libsigrokdecode
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controller.c
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1 /*
2  * This file is part of the sigrok 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 "sigrokdecode.h" /* First, so we avoid a _POSIX_C_SOURCE warning. */
22 #include "sigrokdecode-internal.h"
23 #include "config.h"
24 #include <glib.h>
25 #include <inttypes.h>
26 #include <stdlib.h>
27 
28 /* List of decoder instances. */
29 static GSList *di_list = NULL;
30 
31 /* List of frontend callbacks to receive decoder output. */
32 static GSList *callbacks = NULL;
33 
34 /* decoder.c */
35 extern SRD_PRIV GSList *pd_list;
36 
37 /* module_sigrokdecode.c */
38 /* FIXME: SRD_PRIV causes issues on MinGW. Investigate. */
39 extern PyMODINIT_FUNC PyInit_sigrokdecode(void);
40 
41 /* type_logic.c */
42 extern SRD_PRIV PyTypeObject srd_logic_type;
43 
44 /**
45  * Initialize libsigrokdecode.
46  *
47  * This initializes the Python interpreter, and creates and initializes
48  * a "sigrokdecode" Python module.
49  *
50  * Then, it searches for sigrok protocol decoder files (*.py) in the
51  * "decoders" subdirectory of the the sigrok installation directory.
52  * All decoders that are found are loaded into memory and added to an
53  * internal list of decoders, which can be queried via srd_decoders_list().
54  *
55  * The caller is responsible for calling the clean-up function srd_exit(),
56  * which will properly shut down libsigrokdecode and free its allocated memory.
57  *
58  * Multiple calls to srd_init(), without calling srd_exit() in between,
59  * are not allowed.
60  *
61  * @param path Path to an extra directory containing protocol decoders
62  * which will be added to the Python sys.path, or NULL.
63  *
64  * @return SRD_OK upon success, a (negative) error code otherwise.
65  * Upon Python errors, return SRD_ERR_PYTHON. If the sigrok decoders
66  * directory cannot be accessed, return SRD_ERR_DECODERS_DIR.
67  * If not enough memory could be allocated, return SRD_ERR_MALLOC.
68  */
69 SRD_API int srd_init(const char *path)
70 {
71  int ret;
72  char *env_path;
73 
74  srd_dbg("Initializing libsigrokdecode.");
75 
76  /* Add our own module to the list of built-in modules. */
77  PyImport_AppendInittab("sigrokdecode", PyInit_sigrokdecode);
78 
79  /* Initialize the Python interpreter. */
80  Py_Initialize();
81 
82  /* Installed decoders. */
83  if ((ret = srd_decoder_searchpath_add(DECODERS_DIR)) != SRD_OK) {
84  Py_Finalize();
85  return ret;
86  }
87 
88  /* Path specified by the user. */
89  if (path) {
90  if ((ret = srd_decoder_searchpath_add(path)) != SRD_OK) {
91  Py_Finalize();
92  return ret;
93  }
94  }
95 
96  /* Environment variable overrides everything, for debugging. */
97  if ((env_path = getenv("SIGROKDECODE_DIR"))) {
98  if ((ret = srd_decoder_searchpath_add(env_path)) != SRD_OK) {
99  Py_Finalize();
100  return ret;
101  }
102  }
103 
104  return SRD_OK;
105 }
106 
107 /**
108  * Shutdown libsigrokdecode.
109  *
110  * This frees all the memory allocated for protocol decoders and shuts down
111  * the Python interpreter.
112  *
113  * This function should only be called if there was a (successful!) invocation
114  * of srd_init() before. Calling this function multiple times in a row, without
115  * any successful srd_init() calls in between, is not allowed.
116  *
117  * @return SRD_OK upon success, a (negative) error code otherwise.
118  */
119 SRD_API int srd_exit(void)
120 {
121  srd_dbg("Exiting libsigrokdecode.");
122 
124  g_slist_free(pd_list);
125  pd_list = NULL;
126 
127  /* Py_Finalize() returns void, any finalization errors are ignored. */
128  Py_Finalize();
129 
130  return SRD_OK;
131 }
132 
133 /**
134  * Add an additional search directory for the protocol decoders.
