Coverage Report

Created: 2026-05-16 06:46

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/cpython/Modules/_io/clinic/_iomodule.c.h
Line
Count
Source
1
/*[clinic input]
2
preserve
3
[clinic start generated code]*/
4
5
#if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE)
6
#  include "pycore_gc.h"          // PyGC_Head
7
#  include "pycore_runtime.h"     // _Py_ID()
8
#endif
9
#include "pycore_modsupport.h"    // _PyArg_UnpackKeywords()
10
11
PyDoc_STRVAR(_io_open__doc__,
12
"open($module, /, file, mode=\'r\', buffering=-1, encoding=None,\n"
13
"     errors=None, newline=None, closefd=True, opener=None)\n"
14
"--\n"
15
"\n"
16
"Open file and return a stream.  Raise OSError upon failure.\n"
17
"\n"
18
"file is either a text or byte string giving the name (and the path\n"
19
"if the file isn\'t in the current working directory) of the file to\n"
20
"be opened or an integer file descriptor of the file to be\n"
21
"wrapped. (If a file descriptor is given, it is closed when the\n"
22
"returned I/O object is closed, unless closefd is set to False.)\n"
23
"\n"
24
"mode is an optional string that specifies the mode in which the file\n"
25
"is opened. It defaults to \'r\' which means open for reading in text\n"
26
"mode.  Other common values are \'w\' for writing (truncating the file if\n"
27
"it already exists), \'x\' for creating and writing to a new file, and\n"
28
"\'a\' for appending (which on some Unix systems, means that all writes\n"
29
"append to the end of the file regardless of the current seek position).\n"
30
"In text mode, if encoding is not specified the encoding used is platform\n"
31
"dependent: locale.getencoding() is called to get the current locale encoding.\n"
32
"(For reading and writing raw bytes use binary mode and leave encoding\n"
33
"unspecified.) The available modes are:\n"
34
"\n"
35
"========= ===============================================================\n"
36
"Character Meaning\n"
37
"--------- ---------------------------------------------------------------\n"
38
"\'r\'       open for reading (default)\n"
39
"\'w\'       open for writing, truncating the file first\n"
40
"\'x\'       create a new file and open it for writing\n"
41
"\'a\'       open for writing, appending to the end of the file if it exists\n"
42
"\'b\'       binary mode\n"
43
"\'t\'       text mode (default)\n"
44
"\'+\'       open a disk file for updating (reading and writing)\n"
45
"========= ===============================================================\n"
46
"\n"
47
"The default mode is \'rt\' (open for reading text). For binary random\n"
48
"access, the mode \'w+b\' opens and truncates the file to 0 bytes, while\n"
49
"\'r+b\' opens the file without truncation. The \'x\' mode implies \'w\' and\n"
50
"raises an `FileExistsError` if the file already exists.\n"
51
"\n"
52
"Python distinguishes between files opened in binary and text modes,\n"
53
"even when the underlying operating system doesn\'t. Files opened in\n"
54
"binary mode (appending \'b\' to the mode argument) return contents as\n"
55
"bytes objects without any decoding. In text mode (the default, or when\n"
56
"\'t\' is appended to the mode argument), the contents of the file are\n"
57
"returned as strings, the bytes having been first decoded using a\n"
58
"platform-dependent encoding or using the specified encoding if given.\n"
59
"\n"
60
"buffering is an optional integer used to set the buffering policy.\n"
61
"Pass 0 to switch buffering off (only allowed in binary mode), 1 to select\n"
62
"line buffering (only usable in text mode), and an integer > 1 to indicate\n"
63
"the size of a fixed-size chunk buffer.  When no buffering argument is\n"
