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, size_t *ret_count)
 395 {
 396         PyObject *py_annlist, *py_ann;
 397         GSList *annotations;
 398         char **annpair;
 399         ssize_t i;
 400         PyGILState_STATE gstate;
 401
 402         if (ret_count)
 403                 *ret_count = 0;
 404
 405         gstate = PyGILState_Ensure();
 406
 407         if (!PyObject_HasAttrString(dec->py_dec, "annotations")) {
 408                 PyGILState_Release(gstate);
 409                 return SRD_OK;
 410         }
 411
 412         annotations = NULL;
 413
 414         py_annlist = PyObject_GetAttrString(dec->py_dec, "annotations");
 415         if (!py_annlist)
 416                 goto except_out;
 417
 418         if (!PyTuple_Check(py_annlist)) {
 419                 srd_err("Protocol decoder %s annotations should be a tuple.",
 420                         dec->name);
 421                 goto err_out;
 422         }
 423
 424         i = PyTuple_Size(py_annlist);
 425         if (ret_count)
 426                 *ret_count = i;
 427         while (i--) {
 428                 py_ann = PyTuple_GetItem(py_annlist, i);
 429                 if (!py_ann)
 430                         goto except_out;
 431
 432                 if (!PyTuple_Check(py_ann) || PyTuple_Size(py_ann) != 2) {
 433                         srd_err("Protocol decoder %s annotation %zd should be a tuple with two elements.",
 434                                 dec->name, i + 1);
 435                         goto err_out;
 436                 }
 437                 if (py_strseq_to_char(py_ann, &annpair) != SRD_OK)
 438                         goto err_out;
 439
 440                 annotations = g_slist_prepend(annotations, annpair);
 441         }
 442         dec->annotations = annotations;
 443         Py_DECREF(py_annlist);
 444         PyGILState_Release(gstate);
 445
 446         return SRD_OK;
 447
 448 except_out:
 449         srd_exception_catch("Failed to get %s decoder annotations", dec->name);
 450
 451 err_out:
 452         g_slist_free_full(annotations, (GDestroyNotify)&g_strfreev);
 453         Py_XDECREF(py_annlist);
 454         PyGILState_Release(gstate);
 455
 456         return SRD_ERR_PYTHON;
 457 }
 458
 459 /* Convert annotation_rows to GSList of 'struct srd_decoder_annotation_row'. */
 460 static int get_annotation_rows(struct srd_decoder *dec, size_t cls_count)
 461 {
 462         const char *py_member_name = "annotation_rows";
 463
 464         PyObject *py_ann_rows, *py_ann_row, *py_ann_classes, *py_item;
 465         GSList *annotation_rows;
 466         struct srd_decoder_annotation_row *ann_row;
 467         ssize_t i, k;
 468         size_t class_idx;
 469         PyGILState_STATE gstate;
 470
 471         gstate = PyGILState_Ensure();
 472
 473         if (!PyObject_HasAttrString(dec->py_dec, py_member_name)) {
 474                 PyGILState_Release(gstate);
 475                 return SRD_OK;
 476         }
 477
 478         annotation_rows = NULL;
 479
 480         py_ann_rows = PyObject_GetAttrString(dec->py_dec, py_member_name);
 481         if (!py_ann_rows)
 482                 goto except_out;
 483
 484         if (!PyTuple_Check(py_ann_rows)) {
 485                 srd_err("Protocol decoder %s %s must be a tuple.",
 486                         dec->name, py_member_name);
 487                 goto err_out;
 488         }
 489
 490         for (i = PyTuple_Size(py_ann_rows) - 1; i >= 0; i--) {
 491                 py_ann_row = PyTuple_GetItem(py_ann_rows, i);
 492                 if (!py_ann_row)
 493                         goto except_out;
 494
 495                 if (!PyTuple_Check(py_ann_row) || PyTuple_Size(py_ann_row) != 3) {
 496                         srd_err("Protocol decoder %s %s must contain only tuples of 3 elements.",
 497                                 dec->name, py_member_name);
 498                         goto err_out;
 499                 }
 500                 ann_row = g_malloc0(sizeof(struct srd_decoder_annotation_row));
 501                 /* Add to list right away so it doesn't get lost. */
 502                 annotation_rows = g_slist_prepend(annotation_rows, ann_row);
 503
 504                 py_item = PyTuple_GetItem(py_ann_row, 0);
 505                 if (!py_item)
 506                         goto except_out;
 507                 if (py_str_as_str(py_item, &ann_row->id) != SRD_OK)
 508                         goto err_out;
 509
 510                 py_item = PyTuple_GetItem(py_ann_row, 1);