135  *
136  * The specified directory is prepended (not appended!) to Python's sys.path,
137  * in order to search for sigrok protocol decoders in the specified
138  * directories first, and in the generic Python module directories (and in
139  * the current working directory) last. This avoids conflicts if there are
140  * Python modules which have the same name as a sigrok protocol decoder in
141  * sys.path or in the current working directory.
142  *
143  * @param path Path to the directory containing protocol decoders which shall
144  * be added to the Python sys.path, or NULL.
145  *
146  * @return SRD_OK upon success, a (negative) error code otherwise.
147  */
149 {
150  PyObject *py_cur_path, *py_item;
151  GString *new_path;
152  int wc_len, i;
153  wchar_t *wc_new_path;
154  char *item;
155 
156  srd_dbg("Adding '%s' to module path.", path);
157 
158  new_path = g_string_sized_new(256);
159  g_string_assign(new_path, g_strdup(path));
160  py_cur_path = PySys_GetObject("path");
161  for (i = 0; i < PyList_Size(py_cur_path); i++) {
162  g_string_append(new_path, g_strdup(G_SEARCHPATH_SEPARATOR_S));
163  py_item = PyList_GetItem(py_cur_path, i);
164  if (!PyUnicode_Check(py_item))
165  /* Shouldn't happen. */
166  continue;
167  if (py_str_as_str(py_item, &item) != SRD_OK)
168  continue;
169  g_string_append(new_path, item);
170  }
171 
172  /* Convert to wide chars. */
173  wc_len = sizeof(wchar_t) * (new_path->len + 1);
174  if (!(wc_new_path = g_try_malloc(wc_len))) {
175  srd_dbg("malloc failed");
176  return SRD_ERR_MALLOC;
177  }
178  mbstowcs(wc_new_path, new_path->str, wc_len);
179  PySys_SetPath(wc_new_path);
180  g_string_free(new_path, TRUE);
181  g_free(wc_new_path);
182 
183 //#ifdef _WIN32
184 // gchar **splitted;
185 //
186 // /*
187 // * On Windows/MinGW, Python's sys.path needs entries of the form
188 // * 'C:\\foo\\bar' instead of '/foo/bar'.
189 // */
190 //
191 // splitted = g_strsplit(DECODERS_DIR, "/", 0);
192 // path = g_build_pathv("\\\\", splitted);
193 // g_strfreev(splitted);
194 //#else
195 // path = g_strdup(DECODERS_DIR);
196 //#endif
197 
198  return SRD_OK;
199 }
200 
201 /**
202  * Set one or more options in a decoder instance.
203  *
204  * Handled options are removed from the hash.
205  *
206  * @param di Decoder instance.
207  * @param options A GHashTable of options to set.
208  *
209  * @return SRD_OK upon success, a (negative) error code otherwise.
210  */
212  GHashTable *options)
213 {
214  PyObject *py_dec_options, *py_dec_optkeys, *py_di_options, *py_optval;
215  PyObject *py_optlist, *py_classval;
216  Py_UNICODE *py_ustr;
217  unsigned long long int val_ull;
218  int num_optkeys, ret, size, i;
219  char *key, *value;
220 
221  if (!PyObject_HasAttrString(di->decoder->py_dec, "options")) {
222  /* Decoder has no options. */
223  if (g_hash_table_size(options) == 0) {
224  /* No options provided. */
225  return SRD_OK;
226  } else {
227  srd_err("Protocol decoder has no options.");
228  return SRD_ERR_ARG;
229  }
230  return SRD_OK;
231  }
232 
233  ret = SRD_ERR_PYTHON;
234  key = NULL;
235  py_dec_options = py_dec_optkeys = py_di_options = py_optval = NULL;
236  py_optlist = py_classval = NULL;
237  py_dec_options = PyObject_GetAttrString(di->decoder->py_dec, "options");
238 
239  /* All of these are synthesized objects, so they're good. */
