Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 1 | /* ------------------------------------------------------------------------ |
| 2 | |
| 3 | Python Codec Registry and support functions |
| 4 | |
| 5 | Written by Marc-Andre Lemburg (mal@lemburg.com). |
| 6 | |
| 7 | (c) Copyright CNRI, All Rights Reserved. NO WARRANTY. |
| 8 | |
| 9 | ------------------------------------------------------------------------ */ |
| 10 | |
| 11 | #include "Python.h" |
| 12 | #include <ctype.h> |
| 13 | |
| 14 | /* --- Globals ------------------------------------------------------------ */ |
| 15 | |
| 16 | static PyObject *_PyCodec_SearchPath; |
| 17 | static PyObject *_PyCodec_SearchCache; |
| 18 | |
| 19 | /* Flag used for lazy import of the standard encodings package */ |
| 20 | static int import_encodings_called = 0; |
| 21 | |
| 22 | /* --- Codec Registry ----------------------------------------------------- */ |
| 23 | |
| 24 | /* Import the standard encodings package which will register the first |
| 25 | codec search function. |
| 26 | |
| 27 | This is done in a lazy way so that the Unicode implementation does |
| 28 | not downgrade startup time of scripts not needing it. |
| 29 | |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 30 | ImportErrors are silently ignored by this function. Only one try is |
| 31 | made. |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 32 | |
| 33 | */ |
| 34 | |
| 35 | static |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 36 | int import_encodings() |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 37 | { |
| 38 | PyObject *mod; |
| 39 | |
| 40 | import_encodings_called = 1; |
| 41 | mod = PyImport_ImportModule("encodings"); |
| 42 | if (mod == NULL) { |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 43 | if (PyErr_ExceptionMatches(PyExc_ImportError)) { |
| 44 | /* Ignore ImportErrors... this is done so that |
| 45 | distributions can disable the encodings package. Note |
| 46 | that other errors are not masked, e.g. SystemErrors |
| 47 | raised to inform the user of an error in the Python |
| 48 | configuration are still reported back to the user. */ |
| 49 | PyErr_Clear(); |
| 50 | return 0; |
| 51 | } |
| 52 | return -1; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 53 | } |
| 54 | Py_DECREF(mod); |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 55 | return 0; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 56 | } |
| 57 | |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 58 | int PyCodec_Register(PyObject *search_function) |
| 59 | { |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 60 | if (!import_encodings_called) { |
| 61 | if (import_encodings()) |
| 62 | goto onError; |
| 63 | } |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 64 | if (search_function == NULL) { |
| 65 | PyErr_BadArgument(); |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 66 | goto onError; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 67 | } |
| 68 | if (!PyCallable_Check(search_function)) { |
| 69 | PyErr_SetString(PyExc_TypeError, |
| 70 | "argument must be callable"); |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 71 | goto onError; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 72 | } |
| 73 | return PyList_Append(_PyCodec_SearchPath, search_function); |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 74 | |
| 75 | onError: |
| 76 | return -1; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 77 | } |
| 78 | |
Guido van Rossum | 9e896b3 | 2000-04-05 20:11:21 +0000 | [diff] [blame] | 79 | /* Convert a string to a normalized Python string: all characters are |
| 80 | converted to lower case, spaces are replaced with underscores. */ |
| 81 | |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 82 | static |
Guido van Rossum | 9e896b3 | 2000-04-05 20:11:21 +0000 | [diff] [blame] | 83 | PyObject *normalizestring(const char *string) |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 84 | { |
| 85 | register int i; |
