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-internal.h" /* First, so we avoid a _POSIX_C_SOURCE warning. */
  23 #include "libsigrokdecode.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 loaded protocol decoders. */
  43 static GSList *pd_list = NULL;
  44
  45 /* srd.c */
  46 extern SRD_PRIV GSList *searchpaths;
  47
  48 /* session.c */
  49 extern SRD_PRIV GSList *sessions;
  50 extern SRD_PRIV int max_session_id;
  51
  52 /* module_sigrokdecode.c */
  53 extern SRD_PRIV PyObject *mod_sigrokdecode;
  54
  55 /** @endcond */
  56
  57 static gboolean srd_check_init(void)
  58 {
  59         if (max_session_id < 0) {
  60                 srd_err("Library is not initialized.");
  61                 return FALSE;
  62         } else
  63                 return TRUE;
  64 }
  65
  66 /**
  67  * Returns the list of loaded protocol decoders.
  68  *
  69  * This is a GSList of pointers to struct srd_decoder items.
  70  *
  71  * @return List of decoders, NULL if none are supported or loaded.
  72  *
  73  * @since 0.2.0
  74  */
  75 SRD_API const GSList *srd_decoder_list(void)
  76 {
  77         return pd_list;
  78 }
  79
  80 /**
  81  * Get the decoder with the specified ID.
  82  *
  83  * @param id The ID string of the decoder to return.
  84  *
  85  * @return The decoder with the specified ID, or NULL if not found.
  86  *
  87  * @since 0.1.0
  88  */
  89 SRD_API struct srd_decoder *srd_decoder_get_by_id(const char *id)
  90 {
  91         GSList *l;
  92         struct srd_decoder *dec;
  93
  94         for (l = pd_list; l; l = l->next) {
  95                 dec = l->data;
  96                 if (!strcmp(dec->id, id))
  97                         return dec;
  98         }
  99
 100         return NULL;
 101 }
 102
 103 static void channel_free(void *data)
 104 {
 105         struct srd_channel *ch = data;
 106
 107         if (!ch)
 108                 return;
 109
 110         g_free(ch->desc);
 111         g_free(ch->name);
 112         g_free(ch->id);
 113         g_free(ch);
 114 }
 115
 116 static void variant_free(void *data)
 117 {
 118         GVariant *var = data;
 119
 120         if (!var)
 121                 return;
 122
 123         g_variant_unref(var);
 124 }
 125
 126 static void annotation_row_free(void *data)
 127 {
 128         struct srd_decoder_annotation_row *row = data;
 129
 130         if (!row)
 131                 return;
 132
 133         g_slist_free(row->ann_classes);
 134         g_free(row->desc);
 135         g_free(row->id);
 136         g_free(row);
 137 }
 138
 139 static void logic_output_channel_free(void *data)
 140 {
 141         struct srd_decoder_logic_output_channel *logic_out_ch = data;
 142
 143         if (!logic_out_ch)
 144                 return;
 145
 146         g_free(logic_out_ch->desc);
 147         g_free(logic_out_ch->id);
 148         g_free(logic_out_ch);
 149 }
 150
 151 static void decoder_option_free(void *data)
 152 {
 153         struct srd_decoder_option *opt = data;
 154
 155         if (!opt)
 156                 return;
 157
 158         g_slist_free_full(opt->values, &variant_free);
 159         variant_free(opt->def);
 160         g_free(opt->desc);
 161         g_free(opt->id);
 162         g_free(opt);
 163 }
 164
 165 static void decoder_free(struct srd_decoder *dec)
 166 {
 167         PyGILState_STATE gstate;
 168
 169         if (!dec)
 170                 return;
 171
 172         gstate = PyGILState_Ensure();
 173         Py_XDECREF(dec->py_dec);
 174         Py_XDECREF(dec->py_mod);
 175         PyGILState_Release(gstate);
 176
 177         g_slist_free_full(dec->options, &decoder_option_free);
 178         g_slist_free_full(dec->binary, (GDestroyNotify)&g_strfreev);
 179         g_slist_free_full(dec->annotation_rows, &annotation_row_free);
 180         g_slist_free_full(dec->annotations, (GDestroyNotify)&g_strfreev);
 181         g_slist_free_full(dec->opt_channels, &channel_free);
 182         g_slist_free_full(dec->channels, &channel_free);
 183
 184         g_slist_free_full(dec->outputs, g_free);
 185         g_slist_free_full(dec->inputs, g_free);
 186         g_slist_free_full(dec->tags, g_free);
 187         g_free(dec->license);
 188         g_free(dec->desc);
 189         g_free(dec->longname);
 190         g_free(dec->name);
 191         g_free(dec->id);
 192
 193         g_free(dec);
 194 }
 195
 196 static int get_channels(const struct srd_decoder *d, const char *attr,
 197                 GSList **out_pdchl, int offset)
 198 {
 199         PyObject *py_channellist, *py_entry;
 200         struct srd_channel *pdch;
 201         GSList *pdchl;
 202         ssize_t i;
 203         PyGILState_STATE gstate;
 204
 205         gstate = PyGILState_Ensure();
 206
 207         if (!PyObject_HasAttrString(d->py_dec, attr)) {
 208                 /* No channels of this type specified. */
 209                 PyGILState_Release(gstate);
 210                 return SRD_OK;
 211         }
 212
 213         pdchl = NULL;
 214
 215         py_channellist = PyObject_GetAttrString(d->py_dec, attr);
 216         if (!py_channellist)
 217                 goto except_out;
 218
