553 lines
19 KiB
C
553 lines
19 KiB
C
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#ifndef Py_CPYTHON_OBJECT_H
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# error "this header file must not be included directly"
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#endif
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PyAPI_FUNC(void) _Py_NewReference(PyObject *op);
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#ifdef Py_TRACE_REFS
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/* Py_TRACE_REFS is such major surgery that we call external routines. */
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PyAPI_FUNC(void) _Py_ForgetReference(PyObject *);
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#endif
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#ifdef Py_REF_DEBUG
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PyAPI_FUNC(Py_ssize_t) _Py_GetRefTotal(void);
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#endif
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/********************* String Literals ****************************************/
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/* This structure helps managing static strings. The basic usage goes like this:
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Instead of doing
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r = PyObject_CallMethod(o, "foo", "args", ...);
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do
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_Py_IDENTIFIER(foo);
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...
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r = _PyObject_CallMethodId(o, &PyId_foo, "args", ...);
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PyId_foo is a static variable, either on block level or file level. On first
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usage, the string "foo" is interned, and the structures are linked. On interpreter
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shutdown, all strings are released.
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Alternatively, _Py_static_string allows choosing the variable name.
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_PyUnicode_FromId returns a borrowed reference to the interned string.
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_PyObject_{Get,Set,Has}AttrId are __getattr__ versions using _Py_Identifier*.
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*/
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typedef struct _Py_Identifier {
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const char* string;
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// Index in PyInterpreterState.unicode.ids.array. It is process-wide
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// unique and must be initialized to -1.
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Py_ssize_t index;
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} _Py_Identifier;
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#define _Py_static_string_init(value) { .string = value, .index = -1 }
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#define _Py_static_string(varname, value) static _Py_Identifier varname = _Py_static_string_init(value)
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#define _Py_IDENTIFIER(varname) _Py_static_string(PyId_##varname, #varname)
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/* buffer interface */
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typedef struct bufferinfo {
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void *buf;
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PyObject *obj; /* owned reference */
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Py_ssize_t len;
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Py_ssize_t itemsize; /* This is Py_ssize_t so it can be
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pointed to by strides in simple case.*/
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int readonly;
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int ndim;
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char *format;
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Py_ssize_t *shape;
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Py_ssize_t *strides;
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Py_ssize_t *suboffsets;
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void *internal;
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} Py_buffer;
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typedef int (*getbufferproc)(PyObject *, Py_buffer *, int);
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typedef void (*releasebufferproc)(PyObject *, Py_buffer *);
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typedef PyObject *(*vectorcallfunc)(PyObject *callable, PyObject *const *args,
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size_t nargsf, PyObject *kwnames);
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/* Maximum number of dimensions */
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#define PyBUF_MAX_NDIM 64
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/* Flags for getting buffers */
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#define PyBUF_SIMPLE 0
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#define PyBUF_WRITABLE 0x0001
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/* we used to include an E, backwards compatible alias */
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#define PyBUF_WRITEABLE PyBUF_WRITABLE
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#define PyBUF_FORMAT 0x0004
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#define PyBUF_ND 0x0008
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#define PyBUF_STRIDES (0x0010 | PyBUF_ND)
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#define PyBUF_C_CONTIGUOUS (0x0020 | PyBUF_STRIDES)
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#define PyBUF_F_CONTIGUOUS (0x0040 | PyBUF_STRIDES)
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#define PyBUF_ANY_CONTIGUOUS (0x0080 | PyBUF_STRIDES)
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#define PyBUF_INDIRECT (0x0100 | PyBUF_STRIDES)
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#define PyBUF_CONTIG (PyBUF_ND | PyBUF_WRITABLE)
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#define PyBUF_CONTIG_RO (PyBUF_ND)
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#define PyBUF_STRIDED (PyBUF_STRIDES | PyBUF_WRITABLE)
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#define PyBUF_STRIDED_RO (PyBUF_STRIDES)