240  py_dec_optkeys = PyDict_Keys(py_dec_options);
241  num_optkeys = PyList_Size(py_dec_optkeys);
242  if (!(py_di_options = PyObject_GetAttrString(di->py_inst, "options")))
243  goto err_out;
244  for (i = 0; i < num_optkeys; i++) {
245  /* Get the default class value for this option. */
246  py_str_as_str(PyList_GetItem(py_dec_optkeys, i), &key);
247  if (!(py_optlist = PyDict_GetItemString(py_dec_options, key)))
248  goto err_out;
249  if (!(py_classval = PyList_GetItem(py_optlist, 1)))
250  goto err_out;
251  if (!PyUnicode_Check(py_classval) && !PyLong_Check(py_classval)) {
252  srd_err("Options of type %s are not yet supported.",
253  Py_TYPE(py_classval)->tp_name);
254  goto err_out;
255  }
256 
257  if ((value = g_hash_table_lookup(options, key))) {
258  /* An override for this option was provided. */
259  if (PyUnicode_Check(py_classval)) {
260  if (!(py_optval = PyUnicode_FromString(value))) {
261  /* Some UTF-8 encoding error. */
262  PyErr_Clear();
263  goto err_out;
264  }
265  } else if (PyLong_Check(py_classval)) {
266  if (!(py_optval = PyLong_FromString(value, NULL, 0))) {
267  /* ValueError Exception */
268  PyErr_Clear();
269  srd_err("Option %s has invalid value "
270  "%s: expected integer.",
271  key, value);
272  goto err_out;
273  }
274  }
275  g_hash_table_remove(options, key);
276  } else {
277  /* Use the class default for this option. */
278  if (PyUnicode_Check(py_classval)) {
279  /* Make a brand new copy of the string. */
280  py_ustr = PyUnicode_AS_UNICODE(py_classval);
281  size = PyUnicode_GET_SIZE(py_classval);
282  py_optval = PyUnicode_FromUnicode(py_ustr, size);
283  } else if (PyLong_Check(py_classval)) {
284  /* Make a brand new copy of the integer. */
285  val_ull = PyLong_AsUnsignedLongLong(py_classval);
286  if (val_ull == (unsigned long long)-1) {
287  /* OverFlowError exception */
288  PyErr_Clear();
289  srd_err("Invalid integer value for %s: "
290  "expected integer.", key);
291  goto err_out;
292  }
293  if (!(py_optval = PyLong_FromUnsignedLongLong(val_ull)))
294  goto err_out;
295  }
296  }
297 
298  /*
299  * If we got here, py_optval holds a known good new reference
300  * to the instance option to set.
301  */
302  if (PyDict_SetItemString(py_di_options, key, py_optval) == -1)
303  goto err_out;
304  }
305 
306  ret = SRD_OK;
307 
308 err_out:
309  Py_XDECREF(py_optlist);
310  Py_XDECREF(py_di_options);
311  Py_XDECREF(py_dec_optkeys);
312  Py_XDECREF(py_dec_options);
313  g_free(key);
314  if (PyErr_Occurred())
315  srd_exception_catch("Stray exception in srd_inst_option_set().");
316 
317  return ret;
318 }
319 
320 /* Helper GComparefunc for g_slist_find_custom() in srd_inst_probe_set_all() */
321 static gint compare_probe_id(const struct srd_probe *a, const char *probe_id)
322 {
323  return strcmp(a->id, probe_id);
324 }
325 
326 /**
327  * Set all probes in a decoder instance.
328  *
329  * This function sets _all_ probes for the specified decoder instance, i.e.,
330  * it overwrites any probes that were already defined (if any).
331  *
332  * @param di Decoder instance.
333  * @param probes A GHashTable of probes to set. Key is probe name, value is
334  * the probe number. Samples passed to this instance will be
335  * arranged in this order.
336  *
337  * @return SRD_OK upon success, a (negative) error code otherwise.