 511                 if (!py_item)
 512                         goto except_out;
 513                 if (py_str_as_str(py_item, &ann_row->desc) != SRD_OK)
 514                         goto err_out;
 515
 516                 py_ann_classes = PyTuple_GetItem(py_ann_row, 2);
 517                 if (!py_ann_classes)
 518                         goto except_out;
 519
 520                 if (!PyTuple_Check(py_ann_classes)) {
 521                         srd_err("Protocol decoder %s %s tuples must have a tuple of numbers as 3rd element.",
 522                                 dec->name, py_member_name);
 523                         goto err_out;
 524                 }
 525
 526                 for (k = PyTuple_Size(py_ann_classes) - 1; k >= 0; k--) {
 527                         py_item = PyTuple_GetItem(py_ann_classes, k);
 528                         if (!py_item)
 529                                 goto except_out;
 530
 531                         if (!PyLong_Check(py_item)) {
 532                                 srd_err("Protocol decoder %s annotation row class tuple must only contain numbers.",
 533                                         dec->name);
 534                                 goto err_out;
 535                         }
 536                         class_idx = PyLong_AsSize_t(py_item);
 537                         if (PyErr_Occurred())
 538                                 goto except_out;
 539                         if (class_idx >= cls_count) {
 540                                 srd_err("Protocol decoder %s annotation row %zd references invalid class %zu.",
 541                                         dec->name, i, class_idx);
 542                                 goto err_out;
 543                         }
 544
 545                         ann_row->ann_classes = g_slist_prepend(ann_row->ann_classes,
 546                                         GSIZE_TO_POINTER(class_idx));
 547                 }
 548         }
 549         dec->annotation_rows = annotation_rows;
 550         Py_DECREF(py_ann_rows);
 551         PyGILState_Release(gstate);
 552
 553         return SRD_OK;
 554
 555 except_out:
 556         srd_exception_catch("Failed to get %s decoder annotation rows",
 557                         dec->name);
 558
 559 err_out:
 560         g_slist_free_full(annotation_rows, &annotation_row_free);
 561         Py_XDECREF(py_ann_rows);
 562         PyGILState_Release(gstate);
 563
 564         return SRD_ERR_PYTHON;
 565 }
 566
 567 /* Convert binary classes to GSList of char **. */
 568 static int get_binary_classes(struct srd_decoder *dec)
 569 {
 570         PyObject *py_bin_classes, *py_bin_class;
 571         GSList *bin_classes;
 572         char **bin;
 573         ssize_t i;
 574         PyGILState_STATE gstate;
 575
 576         gstate = PyGILState_Ensure();
 577
 578         if (!PyObject_HasAttrString(dec->py_dec, "binary")) {
 579                 PyGILState_Release(gstate);
 580                 return SRD_OK;
 581         }
 582
 583         bin_classes = NULL;
 584
 585         py_bin_classes = PyObject_GetAttrString(dec->py_dec, "binary");
 586         if (!py_bin_classes)
 587                 goto except_out;
 588
 589         if (!PyTuple_Check(py_bin_classes)) {
 590                 srd_err("Protocol decoder %s binary classes should "
 591                         "be a tuple.", dec->name);
 592                 goto err_out;
 593         }
 594
 595         for (i = PyTuple_Size(py_bin_classes) - 1; i >= 0; i--) {
 596                 py_bin_class = PyTuple_GetItem(py_bin_classes, i);
 597                 if (!py_bin_class)
 598                         goto except_out;
 599
 600                 if (!PyTuple_Check(py_bin_class)
 601                                 || PyTuple_Size(py_bin_class) != 2) {
 602                         srd_err("Protocol decoder %s binary classes should "
 603                                 "consist only of tuples of 2 elements.",
 604                                 dec->name);
 605                         goto err_out;
 606                 }
 607                 if (py_strseq_to_char(py_bin_class, &bin) != SRD_OK)
 608                         goto err_out;
 609
 610                 bin_classes = g_slist_prepend(bin_classes, bin);
 611         }
 612         dec->binary = bin_classes;
 613         Py_DECREF(py_bin_classes);
 614         PyGILState_Release(gstate);
 615
 616         return SRD_OK;
 617
 618 except_out:
 619         srd_exception_catch("Failed to get %s decoder binary classes",
