1 /*
2 * Copyright © 2007, 2008 Ryan Lortie
3 * Copyright © 2010 Codethink Limited
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the licence, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 * Boston, MA 02111-1307, USA.
19 *
20 * Author: Ryan Lortie <desrt@desrt.ca>
21 */
22
23 /* Prologue {{{1 */
24
25 #include "config.h"
26
27 #include <glib/gvariant-serialiser.h>
28 #include "gvariant-internal.h"
29 #include <glib/gvariant-core.h>
30 #include <glib/gtestutils.h>
31 #include <glib/gstrfuncs.h>
32 #include <glib/ghash.h>
33 #include <glib/gmem.h>
34
35 #include <string.h>
36
37
38 /**
39 * SECTION:gvariant
40 * @title: GVariant
41 * @short_description: strongly typed value datatype
42 * @see_also: GVariantType
43 *
44 * #GVariant is a variant datatype; it stores a value along with
45 * information about the type of that value. The range of possible
46 * values is determined by the type. The type system used by #GVariant
47 * is #GVariantType.
48 *
49 * #GVariant instances always have a type and a value (which are given
50 * at construction time). The type and value of a #GVariant instance
51 * can never change other than by the #GVariant itself being
52 * destroyed. A #GVariant can not contain a pointer.
53 *
54 * #GVariant is reference counted using g_variant_ref() and
55 * g_variant_unref(). #GVariant also has floating reference counts --
56 * see g_variant_ref_sink().
57 *
58 * #GVariant is completely threadsafe. A #GVariant instance can be
59 * concurrently accessed in any way from any number of threads without
60 * problems.
61 *
62 * #GVariant is heavily optimised for dealing with data in serialised
63 * form. It works particularly well with data located in memory-mapped
64 * files. It can perform nearly all deserialisation operations in a
65 * small constant time, usually touching only a single memory page.
66 * Serialised #GVariant data can also be sent over the network.
67 *
68 * #GVariant is largely compatible with D-Bus. Almost all types of
69 * #GVariant instances can be sent over D-Bus. See #GVariantType for
70 * exceptions.
71 *
72 * For convenience to C programmers, #GVariant features powerful
73 * varargs-based value construction and destruction. This feature is
74 * designed to be embedded in other libraries.
75 *
76 * There is a Python-inspired text language for describing #GVariant
77 * values. #GVariant includes a printer for this language and a parser
78 * with type inferencing.
79 *
80 * <refsect2>
81 * <title>Memory Use</title>
82 * <para>
83 * #GVariant tries to be quite efficient with respect to memory use.
84 * This section gives a rough idea of how much memory is used by the
85 * current implementation. The information here is subject to change
86 * in the future.
87 * </para>
88 * <para>
89 * The memory allocated by #GVariant can be grouped into 4 broad
90 * purposes: memory for serialised data, memory for the type
91 * information cache, buffer management memory and memory for the
92 * #GVariant structure itself.
93 * </para>
94 * <refsect3>
95 * <title>Serialised Data Memory</title>
96 * <para>
97 * This is the memory that is used for storing GVariant data in
98 * serialised form. This is what would be sent over the network or
99 * what would end up on disk.
100 * </para>
101 * <para>
102 * The amount of memory required to store a boolean is 1 byte. 16,
103 * 32 and 64 bit integers and double precision floating point numbers
104 * use their "natural" size. Strings (including object path and
105 * signature strings) are stored with a nul terminator, and as such
106 * use the length of the string plus 1 byte.
107 * </para>
108 * <para>
109 * Maybe types use no space at all to represent the null value and
110 * use the same amount of space (sometimes plus one byte) as the
111 * equivalent non-maybe-typed value to represent the non-null case.
112 * </para>
113 * <para>
114 * Arrays use the amount of space required to store each of their
115 * members, concatenated. Additionally, if the items stored in an
116 * array are not of a fixed-size (ie: strings, other arrays, etc)
117 * then an additional framing offset is stored for each item. The
118 * size of this offset is either 1, 2 or 4 bytes depending on the
119 * overall size of the container. Additionally, extra padding bytes
120 * are added as required for alignment of child values.
121 * </para>
122 * <para>
123 * Tuples (including dictionary entries) use the amount of space
124 * required to store each of their members, concatenated, plus one
125 * framing offset (as per arrays) for each non-fixed-sized item in
126 * the tuple, except for the last one. Additionally, extra padding
127 * bytes are added as required for alignment of child values.
128 * </para>
129 * <para>
130 * Variants use the same amount of space as the item inside of the
131 * variant, plus 1 byte, plus the length of the type string for the
132 * item inside the variant.
133 * </para>
134 * <para>
135 * As an example, consider a dictionary mapping strings to variants.
136 * In the case that the dictionary is empty, 0 bytes are required for
137 * the serialisation.
138 * </para>
139 * <para>
140 * If we add an item "width" that maps to the int32 value of 500 then
141 * we will use 4 byte to store the int32 (so 6 for the variant
142 * containing it) and 6 bytes for the string. The variant must be
143 * aligned to 8 after the 6 bytes of the string, so that's 2 extra
144 * bytes. 6 (string) + 2 (padding) + 6 (variant) is 14 bytes used
145 * for the dictionary entry. An additional 1 byte is added to the
146 * array as a framing offset making a total of 15 bytes.
147 * </para>
148 * <para>
149 * If we add another entry, "title" that maps to a nullable string
150 * that happens to have a value of null, then we use 0 bytes for the
151 * null value (and 3 bytes for the variant to contain it along with
152 * its type string) plus 6 bytes for the string. Again, we need 2
153 * padding bytes. That makes a total of 6 + 2 + 3 = 11 bytes.
154 * </para>
155 * <para>
156 * We now require extra padding between the two items in the array.
157 * After the 14 bytes of the first item, that's 2 bytes required. We
158 * now require 2 framing offsets for an extra two bytes. 14 + 2 + 11
159 * + 2 = 29 bytes to encode the entire two-item dictionary.
160 * </para>
161 * </refsect3>
162 * <refsect3>
163 * <title>Type Information Cache</title>
164 * <para>
165 * For each GVariant type that currently exists in the program a type
166 * information structure is kept in the type information cache. The
167 * type information structure is required for rapid deserialisation.
