cpython/Modules/_io/bytesio.c at pythoncapi · pythoncapi/cpython · GitHub

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#include "Python.h"

#include "structmember.h" /* for offsetof() */

#include "_iomodule.h"

/*[clinic input]

module _io

class _io.BytesIO "bytesio *" "&PyBytesIO_Type"

[clinic start generated code]*/

/*[clinic end generated code: output=da39a3ee5e6b4b0d input=7f50ec034f5c0b26]*/

typedef struct {

PyObject_HEAD

PyObject *buf;

Py_ssize_t pos;

Py_ssize_t string_size;

PyObject *dict;

PyObject *weakreflist;

Py_ssize_t exports;

} bytesio;

typedef struct {

PyObject_HEAD

bytesio *source;

} bytesiobuf;

/* The bytesio object can be in three states:

* Py_REFCNT(buf) == 1, exports == 0.

* Py_REFCNT(buf) > 1. exports == 0,

first modification or export causes the internal buffer copying.

* exports > 0. Py_REFCNT(buf) == 1, any modifications are forbidden.

#define CHECK_CLOSED(self) \

if ((self)->buf == NULL) { \

PyErr_SetString(PyExc_ValueError, \

"I/O operation on closed file."); \

return NULL; \

}

#define CHECK_EXPORTS(self) \

if ((self)->exports > 0) { \

PyErr_SetString(PyExc_BufferError, \

"Existing exports of data: object cannot be re-sized"); \

return NULL; \

}

#define SHARED_BUF(self) (Py_REFCNT((self)->buf) > 1)

/* Internal routine to get a line from the buffer of a BytesIO

object. Returns the length between the current position to the

next newline character. */

static Py_ssize_t

scan_eol(bytesio *self, Py_ssize_t len)

{

const char *start, *n;

Py_ssize_t maxlen;

assert(self->buf != NULL);

assert(self->pos >= 0);

if (self->pos >= self->string_size)

return 0;

/* Move to the end of the line, up to the end of the string, s. */

maxlen = self->string_size - self->pos;

if (len < 0 || len > maxlen)

len = maxlen;

if (len) {

start = PyBytes_AS_STRING(self->buf) + self->pos;

n = memchr(start, '\n', len);

if (n)

/* Get the length from the current position to the end of

the line. */

len = n - start + 1;

}

assert(len >= 0);

assert(self->pos < PY_SSIZE_T_MAX - len);

return len;

}

/* Internal routine for detaching the shared buffer of BytesIO objects.

The caller should ensure that the 'size' argument is non-negative and

not lesser than self->string_size. Returns 0 on success, -1 otherwise. */

static int

unshare_buffer(bytesio *self, size_t size)

{

PyObject *new_buf;

assert(SHARED_BUF(self));

assert(self->exports == 0);

assert(size >= (size_t)self->string_size);

new_buf = PyBytes_FromStringAndSize(NULL, size);

if (new_buf == NULL)

return -1;

memcpy(PyBytes_AS_STRING(new_buf), PyBytes_AS_STRING(self->buf),

self->string_size);

Py_SETREF(self->buf, new_buf);

return 0;

}

/* Internal routine for changing the size of the buffer of BytesIO objects.

The caller should ensure that the 'size' argument is non-negative. Returns

0 on success, -1 otherwise. */

static int

resize_buffer(bytesio *self, size_t size)

{

/* Here, unsigned types are used to avoid dealing with signed integer

overflow, which is undefined in C. */

size_t alloc = PyBytes_GET_SIZE(self->buf);

assert(self->buf != NULL);

/* For simplicity, stay in the range of the signed type. Anyway, Python

doesn't allow strings to be longer than this. */

if (size > PY_SSIZE_T_MAX)

goto overflow;

if (size < alloc / 2) {

/* Major downsize; resize down to exact size. */

alloc = size + 1;

}

else if (size < alloc) {

/* Within allocated size; quick exit */

return 0;