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#define PyBUF_RECORDS (PyBUF_STRIDES | PyBUF_WRITABLE | PyBUF_FORMAT)
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#define PyBUF_RECORDS_RO (PyBUF_STRIDES | PyBUF_FORMAT)
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#define PyBUF_FULL (PyBUF_INDIRECT | PyBUF_WRITABLE | PyBUF_FORMAT)
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#define PyBUF_FULL_RO (PyBUF_INDIRECT | PyBUF_FORMAT)
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#define PyBUF_READ 0x100
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#define PyBUF_WRITE 0x200
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/* End buffer interface */
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typedef struct {
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/* Number implementations must check *both*
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arguments for proper type and implement the necessary conversions
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in the slot functions themselves. */
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binaryfunc nb_add;
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binaryfunc nb_subtract;
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binaryfunc nb_multiply;
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binaryfunc nb_remainder;
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binaryfunc nb_divmod;
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ternaryfunc nb_power;
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unaryfunc nb_negative;
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unaryfunc nb_positive;
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unaryfunc nb_absolute;
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inquiry nb_bool;
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unaryfunc nb_invert;
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binaryfunc nb_lshift;
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binaryfunc nb_rshift;
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binaryfunc nb_and;
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binaryfunc nb_xor;
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binaryfunc nb_or;
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unaryfunc nb_int;
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void *nb_reserved; /* the slot formerly known as nb_long */
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unaryfunc nb_float;
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binaryfunc nb_inplace_add;
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binaryfunc nb_inplace_subtract;
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binaryfunc nb_inplace_multiply;
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binaryfunc nb_inplace_remainder;
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ternaryfunc nb_inplace_power;
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binaryfunc nb_inplace_lshift;
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binaryfunc nb_inplace_rshift;
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binaryfunc nb_inplace_and;
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binaryfunc nb_inplace_xor;
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binaryfunc nb_inplace_or;
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binaryfunc nb_floor_divide;
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binaryfunc nb_true_divide;
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binaryfunc nb_inplace_floor_divide;
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binaryfunc nb_inplace_true_divide;
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unaryfunc nb_index;
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binaryfunc nb_matrix_multiply;
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binaryfunc nb_inplace_matrix_multiply;
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} PyNumberMethods;
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typedef struct {
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lenfunc sq_length;
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binaryfunc sq_concat;
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ssizeargfunc sq_repeat;
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ssizeargfunc sq_item;
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void *was_sq_slice;
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ssizeobjargproc sq_ass_item;
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void *was_sq_ass_slice;
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objobjproc sq_contains;
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binaryfunc sq_inplace_concat;
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ssizeargfunc sq_inplace_repeat;
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} PySequenceMethods;
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typedef struct {
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lenfunc mp_length;
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binaryfunc mp_subscript;
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objobjargproc mp_ass_subscript;
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} PyMappingMethods;
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typedef PySendResult (*sendfunc)(PyObject *iter, PyObject *value, PyObject **result);
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typedef struct {
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unaryfunc am_await;
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unaryfunc am_aiter;
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unaryfunc am_anext;
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sendfunc am_send;
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} PyAsyncMethods;
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typedef struct {
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getbufferproc bf_getbuffer;
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releasebufferproc bf_releasebuffer;
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} PyBufferProcs;
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/* Allow printfunc in the tp_vectorcall_offset slot for
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* backwards-compatibility */
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typedef Py_ssize_t printfunc;
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// If this structure is modified, Doc/includes/typestruct.h should be updated
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// as well.