338  */
340  GHashTable *new_probes)
341 {
342  GList *l;
343  GSList *sl;
344  struct srd_probe *p;
345  int *new_probemap, new_probenum;
346  char *probe_id, *probenum_str;
347 
348  srd_dbg("set probes called for instance %s with list of %d probes",
349  di->inst_id, g_hash_table_size(new_probes));
350 
351  if (g_hash_table_size(new_probes) == 0)
352  /* No probes provided. */
353  return SRD_OK;
354 
355  if (di->dec_num_probes == 0) {
356  /* Decoder has no probes. */
357  srd_err("Protocol decoder %s has no probes to define.",
358  di->decoder->name);
359  return SRD_ERR_ARG;
360  }
361 
362  new_probemap = NULL;
363 
364  if (!(new_probemap = g_try_malloc(sizeof(int) * di->dec_num_probes))) {
365  srd_err("Failed to g_malloc() new probe map.");
366  return SRD_ERR_MALLOC;
367  }
368 
369  for (l = g_hash_table_get_keys(new_probes); l; l = l->next) {
370  probe_id = l->data;
371  probenum_str = g_hash_table_lookup(new_probes, probe_id);
372  if (!probenum_str) {
373  /* Probe name was specified without a value. */
374  srd_err("No probe number was specified for %s.",
375  probe_id);
376  g_free(new_probemap);
377  return SRD_ERR_ARG;
378  }
379  new_probenum = strtol(probenum_str, NULL, 10);
380  if (!(sl = g_slist_find_custom(di->decoder->probes, probe_id,
381  (GCompareFunc)compare_probe_id))) {
382  /* Fall back on optional probes. */
383  if (!(sl = g_slist_find_custom(di->decoder->opt_probes,
384  probe_id, (GCompareFunc) compare_probe_id))) {
385  srd_err("Protocol decoder %s has no probe "
386  "'%s'.", di->decoder->name, probe_id);
387  g_free(new_probemap);
388  return SRD_ERR_ARG;
389  }
390  }
391  p = sl->data;
392  new_probemap[p->order] = new_probenum;
393  srd_dbg("setting probe mapping for %d = probe %d", p->order,
394  new_probenum);
395  }
396  g_free(di->dec_probemap);
397  di->dec_probemap = new_probemap;
398 
399  return SRD_OK;
400 }
401 
402 /**
403  * Create a new protocol decoder instance.
404  *
405  * @param id Decoder 'id' field.
406  * @param options GHashtable of options which override the defaults set in
407  * the decoder class.
408  *
409  * @return Pointer to a newly allocated struct srd_decoder_inst, or
410  * NULL in case of failure.
411  */
412 SRD_API struct srd_decoder_inst *srd_inst_new(const char *decoder_id,
413  GHashTable *options)
414 {
415  int i;
416  struct srd_decoder *dec;
417  struct srd_decoder_inst *di;
418  char *inst_id;
419 
420  srd_dbg("Creating new %s instance.", decoder_id);
421 
422  if (!(dec = srd_decoder_get_by_id(decoder_id))) {
423  srd_err("Protocol decoder %s not found.", decoder_id);
424  return NULL;
425  }
426 
427  if (!(di = g_try_malloc0(sizeof(struct srd_decoder_inst)))) {
428  srd_err("Failed to g_malloc() instance.");
429  return NULL;
430  }
431 
432  inst_id = g_hash_table_lookup(options, "id");
433  di->decoder = dec;
434  di->inst_id = g_strdup(inst_id ? inst_id : decoder_id);
435  g_hash_table_remove(options, "id");
436 
437  /*
438  * Prepare a default probe map, where samples come in the
439  * order in which the decoder class defined them.
440  */
441  di->dec_num_probes = g_slist_length(di->decoder->probes) +
442  g_slist_length(di->decoder->opt_probes);
443  if (di->dec_num_probes) {
444  if (!(di->dec_probemap =
445  g_try_malloc(sizeof(int) * di->dec_num_probes))) {
446  srd_err("Failed to g_malloc() probe map.");
447  g_free(di);
448  return NULL;
449  }
450  for (i = 0; i < di->dec_num_probes; i++)
451  di->dec_probemap[i] = i;
452  }
453 
454  /* Create a new instance of this decoder class. */
455  if (!(di->py_inst = PyObject_CallObject(dec->py_dec, NULL))) {
456  if (PyErr_Occurred())
457  srd_exception_catch("failed to create %s instance: ",
458  decoder_id);
459  g_free(di->dec_probemap);
460  g_free(di);
461  return NULL;
462  }
463 
464  if (srd_inst_option_set(di, options) != SRD_OK) {
465  g_free(di->dec_probemap);
466  g_free(di);
467  return NULL;
468  }
469 
470  /* Instance takes input from a frontend by default. */
471  di_list = g_slist_append(di_list, di);
472 
473  return di;
474 }
475 
476 /**
477  * Stack a decoder instance on top of another.