 219         if (!PyTuple_Check(py_channellist)) {
 220                 srd_err("Protocol decoder %s %s attribute is not a tuple.",
 221                         d->name, attr);
 222                 goto err_out;
 223         }
 224
 225         for (i = PyTuple_Size(py_channellist) - 1; i >= 0; i--) {
 226                 py_entry = PyTuple_GetItem(py_channellist, i);
 227                 if (!py_entry)
 228                         goto except_out;
 229
 230                 if (!PyDict_Check(py_entry)) {
 231                         srd_err("Protocol decoder %s %s attribute is not "
 232                                 "a list of dict elements.", d->name, attr);
 233                         goto err_out;
 234                 }
 235                 pdch = g_malloc(sizeof(struct srd_channel));
 236                 /* Add to list right away so it doesn't get lost. */
 237                 pdchl = g_slist_prepend(pdchl, pdch);
 238
 239                 if (py_dictitem_as_str(py_entry, "id", &pdch->id) != SRD_OK)
 240                         goto err_out;
 241                 if (py_dictitem_as_str(py_entry, "name", &pdch->name) != SRD_OK)
 242                         goto err_out;
 243                 if (py_dictitem_as_str(py_entry, "desc", &pdch->desc) != SRD_OK)
 244                         goto err_out;
 245
 246                 pdch->order = offset + i;
 247         }
 248
 249         Py_DECREF(py_channellist);
 250         *out_pdchl = pdchl;
 251
 252         PyGILState_Release(gstate);
 253
 254         return SRD_OK;
 255
 256 except_out:
 257         srd_exception_catch("Failed to get %s list of %s decoder",
 258                         attr, d->name);
 259
 260 err_out:
 261         g_slist_free_full(pdchl, &channel_free);
 262         Py_XDECREF(py_channellist);
 263         PyGILState_Release(gstate);
 264
 265         return SRD_ERR_PYTHON;
 266 }
 267
 268 static int get_options(struct srd_decoder *d)
 269 {
 270         PyObject *py_opts, *py_opt, *py_str, *py_values, *py_default, *py_item;
 271         GSList *options;
 272         struct srd_decoder_option *o;
 273         GVariant *gvar;
 274         ssize_t opt, i;
 275         PyGILState_STATE gstate;
 276
 277         gstate = PyGILState_Ensure();
 278
 279         if (!PyObject_HasAttrString(d->py_dec, "options")) {
 280                 /* No options, that's fine. */
 281                 PyGILState_Release(gstate);
 282                 return SRD_OK;
 283         }
 284
 285         options = NULL;
 286
 287         /* If present, options must be a tuple. */
 288         py_opts = PyObject_GetAttrString(d->py_dec, "options");
 289         if (!py_opts)
 290                 goto except_out;
 291
 292         if (!PyTuple_Check(py_opts)) {
 293                 srd_err("Protocol decoder %s: options attribute is not "
 294                                 "a tuple.", d->id);
 295                 goto err_out;
 296         }
 297
 298         for (opt = PyTuple_Size(py_opts) - 1; opt >= 0; opt--) {
 299                 py_opt = PyTuple_GetItem(py_opts, opt);
 300                 if (!py_opt)
 301                         goto except_out;
 302
 303                 if (!PyDict_Check(py_opt)) {
 304                         srd_err("Protocol decoder %s options: each option "
 305                                         "must consist of a dictionary.", d->name);
 306                         goto err_out;
 307                 }
 308
 309                 o = g_malloc0(sizeof(struct srd_decoder_option));
 310                 /* Add to list right away so it doesn't get lost. */
 311                 options = g_slist_prepend(options, o);
 312
 313                 py_str = PyDict_GetItemString(py_opt, "id");
 314                 if (!py_str) {
 315                         srd_err("Protocol decoder %s option %zd has no ID.",
 316                                 d->name, opt);
 317                         goto err_out;
 318                 }
 319                 if (py_str_as_str(py_str, &o->id) != SRD_OK)
 320                         goto err_out;
 321
 322                 py_str = PyDict_GetItemString(py_opt, "desc");
 323                 if (py_str) {
 324                         if (py_str_as_str(py_str, &o->desc) != SRD_OK)
 325                                 goto err_out;
 326                 }
 327
 328                 py_default = PyDict_GetItemString(py_opt, "default");
 329                 if (py_default) {
 330                         gvar = py_obj_to_variant(py_default);
 331                         if (!gvar) {
 332                                 srd_err("Protocol decoder %s option 'default' has "
 333                                         "invalid default value.", d->name);
 334                                 goto err_out;
 335                         }
 336                         o->def = g_variant_ref_sink(gvar);
 337                 }
 338
 339                 py_values = PyDict_GetItemString(py_opt, "values");
 340                 if (py_values) {
 341                         /*
 342                          * A default is required if a list of values is
 343                          * given, since it's used to verify their type.
