decoder.c

   1 /*
   2  * This file is part of the libsigrokdecode project.
   3  *
   4  * Copyright (C) 2010 Uwe Hermann <uwe@hermann-uwe.de>
   5  * Copyright (C) 2012 Bert Vermeulen <bert@biot.com>
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "config.h"
  22 #include "libsigrokdecode.h" /* First, so we avoid a _POSIX_C_SOURCE warning. */
  23 #include "libsigrokdecode-internal.h"
  24 #include <glib.h>
  25
  26 /**
  27  * @file
  28  *
  29  * Listing, loading, unloading, and handling protocol decoders.
  30  */
  31
  32 /**
  33  * @defgroup grp_decoder Protocol decoders
  34  *
  35  * Handling protocol decoders.
  36  *
  37  * @{
  38  */
  39
  40 /** @cond PRIVATE */
  41
  42 /* The list of protocol decoders. */
  43 SRD_PRIV GSList *pd_list = NULL;
  44
  45 /* srd.c */
  46 extern GSList *searchpaths;
  47
  48 /* session.c */
  49 extern GSList *sessions;
  50
  51 /* module_sigrokdecode.c */
  52 extern SRD_PRIV PyObject *mod_sigrokdecode;
  53
  54 /** @endcond */
  55
  56 /**
  57  * Returns the list of supported/loaded protocol decoders.
  58  *
  59  * This is a GSList containing the names of the decoders as strings.
  60  *
  61  * @return List of decoders, NULL if none are supported or loaded.
  62  *
  63  * @since 0.1.0 (but the API changed in 0.2.0)
  64  */
  65 SRD_API const GSList *srd_decoder_list(void)
  66 {
  67         return pd_list;
  68 }
  69
  70 /**
  71  * Get the decoder with the specified ID.
  72  *
  73  * @param id The ID string of the decoder to return.
  74  *
  75  * @return The decoder with the specified ID, or NULL if not found.
  76  *
  77  * @since 0.1.0
  78  */
  79 SRD_API struct srd_decoder *srd_decoder_get_by_id(const char *id)
  80 {
  81         GSList *l;
  82         struct srd_decoder *dec;
  83
  84         for (l = pd_list; l; l = l->next) {
  85                 dec = l->data;
  86                 if (!strcmp(dec->id, id))
  87                         return dec;
  88         }
  89
  90         return NULL;
  91 }
  92
  93 static int get_channels(const struct srd_decoder *d, const char *attr,
  94                 GSList **pdchl)
  95 {
  96         PyObject *py_channellist, *py_entry;
  97         struct srd_channel *pdch;
  98         int ret, num_channels, i;
  99
 100         if (!PyObject_HasAttrString(d->py_dec, attr))
 101                 /* No channels of this type specified. */
 102                 return SRD_OK;
 103
 104         py_channellist = PyObject_GetAttrString(d->py_dec, attr);
 105         if (!PyTuple_Check(py_channellist)) {
 106                 srd_err("Protocol decoder %s %s attribute is not a tuple.",
 107                                 d->name, attr);
 108                 return SRD_ERR_PYTHON;
 109         }
 110
 111         if ((num_channels = PyTuple_Size(py_channellist)) == 0)
 112                 /* Empty channellist. */
 113                 return SRD_OK;
 114
 115         ret = SRD_OK;
 116         for (i = 0; i < num_channels; i++) {
 117                 py_entry = PyTuple_GetItem(py_channellist, i);
 118                 if (!PyDict_Check(py_entry)) {
 119                         srd_err("Protocol decoder %s %s attribute is not "
 120                                 "a list with dict elements.", d->name, attr);
 121                         ret = SRD_ERR_PYTHON;
 122                         break;
 123                 }
 124
 125                 if (!(pdch = g_try_malloc(sizeof(struct srd_channel)))) {
 126                         srd_err("Failed to g_malloc() struct srd_channel.");
 127                         ret = SRD_ERR_MALLOC;
 128                         break;
 129                 }
 130
 131                 if ((py_dictitem_as_str(py_entry, "id", &pdch->id)) != SRD_OK) {
 132                         ret = SRD_ERR_PYTHON;
 133                         break;
 134                 }
 135                 if ((py_dictitem_as_str(py_entry, "name", &pdch->name)) != SRD_OK) {
 136                         ret = SRD_ERR_PYTHON;
 137                         break;
 138                 }
 139                 if ((py_dictitem_as_str(py_entry, "desc", &pdch->desc)) != SRD_OK) {
 140                         ret = SRD_ERR_PYTHON;
 141                         break;