64
"given, the default buffering policy works as follows:\n"
65
"\n"
66
"* Binary files are buffered in fixed-size chunks; the size of the buffer\n"
67
" is max(min(blocksize, 8 MiB), DEFAULT_BUFFER_SIZE)\n"
68
" when the device block size is available.\n"
69
" On most systems, the buffer will typically be 128 kilobytes long.\n"
70
"\n"
71
"* \"Interactive\" text files (files for which isatty() returns True)\n"
72
"  use line buffering.  Other text files use the policy described above\n"
73
"  for binary files.\n"
74
"\n"
75
"encoding is the name of the encoding used to decode or encode the\n"
76
"file. This should only be used in text mode. The default encoding is\n"
77
"platform dependent, but any encoding supported by Python can be\n"
78
"passed.  See the codecs module for the list of supported encodings.\n"
79
"\n"
80
"errors is an optional string that specifies how encoding errors are to\n"
81
"be handled---this argument should not be used in binary mode. Pass\n"
82
"\'strict\' to raise a ValueError exception if there is an encoding error\n"
83
"(the default of None has the same effect), or pass \'ignore\' to ignore\n"
84
"errors. (Note that ignoring encoding errors can lead to data loss.)\n"
85
"See the documentation for codecs.register or run \'help(codecs.Codec)\'\n"
86
"for a list of the permitted encoding error strings.\n"
87
"\n"
88
"newline controls how universal newlines works (it only applies to text\n"
89
"mode). It can be None, \'\', \'\\n\', \'\\r\', and \'\\r\\n\'.  It works as\n"
90
"follows:\n"
91
"\n"
92
"* On input, if newline is None, universal newlines mode is\n"
93
"  enabled. Lines in the input can end in \'\\n\', \'\\r\', or \'\\r\\n\', and\n"
94
"  these are translated into \'\\n\' before being returned to the\n"
95
"  caller. If it is \'\', universal newline mode is enabled, but line\n"
96
"  endings are returned to the caller untranslated. If it has any of\n"
97
"  the other legal values, input lines are only terminated by the given\n"
98
"  string, and the line ending is returned to the caller untranslated.\n"
99
"\n"
100
"* On output, if newline is None, any \'\\n\' characters written are\n"
101
"  translated to the system default line separator, os.linesep. If\n"
102
"  newline is \'\' or \'\\n\', no translation takes place. If newline is any\n"
103
"  of the other legal values, any \'\\n\' characters written are translated\n"
104
"  to the given string.\n"
105
"\n"
106
"If closefd is False, the underlying file descriptor will be kept open\n"
107
"when the file is closed. This does not work when a file name is given\n"
108
"and must be True in that case.\n"
109
"\n"
110
"A custom opener can be used by passing a callable as *opener*. The\n"
111
"underlying file descriptor for the file object is then obtained by\n"
112
"calling *opener* with (*file*, *flags*). *opener* must return an open\n"
113
"file descriptor (passing os.open as *opener* results in functionality\n"
114
"similar to passing None).\n"
115
"\n"
116
"open() returns a file object whose type depends on the mode, and\n"
117
"through which the standard file operations such as reading and writing\n"
118
"are performed. When open() is used to open a file in a text mode (\'w\',\n"
119
"\'r\', \'wt\', \'rt\', etc.), it returns a TextIOWrapper. When used to open\n"
120
"a file in a binary mode, the returned class varies: in read binary\n"
121
"mode, it returns a BufferedReader; in write binary and append binary\n"
122
"modes, it returns a BufferedWriter, and in read/write mode, it returns\n"
123
"a BufferedRandom.\n"
124
"\n"
125