 344                          */
 345                         if (!o->def) {
 346                                 srd_err("No default for option '%s'.", o->id);
 347                                 goto err_out;
 348                         }
 349                         if (!PyTuple_Check(py_values)) {
 350                                 srd_err("Option '%s' values should be a tuple.", o->id);
 351                                 goto err_out;
 352                         }
 353
 354                         for (i = PyTuple_Size(py_values) - 1; i >= 0; i--) {
 355                                 py_item = PyTuple_GetItem(py_values, i);
 356                                 if (!py_item)
 357                                         goto except_out;
 358
 359                                 if (py_default && (Py_TYPE(py_default) != Py_TYPE(py_item))) {
 360                                         srd_err("All values for option '%s' must be "
 361                                                 "of the same type as the default.",
 362                                                 o->id);
 363                                         goto err_out;
 364                                 }
 365                                 gvar = py_obj_to_variant(py_item);
 366                                 if (!gvar) {
 367                                         srd_err("Protocol decoder %s option 'values' "
 368                                                 "contains invalid value.", d->name);
 369                                         goto err_out;
 370                                 }
 371                                 o->values = g_slist_prepend(o->values,
 372                                                 g_variant_ref_sink(gvar));
 373                         }
 374                 }
 375         }
 376         d->options = options;
 377         Py_DECREF(py_opts);
 378         PyGILState_Release(gstate);
 379
 380         return SRD_OK;
 381
 382 except_out:
 383         srd_exception_catch("Failed to get %s decoder options", d->name);
 384
 385 err_out:
 386         g_slist_free_full(options, &decoder_option_free);
 387         Py_XDECREF(py_opts);
 388         PyGILState_Release(gstate);
 389
 390         return SRD_ERR_PYTHON;
 391 }
 392
 393 /* Convert annotation class attribute to GSList of char **. */
 394 static int get_annotations(struct srd_decoder *dec)
 395 {
 396         PyObject *py_annlist, *py_ann;
 397         GSList *annotations;
 398         char **annpair;
 399         ssize_t i;
 400         PyGILState_STATE gstate;
 401
 402         gstate = PyGILState_Ensure();
 403
 404         if (!PyObject_HasAttrString(dec->py_dec, "annotations")) {
 405                 PyGILState_Release(gstate);
 406                 return SRD_OK;
 407         }
 408
 409         annotations = NULL;
 410
 411         py_annlist = PyObject_GetAttrString(dec->py_dec, "annotations");
 412         if (!py_annlist)
 413                 goto except_out;
 414
 415         if (!PyTuple_Check(py_annlist)) {
 416                 srd_err("Protocol decoder %s annotations should be a tuple.",
 417                         dec->name);
 418                 goto err_out;
 419         }
 420
 421         for (i = PyTuple_Size(py_annlist) - 1; i >= 0; i--) {
 422                 py_ann = PyTuple_GetItem(py_annlist, i);
 423                 if (!py_ann)
 424                         goto except_out;
 425
 426                 if (!PyTuple_Check(py_ann) || PyTuple_Size(py_ann) != 2) {
 427                         srd_err("Protocol decoder %s annotation %zd should be a tuple with two elements.",
 428                                 dec->name, i + 1);
 429                         goto err_out;
 430                 }
 431                 if (py_strseq_to_char(py_ann, &annpair) != SRD_OK)
 432                         goto err_out;
 433
 434                 annotations = g_slist_prepend(annotations, annpair);
 435         }
 436         dec->annotations = annotations;
 437         Py_DECREF(py_annlist);
 438         PyGILState_Release(gstate);
 439
 440         return SRD_OK;
 441
 442 except_out:
 443         srd_exception_catch("Failed to get %s decoder annotations", dec->name);
 444
 445 err_out:
 446         g_slist_free_full(annotations, (GDestroyNotify)&g_strfreev);
 447         Py_XDECREF(py_annlist);
 448         PyGILState_Release(gstate);
 449
 450         return SRD_ERR_PYTHON;
 451 }
 452
 453 /* Convert annotation_rows to GSList of 'struct srd_decoder_annotation_row'. */
 454 static int get_annotation_rows(struct srd_decoder *dec)
 455 {
 456         const char *py_member_name = "annotation_rows";
 457
 458         PyObject *py_ann_rows, *py_ann_row, *py_ann_classes, *py_item;
 459         GSList *annotation_rows;
 460         struct srd_decoder_annotation_row *ann_row;
 461         ssize_t i, k;
 462         size_t class_idx;
 463         PyGILState_STATE gstate;
 464
 465         gstate = PyGILState_Ensure();
 466
 467         if (!PyObject_HasAttrString(dec->py_dec, py_member_name)) {
 468                 PyGILState_Release(gstate);
 469                 return SRD_OK;
 470         }
 471
 472         annotation_rows = NULL;
 473
 474         py_ann_rows = PyObject_GetAttrString(dec->py_dec, py_member_name);
 475         if (!py_ann_rows)
 476                 goto except_out;
 477
 478         if (!PyTuple_Check(py_ann_rows)) {
 479                 srd_err("Protocol decoder %s %s must be a tuple.",
 480                         dec->name, py_member_name);
 481                 goto err_out;
 482         }
 483
 484         for (i = PyTuple_Size(py_ann_rows) - 1; i >= 0; i--) {
 485                 py_ann_row = PyTuple_GetItem(py_ann_rows, i);
 486                 if (!py_ann_row)
 487                         goto except_out;
 488
 489                 if (!PyTuple_Check(py_ann_row) || PyTuple_Size(py_ann_row) != 3) {
 490                         srd_err("Protocol decoder %s %s must contain only tuples of 3 elements.",
 491                                 dec->name, py_member_name);
 492                         goto err_out;