 142                 }
 143                 pdch->order = i;
 144
 145                 *pdchl = g_slist_append(*pdchl, pdch);
 146         }
 147
 148         Py_DecRef(py_channellist);
 149
 150         return ret;
 151 }
 152
 153 static int get_options(struct srd_decoder *d)
 154 {
 155         PyObject *py_opts, *py_opt, *py_val, *py_default, *py_item;
 156         Py_ssize_t opt, i;
 157         struct srd_decoder_option *o;
 158         GVariant *gvar;
 159         gint64 lval;
 160         double dval;
 161         int overflow;
 162         char *sval;
 163
 164         if (!PyObject_HasAttrString(d->py_dec, "options"))
 165                 /* No options, that's fine. */
 166                 return SRD_OK;
 167
 168         /* If present, options must be a tuple. */
 169         py_opts = PyObject_GetAttrString(d->py_dec, "options");
 170         if (!PyTuple_Check(py_opts)) {
 171                 srd_err("Protocol decoder %s: options attribute is not "
 172                                 "a tuple.", d->id);
 173                 return SRD_ERR_PYTHON;
 174         }
 175
 176         for (opt = 0; opt < PyTuple_Size(py_opts); opt++) {
 177                 py_opt = PyTuple_GetItem(py_opts, opt);
 178                 if (!PyDict_Check(py_opt)) {
 179                         srd_err("Protocol decoder %s options: each option "
 180                                         "must consist of a dictionary.", d->name);
 181                         return SRD_ERR_PYTHON;
 182                 }
 183                 if (!(py_val = PyDict_GetItemString(py_opt, "id"))) {
 184                         srd_err("Protocol decoder %s option %d has no "
 185                                         "id.", d->name);
 186                         return SRD_ERR_PYTHON;
 187                 }
 188                 o = g_malloc0(sizeof(struct srd_decoder_option));
 189                 py_str_as_str(py_val, &o->id);
 190
 191                 if ((py_val = PyDict_GetItemString(py_opt, "desc")))
 192                         py_str_as_str(py_val, &o->desc);
 193
 194                 if ((py_default = PyDict_GetItemString(py_opt, "default"))) {
 195                         if (PyUnicode_Check(py_default)) {
 196                                 /* UTF-8 string */
 197                                 py_str_as_str(py_default, &sval);
 198                                 o->def = g_variant_new_string(sval);
 199                                 g_free(sval);
 200                         } else if (PyLong_Check(py_default)) {
 201                                 /* Long */
 202                                 lval = PyLong_AsLongAndOverflow(py_default, &overflow);
 203                                 if (overflow) {
 204                                         /* Value is < LONG_MIN or > LONG_MAX */
 205                                         PyErr_Clear();
 206                                         srd_err("Protocol decoder %s option 'default' has "
 207                                                         "invalid default value.", d->name);
 208                                         return SRD_ERR_PYTHON;
 209                                 }
 210                                 o->def = g_variant_new_int64(lval);
 211                         } else if (PyFloat_Check(py_default)) {
 212                                 /* Float */
 213                                 if ((dval = PyFloat_AsDouble(py_default)) == -1.0) {
 214                                         PyErr_Clear();
 215                                         srd_err("Protocol decoder %s option 'default' has "
 216                                                         "invalid default value.", d->name);
 217                                         return SRD_ERR_PYTHON;
 218                                 }
 219                                 o->def = g_variant_new_double(dval);
 220                         } else {
 221                                 srd_err("Protocol decoder %s option 'default' has "
 222                                                 "value of unsupported type '%s'.", d->name,
 223                                                 Py_TYPE(py_default)->tp_name);
 224                                 return SRD_ERR_PYTHON;