478  *
479  * @param di_from The instance to move.
480  * @param di_to The instance on top of which di_from will be stacked.
481  *
482  * @return SRD_OK upon success, a (negative) error code otherwise.
483  */
485  struct srd_decoder_inst *di_to)
486 {
487  if (!di_from || !di_to) {
488  srd_err("Invalid from/to instance pair.");
489  return SRD_ERR_ARG;
490  }
491 
492  if (g_slist_find(di_list, di_to)) {
493  /* Remove from the unstacked list. */
494  di_list = g_slist_remove(di_list, di_to);
495  }
496 
497  /* Stack on top of source di. */
498  di_from->next_di = g_slist_append(di_from->next_di, di_to);
499 
500  return SRD_OK;
501 }
502 
503 /**
504  * Find a decoder instance by its instance ID.
505  *
506  * Only the bottom level of instances are searched -- instances already stacked
507  * on top of another one will not be found.
508  *
509  * @param inst_id The instance ID to be found.
510  *
511  * @return Pointer to struct srd_decoder_inst, or NULL if not found.
512  */
514 {
515  GSList *l;
516  struct srd_decoder_inst *tmp, *di;
517 
518  di = NULL;
519  for (l = di_list; l; l = l->next) {
520  tmp = l->data;
521  if (!strcmp(tmp->inst_id, inst_id)) {
522  di = tmp;
523  break;
524  }
525  }
526 
527  return di;
528 }
529 
530 /**
531  * Find a decoder instance by its Python object.
532  *
533  * I.e. find that instance's instantiation of the sigrokdecode.Decoder class.
534  * This will recurse to find the instance anywhere in the stack tree.
535  *
536  * @param stack Pointer to a GSList of struct srd_decoder_inst, indicating the
537  * stack to search. To start searching at the bottom level of
538  * decoder instances, pass NULL.
539  * @param obj The Python class instantiation.
540  *
541  * @return Pointer to struct srd_decoder_inst, or NULL if not found.
542  */
543 SRD_PRIV struct srd_decoder_inst *srd_inst_find_by_obj(const GSList *stack,
544  const PyObject *obj)
545 {
546 // TODO?
547  const GSList *l;
548  struct srd_decoder_inst *tmp, *di;
549 
550  di = NULL;
551  for (l = stack ? stack : di_list; di == NULL && l != NULL; l = l->next) {
552  tmp = l->data;
553  if (tmp->py_inst == obj)
554  di = tmp;
555  else if (tmp->next_di)
556  di = srd_inst_find_by_obj(tmp->next_di, obj);
557  }
558 
559  return di;
560 }
561 
562 SRD_PRIV int srd_inst_start(struct srd_decoder_inst *di, PyObject *args)
563 {
564  PyObject *py_name, *py_res;
565  GSList *l;
566  struct srd_decoder_inst *next_di;
567 
568  srd_dbg("Calling start() method on protocol decoder instance %s.",
569  di->inst_id);
570 
571  if (!(py_name = PyUnicode_FromString("start"))) {
572  srd_err("Unable to build Python object for 'start'.");
573  srd_exception_catch("Protocol decoder instance %s: ",
574  di->inst_id);
575  return SRD_ERR_PYTHON;
576  }
577 
578  if (!(py_res = PyObject_CallMethodObjArgs(di->py_inst,
579  py_name, args, NULL))) {
580  srd_exception_catch("Protocol decoder instance %s: ",
581  di->inst_id);
582  return SRD_ERR_PYTHON;
583  }
584 
585  Py_DecRef(py_res);
586  Py_DecRef(py_name);
587 
588  /*
589  * Start all the PDs stacked on top of this one. Pass along the
590  * metadata all the way from the bottom PD, even though it's only
591  * applicable to logic data for now.
592  */
593  for (l = di->next_di; l; l = l->next) {
594  next_di = l->data;
595  srd_inst_start(next_di, args);
596  }
597 
598  return SRD_OK;
599 }
600 
601 /**
602  * Run the specified decoder function.