}

else if (size <= alloc * 1.125) {

/* Moderate upsize; overallocate similar to list_resize() */

alloc = size + (size >> 3) + (size < 9 ? 3 : 6);

}

else {

/* Major upsize; resize up to exact size */

alloc = size + 1;

}

if (alloc > ((size_t)-1) / sizeof(char))

goto overflow;

if (SHARED_BUF(self)) {

if (unshare_buffer(self, alloc) < 0)

return -1;

}

else {

if (_PyBytes_Resize(&self->buf, alloc) < 0)

return -1;

}

return 0;

overflow:

PyErr_SetString(PyExc_OverflowError,

"new buffer size too large");

return -1;

}

/* Internal routine for writing a string of bytes to the buffer of a BytesIO

object. Returns the number of bytes written, or -1 on error. */

static Py_ssize_t

write_bytes(bytesio *self, const char *bytes, Py_ssize_t len)

{

size_t endpos;

assert(self->buf != NULL);

assert(self->pos >= 0);

assert(len >= 0);

endpos = (size_t)self->pos + len;

if (endpos > (size_t)PyBytes_GET_SIZE(self->buf)) {

if (resize_buffer(self, endpos) < 0)

return -1;

}

else if (SHARED_BUF(self)) {

if (unshare_buffer(self, Py_MAX(endpos, (size_t)self->string_size)) < 0)

return -1;

}

if (self->pos > self->string_size) {

/* In case of overseek, pad with null bytes the buffer region between

the end of stream and the current position.

0 lo string_size hi

| |<---used--->|<----------available----------->|

| | <--to pad-->|<---to write---> |

0 buf position

memset(PyBytes_AS_STRING(self->buf) + self->string_size, '\0',

(self->pos - self->string_size) * sizeof(char));

}

/* Copy the data to the internal buffer, overwriting some of the existing

data if self->pos < self->string_size. */

memcpy(PyBytes_AS_STRING(self->buf) + self->pos, bytes, len);

self->pos = endpos;

/* Set the new length of the internal string if it has changed. */

if ((size_t)self->string_size < endpos) {

self->string_size = endpos;

}

return len;

}

static PyObject *

bytesio_get_closed(bytesio *self)

{

if (self->buf == NULL) {

Py_RETURN_TRUE;

}

else {

Py_RETURN_FALSE;

}

/*[clinic input]

_io.BytesIO.readable

Returns True if the IO object can be read.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_readable_impl(bytesio *self)

/*[clinic end generated code: output=4e93822ad5b62263 input=96c5d0cccfb29f5c]*/

{

CHECK_CLOSED(self);

Py_RETURN_TRUE;

}

/*[clinic input]

_io.BytesIO.writable

Returns True if the IO object can be written.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_writable_impl(bytesio *self)

/*[clinic end generated code: output=64ff6a254b1150b8 input=700eed808277560a]*/

{

CHECK_CLOSED(self);

Py_RETURN_TRUE;

}

/*[clinic input]

_io.BytesIO.seekable

Returns True if the IO object can be seeked.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_seekable_impl(bytesio *self)

/*[clinic end generated code: output=6b417f46dcc09b56 input=9421f65627a344dd]*/

{

CHECK_CLOSED(self);

Py_RETURN_TRUE;

}

/*[clinic input]

_io.BytesIO.flush

Does nothing.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_flush_impl(bytesio *self)

/*[clinic end generated code: output=187e3d781ca134a0 input=561ea490be4581a7]*/

{

CHECK_CLOSED(self);

Py_RETURN_NONE;

}

/*[clinic input]

_io.BytesIO.getbuffer

Get a read-write view over the contents of the BytesIO object.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_getbuffer_impl(bytesio *self)

/*[clinic end generated code: output=72cd7c6e13aa09ed input=8f738ef615865176]*/

{

PyTypeObject *type = &_PyBytesIOBuffer_Type;

bytesiobuf *buf;