168 * </para>
169 * <para>
170 * Continuing with the above example, if a #GVariant exists with the
171 * type "a{sv}" then a type information struct will exist for
172 * "a{sv}", "{sv}", "s", and "v". Multiple uses of the same type
173 * will share the same type information. Additionally, all
174 * single-digit types are stored in read-only static memory and do
175 * not contribute to the writable memory footprint of a program using
176 * #GVariant.
177 * </para>
178 * <para>
179 * Aside from the type information structures stored in read-only
180 * memory, there are two forms of type information. One is used for
181 * container types where there is a single element type: arrays and
182 * maybe types. The other is used for container types where there
183 * are multiple element types: tuples and dictionary entries.
184 * </para>
185 * <para>
186 * Array type info structures are 6 * sizeof (void *), plus the
187 * memory required to store the type string itself. This means that
188 * on 32bit systems, the cache entry for "a{sv}" would require 30
189 * bytes of memory (plus malloc overhead).
190 * </para>
191 * <para>
192 * Tuple type info structures are 6 * sizeof (void *), plus 4 *
193 * sizeof (void *) for each item in the tuple, plus the memory
194 * required to store the type string itself. A 2-item tuple, for
195 * example, would have a type information structure that consumed
196 * writable memory in the size of 14 * sizeof (void *) (plus type
197 * string) This means that on 32bit systems, the cache entry for
198 * "{sv}" would require 61 bytes of memory (plus malloc overhead).
199 * </para>
200 * <para>
201 * This means that in total, for our "a{sv}" example, 91 bytes of
202 * type information would be allocated.
203 * </para>
204 * <para>
205 * The type information cache, additionally, uses a #GHashTable to
206 * store and lookup the cached items and stores a pointer to this
207 * hash table in static storage. The hash table is freed when there
208 * are zero items in the type cache.
209 * </para>
210 * <para>
211 * Although these sizes may seem large it is important to remember
212 * that a program will probably only have a very small number of
213 * different types of values in it and that only one type information
214 * structure is required for many different values of the same type.
215 * </para>
216 * </refsect3>
217 * <refsect3>
218 * <title>Buffer Management Memory</title>
219 * <para>
220 * #GVariant uses an internal buffer management structure to deal
221 * with the various different possible sources of serialised data
222 * that it uses. The buffer is responsible for ensuring that the
223 * correct call is made when the data is no longer in use by
224 * #GVariant. This may involve a g_free() or a g_slice_free() or
225 * even g_mapped_file_unref().
226 * </para>
227 * <para>
228 * One buffer management structure is used for each chunk of
229 * serialised data. The size of the buffer management structure is 4
230 * * (void *). On 32bit systems, that's 16 bytes.
231 * </para>
232 * </refsect3>
233 * <refsect3>
234 * <title>GVariant structure</title>
235 * <para>
236 * The size of a #GVariant structure is 6 * (void *). On 32 bit
237 * systems, that's 24 bytes.
238 * </para>
239 * <para>
240 * #GVariant structures only exist if they are explicitly created
241 * with API calls. For example, if a #GVariant is constructed out of
242 * serialised data for the example given above (with the dictionary)
243 * then although there are 9 individual values that comprise the
244 * entire dictionary (two keys, two values, two variants containing
245 * the values, two dictionary entries, plus the dictionary itself),
246 * only 1 #GVariant instance exists -- the one refering to the
247 * dictionary.
248 * </para>
249 * <para>
250 * If calls are made to start accessing the other values then
251 * #GVariant instances will exist for those values only for as long
252 * as they are in use (ie: until you call g_variant_unref()). The
253 * type information is shared. The serialised data and the buffer
254 * management structure for that serialised data is shared by the
255 * child.
256 * </para>
257 * </refsect3>
258 * <refsect3>
259 * <title>Summary</title>
260 * <para>
261 * To put the entire example together, for our dictionary mapping
262 * strings to variants (with two entries, as given above), we are
263 * using 91 bytes of memory for type information, 29 byes of memory
264 * for the serialised data, 16 bytes for buffer management and 24
265 * bytes for the #GVariant instance, or a total of 160 bytes, plus
266 * malloc overhead. If we were to use g_variant_get_child_value() to
267 * access the two dictionary entries, we would use an additional 48
268 * bytes. If we were to have other dictionaries of the same type, we
269 * would use more memory for the serialised data and buffer
270 * management for those dictionaries, but the type information would
271 * be shared.
272 * </para>
273 * </refsect3>
274 * </refsect2>
275 */
276
277 /* definition of GVariant structure is in gvariant-core.c */
278
279 /* this is a g_return_val_if_fail() for making
280 * sure a (GVariant *) has the required type.
281 */
282 #define TYPE_CHECK(value, TYPE, val) \
283 if G_UNLIKELY (!g_variant_is_of_type (value, TYPE)) { \
284 g_return_if_fail_warning (G_LOG_DOMAIN, G_STRFUNC, \
285 "g_variant_is_of_type (" #value \
286 ", " #TYPE ")"); \
287 return val; \
288 }
289
290 /* Numeric Type Constructor/Getters {{{1 */
291 /* < private >
292 * g_variant_new_from_trusted:
293 * @type: the #GVariantType
294 * @data: the data to use
295 * @size: the size of @data
296 * @returns: a new floating #GVariant
297 *
298 * Constructs a new trusted #GVariant instance from the provided data.
299 * This is used to implement g_variant_new_* for all the basic types.
300 */
301 static GVariant *
302 g_variant_new_from_trusted (const GVariantType *type,
303 gconstpointer data,
304 gsize size)
305 {
306 GVariant *value;
307 GBuffer *buffer;
308
309 buffer = g_buffer_new_from_data (data, size);
310 value = g_variant_new_from_buffer (type, buffer, TRUE);
311 g_buffer_unref (buffer);
312
313 return value;
314 }
315
316 /**
317 * g_variant_new_boolean:
318 * @value: a #gboolean value
319 * @returns: (transfer none): a floating reference to a new boolean #GVariant instance
320 *
321 * Creates a new boolean #GVariant instance -- either %TRUE or %FALSE.
