1 /*[clinic input]
2 preserve
3 [clinic start generated code]*/
4
5 PyDoc_STRVAR(_io_open__doc__,
6 "open($module, /, file, mode=\'r\', buffering=-1, encoding=None,\n"
7 " errors=None, newline=None, closefd=True, opener=None)\n"
8 "--\n"
9 "\n"
10 "Open file and return a stream. Raise OSError upon failure.\n"
11 "\n"
12 "file is either a text or byte string giving the name (and the path\n"
13 "if the file isn\'t in the current working directory) of the file to\n"
14 "be opened or an integer file descriptor of the file to be\n"
15 "wrapped. (If a file descriptor is given, it is closed when the\n"
16 "returned I/O object is closed, unless closefd is set to False.)\n"
17 "\n"
18 "mode is an optional string that specifies the mode in which the file\n"
19 "is opened. It defaults to \'r\' which means open for reading in text\n"
20 "mode. Other common values are \'w\' for writing (truncating the file if\n"
21 "it already exists), \'x\' for creating and writing to a new file, and\n"
22 "\'a\' for appending (which on some Unix systems, means that all writes\n"
23 "append to the end of the file regardless of the current seek position).\n"
24 "In text mode, if encoding is not specified the encoding used is platform\n"
25 "dependent: locale.getencoding() is called to get the current locale encoding.\n"
26 "(For reading and writing raw bytes use binary mode and leave encoding\n"
27 "unspecified.) The available modes are:\n"
28 "\n"
29 "========= ===============================================================\n"
30 "Character Meaning\n"
31 "--------- ---------------------------------------------------------------\n"
32 "\'r\' open for reading (default)\n"
33 "\'w\' open for writing, truncating the file first\n"
34 "\'x\' create a new file and open it for writing\n"
35 "\'a\' open for writing, appending to the end of the file if it exists\n"
36 "\'b\' binary mode\n"
37 "\'t\' text mode (default)\n"
38 "\'+\' open a disk file for updating (reading and writing)\n"
39 "========= ===============================================================\n"
40 "\n"
41 "The default mode is \'rt\' (open for reading text). For binary random\n"
42 "access, the mode \'w+b\' opens and truncates the file to 0 bytes, while\n"
43 "\'r+b\' opens the file without truncation. The \'x\' mode implies \'w\' and\n"
44 "raises an `FileExistsError` if the file already exists.\n"
45 "\n"
46 "Python distinguishes between files opened in binary and text modes,\n"
47 "even when the underlying operating system doesn\'t. Files opened in\n"
48 "binary mode (appending \'b\' to the mode argument) return contents as\n"
49 "bytes objects without any decoding. In text mode (the default, or when\n"
50 "\'t\' is appended to the mode argument), the contents of the file are\n"
51 "returned as strings, the bytes having been first decoded using a\n"
52 "platform-dependent encoding or using the specified encoding if given.\n"
53 "\n"
54 "buffering is an optional integer used to set the buffering policy.\n"
55 "Pass 0 to switch buffering off (only allowed in binary mode), 1 to select\n"
56 "line buffering (only usable in text mode), and an integer > 1 to indicate\n"
57 "the size of a fixed-size chunk buffer. When no buffering argument is\n"
58 "given, the default buffering policy works as follows:\n"
59 "\n"
60 "* Binary files are buffered in fixed-size chunks; the size of the buffer\n"
61 " is chosen using a heuristic trying to determine the underlying device\'s\n"
62 " \"block size\" and falling back on `io.DEFAULT_BUFFER_SIZE`.\n"