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struct _typeobject {
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PyObject_VAR_HEAD
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const char *tp_name; /* For printing, in format "<module>.<name>" */
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Py_ssize_t tp_basicsize, tp_itemsize; /* For allocation */
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/* Methods to implement standard operations */
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destructor tp_dealloc;
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Py_ssize_t tp_vectorcall_offset;
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getattrfunc tp_getattr;
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setattrfunc tp_setattr;
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PyAsyncMethods *tp_as_async; /* formerly known as tp_compare (Python 2)
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or tp_reserved (Python 3) */
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reprfunc tp_repr;
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/* Method suites for standard classes */
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PyNumberMethods *tp_as_number;
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PySequenceMethods *tp_as_sequence;
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PyMappingMethods *tp_as_mapping;
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/* More standard operations (here for binary compatibility) */
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hashfunc tp_hash;
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ternaryfunc tp_call;
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reprfunc tp_str;
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getattrofunc tp_getattro;
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setattrofunc tp_setattro;
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/* Functions to access object as input/output buffer */
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PyBufferProcs *tp_as_buffer;
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/* Flags to define presence of optional/expanded features */
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unsigned long tp_flags;
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const char *tp_doc; /* Documentation string */
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/* Assigned meaning in release 2.0 */
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/* call function for all accessible objects */
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traverseproc tp_traverse;
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/* delete references to contained objects */
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inquiry tp_clear;
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/* Assigned meaning in release 2.1 */
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/* rich comparisons */
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richcmpfunc tp_richcompare;
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/* weak reference enabler */
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Py_ssize_t tp_weaklistoffset;
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/* Iterators */
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getiterfunc tp_iter;
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iternextfunc tp_iternext;
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/* Attribute descriptor and subclassing stuff */
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struct PyMethodDef *tp_methods;
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struct PyMemberDef *tp_members;
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struct PyGetSetDef *tp_getset;
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// Strong reference on a heap type, borrowed reference on a static type
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struct _typeobject *tp_base;
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PyObject *tp_dict;
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descrgetfunc tp_descr_get;
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descrsetfunc tp_descr_set;
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Py_ssize_t tp_dictoffset;
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initproc tp_init;
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allocfunc tp_alloc;
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newfunc tp_new;
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freefunc tp_free; /* Low-level free-memory routine */
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inquiry tp_is_gc; /* For PyObject_IS_GC */
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PyObject *tp_bases;
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PyObject *tp_mro; /* method resolution order */
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PyObject *tp_cache;
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PyObject *tp_subclasses;
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PyObject *tp_weaklist;
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destructor tp_del;
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/* Type attribute cache version tag. Added in version 2.6 */
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unsigned int tp_version_tag;
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destructor tp_finalize;
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vectorcallfunc tp_vectorcall;
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};
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/* The *real* layout of a type object when allocated on the heap */
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typedef struct _heaptypeobject {
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/* Note: there's a dependency on the order of these members
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in slotptr() in typeobject.c . */
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PyTypeObject ht_type;
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PyAsyncMethods as_async;
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PyNumberMethods as_number;
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PyMappingMethods as_mapping;
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PySequenceMethods as_sequence; /* as_sequence comes after as_mapping,
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so that the mapping wins when both
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the mapping and the sequence define
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a given operator (e.g. __getitem__).
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see add_operators() in typeobject.c . */
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PyBufferProcs as_buffer;
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PyObject *ht_name, *ht_slots, *ht_qualname;
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struct _dictkeysobject *ht_cached_keys;
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PyObject *ht_module;
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/* here are optional user slots, followed by the members. */
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} PyHeapTypeObject;
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/* access macro to the members which are floating "behind" the object */
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#define PyHeapType_GET_MEMBERS(etype) \
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((PyMemberDef *)(((char *)etype) + Py_TYPE(etype)->tp_basicsize))
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PyAPI_FUNC(const char *) _PyType_Name(PyTypeObject *);
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PyAPI_FUNC(PyObject *) _PyType_Lookup(PyTypeObject *, PyObject *);
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PyAPI_FUNC(PyObject *) _PyType_LookupId(PyTypeObject *, _Py_Identifier *);
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PyAPI_FUNC(PyObject *) _PyObject_LookupSpecial(PyObject *, _Py_Identifier *);
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PyAPI_FUNC(PyTypeObject *) _PyType_CalculateMetaclass(PyTypeObject *, PyObject *);
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PyAPI_FUNC(PyObject *) _PyType_GetDocFromInternalDoc(const char *, const char *);
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PyAPI_FUNC(PyObject *) _PyType_GetTextSignatureFromInternalDoc(const char *, const char *);
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struct PyModuleDef;
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PyAPI_FUNC(PyObject *) _PyType_GetModuleByDef(PyTypeObject *, struct PyModuleDef *);
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struct _Py_Identifier;
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PyAPI_FUNC(int) PyObject_Print(PyObject *, FILE *, int);
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PyAPI_FUNC(void) _Py_BreakPoint(void);
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PyAPI_FUNC(void) _PyObject_Dump(PyObject *);
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PyAPI_FUNC(int) _PyObject_IsFreed(PyObject *);
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PyAPI_FUNC(int) _PyObject_IsAbstract(PyObject *);
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PyAPI_FUNC(PyObject *) _PyObject_GetAttrId(PyObject *, struct _Py_Identifier *);
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PyAPI_FUNC(int) _PyObject_SetAttrId(PyObject *, struct _Py_Identifier *, PyObject *);
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/* Replacements of PyObject_GetAttr() and _PyObject_GetAttrId() which
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don't raise AttributeError.