322 *
323 * Since: 2.24
324 **/
325 GVariant *
326 g_variant_new_boolean (gboolean value)
327 {
328 guchar v = value;
329
330 return g_variant_new_from_trusted (G_VARIANT_TYPE_BOOLEAN, &v, 1);
331 }
332
333 /**
334 * g_variant_get_boolean:
335 * @value: a boolean #GVariant instance
336 * @returns: %TRUE or %FALSE
337 *
338 * Returns the boolean value of @value.
339 *
340 * It is an error to call this function with a @value of any type
341 * other than %G_VARIANT_TYPE_BOOLEAN.
342 *
343 * Since: 2.24
344 **/
345 gboolean
346 g_variant_get_boolean (GVariant *value)
347 {
348 const guchar *data;
349
350 TYPE_CHECK (value, G_VARIANT_TYPE_BOOLEAN, FALSE);
351
352 data = g_variant_get_data (value);
353
354 return data != NULL ? *data != 0 : FALSE;
355 }
356
357 /* the constructors and accessors for byte, int{16,32,64}, handles and
358 * doubles all look pretty much exactly the same, so we reduce
359 * copy/pasting here.
360 */
361 #define NUMERIC_TYPE(TYPE, type, ctype) \
362 GVariant *g_variant_new_##type (ctype value) { \
363 return g_variant_new_from_trusted (G_VARIANT_TYPE_##TYPE, \
364 &value, sizeof value); \
365 } \
366 ctype g_variant_get_##type (GVariant *value) { \
367 const ctype *data; \
368 TYPE_CHECK (value, G_VARIANT_TYPE_ ## TYPE, 0); \
369 data = g_variant_get_data (value); \
370 return data != NULL ? *data : 0; \
371 }
372
373
374 /**
375 * g_variant_new_byte:
376 * @value: a #guint8 value
377 * @returns: (transfer none): a floating reference to a new byte #GVariant instance
378 *
379 * Creates a new byte #GVariant instance.
380 *
381 * Since: 2.24
382 **/
383 /**
384 * g_variant_get_byte:
385 * @value: a byte #GVariant instance
386 * @returns: a #guchar
387 *
388 * Returns the byte value of @value.
389 *
390 * It is an error to call this function with a @value of any type
391 * other than %G_VARIANT_TYPE_BYTE.
392 *
393 * Since: 2.24
394 **/
395 NUMERIC_TYPE (BYTE, byte, guchar)
396
397 /**
398 * g_variant_new_int16:
399 * @value: a #gint16 value
400 * @returns: (transfer none): a floating reference to a new int16 #GVariant instance
401 *
402 * Creates a new int16 #GVariant instance.
403 *
404 * Since: 2.24
405 **/
406 /**
407 * g_variant_get_int16:
408 * @value: a int16 #GVariant instance
409 * @returns: a #gint16
410 *
411 * Returns the 16-bit signed integer value of @value.
412 *
413 * It is an error to call this function with a @value of any type
414 * other than %G_VARIANT_TYPE_INT16.
415 *
416 * Since: 2.24
417 **/
418 NUMERIC_TYPE (INT16, int16, gint16)
419
420 /**
421 * g_variant_new_uint16:
422 * @value: a #guint16 value
423 * @returns: (transfer none): a floating reference to a new uint16 #GVariant instance
424 *
425 * Creates a new uint16 #GVariant instance.
426 *
427 * Since: 2.24
428 **/
429 /**
430 * g_variant_get_uint16:
431 * @value: a uint16 #GVariant instance
432 * @returns: a #guint16
433 *
434 * Returns the 16-bit unsigned integer value of @value.
435 *
436 * It is an error to call this function with a @value of any type
437 * other than %G_VARIANT_TYPE_UINT16.
438 *
439 * Since: 2.24
440 **/
441 NUMERIC_TYPE (UINT16, uint16, guint16)
442
443 /**
444 * g_variant_new_int32:
445 * @value: a #gint32 value
446 * @returns: (transfer none): a floating reference to a new int32 #GVariant instance
447 *
448 * Creates a new int32 #GVariant instance.
449 *
450 * Since: 2.24
451 **/
452 /**
453 * g_variant_get_int32:
454 * @value: a int32 #GVariant instance
455 * @returns: a #gint32
456 *
457 * Returns the 32-bit signed integer value of @value.
458 *
459 * It is an error to call this function with a @value of any type
460 * other than %G_VARIANT_TYPE_INT32.
461 *
462 * Since: 2.24
463 **/
464 NUMERIC_TYPE (INT32, int32, gint32)
465
466 /**
467 * g_variant_new_uint32:
468 * @value: a #guint32 value
469 * @returns: (transfer none): a floating reference to a new uint32 #GVariant instance
470 *
471 * Creates a new uint32 #GVariant instance.
472 *
473 * Since: 2.24
474 **/
475 /**
476 * g_variant_get_uint32:
477 * @value: a uint32 #GVariant instance
478 * @returns: a #guint32
479 *
480 * Returns the 32-bit unsigned integer value of @value.
481 *
482 * It is an error to call this function with a @value of any type
483 * other than %G_VARIANT_TYPE_UINT32.
484 *
485 * Since: 2.24
486 **/
487 NUMERIC_TYPE (UINT32, uint32, guint32)
488
489 /**
490 * g_variant_new_int64:
491 * @value: a #gint64 value
492 * @returns: (transfer none): a floating reference to a new int64 #GVariant instance
493 *
494 * Creates a new int64 #GVariant instance.
495 *
496 * Since: 2.24
497 **/
498 /**
499 * g_variant_get_int64:
500 * @value: a int64 #GVariant instance
501 * @returns: a #gint64
502 *
503 * Returns the 64-bit signed integer value of @value.
504 *
505 * It is an error to call this function with a @value of any type
506 * other than %G_VARIANT_TYPE_INT64.
507 *
508 * Since: 2.24
509 **/
510 NUMERIC_TYPE (INT64, int64, gint64)
511
512 /**
513 * g_variant_new_uint64:
514 * @value: a #guint64 value
515 * @returns: (transfer none): a floating reference to a new uint64 #GVariant instance
516 *
517 * Creates a new uint64 #GVariant instance.
518 *
519 * Since: 2.24
520 **/
521 /**
522 * g_variant_get_uint64:
523 * @value: a uint64 #GVariant instance
524 * @returns: a #guint64
525 *
526 * Returns the 64-bit unsigned integer value of @value.
527 *
528 * It is an error to call this function with a @value of any type
529 * other than %G_VARIANT_TYPE_UINT64.
