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898 lines
24 KiB
898 lines
24 KiB
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/* Buffer object implementation */
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#include "Python.h"
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typedef struct {
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PyObject_HEAD
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PyObject *b_base;
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void *b_ptr;
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Py_ssize_t b_size;
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Py_ssize_t b_offset;
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int b_readonly;
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long b_hash;
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} PyBufferObject;
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enum buffer_t {
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READ_BUFFER,
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WRITE_BUFFER,
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CHAR_BUFFER,
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ANY_BUFFER
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};
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static int
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get_buf(PyBufferObject *self, void **ptr, Py_ssize_t *size,
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enum buffer_t buffer_type)
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{
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if (self->b_base == NULL) {
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assert (ptr != NULL);
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*ptr = self->b_ptr;
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*size = self->b_size;
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}
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else {
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Py_ssize_t count, offset;
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readbufferproc proc = 0;
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PyBufferProcs *bp = Py_TYPE(self->b_base)->tp_as_buffer;
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if ((*bp->bf_getsegcount)(self->b_base, NULL) != 1) {
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PyErr_SetString(PyExc_TypeError,
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"single-segment buffer object expected");
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return 0;
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}
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if ((buffer_type == READ_BUFFER) ||
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((buffer_type == ANY_BUFFER) && self->b_readonly))
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proc = bp->bf_getreadbuffer;
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else if ((buffer_type == WRITE_BUFFER) ||
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(buffer_type == ANY_BUFFER))
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proc = (readbufferproc)bp->bf_getwritebuffer;
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else if (buffer_type == CHAR_BUFFER) {
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if (!PyType_HasFeature(Py_TYPE(self),
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Py_TPFLAGS_HAVE_GETCHARBUFFER)) {
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PyErr_SetString(PyExc_TypeError,
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"Py_TPFLAGS_HAVE_GETCHARBUFFER needed");
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return 0;
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}
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proc = (readbufferproc)bp->bf_getcharbuffer;
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}
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if (!proc) {
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char *buffer_type_name;
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switch (buffer_type) {
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case READ_BUFFER:
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buffer_type_name = "read";
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break;
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case WRITE_BUFFER:
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buffer_type_name = "write";
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break;
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case CHAR_BUFFER:
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buffer_type_name = "char";
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break;
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default:
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buffer_type_name = "no";
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break;
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}
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PyErr_Format(PyExc_TypeError,
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"%s buffer type not available",
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buffer_type_name);
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return 0;
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}
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if ((count = (*proc)(self->b_base, 0, ptr)) < 0)
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return 0;
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/* apply constraints to the start/end */
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if (self->b_offset > count)
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offset = count;
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else
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offset = self->b_offset;
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*(char **)ptr = *(char **)ptr + offset;
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if (self->b_size == Py_END_OF_BUFFER)
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*size = count;
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else
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*size = self->b_size;
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if (*size > count - offset)
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*size = count - offset;
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}
