_iomodule.c 24.7 KB
Newer Older
1 2
/*
    An implementation of the new I/O lib as defined by PEP 3116 - "New I/O"
3

4 5
    Classes defined here: UnsupportedOperation, BlockingIOError.
    Functions defined here: open().
6

7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
    Mostly written by Amaury Forgeot d'Arc
*/

#define PY_SSIZE_T_CLEAN
#include "Python.h"
#include "structmember.h"
#include "_iomodule.h"

#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif /* HAVE_SYS_TYPES_H */

#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif /* HAVE_SYS_STAT_H */


/* Various interned strings */

PyObject *_PyIO_str_close;
PyObject *_PyIO_str_closed;
PyObject *_PyIO_str_decode;
PyObject *_PyIO_str_encode;
PyObject *_PyIO_str_fileno;
PyObject *_PyIO_str_flush;
PyObject *_PyIO_str_getstate;
PyObject *_PyIO_str_isatty;
PyObject *_PyIO_str_newlines;
PyObject *_PyIO_str_nl;
PyObject *_PyIO_str_read;
PyObject *_PyIO_str_read1;
PyObject *_PyIO_str_readable;
39
PyObject *_PyIO_str_readall;
40 41 42 43 44
PyObject *_PyIO_str_readinto;
PyObject *_PyIO_str_readline;
PyObject *_PyIO_str_reset;
PyObject *_PyIO_str_seek;
PyObject *_PyIO_str_seekable;
45
PyObject *_PyIO_str_setstate;
46 47 48 49 50 51 52
PyObject *_PyIO_str_tell;
PyObject *_PyIO_str_truncate;
PyObject *_PyIO_str_writable;
PyObject *_PyIO_str_write;

PyObject *_PyIO_empty_str;
PyObject *_PyIO_empty_bytes;
53
PyObject *_PyIO_zero;
54 55 56 57 58 59 60 61


PyDoc_STRVAR(module_doc,
"The io module provides the Python interfaces to stream handling. The\n"
"builtin open function is defined in this module.\n"
"\n"
"At the top of the I/O hierarchy is the abstract base class IOBase. It\n"
"defines the basic interface to a stream. Note, however, that there is no\n"
62
"separation between reading and writing to streams; implementations are\n"
63
"allowed to raise an IOError if they do not support a given operation.\n"
64 65
"\n"
"Extending IOBase is RawIOBase which deals simply with the reading and\n"
Benjamin Peterson's avatar
Benjamin Peterson committed
66
"writing of raw bytes to a stream. FileIO subclasses RawIOBase to provide\n"
67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96
"an interface to OS files.\n"
"\n"
"BufferedIOBase deals with buffering on a raw byte stream (RawIOBase). Its\n"
"subclasses, BufferedWriter, BufferedReader, and BufferedRWPair buffer\n"
"streams that are readable, writable, and both respectively.\n"
"BufferedRandom provides a buffered interface to random access\n"
"streams. BytesIO is a simple stream of in-memory bytes.\n"
"\n"
"Another IOBase subclass, TextIOBase, deals with the encoding and decoding\n"
"of streams into text. TextIOWrapper, which extends it, is a buffered text\n"
"interface to a buffered raw stream (`BufferedIOBase`). Finally, StringIO\n"
"is a in-memory stream for text.\n"
"\n"
"Argument names are not part of the specification, and only the arguments\n"
"of open() are intended to be used as keyword arguments.\n"
"\n"
"data:\n"
"\n"
"DEFAULT_BUFFER_SIZE\n"
"\n"
"   An int containing the default buffer size used by the module's buffered\n"
"   I/O classes. open() uses the file's blksize (as obtained by os.stat) if\n"
"   possible.\n"
    );