 225                         }
 226                         g_variant_ref_sink(o->def);
 227                 }
 228
 229                 if ((py_val = PyDict_GetItemString(py_opt, "values"))) {
 230                         /* A default is required if a list of values is
 231                          * given, since it's used to verify their type. */
 232                         if (!o->def) {
 233                                 srd_err("No default for option '%s'", o->id);
 234                                 return SRD_ERR_PYTHON;
 235                         }
 236                         if (!PyTuple_Check(py_val)) {
 237                                 srd_err("Option '%s' values should be a tuple.", o->id);
 238                                 return SRD_ERR_PYTHON;
 239                         }
 240                         for (i = 0; i < PyTuple_Size(py_val); i++) {
 241                                 py_item = PyTuple_GetItem(py_val, i);
 242                                 if (Py_TYPE(py_default) != Py_TYPE(py_item)) {
 243                                         srd_err("All values for option '%s' must be "
 244                                                         "of the same type as the default.",
 245                                                         o->id);
 246                                         return SRD_ERR_PYTHON;
 247                                 }
 248                                 if (PyUnicode_Check(py_item)) {
 249                                         /* UTF-8 string */
 250                                         py_str_as_str(py_item, &sval);
 251                                         gvar = g_variant_new_string(sval);
 252                                         g_variant_ref_sink(gvar);
 253                                         g_free(sval);
 254                                         o->values = g_slist_append(o->values, gvar);
 255                                 } else if (PyLong_Check(py_item)) {
 256                                         /* Long */
 257                                         lval = PyLong_AsLongAndOverflow(py_item, &overflow);
 258                                         if (overflow) {
 259                                                 /* Value is < LONG_MIN or > LONG_MAX */
 260                                                 PyErr_Clear();
 261                                                 srd_err("Protocol decoder %s option 'values' "
 262                                                                 "has invalid value.", d->name);
 263                                                 return SRD_ERR_PYTHON;
 264                                         }
 265                                         gvar = g_variant_new_int64(lval);
 266                                         g_variant_ref_sink(gvar);
 267                                         o->values = g_slist_append(o->values, gvar);
 268                                 } else if (PyFloat_Check(py_item)) {
 269                                         /* Float */
 270                                         if ((dval = PyFloat_AsDouble(py_item)) == -1.0) {
 271                                                 PyErr_Clear();
 272                                                 srd_err("Protocol decoder %s option 'default' has "
 273                                                                 "invalid default value.", d->name);
 274                                                 return SRD_ERR_PYTHON;
 275                                         }
 276                                         gvar = g_variant_new_double(dval);
 277                                         g_variant_ref_sink(gvar);
 278                                         o->values = g_slist_append(o->values, gvar);
 279                                 }
 280                         }
 281                 }
 282                 d->options = g_slist_append(d->options, o);
 283         }
 284
 285         return SRD_OK;
 286 }
 287
 288 /**
 289  * Load a protocol decoder module into the embedded Python interpreter.
 290  *
 291  * @param module_name The module name to be loaded.
 292  *
 293  * @return SRD_OK upon success, a (negative) error code otherwise.