"It is also possible to use a string or bytearray as a file for both\n"
126
"reading and writing. For strings StringIO can be used like a file\n"
127
"opened in a text mode, and for bytes a BytesIO can be used like a file\n"
128
"opened in a binary mode.");
129
130
#define _IO_OPEN_METHODDEF    \
131
    {"open", _PyCFunction_CAST(_io_open), METH_FASTCALL|METH_KEYWORDS, _io_open__doc__},
132
133
static PyObject *
134
_io_open_impl(PyObject *module, PyObject *file, const char *mode,
135
              int buffering, const char *encoding, const char *errors,
136
              const char *newline, int closefd, PyObject *opener);
137
138
static PyObject *
139
_io_open(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
140
29.7k
{
141
29.7k
    PyObject *return_value = NULL;
142
29.7k
    #if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE)
143
144
29.7k
    #define NUM_KEYWORDS 8
145
29.7k
    static struct {
146
29.7k
        PyGC_Head _this_is_not_used;
147
29.7k
        PyObject_VAR_HEAD
148
29.7k
        Py_hash_t ob_hash;
149
29.7k
        PyObject *ob_item[NUM_KEYWORDS];
150
29.7k
    } _kwtuple = {
151
29.7k
        .ob_base = PyVarObject_HEAD_INIT(&PyTuple_Type, NUM_KEYWORDS)
152
29.7k
        .ob_hash = -1,
153
29.7k
        .ob_item = { &_Py_ID(file), &_Py_ID(mode), &_Py_ID(buffering), &_Py_ID(encoding), &_Py_ID(errors), &_Py_ID(newline), &_Py_ID(closefd), &_Py_ID(opener), },
154
29.7k
    };
155
29.7k
    #undef NUM_KEYWORDS
156
29.7k
    #define KWTUPLE (&_kwtuple.ob_base.ob_base)
157
158
    #else  // !Py_BUILD_CORE
159
    #  define KWTUPLE NULL
160
    #endif  // !Py_BUILD_CORE
161
162
29.7k
    static const char * const _keywords[] = {"file", "mode", "buffering", "encoding", "errors", "newline", "closefd", "opener", NULL};
163
29.7k
    static _PyArg_Parser _parser = {
164
29.7k
        .keywords = _keywords,
165
29.7k
        .fname = "open",
166
29.7k
        .kwtuple = KWTUPLE,
167
29.7k
    };
168
29.7k
    #undef KWTUPLE
169
29.7k
    PyObject *argsbuf[8];
170
29.7k
    Py_ssize_t noptargs = nargs + (kwnames ? PyTuple_GET_SIZE(kwnames) : 0) - 1;
171
29.7k
    PyObject *file;
172
29.7k
    const char *mode = "r";
173
29.7k
    int buffering = -1;
174
29.7k
    const char *encoding = NULL;
175
29.7k
    const char *errors = NULL;
176
29.7k
    const char *newline = NULL;
177
29.7k
    int closefd = 1;
178
29.7k
    PyObject *opener = Py_None;
179
180
29.7k
    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser,
181
29.7k
            /*minpos*/ 1, /*maxpos*/ 8, /*minkw*/ 0, /*varpos*/ 0, argsbuf);
182
29.7k
    if (!args) {
183
0
        goto exit;
184
0
    }
185
29.7k
    file = args[0];
186
29.7k
    if (!noptargs) {
187
0
        goto skip_optional_pos;
188
0
    }
189
29.7k
    if (args[1]) {
190
29.7k
        if (!PyUnicode_Check(args[1])) {
191
0
            _PyArg_BadArgument("open", "argument 'mode'", "str", args[1]);
192
0
            goto exit;
193
0
        }
194
29.7k
        Py_ssize_t mode_length;
195
29.7k
        mode = PyUnicode_AsUTF8AndSize(args[1], &mode_length);
196
29.7k
        if (mode == NULL) {
197
0
            goto exit;
198
0
        }
199
29.7k
        if (strlen(mode) != (size_t)mode_length) {
200
0
            PyErr_SetString(PyExc_ValueError, "embedded null character");
201
0
            goto exit;
202
0
        }
203
29.7k
        if (!--noptargs) {
204
29.6k
            goto skip_optional_pos;
205
29.6k
        }
206
29.7k
    }
207
124
    if (args[2]) {
208
124
        buffering = PyLong_AsInt(args[2]);
209
124
        if (buffering == -1 && PyErr_Occurred()) {
210
0
            goto exit;
211
0
        }
212
124
        if (!--noptargs) {