 493                 }
 494                 ann_row = g_malloc0(sizeof(struct srd_decoder_annotation_row));
 495                 /* Add to list right away so it doesn't get lost. */
 496                 annotation_rows = g_slist_prepend(annotation_rows, ann_row);
 497
 498                 py_item = PyTuple_GetItem(py_ann_row, 0);
 499                 if (!py_item)
 500                         goto except_out;
 501                 if (py_str_as_str(py_item, &ann_row->id) != SRD_OK)
 502                         goto err_out;
 503
 504                 py_item = PyTuple_GetItem(py_ann_row, 1);
 505                 if (!py_item)
 506                         goto except_out;
 507                 if (py_str_as_str(py_item, &ann_row->desc) != SRD_OK)
 508                         goto err_out;
 509
 510                 py_ann_classes = PyTuple_GetItem(py_ann_row, 2);
 511                 if (!py_ann_classes)
 512                         goto except_out;
 513
 514                 if (!PyTuple_Check(py_ann_classes)) {
 515                         srd_err("Protocol decoder %s %s tuples must have a tuple of numbers as 3rd element.",
 516                                 dec->name, py_member_name);
 517                         goto err_out;
 518                 }
 519
 520                 for (k = PyTuple_Size(py_ann_classes) - 1; k >= 0; k--) {
 521                         py_item = PyTuple_GetItem(py_ann_classes, k);
 522                         if (!py_item)
 523                                 goto except_out;
 524
 525                         if (!PyLong_Check(py_item)) {
 526                                 srd_err("Protocol decoder %s annotation row class tuple must only contain numbers.",
 527                                         dec->name);
 528                                 goto err_out;
 529                         }
 530                         class_idx = PyLong_AsSize_t(py_item);
 531                         if (PyErr_Occurred())
 532                                 goto except_out;
 533
 534                         ann_row->ann_classes = g_slist_prepend(ann_row->ann_classes,
 535                                         GSIZE_TO_POINTER(class_idx));
 536                 }
 537         }
 538         dec->annotation_rows = annotation_rows;
 539         Py_DECREF(py_ann_rows);
 540         PyGILState_Release(gstate);
 541
 542         return SRD_OK;
 543
 544 except_out:
 545         srd_exception_catch("Failed to get %s decoder annotation rows",
 546                         dec->name);
 547
 548 err_out:
 549         g_slist_free_full(annotation_rows, &annotation_row_free);
 550         Py_XDECREF(py_ann_rows);
 551         PyGILState_Release(gstate);
 552
 553         return SRD_ERR_PYTHON;
 554 }
 555
 556 /* Convert binary classes to GSList of char **. */
 557 static int get_binary_classes(struct srd_decoder *dec)
 558 {
 559         PyObject *py_bin_classes, *py_bin_class;
 560         GSList *bin_classes;
 561         char **bin;
 562         ssize_t i;
 563         PyGILState_STATE gstate;
 564
 565         gstate = PyGILState_Ensure();
 566
 567         if (!PyObject_HasAttrString(dec->py_dec, "binary")) {
 568                 PyGILState_Release(gstate);
 569                 return SRD_OK;
 570         }
 571
 572         bin_classes = NULL;
 573
 574         py_bin_classes = PyObject_GetAttrString(dec->py_dec, "binary");
 575         if (!py_bin_classes)
 576                 goto except_out;
 577
 578         if (!PyTuple_Check(py_bin_classes)) {
 579                 srd_err("Protocol decoder %s binary classes should "
 580                         "be a tuple.", dec->name);
 581                 goto err_out;
 582         }
 583
 584         for (i = PyTuple_Size(py_bin_classes) - 1; i >= 0; i--) {
 585                 py_bin_class = PyTuple_GetItem(py_bin_classes, i);
 586                 if (!py_bin_class)
 587                         goto except_out;
 588
 589                 if (!PyTuple_Check(py_bin_class)
 590                                 || PyTuple_Size(py_bin_class) != 2) {
 591                         srd_err("Protocol decoder %s binary classes should "
 592                                 "consist only of tuples of 2 elements.",
 593                                 dec->name);
 594                         goto err_out;
 595                 }
 596                 if (py_strseq_to_char(py_bin_class, &bin) != SRD_OK)
 597                         goto err_out;
 598
 599                 bin_classes = g_slist_prepend(bin_classes, bin);
 600         }
 601         dec->binary = bin_classes;
 602         Py_DECREF(py_bin_classes);
 603         PyGILState_Release(gstate);
 604
 605         return SRD_OK;
 606
 607 except_out:
 608         srd_exception_catch("Failed to get %s decoder binary classes",
 609                         dec->name);
 610
 611 err_out:
 612         g_slist_free_full(bin_classes, (GDestroyNotify)&g_strfreev);
 613         Py_XDECREF(py_bin_classes);
 614         PyGILState_Release(gstate);
 615
 616         return SRD_ERR_PYTHON;
 617 }
 618
 619 /* Convert logic_output_channels to GSList of 'struct srd_decoder_logic_output_channel'. */
 620 static int get_logic_output_channels(struct srd_decoder *dec)
 621 {
 622         PyObject *py_logic_out_chs, *py_logic_out_ch, *py_item;
 623         GSList *logic_out_chs;
 624         struct srd_decoder_logic_output_channel *logic_out_ch;
 625         ssize_t i;
 626         PyGILState_STATE gstate;
 627
 628         gstate = PyGILState_Ensure();
 629
 630         if (!PyObject_HasAttrString(dec->py_dec, "logic_output_channels")) {
 631                 PyGILState_Release(gstate);
 632                 return SRD_OK;
 633         }
 634
 635         logic_out_chs = NULL;
 636
 637         py_logic_out_chs = PyObject_GetAttrString(dec->py_dec, "logic_output_channels");
 638         if (!py_logic_out_chs)
 639                 goto except_out;
 640
 641         if (!PyTuple_Check(py_logic_out_chs)) {
 642                 srd_err("Protocol decoder %s logic_output_channels "