 294  *
 295  * @since 0.1.0
 296  */
 297 SRD_API int srd_decoder_load(const char *module_name)
 298 {
 299         PyObject *py_basedec, *py_method, *py_attr, *py_annlist, *py_ann;
 300         PyObject *py_bin_classes, *py_bin_class, *py_ann_rows, *py_ann_row;
 301         PyObject *py_ann_classes, *py_long;
 302         struct srd_decoder *d;
 303         int ret, i, j;
 304         char **ann, **bin, *ann_row_id, *ann_row_desc;
 305         struct srd_channel *pdch;
 306         GSList *l, *ann_classes;
 307         struct srd_decoder_annotation_row *ann_row;
 308
 309         if (!srd_check_init())
 310                 return SRD_ERR;
 311
 312         if (!module_name)
 313                 return SRD_ERR_ARG;
 314
 315         if (PyDict_GetItemString(PyImport_GetModuleDict(), module_name)) {
 316                 /* Module was already imported. */
 317                 return SRD_OK;
 318         }
 319
 320         srd_dbg("Loading protocol decoder '%s'.", module_name);
 321
 322         py_basedec = py_method = py_attr = NULL;
 323
 324         if (!(d = g_try_malloc0(sizeof(struct srd_decoder)))) {
 325                 srd_dbg("Failed to g_malloc() struct srd_decoder.");
 326                 ret = SRD_ERR_MALLOC;
 327                 goto err_out;
 328         }
 329
 330         ret = SRD_ERR_PYTHON;
 331
 332         /* Import the Python module. */
 333         if (!(d->py_mod = PyImport_ImportModule(module_name))) {
 334                 srd_exception_catch("Import of '%s' failed.", module_name);
 335                 goto err_out;
 336         }
 337
 338         /* Get the 'Decoder' class as Python object. */
 339         if (!(d->py_dec = PyObject_GetAttrString(d->py_mod, "Decoder"))) {
 340                 /* This generated an AttributeError exception. */
 341                 PyErr_Clear();
 342                 srd_err("Decoder class not found in protocol decoder %s.",
 343                         module_name);
 344                 goto err_out;
 345         }
 346
 347         if (!(py_basedec = PyObject_GetAttrString(mod_sigrokdecode, "Decoder"))) {
 348                 srd_dbg("sigrokdecode module not loaded.");
 349                 goto err_out;
 350         }
 351
 352         if (!PyObject_IsSubclass(d->py_dec, py_basedec)) {
 353                 srd_err("Decoder class in protocol decoder module %s is not "
 354                         "a subclass of sigrokdecode.Decoder.", module_name);
 355                 goto err_out;
 356         }
 357         Py_CLEAR(py_basedec);
 358
 359         /* Check for a proper start() method. */
 360         if (!PyObject_HasAttrString(d->py_dec, "start")) {
 361                 srd_err("Protocol decoder %s has no start() method Decoder "
 362                         "class.", module_name);
 363                 goto err_out;
 364         }
 365         py_method = PyObject_GetAttrString(d->py_dec, "start");
 366         if (!PyFunction_Check(py_method)) {
 367                 srd_err("Protocol decoder %s Decoder class attribute 'start' "
 368                         "is not a method.", module_name);
 369                 goto err_out;
 370         }
 371         Py_CLEAR(py_method);
 372
 373         /* Check for a proper decode() method. */
 374         if (!PyObject_HasAttrString(d->py_dec, "decode")) {
 375                 srd_err("Protocol decoder %s has no decode() method Decoder "
 376                         "class.", module_name);
 377                 goto err_out;
 378         }
 379         py_method = PyObject_GetAttrString(d->py_dec, "decode");
 380         if (!PyFunction_Check(py_method)) {
 381                 srd_err("Protocol decoder %s Decoder class attribute 'decode' "
 382                         "is not a method.", module_name);
 383                 goto err_out;
 384         }
 385         Py_CLEAR(py_method);
 386
 387         /* Store required fields in newly allocated strings. */
 388         if (py_attr_as_str(d->py_dec, "id", &(d->id)) != SRD_OK)
 389                 goto err_out;
 390
 391         if (py_attr_as_str(d->py_dec, "name", &(d->name)) != SRD_OK)
 392                 goto err_out;
 393
 394         if (py_attr_as_str(d->py_dec, "longname", &(d->longname)) != SRD_OK)
 395                 goto err_out;
 396
 397         if (py_attr_as_str(d->py_dec, "desc", &(d->desc)) != SRD_OK)
 398                 goto err_out;
 399
 400         if (py_attr_as_str(d->py_dec, "license", &(d->license)) != SRD_OK)
 401                 goto err_out;
 402
 403         /* All options and their default values. */
 404         if (get_options(d) != SRD_OK)
 405                 goto err_out;
 406
 407         /* Check and import required channels. */
 408         if (get_channels(d, "channels", &d->channels) != SRD_OK)
 409                 goto err_out;
 410
 411         /* Check and import optional channels. */
 412         if (get_channels(d, "optional_channels", &d->opt_channels) != SRD_OK)
 413                 goto err_out;
 414
 415         /*
 416          * Fix order numbers for the optional channels.