 620                         dec->name);
 621
 622 err_out:
 623         g_slist_free_full(bin_classes, (GDestroyNotify)&g_strfreev);
 624         Py_XDECREF(py_bin_classes);
 625         PyGILState_Release(gstate);
 626
 627         return SRD_ERR_PYTHON;
 628 }
 629
 630 /* Convert logic_output_channels to GSList of 'struct srd_decoder_logic_output_channel'. */
 631 static int get_logic_output_channels(struct srd_decoder *dec)
 632 {
 633         PyObject *py_logic_out_chs, *py_logic_out_ch, *py_item;
 634         GSList *logic_out_chs;
 635         struct srd_decoder_logic_output_channel *logic_out_ch;
 636         ssize_t i;
 637         PyGILState_STATE gstate;
 638
 639         gstate = PyGILState_Ensure();
 640
 641         if (!PyObject_HasAttrString(dec->py_dec, "logic_output_channels")) {
 642                 PyGILState_Release(gstate);
 643                 return SRD_OK;
 644         }
 645
 646         logic_out_chs = NULL;
 647
 648         py_logic_out_chs = PyObject_GetAttrString(dec->py_dec, "logic_output_channels");
 649         if (!py_logic_out_chs)
 650                 goto except_out;
 651
 652         if (!PyTuple_Check(py_logic_out_chs)) {
 653                 srd_err("Protocol decoder %s logic_output_channels "
 654                         "must be a tuple.", dec->name);
 655                 goto err_out;
 656         }
 657
 658         for (i = PyTuple_Size(py_logic_out_chs) - 1; i >= 0; i--) {
 659                 py_logic_out_ch = PyTuple_GetItem(py_logic_out_chs, i);
 660                 if (!py_logic_out_ch)
 661                         goto except_out;
 662
 663                 if (!PyTuple_Check(py_logic_out_ch) || PyTuple_Size(py_logic_out_ch) != 2) {
 664                         srd_err("Protocol decoder %s logic_output_channels "
 665                                 "must contain only tuples of 2 elements.",
 666                                 dec->name);
 667                         goto err_out;
 668                 }
 669                 logic_out_ch = g_malloc0(sizeof(*logic_out_ch));
 670                 /* Add to list right away so it doesn't get lost. */
 671                 logic_out_chs = g_slist_prepend(logic_out_chs, logic_out_ch);
 672
 673                 py_item = PyTuple_GetItem(py_logic_out_ch, 0);
 674                 if (!py_item)
 675                         goto except_out;
 676                 if (py_str_as_str(py_item, &logic_out_ch->id) != SRD_OK)
 677                         goto err_out;
 678
 679                 py_item = PyTuple_GetItem(py_logic_out_ch, 1);
 680                 if (!py_item)
 681                         goto except_out;
 682                 if (py_str_as_str(py_item, &logic_out_ch->desc) != SRD_OK)
 683                         goto err_out;
 684         }
 685         dec->logic_output_channels = logic_out_chs;
 686         Py_DECREF(py_logic_out_chs);
 687         PyGILState_Release(gstate);
 688
 689         return SRD_OK;
 690
 691 except_out:
 692         srd_exception_catch("Failed to get %s decoder logic output channels",
 693                         dec->name);
 694
 695 err_out:
 696         g_slist_free_full(logic_out_chs, &logic_output_channel_free);
 697         Py_XDECREF(py_logic_out_chs);
 698         PyGILState_Release(gstate);
 699
 700         return SRD_ERR_PYTHON;
 701 }
 702
 703 /* Check whether the Decoder class defines the named method. */
 704 static int check_method(PyObject *py_dec, const char *mod_name,
 705                 const char *method_name)
 706 {
 707         PyObject *py_method;
 708         int is_callable;
 709         PyGILState_STATE gstate;
 710
 711         gstate = PyGILState_Ensure();
 712
 713         py_method = PyObject_GetAttrString(py_dec, method_name);
 714         if (!py_method) {
 715                 srd_exception_catch("Protocol decoder %s Decoder class "
 716                                 "has no %s() method", mod_name, method_name);
 717                 PyGILState_Release(gstate);
 718                 return SRD_ERR_PYTHON;
 719         }
 720
 721         is_callable = PyCallable_Check(py_method);
 722         Py_DECREF(py_method);
 723
 724         PyGILState_Release(gstate);
 725
 726         if (!is_callable) {
 727                 srd_err("Protocol decoder %s Decoder class attribute '%s' "
 728                         "is not a method.", mod_name, method_name);
 729                 return SRD_ERR_PYTHON;
 730         }
 731
 732         return SRD_OK;
 733 }
 734
 735 /**
 736  * Get the API version of the specified decoder.