/*
 * The main open() function
 */
PyDoc_STRVAR(open_doc,
97
"open(file, mode='r', buffering=-1, encoding=None,\n"
98
"     errors=None, newline=None, closefd=True, opener=None) -> file object\n"
99
"\n"
100 101 102 103 104 105 106 107 108 109 110
"Open file and return a stream.  Raise IOError upon failure.\n"
"\n"
"file is either a text or byte string giving the name (and the path\n"
"if the file isn't in the current working directory) of the file to\n"
"be opened or an integer file descriptor of the file to be\n"
"wrapped. (If a file descriptor is given, it is closed when the\n"
"returned I/O object is closed, unless closefd is set to False.)\n"
"\n"
"mode is an optional string that specifies the mode in which the file\n"
"is opened. It defaults to 'r' which means open for reading in text\n"
"mode.  Other common values are 'w' for writing (truncating the file if\n"
111 112 113 114
"it already exists), 'x' for creating and writing to a new file, and\n"
"'a' for appending (which on some Unix systems, means that all writes\n"
"append to the end of the file regardless of the current seek position).\n"
"In text mode, if encoding is not specified the encoding used is platform\n"
115 116 117
"dependent: locale.getpreferredencoding(False) is called to get the\n"
"current locale encoding. (For reading and writing raw bytes use binary\n"
"mode and leave encoding unspecified.) The available modes are:\n"
118 119 120 121 122 123
"\n"
"========= ===============================================================\n"
"Character Meaning\n"
"--------- ---------------------------------------------------------------\n"
"'r'       open for reading (default)\n"
"'w'       open for writing, truncating the file first\n"
124
"'x'       create a new file and open it for writing\n"
125 126 127 128
"'a'       open for writing, appending to the end of the file if it exists\n"
"'b'       binary mode\n"
"'t'       text mode (default)\n"
"'+'       open a disk file for updating (reading and writing)\n"
129
"'U'       universal newline mode (deprecated)\n"
130 131 132 133
"========= ===============================================================\n"
"\n"
"The default mode is 'rt' (open for reading text). For binary random\n"
"access, the mode 'w+b' opens and truncates the file to 0 bytes, while\n"
134 135
"'r+b' opens the file without truncation. The 'x' mode implies 'w' and\n"
"raises an `FileExistsError` if the file already exists.\n"
136 137 138 139 140 141 142 143 144
"\n"
"Python distinguishes between files opened in binary and text modes,\n"
"even when the underlying operating system doesn't. Files opened in\n"
"binary mode (appending 'b' to the mode argument) return contents as\n"
"bytes objects without any decoding. In text mode (the default, or when\n"
"'t' is appended to the mode argument), the contents of the file are\n"
"returned as strings, the bytes having been first decoded using a\n"
"platform-dependent encoding or using the specified encoding if given.\n"
"\n"
145 146 147 148
"'U' mode is deprecated and will raise an exception in future versions\n"
"of Python.  It has no effect in Python 3.  Use newline to control\n"
"universal newlines mode.\n"
"\n"
149 150 151 152 153 154 155 156 157 158 159 160 161 162
"buffering is an optional integer used to set the buffering policy.\n"
"Pass 0 to switch buffering off (only allowed in binary mode), 1 to select\n"
"line buffering (only usable in text mode), and an integer > 1 to indicate\n"
"the size of a fixed-size chunk buffer.  When no buffering argument is\n"
"given, the default buffering policy works as follows:\n"
"\n"
"* Binary files are buffered in fixed-size chunks; the size of the buffer\n"
"  is chosen using a heuristic trying to determine the underlying device's\n"
"  \"block size\" and falling back on `io.DEFAULT_BUFFER_SIZE`.\n"
"  On many systems, the buffer will typically be 4096 or 8192 bytes long.\n"
"\n"
"* \"Interactive\" text files (files for which isatty() returns True)\n"
"  use line buffering.  Other text files use the policy described above\n"
"  for binary files.\n"
163 164 165 166 167 168 169 170 171 172 173
"\n"
"encoding is the name of the encoding used to decode or encode the\n"
"file. This should only be used in text mode. The default encoding is\n"
"platform dependent, but any encoding supported by Python can be\n"
"passed.  See the codecs module for the list of supported encodings.\n"
"\n"
"errors is an optional string that specifies how encoding errors are to\n"
"be handled---this argument should not be used in binary mode. Pass\n"
"'strict' to raise a ValueError exception if there is an encoding error\n"
"(the default of None has the same effect), or pass 'ignore' to ignore\n"
"errors. (Note that ignoring encoding errors can lead to data loss.)\n"
174 175
"See the documentation for codecs.register or run 'help(codecs.Codec)'\n"
"for a list of the permitted encoding error strings.\n"
176 177 178 179 180 181 182 183 184 185 186 187 188 189 190
"\n"
"newline controls how universal newlines works (it only applies to text\n"
"mode). It can be None, '', '\\n', '\\r', and '\\r\\n'.  It works as\n"
"follows:\n"
"\n"
"* On input, if newline is None, universal newlines mode is\n"
"  enabled. Lines in the input can end in '\\n', '\\r', or '\\r\\n', and\n"
"  these are translated into '\\n' before being returned to the\n"
"  caller. If it is '', universal newline mode is enabled, but line\n"
"  endings are returned to the caller untranslated. If it has any of\n"
"  the other legal values, input lines are only terminated by the given\n"
"  string, and the line ending is returned to the caller untranslated.\n"
"\n"
"* On output, if newline is None, any '\\n' characters written are\n"
"  translated to the system default line separator, os.linesep. If\n"
191
"  newline is '' or '\\n', no translation takes place. If newline is any\n"
192 193
"  of the other legal values, any '\\n' characters written are translated\n"
"  to the given string.\n"
194 195 196 197 198
"\n"
"If closefd is False, the underlying file descriptor will be kept open\n"
"when the file is closed. This does not work when a file name is given\n"
"and must be True in that case.\n"
"\n"
199 200 201 202 203 204
"A custom opener can be used by passing a callable as *opener*. The\n"
"underlying file descriptor for the file object is then obtained by\n"
"calling *opener* with (*file*, *flags*). *opener* must return an open\n"
"file descriptor (passing os.open as *opener* results in functionality\n"
"similar to passing None).\n"
"\n"
205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224
"open() returns a file object whose type depends on the mode, and\n"
"through which the standard file operations such as reading and writing\n"
"are performed. When open() is used to open a file in a text mode ('w',\n"
"'r', 'wt', 'rt', etc.), it returns a TextIOWrapper. When used to open\n"
"a file in a binary mode, the returned class varies: in read binary\n"
"mode, it returns a BufferedReader; in write binary and append binary\n"
"modes, it returns a BufferedWriter, and in read/write mode, it returns\n"
"a BufferedRandom.\n"
"\n"
"It is also possible to use a string or bytearray as a file for both\n"
"reading and writing. For strings StringIO can be used like a file\n"
"opened in a text mode, and for bytes a BytesIO can be used like a file\n"
"opened in a binary mode.\n"
    );