 643                         "must be a tuple.", dec->name);
 644                 goto err_out;
 645         }
 646
 647         for (i = PyTuple_Size(py_logic_out_chs) - 1; i >= 0; i--) {
 648                 py_logic_out_ch = PyTuple_GetItem(py_logic_out_chs, i);
 649                 if (!py_logic_out_ch)
 650                         goto except_out;
 651
 652                 if (!PyTuple_Check(py_logic_out_ch) || PyTuple_Size(py_logic_out_ch) != 2) {
 653                         srd_err("Protocol decoder %s logic_output_channels "
 654                                 "must contain only tuples of 2 elements.",
 655                                 dec->name);
 656                         goto err_out;
 657                 }
 658                 logic_out_ch = g_malloc0(sizeof(*logic_out_ch));
 659                 /* Add to list right away so it doesn't get lost. */
 660                 logic_out_chs = g_slist_prepend(logic_out_chs, logic_out_ch);
 661
 662                 py_item = PyTuple_GetItem(py_logic_out_ch, 0);
 663                 if (!py_item)
 664                         goto except_out;
 665                 if (py_str_as_str(py_item, &logic_out_ch->id) != SRD_OK)
 666                         goto err_out;
 667
 668                 py_item = PyTuple_GetItem(py_logic_out_ch, 1);
 669                 if (!py_item)
 670                         goto except_out;
 671                 if (py_str_as_str(py_item, &logic_out_ch->desc) != SRD_OK)
 672                         goto err_out;
 673         }
 674         dec->logic_output_channels = logic_out_chs;
 675         Py_DECREF(py_logic_out_chs);
 676         PyGILState_Release(gstate);
 677
 678         return SRD_OK;
 679
 680 except_out:
 681         srd_exception_catch("Failed to get %s decoder logic output channels",
 682                         dec->name);
 683
 684 err_out:
 685         g_slist_free_full(logic_out_chs, &logic_output_channel_free);
 686         Py_XDECREF(py_logic_out_chs);
 687         PyGILState_Release(gstate);
 688
 689         return SRD_ERR_PYTHON;
 690 }
 691
 692 /* Check whether the Decoder class defines the named method. */
 693 static int check_method(PyObject *py_dec, const char *mod_name,
 694                 const char *method_name)
 695 {
 696         PyObject *py_method;
 697         int is_callable;
 698         PyGILState_STATE gstate;
 699
 700         gstate = PyGILState_Ensure();
 701
 702         py_method = PyObject_GetAttrString(py_dec, method_name);
 703         if (!py_method) {
 704                 srd_exception_catch("Protocol decoder %s Decoder class "
 705                                 "has no %s() method", mod_name, method_name);
 706                 PyGILState_Release(gstate);
 707                 return SRD_ERR_PYTHON;
 708         }
 709
 710         is_callable = PyCallable_Check(py_method);
 711         Py_DECREF(py_method);
 712
 713         PyGILState_Release(gstate);
 714
 715         if (!is_callable) {
 716                 srd_err("Protocol decoder %s Decoder class attribute '%s' "
 717                         "is not a method.", mod_name, method_name);
 718                 return SRD_ERR_PYTHON;
 719         }
 720
 721         return SRD_OK;
 722 }
 723
 724 /**
 725  * Get the API version of the specified decoder.
 726  *
 727  * @param d The decoder to use. Must not be NULL.
 728  *
 729  * @return The API version of the decoder, or 0 upon errors.
 730  *
 731  * @private
 732  */
 733 SRD_PRIV long srd_decoder_apiver(const struct srd_decoder *d)
 734 {
 735         PyObject *py_apiver;
 736         long apiver;
 737         PyGILState_STATE gstate;
 738
 739         if (!d)
 740                 return 0;
 741
 742         gstate = PyGILState_Ensure();
 743
 744         py_apiver = PyObject_GetAttrString(d->py_dec, "api_version");
 745         apiver = (py_apiver && PyLong_Check(py_apiver))
 746                         ? PyLong_AsLong(py_apiver) : 0;
 747         Py_XDECREF(py_apiver);
 748
 749         PyGILState_Release(gstate);
 750
 751         return apiver;
 752 }
 753
 754 static gboolean contains_duplicates(GSList *list)
 755 {
 756         for (GSList *l1 = list; l1; l1 = l1->next) {
 757                 for (GSList *l2 = l1->next; l2; l2 = l2->next)
 758                         if (!strcmp(l1->data, l2->data))
 759                                 return TRUE;
 760         }
 761
 762         return FALSE;
 763 }
 764
 765 static gboolean contains_duplicate_ids(GSList *list1, GSList *list2)
 766 {
 767         for (GSList *l1 = list1; l1; l1 = l1->next) {
 768                 unsigned int cnt = 0;
 769                 const char **s1 = l1->data;
 770                 for (GSList *l2 = list2; l2; l2 = l2->next) {
 771                         const char **s2 = l2->data;
 772                         if (!strcmp(s1[0], s2[0]))
 773                                 cnt++;
 774                         if ((list1 == list2) && cnt > 1)
 775                                 return TRUE;
 776                         if ((list1 != list2) && cnt > 0)
 777                                 return TRUE;
 778                 }
 779         }
 780
 781         return FALSE;
 782 }
 783
 784 static gboolean contains_duplicate_row_ids(GSList *list1, GSList *list2)
 785 {
 786         for (GSList *l1 = list1; l1; l1 = l1->next) {
 787                 unsigned int cnt = 0;
 788                 const struct srd_decoder_annotation_row *r1 = l1->data;
 789                 for (GSList *l2 = list2; l2; l2 = l2->next) {
 790                         const struct srd_decoder_annotation_row *r2 = l2->data;
 791                         if (!strcmp(r1->id, r2->id))
 792                                 cnt++;
 793                         if (cnt > 1)
 794                                 return TRUE;
 795                 }
 796         }
 797
 798         return FALSE;
 799 }
 800
 801 /**
 802  * Load a protocol decoder module into the embedded Python interpreter.
 803  *
 804  * @param module_name The module name to be loaded.
 805  *
 806  * @return SRD_OK upon success, a (negative) error code otherwise.