 417          *
 418          * Example:
 419          * Required channels: r1, r2, r3. Optional: o1, o2, o3, o4.
 420          * 'order' fields in the d->channels list = 0, 1, 2.
 421          * 'order' fields in the d->opt_channels list = 3, 4, 5, 6.
 422          */
 423         for (l = d->opt_channels; l; l = l->next) {
 424                 pdch = l->data;
 425                 pdch->order += g_slist_length(d->channels);
 426         }
 427
 428         /* Convert annotation class attribute to GSList of char **. */
 429         d->annotations = NULL;
 430         if (PyObject_HasAttrString(d->py_dec, "annotations")) {
 431                 py_annlist = PyObject_GetAttrString(d->py_dec, "annotations");
 432                 if (!PyTuple_Check(py_annlist)) {
 433                         srd_err("Protocol decoder %s annotations should "
 434                                         "be a tuple.", module_name);
 435                         goto err_out;
 436                 }
 437                 for (i = 0; i < PyTuple_Size(py_annlist); i++) {
 438                         py_ann = PyTuple_GetItem(py_annlist, i);
 439                         if (!PyTuple_Check(py_ann) || PyTuple_Size(py_ann) != 2) {
 440                                 srd_err("Protocol decoder %s annotation %d should "
 441                                                 "be a tuple with two elements.", module_name, i + 1);
 442                                 goto err_out;
 443                         }
 444
 445                         if (py_strseq_to_char(py_ann, &ann) != SRD_OK) {
 446                                 goto err_out;
 447                         }
 448                         d->annotations = g_slist_append(d->annotations, ann);
 449                 }
 450         }
 451
 452         /* Convert annotation_rows to GSList of 'struct srd_decoder_annotation_row'. */
 453         d->annotation_rows = NULL;
 454         if (PyObject_HasAttrString(d->py_dec, "annotation_rows")) {
 455                 py_ann_rows = PyObject_GetAttrString(d->py_dec, "annotation_rows");
 456                 if (!PyTuple_Check(py_ann_rows)) {
 457                         srd_err("Protocol decoder %s annotation row list "
 458                                 "must be a tuple.", module_name);
 459                         goto err_out;
 460                 }
 461                 for (i = 0; i < PyTuple_Size(py_ann_rows); i++) {
 462                         py_ann_row = PyTuple_GetItem(py_ann_rows, i);
 463                         if (!PyTuple_Check(py_ann_row)) {
 464                                 srd_err("Protocol decoder %s annotation rows "
 465                                         "must be tuples.", module_name);
 466                                 goto err_out;
 467                         }
 468                         if (PyTuple_Size(py_ann_row) != 3
 469                                         || !PyUnicode_Check(PyTuple_GetItem(py_ann_row, 0))
 470                                         || !PyUnicode_Check(PyTuple_GetItem(py_ann_row, 1))
 471                                         || !PyTuple_Check(PyTuple_GetItem(py_ann_row, 2))) {
 472                                 srd_err("Protocol decoder %s annotation rows "
 473                                         "must contain tuples containing two "
 474                                         "strings and a tuple.", module_name);
 475                                 goto err_out;
 476                         }
 477
 478                         if (py_str_as_str(PyTuple_GetItem(py_ann_row, 0), &ann_row_id) != SRD_OK)
 479                                 goto err_out;
 480
 481                         if (py_str_as_str(PyTuple_GetItem(py_ann_row, 1), &ann_row_desc) != SRD_OK)
 482                                 goto err_out;
 483
 484                         py_ann_classes = PyTuple_GetItem(py_ann_row, 2);
 485                         ann_classes = NULL;
 486                         for (j = 0; j < PyTuple_Size(py_ann_classes); j++) {
 487                                 py_long = PyTuple_GetItem(py_ann_classes, j);
 488                                 if (!PyLong_Check(py_long)) {
 489                                         srd_err("Protocol decoder %s annotation row class "
 490                                                 "list must only contain numbers.", module_name);
 491                                         goto err_out;
 492                                 }