63 " On many systems, the buffer will typically be 4096 or 8192 bytes long.\n"
64 "\n"
65 "* \"Interactive\" text files (files for which isatty() returns True)\n"
66 " use line buffering. Other text files use the policy described above\n"
67 " for binary files.\n"
68 "\n"
69 "encoding is the name of the encoding used to decode or encode the\n"
70 "file. This should only be used in text mode. The default encoding is\n"
71 "platform dependent, but any encoding supported by Python can be\n"
72 "passed. See the codecs module for the list of supported encodings.\n"
73 "\n"
74 "errors is an optional string that specifies how encoding errors are to\n"
75 "be handled---this argument should not be used in binary mode. Pass\n"
76 "\'strict\' to raise a ValueError exception if there is an encoding error\n"
77 "(the default of None has the same effect), or pass \'ignore\' to ignore\n"
78 "errors. (Note that ignoring encoding errors can lead to data loss.)\n"
79 "See the documentation for codecs.register or run \'help(codecs.Codec)\'\n"
80 "for a list of the permitted encoding error strings.\n"
81 "\n"
82 "newline controls how universal newlines works (it only applies to text\n"
83 "mode). It can be None, \'\', \'\\n\', \'\\r\', and \'\\r\\n\'. It works as\n"
84 "follows:\n"
85 "\n"
86 "* On input, if newline is None, universal newlines mode is\n"
87 " enabled. Lines in the input can end in \'\\n\', \'\\r\', or \'\\r\\n\', and\n"
88 " these are translated into \'\\n\' before being returned to the\n"
89 " caller. If it is \'\', universal newline mode is enabled, but line\n"
90 " endings are returned to the caller untranslated. If it has any of\n"
91 " the other legal values, input lines are only terminated by the given\n"
92 " string, and the line ending is returned to the caller untranslated.\n"
93 "\n"
94 "* On output, if newline is None, any \'\\n\' characters written are\n"
95 " translated to the system default line separator, os.linesep. If\n"
96 " newline is \'\' or \'\\n\', no translation takes place. If newline is any\n"
97 " of the other legal values, any \'\\n\' characters written are translated\n"
98 " to the given string.\n"
99 "\n"
100 "If closefd is False, the underlying file descriptor will be kept open\n"
101 "when the file is closed. This does not work when a file name is given\n"
102 "and must be True in that case.\n"
103 "\n"
104 "A custom opener can be used by passing a callable as *opener*. The\n"
105 "underlying file descriptor for the file object is then obtained by\n"
106 "calling *opener* with (*file*, *flags*). *opener* must return an open\n"
107 "file descriptor (passing os.open as *opener* results in functionality\n"
108 "similar to passing None).\n"
109 "\n"
110 "open() returns a file object whose type depends on the mode, and\n"
111 "through which the standard file operations such as reading and writing\n"
112 "are performed. When open() is used to open a file in a text mode (\'w\',\n"
113 "\'r\', \'wt\', \'rt\', etc.), it returns a TextIOWrapper. When used to open\n"
114 "a file in a binary mode, the returned class varies: in read binary\n"
115 "mode, it returns a BufferedReader; in write binary and append binary\n"
116 "modes, it returns a BufferedWriter, and in read/write mode, it returns\n"
117 "a BufferedRandom.\n"
118 "\n"
119 "It is also possible to use a string or bytearray as a file for both\n"
120 "reading and writing. For strings StringIO can be used like a file\n"