static PyObject *
io_open(PyObject *self, PyObject *args, PyObject *kwds)
{
    char *kwlist[] = {"file", "mode", "buffering",
                      "encoding", "errors", "newline",
225 226
                      "closefd", "opener", NULL};
    PyObject *file, *opener = Py_None;
227 228 229 230 231
    char *mode = "r";
    int buffering = -1, closefd = 1;
    char *encoding = NULL, *errors = NULL, *newline = NULL;
    unsigned i;

232
    int creating = 0, reading = 0, writing = 0, appending = 0, updating = 0;
233 234
    int text = 0, binary = 0, universal = 0;

235
    char rawmode[6], *m;
236 237
    int line_buffering, isatty;

238
    PyObject *raw, *modeobj = NULL, *buffer, *wrapper, *result = NULL;
239

240 241
    _Py_IDENTIFIER(isatty);
    _Py_IDENTIFIER(fileno);
242
    _Py_IDENTIFIER(mode);
243
    _Py_IDENTIFIER(close);
244

245
    if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|sizzziO:open", kwlist,
246 247
                                     &file, &mode, &buffering,
                                     &encoding, &errors, &newline,
248
                                     &closefd, &opener)) {
249 250 251 252 253 254 255 256 257 258 259 260 261 262 263
        return NULL;
    }

    if (!PyUnicode_Check(file) &&
	!PyBytes_Check(file) &&
	!PyNumber_Check(file)) {
        PyErr_Format(PyExc_TypeError, "invalid file: %R", file);
        return NULL;
    }

    /* Decode mode */
    for (i = 0; i < strlen(mode); i++) {
        char c = mode[i];

        switch (c) {
264 265 266
        case 'x':
            creating = 1;
            break;
267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302
        case 'r':
            reading = 1;
            break;
        case 'w':
            writing = 1;
            break;
        case 'a':
            appending = 1;
            break;
        case '+':
            updating = 1;
            break;
        case 't':
            text = 1;
            break;
        case 'b':
            binary = 1;
            break;
        case 'U':
            universal = 1;
            reading = 1;
            break;
        default:
            goto invalid_mode;
        }