 737  *
 738  * @param d The decoder to use. Must not be NULL.
 739  *
 740  * @return The API version of the decoder, or 0 upon errors.
 741  *
 742  * @private
 743  */
 744 SRD_PRIV long srd_decoder_apiver(const struct srd_decoder *d)
 745 {
 746         PyObject *py_apiver;
 747         long apiver;
 748         PyGILState_STATE gstate;
 749
 750         if (!d)
 751                 return 0;
 752
 753         gstate = PyGILState_Ensure();
 754
 755         py_apiver = PyObject_GetAttrString(d->py_dec, "api_version");
 756         apiver = (py_apiver && PyLong_Check(py_apiver))
 757                         ? PyLong_AsLong(py_apiver) : 0;
 758         Py_XDECREF(py_apiver);
 759
 760         PyGILState_Release(gstate);
 761
 762         return apiver;
 763 }
 764
 765 static gboolean contains_duplicates(GSList *list)
 766 {
 767         for (GSList *l1 = list; l1; l1 = l1->next) {
 768                 for (GSList *l2 = l1->next; l2; l2 = l2->next)
 769                         if (!strcmp(l1->data, l2->data))
 770                                 return TRUE;
 771         }
 772
 773         return FALSE;
 774 }
 775
 776 static gboolean contains_duplicate_ids(GSList *list1, GSList *list2)
 777 {
 778         for (GSList *l1 = list1; l1; l1 = l1->next) {
 779                 unsigned int cnt = 0;
 780                 const char **s1 = l1->data;
 781                 for (GSList *l2 = list2; l2; l2 = l2->next) {
 782                         const char **s2 = l2->data;
 783                         if (!strcmp(s1[0], s2[0]))
 784                                 cnt++;
 785                         if ((list1 == list2) && cnt > 1)
 786                                 return TRUE;
 787                         if ((list1 != list2) && cnt > 0)
 788                                 return TRUE;
 789                 }
 790         }
 791
 792         return FALSE;
 793 }
 794
 795 static gboolean contains_duplicate_row_ids(GSList *list1, GSList *list2)
 796 {
 797         for (GSList *l1 = list1; l1; l1 = l1->next) {
 798                 unsigned int cnt = 0;
 799                 const struct srd_decoder_annotation_row *r1 = l1->data;
 800                 for (GSList *l2 = list2; l2; l2 = l2->next) {
 801                         const struct srd_decoder_annotation_row *r2 = l2->data;
 802                         if (!strcmp(r1->id, r2->id))
 803                                 cnt++;
 804                         if (cnt > 1)
 805                                 return TRUE;
 806                 }
 807         }
 808
 809         return FALSE;
 810 }
 811
 812 /**
 813  * Load a protocol decoder module into the embedded Python interpreter.
 814  *
 815  * @param module_name The module name to be loaded.
 816  *
 817  * @return SRD_OK upon success, a (negative) error code otherwise.
