rewrite for style, clarify, and comments
[python.git] / Include / longobject.h
blobea9e38767cbce1dce2f95cd6ec09383a1d443f1c
1 #ifndef Py_LONGOBJECT_H
2 #define Py_LONGOBJECT_H
3 #ifdef __cplusplus
4 extern "C" {
5 #endif
8 /* Long (arbitrary precision) integer object interface */
10 typedef struct _longobject PyLongObject; /* Revealed in longintrepr.h */
12 PyAPI_DATA(PyTypeObject) PyLong_Type;
14 #define PyLong_Check(op) \
15 PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_LONG_SUBCLASS)
16 #define PyLong_CheckExact(op) (Py_TYPE(op) == &PyLong_Type)
18 PyAPI_FUNC(PyObject *) PyLong_FromLong(long);
19 PyAPI_FUNC(PyObject *) PyLong_FromUnsignedLong(unsigned long);
20 PyAPI_FUNC(PyObject *) PyLong_FromDouble(double);
21 PyAPI_FUNC(PyObject *) PyLong_FromSize_t(size_t);
22 PyAPI_FUNC(PyObject *) PyLong_FromSsize_t(Py_ssize_t);
23 PyAPI_FUNC(long) PyLong_AsLong(PyObject *);
24 PyAPI_FUNC(unsigned long) PyLong_AsUnsignedLong(PyObject *);
25 PyAPI_FUNC(unsigned long) PyLong_AsUnsignedLongMask(PyObject *);
26 PyAPI_FUNC(Py_ssize_t) PyLong_AsSsize_t(PyObject *);
27 PyAPI_FUNC(PyObject *) PyLong_GetInfo(void);
29 /* For use by intobject.c only */
30 #define _PyLong_AsSsize_t PyLong_AsSsize_t
31 #define _PyLong_FromSize_t PyLong_FromSize_t
32 #define _PyLong_FromSsize_t PyLong_FromSsize_t
33 PyAPI_DATA(int) _PyLong_DigitValue[256];
35 /* _PyLong_AsScaledDouble returns a double x and an exponent e such that
36 the true value is approximately equal to x * 2**(SHIFT*e). e is >= 0.
37 x is 0.0 if and only if the input is 0 (in which case, e and x are both
38 zeroes). Overflow is impossible. Note that the exponent returned must
39 be multiplied by SHIFT! There may not be enough room in an int to store
40 e*SHIFT directly. */
41 PyAPI_FUNC(double) _PyLong_AsScaledDouble(PyObject *vv, int *e);
43 PyAPI_FUNC(double) PyLong_AsDouble(PyObject *);
44 PyAPI_FUNC(PyObject *) PyLong_FromVoidPtr(void *);
45 PyAPI_FUNC(void *) PyLong_AsVoidPtr(PyObject *);
47 #ifdef HAVE_LONG_LONG
48 PyAPI_FUNC(PyObject *) PyLong_FromLongLong(PY_LONG_LONG);
49 PyAPI_FUNC(PyObject *) PyLong_FromUnsignedLongLong(unsigned PY_LONG_LONG);
50 PyAPI_FUNC(PY_LONG_LONG) PyLong_AsLongLong(PyObject *);
51 PyAPI_FUNC(unsigned PY_LONG_LONG) PyLong_AsUnsignedLongLong(PyObject *);
52 PyAPI_FUNC(unsigned PY_LONG_LONG) PyLong_AsUnsignedLongLongMask(PyObject *);
53 #endif /* HAVE_LONG_LONG */
55 PyAPI_FUNC(PyObject *) PyLong_FromString(char *, char **, int);
56 #ifdef Py_USING_UNICODE
57 PyAPI_FUNC(PyObject *) PyLong_FromUnicode(Py_UNICODE*, Py_ssize_t, int);
58 #endif
60 /* _PyLong_Sign. Return 0 if v is 0, -1 if v < 0, +1 if v > 0.
61 v must not be NULL, and must be a normalized long.
62 There are no error cases.
64 PyAPI_FUNC(int) _PyLong_Sign(PyObject *v);
67 /* _PyLong_NumBits. Return the number of bits needed to represent the
68 absolute value of a long. For example, this returns 1 for 1 and -1, 2
69 for 2 and -2, and 2 for 3 and -3. It returns 0 for 0.
70 v must not be NULL, and must be a normalized long.
71 (size_t)-1 is returned and OverflowError set if the true result doesn't
72 fit in a size_t.
74 PyAPI_FUNC(size_t) _PyLong_NumBits(PyObject *v);
76 /* _PyLong_FromByteArray: View the n unsigned bytes as a binary integer in
77 base 256, and return a Python long with the same numeric value.
78 If n is 0, the integer is 0. Else:
79 If little_endian is 1/true, bytes[n-1] is the MSB and bytes[0] the LSB;
80 else (little_endian is 0/false) bytes[0] is the MSB and bytes[n-1] the
81 LSB.
82 If is_signed is 0/false, view the bytes as a non-negative integer.
83 If is_signed is 1/true, view the bytes as a 2's-complement integer,
84 non-negative if bit 0x80 of the MSB is clear, negative if set.
85 Error returns:
86 + Return NULL with the appropriate exception set if there's not
87 enough memory to create the Python long.
89 PyAPI_FUNC(PyObject *) _PyLong_FromByteArray(
90 const unsigned char* bytes, size_t n,
91 int little_endian, int is_signed);
93 /* _PyLong_AsByteArray: Convert the least-significant 8*n bits of long
94 v to a base-256 integer, stored in array bytes. Normally return 0,
95 return -1 on error.
96 If little_endian is 1/true, store the MSB at bytes[n-1] and the LSB at
97 bytes[0]; else (little_endian is 0/false) store the MSB at bytes[0] and
98 the LSB at bytes[n-1].
99 If is_signed is 0/false, it's an error if v < 0; else (v >= 0) n bytes
100 are filled and there's nothing special about bit 0x80 of the MSB.
101 If is_signed is 1/true, bytes is filled with the 2's-complement
102 representation of v's value. Bit 0x80 of the MSB is the sign bit.
103 Error returns (-1):
104 + is_signed is 0 and v < 0. TypeError is set in this case, and bytes
105 isn't altered.
106 + n isn't big enough to hold the full mathematical value of v. For
107 example, if is_signed is 0 and there are more digits in the v than
108 fit in n; or if is_signed is 1, v < 0, and n is just 1 bit shy of
109 being large enough to hold a sign bit. OverflowError is set in this
110 case, but bytes holds the least-signficant n bytes of the true value.
112 PyAPI_FUNC(int) _PyLong_AsByteArray(PyLongObject* v,
113 unsigned char* bytes, size_t n,
114 int little_endian, int is_signed);
116 /* _PyLong_Format: Convert the long to a string object with given base,
117 appending a base prefix of 0[box] if base is 2, 8 or 16.
118 Add a trailing "L" if addL is non-zero.
119 If newstyle is zero, then use the pre-2.6 behavior of octal having
120 a leading "0", instead of the prefix "0o" */
121 PyAPI_FUNC(PyObject *) _PyLong_Format(PyObject *aa, int base, int addL, int newstyle);
123 /* Format the object based on the format_spec, as defined in PEP 3101
124 (Advanced String Formatting). */
125 PyAPI_FUNC(PyObject *) _PyLong_FormatAdvanced(PyObject *obj,
126 char *format_spec,
127 Py_ssize_t format_spec_len);
129 #ifdef __cplusplus
131 #endif
132 #endif /* !Py_LONGOBJECT_H */