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 *
_io_open(PyObject * module,PyObject * const * args,Py_ssize_t nargs,PyObject * kwnames)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 *
_io_text_encoding(PyObject * module,PyObject * const * args,Py_ssize_t nargs)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 *
_io_open_code(PyObject * module,PyObject * const * args,Py_ssize_t nargs,PyObject * kwnames)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]*/
359