 818  *
 819  * @since 0.1.0
 820  */
 821 SRD_API int srd_decoder_load(const char *module_name)
 822 {
 823         PyObject *py_basedec;
 824         struct srd_decoder *d;
 825         long apiver;
 826         int is_subclass;
 827         const char *fail_txt;
 828         PyGILState_STATE gstate;
 829         size_t ann_cls_count;
 830
 831         if (!srd_check_init())
 832                 return SRD_ERR;
 833
 834         if (!module_name)
 835                 return SRD_ERR_ARG;
 836
 837         gstate = PyGILState_Ensure();
 838
 839         if (PyDict_GetItemString(PyImport_GetModuleDict(), module_name)) {
 840                 /* Module was already imported. */
 841                 PyGILState_Release(gstate);
 842                 return SRD_OK;
 843         }
 844
 845         d = g_malloc0(sizeof(struct srd_decoder));
 846         fail_txt = NULL;
 847
 848         d->py_mod = py_import_by_name(module_name);
 849         if (!d->py_mod) {
 850                 fail_txt = "import by name failed";
 851                 goto except_out;
 852         }
 853
 854         if (!mod_sigrokdecode) {
 855                 srd_err("sigrokdecode module not loaded.");
 856                 fail_txt = "sigrokdecode(3) not loaded";
 857                 goto err_out;
 858         }
 859
 860         /* Get the 'Decoder' class as Python object. */
 861         d->py_dec = PyObject_GetAttrString(d->py_mod, "Decoder");
 862         if (!d->py_dec) {
 863                 fail_txt = "no 'Decoder' attribute in imported module";
 864                 goto except_out;
 865         }
 866
 867         py_basedec = PyObject_GetAttrString(mod_sigrokdecode, "Decoder");
 868         if (!py_basedec) {
 869                 fail_txt = "no 'Decoder' attribute in sigrokdecode(3)";
 870                 goto except_out;
 871         }
 872
 873         is_subclass = PyObject_IsSubclass(d->py_dec, py_basedec);
 874         Py_DECREF(py_basedec);
 875
 876         if (!is_subclass) {
 877                 srd_err("Decoder class in protocol decoder module %s is not "
 878                         "a subclass of sigrokdecode.Decoder.", module_name);
 879                 fail_txt = "not a subclass of sigrokdecode.Decoder";
 880                 goto err_out;
 881         }
 882
 883         /*
 884          * Check that this decoder has the correct PD API version.
 885          * PDs of different API versions are incompatible and cannot work.
 886          */
 887         apiver = srd_decoder_apiver(d);
 888         if (apiver != 3) {
 889                 srd_exception_catch("Only PD API version 3 is supported, "
 890                         "decoder %s has version %ld", module_name, apiver);
 891                 fail_txt = "API version mismatch";
 892                 goto err_out;
 893         }
 894
 895         /* Check Decoder class for required methods. */
 896
 897         if (check_method(d->py_dec, module_name, "reset") != SRD_OK) {
 898                 fail_txt = "no 'reset()' method";
 899                 goto err_out;
 900         }
 901
 902         if (check_method(d->py_dec, module_name, "start") != SRD_OK) {
 903                 fail_txt = "no 'start()' method";
 904                 goto err_out;
 905         }
 906
 907         if (check_method(d->py_dec, module_name, "decode") != SRD_OK) {
 908                 fail_txt = "no 'decode()' method";
 909                 goto err_out;
 910         }
 911
 912         /* Store required fields in newly allocated strings. */
 913         if (py_attr_as_str(d->py_dec, "id", &(d->id)) != SRD_OK) {
 914                 fail_txt = "no 'id' attribute";
 915                 goto err_out;
 916         }
 917
 918         if (py_attr_as_str(d->py_dec, "name", &(d->name)) != SRD_OK) {
 919                 fail_txt = "no 'name' attribute";
 920                 goto err_out;
 921         }
 922
 923         if (py_attr_as_str(d->py_dec, "longname", &(d->longname)) != SRD_OK) {
 924                 fail_txt = "no 'longname' attribute";
 925                 goto err_out;
 926         }
 927
 928         if (py_attr_as_str(d->py_dec, "desc", &(d->desc)) != SRD_OK) {
 929                 fail_txt = "no 'desc' attribute";
 930                 goto err_out;
 931         }
 932
 933         if (py_attr_as_str(d->py_dec, "license", &(d->license)) != SRD_OK) {
 934                 fail_txt = "no 'license' attribute";
 935                 goto err_out;
 936         }
 937
 938         if (py_attr_as_strlist(d->py_dec, "inputs", &(d->inputs)) != SRD_OK) {
 939                 fail_txt = "missing or malformed 'inputs' attribute";
 940                 goto err_out;
 941         }
 942
 943         if (py_attr_as_strlist(d->py_dec, "outputs", &(d->outputs)) != SRD_OK) {