        /* c must not be duplicated */
        if (strchr(mode+i+1, c)) {
          invalid_mode:
            PyErr_Format(PyExc_ValueError, "invalid mode: '%s'", mode);
            return NULL;
        }

    }

    m = rawmode;
303
    if (creating)  *(m++) = 'x';
304 305 306 307 308 309 310 311 312 313 314 315 316
    if (reading)   *(m++) = 'r';
    if (writing)   *(m++) = 'w';
    if (appending) *(m++) = 'a';
    if (updating)  *(m++) = '+';
    *m = '\0';

    /* Parameters validation */
    if (universal) {
        if (writing || appending) {
            PyErr_SetString(PyExc_ValueError,
                            "can't use U and writing mode at once");
            return NULL;
        }
317 318 319
        if (PyErr_WarnEx(PyExc_DeprecationWarning,
                         "'U' mode is deprecated", 1) < 0)
            return NULL;
320 321 322 323 324 325 326 327 328
        reading = 1;
    }

    if (text && binary) {
        PyErr_SetString(PyExc_ValueError,
                        "can't have text and binary mode at once");
        return NULL;
    }

329
    if (creating + reading + writing + appending > 1) {
330
        PyErr_SetString(PyExc_ValueError,
331
                        "must have exactly one of create/read/write/append mode");
332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354
        return NULL;
    }

    if (binary && encoding != NULL) {
        PyErr_SetString(PyExc_ValueError,
                        "binary mode doesn't take an encoding argument");
        return NULL;
    }

    if (binary && errors != NULL) {
        PyErr_SetString(PyExc_ValueError,
                        "binary mode doesn't take an errors argument");
        return NULL;
    }

    if (binary && newline != NULL) {
        PyErr_SetString(PyExc_ValueError,
                        "binary mode doesn't take a newline argument");
        return NULL;
    }

    /* Create the Raw file stream */
    raw = PyObject_CallFunction((PyObject *)&PyFileIO_Type,
355
                                "OsiO", file, rawmode, closefd, opener);
356 357
    if (raw == NULL)
        return NULL;
358
    result = raw;
359 360 361 362 363 364 365

    modeobj = PyUnicode_FromString(mode);
    if (modeobj == NULL)
        goto error;

    /* buffering */
    {
366
        PyObject *res = _PyObject_CallMethodId(raw, &PyId_isatty, NULL);
367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387
        if (res == NULL)
            goto error;
        isatty = PyLong_AsLong(res);
        Py_DECREF(res);
        if (isatty == -1 && PyErr_Occurred())
            goto error;
    }

    if (buffering == 1 || (buffering < 0 && isatty)) {
        buffering = -1;
        line_buffering = 1;
    }
    else
        line_buffering = 0;

    if (buffering < 0) {
        buffering = DEFAULT_BUFFER_SIZE;
#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
        {
            struct stat st;
            long fileno;
388
            PyObject *res = _PyObject_CallMethodId(raw, &PyId_fileno, NULL);
389 390 391 392 393 394 395 396
            if (res == NULL)
                goto error;

            fileno = PyLong_AsLong(res);
            Py_DECREF(res);
            if (fileno == -1 && PyErr_Occurred())
                goto error;

397
            if (fstat(fileno, &st) >= 0 && st.st_blksize > 1)
398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416
                buffering = st.st_blksize;
        }
#endif
    }
    if (buffering < 0) {
        PyErr_SetString(PyExc_ValueError,
                        "invalid buffering size");
        goto error;
    }

    /* if not buffering, returns the raw file object */
    if (buffering == 0) {
        if (!binary) {
            PyErr_SetString(PyExc_ValueError,
                            "can't have unbuffered text I/O");
            goto error;
        }

        Py_DECREF(modeobj);
417
        return result;
418 419 420 421 422 423 424 425
    }

