2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
5 * gstcaps.c: Element capabilities subsystem
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library 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 GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
23 /* #define GST_DEBUG_ENABLED */
24 #include "gst_private.h"
29 #include "gstpropsprivate.h"
31 static GMemChunk *_gst_caps_chunk;
32 static GMutex *_gst_caps_chunk_lock;
35 _gst_caps_initialize (void)
37 _gst_caps_chunk = g_mem_chunk_new ("GstCaps",
38 sizeof (GstCaps), sizeof (GstCaps) * 256,
40 _gst_caps_chunk_lock = g_mutex_new ();
44 get_type_for_mime (const gchar *mime)
48 typeid = gst_type_find_by_mime (mime);
50 GstTypeDefinition definition;
51 GstTypeFactory *factory;
53 definition.name = "capstype";
54 definition.mime = g_strdup (mime);
55 definition.exts = NULL;
56 definition.typefindfunc = NULL;
58 factory = gst_typefactory_new (&definition);
60 typeid = gst_type_register (factory);
67 * @name: the name of this capability
68 * @mime: the mime type to attach to the capability
69 * @props: the properties to add to this capability
71 * Create a new capability with the given mime typei and properties.
73 * Returns: a new capability
76 gst_caps_new (const gchar *name, const gchar *mime, GstProps *props)
78 g_return_val_if_fail (mime != NULL, NULL);
80 return gst_caps_new_id (name, get_type_for_mime (mime), props);
85 * @name: the name of this capability
86 * @id: the id of the mime type
87 * @props: the properties to add to this capability
89 * Create a new capability with the given mime typeid and properties.
91 * Returns: a new capability
94 gst_caps_new_id (const gchar *name, const guint16 id, GstProps *props)
98 g_mutex_lock (_gst_caps_chunk_lock);
99 caps = g_mem_chunk_alloc (_gst_caps_chunk);
100 g_mutex_unlock (_gst_caps_chunk_lock);
102 caps->name = g_strdup (name);
104 caps->properties = props;
107 caps->lock = g_mutex_new ();
109 caps->fixed = props->fixed;
118 * @caps: the caps to destroy
120 * Frees the memory used by this caps structure and all
121 * the chained caps and properties.
124 gst_caps_destroy (GstCaps *caps)
131 GST_CAPS_LOCK (caps);
133 GST_CAPS_UNLOCK (caps);
135 g_mutex_free (caps->lock);
136 gst_props_unref (caps->properties);
138 g_mutex_lock (_gst_caps_chunk_lock);
139 g_mem_chunk_free (_gst_caps_chunk, caps);
140 g_mutex_unlock (_gst_caps_chunk_lock);
143 gst_caps_unref (next);
147 gst_caps_debug (GstCaps *caps)
149 GST_DEBUG_ENTER ("caps debug");
151 GST_DEBUG (GST_CAT_CAPS, "caps: %p %s %s\n", caps, caps->name, gst_caps_get_mime (caps));
153 if (caps->properties) {
154 gst_props_debug (caps->properties);
157 GST_DEBUG (GST_CAT_CAPS, "no properties\n");
162 GST_DEBUG_LEAVE ("caps debug");
167 * @caps: the caps to unref
169 * Decrease the refcount of this caps structure,
170 * destroying it when the refcount is 0
172 * Returns: caps or NULL if the refcount reached 0
175 gst_caps_unref (GstCaps *caps)
183 g_return_val_if_fail (caps->refcount > 0, NULL);
185 GST_CAPS_LOCK (caps);
187 zero = (caps->refcount == 0);
189 GST_CAPS_UNLOCK (caps);
192 *next = gst_caps_unref (*next);
195 gst_caps_destroy (caps);
203 * @caps: the caps to ref
205 * Increase the refcount of this caps structure
207 * Returns: the caps with the refcount incremented
210 gst_caps_ref (GstCaps *caps)
212 g_return_val_if_fail (caps != NULL, NULL);
214 GST_CAPS_LOCK (caps);
216 GST_CAPS_UNLOCK (caps);
223 * @caps: the caps to copy
225 * Copies the caps, not copying any chained caps.
227 * Returns: a copy of the GstCaps structure.
230 gst_caps_copy_1 (GstCaps *caps)
237 newcaps = gst_caps_new_id (
240 gst_props_copy (caps->properties));
247 * @caps: the caps to copy
251 * Returns: a copy of the GstCaps structure.
254 gst_caps_copy (GstCaps *caps)
256 GstCaps *new = NULL, *walk = NULL;
261 newcaps = gst_caps_copy_1 (caps);
264 new = walk = newcaps;
267 walk = walk->next = newcaps;
276 * gst_caps_copy_on_write:
277 * @caps: the caps to copy
279 * Copies the caps if the refcount is greater than 1
281 * Returns: a pointer to a GstCaps strcuture that can
282 * be safely written to
285 gst_caps_copy_on_write (GstCaps *caps)
290 g_return_val_if_fail (caps != NULL, NULL);
292 GST_CAPS_LOCK (caps);
293 needcopy = (caps->refcount > 1);
294 GST_CAPS_UNLOCK (caps);
297 new = gst_caps_copy (caps);
298 gst_caps_unref (caps);
306 * @caps: the caps to get the name from
308 * Get the name of a GstCaps structure.