 944                 fail_txt = "missing or malformed 'outputs' attribute";
 945                 goto err_out;
 946         }
 947
 948         if (py_attr_as_strlist(d->py_dec, "tags", &(d->tags)) != SRD_OK) {
 949                 fail_txt = "missing or malformed 'tags' attribute";
 950                 goto err_out;
 951         }
 952
 953         /* All options and their default values. */
 954         if (get_options(d) != SRD_OK) {
 955                 fail_txt = "cannot get options";
 956                 goto err_out;
 957         }
 958
 959         /* Check and import required channels. */
 960         if (get_channels(d, "channels", &d->channels, 0) != SRD_OK) {
 961                 fail_txt = "cannot get channels";
 962                 goto err_out;
 963         }
 964
 965         /* Check and import optional channels. */
 966         if (get_channels(d, "optional_channels", &d->opt_channels,
 967                                 g_slist_length(d->channels)) != SRD_OK) {
 968                 fail_txt = "cannot get optional channels";
 969                 goto err_out;
 970         }
 971
 972         if (get_annotations(d, &ann_cls_count) != SRD_OK) {
 973                 fail_txt = "cannot get annotations";
 974                 goto err_out;
 975         }
 976
 977         if (get_annotation_rows(d, ann_cls_count) != SRD_OK) {
 978                 fail_txt = "cannot get annotation rows";
 979                 goto err_out;
 980         }
 981
 982         if (get_binary_classes(d) != SRD_OK) {
 983                 fail_txt = "cannot get binary classes";
 984                 goto err_out;
 985         }
 986
 987         if (contains_duplicates(d->inputs)) {
 988                 fail_txt = "duplicate input IDs";
 989                 goto err_out;
 990         }
 991
 992         if (contains_duplicates(d->outputs)) {
 993                 fail_txt = "duplicate output IDs";
 994                 goto err_out;
 995         }
 996
 997         if (contains_duplicates(d->tags)) {
 998                 fail_txt = "duplicate tags";
 999                 goto err_out;
1000         }
1001
1002         if (contains_duplicate_ids(d->channels, d->channels)) {
1003                 fail_txt = "duplicate channel IDs";
1004                 goto err_out;
1005         }
1006
1007         if (contains_duplicate_ids(d->opt_channels, d->opt_channels)) {
1008                 fail_txt = "duplicate optional channel IDs";
1009                 goto err_out;
1010         }
1011
1012         if (contains_duplicate_ids(d->channels, d->opt_channels)) {
1013                 fail_txt = "channel and optional channel IDs contain duplicates";
1014                 goto err_out;
1015         }
1016
1017         if (contains_duplicate_ids(d->options, d->options)) {
1018                 fail_txt = "duplicate option IDs";
1019                 goto err_out;
1020         }
1021
1022         if (contains_duplicate_ids(d->annotations, d->annotations)) {
1023                 fail_txt = "duplicate annotation class IDs";
1024                 goto err_out;
1025         }
1026
1027         if (contains_duplicate_row_ids(d->annotation_rows, d->annotation_rows)) {
1028                 fail_txt = "duplicate annotation row IDs";
1029                 goto err_out;
1030         }
1031
1032         if (contains_duplicate_ids(d->annotations, d->annotation_rows)) {
1033                 fail_txt = "annotation class/row IDs contain duplicates";
1034                 goto err_out;
1035         }
1036
1037         if (contains_duplicate_ids(d->binary, d->binary)) {
1038                 fail_txt = "duplicate binary class IDs";
1039                 goto err_out;
1040         }
1041
1042         if (get_logic_output_channels(d) != SRD_OK) {
1043                 fail_txt = "cannot get logic output channels";
1044                 goto err_out;
1045         }
1046
1047         PyGILState_Release(gstate);
1048
1049         /* Append it to the list of loaded decoders. */
1050         pd_list = g_slist_append(pd_list, d);
1051
1052         return SRD_OK;
1053
1054 except_out:
1055         /* Don't show a message for the "common" directory, it's not a PD. */
1056         if (strcmp(module_name, "common")) {
1057                 srd_exception_catch("Failed to load decoder %s: %s",
1058                                     module_name, fail_txt);
1059         }
1060         fail_txt = NULL;
1061
1062 err_out:
1063         if (fail_txt)
1064                 srd_err("Failed to load decoder %s: %s", module_name, fail_txt);
1065         decoder_free(d);
1066         PyGILState_Release(gstate);
1067
1068         return SRD_ERR_PYTHON;
1069 }
1070
1071 /**
1072  * Return a protocol decoder's docstring.
