign;
- if (x == (Py_uhash_t)-1)
- x = (Py_uhash_t)-2;
- return (Py_hash_t)x;
-}
-
-Py_hash_t
-_Py_HashPointerRaw(const void *p)
-{
- size_t y = (size_t)p;
- /* bottom 3 or 4 bits are likely to be 0; rotate y by 4 to avoid
- excessive hash collisions for dicts and sets */
- y = (y >> 4) | (y << (8 * SIZEOF_VOID_P - 4));
- return (Py_hash_t)y;
-}
-
-Py_hash_t
-_Py_HashPointer(const void *p)
-{
- Py_hash_t x = _Py_HashPointerRaw(p);
- if (x == -1) {
- x = -2;
- }
- return x;
-}
-
-Py_hash_t
-_Py_HashBytes(const void *src, Py_ssize_t len)
-{
- Py_hash_t x;
- /*
- We make the hash of the empty string be 0, rather than using
- (prefix ^ suffix), since this slightly obfuscates the hash secret
- */
- if (len == 0) {
- return 0;
- }
-
-#ifdef Py_HASH_STATS
- hashstats[(len <= Py_HASH_STATS_MAX) ? len : 0]++;
-#endif
-
-#if Py_HASH_CUTOFF > 0
- if (len < Py_HASH_CUTOFF) {
- /* Optimize hashing of very small strings with inline DJBX33A. */
- Py_uhash_t hash;
- const unsigned char *p = src;
- hash = 5381; /* DJBX33A starts with 5381 */
-
- switch(len) {
- /* ((hash << 5) + hash) + *p == hash * 33 + *p */
- case 7: hash = ((hash << 5) + hash) + *p++; /* fallthrough */
- case 6: hash = ((hash << 5) + hash) + *p++; /* fallthrough */
- case 5: hash = ((hash << 5) + hash) + *p++; /* fallthrough */
- case 4: hash = ((hash << 5) + hash) + *p++; /* fallthrough */
- case 3: hash = ((hash << 5) + hash) + *p++; /* fallthrough */
- case 2: hash = ((hash << 5) + hash) + *p++; /* fallthrough */
- case 1: hash = ((hash << 5) + hash) + *p++; break;
- default:
- Py_UNREACHABLE();
- }
- hash ^= len;
- hash ^= (Py_uhash_t) _Py_HashSecret.djbx33a.suffix;
- x = (Py_hash_t)hash;
- }
- else
-#endif /* Py_HASH_CUTOFF */
- x = PyHash_Func.hash(src, len);
-
- if (x == -1)
- return -2;
- return x;
-}
-
-void
-_PyHash_Fini(void)
-{
-#ifdef Py_HASH_STATS
- fprintf(stderr, "len calls total\n");
- Py_ssize_t total = 0;
- for (int i = 1; i <= Py_HASH_STATS_MAX; i++) {
- total += hashstats[i];
- fprintf(stderr, "%2i %8zd %8zd\n", i, hashstats[i], total);
- }
- total += hashstats[0];
- fprintf(stderr, "> %8zd %8zd\n", hashstats[0], total);
-#endif
-}
-
-PyHash_FuncDef *
-PyHash_GetFuncDef(void)
-{
- return &PyHash_Func;
-}
-
-/* Optimized memcpy() for Windows */
-#ifdef _MSC_VER
-# if SIZEOF_PY_UHASH_T == 4
-# define PY_UHASH_CPY(dst, src) do { \
- dst[0] = src[0]; dst[1] = src[1]; dst[2] = src[2]; dst[3] = src[3]; \
- } while(0)
-# elif SIZEOF_PY_UHASH_T == 8
-# define PY_UHASH_CPY(dst, src) do { \
- dst[0] = src[0]; dst[1] = src[1]; dst[2] = src[2]; dst[3] = src[3]; \
- dst[4] = src[4]; dst[5] = src[5]; dst[6] = src[6]; dst[7] = src[7]; \
- } while(0)
-# else
-# error SIZEOF_PY_UHASH_T must be 4 or 8
-# endif /* SIZEOF_PY_UHASH_T */
-#else /* not Windows */
-# define PY_UHASH_CPY(dst, src) memcpy(dst, src, SIZEOF_PY_UHASH_T)