    /* wraps into a buffered file */
    {
        PyObject *Buffered_class;

        if (updating)
            Buffered_class = (PyObject *)&PyBufferedRandom_Type;
426
        else if (creating || writing || appending)
427 428 429 430 431 432 433 434 435 436 437 438 439
            Buffered_class = (PyObject *)&PyBufferedWriter_Type;
        else if (reading)
            Buffered_class = (PyObject *)&PyBufferedReader_Type;
        else {
            PyErr_Format(PyExc_ValueError,
                         "unknown mode: '%s'", mode);
            goto error;
        }

        buffer = PyObject_CallFunction(Buffered_class, "Oi", raw, buffering);
    }
    if (buffer == NULL)
        goto error;
440 441
    result = buffer;
    Py_DECREF(raw);
442 443 444 445 446


    /* if binary, returns the buffered file */
    if (binary) {
        Py_DECREF(modeobj);
447
        return result;
448 449 450 451 452 453 454 455 456 457
    }

    /* wraps into a TextIOWrapper */
    wrapper = PyObject_CallFunction((PyObject *)&PyTextIOWrapper_Type,
				    "Osssi",
				    buffer,
				    encoding, errors, newline,
				    line_buffering);
    if (wrapper == NULL)
        goto error;
458 459
    result = wrapper;
    Py_DECREF(buffer);
460

461
    if (_PyObject_SetAttrId(wrapper, &PyId_mode, modeobj) < 0)
462 463
        goto error;
    Py_DECREF(modeobj);
464
    return result;
465 466

  error:
467 468 469 470 471 472
    if (result != NULL) {
        PyObject *exc, *val, *tb;
        PyErr_Fetch(&exc, &val, &tb);
        if (_PyObject_CallMethodId(result, &PyId_close, NULL) != NULL)
            PyErr_Restore(exc, val, tb);
        else {
473 474
            PyObject *exc2, *val2, *tb2;
            PyErr_Fetch(&exc2, &val2, &tb2);
475 476 477
            PyErr_NormalizeException(&exc, &val, &tb);
            Py_XDECREF(exc);
            Py_XDECREF(tb);
478
            PyErr_NormalizeException(&exc2, &val2, &tb2);
479
            PyException_SetContext(val2, val);
480
            PyErr_Restore(exc2, val2, tb2);
481 482 483
        }
        Py_DECREF(result);
    }
484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535
    Py_XDECREF(modeobj);
    return NULL;
}

/*
 * Private helpers for the io module.
 */

Py_off_t
PyNumber_AsOff_t(PyObject *item, PyObject *err)
{
    Py_off_t result;
    PyObject *runerr;
    PyObject *value = PyNumber_Index(item);
    if (value == NULL)
        return -1;

    /* We're done if PyLong_AsSsize_t() returns without error. */
    result = PyLong_AsOff_t(value);
    if (result != -1 || !(runerr = PyErr_Occurred()))
        goto finish;

    /* Error handling code -- only manage OverflowError differently */
    if (!PyErr_GivenExceptionMatches(runerr, PyExc_OverflowError))
        goto finish;

    PyErr_Clear();
    /* If no error-handling desired then the default clipping
       is sufficient.
     */
    if (!err) {
        assert(PyLong_Check(value));
        /* Whether or not it is less than or equal to
           zero is determined by the sign of ob_size
        */
        if (_PyLong_Sign(value) < 0)
            result = PY_OFF_T_MIN;
        else
            result = PY_OFF_T_MAX;
    }
    else {
        /* Otherwise replace the error with caller's error object. */
        PyErr_Format(err,
                     "cannot fit '%.200s' into an offset-sized integer",
                     item->ob_type->tp_name);
    }

 finish:
    Py_DECREF(value);
    return result;
}

536 537

/* Basically the "n" format code with the ability to turn None into -1. */
538
int
539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559
_PyIO_ConvertSsize_t(PyObject *obj, void *result) {
    Py_ssize_t limit;
    if (obj == Py_None) {
        limit = -1;
    }
    else if (PyNumber_Check(obj)) {
        limit = PyNumber_AsSsize_t(obj, PyExc_OverflowError);
        if (limit == -1 && PyErr_Occurred())
            return 0;
    }
    else {
        PyErr_Format(PyExc_TypeError,
                     "integer argument expected, got '%.200s'",
                     Py_TYPE(obj)->tp_name);
        return 0;
    }
    *((Py_ssize_t *)result) = limit;
    return 1;
}