PyObject *view;

CHECK_CLOSED(self);

buf = (bytesiobuf *) type->tp_alloc(type, 0);

if (buf == NULL)

return NULL;

Py_INCREF(self);

buf->source = self;

view = PyMemoryView_FromObject((PyObject *) buf);

Py_DECREF(buf);

return view;

}

/*[clinic input]

_io.BytesIO.getvalue

Retrieve the entire contents of the BytesIO object.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_getvalue_impl(bytesio *self)

/*[clinic end generated code: output=b3f6a3233c8fd628 input=4b403ac0af3973ed]*/

{

CHECK_CLOSED(self);

if (self->string_size <= 1 || self->exports > 0)

return PyBytes_FromStringAndSize(PyBytes_AS_STRING(self->buf),

self->string_size);

if (self->string_size != PyBytes_GET_SIZE(self->buf)) {

if (SHARED_BUF(self)) {

if (unshare_buffer(self, self->string_size) < 0)

return NULL;

}

else {

if (_PyBytes_Resize(&self->buf, self->string_size) < 0)

return NULL;

}

Py_INCREF(self->buf);

return self->buf;

}

/*[clinic input]

_io.BytesIO.isatty

Always returns False.

BytesIO objects are not connected to a TTY-like device.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_isatty_impl(bytesio *self)

/*[clinic end generated code: output=df67712e669f6c8f input=6f97f0985d13f827]*/

{

CHECK_CLOSED(self);

Py_RETURN_FALSE;

}

/*[clinic input]

_io.BytesIO.tell

Current file position, an integer.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_tell_impl(bytesio *self)

/*[clinic end generated code: output=b54b0f93cd0e5e1d input=b106adf099cb3657]*/

{

CHECK_CLOSED(self);

return PyLong_FromSsize_t(self->pos);

}

static PyObject *

read_bytes(bytesio *self, Py_ssize_t size)

{

char *output;

assert(self->buf != NULL);

assert(size <= self->string_size);

if (size > 1 &&

self->pos == 0 && size == PyBytes_GET_SIZE(self->buf) &&

self->exports == 0) {

self->pos += size;

Py_INCREF(self->buf);

return self->buf;

}

output = PyBytes_AS_STRING(self->buf) + self->pos;

self->pos += size;

return PyBytes_FromStringAndSize(output, size);

}

/*[clinic input]

_io.BytesIO.read

size: Py_ssize_t(accept={int, NoneType}) = -1

Read at most size bytes, returned as a bytes object.

If the size argument is negative, read until EOF is reached.

Return an empty bytes object at EOF.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_read_impl(bytesio *self, Py_ssize_t size)

/*[clinic end generated code: output=9cc025f21c75bdd2 input=74344a39f431c3d7]*/

{

Py_ssize_t n;

CHECK_CLOSED(self);

/* adjust invalid sizes */

n = self->string_size - self->pos;

if (size < 0 || size > n) {

size = n;

if (size < 0)

size = 0;

}

return read_bytes(self, size);

}

/*[clinic input]

_io.BytesIO.read1

size: Py_ssize_t(accept={int, NoneType}) = -1

Read at most size bytes, returned as a bytes object.

If the size argument is negative or omitted, read until EOF is reached.

Return an empty bytes object at EOF.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_read1_impl(bytesio *self, Py_ssize_t size)

/*[clinic end generated code: output=d0f843285aa95f1c input=440a395bf9129ef5]*/

{

return _io_BytesIO_read_impl(self, size);

}

/*[clinic input]

_io.BytesIO.readline

size: Py_ssize_t(accept={int, NoneType}) = -1

Next line from the file, as a bytes object.

Retain newline. A non-negative size argument limits the maximum

number of bytes to return (an incomplete line may be returned then).