-#endif /* _MSC_VER */
-
-
-#if Py_HASH_ALGORITHM == Py_HASH_FNV
-/* **************************************************************************
- * Modified Fowler-Noll-Vo (FNV) hash function
- */
-static Py_hash_t
-fnv(const void *src, Py_ssize_t len)
-{
- const unsigned char *p = src;
- Py_uhash_t x;
- Py_ssize_t remainder, blocks;
- union {
- Py_uhash_t value;
- unsigned char bytes[SIZEOF_PY_UHASH_T];
- } block;
-
-#ifdef Py_DEBUG
- assert(_Py_HashSecret_Initialized);
-#endif
- remainder = len % SIZEOF_PY_UHASH_T;
- if (remainder == 0) {
- /* Process at least one block byte by byte to reduce hash collisions
- * for strings with common prefixes. */
- remainder = SIZEOF_PY_UHASH_T;
- }
- blocks = (len - remainder) / SIZEOF_PY_UHASH_T;
-
- x = (Py_uhash_t) _Py_HashSecret.fnv.prefix;
- x ^= (Py_uhash_t) *p << 7;
- while (blocks--) {
- PY_UHASH_CPY(block.bytes, p);
- x = (_PyHASH_MULTIPLIER * x) ^ block.value;
- p += SIZEOF_PY_UHASH_T;
- }
- /* add remainder */
- for (; remainder > 0; remainder--)
- x = (_PyHASH_MULTIPLIER * x) ^ (Py_uhash_t) *p++;
- x ^= (Py_uhash_t) len;
- x ^= (Py_uhash_t) _Py_HashSecret.fnv.suffix;
- if (x == (Py_uhash_t) -1) {
- x = (Py_uhash_t) -2;
- }
- return x;
-}
-
-static PyHash_FuncDef PyHash_Func = {fnv, "fnv", 8 * SIZEOF_PY_HASH_T,
- 16 * SIZEOF_PY_HASH_T};
-
-#endif /* Py_HASH_ALGORITHM == Py_HASH_FNV */
-
-
-/* **************************************************************************
- <MIT License>
- Copyright (c) 2013 Marek Majkowski <marek@popcount.org>
-
- Permission is hereby granted, free of charge, to any person obtaining a copy
- of this software and associated documentation files (the "Software"), to deal
- in the Software without restriction, including without limitation the rights
- to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- copies of the Software, and to permit persons to whom the Software is
- furnished to do so, subject to the following conditions:
-
- The above copyright notice and this permission notice shall be included in
- all copies or substantial portions of the Software.
-
- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- THE SOFTWARE.
- </MIT License>
-
- Original location:
- https://github.com/majek/csiphash/
-
- Solution inspired by code from:
- Samuel Neves (supercop/crypto_auth/siphash24/little)
- djb (supercop/crypto_auth/siphash24/little2)
- Jean-Philippe Aumasson (https://131002.net/siphash/siphash24.c)
-
- Modified for Python by Christian Heimes:
- - C89 / MSVC compatibility
- - _rotl64() on Windows
- - letoh64() fallback
-*/
-
-/* byte swap little endian to host endian
- * Endian conversion not only ensures that the hash function returns the same
- * value on all platforms. It is also required to for a good dispersion of
- * the hash values' least significant bits.