560 561 562 563 564 565 566 567 568 569 570 571 572 573
_PyIO_State *
_PyIO_get_module_state(void)
{
    PyObject *mod = PyState_FindModule(&_PyIO_Module);
    _PyIO_State *state;
    if (mod == NULL || (state = IO_MOD_STATE(mod)) == NULL) {
        PyErr_SetString(PyExc_RuntimeError,
                        "could not find io module state "
                        "(interpreter shutdown?)");
        return NULL;
    }
    return state;
}

574 575 576 577 578 579 580 581 582 583 584 585 586
PyObject *
_PyIO_get_locale_module(_PyIO_State *state)
{
    PyObject *mod;
    if (state->locale_module != NULL) {
        assert(PyWeakref_CheckRef(state->locale_module));
        mod = PyWeakref_GET_OBJECT(state->locale_module);
        if (mod != Py_None) {
            Py_INCREF(mod);
            return mod;
        }
        Py_CLEAR(state->locale_module);
    }
587
    mod = PyImport_ImportModule("_bootlocale");
588 589 590 591 592 593 594 595 596 597 598
    if (mod == NULL)
        return NULL;
    state->locale_module = PyWeakref_NewRef(mod, NULL);
    if (state->locale_module == NULL) {
        Py_DECREF(mod);
        return NULL;
    }
    return mod;
}


599 600 601 602 603 604 605 606 607 608 609 610
static int
iomodule_traverse(PyObject *mod, visitproc visit, void *arg) {
    _PyIO_State *state = IO_MOD_STATE(mod);
    if (!state->initialized)
        return 0;
    if (state->locale_module != NULL) {
        Py_VISIT(state->locale_module);
    }
    Py_VISIT(state->unsupported_operation);
    return 0;
}

611

612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627
static int
iomodule_clear(PyObject *mod) {
    _PyIO_State *state = IO_MOD_STATE(mod);
    if (!state->initialized)
        return 0;
    if (state->locale_module != NULL)
        Py_CLEAR(state->locale_module);
    Py_CLEAR(state->unsupported_operation);
    return 0;
}

static void
iomodule_free(PyObject *mod) {
    iomodule_clear(mod);
}

628

629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683
/*
 * Module definition
 */

static PyMethodDef module_methods[] = {
    {"open", (PyCFunction)io_open, METH_VARARGS|METH_KEYWORDS, open_doc},
    {NULL, NULL}
};

struct PyModuleDef _PyIO_Module = {
    PyModuleDef_HEAD_INIT,
    "io",
    module_doc,
    sizeof(_PyIO_State),
    module_methods,
    NULL,
    iomodule_traverse,
    iomodule_clear,
    (freefunc)iomodule_free,
};

PyMODINIT_FUNC
PyInit__io(void)
{
    PyObject *m = PyModule_Create(&_PyIO_Module);
    _PyIO_State *state = NULL;
    if (m == NULL)
        return NULL;
    state = IO_MOD_STATE(m);
    state->initialized = 0;

#define ADD_TYPE(type, name) \
    if (PyType_Ready(type) < 0) \
        goto fail; \
    Py_INCREF(type); \
    if (PyModule_AddObject(m, name, (PyObject *)type) < 0) {  \
        Py_DECREF(type); \
        goto fail; \
    }

    /* DEFAULT_BUFFER_SIZE */
    if (PyModule_AddIntMacro(m, DEFAULT_BUFFER_SIZE) < 0)
        goto fail;

    /* UnsupportedOperation inherits from ValueError and IOError */
    state->unsupported_operation = PyObject_CallFunction(
        (PyObject *)&PyType_Type, "s(OO){}",
        "UnsupportedOperation", PyExc_ValueError, PyExc_IOError);
    if (state->unsupported_operation == NULL)
        goto fail;
    Py_INCREF(state->unsupported_operation);
    if (PyModule_AddObject(m, "UnsupportedOperation",
                           state->unsupported_operation) < 0)
        goto fail;

684 685 686 687 688
    /* BlockingIOError, for compatibility */
    Py_INCREF(PyExc_BlockingIOError);
    if (PyModule_AddObject(m, "BlockingIOError",
                           (PyObject *) PyExc_BlockingIOError) < 0)
        goto fail;
689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705