603  *
604  * @param start_samplenum The starting sample number for the buffer's sample
605  * set, relative to the start of capture.
606  * @param di The decoder instance to call. Must not be NULL.
607  * @param inbuf The buffer to decode. Must not be NULL.
608  * @param inbuflen Length of the buffer. Must be > 0.
609  *
610  * @return SRD_OK upon success, a (negative) error code otherwise.
611  */
612 SRD_PRIV int srd_inst_decode(uint64_t start_samplenum,
613  const struct srd_decoder_inst *di,
614  const uint8_t *inbuf, uint64_t inbuflen)
615 {
616  PyObject *py_res;
617  srd_logic *logic;
618  uint64_t end_samplenum;
619 
620  srd_dbg("Calling decode() on instance %s with %d bytes starting "
621  "at sample %d.", di->inst_id, inbuflen, start_samplenum);
622 
623  /* Return an error upon unusable input. */
624  if (!di) {
625  srd_dbg("empty decoder instance");
626  return SRD_ERR_ARG;
627  }
628  if (!inbuf) {
629  srd_dbg("NULL buffer pointer");
630  return SRD_ERR_ARG;
631  }
632  if (inbuflen == 0) {
633  srd_dbg("empty buffer");
634  return SRD_ERR_ARG;
635  }
636 
637  /*
638  * Create new srd_logic object. Each iteration around the PD's loop
639  * will fill one sample into this object.
640  */
641  logic = PyObject_New(srd_logic, &srd_logic_type);
642  Py_INCREF(logic);
643  logic->di = (struct srd_decoder_inst *)di;
644  logic->start_samplenum = start_samplenum;
645  logic->itercnt = 0;
646  logic->inbuf = (uint8_t *)inbuf;
647  logic->inbuflen = inbuflen;
648  logic->sample = PyList_New(2);
649  Py_INCREF(logic->sample);
650 
651  Py_IncRef(di->py_inst);
652  end_samplenum = start_samplenum + inbuflen / di->data_unitsize;
653  if (!(py_res = PyObject_CallMethod(di->py_inst, "decode",
654  "KKO", logic->start_samplenum,
655  end_samplenum, logic))) {
656  srd_exception_catch("Protocol decoder instance %s: ",
657  di->inst_id);
658  return SRD_ERR_PYTHON; /* TODO: More specific error? */
659  }
660  Py_DecRef(py_res);
661 
662  return SRD_OK;
663 }
664 
666 {
667  GSList *l;
668  struct srd_pd_output *pdo;
669 
670  srd_dbg("Freeing instance %s", di->inst_id);
671 
672  Py_DecRef(di->py_inst);
673  g_free(di->inst_id);
674  g_free(di->dec_probemap);
675  g_slist_free(di->next_di);
676  for (l = di->pd_output; l; l = l->next) {
677  pdo = l->data;
678  g_free(pdo->proto_id);
679  g_free(pdo);
680  }
681  g_slist_free(di->pd_output);
682 }
683 
684 SRD_PRIV void srd_inst_free_all(GSList *stack)
685 {
686  GSList *l;
687  struct srd_decoder_inst *di;
688 
689  di = NULL;
690  for (l = stack ? stack : di_list; di == NULL && l != NULL; l = l->next) {
691  di = l->data;
692  if (di->next_di)
694  srd_inst_free(di);
695  }
696  if (!stack) {
697  g_slist_free(di_list);
698  di_list = NULL;
699  }
700 }
701 
702 /**
703  * Start a decoding session.
704  *
705  * Decoders, instances and stack must have been prepared beforehand.
706  *
707  * @param num_probes The number of probes which the incoming feed will contain.
708  * @param unitsize The number of bytes per sample in the incoming feed.
709  * @param samplerate The samplerate of the incoming feed.
710  *
711  * @return SRD_OK upon success, a (negative) error code otherwise.
712  */
713 SRD_API int srd_session_start(int num_probes, int unitsize, uint64_t samplerate)
714 {
715  PyObject *args;
716  GSList *d;
717  struct srd_decoder_inst *di;
718  int ret;
719 
720  srd_dbg("Calling start() on all instances with %d probes, "
721  "unitsize %d samplerate %d.", num_probes, unitsize, samplerate);
722 
723  /*
724  * Currently only one item of metadata is passed along to decoders,
725  * samplerate. This can be extended as needed.