1073  *
1074  * @param dec The loaded protocol decoder. Must not be NULL.
1075  *
1076  * @return A newly allocated buffer containing the protocol decoder's
1077  *         documentation. The caller is responsible for free'ing the buffer.
1078  *
1079  * @since 0.1.0
1080  */
1081 SRD_API char *srd_decoder_doc_get(const struct srd_decoder *dec)
1082 {
1083         PyObject *py_str;
1084         char *doc;
1085         PyGILState_STATE gstate;
1086
1087         if (!srd_check_init())
1088                 return NULL;
1089
1090         if (!dec || !dec->py_mod)
1091                 return NULL;
1092
1093         gstate = PyGILState_Ensure();
1094
1095         if (!PyObject_HasAttrString(dec->py_mod, "__doc__"))
1096                 goto err;
1097
1098         if (!(py_str = PyObject_GetAttrString(dec->py_mod, "__doc__"))) {
1099                 srd_exception_catch("Failed to get docstring");
1100                 goto err;
1101         }
1102
1103         doc = NULL;
1104         if (py_str != Py_None)
1105                 py_str_as_str(py_str, &doc);
1106         Py_DECREF(py_str);
1107
1108         PyGILState_Release(gstate);
1109
1110         return doc;
1111
1112 err:
1113         PyGILState_Release(gstate);
1114
1115         return NULL;
1116 }
1117
1118 /**
1119  * Unload the specified protocol decoder.
1120  *
1121  * @param dec The struct srd_decoder to be unloaded.
1122  *
1123  * @return SRD_OK upon success, a (negative) error code otherwise.
1124  *
1125  * @since 0.1.0
1126  */
1127 SRD_API int srd_decoder_unload(struct srd_decoder *dec)
1128 {
1129         struct srd_session *sess;
1130         GSList *l;
1131
1132         if (!srd_check_init())
1133                 return SRD_ERR;
1134
1135         if (!dec)
1136                 return SRD_ERR_ARG;
1137
1138         /*
1139          * Since any instances of this decoder need to be released as well,
1140          * but they could be anywhere in the stack, just free the entire
1141          * stack. A frontend reloading a decoder thus has to restart all
1142          * instances, and rebuild the stack.
1143          */
1144         for (l = sessions; l; l = l->next) {
1145                 sess = l->data;
1146                 srd_inst_free_all(sess);
1147         }
1148
1149         /* Remove the PD from the list of loaded decoders. */
1150         pd_list = g_slist_remove(pd_list, dec);
1151
1152         decoder_free(dec);
1153
1154         return SRD_OK;
1155 }
1156
1157 static void srd_decoder_load_all_zip_path(char *zip_path)
1158 {
1159         PyObject *zipimport_mod, *zipimporter_class, *zipimporter;
1160         PyObject *prefix_obj, *files, *key, *value, *set, *modname;
1161         Py_ssize_t pos = 0;
1162         char *prefix;
1163         size_t prefix_len;
1164         PyGILState_STATE gstate;
1165
1166         set = files = prefix_obj = zipimporter = zipimporter_class = NULL;
1167
1168         gstate = PyGILState_Ensure();
1169
1170         zipimport_mod = py_import_by_name("zipimport");
1171         if (zipimport_mod == NULL)
1172                 goto err_out;
1173
1174         zipimporter_class = PyObject_GetAttrString(zipimport_mod, "zipimporter");
1175         if (zipimporter_class == NULL)
1176                 goto err_out;
1177
1178         zipimporter = PyObject_CallFunction(zipimporter_class, "s", zip_path);
1179         if (zipimporter == NULL)
1180                 goto err_out;
1181
1182         prefix_obj = PyObject_GetAttrString(zipimporter, "prefix");
1183         if (prefix_obj == NULL)
1184                 goto err_out;
1185
1186         files = PyObject_GetAttrString(zipimporter, "_files");
1187         if (files == NULL || !PyDict_Check(files))
1188                 goto err_out;
1189
1190         set = PySet_New(NULL);
1191         if (set == NULL)
1192                 goto err_out;
1193