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return 1;
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}
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static PyObject *
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buffer_from_memory(PyObject *base, Py_ssize_t size, Py_ssize_t offset, void *ptr,
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int readonly)
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{
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PyBufferObject * b;
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if (size < 0 && size != Py_END_OF_BUFFER) {
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PyErr_SetString(PyExc_ValueError,
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"size must be zero or positive");
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return NULL;
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}
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if (offset < 0) {
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PyErr_SetString(PyExc_ValueError,
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"offset must be zero or positive");
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return NULL;
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}
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b = PyObject_NEW(PyBufferObject, &PyBuffer_Type);
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if ( b == NULL )
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return NULL;
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Py_XINCREF(base);
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b->b_base = base;
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b->b_ptr = ptr;
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b->b_size = size;
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b->b_offset = offset;
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b->b_readonly = readonly;
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b->b_hash = -1;
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return (PyObject *) b;
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}
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static PyObject *
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buffer_from_object(PyObject *base, Py_ssize_t size, Py_ssize_t offset, int readonly)
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{
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if (offset < 0) {
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PyErr_SetString(PyExc_ValueError,
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"offset must be zero or positive");
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return NULL;
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}
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if ( PyBuffer_Check(base) && (((PyBufferObject *)base)->b_base) ) {
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/* another buffer, refer to the base object */
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PyBufferObject *b = (PyBufferObject *)base;
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if (b->b_size != Py_END_OF_BUFFER) {
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Py_ssize_t base_size = b->b_size - offset;
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if (base_size < 0)
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base_size = 0;
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if (size == Py_END_OF_BUFFER || size > base_size)
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size = base_size;
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}
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offset += b->b_offset;
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base = b->b_base;
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}
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return buffer_from_memory(base, size, offset, NULL, readonly);
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}
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PyObject *
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PyBuffer_FromObject(PyObject *base, Py_ssize_t offset, Py_ssize_t size)
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{
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PyBufferProcs *pb = base->ob_type->tp_as_buffer;
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if ( pb == NULL ||
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pb->bf_getreadbuffer == NULL ||
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pb->bf_getsegcount == NULL )
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{
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PyErr_SetString(PyExc_TypeError, "buffer object expected");
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return NULL;
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}
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return buffer_from_object(base, size, offset, 1);
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}
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PyObject *
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PyBuffer_FromReadWriteObject(PyObject *base, Py_ssize_t offset, Py_ssize_t size)
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{
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PyBufferProcs *pb = base->ob_type->tp_as_buffer;
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if ( pb == NULL ||
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pb->bf_getwritebuffer == NULL ||
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pb->bf_getsegcount == NULL )
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{
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PyErr_SetString(PyExc_TypeError, "buffer object expected");
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return NULL;
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}
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return buffer_from_object(base, size, offset, 0);
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}
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PyObject *
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PyBuffer_FromMemory(void *ptr, Py_ssize_t size)
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{
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return buffer_from_memory(NULL, size, 0, ptr, 1);
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}
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PyObject *