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Return 1 and set *result != NULL if an attribute is found.
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Return 0 and set *result == NULL if an attribute is not found;
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an AttributeError is silenced.
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Return -1 and set *result == NULL if an error other than AttributeError
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is raised.
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*/
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PyAPI_FUNC(int) _PyObject_LookupAttr(PyObject *, PyObject *, PyObject **);
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PyAPI_FUNC(int) _PyObject_LookupAttrId(PyObject *, struct _Py_Identifier *, PyObject **);
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PyAPI_FUNC(int) _PyObject_GetMethod(PyObject *obj, PyObject *name, PyObject **method);
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PyAPI_FUNC(PyObject **) _PyObject_GetDictPtr(PyObject *);
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PyAPI_FUNC(PyObject *) _PyObject_NextNotImplemented(PyObject *);
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PyAPI_FUNC(void) PyObject_CallFinalizer(PyObject *);
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PyAPI_FUNC(int) PyObject_CallFinalizerFromDealloc(PyObject *);
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/* Same as PyObject_Generic{Get,Set}Attr, but passing the attributes
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dict as the last parameter. */
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PyAPI_FUNC(PyObject *)
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_PyObject_GenericGetAttrWithDict(PyObject *, PyObject *, PyObject *, int);
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PyAPI_FUNC(int)
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_PyObject_GenericSetAttrWithDict(PyObject *, PyObject *,
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PyObject *, PyObject *);
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PyAPI_FUNC(PyObject *) _PyObject_FunctionStr(PyObject *);
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/* Safely decref `op` and set `op` to `op2`.
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*
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* As in case of Py_CLEAR "the obvious" code can be deadly:
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*
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* Py_DECREF(op);
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* op = op2;
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*
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* The safe way is:
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*
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* Py_SETREF(op, op2);
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*
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* That arranges to set `op` to `op2` _before_ decref'ing, so that any code
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* triggered as a side-effect of `op` getting torn down no longer believes
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* `op` points to a valid object.
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*
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* Py_XSETREF is a variant of Py_SETREF that uses Py_XDECREF instead of
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* Py_DECREF.
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*/
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#define Py_SETREF(op, op2) \
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do { \
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PyObject *_py_tmp = _PyObject_CAST(op); \
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(op) = (op2); \
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Py_DECREF(_py_tmp); \
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} while (0)
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#define Py_XSETREF(op, op2) \
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do { \
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PyObject *_py_tmp = _PyObject_CAST(op); \
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(op) = (op2); \
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Py_XDECREF(_py_tmp); \
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} while (0)
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PyAPI_DATA(PyTypeObject) _PyNone_Type;
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PyAPI_DATA(PyTypeObject) _PyNotImplemented_Type;
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/* Maps Py_LT to Py_GT, ..., Py_GE to Py_LE.
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* Defined in object.c.
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*/
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PyAPI_DATA(int) _Py_SwappedOp[];
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PyAPI_FUNC(void)
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_PyDebugAllocatorStats(FILE *out, const char *block_name, int num_blocks,
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size_t sizeof_block);
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PyAPI_FUNC(void)
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_PyObject_DebugTypeStats(FILE *out);
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/* Define a pair of assertion macros:
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_PyObject_ASSERT_FROM(), _PyObject_ASSERT_WITH_MSG() and _PyObject_ASSERT().
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These work like the regular C assert(), in that they will abort the
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process with a message on stderr if the given condition fails to hold,
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but compile away to nothing if NDEBUG is defined.
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However, before aborting, Python will also try to call _PyObject_Dump() on
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the given object. This may be of use when investigating bugs in which a
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particular object is corrupt (e.g. buggy a tp_visit method in an extension
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module breaking the garbage collector), to help locate the broken objects.