530 *
531 * Since: 2.24
532 **/
533 NUMERIC_TYPE (UINT64, uint64, guint64)
534
535 /**
536 * g_variant_new_handle:
537 * @value: a #gint32 value
538 * @returns: (transfer none): a floating reference to a new handle #GVariant instance
539 *
540 * Creates a new handle #GVariant instance.
541 *
542 * By convention, handles are indexes into an array of file descriptors
543 * that are sent alongside a D-Bus message. If you're not interacting
544 * with D-Bus, you probably don't need them.
545 *
546 * Since: 2.24
547 **/
548 /**
549 * g_variant_get_handle:
550 * @value: a handle #GVariant instance
551 * @returns: a #gint32
552 *
553 * Returns the 32-bit signed integer value of @value.
554 *
555 * It is an error to call this function with a @value of any type other
556 * than %G_VARIANT_TYPE_HANDLE.
557 *
558 * By convention, handles are indexes into an array of file descriptors
559 * that are sent alongside a D-Bus message. If you're not interacting
560 * with D-Bus, you probably don't need them.
561 *
562 * Since: 2.24
563 **/
564 NUMERIC_TYPE (HANDLE, handle, gint32)
565
566 /**
567 * g_variant_new_double:
568 * @value: a #gdouble floating point value
569 * @returns: (transfer none): a floating reference to a new double #GVariant instance
570 *
571 * Creates a new double #GVariant instance.
572 *
573 * Since: 2.24
574 **/
575 /**
576 * g_variant_get_double:
577 * @value: a double #GVariant instance
578 * @returns: a #gdouble
579 *
580 * Returns the double precision floating point value of @value.
581 *
582 * It is an error to call this function with a @value of any type
583 * other than %G_VARIANT_TYPE_DOUBLE.
584 *
585 * Since: 2.24
586 **/
587 NUMERIC_TYPE (DOUBLE, double, gdouble)
588
589 /* Container type Constructor / Deconstructors {{{1 */
590 /**
591 * g_variant_new_maybe:
592 * @child_type: (allow-none): the #GVariantType of the child, or %NULL
593 * @child: (allow-none): the child value, or %NULL
594 * @returns: (transfer none): a floating reference to a new #GVariant maybe instance
595 *
596 * Depending on if @child is %NULL, either wraps @child inside of a
597 * maybe container or creates a Nothing instance for the given @type.
598 *
599 * At least one of @child_type and @child must be non-%NULL.
600 * If @child_type is non-%NULL then it must be a definite type.
601 * If they are both non-%NULL then @child_type must be the type
602 * of @child.
603 *
604 * If @child is a floating reference (see g_variant_ref_sink()), the new
605 * instance takes ownership of @child.
606 *
607 * Since: 2.24
608 **/
609 GVariant *
610 g_variant_new_maybe (const GVariantType *child_type,
611 GVariant *child)
612 {
613 GVariantType *maybe_type;
614 GVariant *value;
615
616 g_return_val_if_fail (child_type == NULL || g_variant_type_is_definite
617 (child_type), 0);
618 g_return_val_if_fail (child_type != NULL || child != NULL, NULL);
619 g_return_val_if_fail (child_type == NULL || child == NULL ||
620 g_variant_is_of_type (child, child_type),
621 NULL);
622
623 if (child_type == NULL)
624 child_type = g_variant_get_type (child);
625
626 maybe_type = g_variant_type_new_maybe (child_type);
627
628 if (child != NULL)
629 {
630 GVariant **children;
631 gboolean trusted;
632
633 children = g_new (GVariant *, 1);
634 children[0] = g_variant_ref_sink (child);
635 trusted = g_variant_is_trusted (children[0]);
636
637 value = g_variant_new_from_children (maybe_type, children, 1, trusted);
638 }
639 else
640 value = g_variant_new_from_children (maybe_type, NULL, 0, TRUE);
641
642 g_variant_type_free (maybe_type);
643
644 return value;
645 }
646
647 /**
648 * g_variant_get_maybe:
649 * @value: a maybe-typed value
650 * @returns: (allow-none) (transfer full): the contents of @value, or %NULL
651 *
652 * Given a maybe-typed #GVariant instance, extract its value. If the
653 * value is Nothing, then this function returns %NULL.
654 *
655 * Since: 2.24
656 **/
657 GVariant *
658 g_variant_get_maybe (GVariant *value)
659 {
660 TYPE_CHECK (value, G_VARIANT_TYPE_MAYBE, NULL);
661
662 if (g_variant_n_children (value))
663 return g_variant_get_child_value (value, 0);
664
665 return NULL;
666 }
667
668 /**
669 * g_variant_new_variant:
670 * @value: a #GVariant instance
671 * @returns: (transfer none): a floating reference to a new variant #GVariant instance
672 *
673 * Boxes @value. The result is a #GVariant instance representing a
674 * variant containing the original value.
675 *
676 * If @child is a floating reference (see g_variant_ref_sink()), the new
677 * instance takes ownership of @child.
678 *
679 * Since: 2.24
680 **/
681 GVariant *
682 g_variant_new_variant (GVariant *value)
683 {
684 g_return_val_if_fail (value != NULL, NULL);
685
686 g_variant_ref_sink (value);
687
688 return g_variant_new_from_children (G_VARIANT_TYPE_VARIANT,
689 g_memdup (&value, sizeof value),
690 1, g_variant_is_trusted (value));
691 }
692
693 /**
694 * g_variant_get_variant:
695 * @value: a variant #GVariant instance
696 * @returns: (transfer full): the item contained in the variant
697 *
698 * Unboxes @value. The result is the #GVariant instance that was
699 * contained in @value.
700 *
701 * Since: 2.24
702 **/
703 GVariant *
704 g_variant_get_variant (GVariant *value)
705 {
706 TYPE_CHECK (value, G_VARIANT_TYPE_VARIANT, NULL);
707
708 return g_variant_get_child_value (value, 0);
709 }
710
711 /**
712 * g_variant_new_array:
713 * @child_type: (allow-none): the element type of the new array
714 * @children: (allow-none) (array length=n_children): an array of
715 * #GVariant pointers, the children
716 * @n_children: the length of @children
717 * @returns: (transfer none): a floating reference to a new #GVariant array
718 *
719 * Creates a new #GVariant array from @children.