 493                                 ann_classes = g_slist_append(ann_classes,
 494                                         GINT_TO_POINTER(PyLong_AsLong(py_long)));
 495                         }
 496
 497                         ann_row = g_malloc0(sizeof(struct srd_decoder_annotation_row));
 498                         ann_row->id = ann_row_id;
 499                         ann_row->desc = ann_row_desc;
 500                         ann_row->ann_classes = ann_classes;
 501                         d->annotation_rows = g_slist_append(d->annotation_rows, ann_row);
 502                 }
 503         }
 504
 505         /* Convert binary class to GSList of char *. */
 506         d->binary = NULL;
 507         if (PyObject_HasAttrString(d->py_dec, "binary")) {
 508                 py_bin_classes = PyObject_GetAttrString(d->py_dec, "binary");
 509                 if (!PyTuple_Check(py_bin_classes)) {
 510                         srd_err("Protocol decoder %s binary classes should "
 511                                         "be a tuple.", module_name);
 512                         goto err_out;
 513                 }
 514                 for (i = 0; i < PyTuple_Size(py_bin_classes); i++) {
 515                         py_bin_class = PyTuple_GetItem(py_bin_classes, i);
 516                         if (!PyTuple_Check(py_bin_class)) {
 517                                 srd_err("Protocol decoder %s binary classes "
 518                                                 "should consist of tuples.", module_name);
 519                                 goto err_out;
 520                         }
 521                         if (PyTuple_Size(py_bin_class) != 2
 522                                         || !PyUnicode_Check(PyTuple_GetItem(py_bin_class, 0))
 523                                         || !PyUnicode_Check(PyTuple_GetItem(py_bin_class, 1))) {
 524                                 srd_err("Protocol decoder %s binary classes should "
 525                                                 "contain tuples with two strings.", module_name);
 526                                 goto err_out;
 527                         }
 528
 529                         if (py_strseq_to_char(py_bin_class, &bin) != SRD_OK) {
 530                                 goto err_out;
 531                         }
 532                         d->binary = g_slist_append(d->binary, bin);
 533                 }
 534         }
 535
 536         /* Append it to the list of supported/loaded decoders. */
 537         pd_list = g_slist_append(pd_list, d);
 538
 539         ret = SRD_OK;
 540
 541 err_out:
 542         if (ret != SRD_OK) {
 543                 Py_XDECREF(py_method);
 544                 Py_XDECREF(py_basedec);
 545                 Py_XDECREF(d->py_dec);
 546                 Py_XDECREF(d->py_mod);
 547                 g_free(d);
 548         }
 549
 550         return ret;
 551 }
 552
 553 /**
 554  * Return a protocol decoder's docstring.
 555  *
 556  * @param dec The loaded protocol decoder.
 557  *
 558  * @return A newly allocated buffer containing the protocol decoder's
 559  *         documentation. The caller is responsible for free'ing the buffer.
 560  *
 561  * @since 0.1.0
 562  */
 563 SRD_API char *srd_decoder_doc_get(const struct srd_decoder *dec)
 564 {
 565         PyObject *py_str;
 566         char *doc;
 567
 568         if (!srd_check_init())
 569                 return NULL;
 570
 571         if (!dec)
 572                 return NULL;
 573
 574         if (!PyObject_HasAttrString(dec->py_mod, "__doc__"))
 575                 return NULL;
 576
 577         if (!(py_str = PyObject_GetAttrString(dec->py_mod, "__doc__"))) {
 578                 srd_exception_catch("");
 579                 return NULL;
 580         }
 581
 582         doc = NULL;
 583         if (py_str != Py_None)
 584                 py_str_as_str(py_str, &doc);
 585         Py_DecRef(py_str);
 586
 587         return doc;
 588 }
 589
 590 static void free_channels(GSList *channellist)
 591 {
 592         GSList *l;
 593         struct srd_channel *pdch;
 594
 595         if (channellist == NULL)
 596                 return;
 597
 598         for (l = channellist; l; l = l->next) {
 599                 pdch = l->data;
 600                 g_free(pdch->id);
 601                 g_free(pdch->name);
 602                 g_free(pdch->desc);
 603                 g_free(pdch);
 604         }
 605         g_slist_free(channellist);
 606 }
 607
 608 /**
 609  * Unload the specified protocol decoder.