310 * Returns: the name of the caps
313 gst_caps_get_name (GstCaps *caps)
315 g_return_val_if_fail (caps != NULL, NULL);
317 return (const gchar *)caps->name;
322 * @caps: the caps to set the name to
323 * @name: the name to set
325 * Set the name of a caps.
328 gst_caps_set_name (GstCaps *caps, const gchar *name)
330 g_return_if_fail (caps != NULL);
335 caps->name = g_strdup (name);
340 * @caps: the caps to get the mime type from
342 * Get the mime type of the caps as a string.
344 * Returns: the mime type of the caps
347 gst_caps_get_mime (GstCaps *caps)
351 g_return_val_if_fail (caps != NULL, NULL);
353 type = gst_type_find_by_id (caps->id);
358 return "unknown/unknown";
363 * @caps: the caps to set the mime type to
364 * @mime: the mime type to attach to the caps
366 * Set the mime type of the caps as a string.
369 gst_caps_set_mime (GstCaps *caps, const gchar *mime)
371 g_return_if_fail (caps != NULL);
372 g_return_if_fail (mime != NULL);
374 caps->id = get_type_for_mime (mime);
378 * gst_caps_get_type_id:
379 * @caps: the caps to get the type id from
381 * Get the type id of the caps.
383 * Returns: the type id of the caps
386 gst_caps_get_type_id (GstCaps *caps)
388 g_return_val_if_fail (caps != NULL, 0);
394 * gst_caps_set_type_id:
395 * @caps: the caps to set the type id to
396 * @type_id: the type id to set
398 * Set the type id of the caps.
401 gst_caps_set_type_id (GstCaps *caps, guint16 type_id)
403 g_return_if_fail (caps != NULL);
409 * gst_caps_set_props:
410 * @caps: the caps to attach the properties to
411 * @props: the properties to attach
413 * Set the properties to the given caps.
415 * Returns: the new caps structure
418 gst_caps_set_props (GstCaps *caps, GstProps *props)
420 g_return_val_if_fail (caps != NULL, caps);
421 g_return_val_if_fail (props != NULL, caps);
422 g_return_val_if_fail (caps->properties == NULL, caps);
424 caps->properties = props;
430 * gst_caps_get_props:
431 * @caps: the caps to get the properties from
433 * Get the properties of the given caps.
435 * Returns: the properties of the caps
438 gst_caps_get_props (GstCaps *caps)
440 g_return_val_if_fail (caps != NULL, NULL);
442 return caps->properties;
448 * @...: more capabilities
450 * chains the given capabilities
452 * Returns: the new capability
455 gst_caps_chain (GstCaps *caps, ...)
457 GstCaps *orig = caps;
460 va_start (var_args, caps);
465 toadd = va_arg (var_args, GstCaps*);
466 gst_caps_append (caps, toadd);
478 * @capstoadd: the capability to append
480 * Appends a capability to the existing capability.
482 * Returns: the new capability
485 gst_caps_append (GstCaps *caps, GstCaps *capstoadd)
487 GstCaps *orig = caps;
489 if (caps == NULL || caps == capstoadd)
495 caps->next = capstoadd;
503 * @capstoadd: a capabilty to prepend
505 * prepend the capability to the list of capabilities
507 * Returns: the new capability
510 gst_caps_prepend (GstCaps *caps, GstCaps *capstoadd)
512 GstCaps *orig = capstoadd;
514 if (capstoadd == NULL)
517 g_return_val_if_fail (caps != capstoadd, caps);
519 while (capstoadd->next) {
520 capstoadd = capstoadd->next;
522 capstoadd->next = caps;
528 * gst_caps_get_by_name:
530 * @name: the name of the capability to get
532 * Get the capability with the given name from this
533 * chain of capabilities.
535 * Returns: the first capability in the chain with the
539 gst_caps_get_by_name (GstCaps *caps, const gchar *name)
541 g_return_val_if_fail (caps != NULL, NULL);
542 g_return_val_if_fail (name != NULL, NULL);
545 if (!strcmp (caps->name, name))
554 gst_caps_check_compatibility_func (GstCaps *fromcaps, GstCaps *tocaps)
556 if (fromcaps->id != tocaps->id) {
557 GST_DEBUG (GST_CAT_CAPS,"mime types differ (%s to %s)\n",
558 gst_type_find_by_id (fromcaps->id)->mime,
559 gst_type_find_by_id (tocaps->id)->mime);
563 if (tocaps->properties) {
564 if (fromcaps->properties) {
565 return gst_props_check_compatibility (fromcaps->properties, tocaps->properties);
568 GST_DEBUG (GST_CAT_CAPS,"no source caps\n");
573 /* assume it accepts everything */
574 GST_DEBUG (GST_CAT_CAPS,"no caps\n");
580 * gst_caps_check_compatibility:
581 * @fromcaps: a capabilty
582 * @tocaps: a capabilty
584 * Checks whether two capabilities are compatible.