 807  *
 808  * @since 0.1.0
 809  */
 810 SRD_API int srd_decoder_load(const char *module_name)
 811 {
 812         PyObject *py_basedec;
 813         struct srd_decoder *d;
 814         long apiver;
 815         int is_subclass;
 816         const char *fail_txt;
 817         PyGILState_STATE gstate;
 818
 819         if (!srd_check_init())
 820                 return SRD_ERR;
 821
 822         if (!module_name)
 823                 return SRD_ERR_ARG;
 824
 825         gstate = PyGILState_Ensure();
 826
 827         if (PyDict_GetItemString(PyImport_GetModuleDict(), module_name)) {
 828                 /* Module was already imported. */
 829                 PyGILState_Release(gstate);
 830                 return SRD_OK;
 831         }
 832
 833         d = g_malloc0(sizeof(struct srd_decoder));
 834         fail_txt = NULL;
 835
 836         d->py_mod = py_import_by_name(module_name);
 837         if (!d->py_mod) {
 838                 fail_txt = "import by name failed";
 839                 goto except_out;
 840         }
 841
 842         if (!mod_sigrokdecode) {
 843                 srd_err("sigrokdecode module not loaded.");
 844                 fail_txt = "sigrokdecode(3) not loaded";
 845                 goto err_out;
 846         }
 847
 848         /* Get the 'Decoder' class as Python object. */
 849         d->py_dec = PyObject_GetAttrString(d->py_mod, "Decoder");
 850         if (!d->py_dec) {
 851                 fail_txt = "no 'Decoder' attribute in imported module";
 852                 goto except_out;
 853         }
 854
 855         py_basedec = PyObject_GetAttrString(mod_sigrokdecode, "Decoder");
 856         if (!py_basedec) {
 857                 fail_txt = "no 'Decoder' attribute in sigrokdecode(3)";
 858                 goto except_out;
 859         }
 860
 861         is_subclass = PyObject_IsSubclass(d->py_dec, py_basedec);
 862         Py_DECREF(py_basedec);
 863
 864         if (!is_subclass) {
 865                 srd_err("Decoder class in protocol decoder module %s is not "
 866                         "a subclass of sigrokdecode.Decoder.", module_name);
 867                 fail_txt = "not a subclass of sigrokdecode.Decoder";
 868                 goto err_out;
 869         }
 870
 871         /*
 872          * Check that this decoder has the correct PD API version.
 873          * PDs of different API versions are incompatible and cannot work.
 874          */
 875         apiver = srd_decoder_apiver(d);
 876         if (apiver != 3) {
 877                 srd_exception_catch("Only PD API version 3 is supported, "
 878                         "decoder %s has version %ld", module_name, apiver);
 879                 fail_txt = "API version mismatch";
 880                 goto err_out;
 881         }
 882
 883         /* Check Decoder class for required methods. */
 884
 885         if (check_method(d->py_dec, module_name, "reset") != SRD_OK) {
 886                 fail_txt = "no 'reset()' method";
 887                 goto err_out;
 888         }
 889
 890         if (check_method(d->py_dec, module_name, "start") != SRD_OK) {
 891                 fail_txt = "no 'start()' method";
 892                 goto err_out;
 893         }
 894
 895         if (check_method(d->py_dec, module_name, "decode") != SRD_OK) {
 896                 fail_txt = "no 'decode()' method";
 897                 goto err_out;
 898         }
 899
 900         /* Store required fields in newly allocated strings. */
 901         if (py_attr_as_str(d->py_dec, "id", &(d->id)) != SRD_OK) {
 902                 fail_txt = "no 'id' attribute";
 903                 goto err_out;
 904         }
 905
 906         if (py_attr_as_str(d->py_dec, "name", &(d->name)) != SRD_OK) {
 907                 fail_txt = "no 'name' attribute";
 908                 goto err_out;
 909         }
 910
 911         if (py_attr_as_str(d->py_dec, "longname", &(d->longname)) != SRD_OK) {
 912                 fail_txt = "no 'longname' attribute";
 913                 goto err_out;
 914         }
 915
 916         if (py_attr_as_str(d->py_dec, "desc", &(d->desc)) != SRD_OK) {
 917                 fail_txt = "no 'desc' attribute";
 918                 goto err_out;
 919         }
 920
 921         if (py_attr_as_str(d->py_dec, "license", &(d->license)) != SRD_OK) {
 922                 fail_txt = "no 'license' attribute";
 923                 goto err_out;
 924         }
 925
 926         if (py_attr_as_strlist(d->py_dec, "inputs", &(d->inputs)) != SRD_OK) {
 927                 fail_txt = "missing or malformed 'inputs' attribute";
 928                 goto err_out;
 929         }
 930
 931         if (py_attr_as_strlist(d->py_dec, "outputs", &(d->outputs)) != SRD_OK) {
 932                 fail_txt = "missing or malformed 'outputs' attribute";
 933                 goto err_out;
 934         }
 935
 936         if (py_attr_as_strlist(d->py_dec, "tags", &(d->tags)) != SRD_OK) {
 937                 fail_txt = "missing or malformed 'tags' attribute";
 938                 goto err_out;
 939         }
 940
 941         /* All options and their default values. */
 942         if (get_options(d) != SRD_OK) {
 943                 fail_txt = "cannot get options";
 944                 goto err_out;
 945         }
 946
 947         /* Check and import required channels. */
 948         if (get_channels(d, "channels", &d->channels, 0) != SRD_OK) {
 949                 fail_txt = "cannot get channels";
 950                 goto err_out;
 951         }
 952
 953         /* Check and import optional channels. */
 954         if (get_channels(d, "optional_channels", &d->opt_channels,
 955                                 g_slist_length(d->channels)) != SRD_OK) {
 956                 fail_txt = "cannot get optional channels";