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PyBuffer_FromReadWriteMemory(void *ptr, Py_ssize_t size)
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{
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return buffer_from_memory(NULL, size, 0, ptr, 0);
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}
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PyObject *
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PyBuffer_New(Py_ssize_t size)
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{
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PyObject *o;
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PyBufferObject * b;
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if (size < 0) {
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PyErr_SetString(PyExc_ValueError,
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"size must be zero or positive");
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return NULL;
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}
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if (sizeof(*b) > PY_SSIZE_T_MAX - size) {
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/* unlikely */
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return PyErr_NoMemory();
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}
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/* Inline PyObject_New */
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o = (PyObject *)PyObject_MALLOC(sizeof(*b) + size);
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if ( o == NULL )
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return PyErr_NoMemory();
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b = (PyBufferObject *) PyObject_INIT(o, &PyBuffer_Type);
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b->b_base = NULL;
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b->b_ptr = (void *)(b + 1);
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b->b_size = size;
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b->b_offset = 0;
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b->b_readonly = 0;
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b->b_hash = -1;
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return o;
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}
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/* Methods */
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static PyObject *
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buffer_new(PyTypeObject *type, PyObject *args, PyObject *kw)
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{
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PyObject *ob;
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Py_ssize_t offset = 0;
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Py_ssize_t size = Py_END_OF_BUFFER;
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if (PyErr_WarnPy3k("buffer() not supported in 3.x", 1) < 0)
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return NULL;
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if (!_PyArg_NoKeywords("buffer()", kw))
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return NULL;
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if (!PyArg_ParseTuple(args, "O|nn:buffer", &ob, &offset, &size))
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return NULL;
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return PyBuffer_FromObject(ob, offset, size);
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}
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PyDoc_STRVAR(buffer_doc,
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"buffer(object [, offset[, size]])\n\
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\n\
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Create a new buffer object which references the given object.\n\
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The buffer will reference a slice of the target object from the\n\
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start of the object (or at the specified offset). The slice will\n\
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extend to the end of the target object (or with the specified size).");
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static void
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buffer_dealloc(PyBufferObject *self)
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{
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Py_XDECREF(self->b_base);
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PyObject_DEL(self);
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}
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static int
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buffer_compare(PyBufferObject *self, PyBufferObject *other)
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{
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void *p1, *p2;
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Py_ssize_t len_self, len_other, min_len;
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int cmp;
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if (!get_buf(self, &p1, &len_self, ANY_BUFFER))
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return -1;
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if (!get_buf(other, &p2, &len_other, ANY_BUFFER))
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return -1;
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min_len = (len_self < len_other) ? len_self : len_other;
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if (min_len > 0) {
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cmp = memcmp(p1, p2, min_len);
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if (cmp != 0)
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return cmp < 0 ? -1 : 1;
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}
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return (len_self < len_other) ? -1 : (len_self > len_other) ? 1 : 0;
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}
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static PyObject *
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buffer_repr(PyBufferObject *self)
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{
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const char *status = self->b_readonly ? "read-only" : "read-write";
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if ( self->b_base == NULL )
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return PyString_FromFormat("<%s buffer ptr %p, size %zd at %p>",
