Critics have remarked that those four worthies were truly peerless throughout the ages; yet the present falls short of the pastβthe ancients favored unadorned simplicity, whereas the moderns prefer refined elegance. Styles of substance and ornament rise and fall in succession, shifting with the changing mores of the times; such evolution is simply the natural order of things. The ideal lies in honoring antiquity without clashing with the present, and embracing modernity without succumbing to its flawsβembodying that perfect balance of substance and refinement that defines the true gentleman. There is surely no need to abandon a carved palace in favor of a cave dwelling, or to trade a jade carriage for a primitive cart with solid wooden wheels.
Current path: usr/include/python2.7/
β Cloned to:
β¬οΈ Go up: /usr/include
#ifndef Py_LONGINTREPR_H
#define Py_LONGINTREPR_H
#ifdef __cplusplus
extern "C" {
#endif
/* This is published for the benefit of "friend" marshal.c only. */
/* Parameters of the long integer representation. There are two different
sets of parameters: one set for 30-bit digits, stored in an unsigned 32-bit
integer type, and one set for 15-bit digits with each digit stored in an
unsigned short. The value of PYLONG_BITS_IN_DIGIT, defined either at
configure time or in pyport.h, is used to decide which digit size to use.
Type 'digit' should be able to hold 2*PyLong_BASE-1, and type 'twodigits'
should be an unsigned integer type able to hold all integers up to
PyLong_BASE*PyLong_BASE-1. x_sub assumes that 'digit' is an unsigned type,
and that overflow is handled by taking the result modulo 2**N for some N >
PyLong_SHIFT. The majority of the code doesn't care about the precise
value of PyLong_SHIFT, but there are some notable exceptions:
- long_pow() requires that PyLong_SHIFT be divisible by 5
- PyLong_{As,From}ByteArray require that PyLong_SHIFT be at least 8
- long_hash() requires that PyLong_SHIFT is *strictly* less than the number
of bits in an unsigned long, as do the PyLong <-> long (or unsigned long)
conversion functions
- the long <-> size_t/Py_ssize_t conversion functions expect that
PyLong_SHIFT is strictly less than the number of bits in a size_t
- the marshal code currently expects that PyLong_SHIFT is a multiple of 15
The values 15 and 30 should fit all of the above requirements, on any
platform.
*/
#if PYLONG_BITS_IN_DIGIT == 30
#if !(defined HAVE_UINT64_T && defined HAVE_UINT32_T && \
defined HAVE_INT64_T && defined HAVE_INT32_T)
#error "30-bit long digits requested, but the necessary types are not available on this platform"
#endif
typedef PY_UINT32_T digit;
typedef PY_INT32_T sdigit; /* signed variant of digit */
typedef PY_UINT64_T twodigits;
typedef PY_INT64_T stwodigits; /* signed variant of twodigits */
#define PyLong_SHIFT 30
#define _PyLong_DECIMAL_SHIFT 9 /* max(e such that 10**e fits in a digit) */
#define _PyLong_DECIMAL_BASE ((digit)1000000000) /* 10 ** DECIMAL_SHIFT */
#elif PYLONG_BITS_IN_DIGIT == 15
typedef unsigned short digit;
typedef short sdigit; /* signed variant of digit */
typedef unsigned long twodigits;
typedef long stwodigits; /* signed variant of twodigits */
#define PyLong_SHIFT 15
#define _PyLong_DECIMAL_SHIFT 4 /* max(e such that 10**e fits in a digit) */
#define _PyLong_DECIMAL_BASE ((digit)10000) /* 10 ** DECIMAL_SHIFT */
#else
#error "PYLONG_BITS_IN_DIGIT should be 15 or 30"
#endif
#define PyLong_BASE ((digit)1 << PyLong_SHIFT)
#define PyLong_MASK ((digit)(PyLong_BASE - 1))
/* b/w compatibility with Python 2.5 */
#define SHIFT PyLong_SHIFT
#define BASE PyLong_BASE
#define MASK PyLong_MASK
#if PyLong_SHIFT % 5 != 0
#error "longobject.c requires that PyLong_SHIFT be divisible by 5"
#endif
/* Long integer representation.
The absolute value of a number is equal to
SUM(for i=0 through abs(ob_size)-1) ob_digit[i] * 2**(SHIFT*i)
Negative numbers are represented with ob_size < 0;
zero is represented by ob_size == 0.
In a normalized number, ob_digit[abs(ob_size)-1] (the most significant
digit) is never zero. Also, in all cases, for all valid i,
0 <= ob_digit[i] <= MASK.
The allocation function takes care of allocating extra memory
so that ob_digit[0] ... ob_digit[abs(ob_size)-1] are actually available.
CAUTION: Generic code manipulating subtypes of PyVarObject has to
aware that longs abuse ob_size's sign bit.
*/
struct _longobject {
PyObject_VAR_HEAD
digit ob_digit[1];
};
PyAPI_FUNC(PyLongObject *) _PyLong_New(Py_ssize_t);
/* Return a copy of src. */
PyAPI_FUNC(PyObject *) _PyLong_Copy(PyLongObject *src);
#ifdef __cplusplus
}
#endif
#endif /* !Py_LONGINTREPR_H */