Return an empty bytes object at EOF.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_readline_impl(bytesio *self, Py_ssize_t size)

/*[clinic end generated code: output=4bff3c251df8ffcd input=e7c3fbd1744e2783]*/

{

Py_ssize_t n;

CHECK_CLOSED(self);

n = scan_eol(self, size);

return read_bytes(self, n);

}

/*[clinic input]

_io.BytesIO.readlines

size as arg: object = None

List of bytes objects, each a line from the file.

Call readline() repeatedly and return a list of the lines so read.

The optional size argument, if given, is an approximate bound on the

total number of bytes in the lines returned.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_readlines_impl(bytesio *self, PyObject *arg)

/*[clinic end generated code: output=09b8e34c880808ff input=691aa1314f2c2a87]*/

{

Py_ssize_t maxsize, size, n;

PyObject *result, *line;

char *output;

CHECK_CLOSED(self);

if (PyLong_Check(arg)) {

maxsize = PyLong_AsSsize_t(arg);

if (maxsize == -1 && PyErr_Occurred())

return NULL;

}

else if (arg == Py_None) {

/* No size limit, by default. */

maxsize = -1;

}

else {

PyErr_Format(PyExc_TypeError, "integer argument expected, got '%s'",

Py_TYPE(arg)->tp_name);

return NULL;

}

size = 0;

result = PyList_New(0);

if (!result)

return NULL;

output = PyBytes_AS_STRING(self->buf) + self->pos;

while ((n = scan_eol(self, -1)) != 0) {

self->pos += n;

line = PyBytes_FromStringAndSize(output, n);

if (!line)

goto on_error;

if (PyList_Append(result, line) == -1) {

Py_DECREF(line);

goto on_error;

}

Py_DECREF(line);

size += n;

if (maxsize > 0 && size >= maxsize)

break;

output += n;

}

return result;

on_error:

Py_DECREF(result);

return NULL;

}

/*[clinic input]

_io.BytesIO.readinto

buffer: Py_buffer(accept={rwbuffer})

Read bytes into buffer.

Returns number of bytes read (0 for EOF), or None if the object

is set not to block and has no data to read.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_readinto_impl(bytesio *self, Py_buffer *buffer)

/*[clinic end generated code: output=a5d407217dcf0639 input=1424d0fdce857919]*/

{

Py_ssize_t len, n;

CHECK_CLOSED(self);

/* adjust invalid sizes */

len = buffer->len;

n = self->string_size - self->pos;

if (len > n) {

len = n;

if (len < 0)

len = 0;

}

memcpy(buffer->buf, PyBytes_AS_STRING(self->buf) + self->pos, len);

assert(self->pos + len < PY_SSIZE_T_MAX);

assert(len >= 0);

self->pos += len;

return PyLong_FromSsize_t(len);

}

/*[clinic input]

_io.BytesIO.truncate

size: Py_ssize_t(accept={int, NoneType}, c_default="self->pos") = None

Truncate the file to at most size bytes.

Size defaults to the current file position, as returned by tell().

The current file position is unchanged. Returns the new size.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_truncate_impl(bytesio *self, Py_ssize_t size)

/*[clinic end generated code: output=9ad17650c15fa09b input=423759dd42d2f7c1]*/

{

CHECK_CLOSED(self);

CHECK_EXPORTS(self);

if (size < 0) {

PyErr_Format(PyExc_ValueError,

"negative size value %zd", size);

return NULL;

}

if (size < self->string_size) {

self->string_size = size;

if (resize_buffer(self, size) < 0)

return NULL;

}

return PyLong_FromSsize_t(size);

}

static PyObject *

bytesio_iternext(bytesio *self)

{

Py_ssize_t n;

CHECK_CLOSED(self);

n = scan_eol(self, -1);

if (n == 0)

return NULL;

return read_bytes(self, n);

}

/*[clinic input]

_io.BytesIO.seek

pos: Py_ssize_t

whence: int = 0

Change stream position.