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The WITH_MSG variant allows you to supply an additional message that Python
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will attempt to print to stderr, after the object dump. */
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#ifdef NDEBUG
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|
/* No debugging: compile away the assertions: */
|
||
|
# define _PyObject_ASSERT_FROM(obj, expr, msg, filename, lineno, func) \
|
||
|
((void)0)
|
||
|
#else
|
||
|
/* With debugging: generate checks: */
|
||
|
# define _PyObject_ASSERT_FROM(obj, expr, msg, filename, lineno, func) \
|
||
|
((expr) \
|
||
|
? (void)(0) \
|
||
|
: _PyObject_AssertFailed((obj), Py_STRINGIFY(expr), \
|
||
|
(msg), (filename), (lineno), (func)))
|
||
|
#endif
|
||
|
|
||
|
#define _PyObject_ASSERT_WITH_MSG(obj, expr, msg) \
|
||
|
_PyObject_ASSERT_FROM(obj, expr, msg, __FILE__, __LINE__, __func__)
|
||
|
#define _PyObject_ASSERT(obj, expr) \
|
||
|
_PyObject_ASSERT_WITH_MSG(obj, expr, NULL)
|
||
|
|
||
|
#define _PyObject_ASSERT_FAILED_MSG(obj, msg) \
|
||
|
_PyObject_AssertFailed((obj), NULL, (msg), __FILE__, __LINE__, __func__)
|
||
|
|
||
|
/* Declare and define _PyObject_AssertFailed() even when NDEBUG is defined,
|
||
|
to avoid causing compiler/linker errors when building extensions without
|
||
|
NDEBUG against a Python built with NDEBUG defined.
|
||
|
|
||
|
msg, expr and function can be NULL. */
|
||
|
PyAPI_FUNC(void) _Py_NO_RETURN _PyObject_AssertFailed(
|
||
|
PyObject *obj,
|
||
|
const char *expr,
|
||
|
const char *msg,
|
||
|
const char *file,
|
||
|
int line,
|
||
|
const char *function);
|
||
|
|
||
|
/* Check if an object is consistent. For example, ensure that the reference
|
||
|
counter is greater than or equal to 1, and ensure that ob_type is not NULL.
|
||
|
|
||
|
Call _PyObject_AssertFailed() if the object is inconsistent.
|
||
|
|
||
|
If check_content is zero, only check header fields: reduce the overhead.
|
||
|
|
||
|
The function always return 1. The return value is just here to be able to
|
||
|
write:
|
||
|
|
||
|
assert(_PyObject_CheckConsistency(obj, 1)); */
|
||
|
PyAPI_FUNC(int) _PyObject_CheckConsistency(
|
||
|
PyObject *op,
|
||
|
int check_content);
|
||
|
|
||
|
|
||
|
/* Trashcan mechanism, thanks to Christian Tismer.
|
||
|
|
||
|
When deallocating a container object, it's possible to trigger an unbounded
|
||
|
chain of deallocations, as each Py_DECREF in turn drops the refcount on "the
|
||
|
next" object in the chain to 0. This can easily lead to stack overflows,
|
||
|
especially in threads (which typically have less stack space to work with).
|
||
|
|
||
|
A container object can avoid this by bracketing the body of its tp_dealloc
|
||
|
function with a pair of macros:
|
||
|
|
||
|
static void
|
||
|
mytype_dealloc(mytype *p)
|
||
|
{
|
||
|
... declarations go here ...
|
||
|
|
||
|
PyObject_GC_UnTrack(p); // must untrack first
|
||
|
Py_TRASHCAN_BEGIN(p, mytype_dealloc)
|
||
|
... The body of the deallocator goes here, including all calls ...
|
||
|
... to Py_DECREF on contained objects. ...
|
||
|
Py_TRASHCAN_END // there should be no code after this
|
||
|
}
|
||
|
|
||
|
CAUTION: Never return from the middle of the body! If the body needs to
|
||
|
"get out early", put a label immediately before the Py_TRASHCAN_END
|
||
|
call, and goto it. Else the call-depth counter (see below) will stay
|
||
|
above 0 forever, and the trashcan will never get emptied.