213
0
            goto skip_optional_pos;
214
0
        }
215
124
    }
216
124
    if (args[3]) {
217
124
        if (args[3] == Py_None) {
218
111
            encoding = NULL;
219
111
        }
220
13
        else if (PyUnicode_Check(args[3])) {
221
13
            Py_ssize_t encoding_length;
222
13
            encoding = PyUnicode_AsUTF8AndSize(args[3], &encoding_length);
223
13
            if (encoding == NULL) {
224
0
                goto exit;
225
0
            }
226
13
            if (strlen(encoding) != (size_t)encoding_length) {
227
0
                PyErr_SetString(PyExc_ValueError, "embedded null character");
228
0
                goto exit;
229
0
            }
230
13
        }
231
0
        else {
232
0
            _PyArg_BadArgument("open", "argument 'encoding'", "str or None", args[3]);
233
0
            goto exit;
234
0
        }
235
124
        if (!--noptargs) {
236
0
            goto skip_optional_pos;
237
0
        }
238
124
    }
239
124
    if (args[4]) {
240
124
        if (args[4] == Py_None) {
241
124
            errors = NULL;
242
124
        }
243
0
        else if (PyUnicode_Check(args[4])) {
244
0
            Py_ssize_t errors_length;
245
0
            errors = PyUnicode_AsUTF8AndSize(args[4], &errors_length);
246
0
            if (errors == NULL) {
247
0
                goto exit;
248
0
            }
249
0
            if (strlen(errors) != (size_t)errors_length) {
250
0
                PyErr_SetString(PyExc_ValueError, "embedded null character");
251
0
                goto exit;
252
0
            }
253
0
        }
254
0
        else {
255
0
            _PyArg_BadArgument("open", "argument 'errors'", "str or None", args[4]);
256
0
            goto exit;
257
0
        }
258
124
        if (!--noptargs) {
259
0
            goto skip_optional_pos;
260
0
        }
261
124
    }
262
124
    if (args[5]) {
263
124
        if (args[5] == Py_None) {
264
124
            newline = NULL;
265
124
        }
266
0
        else if (PyUnicode_Check(args[5])) {
267
0
            Py_ssize_t newline_length;
268
0
            newline = PyUnicode_AsUTF8AndSize(args[5], &newline_length);
269
0
            if (newline == NULL) {
270
0
                goto exit;
271
0
            }
272
0
            if (strlen(newline) != (size_t)newline_length) {
273
0
                PyErr_SetString(PyExc_ValueError, "embedded null character");
274
0
                goto exit;
275
0
            }
276
0
        }
277
0
        else {
278
0
            _PyArg_BadArgument("open", "argument 'newline'", "str or None", args[5]);
279
0
            goto exit;
280
0
        }
281
124
        if (!--noptargs) {
282
13
            goto skip_optional_pos;
283
13
        }
284
124
    }
285
111
    if (args[6]) {
286
111
        closefd = PyObject_IsTrue(args[6]);
287
111
        if (closefd < 0) {
288
0
            goto exit;
289
0
        }
290
111
        if (!--noptargs) {
291
111
            goto skip_optional_pos;
292
111
        }
293
111
    }
294
0
    opener = args[7];
295
29.7k
skip_optional_pos:
296
29.7k
    return_value = _io_open_impl(module, file, mode, buffering, encoding, errors, newline, closefd, opener);
297
298
29.7k
exit:
299
29.7k
    return return_value;
300
29.7k
}
301
302
PyDoc_STRVAR(_io_text_encoding__doc__,
303
"text_encoding($module, encoding, stacklevel=2, /)\n"
304
"--\n"
305
"\n"
306
"A helper function to choose the text encoding.\n"
307
"\n"
308
"When encoding is not None, this function returns it.\n"
309
"Otherwise, this function returns the default text encoding\n"
310
"(i.e. \"locale\" or \"utf-8\" depends on UTF-8 mode).\n"
311
"\n"
312