Seek to byte offset pos relative to position indicated by whence:

0 Start of stream (the default). pos should be >= 0;

1 Current position - pos may be negative;

2 End of stream - pos usually negative.

Returns the new absolute position.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_seek_impl(bytesio *self, Py_ssize_t pos, int whence)

/*[clinic end generated code: output=c26204a68e9190e4 input=1e875e6ebc652948]*/

{

CHECK_CLOSED(self);

if (pos < 0 && whence == 0) {

PyErr_Format(PyExc_ValueError,

"negative seek value %zd", pos);

return NULL;

}

/* whence = 0: offset relative to beginning of the string.

whence = 1: offset relative to current position.

whence = 2: offset relative the end of the string. */

if (whence == 1) {

if (pos > PY_SSIZE_T_MAX - self->pos) {

PyErr_SetString(PyExc_OverflowError,

"new position too large");

return NULL;

}

pos += self->pos;

}

else if (whence == 2) {

if (pos > PY_SSIZE_T_MAX - self->string_size) {

PyErr_SetString(PyExc_OverflowError,

"new position too large");

return NULL;

}

pos += self->string_size;

}

else if (whence != 0) {

PyErr_Format(PyExc_ValueError,

"invalid whence (%i, should be 0, 1 or 2)", whence);

return NULL;

}

if (pos < 0)

pos = 0;

self->pos = pos;

return PyLong_FromSsize_t(self->pos);

}

/*[clinic input]

_io.BytesIO.write

b: object

Write bytes to file.

Return the number of bytes written.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_write(bytesio *self, PyObject *b)

/*[clinic end generated code: output=53316d99800a0b95 input=f5ec7c8c64ed720a]*/

{

Py_ssize_t n = 0;

Py_buffer buf;

CHECK_CLOSED(self);

CHECK_EXPORTS(self);

if (PyObject_GetBuffer(b, &buf, PyBUF_CONTIG_RO) < 0)

return NULL;

if (buf.len != 0)

n = write_bytes(self, buf.buf, buf.len);

PyBuffer_Release(&buf);

return n >= 0 ? PyLong_FromSsize_t(n) : NULL;

}

/*[clinic input]

_io.BytesIO.writelines

lines: object

Write lines to the file.

Note that newlines are not added. lines can be any iterable object

producing bytes-like objects. This is equivalent to calling write() for

each element.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_writelines(bytesio *self, PyObject *lines)

/*[clinic end generated code: output=7f33aa3271c91752 input=e972539176fc8fc1]*/

{

PyObject *it, *item;

PyObject *ret;

CHECK_CLOSED(self);

it = PyObject_GetIter(lines);

if (it == NULL)

return NULL;

while ((item = PyIter_Next(it)) != NULL) {

ret = _io_BytesIO_write(self, item);

Py_DECREF(item);

if (ret == NULL) {

Py_DECREF(it);

return NULL;

}

Py_DECREF(ret);

}

Py_DECREF(it);

/* See if PyIter_Next failed */

if (PyErr_Occurred())

return NULL;

Py_RETURN_NONE;

}

/*[clinic input]

_io.BytesIO.close

Disable all I/O operations.

[clinic start generated code]*/

static PyObject *

_io_BytesIO_close_impl(bytesio *self)

/*[clinic end generated code: output=1471bb9411af84a0 input=37e1f55556e61f60]*/

{

CHECK_EXPORTS(self);

Py_CLEAR(self->buf);

Py_RETURN_NONE;

}

/* Pickling support.

Note that only pickle protocol 2 and onward are supported since we use

extended __reduce__ API of PEP 307 to make BytesIO instances picklable.

Providing support for protocol < 2 would require the __reduce_ex__ method

which is notably long-winded when defined properly.

