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#include "Python.h"
static char xreadlines_doc [] =
"xreadlines(f)\n\
\n\
Return an xreadlines object for the file f.";
typedef struct {
PyObject_HEAD
PyObject *file;
PyObject *lines;
int lineslen;
int lineno;
int abslineno;
} PyXReadlinesObject;
staticforward PyTypeObject XReadlinesObject_Type;
static void
xreadlines_dealloc(PyXReadlinesObject *op) {
Py_XDECREF(op->file);
Py_XDECREF(op->lines);
PyObject_DEL(op);
}
/* A larger chunk size doesn't seem to make a difference */
#define CHUNKSIZE 8192
static PyXReadlinesObject *
newreadlinesobject(PyObject *file) {
PyXReadlinesObject *op;
op = PyObject_NEW(PyXReadlinesObject, &XReadlinesObject_Type);
if (op == NULL)
return NULL;
Py_XINCREF(file);
op->file = file;
op->lines = NULL;
op->abslineno = op->lineno = op->lineslen = 0;
return op;
}
static PyObject *
xreadlines(PyObject *self, PyObject *args) {
PyObject *file;
PyXReadlinesObject *ret;
if (!PyArg_ParseTuple(args, "O:xreadlines", &file))
return NULL;
ret = newreadlinesobject(file);
Py_XINCREF(ret);
return (PyObject*)ret;
}
static PyObject*
xreadlines_item(PyXReadlinesObject *a, int i) {
if (i != a->abslineno) {
PyErr_SetString(PyExc_RuntimeError,
"xreadlines object accessed out of order");
return NULL;
}
if (a->lineno >= a->lineslen) {
Py_XDECREF(a->lines);
a->lines = PyObject_CallMethod(a->file, "readlines", "(i)",
CHUNKSIZE);
if (a->lines == NULL)
return NULL;
a->lineno = 0;
if ((a->lineslen = PySequence_Size(a->lines)) < 0)
return NULL;
}
a->abslineno++;
return PySequence_GetItem(a->lines, a->lineno++);
}
static PySequenceMethods xreadlines_as_sequence = {
0, /*sq_length*/
0, /*sq_concat*/
0, /*sq_repeat*/
(intargfunc)xreadlines_item, /*sq_item*/
};
static PyTypeObject XReadlinesObject_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0,
"xreadlines",
sizeof(PyXReadlinesObject) + PyGC_HEAD_SIZE,
0,
(destructor)xreadlines_dealloc, /*tp_dealloc*/
0, /*tp_print*/
0, /*tp_getattr*/
0, /*tp_setattr*/
0, /*tp_compare*/
0, /*tp_repr*/
0, /*tp_as_number*/
&xreadlines_as_sequence, /*tp_as_sequence*/
0, /*tp_as_mapping*/
0, /*tp_hash*/
0, /*tp_call*/
0, /*tp_str*/
0, /*tp_getattro*/
0, /*tp_setattro*/
0, /*tp_as_buffer*/
Py_TPFLAGS_DEFAULT, /*tp_flags*/
0, /* tp_doc */
};
static PyMethodDef xreadlines_methods[] = {
{"xreadlines", xreadlines, METH_VARARGS, xreadlines_doc},
{NULL, NULL}
};
void
initxreadlines(void)
{
PyObject *m;
m = Py_InitModule("xreadlines", xreadlines_methods);
}
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