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status,
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self->b_ptr,
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self->b_size,
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self);
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else
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return PyString_FromFormat(
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"<%s buffer for %p, size %zd, offset %zd at %p>",
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status,
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self->b_base,
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self->b_size,
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self->b_offset,
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self);
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}
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static long
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buffer_hash(PyBufferObject *self)
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{
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void *ptr;
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Py_ssize_t size;
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register Py_ssize_t len;
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register unsigned char *p;
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register long x;
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if ( self->b_hash != -1 )
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return self->b_hash;
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/* XXX potential bugs here, a readonly buffer does not imply that the
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* underlying memory is immutable. b_readonly is a necessary but not
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* sufficient condition for a buffer to be hashable. Perhaps it would
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* be better to only allow hashing if the underlying object is known to
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* be immutable (e.g. PyString_Check() is true). Another idea would
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* be to call tp_hash on the underlying object and see if it raises
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* an error. */
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if ( !self->b_readonly )
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{
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PyErr_SetString(PyExc_TypeError,
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"writable buffers are not hashable");
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return -1;
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}
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if (!get_buf(self, &ptr, &size, ANY_BUFFER))
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return -1;
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p = (unsigned char *) ptr;
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len = size;
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/*
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We make the hash of the empty buffer be 0, rather than using
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(prefix ^ suffix), since this slightly obfuscates the hash secret
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*/
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if (len == 0) {
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self->b_hash = 0;
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return 0;
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}
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x = _Py_HashSecret.prefix;
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x ^= *p << 7;
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while (--len >= 0)
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x = (1000003*x) ^ *p++;
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x ^= size;
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x ^= _Py_HashSecret.suffix;
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if (x == -1)
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x = -2;
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self->b_hash = x;
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return x;
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}
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static PyObject *
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buffer_str(PyBufferObject *self)
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{
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void *ptr;
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Py_ssize_t size;
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if (!get_buf(self, &ptr, &size, ANY_BUFFER))
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return NULL;
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return PyString_FromStringAndSize((const char *)ptr, size);
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}
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/* Sequence methods */
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static Py_ssize_t
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buffer_length(PyBufferObject *self)
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{
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void *ptr;
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Py_ssize_t size;
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if (!get_buf(self, &ptr, &size, ANY_BUFFER))
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return -1;
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return size;
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}
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static PyObject *
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buffer_concat(PyBufferObject *self, PyObject *other)
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{
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PyBufferProcs *pb = other->ob_type->tp_as_buffer;
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void *ptr1, *ptr2;
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char *p;
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PyObject *ob;
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Py_ssize_t size, count;