121 "opened in a text mode, and for bytes a BytesIO can be used like a file\n"
122 "opened in a binary mode.");
123
124 #define _IO_OPEN_METHODDEF \
125 {"open", _PyCFunction_CAST(_io_open), METH_FASTCALL|METH_KEYWORDS, _io_open__doc__},
126
127 static PyObject *
128 _io_open_impl(PyObject *module, PyObject *file, const char *mode,
129 int buffering, const char *encoding, const char *errors,
130 const char *newline, int closefd, PyObject *opener);
131
132 static PyObject *
133 _io_open(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
134 {
135 PyObject *return_value = NULL;
136 static const char * const _keywords[] = {"file", "mode", "buffering", "encoding", "errors", "newline", "closefd", "opener", NULL};
137 static _PyArg_Parser _parser = {NULL, _keywords, "open", 0};
138 PyObject *argsbuf[8];
139 Py_ssize_t noptargs = nargs + (kwnames ? PyTuple_GET_SIZE(kwnames) : 0) - 1;
140 PyObject *file;
141 const char *mode = "r";
142 int buffering = -1;
143 const char *encoding = NULL;
144 const char *errors = NULL;
145 const char *newline = NULL;
146 int closefd = 1;
147 PyObject *opener = Py_None;
148
149 args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 1, 8, 0, argsbuf);
150 if (!args) {
151 goto exit;
152 }
153 file = args[0];
154 if (!noptargs) {
155 goto skip_optional_pos;
156 }
157 if (args[1]) {
158 if (!PyUnicode_Check(args[1])) {
159 _PyArg_BadArgument("open", "argument 'mode'", "str", args[1]);
160 goto exit;
161 }
162 Py_ssize_t mode_length;
163 mode = PyUnicode_AsUTF8AndSize(args[1], &mode_length);
164 if (mode == NULL) {
165 goto exit;
166 }
167 if (strlen(mode) != (size_t)mode_length) {
168 PyErr_SetString(PyExc_ValueError, "embedded null character");
169 goto exit;
170 }
171 if (!--noptargs) {
172 goto skip_optional_pos;
173 }
174 }
175 if (args[2]) {
176 buffering = _PyLong_AsInt(args[2]);
177 if (buffering == -1 && PyErr_Occurred()) {
178 goto exit;
179 }
180 if (!--noptargs) {
181 goto skip_optional_pos;
182 }
183 }
184 if (args[3]) {
185 if (args[3] == Py_None) {
186 encoding = NULL;
187 }
188 else if (PyUnicode_Check(args[3])) {
189 Py_ssize_t encoding_length;
190 encoding = PyUnicode_AsUTF8AndSize(args[3], &encoding_length);
191 if (encoding == NULL) {
192 goto exit;
193 }
194 if (strlen(encoding) != (size_t)encoding_length) {
195 PyErr_SetString(PyExc_ValueError, "embedded null character");
196 goto exit;
197 }
198 }
199 else {
200 _PyArg_BadArgument("open", "argument 'encoding'", "str or None", args[3]);
201 goto exit;
202 }
203 if (!--noptargs) {
204 goto skip_optional_pos;
205 }
206 }
207 if (args[4]) {
208 if (args[4] == Py_None) {
209 errors = NULL;
210 }
211 else if (PyUnicode_Check(args[4])) {
212 Py_ssize_t errors_length;
213 errors = PyUnicode_AsUTF8AndSize(args[4], &errors_length);
214 if (errors == NULL) {
215 goto exit;
216 }
217 if (strlen(errors) != (size_t)errors_length) {
218 PyErr_SetString(PyExc_ValueError, "embedded null character");
219 goto exit;
220 }
221 }
222 else {
223 _PyArg_BadArgument("open", "argument 'errors'", "str or None", args[4]);
224 goto exit;
225 }
226 if (!--noptargs) {
227 goto skip_optional_pos;
228 }
229 }
230 if (args[5]) {
231 if (args[5] == Py_None) {
232 newline = NULL;
233 }
234 else if (PyUnicode_Check(args[5])) {
235 Py_ssize_t newline_length;
236 newline = PyUnicode_AsUTF8AndSize(args[5], &newline_length);
237 if (newline == NULL) {
238 goto exit;
239 }
240 if (strlen(newline) != (size_t)newline_length) {
241 PyErr_SetString(PyExc_ValueError, "embedded null character");
242 goto exit;