726  */
727  if (!(args = Py_BuildValue("{s:l}", "samplerate", (long)samplerate))) {
728  srd_err("Unable to build Python object for metadata.");
729  return SRD_ERR_PYTHON;
730  }
731 
732  /* Run the start() method on all decoders receiving frontend data. */
733  for (d = di_list; d; d = d->next) {
734  di = d->data;
735  di->data_num_probes = num_probes;
736  di->data_unitsize = unitsize;
737  di->data_samplerate = samplerate;
738  if ((ret = srd_inst_start(di, args) != SRD_OK))
739  break;
740  }
741 
742  Py_DecRef(args);
743 
744  return ret;
745 }
746 
747 /**
748  * Send a chunk of logic sample data to a running decoder session.
749  *
750  * @param start_samplenum The sample number of the first sample in this chunk.
751  * @param inbuf Pointer to sample data.
752  * @param inbuf Length in bytes of the buffer.
753  *
754  * @return SRD_OK upon success, a (negative) error code otherwise.
755  */
756 SRD_API int srd_session_send(uint64_t start_samplenum, const uint8_t *inbuf,
757  uint64_t inbuflen)
758 {
759  GSList *d;
760  int ret;
761 
762  srd_dbg("Calling decode() on all instances with starting sample "
763  "number %" PRIu64 ", %" PRIu64 " bytes at 0x%p",
764  start_samplenum, inbuflen, inbuf);
765 
766  for (d = di_list; d; d = d->next) {
767  if ((ret = srd_inst_decode(start_samplenum, d->data, inbuf,
768  inbuflen)) != SRD_OK)
769  return ret;
770  }
771 
772  return SRD_OK;
773 }
774 
775 /**
776  * Register/add a decoder output callback function.
777  *
778  * The function will be called when a protocol decoder sends output back
779  * to the PD controller (except for Python objects, which only go up the
780  * stack).
781  *
782  * @param output_type The output type this callback will receive. Only one
783  * callback per output type can be registered.
784  * @param cb The function to call. Must not be NULL.
785  * @param cb_data Private data for the callback function. Can be NULL.
786  */
788  srd_pd_output_callback_t cb, void *cb_data)
789 {
790  struct srd_pd_callback *pd_cb;
791 
792  srd_dbg("Registering new callback for output type %d.", output_type);
793 
794  if (!(pd_cb = g_try_malloc(sizeof(struct srd_pd_callback)))) {
795  srd_err("Failed to g_malloc() struct srd_pd_callback.");
796  return SRD_ERR_MALLOC;
797  }
798 
799  pd_cb->output_type = output_type;
800  pd_cb->cb = cb;
801  pd_cb->cb_data = cb_data;
802  callbacks = g_slist_append(callbacks, pd_cb);
803 
804  return SRD_OK;
805 }
806 
808 {
809  GSList *l;
810  struct srd_pd_callback *pd_cb;
811  void *(cb);
812 
813  cb = NULL;
814  for (l = callbacks; l; l = l->next) {
815  pd_cb = l->data;
816  if (pd_cb->output_type == output_type) {
817  cb = pd_cb->cb;
818  break;
819  }
820  }
821 
822  return cb;
823 }
824 
825 /* This is the backend function to Python sigrokdecode.add() call. */
827  int output_type, const char *proto_id)
828 {
829  struct srd_pd_output *pdo;
830 
831  srd_dbg("Instance %s creating new output type %d for %s.",
832  di->inst_id, output_type, proto_id);
833 
834  if (!(pdo = g_try_malloc(sizeof(struct srd_pd_output)))) {
835  srd_err("Failed to g_malloc() struct srd_pd_output.");
836  return -1;
837  }
838 
839  /* pdo_id is just a simple index, nothing is deleted from this list anyway. */
840  pdo->pdo_id = g_slist_length(di->pd_output);
841  pdo->output_type = output_type;
842  pdo->di = di;
843  pdo->proto_id = g_strdup(proto_id);
844  di->pd_output = g_slist_append(di->pd_output, pdo);
845 
846  return pdo->pdo_id;
847 }