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if ( pb == NULL ||
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pb->bf_getreadbuffer == NULL ||
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pb->bf_getsegcount == NULL )
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{
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PyErr_BadArgument();
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return NULL;
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}
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if ( (*pb->bf_getsegcount)(other, NULL) != 1 )
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{
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/* ### use a different exception type/message? */
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PyErr_SetString(PyExc_TypeError,
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"single-segment buffer object expected");
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return NULL;
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}
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if (!get_buf(self, &ptr1, &size, ANY_BUFFER))
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return NULL;
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/* optimize special case */
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if ( size == 0 )
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{
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Py_INCREF(other);
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return other;
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}
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if ( (count = (*pb->bf_getreadbuffer)(other, 0, &ptr2)) < 0 )
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return NULL;
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assert(count <= PY_SIZE_MAX - size);
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ob = PyString_FromStringAndSize(NULL, size + count);
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if ( ob == NULL )
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return NULL;
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p = PyString_AS_STRING(ob);
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memcpy(p, ptr1, size);
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memcpy(p + size, ptr2, count);
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/* there is an extra byte in the string object, so this is safe */
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p[size + count] = '\0';
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return ob;
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}
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static PyObject *
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buffer_repeat(PyBufferObject *self, Py_ssize_t count)
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{
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PyObject *ob;
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register char *p;
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void *ptr;
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Py_ssize_t size;
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if ( count < 0 )
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count = 0;
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if (!get_buf(self, &ptr, &size, ANY_BUFFER))
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return NULL;
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if (count > PY_SSIZE_T_MAX / size) {
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PyErr_SetString(PyExc_MemoryError, "result too large");
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return NULL;
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}
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ob = PyString_FromStringAndSize(NULL, size * count);
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if ( ob == NULL )
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return NULL;
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p = PyString_AS_STRING(ob);
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while ( count-- )
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{
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memcpy(p, ptr, size);
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p += size;
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}
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/* there is an extra byte in the string object, so this is safe */
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*p = '\0';
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return ob;
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}
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static PyObject *
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buffer_item_impl(void *ptr, Py_ssize_t size, Py_ssize_t idx)
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{
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if ( idx < 0 || idx >= size ) {
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PyErr_SetString(PyExc_IndexError, "buffer index out of range");
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return NULL;
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}
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return PyString_FromStringAndSize((char *)ptr + idx, 1);
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}
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static PyObject *
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buffer_item(PyBufferObject *self, Py_ssize_t idx)
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{
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void *ptr;
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Py_ssize_t size;
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if (!get_buf(self, &ptr, &size, ANY_BUFFER))
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return NULL;
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return buffer_item_impl(ptr, size, idx);
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}
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static PyObject *
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buffer_slice(PyBufferObject *self, Py_ssize_t left, Py_ssize_t right)
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{
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void *ptr;
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Py_ssize_t size;