720 *
721 * @child_type must be non-%NULL if @n_children is zero. Otherwise, the
722 * child type is determined by inspecting the first element of the
723 * @children array. If @child_type is non-%NULL then it must be a
724 * definite type.
725 *
726 * The items of the array are taken from the @children array. No entry
727 * in the @children array may be %NULL.
728 *
729 * All items in the array must have the same type, which must be the
730 * same as @child_type, if given.
731 *
732 * If the @children are floating references (see g_variant_ref_sink()), the
733 * new instance takes ownership of them as if via g_variant_ref_sink().
734 *
735 * Since: 2.24
736 **/
737 GVariant *
738 g_variant_new_array (const GVariantType *child_type,
739 GVariant * const *children,
740 gsize n_children)
741 {
742 GVariantType *array_type;
743 GVariant **my_children;
744 gboolean trusted;
745 GVariant *value;
746 gsize i;
747
748 g_return_val_if_fail (n_children > 0 || child_type != NULL, NULL);
749 g_return_val_if_fail (n_children == 0 || children != NULL, NULL);
750 g_return_val_if_fail (child_type == NULL ||
751 g_variant_type_is_definite (child_type), NULL);
752
753 my_children = g_new (GVariant *, n_children);
754 trusted = TRUE;
755
756 if (child_type == NULL)
757 child_type = g_variant_get_type (children[0]);
758 array_type = g_variant_type_new_array (child_type);
759
760 for (i = 0; i < n_children; i++)
761 {
762 TYPE_CHECK (children[i], child_type, NULL);
763 my_children[i] = g_variant_ref_sink (children[i]);
764 trusted &= g_variant_is_trusted (children[i]);
765 }
766
767 value = g_variant_new_from_children (array_type, my_children,
768 n_children, trusted);
769 g_variant_type_free (array_type);
770
771 return value;
772 }
773
774 /*< private >
775 * g_variant_make_tuple_type:
776 * @children: (array length=n_children): an array of GVariant *
777 * @n_children: the length of @children
778 *
779 * Return the type of a tuple containing @children as its items.
780 **/
781 static GVariantType *
782 g_variant_make_tuple_type (GVariant * const *children,
783 gsize n_children)
784 {
785 const GVariantType **types;
786 GVariantType *type;
787 gsize i;
788
789 types = g_new (const GVariantType *, n_children);
790
791 for (i = 0; i < n_children; i++)
792 types[i] = g_variant_get_type (children[i]);
793
794 type = g_variant_type_new_tuple (types, n_children);
795 g_free (types);
796
797 return type;
798 }
799
800 /**
801 * g_variant_new_tuple:
802 * @children: (array length=n_children): the items to make the tuple out of
803 * @n_children: the length of @children
804 * @returns: (transfer none): a floating reference to a new #GVariant tuple
805 *
806 * Creates a new tuple #GVariant out of the items in @children. The
807 * type is determined from the types of @children. No entry in the
808 * @children array may be %NULL.
809 *
810 * If @n_children is 0 then the unit tuple is constructed.
811 *
812 * If the @children are floating references (see g_variant_ref_sink()), the
813 * new instance takes ownership of them as if via g_variant_ref_sink().
814 *
815 * Since: 2.24
816 **/
817 GVariant *
818 g_variant_new_tuple (GVariant * const *children,
819 gsize n_children)
820 {
821 GVariantType *tuple_type;
822 GVariant **my_children;
823 gboolean trusted;
824 GVariant *value;
825 gsize i;
826
827 g_return_val_if_fail (n_children == 0 || children != NULL, NULL);
828
829 my_children = g_new (GVariant *, n_children);
830 trusted = TRUE;
831
832 for (i = 0; i < n_children; i++)
833 {
834 my_children[i] = g_variant_ref_sink (children[i]);
835 trusted &= g_variant_is_trusted (children[i]);
836 }
837
838 tuple_type = g_variant_make_tuple_type (children, n_children);
839 value = g_variant_new_from_children (tuple_type, my_children,
840 n_children, trusted);
841 g_variant_type_free (tuple_type);
842
843 return value;
844 }
845
846 /*< private >
847 * g_variant_make_dict_entry_type:
848 * @key: a #GVariant, the key
849 * @val: a #GVariant, the value
850 *
851 * Return the type of a dictionary entry containing @key and @val as its
852 * children.
853 **/
854 static GVariantType *
855 g_variant_make_dict_entry_type (GVariant *key,
856 GVariant *val)
857 {
858 return g_variant_type_new_dict_entry (g_variant_get_type (key),
859 g_variant_get_type (val));
860 }
861
862 /**
863 * g_variant_new_dict_entry: (constructor)
864 * @key: a basic #GVariant, the key
865 * @value: a #GVariant, the value
866 * @returns: (transfer none): a floating reference to a new dictionary entry #GVariant
867 *
868 * Creates a new dictionary entry #GVariant. @key and @value must be
869 * non-%NULL. @key must be a value of a basic type (ie: not a container).
870 *
871 * If the @key or @value are floating references (see g_variant_ref_sink()),
872 * the new instance takes ownership of them as if via g_variant_ref_sink().
873 *
874 * Since: 2.24
875 **/
876 GVariant *
877 g_variant_new_dict_entry (GVariant *key,
878 GVariant *value)
879 {
880 GVariantType *dict_type;
881 GVariant **children;
882 gboolean trusted;
883
884 g_return_val_if_fail (key != NULL && value != NULL, NULL);
885 g_return_val_if_fail (!g_variant_is_container (key), NULL);
886
887 children = g_new (GVariant *, 2);
888 children[0] = g_variant_ref_sink (key);
889 children[1] = g_variant_ref_sink (value);
890 trusted = g_variant_is_trusted (key) && g_variant_is_trusted (value);
891
892 dict_type = g_variant_make_dict_entry_type (key, value);
893 value = g_variant_new_from_children (dict_type, children, 2, trusted);
894 g_variant_type_free (dict_type);
895
896 return value;
897 }
898
899 /**
900 * g_variant_lookup: (skip)
901 * @dictionary: a dictionary #GVariant
902 * @key: the key to lookup in the dictionary
903 * @format_string: a GVariant format string
904 * @...: the arguments to unpack the value into
905 *
906 * Looks up a value in a dictionary #GVariant.