 957                 goto err_out;
 958         }
 959
 960         if (get_annotations(d) != SRD_OK) {
 961                 fail_txt = "cannot get annotations";
 962                 goto err_out;
 963         }
 964
 965         if (get_annotation_rows(d) != SRD_OK) {
 966                 fail_txt = "cannot get annotation rows";
 967                 goto err_out;
 968         }
 969
 970         if (get_binary_classes(d) != SRD_OK) {
 971                 fail_txt = "cannot get binary classes";
 972                 goto err_out;
 973         }
 974
 975         if (contains_duplicates(d->inputs)) {
 976                 fail_txt = "duplicate input IDs";
 977                 goto err_out;
 978         }
 979
 980         if (contains_duplicates(d->outputs)) {
 981                 fail_txt = "duplicate output IDs";
 982                 goto err_out;
 983         }
 984
 985         if (contains_duplicates(d->tags)) {
 986                 fail_txt = "duplicate tags";
 987                 goto err_out;
 988         }
 989
 990         if (contains_duplicate_ids(d->channels, d->channels)) {
 991                 fail_txt = "duplicate channel IDs";
 992                 goto err_out;
 993         }
 994
 995         if (contains_duplicate_ids(d->opt_channels, d->opt_channels)) {
 996                 fail_txt = "duplicate optional channel IDs";
 997                 goto err_out;
 998         }
 999
1000         if (contains_duplicate_ids(d->channels, d->opt_channels)) {
1001                 fail_txt = "channel and optional channel IDs contain duplicates";
1002                 goto err_out;
1003         }
1004
1005         if (contains_duplicate_ids(d->options, d->options)) {
1006                 fail_txt = "duplicate option IDs";
1007                 goto err_out;
1008         }
1009
1010         if (contains_duplicate_ids(d->annotations, d->annotations)) {
1011                 fail_txt = "duplicate annotation class IDs";
1012                 goto err_out;
1013         }
1014
1015         if (contains_duplicate_row_ids(d->annotation_rows, d->annotation_rows)) {
1016                 fail_txt = "duplicate annotation row IDs";
1017                 goto err_out;
1018         }
1019
1020         if (contains_duplicate_ids(d->annotations, d->annotation_rows)) {
1021                 fail_txt = "annotation class/row IDs contain duplicates";
1022                 goto err_out;
1023         }
1024
1025         if (contains_duplicate_ids(d->binary, d->binary)) {
1026                 fail_txt = "duplicate binary class IDs";
1027                 goto err_out;
1028         }
1029
1030         if (get_logic_output_channels(d) != SRD_OK) {
1031                 fail_txt = "cannot get logic output channels";
1032                 goto err_out;
1033         }
1034
1035         PyGILState_Release(gstate);
1036
1037         /* Append it to the list of loaded decoders. */
1038         pd_list = g_slist_append(pd_list, d);
1039
1040         return SRD_OK;
1041
1042 except_out:
1043         /* Don't show a message for the "common" directory, it's not a PD. */
1044         if (strcmp(module_name, "common")) {
1045                 srd_exception_catch("Failed to load decoder %s: %s",
1046                                     module_name, fail_txt);
1047         }
1048         fail_txt = NULL;
1049
1050 err_out:
1051         if (fail_txt)
1052                 srd_err("Failed to load decoder %s: %s", module_name, fail_txt);
1053         decoder_free(d);
1054         PyGILState_Release(gstate);
1055
1056         return SRD_ERR_PYTHON;
1057 }
1058
1059 /**
1060  * Return a protocol decoder's docstring.
1061  *
1062  * @param dec The loaded protocol decoder. Must not be NULL.
1063  *
1064  * @return A newly allocated buffer containing the protocol decoder's
1065  *         documentation. The caller is responsible for free'ing the buffer.
1066  *
1067  * @since 0.1.0
1068  */
1069 SRD_API char *srd_decoder_doc_get(const struct srd_decoder *dec)
1070 {
1071         PyObject *py_str;
1072         char *doc;
1073         PyGILState_STATE gstate;
1074
1075         if (!srd_check_init())
1076                 return NULL;
1077
1078         if (!dec || !dec->py_mod)
1079                 return NULL;
1080
1081         gstate = PyGILState_Ensure();
1082
1083         if (!PyObject_HasAttrString(dec->py_mod, "__doc__"))
1084                 goto err;
1085
1086         if (!(py_str = PyObject_GetAttrString(dec->py_mod, "__doc__"))) {
1087                 srd_exception_catch("Failed to get docstring");
1088                 goto err;
1089         }
1090
1091         doc = NULL;
1092         if (py_str != Py_None)
1093                 py_str_as_str(py_str, &doc);
1094         Py_DECREF(py_str);
1095
1096         PyGILState_Release(gstate);
1097
1098         return doc;
1099
1100 err:
1101         PyGILState_Release(gstate);
1102
1103         return NULL;
1104 }
1105
1106 /**
1107  * Unload the specified protocol decoder.
1108  *
1109  * @param dec The struct srd_decoder to be unloaded.
1110  *
1111  * @return SRD_OK upon success, a (negative) error code otherwise.
1112  *
1113  * @since 0.1.0
1114  */
1115 SRD_API int srd_decoder_unload(struct srd_decoder *dec)
1116 {
1117         struct srd_session *sess;
1118         GSList *l;
1119
1120         if (!srd_check_init())
1121                 return SRD_ERR;
1122
1123         if (!dec)
1124                 return SRD_ERR_ARG;
1125
1126         /*
1127          * Since any instances of this decoder need to be released as well,
1128          * but they could be anywhere in the stack, just free the entire
1129          * stack. A frontend reloading a decoder thus has to restart all
1130          * instances, and rebuild the stack.