586 * Returns: TRUE if compatible, FALSE otherwise
589 gst_caps_check_compatibility (GstCaps *fromcaps, GstCaps *tocaps)
591 if (fromcaps == NULL) {
592 if (tocaps == NULL) {
593 GST_DEBUG (GST_CAT_CAPS,"no caps\n");
597 GST_DEBUG (GST_CAT_CAPS,"no source but destination caps\n");
602 if (tocaps == NULL) {
603 GST_DEBUG (GST_CAT_CAPS,"source caps and no destination caps\n");
609 GstCaps *destcaps = tocaps;
612 if (gst_caps_check_compatibility_func (fromcaps, destcaps))
615 destcaps = destcaps->next;
617 fromcaps = fromcaps->next;
623 gst_caps_intersect_func (GstCaps *caps1, GstCaps *caps2)
625 GstCaps *result = NULL;
628 if (caps1->id != caps2->id) {
629 GST_DEBUG (GST_CAT_CAPS,"mime types differ (%s to %s)\n",
630 gst_type_find_by_id (caps1->id)->mime,
631 gst_type_find_by_id (caps2->id)->mime);
635 if (caps1->properties == NULL) {
636 return gst_caps_ref (caps2);
638 if (caps2->properties == NULL) {
639 return gst_caps_ref (caps1);
642 props = gst_props_intersect (caps1->properties, caps2->properties);
644 result = gst_caps_new_id ("intersect", caps1->id, props);
651 * gst_caps_intersect:
652 * @caps1: a capabilty
653 * @caps2: a capabilty
655 * Make the intersection between two caps.
657 * Returns: The intersection of the two caps or NULL if the intersection
661 gst_caps_intersect (GstCaps *caps1, GstCaps *caps2)
663 GstCaps *result = NULL, *walk = NULL;
666 GST_DEBUG (GST_CAT_CAPS, "first caps is NULL, return other caps\n");
667 return gst_caps_copy (caps2);
670 GST_DEBUG (GST_CAT_CAPS, "second caps is NULL, return other caps\n");
671 return gst_caps_copy (caps1);
675 GstCaps *othercaps = caps2;
678 GstCaps *intersection;
680 intersection = gst_caps_intersect_func (caps1, othercaps);
684 walk = result = intersection;
687 walk = walk->next = intersection;
690 othercaps = othercaps->next;
699 gst_caps_normalize (GstCaps *caps)
701 GstCaps *result = NULL, *walk = caps;
709 proplist = gst_props_normalize (caps->properties);
710 if (proplist && g_list_next (proplist) == NULL) {
712 walk = result = caps;
714 walk = walk->next = caps;
720 GstProps *props = (GstProps *) proplist->data;
721 GstCaps *newcaps = gst_caps_new_id (caps->name, caps->id, props);
724 walk = result = newcaps;
726 walk = walk->next = newcaps;
728 proplist = g_list_next (proplist);
736 #ifndef GST_DISABLE_LOADSAVE_REGISTRY
738 * gst_caps_save_thyself:
739 * @caps: a capabilty to save
740 * @parent: the parent XML node pointer
742 * Save the capability into an XML representation.
744 * Returns: a new XML node pointer
747 gst_caps_save_thyself (GstCaps *caps, xmlNodePtr parent)
750 xmlNodePtr subsubtree;
753 subtree = xmlNewChild (parent, NULL, "capscomp", NULL);
755 xmlNewChild (subtree, NULL, "name", caps->name);
756 xmlNewChild (subtree, NULL, "type", gst_type_find_by_id (caps->id)->mime);
757 if (caps->properties) {
758 subsubtree = xmlNewChild (subtree, NULL, "properties", NULL);
760 gst_props_save_thyself (caps->properties, subsubtree);
770 * gst_caps_load_thyself:
771 * @parent: the parent XML node pointer
773 * Load a new caps from the XML representation.
775 * Returns: a new capability
778 gst_caps_load_thyself (xmlNodePtr parent)
780 GstCaps *result = NULL;
781 xmlNodePtr field = parent->xmlChildrenNode;
784 if (!strcmp (field->name, "capscomp")) {
785 xmlNodePtr subfield = field->xmlChildrenNode;
789 g_mutex_lock (_gst_caps_chunk_lock);
790 caps = g_mem_chunk_alloc0 (_gst_caps_chunk);
791 g_mutex_unlock (_gst_caps_chunk_lock);
794 caps->lock = g_mutex_new ();
799 if (!strcmp (subfield->name, "name")) {
800 caps->name = xmlNodeGetContent (subfield);
802 if (!strcmp (subfield->name, "type")) {
803 content = xmlNodeGetContent (subfield);
804 caps->id = get_type_for_mime (content);
807 else if (!strcmp (subfield->name, "properties")) {
808 caps->properties = gst_props_load_thyself (subfield);
811 subfield = subfield->next;
813 result = gst_caps_append (result, caps);
821 #endif /* GST_DISABLE_LOADSAVE_REGISTRY */