| 86 | int len = strlen(string); |
| 87 | char *p; |
| 88 | PyObject *v; |
| 89 | |
| 90 | v = PyString_FromStringAndSize(NULL, len); |
| 91 | if (v == NULL) |
| 92 | return NULL; |
| 93 | p = PyString_AS_STRING(v); |
Guido van Rossum | 9e896b3 | 2000-04-05 20:11:21 +0000 | [diff] [blame] | 94 | for (i = 0; i < len; i++) { |
| 95 | register char ch = string[i]; |
| 96 | if (ch == ' ') |
| 97 | ch = '-'; |
| 98 | else |
| 99 | ch = tolower(ch); |
| 100 | p[i] = ch; |
| 101 | } |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 102 | return v; |
| 103 | } |
| 104 | |
| 105 | /* Lookup the given encoding and return a tuple providing the codec |
| 106 | facilities. |
| 107 | |
| 108 | The encoding string is looked up converted to all lower-case |
| 109 | characters. This makes encodings looked up through this mechanism |
| 110 | effectively case-insensitive. |
| 111 | |
Fred Drake | 766de83 | 2000-05-09 19:55:59 +0000 | [diff] [blame^] | 112 | If no codec is found, a LookupError is set and NULL returned. |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 113 | |
| 114 | As side effect, this tries to load the encodings package, if not |
| 115 | yet done. This is part of the lazy load strategy for the encodings |
| 116 | package. |
| 117 | |
| 118 | */ |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 119 | |
| 120 | PyObject *_PyCodec_Lookup(const char *encoding) |
| 121 | { |
Guido van Rossum | 5ba3c84 | 2000-03-24 20:52:23 +0000 | [diff] [blame] | 122 | PyObject *result, *args = NULL, *v; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 123 | int i, len; |
| 124 | |
Fred Drake | 766de83 | 2000-05-09 19:55:59 +0000 | [diff] [blame^] | 125 | if (encoding == NULL) { |
| 126 | PyErr_BadArgument(); |
| 127 | goto onError; |
| 128 | } |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 129 | if (_PyCodec_SearchCache == NULL || |
| 130 | _PyCodec_SearchPath == NULL) { |
Barry Warsaw | 51ac580 | 2000-03-20 16:36:48 +0000 | [diff] [blame] | 131 | PyErr_SetString(PyExc_SystemError, |
| 132 | "codec module not properly initialized"); |
| 133 | goto onError; |
| 134 | } |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 135 | if (!import_encodings_called) { |
| 136 | if (import_encodings()) |
| 137 | goto onError; |
| 138 | } |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 139 | |
Guido van Rossum | 9e896b3 | 2000-04-05 20:11:21 +0000 | [diff] [blame] | 140 | /* Convert the encoding to a normalized Python string: all |
| 141 | characters are converted to lower case, spaces and hypens are |
| 142 | replaced with underscores. */ |
| 143 | v = normalizestring(encoding); |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 144 | if (v == NULL) |
| 145 | goto onError; |
| 146 | PyString_InternInPlace(&v); |
| 147 | |
| 148 | /* First, try to lookup the name in the registry dictionary */ |
| 149 | result = PyDict_GetItem(_PyCodec_SearchCache, v); |
| 150 | if (result != NULL) { |
| 151 | Py_INCREF(result); |
Barry Warsaw | 51ac580 | 2000-03-20 16:36:48 +0000 | [diff] [blame] | 152 | Py_DECREF(v); |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 153 | return result; |
| 154 | } |
| 155 | |
| 156 | /* Next, scan the search functions in order of registration */ |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 157 | args = PyTuple_New(1); |
| 158 | if (args == NULL) |
| 159 | goto onError; |
| 160 | PyTuple_SET_ITEM(args,0,v); |
Guido van Rossum | 5ba3c84 | 2000-03-24 20:52:23 +0000 | [diff] [blame] | 161 | |
| 162 | len = PyList_Size(_PyCodec_SearchPath); |
| 163 | if (len < 0) |
| 164 | goto onError; |
Guido van Rossum | b95de4f | 2000-03-31 17:25:23 +0000 | [diff] [blame] | 165 | if (len == 0) { |
| 166 | PyErr_SetString(PyExc_LookupError, |
| 167 | "no codec search functions registered: " |
| 168 | "can't find encoding"); |
| 169 | goto onError; |
| 170 | } |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 171 | |
| 172 | for (i = 0; i < len; i++) { |
| 173 | PyObject *func; |
| 174 | |
| 175 | func = PyList_GetItem(_PyCodec_SearchPath, i); |