For BytesIO, the implementation would similar to one coded for

object.__reduce_ex__, but slightly less general. To be more specific, we

could call bytesio_getstate directly and avoid checking for the presence of

a fallback __reduce__ method. However, we would still need a __newobj__

function to use the efficient instance representation of PEP 307.

static PyObject *

bytesio_getstate(bytesio *self, PyObject *Py_UNUSED(ignored))

{

PyObject *initvalue = _io_BytesIO_getvalue_impl(self);

PyObject *dict;

PyObject *state;

if (initvalue == NULL)

return NULL;

if (self->dict == NULL) {

Py_INCREF(Py_None);

dict = Py_None;

}

else {

dict = PyDict_Copy(self->dict);

if (dict == NULL) {

Py_DECREF(initvalue);

return NULL;

}

state = Py_BuildValue("(OnN)", initvalue, self->pos, dict);

Py_DECREF(initvalue);

return state;

}

static PyObject *

bytesio_setstate(bytesio *self, PyObject *state)

{

PyObject *result;

PyObject *position_obj;

PyObject *dict;

Py_ssize_t pos;

assert(state != NULL);

/* We allow the state tuple to be longer than 3, because we may need

someday to extend the object's state without breaking

backward-compatibility. */

if (!PyTuple_Check(state) || PyTuple_GET_SIZE(state) < 3) {

PyErr_Format(PyExc_TypeError,

"%.200s.__setstate__ argument should be 3-tuple, got %.200s",

Py_TYPE(self)->tp_name, Py_TYPE(state)->tp_name);

return NULL;

}

CHECK_EXPORTS(self);

/* Reset the object to its default state. This is only needed to handle

the case of repeated calls to __setstate__. */

self->string_size = 0;

self->pos = 0;

/* Set the value of the internal buffer. If state[0] does not support the

buffer protocol, bytesio_write will raise the appropriate TypeError. */

result = _io_BytesIO_write(self, PyTuple_GET_ITEM(state, 0));

if (result == NULL)

return NULL;

Py_DECREF(result);

/* Set carefully the position value. Alternatively, we could use the seek

method instead of modifying self->pos directly to better protect the

object internal state against errneous (or malicious) inputs. */

position_obj = PyTuple_GET_ITEM(state, 1);

if (!PyLong_Check(position_obj)) {

PyErr_Format(PyExc_TypeError,

"second item of state must be an integer, not %.200s",

Py_TYPE(position_obj)->tp_name);

return NULL;

}

pos = PyLong_AsSsize_t(position_obj);

if (pos == -1 && PyErr_Occurred())

return NULL;

if (pos < 0) {

PyErr_SetString(PyExc_ValueError,

"position value cannot be negative");

return NULL;

}

self->pos = pos;

/* Set the dictionary of the instance variables. */

dict = PyTuple_GET_ITEM(state, 2);

if (dict != Py_None) {

if (!PyDict_Check(dict)) {

PyErr_Format(PyExc_TypeError,

"third item of state should be a dict, got a %.200s",

Py_TYPE(dict)->tp_name);

return NULL;

}

if (self->dict) {

/* Alternatively, we could replace the internal dictionary

completely. However, it seems more practical to just update it. */

if (PyDict_Update(self->dict, dict) < 0)

return NULL;

}

else {

Py_INCREF(dict);

self->dict = dict;

}

Py_RETURN_NONE;

}

static void

bytesio_dealloc(bytesio *self)

{

_PyObject_GC_UNTRACK(self);

if (self->exports > 0) {

PyErr_SetString(PyExc_SystemError,

"deallocated BytesIO object has exported buffers");

PyErr_Print();

}

Py_CLEAR(self->buf);

Py_CLEAR(self->dict);

if (self->weakreflist != NULL)

PyObject_ClearWeakRefs((PyObject *) self);

Py_TYPE(self)->tp_free(self);

}

static PyObject *

bytesio_new(PyTypeObject *type, PyObject *args, PyObject *kwds)

{

bytesio *self;

assert(type != NULL && type->tp_alloc != NULL);

self = (bytesio *)type->tp_alloc(type, 0);

if (self == NULL)

return NULL;

/* tp_alloc initializes all the fields to zero. So we don't have to

initialize them here. */

self->buf = PyBytes_FromStringAndSize(NULL, 0);

if (self->buf == NULL) {

Py_DECREF(self);

return PyErr_NoMemory();

}

return (PyObject *)self;

}

/*[clinic input]

_io.BytesIO.__init__

initial_bytes as initvalue: object(c_default="NULL") = b''

Buffered I/O implementation using an in-memory bytes buffer.