1131          */
1132         for (l = sessions; l; l = l->next) {
1133                 sess = l->data;
1134                 srd_inst_free_all(sess);
1135         }
1136
1137         /* Remove the PD from the list of loaded decoders. */
1138         pd_list = g_slist_remove(pd_list, dec);
1139
1140         decoder_free(dec);
1141
1142         return SRD_OK;
1143 }
1144
1145 static void srd_decoder_load_all_zip_path(char *zip_path)
1146 {
1147         PyObject *zipimport_mod, *zipimporter_class, *zipimporter;
1148         PyObject *prefix_obj, *files, *key, *value, *set, *modname;
1149         Py_ssize_t pos = 0;
1150         char *prefix;
1151         size_t prefix_len;
1152         PyGILState_STATE gstate;
1153
1154         set = files = prefix_obj = zipimporter = zipimporter_class = NULL;
1155
1156         gstate = PyGILState_Ensure();
1157
1158         zipimport_mod = py_import_by_name("zipimport");
1159         if (zipimport_mod == NULL)
1160                 goto err_out;
1161
1162         zipimporter_class = PyObject_GetAttrString(zipimport_mod, "zipimporter");
1163         if (zipimporter_class == NULL)
1164                 goto err_out;
1165
1166         zipimporter = PyObject_CallFunction(zipimporter_class, "s", zip_path);
1167         if (zipimporter == NULL)
1168                 goto err_out;
1169
1170         prefix_obj = PyObject_GetAttrString(zipimporter, "prefix");
1171         if (prefix_obj == NULL)
1172                 goto err_out;
1173
1174         files = PyObject_GetAttrString(zipimporter, "_files");
1175         if (files == NULL || !PyDict_Check(files))
1176                 goto err_out;
1177
1178         set = PySet_New(NULL);
1179         if (set == NULL)
1180                 goto err_out;
1181
1182         if (py_str_as_str(prefix_obj, &prefix) != SRD_OK)
1183                 goto err_out;
1184
1185         prefix_len = strlen(prefix);
1186
1187         while (PyDict_Next(files, &pos, &key, &value)) {
1188                 char *path, *slash;
1189                 if (py_str_as_str(key, &path) == SRD_OK) {
1190                         if (strlen(path) > prefix_len
1191                                         && memcmp(path, prefix, prefix_len) == 0
1192                                         && (slash = strchr(path + prefix_len, '/'))) {
1193
1194                                 modname = PyUnicode_FromStringAndSize(path + prefix_len,
1195                                                         slash - (path + prefix_len));
1196                                 if (modname == NULL) {
1197                                         PyErr_Clear();
1198                                 } else {
1199                                         PySet_Add(set, modname);
1200                                         Py_DECREF(modname);
1201                                 }
1202                         }
1203                         g_free(path);
1204                 }
1205         }
1206         g_free(prefix);
1207
1208         while ((modname = PySet_Pop(set))) {
1209                 char *modname_str;
1210                 if (py_str_as_str(modname, &modname_str) == SRD_OK) {
1211                         /* The directory name is the module name (e.g. "i2c"). */
1212                         srd_decoder_load(modname_str);
1213                         g_free(modname_str);
1214                 }
1215                 Py_DECREF(modname);
1216         }
1217
1218 err_out:
1219         Py_XDECREF(set);
1220         Py_XDECREF(files);
1221         Py_XDECREF(prefix_obj);
1222         Py_XDECREF(zipimporter);
1223         Py_XDECREF(zipimporter_class);
1224         Py_XDECREF(zipimport_mod);
1225         PyErr_Clear();
1226         PyGILState_Release(gstate);
1227 }
1228
1229 static void srd_decoder_load_all_path(char *path)
1230 {
1231         GDir *dir;
1232         const gchar *direntry;
1233
1234         if (!(dir = g_dir_open(path, 0, NULL))) {
1235                 /* Not really fatal. Try zipimport method too. */
1236                 srd_decoder_load_all_zip_path(path);
1237                 return;
1238         }
1239
1240         /*
1241          * This ignores errors returned by srd_decoder_load(). That
1242          * function will have logged the cause, but in any case we
1243          * want to continue anyway.
1244          */
1245         while ((direntry = g_dir_read_name(dir)) != NULL) {
1246                 /* The directory name is the module name (e.g. "i2c"). */
1247                 srd_decoder_load(direntry);
1248         }
1249         g_dir_close(dir);
1250 }
1251
1252 /**
1253  * Load all installed protocol decoders.
1254  *
1255  * @return SRD_OK upon success, a (negative) error code otherwise.
1256  *
1257  * @since 0.1.0
1258  */
1259 SRD_API int srd_decoder_load_all(void)
1260 {
1261         GSList *l;
1262
1263         if (!srd_check_init())
1264                 return SRD_ERR;
1265
1266         for (l = searchpaths; l; l = l->next)
1267                 srd_decoder_load_all_path(l->data);
1268
1269         return SRD_OK;
1270 }
1271
1272 static void srd_decoder_unload_cb(void *arg, void *ignored)
1273 {
1274         (void)ignored;
1275
1276         srd_decoder_unload((struct srd_decoder *)arg);
1277 }
1278
1279 /**
1280  * Unload all loaded protocol decoders.
1281  *
1282  * @return SRD_OK upon success, a (negative) error code otherwise.
1283  *
1284  * @since 0.1.0
1285  */
1286 SRD_API int srd_decoder_unload_all(void)
1287 {
1288         g_slist_foreach(pd_list, srd_decoder_unload_cb, NULL);
1289         g_slist_free(pd_list);
1290         pd_list = NULL;
1291
1292         return SRD_OK;
1293 }
1294
1295 /** @} */