907 *
908 * This function is a wrapper around g_variant_lookup_value() and
909 * g_variant_get(). In the case that %NULL would have been returned,
910 * this function returns %FALSE. Otherwise, it unpacks the returned
911 * value and returns %TRUE.
912 *
913 * See g_variant_get() for information about @format_string.
914 *
915 * Returns: %TRUE if a value was unpacked
916 *
917 * Since: 2.28
918 */
919 gboolean
920 g_variant_lookup (GVariant *dictionary,
921 const gchar *key,
922 const gchar *format_string,
923 ...)
924 {
925 GVariantType *type;
926 GVariant *value;
927
928 /* flatten */
929 g_variant_get_data (dictionary);
930
931 type = g_variant_format_string_scan_type (format_string, NULL, NULL);
932 value = g_variant_lookup_value (dictionary, key, type);
933 g_variant_type_free (type);
934
935 if (value)
936 {
937 va_list ap;
938
939 va_start (ap, format_string);
940 g_variant_get_va (value, format_string, NULL, &ap);
941 g_variant_unref (value);
942 va_end (ap);
943
944 return TRUE;
945 }
946
947 else
948 return FALSE;
949 }
950
951 /**
952 * g_variant_lookup_value:
953 * @dictionary: a dictionary #GVariant
954 * @key: the key to lookup in the dictionary
955 * @expected_type: (allow-none): a #GVariantType, or %NULL
956 *
957 * Looks up a value in a dictionary #GVariant.
958 *
959 * This function works with dictionaries of the type
960 * <literal>a{s*}</literal> (and equally well with type
961 * <literal>a{o*}</literal>, but we only further discuss the string case
962 * for sake of clarity).
963 *
964 * In the event that @dictionary has the type <literal>a{sv}</literal>,
965 * the @expected_type string specifies what type of value is expected to
966 * be inside of the variant. If the value inside the variant has a
967 * different type then %NULL is returned. In the event that @dictionary
968 * has a value type other than <literal>v</literal> then @expected_type
969 * must directly match the key type and it is used to unpack the value
970 * directly or an error occurs.
971 *
972 * In either case, if @key is not found in @dictionary, %NULL is
973 * returned.
974 *
975 * If the key is found and the value has the correct type, it is
976 * returned. If @expected_type was specified then any non-%NULL return
977 * value will have this type.
978 *
979 * Returns: (transfer full): the value of the dictionary key, or %NULL
980 *
981 * Since: 2.28
982 */
983 GVariant *
984 g_variant_lookup_value (GVariant *dictionary,
985 const gchar *key,
986 const GVariantType *expected_type)
987 {
988 GVariantIter iter;
989 GVariant *entry;
990 GVariant *value;
991
992 g_return_val_if_fail (g_variant_is_of_type (dictionary,
993 G_VARIANT_TYPE ("a{s*}")) ||
994 g_variant_is_of_type (dictionary,
995 G_VARIANT_TYPE ("a{o*}")),
996 NULL);
997
998 g_variant_iter_init (&iter, dictionary);
999
1000 while ((entry = g_variant_iter_next_value (&iter)))
1001 {
1002 GVariant *entry_key;
1003 gboolean matches;
1004
1005 entry_key = g_variant_get_child_value (entry, 0);
1006 matches = strcmp (g_variant_get_string (entry_key, NULL), key) == 0;
1007 g_variant_unref (entry_key);
1008
1009 if (matches)
1010 break;
1011
1012 g_variant_unref (entry);
1013 }
1014
1015 if (entry == NULL)
1016 return NULL;
1017
1018 value = g_variant_get_child_value (entry, 1);
1019 g_variant_unref (entry);
1020
1021 if (g_variant_is_of_type (value, G_VARIANT_TYPE_VARIANT))
1022 {
1023 GVariant *tmp;
1024
1025 tmp = g_variant_get_variant (value);
1026 g_variant_unref (value);
1027
1028 if (expected_type && !g_variant_is_of_type (tmp, expected_type))
1029 {
1030 g_variant_unref (tmp);
1031 tmp = NULL;
1032 }
1033
1034 value = tmp;
1035 }
1036
1037 g_return_val_if_fail (expected_type == NULL || value == NULL ||
1038 g_variant_is_of_type (value, expected_type), NULL);
1039
1040 return value;
1041 }
1042
1043 /**
1044 * g_variant_get_fixed_array:
1045 * @value: a #GVariant array with fixed-sized elements
1046 * @n_elements: (out): a pointer to the location to store the number of items
1047 * @element_size: the size of each element
1048 * @returns: (array length=n_elements): a pointer to the fixed array
1049 *
1050 * Provides access to the serialised data for an array of fixed-sized
1051 * items.
1052 *
1053 * @value must be an array with fixed-sized elements. Numeric types are
1054 * fixed-size as are tuples containing only other fixed-sized types.
1055 *
1056 * @element_size must be the size of a single element in the array. For
1057 * example, if calling this function for an array of 32 bit integers,
1058 * you might say <code>sizeof (gint32)</code>. This value isn't used
1059 * except for the purpose of a double-check that the form of the
1060 * seralised data matches the caller's expectation.
1061 *
1062 * @n_elements, which must be non-%NULL is set equal to the number of
1063 * items in the array.