|
||
|
|
||
|
How it works: The BEGIN macro increments a call-depth counter. So long
|
||
|
as this counter is small, the body of the deallocator is run directly without
|
||
|
further ado. But if the counter gets large, it instead adds p to a list of
|
||
|
objects to be deallocated later, skips the body of the deallocator, and
|
||
|
resumes execution after the END macro. The tp_dealloc routine then returns
|
||
|
without deallocating anything (and so unbounded call-stack depth is avoided).
|
||
|
|
||
|
When the call stack finishes unwinding again, code generated by the END macro
|
||
|
notices this, and calls another routine to deallocate all the objects that
|
||
|
may have been added to the list of deferred deallocations. In effect, a
|
||
|
chain of N deallocations is broken into (N-1)/(PyTrash_UNWIND_LEVEL-1) pieces,
|
||
|
with the call stack never exceeding a depth of PyTrash_UNWIND_LEVEL.
|
||
|
|
||
|
Since the tp_dealloc of a subclass typically calls the tp_dealloc of the base
|
||
|
class, we need to ensure that the trashcan is only triggered on the tp_dealloc
|
||
|
of the actual class being deallocated. Otherwise we might end up with a
|
||
|
partially-deallocated object. To check this, the tp_dealloc function must be
|
||
|
passed as second argument to Py_TRASHCAN_BEGIN().
|
||
|
*/
|
||
|
|
||
|
/* This is the old private API, invoked by the macros before 3.2.4.
|
||
|
Kept for binary compatibility of extensions using the stable ABI. */
|
||
|
PyAPI_FUNC(void) _PyTrash_deposit_object(PyObject*);
|
||
|
PyAPI_FUNC(void) _PyTrash_destroy_chain(void);
|
||
|
|
||
|
/* This is the old private API, invoked by the macros before 3.9.
|
||
|
Kept for binary compatibility of extensions using the stable ABI. */
|
||
|
PyAPI_FUNC(void) _PyTrash_thread_deposit_object(PyObject*);
|
||
|
PyAPI_FUNC(void) _PyTrash_thread_destroy_chain(void);
|
||
|
|
||
|
/* Forward declarations for PyThreadState */
|
||
|
struct _ts;
|
||
|
|
||
|
/* Python 3.9 private API, invoked by the macros below. */
|
||
|
PyAPI_FUNC(int) _PyTrash_begin(struct _ts *tstate, PyObject *op);
|
||
|
PyAPI_FUNC(void) _PyTrash_end(struct _ts *tstate);
|
||
|
/* Python 3.10 private API, invoked by the Py_TRASHCAN_BEGIN(). */
|
||
|
PyAPI_FUNC(int) _PyTrash_cond(PyObject *op, destructor dealloc);
|
||
|
|
||
|
#define PyTrash_UNWIND_LEVEL 50
|
||
|
|
||
|
#define Py_TRASHCAN_BEGIN_CONDITION(op, cond) \
|
||
|
do { \
|
||
|
PyThreadState *_tstate = NULL; \
|
||
|
/* If "cond" is false, then _tstate remains NULL and the deallocator \
|
||
|
* is run normally without involving the trashcan */ \
|
||
|
if (cond) { \
|
||
|
_tstate = PyThreadState_Get(); \
|
||
|
if (_PyTrash_begin(_tstate, _PyObject_CAST(op))) { \
|
||
|
break; \
|
||
|
} \
|
||
|
}
|
||
|
/* The body of the deallocator is here. */
|
||
|
#define Py_TRASHCAN_END \
|
||
|
if (_tstate) { \
|
||
|
_PyTrash_end(_tstate); \
|
||
|
} \
|
||
|
} while (0);
|
||
|
|
||
|
#define Py_TRASHCAN_BEGIN(op, dealloc) \
|
||
|
Py_TRASHCAN_BEGIN_CONDITION(op, \
|
||
|
_PyTrash_cond(_PyObject_CAST(op), (destructor)dealloc))
|
||
|
|
||
|
/* For backwards compatibility, these macros enable the trashcan
|
||
|
* unconditionally */
|
||
|
#define Py_TRASHCAN_SAFE_BEGIN(op) Py_TRASHCAN_BEGIN_CONDITION(op, 1)
|
||
|
#define Py_TRASHCAN_SAFE_END(op) Py_TRASHCAN_END
|