| 176 | if (func == NULL) |
| 177 | goto onError; |
Guido van Rossum | 5ba3c84 | 2000-03-24 20:52:23 +0000 | [diff] [blame] | 178 | result = PyEval_CallObject(func, args); |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 179 | if (result == NULL) |
| 180 | goto onError; |
| 181 | if (result == Py_None) { |
| 182 | Py_DECREF(result); |
| 183 | continue; |
| 184 | } |
| 185 | if (!PyTuple_Check(result) || PyTuple_GET_SIZE(result) != 4) { |
| 186 | PyErr_SetString(PyExc_TypeError, |
| 187 | "codec search functions must return 4-tuples"); |
| 188 | Py_DECREF(result); |
| 189 | goto onError; |
| 190 | } |
| 191 | break; |
| 192 | } |
| 193 | if (i == len) { |
| 194 | /* XXX Perhaps we should cache misses too ? */ |
| 195 | PyErr_SetString(PyExc_LookupError, |
Barry Warsaw | 51ac580 | 2000-03-20 16:36:48 +0000 | [diff] [blame] | 196 | "unknown encoding"); |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 197 | goto onError; |
| 198 | } |
| 199 | |
| 200 | /* Cache and return the result */ |
| 201 | PyDict_SetItem(_PyCodec_SearchCache, v, result); |
| 202 | Py_DECREF(args); |
| 203 | return result; |
| 204 | |
| 205 | onError: |
| 206 | Py_XDECREF(args); |
| 207 | return NULL; |
| 208 | } |
| 209 | |
| 210 | static |
| 211 | PyObject *args_tuple(PyObject *object, |
| 212 | const char *errors) |
| 213 | { |
| 214 | PyObject *args; |
| 215 | |
| 216 | args = PyTuple_New(1 + (errors != NULL)); |
| 217 | if (args == NULL) |
| 218 | return NULL; |
| 219 | Py_INCREF(object); |
| 220 | PyTuple_SET_ITEM(args,0,object); |
| 221 | if (errors) { |
| 222 | PyObject *v; |
| 223 | |
| 224 | v = PyString_FromString(errors); |
| 225 | if (v == NULL) { |
| 226 | Py_DECREF(args); |
| 227 | return NULL; |
| 228 | } |
| 229 | PyTuple_SET_ITEM(args, 1, v); |
| 230 | } |
| 231 | return args; |
| 232 | } |
| 233 | |
| 234 | /* Build a codec by calling factory(stream[,errors]) or just |
| 235 | factory(errors) depending on whether the given parameters are |
| 236 | non-NULL. */ |
| 237 | |
| 238 | static |
| 239 | PyObject *build_stream_codec(PyObject *factory, |
| 240 | PyObject *stream, |
| 241 | const char *errors) |
| 242 | { |
| 243 | PyObject *args, *codec; |
| 244 | |
| 245 | args = args_tuple(stream, errors); |
| 246 | if (args == NULL) |
| 247 | return NULL; |
| 248 | |
| 249 | codec = PyEval_CallObject(factory, args); |
| 250 | Py_DECREF(args); |
| 251 | return codec; |
| 252 | } |
| 253 | |
| 254 | /* Convenience APIs to query the Codec registry. |
| 255 | |
| 256 | All APIs return a codec object with incremented refcount. |
| 257 | |
| 258 | */ |
| 259 | |
| 260 | PyObject *PyCodec_Encoder(const char *encoding) |
| 261 | { |
| 262 | PyObject *codecs; |
| 263 | PyObject *v; |
| 264 | |
| 265 | codecs = _PyCodec_Lookup(encoding); |
| 266 | if (codecs == NULL) |
| 267 | goto onError; |
| 268 | v = PyTuple_GET_ITEM(codecs,0); |
| 269 | Py_INCREF(v); |
| 270 | return v; |
| 271 | |
| 272 | onError: |
| 273 | return NULL; |
| 274 | } |
| 275 | |
| 276 | PyObject *PyCodec_Decoder(const char *encoding) |
| 277 | { |
| 278 | PyObject *codecs; |
| 279 | PyObject *v; |
| 280 | |
| 281 | codecs = _PyCodec_Lookup(encoding); |
| 282 | if (codecs == NULL) |
| 283 | goto onError; |
| 284 | v = PyTuple_GET_ITEM(codecs,1); |
| 285 | Py_INCREF(v); |
| 286 | return v; |
| 287 | |
| 288 | onError: |
| 289 | return NULL; |
| 290 | } |
| 291 | |
| 292 | PyObject *PyCodec_StreamReader(const char *encoding, |
| 293 | PyObject *stream, |
| 294 | const char *errors) |
| 295 | { |
| 296 | PyObject *codecs; |
| 297 | |
| 298 | codecs = _PyCodec_Lookup(encoding); |
| 299 | if (codecs == NULL) |
| 300 | goto onError; |
| 301 | return build_stream_codec(PyTuple_GET_ITEM(codecs,2),stream,errors); |
| 302 | |
| 303 | onError: |
| 304 | return NULL; |
| 305 | } |
| 306 | |
| 307 | PyObject *PyCodec_StreamWriter(const char *encoding, |
| 308 | PyObject *stream, |
| 309 | const char *errors) |
| 310 | { |
| 311 | PyObject *codecs; |
| 312 | |