- */
-#if PY_LITTLE_ENDIAN
-# define _le64toh(x) ((uint64_t)(x))
-#elif defined(__APPLE__)
-# define _le64toh(x) OSSwapLittleToHostInt64(x)
-#elif defined(HAVE_LETOH64)
-# define _le64toh(x) le64toh(x)
-#else
-# define _le64toh(x) (((uint64_t)(x) << 56) | \
- (((uint64_t)(x) << 40) & 0xff000000000000ULL) | \
- (((uint64_t)(x) << 24) & 0xff0000000000ULL) | \
- (((uint64_t)(x) << 8) & 0xff00000000ULL) | \
- (((uint64_t)(x) >> 8) & 0xff000000ULL) | \
- (((uint64_t)(x) >> 24) & 0xff0000ULL) | \
- (((uint64_t)(x) >> 40) & 0xff00ULL) | \
- ((uint64_t)(x) >> 56))
-#endif
-
-
-#ifdef _MSC_VER
-# define ROTATE(x, b) _rotl64(x, b)
-#else
-# define ROTATE(x, b) (uint64_t)( ((x) << (b)) | ( (x) >> (64 - (b))) )
-#endif
-
-#define HALF_ROUND(a,b,c,d,s,t) \
- a += b; c += d; \
- b = ROTATE(b, s) ^ a; \
- d = ROTATE(d, t) ^ c; \
- a = ROTATE(a, 32);
-
-#define DOUBLE_ROUND(v0,v1,v2,v3) \
- HALF_ROUND(v0,v1,v2,v3,13,16); \
- HALF_ROUND(v2,v1,v0,v3,17,21); \
- HALF_ROUND(v0,v1,v2,v3,13,16); \
- HALF_ROUND(v2,v1,v0,v3,17,21);
-
-
-static uint64_t
-siphash24(uint64_t k0, uint64_t k1, const void *src, Py_ssize_t src_sz) {
- uint64_t b = (uint64_t)src_sz << 56;
- const uint8_t *in = (const uint8_t*)src;
-
- uint64_t v0 = k0 ^ 0x736f6d6570736575ULL;
- uint64_t v1 = k1 ^ 0x646f72616e646f6dULL;
- uint64_t v2 = k0 ^ 0x6c7967656e657261ULL;
- uint64_t v3 = k1 ^ 0x7465646279746573ULL;
-
- uint64_t t;
- uint8_t *pt;
-
- while (src_sz >= 8) {
- uint64_t mi;
- memcpy(&mi, in, sizeof(mi));
- mi = _le64toh(mi);
- in += sizeof(mi);
- src_sz -= sizeof(mi);
- v3 ^= mi;
- DOUBLE_ROUND(v0,v1,v2,v3);
- v0 ^= mi;
- }
-
- t = 0;
- pt = (uint8_t *)&t;
- switch (src_sz) {
- case 7: pt[6] = in[6]; /* fall through */
- case 6: pt[5] = in[5]; /* fall through */
- case 5: pt[4] = in[4]; /* fall through */
- case 4: memcpy(pt, in, sizeof(uint32_t)); break;
- case 3: pt[2] = in[2]; /* fall through */
- case 2: pt[1] = in[1]; /* fall through */
- case 1: pt[0] = in[0]; /* fall through */
- }
- b |= _le64toh(t);
-
- v3 ^= b;
- DOUBLE_ROUND(v0,v1,v2,v3);
- v0 ^= b;
- v2 ^= 0xff;
- DOUBLE_ROUND(v0,v1,v2,v3);
- DOUBLE_ROUND(v0,v1,v2,v3);
-
- /* modified */
- t = (v0 ^ v1) ^ (v2 ^ v3);
- return t;
-}
-
-uint64_t
-_Py_KeyedHash(uint64_t key, const void *src, Py_ssize_t src_sz)
-{
- return siphash24(key, 0, src, src_sz);
-}
-
-
-#if Py_HASH_ALGORITHM == Py_HASH_SIPHASH24
-static Py_hash_t
-pysiphash(const void *src, Py_ssize_t src_sz) {
- return (Py_hash_t)siphash24(
- _le64toh(_Py_HashSecret.siphash.k0), _le64toh(_Py_HashSecret.siphash.k1),
- src, src_sz);
-}
-
-static PyHash_FuncDef PyHash_Func = {pysiphash, "siphash24", 64, 128};
-#endif
-
-#ifdef __cplusplus
-}
-#endif