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if (!get_buf(self, &ptr, &size, ANY_BUFFER))
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return NULL;
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if ( left < 0 )
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left = 0;
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if ( right < 0 )
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right = 0;
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if ( right > size )
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right = size;
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if ( right < left )
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right = left;
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return PyString_FromStringAndSize((char *)ptr + left,
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right - left);
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}
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static PyObject *
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buffer_subscript(PyBufferObject *self, PyObject *item)
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{
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void *p;
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Py_ssize_t size;
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if (PyIndex_Check(item)) {
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Py_ssize_t i = PyNumber_AsSsize_t(item, PyExc_IndexError);
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if (i == -1 && PyErr_Occurred())
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return NULL;
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if (!get_buf(self, &p, &size, ANY_BUFFER))
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return NULL;
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if (i < 0) {
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i += size;
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}
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return buffer_item_impl(p, size, i);
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}
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else if (PySlice_Check(item)) {
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Py_ssize_t start, stop, step, slicelength, cur, i;
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if (_PySlice_Unpack(item, &start, &stop, &step) < 0)
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return NULL;
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if (!get_buf(self, &p, &size, ANY_BUFFER))
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return NULL;
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slicelength = _PySlice_AdjustIndices(size, &start, &stop, step);
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if (slicelength <= 0)
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return PyString_FromStringAndSize("", 0);
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else if (step == 1)
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return PyString_FromStringAndSize((char *)p + start,
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stop - start);
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else {
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PyObject *result;
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char *source_buf = (char *)p;
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char *result_buf = (char *)PyMem_Malloc(slicelength);
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if (result_buf == NULL)
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return PyErr_NoMemory();
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for (cur = start, i = 0; i < slicelength;
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cur += step, i++) {
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result_buf[i] = source_buf[cur];
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}
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result = PyString_FromStringAndSize(result_buf,
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slicelength);
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PyMem_Free(result_buf);
|
|
return result;
|
|
}
|
|
}
|
|
else {
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"sequence index must be integer");
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static int
|
|
buffer_ass_item_impl(void *ptr1, Py_ssize_t size, Py_ssize_t idx, PyObject *other)
|
|
{
|
|
PyBufferProcs *pb;
|
|
void *ptr2;
|
|
Py_ssize_t count;
|
|
|
|
if (idx < 0 || idx >= size) {
|
|
PyErr_SetString(PyExc_IndexError,
|
|
"buffer assignment index out of range");
|
|
return -1;
|
|
}
|
|
|
|
pb = other ? other->ob_type->tp_as_buffer : NULL;
|
|
if ( pb == NULL ||
|
|
pb->bf_getreadbuffer == NULL ||
|
|
pb->bf_getsegcount == NULL )
|
|
{
|
|
PyErr_BadArgument();
|
|
return -1;
|
|
}
|
|
if ( (*pb->bf_getsegcount)(other, NULL) != 1 )
|
|
{
|
|
/* ### use a different exception type/message? */
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"single-segment buffer object expected");
|
|
return -1;
|
|
}
|
|
|
|
if ( (count = (*pb->bf_getreadbuffer)(other, 0, &ptr2)) < 0 )
|
|
return -1;
|
|
if ( count != 1 ) {
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"right operand must be a single byte");
|
|
return -1;
|
|
}
|
|
|
|
((char *)ptr1)[idx] = *(char *)ptr2;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
buffer_ass_item(PyBufferObject *self, Py_ssize_t idx, PyObject *other)
|
|
{
|
|
void *ptr1;
|
|
Py_ssize_t size;
|
|
|
|
if ( self->b_readonly ) {
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"buffer is read-only");
|
|
return -1;
|
|
}
|
|
|
|
if (!get_buf(self, &ptr1, &size, ANY_BUFFER))
|
|
return -1;
|
|
return buffer_ass_item_impl(ptr1, size, idx, other);
|
|
}
|
|
|
|
static int
|
|
buffer_ass_slice(PyBufferObject *self, Py_ssize_t left, Py_ssize_t right, PyObject *other)
|
|
{
|
|
PyBufferProcs *pb;
|
|
void *ptr1, *ptr2;
|
|
Py_ssize_t size;
|
|
Py_ssize_t slice_len;
|
|
Py_ssize_t count;
|
|
|
|
if ( self->b_readonly ) {
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"buffer is read-only");
|
|
return -1;
|
|
}
|
|
|
|
pb = other ? other->ob_type->tp_as_buffer : NULL;
|
|
if ( pb == NULL ||
|
|
pb->bf_getreadbuffer == NULL ||
|
|
pb->bf_getsegcount == NULL )
|
|
{
|
|
PyErr_BadArgument();
|
|
return -1;
|
|
}
|
|
if ( (*pb->bf_getsegcount)(other, NULL) != 1 )
|
|
{
|
|
/* ### use a different exception type/message? */
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"single-segment buffer object expected");