 610  *
 611  * @param dec The struct srd_decoder to be unloaded.
 612  *
 613  * @return SRD_OK upon success, a (negative) error code otherwise.
 614  *
 615  * @since 0.1.0
 616  */
 617 SRD_API int srd_decoder_unload(struct srd_decoder *dec)
 618 {
 619         struct srd_decoder_option *o;
 620         struct srd_session *sess;
 621         GSList *l;
 622
 623         if (!srd_check_init())
 624                 return SRD_ERR;
 625
 626         if (!dec)
 627                 return SRD_ERR_ARG;
 628
 629         srd_dbg("Unloading protocol decoder '%s'.", dec->name);
 630
 631         /*
 632          * Since any instances of this decoder need to be released as well,
 633          * but they could be anywhere in the stack, just free the entire
 634          * stack. A frontend reloading a decoder thus has to restart all
 635          * instances, and rebuild the stack.
 636          */
 637         for (l = sessions; l; l = l->next) {
 638                 sess = l->data;
 639                 srd_inst_free_all(sess, NULL);
 640         }
 641
 642         for (l = dec->options; l; l = l->next) {
 643                 o = l->data;
 644                 g_free(o->id);
 645                 g_free(o->desc);
 646                 g_variant_unref(o->def);
 647                 g_free(o);
 648         }
 649         g_slist_free(dec->options);
 650
 651         free_channels(dec->channels);
 652         free_channels(dec->opt_channels);
 653         g_free(dec->id);
 654         g_free(dec->name);
 655         g_free(dec->longname);
 656         g_free(dec->desc);
 657         g_free(dec->license);
 658
 659         /* The module's Decoder class. */
 660         Py_XDECREF(dec->py_dec);
 661         /* The module itself. */
 662         Py_XDECREF(dec->py_mod);
 663
 664         g_free(dec);
 665
 666         return SRD_OK;
 667 }
 668
 669 static void srd_decoder_load_all_path(char *path)
 670 {
 671         GDir *dir;
 672         const gchar *direntry;
 673
 674         if (!(dir = g_dir_open(path, 0, NULL)))
 675                 /* Not really fatal */
 676                 return;
 677
 678         /* This ignores errors returned by srd_decoder_load(). That
 679          * function will have logged the cause, but in any case we
 680          * want to continue anyway. */
 681         while ((direntry = g_dir_read_name(dir)) != NULL) {
 682                 /* The directory name is the module name (e.g. "i2c"). */
 683                 srd_decoder_load(direntry);
 684         }
 685         g_dir_close(dir);
 686
 687 }
 688
 689 /**
 690  * Load all installed protocol decoders.
 691  *
 692  * @return SRD_OK upon success, a (negative) error code otherwise.
 693  *
 694  * @since 0.1.0
 695  */
 696 SRD_API int srd_decoder_load_all(void)
 697 {
 698         GSList *l;
 699
 700         if (!srd_check_init())
 701                 return SRD_ERR;
 702
 703         for (l = searchpaths; l; l = l->next)
 704                 srd_decoder_load_all_path(l->data);
 705
 706         return SRD_OK;
 707 }
 708
 709 /**
 710  * Unload all loaded protocol decoders.
 711  *
 712  * @return SRD_OK upon success, a (negative) error code otherwise.
 713  *
 714  * @since 0.1.0
 715  */
 716 SRD_API int srd_decoder_unload_all(void)
 717 {
 718         GSList *l;
 719         struct srd_decoder *dec;
 720
 721         for (l = pd_list; l; l = l->next) {
 722                 dec = l->data;
 723                 srd_decoder_unload(dec);
 724         }
 725         g_slist_free(pd_list);
 726         pd_list = NULL;
 727
 728         return SRD_OK;
 729 }
 730
 731 /** @} */