1064 *
1065 * Since: 2.24
1066 **/
1067 gconstpointer
1068 g_variant_get_fixed_array (GVariant *value,
1069 gsize *n_elements,
1070 gsize element_size)
1071 {
1072 GVariantTypeInfo *array_info;
1073 gsize array_element_size;
1074 gconstpointer data;
1075 gsize size;
1076
1077 TYPE_CHECK (value, G_VARIANT_TYPE_ARRAY, NULL);
1078
1079 g_return_val_if_fail (n_elements != NULL, NULL);
1080 g_return_val_if_fail (element_size > 0, NULL);
1081
1082 array_info = g_variant_get_type_info (value);
1083 g_variant_type_info_query_element (array_info, NULL, &array_element_size);
1084
1085 g_return_val_if_fail (array_element_size, NULL);
1086
1087 if G_UNLIKELY (array_element_size != element_size)
1088 {
1089 if (array_element_size)
1090 g_critical ("g_variant_get_fixed_array: assertion "
1091 "`g_variant_array_has_fixed_size (value, element_size)' "
1092 "failed: array size %"G_GSIZE_FORMAT" does not match "
1093 "given element_size %"G_GSIZE_FORMAT".",
1094 array_element_size, element_size);
1095 else
1096 g_critical ("g_variant_get_fixed_array: assertion "
1097 "`g_variant_array_has_fixed_size (value, element_size)' "
1098 "failed: array does not have fixed size.");
1099 }
1100
1101 data = g_variant_get_data (value);
1102 size = g_variant_get_size (value);
1103
1104 if (size % element_size)
1105 *n_elements = 0;
1106 else
1107 *n_elements = size / element_size;
1108
1109 if (*n_elements)
1110 return data;
1111
1112 return NULL;
1113 }
1114
1115 /* String type constructor/getters/validation {{{1 */
1116 /**
1117 * g_variant_new_string:
1118 * @string: a normal utf8 nul-terminated string
1119 * @returns: (transfer none): a floating reference to a new string #GVariant instance
1120 *
1121 * Creates a string #GVariant with the contents of @string.
1122 *
1123 * @string must be valid utf8.
1124 *
1125 * Since: 2.24
1126 **/
1127 GVariant *
1128 g_variant_new_string (const gchar *string)
1129 {
1130 g_return_val_if_fail (string != NULL, NULL);
1131 g_return_val_if_fail (g_utf8_validate (string, -1, NULL), NULL);
1132
1133 return g_variant_new_from_trusted (G_VARIANT_TYPE_STRING,
1134 string, strlen (string) + 1);
1135 }
1136
1137 /**
1138 * g_variant_new_object_path:
1139 * @object_path: a normal C nul-terminated string
1140 * @returns: (transfer none): a floating reference to a new object path #GVariant instance
1141 *
1142 * Creates a D-Bus object path #GVariant with the contents of @string.
1143 * @string must be a valid D-Bus object path. Use
1144 * g_variant_is_object_path() if you're not sure.
1145 *
1146 * Since: 2.24
1147 **/
1148 GVariant *
1149 g_variant_new_object_path (const gchar *object_path)
1150 {
1151 g_return_val_if_fail (g_variant_is_object_path (object_path), NULL);
1152
1153 return g_variant_new_from_trusted (G_VARIANT_TYPE_OBJECT_PATH,
1154 object_path, strlen (object_path) + 1);
1155 }
1156
1157 /**
1158 * g_variant_is_object_path:
1159 * @string: a normal C nul-terminated string
1160 * @returns: %TRUE if @string is a D-Bus object path
1161 *
1162 * Determines if a given string is a valid D-Bus object path. You
1163 * should ensure that a string is a valid D-Bus object path before
1164 * passing it to g_variant_new_object_path().
1165 *
1166 * A valid object path starts with '/' followed by zero or more
1167 * sequences of characters separated by '/' characters. Each sequence
1168 * must contain only the characters "[A-Z][a-z][0-9]_". No sequence
1169 * (including the one following the final '/' character) may be empty.
1170 *
1171 * Since: 2.24
1172 **/
1173 gboolean
1174 g_variant_is_object_path (const gchar *string)
1175 {
1176 g_return_val_if_fail (string != NULL, FALSE);
1177
1178 return g_variant_serialiser_is_object_path (string, strlen (string) + 1);
1179 }
1180
1181 /**
1182 * g_variant_new_signature:
1183 * @signature: a normal C nul-terminated string
1184 * @returns: (transfer none): a floating reference to a new signature #GVariant instance
1185 *
1186 * Creates a D-Bus type signature #GVariant with the contents of
1187 * @string. @string must be a valid D-Bus type signature. Use
1188 * g_variant_is_signature() if you're not sure.
1189 *
1190 * Since: 2.24
1191 **/
1192 GVariant *
1193 g_variant_new_signature (const gchar *signature)
1194 {
1195 g_return_val_if_fail (g_variant_is_signature (signature), NULL);
1196
1197 return g_variant_new_from_trusted (G_VARIANT_TYPE_SIGNATURE,
1198 signature, strlen (signature) + 1);
1199 }
1200
1201 /**
1202 * g_variant_is_signature:
1203 * @string: a normal C nul-terminated string
1204 * @returns: %TRUE if @string is a D-Bus type signature
1205 *
1206 * Determines if a given string is a valid D-Bus type signature. You
1207 * should ensure that a string is a valid D-Bus type signature before
1208 * passing it to g_variant_new_signature().
1209 *
1210 * D-Bus type signatures consist of zero or more definite #GVariantType
1211 * strings in sequence.
1212 *
1213 * Since: 2.24
1214 **/
1215 gboolean
1216 g_variant_is_signature (const gchar *string)
1217 {
1218 g_return_val_if_fail (string != NULL, FALSE);
1219
1220 return g_variant_serialiser_is_signature (string, strlen (string) + 1);
1221 }
1222
1223 /**
1224 * g_variant_get_string:
1225 * @value: a string #GVariant instance
1226 * @length: (allow-none) (default 0) (out): a pointer to a #gsize,
1227 * to store the length
1228 * @returns: (transfer none): the constant string, utf8 encoded
1229 *
1230 * Returns the string value of a #GVariant instance with a string
1231 * type. This includes the types %G_VARIANT_TYPE_STRING,
1232 * %G_VARIANT_TYPE_OBJECT_PATH and %G_VARIANT_TYPE_SIGNATURE.
1233 *
1234 * The string will always be utf8 encoded.
1235 *
1236 * If @length is non-%NULL then the length of the string (in bytes) is
1237 * returned there. For trusted values, this information is already
1238 * known. For untrusted values, a strlen() will be performed.
1239 *
1240 * It is an error to call this function with a @value of any type
1241 * other than those three.
1242 *
1243 * The return value remains valid as long as @value exists.