1194         if (py_str_as_str(prefix_obj, &prefix) != SRD_OK)
1195                 goto err_out;
1196
1197         prefix_len = strlen(prefix);
1198
1199         while (PyDict_Next(files, &pos, &key, &value)) {
1200                 char *path, *slash;
1201                 if (py_str_as_str(key, &path) == SRD_OK) {
1202                         if (strlen(path) > prefix_len
1203                                         && memcmp(path, prefix, prefix_len) == 0
1204                                         && (slash = strchr(path + prefix_len, '/'))) {
1205
1206                                 modname = PyUnicode_FromStringAndSize(path + prefix_len,
1207                                                         slash - (path + prefix_len));
1208                                 if (modname == NULL) {
1209                                         PyErr_Clear();
1210                                 } else {
1211                                         PySet_Add(set, modname);
1212                                         Py_DECREF(modname);
1213                                 }
1214                         }
1215                         g_free(path);
1216                 }
1217         }
1218         g_free(prefix);
1219
1220         while ((modname = PySet_Pop(set))) {
1221                 char *modname_str;
1222                 if (py_str_as_str(modname, &modname_str) == SRD_OK) {
1223                         /* The directory name is the module name (e.g. "i2c"). */
1224                         srd_decoder_load(modname_str);
1225                         g_free(modname_str);
1226                 }
1227                 Py_DECREF(modname);
1228         }
1229
1230 err_out:
1231         Py_XDECREF(set);
1232         Py_XDECREF(files);
1233         Py_XDECREF(prefix_obj);
1234         Py_XDECREF(zipimporter);
1235         Py_XDECREF(zipimporter_class);
1236         Py_XDECREF(zipimport_mod);
1237         PyErr_Clear();
1238         PyGILState_Release(gstate);
1239 }
1240
1241 static void srd_decoder_load_all_path(char *path)
1242 {
1243         GDir *dir;
1244         const gchar *direntry;
1245
1246         if (!(dir = g_dir_open(path, 0, NULL))) {
1247                 /* Not really fatal. Try zipimport method too. */
1248                 srd_decoder_load_all_zip_path(path);
1249                 return;
1250         }
1251
1252         /*
1253          * This ignores errors returned by srd_decoder_load(). That
1254          * function will have logged the cause, but in any case we
1255          * want to continue anyway.
1256          */
1257         while ((direntry = g_dir_read_name(dir)) != NULL) {
1258                 /* The directory name is the module name (e.g. "i2c"). */
1259                 srd_decoder_load(direntry);
1260         }
1261         g_dir_close(dir);
1262 }
1263
1264 /**
1265  * Load all installed protocol decoders.
1266  *
1267  * @return SRD_OK upon success, a (negative) error code otherwise.
1268  *
1269  * @since 0.1.0
1270  */
1271 SRD_API int srd_decoder_load_all(void)
1272 {
1273         GSList *l;
1274
1275         if (!srd_check_init())
1276                 return SRD_ERR;
1277
1278         for (l = searchpaths; l; l = l->next)
1279                 srd_decoder_load_all_path(l->data);
1280
1281         return SRD_OK;
1282 }
1283
1284 static void srd_decoder_unload_cb(void *arg, void *ignored)
1285 {
1286         (void)ignored;
1287
1288         srd_decoder_unload((struct srd_decoder *)arg);
1289 }
1290
1291 /**
1292  * Unload all loaded protocol decoders.
1293  *
1294  * @return SRD_OK upon success, a (negative) error code otherwise.
1295  *
1296  * @since 0.1.0
1297  */
1298 SRD_API int srd_decoder_unload_all(void)
1299 {
1300         g_slist_foreach(pd_list, srd_decoder_unload_cb, NULL);
1301         g_slist_free(pd_list);
1302         pd_list = NULL;
1303
1304         return SRD_OK;
1305 }
1306
1307 /** @} */