| 313 | codecs = _PyCodec_Lookup(encoding); |
| 314 | if (codecs == NULL) |
| 315 | goto onError; |
| 316 | return build_stream_codec(PyTuple_GET_ITEM(codecs,3),stream,errors); |
| 317 | |
| 318 | onError: |
| 319 | return NULL; |
| 320 | } |
| 321 | |
| 322 | /* Encode an object (e.g. an Unicode object) using the given encoding |
| 323 | and return the resulting encoded object (usually a Python string). |
| 324 | |
| 325 | errors is passed to the encoder factory as argument if non-NULL. */ |
| 326 | |
| 327 | PyObject *PyCodec_Encode(PyObject *object, |
| 328 | const char *encoding, |
| 329 | const char *errors) |
| 330 | { |
| 331 | PyObject *encoder = NULL; |
| 332 | PyObject *args = NULL, *result; |
| 333 | PyObject *v; |
| 334 | |
| 335 | encoder = PyCodec_Encoder(encoding); |
| 336 | if (encoder == NULL) |
| 337 | goto onError; |
| 338 | |
| 339 | args = args_tuple(object, errors); |
| 340 | if (args == NULL) |
| 341 | goto onError; |
| 342 | |
| 343 | result = PyEval_CallObject(encoder,args); |
| 344 | if (result == NULL) |
| 345 | goto onError; |
| 346 | |
| 347 | if (!PyTuple_Check(result) || |
| 348 | PyTuple_GET_SIZE(result) != 2) { |
| 349 | PyErr_SetString(PyExc_TypeError, |
| 350 | "encoder must return a tuple (object,integer)"); |
| 351 | goto onError; |
| 352 | } |
| 353 | v = PyTuple_GET_ITEM(result,0); |
| 354 | Py_INCREF(v); |
| 355 | /* We don't check or use the second (integer) entry. */ |
| 356 | |
| 357 | Py_DECREF(args); |
| 358 | Py_DECREF(encoder); |
| 359 | Py_DECREF(result); |
| 360 | return v; |
| 361 | |
| 362 | onError: |
| 363 | Py_XDECREF(args); |
| 364 | Py_XDECREF(encoder); |
| 365 | return NULL; |
| 366 | } |
| 367 | |
| 368 | /* Decode an object (usually a Python string) using the given encoding |
| 369 | and return an equivalent object (e.g. an Unicode object). |
| 370 | |
| 371 | errors is passed to the decoder factory as argument if non-NULL. */ |
| 372 | |
| 373 | PyObject *PyCodec_Decode(PyObject *object, |
| 374 | const char *encoding, |
| 375 | const char *errors) |
| 376 | { |
| 377 | PyObject *decoder = NULL; |
| 378 | PyObject *args = NULL, *result = NULL; |
| 379 | PyObject *v; |
| 380 | |
| 381 | decoder = PyCodec_Decoder(encoding); |
| 382 | if (decoder == NULL) |
| 383 | goto onError; |
| 384 | |
| 385 | args = args_tuple(object, errors); |
| 386 | if (args == NULL) |
| 387 | goto onError; |
| 388 | |
| 389 | result = PyEval_CallObject(decoder,args); |
| 390 | if (result == NULL) |
| 391 | goto onError; |
| 392 | if (!PyTuple_Check(result) || |
| 393 | PyTuple_GET_SIZE(result) != 2) { |
| 394 | PyErr_SetString(PyExc_TypeError, |
| 395 | "decoder must return a tuple (object,integer)"); |
| 396 | goto onError; |
| 397 | } |
| 398 | v = PyTuple_GET_ITEM(result,0); |
| 399 | Py_INCREF(v); |
| 400 | /* We don't check or use the second (integer) entry. */ |
| 401 | |
| 402 | Py_DECREF(args); |
| 403 | Py_DECREF(decoder); |
| 404 | Py_DECREF(result); |
| 405 | return v; |
| 406 | |
| 407 | onError: |
| 408 | Py_XDECREF(args); |
| 409 | Py_XDECREF(decoder); |
| 410 | Py_XDECREF(result); |
| 411 | return NULL; |
| 412 | } |
| 413 | |
| 414 | void _PyCodecRegistry_Init() |
| 415 | { |
| 416 | if (_PyCodec_SearchPath == NULL) |
| 417 | _PyCodec_SearchPath = PyList_New(0); |
| 418 | if (_PyCodec_SearchCache == NULL) |
| 419 | _PyCodec_SearchCache = PyDict_New(); |
| 420 | if (_PyCodec_SearchPath == NULL || |
| 421 | _PyCodec_SearchCache == NULL) |
| 422 | Py_FatalError("can't intialize codec registry"); |
| 423 | } |
| 424 | |
| 425 | void _PyCodecRegistry_Fini() |
| 426 | { |
| 427 | Py_XDECREF(_PyCodec_SearchPath); |
Barry Warsaw | 51ac580 | 2000-03-20 16:36:48 +0000 | [diff] [blame] | 428 | _PyCodec_SearchPath = NULL; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 429 | Py_XDECREF(_PyCodec_SearchCache); |
Barry Warsaw | 51ac580 | 2000-03-20 16:36:48 +0000 | [diff] [blame] | 430 | _PyCodec_SearchCache = NULL; |
Guido van Rossum | feee4b9 | 2000-03-10 22:57:27 +0000 | [diff] [blame] | 431 | } |