243 }
244 }
245 else {
246 _PyArg_BadArgument("open", "argument 'newline'", "str or None", args[5]);
247 goto exit;
248 }
249 if (!--noptargs) {
250 goto skip_optional_pos;
251 }
252 }
253 if (args[6]) {
254 closefd = _PyLong_AsInt(args[6]);
255 if (closefd == -1 && PyErr_Occurred()) {
256 goto exit;
257 }
258 if (!--noptargs) {
259 goto skip_optional_pos;
260 }
261 }
262 opener = args[7];
263 skip_optional_pos:
264 return_value = _io_open_impl(module, file, mode, buffering, encoding, errors, newline, closefd, opener);
265
266 exit:
267 return return_value;
268 }
269
270 PyDoc_STRVAR(_io_text_encoding__doc__,
271 "text_encoding($module, encoding, stacklevel=2, /)\n"
272 "--\n"
273 "\n"
274 "A helper function to choose the text encoding.\n"
275 "\n"
276 "When encoding is not None, this function returns it.\n"
277 "Otherwise, this function returns the default text encoding\n"
278 "(i.e. \"locale\" or \"utf-8\" depends on UTF-8 mode).\n"
279 "\n"
280 "This function emits an EncodingWarning if encoding is None and\n"
281 "sys.flags.warn_default_encoding is true.\n"
282 "\n"
283 "This can be used in APIs with an encoding=None parameter.\n"
284 "However, please consider using encoding=\"utf-8\" for new APIs.");
285
286 #define _IO_TEXT_ENCODING_METHODDEF \
287 {"text_encoding", _PyCFunction_CAST(_io_text_encoding), METH_FASTCALL, _io_text_encoding__doc__},
288
289 static PyObject *
290 _io_text_encoding_impl(PyObject *module, PyObject *encoding, int stacklevel);
291
292 static PyObject *
293 _io_text_encoding(PyObject *module, PyObject *const *args, Py_ssize_t nargs)
294 {
295 PyObject *return_value = NULL;
296 PyObject *encoding;
297 int stacklevel = 2;
298
299 if (!_PyArg_CheckPositional("text_encoding", nargs, 1, 2)) {
300 goto exit;
301 }
302 encoding = args[0];
303 if (nargs < 2) {
304 goto skip_optional;
305 }
306 stacklevel = _PyLong_AsInt(args[1]);
307 if (stacklevel == -1 && PyErr_Occurred()) {
308 goto exit;
309 }
310 skip_optional:
311 return_value = _io_text_encoding_impl(module, encoding, stacklevel);
312
313 exit:
314 return return_value;
315 }
316
317 PyDoc_STRVAR(_io_open_code__doc__,
318 "open_code($module, /, path)\n"
319 "--\n"
320 "\n"
321 "Opens the provided file with the intent to import the contents.\n"
322 "\n"
323 "This may perform extra validation beyond open(), but is otherwise interchangeable\n"
324 "with calling open(path, \'rb\').");
325
326 #define _IO_OPEN_CODE_METHODDEF \
327 {"open_code", _PyCFunction_CAST(_io_open_code), METH_FASTCALL|METH_KEYWORDS, _io_open_code__doc__},
328
329 static PyObject *
330 _io_open_code_impl(PyObject *module, PyObject *path);
331
332 static PyObject *
333 _io_open_code(PyObject *module, PyObject *const *args, Py_ssize_t nargs, PyObject *kwnames)
334 {
335 PyObject *return_value = NULL;
336 static const char * const _keywords[] = {"path", NULL};
337 static _PyArg_Parser _parser = {NULL, _keywords, "open_code", 0};
338 PyObject *argsbuf[1];
339 PyObject *path;
340
341 args = _PyArg_UnpackKeywords(args, nargs, NULL, kwnames, &_parser, 1, 1, 0, argsbuf);
342 if (!args) {
343 goto exit;
344 }
345 if (!PyUnicode_Check(args[0])) {
346 _PyArg_BadArgument("open_code", "argument 'path'", "str", args[0]);
347 goto exit;
348 }
349 if (PyUnicode_READY(args[0]) == -1) {
350 goto exit;
351 }
352 path = args[0];
353 return_value = _io_open_code_impl(module, path);
354
355 exit:
356 return return_value;
357 }
358 /*[clinic end generated code: output=c4d7e4ef878985f8 input=a9049054013a1b77]*/