    /* Concrete base types of the IO ABCs.
       (the ABCs themselves are declared through inheritance in io.py)
    */
    ADD_TYPE(&PyIOBase_Type, "_IOBase");
    ADD_TYPE(&PyRawIOBase_Type, "_RawIOBase");
    ADD_TYPE(&PyBufferedIOBase_Type, "_BufferedIOBase");
    ADD_TYPE(&PyTextIOBase_Type, "_TextIOBase");

    /* Implementation of concrete IO objects. */
    /* FileIO */
    PyFileIO_Type.tp_base = &PyRawIOBase_Type;
    ADD_TYPE(&PyFileIO_Type, "FileIO");

    /* BytesIO */
    PyBytesIO_Type.tp_base = &PyBufferedIOBase_Type;
    ADD_TYPE(&PyBytesIO_Type, "BytesIO");
706 707
    if (PyType_Ready(&_PyBytesIOBuffer_Type) < 0)
        goto fail;
708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736

    /* StringIO */
    PyStringIO_Type.tp_base = &PyTextIOBase_Type;
    ADD_TYPE(&PyStringIO_Type, "StringIO");

    /* BufferedReader */
    PyBufferedReader_Type.tp_base = &PyBufferedIOBase_Type;
    ADD_TYPE(&PyBufferedReader_Type, "BufferedReader");

    /* BufferedWriter */
    PyBufferedWriter_Type.tp_base = &PyBufferedIOBase_Type;
    ADD_TYPE(&PyBufferedWriter_Type, "BufferedWriter");

    /* BufferedRWPair */
    PyBufferedRWPair_Type.tp_base = &PyBufferedIOBase_Type;
    ADD_TYPE(&PyBufferedRWPair_Type, "BufferedRWPair");

    /* BufferedRandom */
    PyBufferedRandom_Type.tp_base = &PyBufferedIOBase_Type;
    ADD_TYPE(&PyBufferedRandom_Type, "BufferedRandom");

    /* TextIOWrapper */
    PyTextIOWrapper_Type.tp_base = &PyTextIOBase_Type;
    ADD_TYPE(&PyTextIOWrapper_Type, "TextIOWrapper");

    /* IncrementalNewlineDecoder */
    ADD_TYPE(&PyIncrementalNewlineDecoder_Type, "IncrementalNewlineDecoder");

    /* Interned strings */
737 738 739
#define ADD_INTERNED(name) \
    if (!_PyIO_str_ ## name && \
        !(_PyIO_str_ ## name = PyUnicode_InternFromString(# name))) \
740
        goto fail;
741 742 743 744 745 746 747 748 749 750 751 752 753

    ADD_INTERNED(close)
    ADD_INTERNED(closed)
    ADD_INTERNED(decode)
    ADD_INTERNED(encode)
    ADD_INTERNED(fileno)
    ADD_INTERNED(flush)
    ADD_INTERNED(getstate)
    ADD_INTERNED(isatty)
    ADD_INTERNED(newlines)
    ADD_INTERNED(read)
    ADD_INTERNED(read1)
    ADD_INTERNED(readable)
754
    ADD_INTERNED(readall)
755 756 757 758 759 760 761 762 763 764 765 766 767
    ADD_INTERNED(readinto)
    ADD_INTERNED(readline)
    ADD_INTERNED(reset)
    ADD_INTERNED(seek)
    ADD_INTERNED(seekable)
    ADD_INTERNED(setstate)
    ADD_INTERNED(tell)
    ADD_INTERNED(truncate)
    ADD_INTERNED(write)
    ADD_INTERNED(writable)

    if (!_PyIO_str_nl &&
        !(_PyIO_str_nl = PyUnicode_InternFromString("\n")))
768
        goto fail;
769 770 771

    if (!_PyIO_empty_str &&
        !(_PyIO_empty_str = PyUnicode_FromStringAndSize(NULL, 0)))
772
        goto fail;
773 774
    if (!_PyIO_empty_bytes &&
        !(_PyIO_empty_bytes = PyBytes_FromStringAndSize(NULL, 0)))
775
        goto fail;
776 777
    if (!_PyIO_zero &&
        !(_PyIO_zero = PyLong_FromLong(0L)))
778
        goto fail;
779 780 781 782 783 784 785 786 787 788

    state->initialized = 1;

    return m;

  fail:
    Py_XDECREF(state->unsupported_operation);
    Py_DECREF(m);
    return NULL;
}