"This function emits an EncodingWarning if encoding is None and\n"
313
"sys.flags.warn_default_encoding is true.\n"
314
"\n"
315
"This can be used in APIs with an encoding=None parameter.\n"
316
"However, please consider using encoding=\"utf-8\" for new APIs.");
317
318
#define _IO_TEXT_ENCODING_METHODDEF    \
319
    {"text_encoding", _PyCFunction_CAST(_io_text_encoding), METH_FASTCALL, _io_text_encoding__doc__},
320
321
static PyObject *
322
_io_text_encoding_impl(PyObject *module, PyObject *encoding, int stacklevel);
323
324
static PyObject *
325
_io_text_encoding(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
326
26
{
327
26
    PyObject *return_value = NULL;
328
26
    PyObject *encoding;
329
26
    int stacklevel = 2;
330
331
26
    if (!_PyArg_CheckPositional("text_encoding", nargs, 1, 2)) {
332
0
        goto exit;
333
0
    }
334
26
    encoding = args[0];
335
26
    if (nargs < 2) {
336
26
        goto skip_optional;
337
26
    }
338
0
    stacklevel = PyLong_AsInt(args[1]);
339
0
    if (stacklevel == -1 && PyErr_Occurred()) {
340
0
        goto exit;
341
0
    }
342
26
skip_optional:
343
26
    return_value = _io_text_encoding_impl(module, encoding, stacklevel);
344
345
26
exit:
346
26
    return return_value;
347
26
}
348
349
PyDoc_STRVAR(_io_open_code__doc__,
350
"open_code($module, /, path)\n"
351
"--\n"
352
"\n"
353
"Opens the provided file with the intent to import the contents.\n"
354
"\n"
355
"This may perform extra validation beyond open(), but is otherwise interchangeable\n"
356
"with calling open(path, \'rb\').");
357
358
#define _IO_OPEN_CODE_METHODDEF    \
359
    {"open_code", _PyCFunction_CAST(_io_open_code), METH_FASTCALL|METH_KEYWORDS, _io_open_code__doc__},
360
361
static PyObject *
362
_io_open_code_impl(PyObject *module, PyObject *path);
363
364
static PyObject *
365
_io_open_code(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
366
6.46k
{
367
6.46k
    PyObject *return_value = NULL;
368
6.46k
    #if defined(Py_BUILD_CORE) && !defined(Py_BUILD_CORE_MODULE)
369
370
6.46k
    #define NUM_KEYWORDS 1
371
6.46k
    static struct {
372
6.46k
        PyGC_Head _this_is_not_used;
373
6.46k
        PyObject_VAR_HEAD
374
6.46k
        Py_hash_t ob_hash;
375
6.46k
        PyObject *ob_item[NUM_KEYWORDS];
376
6.46k
    } _kwtuple = {
377
6.46k
        .ob_base = PyVarObject_HEAD_INIT(&PyTuple_Type, NUM_KEYWORDS)
378
6.46k
        .ob_hash = -1,
379
6.46k
        .ob_item = { &_Py_ID(path), },
380
6.46k
    };
381
6.46k
    #undef NUM_KEYWORDS
382
6.46k
    #define KWTUPLE (&_kwtuple.ob_base.ob_base)
383
384
    #else  // !Py_BUILD_CORE
385
    #  define KWTUPLE NULL
386
    #endif  // !Py_BUILD_CORE
387
388
6.46k
    static const char * const _keywords[] = {"path", NULL};
389
6.46k
    static _PyArg_Parser _parser = {
390
6.46k
        .keywords = _keywords,
391
6.46k
        .fname = "open_code",
392
6.46k
        .kwtuple = KWTUPLE,
393
6.46k
    };
394
6.46k
    #undef KWTUPLE
395
6.46k
    PyObject *argsbuf[1];
396
6.46k
    PyObject *path;
397
398
6.46k
    args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser,
399
6.46k
            /*minpos*/ 1, /*maxpos*/ 1, /*minkw*/ 0, /*varpos*/ 0, argsbuf);
400
6.46k
    if (!args) {
401
0
        goto exit;
402
0
    }
403
6.46k
    if (!PyUnicode_Check(args[0])) {
404
0
        _PyArg_BadArgument("open_code", "argument 'path'", "str", args[0]);
405
0
        goto exit;
406
0
    }
407
6.46k
    path = args[0];
408
6.46k
    return_value = _io_open_code_impl(module, path);
409
410
6.46k
exit:
411
6.46k
    return return_value;
412
6.46k
}
413
/*[clinic end generated code: output=7a8e032c0424bce2 input=a9049054013a1b77]*/