|
|
return -1;
|
|
}
|
|
if (!get_buf(self, &ptr1, &size, ANY_BUFFER))
|
|
return -1;
|
|
if ( (count = (*pb->bf_getreadbuffer)(other, 0, &ptr2)) < 0 )
|
|
return -1;
|
|
|
|
if ( left < 0 )
|
|
left = 0;
|
|
else if ( left > size )
|
|
left = size;
|
|
if ( right < left )
|
|
right = left;
|
|
else if ( right > size )
|
|
right = size;
|
|
slice_len = right - left;
|
|
|
|
if ( count != slice_len ) {
|
|
PyErr_SetString(
|
|
PyExc_TypeError,
|
|
"right operand length must match slice length");
|
|
return -1;
|
|
}
|
|
|
|
if ( slice_len )
|
|
memcpy((char *)ptr1 + left, ptr2, slice_len);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
buffer_ass_subscript(PyBufferObject *self, PyObject *item, PyObject *value)
|
|
{
|
|
PyBufferProcs *pb;
|
|
void *ptr1, *ptr2;
|
|
Py_ssize_t selfsize;
|
|
Py_ssize_t othersize;
|
|
|
|
if ( self->b_readonly ) {
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"buffer is read-only");
|
|
return -1;
|
|
}
|
|
|
|
pb = value ? value->ob_type->tp_as_buffer : NULL;
|
|
if ( pb == NULL ||
|
|
pb->bf_getreadbuffer == NULL ||
|
|
pb->bf_getsegcount == NULL )
|
|
{
|
|
PyErr_BadArgument();
|
|
return -1;
|
|
}
|
|
if ( (*pb->bf_getsegcount)(value, NULL) != 1 )
|
|
{
|
|
/* ### use a different exception type/message? */
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"single-segment buffer object expected");
|
|
return -1;
|
|
}
|
|
if (PyIndex_Check(item)) {
|
|
Py_ssize_t i = PyNumber_AsSsize_t(item, PyExc_IndexError);
|
|
if (i == -1 && PyErr_Occurred())
|
|
return -1;
|
|
if (!get_buf(self, &ptr1, &selfsize, ANY_BUFFER))
|
|
return -1;
|
|
|
|
if (i < 0)
|
|
i += selfsize;
|
|
return buffer_ass_item_impl(ptr1, selfsize, i, value);
|
|
}
|
|
else if (PySlice_Check(item)) {
|
|
Py_ssize_t start, stop, step, slicelength;
|
|
|
|
if (_PySlice_Unpack(item, &start, &stop, &step) < 0)
|
|
return -1;
|
|
if (!get_buf(self, &ptr1, &selfsize, ANY_BUFFER))
|
|
return -1;
|
|
|
|
slicelength = _PySlice_AdjustIndices(selfsize, &start, &stop, step);
|
|
if ((othersize = (*pb->bf_getreadbuffer)(value, 0, &ptr2)) < 0)
|
|
return -1;
|
|
|
|
if (othersize != slicelength) {
|
|
PyErr_SetString(
|
|
PyExc_TypeError,
|
|
"right operand length must match slice length");
|
|
return -1;
|
|
}
|
|
|
|
if (slicelength == 0)
|
|
return 0;
|
|
else if (step == 1) {
|
|
memcpy((char *)ptr1 + start, ptr2, slicelength);
|
|
return 0;
|
|
}
|
|
else {
|
|
Py_ssize_t cur, i;
|
|
|
|
for (cur = start, i = 0; i < slicelength;
|
|
cur += step, i++) {
|
|
((char *)ptr1)[cur] = ((char *)ptr2)[i];
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
} else {
|
|
PyErr_SetString(PyExc_TypeError,
|
|
"buffer indices must be integers");
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* Buffer methods */
|
|
|
|
static Py_ssize_t
|
|
buffer_getreadbuf(PyBufferObject *self, Py_ssize_t idx, void **pp)
|
|
{
|
|
Py_ssize_t size;
|
|
if ( idx != 0 ) {
|
|
PyErr_SetString(PyExc_SystemError,
|
|
"accessing non-existent buffer segment");
|
|
return -1;
|
|
}
|
|
if (!get_buf(self, pp, &size, READ_BUFFER))
|
|
return -1;
|
|
return size;
|
|
}
|
|
|
|
static Py_ssize_t
|
|
buffer_getwritebuf(PyBufferObject *self, Py_ssize_t idx, void **pp)
|
|
{
|
|
Py_ssize_t size;
|
|
|
|
if ( self->b_readonly )
|
|
{
|
|
PyErr_SetString(PyExc_TypeError, "buffer is read-only");
|
|
return -1;
|
|
}
|
|
|
|
if ( idx != 0 ) {
|
|
PyErr_SetString(PyExc_SystemError,
|
|
"accessing non-existent buffer segment");
|
|
return -1;
|
|
}
|
|
if (!get_buf(self, pp, &size, WRITE_BUFFER))
|
|
return -1;
|
|
return size;
|
|
}
|
|
|
|
static Py_ssize_t
|
|
buffer_getsegcount(PyBufferObject *self, Py_ssize_t *lenp)
|
|
{
|
|
void *ptr;
|
|
Py_ssize_t size;
|
|
if (!get_buf(self, &ptr, &size, ANY_BUFFER))
|
|
return -1;
|
|
if (lenp)
|
|
*lenp = size;
|
|
return 1;
|
|
}
|
|
|
|
static Py_ssize_t
|
|
buffer_getcharbuf(PyBufferObject *self, Py_ssize_t idx, const char **pp)
|
|
{
|
|
void *ptr;
|
|
Py_ssize_t size;
|
|
if ( idx != 0 ) {
|
|
PyErr_SetString(PyExc_SystemError,
|
|
"accessing non-existent buffer segment");
|
|
return -1;
|
|
}
|
|
if (!get_buf(self, &ptr, &size, CHAR_BUFFER))
|
|
return -1;
|
|
*pp = (const char *)ptr;
|
|
return size;
|
|
}
|
|
|
|
static int buffer_getbuffer(PyBufferObject *self, Py_buffer *buf, int flags)
|
|
{
|
|
void *ptr;
|
|
Py_ssize_t size;
|
|
if (!get_buf(self, &ptr, &size, ANY_BUFFER))
|
|
return -1;
|
|
return PyBuffer_FillInfo(buf, (PyObject*)self, ptr, size,
|
|
self->b_readonly, flags);
|
|
}
|
|
|
|
static PySequenceMethods buffer_as_sequence = {
|
|
(lenfunc)buffer_length, /*sq_length*/
|
|
(binaryfunc)buffer_concat, /*sq_concat*/
|
|
(ssizeargfunc)buffer_repeat, /*sq_repeat*/
|
|
(ssizeargfunc)buffer_item, /*sq_item*/
|
|
(ssizessizeargfunc)buffer_slice, /*sq_slice*/
|
|
(ssizeobjargproc)buffer_ass_item, /*sq_ass_item*/
|
|
(ssizessizeobjargproc)buffer_ass_slice, /*sq_ass_slice*/
|
|
};
|
|
|
|
static PyMappingMethods buffer_as_mapping = {
|
|
(lenfunc)buffer_length,
|
|
(binaryfunc)buffer_subscript,
|
|
(objobjargproc)buffer_ass_subscript,
|
|
};
|
|
|
|
static PyBufferProcs buffer_as_buffer = {
|
|
(readbufferproc)buffer_getreadbuf,
|
|
(writebufferproc)buffer_getwritebuf,
|
|
(segcountproc)buffer_getsegcount,
|
|
(charbufferproc)buffer_getcharbuf,
|
|
(getbufferproc)buffer_getbuffer,
|
|
};
|
|
|
|
PyTypeObject PyBuffer_Type = {
|
|
PyVarObject_HEAD_INIT(&PyType_Type, 0)
|
|
"buffer",
|
|
sizeof(PyBufferObject),
|
|
0,
|
|
(destructor)buffer_dealloc, /* tp_dealloc */
|
|
0, /* tp_print */
|
|
0, /* tp_getattr */
|
|
0, /* tp_setattr */
|
|
(cmpfunc)buffer_compare, /* tp_compare */
|
|
(reprfunc)buffer_repr, /* tp_repr */
|
|
0, /* tp_as_number */
|
|
&buffer_as_sequence, /* tp_as_sequence */
|
|
&buffer_as_mapping, /* tp_as_mapping */
|
|
(hashfunc)buffer_hash, /* tp_hash */
|
|
0, /* tp_call */
|
|
(reprfunc)buffer_str, /* tp_str */
|
|
PyObject_GenericGetAttr, /* tp_getattro */
|
|
0, /* tp_setattro */
|
|
&buffer_as_buffer, /* tp_as_buffer */
|
|
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GETCHARBUFFER | Py_TPFLAGS_HAVE_NEWBUFFER, /* tp_flags */
|
|
buffer_doc, /* tp_doc */
|
|
0, /* tp_traverse */
|
|
0, /* tp_clear */
|
|
0, /* tp_richcompare */
|
|
0, /* tp_weaklistoffset */
|
|
0, /* tp_iter */
|
|
0, /* tp_iternext */
|
|
0, /* tp_methods */
|
|
0, /* tp_members */
|
|
0, /* tp_getset */
|
|
0, /* tp_base */
|
|
0, /* tp_dict */
|
|
0, /* tp_descr_get */
|
|
0, /* tp_descr_set */
|
|
0, /* tp_dictoffset */
|
|
0, /* tp_init */
|
|
0, /* tp_alloc */
|
|
buffer_new, /* tp_new */
|
|
};
|