[clinic start generated code]*/

static int

_io_BytesIO___init___impl(bytesio *self, PyObject *initvalue)

/*[clinic end generated code: output=65c0c51e24c5b621 input=aac7f31b67bf0fb6]*/

{

/* In case, __init__ is called multiple times. */

self->string_size = 0;

self->pos = 0;

if (self->exports > 0) {

PyErr_SetString(PyExc_BufferError,

"Existing exports of data: object cannot be re-sized");

return -1;

}

if (initvalue && initvalue != Py_None) {

if (PyBytes_CheckExact(initvalue)) {

Py_INCREF(initvalue);

Py_XSETREF(self->buf, initvalue);

self->string_size = PyBytes_GET_SIZE(initvalue);

}

else {

PyObject *res;

res = _io_BytesIO_write(self, initvalue);

if (res == NULL)

return -1;

Py_DECREF(res);

self->pos = 0;

}

return 0;

}

static PyObject *

bytesio_sizeof(bytesio *self, void *unused)

{

Py_ssize_t res;

res = _PyObject_SIZE(Py_TYPE(self));

if (self->buf && !SHARED_BUF(self))

res += _PySys_GetSizeOf(self->buf);

return PyLong_FromSsize_t(res);

}

static int

bytesio_traverse(bytesio *self, visitproc visit, void *arg)

{

Py_VISIT(self->dict);

return 0;

}

static int

bytesio_clear(bytesio *self)

{

Py_CLEAR(self->dict);

return 0;

}

#include "clinic/bytesio.c.h"

static PyGetSetDef bytesio_getsetlist[] = {

{"closed", (getter)bytesio_get_closed, NULL,

"True if the file is closed."},

{NULL}, /* sentinel */

};

static struct PyMethodDef bytesio_methods[] = {

_IO_BYTESIO_READABLE_METHODDEF

_IO_BYTESIO_SEEKABLE_METHODDEF

_IO_BYTESIO_WRITABLE_METHODDEF

_IO_BYTESIO_CLOSE_METHODDEF

_IO_BYTESIO_FLUSH_METHODDEF

_IO_BYTESIO_ISATTY_METHODDEF

_IO_BYTESIO_TELL_METHODDEF

_IO_BYTESIO_WRITE_METHODDEF

_IO_BYTESIO_WRITELINES_METHODDEF

_IO_BYTESIO_READ1_METHODDEF

_IO_BYTESIO_READINTO_METHODDEF

_IO_BYTESIO_READLINE_METHODDEF

_IO_BYTESIO_READLINES_METHODDEF

_IO_BYTESIO_READ_METHODDEF

_IO_BYTESIO_GETBUFFER_METHODDEF

_IO_BYTESIO_GETVALUE_METHODDEF

_IO_BYTESIO_SEEK_METHODDEF

_IO_BYTESIO_TRUNCATE_METHODDEF

{"__getstate__", (PyCFunction)bytesio_getstate, METH_NOARGS, NULL},

{"__setstate__", (PyCFunction)bytesio_setstate, METH_O, NULL},

{"__sizeof__", (PyCFunction)bytesio_sizeof, METH_NOARGS, NULL},

{NULL, NULL} /* sentinel */

};

PyTypeObject PyBytesIO_Type = {

PyVarObject_HEAD_INIT(NULL, 0)

"_io.BytesIO", /*tp_name*/

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cpython/Modules/_io/bytesio.c at pythoncapi · pythoncapi/cpython · GitHub

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