1244 *
1245 * Since: 2.24
1246 **/
1247 const gchar *
1248 g_variant_get_string (GVariant *value,
1249 gsize *length)
1250 {
1251 gconstpointer data;
1252 gsize size;
1253
1254 g_return_val_if_fail (value != NULL, NULL);
1255 g_return_val_if_fail (
1256 g_variant_is_of_type (value, G_VARIANT_TYPE_STRING) ||
1257 g_variant_is_of_type (value, G_VARIANT_TYPE_OBJECT_PATH) ||
1258 g_variant_is_of_type (value, G_VARIANT_TYPE_SIGNATURE), NULL);
1259
1260 data = g_variant_get_data (value);
1261 size = g_variant_get_size (value);
1262
1263 if (!g_variant_is_trusted (value))
1264 {
1265 switch (g_variant_classify (value))
1266 {
1267 case G_VARIANT_CLASS_STRING:
1268 if (g_variant_serialiser_is_string (data, size))
1269 break;
1270
1271 data = "";
1272 size = 1;
1273 break;
1274
1275 case G_VARIANT_CLASS_OBJECT_PATH:
1276 if (g_variant_serialiser_is_object_path (data, size))
1277 break;
1278
1279 data = "/";
1280 size = 2;
1281 break;
1282
1283 case G_VARIANT_CLASS_SIGNATURE:
1284 if (g_variant_serialiser_is_signature (data, size))
1285 break;
1286
1287 data = "";
1288 size = 1;
1289 break;
1290
1291 default:
1292 g_assert_not_reached ();
1293 }
1294 }
1295
1296 if (length)
1297 *length = size - 1;
1298
1299 return data;
1300 }
1301
1302 /**
1303 * g_variant_dup_string:
1304 * @value: a string #GVariant instance
1305 * @length: (out): a pointer to a #gsize, to store the length
1306 * @returns: (transfer full): a newly allocated string, utf8 encoded
1307 *
1308 * Similar to g_variant_get_string() except that instead of returning
1309 * a constant string, the string is duplicated.
1310 *
1311 * The string will always be utf8 encoded.
1312 *
1313 * The return value must be freed using g_free().
1314 *
1315 * Since: 2.24
1316 **/
1317 gchar *
1318 g_variant_dup_string (GVariant *value,
1319 gsize *length)
1320 {
1321 return g_strdup (g_variant_get_string (value, length));
1322 }
1323
1324 /**
1325 * g_variant_new_strv:
1326 * @strv: (array length=length) (element-type utf8): an array of strings
1327 * @length: the length of @strv, or -1
1328 * @returns: (transfer none): a new floating #GVariant instance
1329 *
1330 * Constructs an array of strings #GVariant from the given array of
1331 * strings.
1332 *
1333 * If @length is -1 then @strv is %NULL-terminated.
1334 *
1335 * Since: 2.24
1336 **/
1337 GVariant *
1338 g_variant_new_strv (const gchar * const *strv,
1339 gssize length)
1340 {
1341 GVariant **strings;
1342 gsize i;
1343
1344 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1345
1346 if (length < 0)
1347 length = g_strv_length ((gchar **) strv);
1348
1349 strings = g_new (GVariant *, length);
1350 for (i = 0; i < length; i++)
1351 strings[i] = g_variant_ref_sink (g_variant_new_string (strv[i]));
1352
1353 return g_variant_new_from_children (G_VARIANT_TYPE_STRING_ARRAY,
1354 strings, length, TRUE);
1355 }
1356
1357 /**
1358 * g_variant_get_strv:
1359 * @value: an array of strings #GVariant
1360 * @length: (out) (allow-none): the length of the result, or %NULL
1361 * @returns: (array length=length zero-terminated=1) (transfer container): an array of constant
1362 * strings
1363 *
1364 * Gets the contents of an array of strings #GVariant. This call
1365 * makes a shallow copy; the return result should be released with
1366 * g_free(), but the individual strings must not be modified.
1367 *
1368 * If @length is non-%NULL then the number of elements in the result
1369 * is stored there. In any case, the resulting array will be
1370 * %NULL-terminated.
1371 *
1372 * For an empty array, @length will be set to 0 and a pointer to a
1373 * %NULL pointer will be returned.
1374 *
1375 * Since: 2.24
1376 **/
1377 const gchar **
1378 g_variant_get_strv (GVariant *value,
1379 gsize *length)
1380 {
1381 const gchar **strv;
1382 gsize n;
1383 gsize i;
1384
1385 TYPE_CHECK (value, G_VARIANT_TYPE_STRING_ARRAY, NULL);
1386
1387 g_variant_get_data (value);
1388 n = g_variant_n_children (value);
1389 strv = g_new (const gchar *, n + 1);
1390
1391 for (i = 0; i < n; i++)
1392 {
1393 GVariant *string;
1394
1395 string = g_variant_get_child_value (value, i);
1396 strv[i] = g_variant_get_string (string, NULL);
1397 g_variant_unref (string);
1398 }
1399 strv[i] = NULL;
1400
1401 if (length)
1402 *length = n;
1403
1404 return strv;
1405 }
1406
1407 /**
1408 * g_variant_dup_strv:
1409 * @value: an array of strings #GVariant
1410 * @length: (out) (allow-none): the length of the result, or %NULL
1411 * @returns: (array length=length zero-terminated=1) (transfer full): an array of strings
1412 *
1413 * Gets the contents of an array of strings #GVariant. This call
1414 * makes a deep copy; the return result should be released with
1415 * g_strfreev().
1416 *
1417 * If @length is non-%NULL then the number of elements in the result
1418 * is stored there. In any case, the resulting array will be
1419 * %NULL-terminated.
1420 *
1421 * For an empty array, @length will be set to 0 and a pointer to a
1422 * %NULL pointer will be returned.
1423 *
1424 * Since: 2.24
1425 **/
1426 gchar **
1427 g_variant_dup_strv (GVariant *value,
1428 gsize *length)
1429 {
1430 gchar **strv;
1431 gsize n;
1432 gsize i;
1433
1434 TYPE_CHECK (value, G_VARIANT_TYPE_STRING_ARRAY, NULL);
1435
1436 n = g_variant_n_children (value);
1437 strv = g_new (gchar *, n + 1);
1438
1439 for (i = 0; i < n; i++)
1440 {
1441 GVariant *string;
1442
1443 string = g_variant_get_child_value (value, i);
1444 strv[i] = g_variant_dup_string (string, NULL);
1445 g_variant_unref (string);
1446 }
1447 strv[i] = NULL;
1448
1449 if (length)
1450 *length = n;
1451
1452 return strv;
1453 }
1454
1455 /**
1456 * g_variant_new_bytestring:
1457 * @string: (array zero-terminated=1): a normal nul-terminated string in no particular encoding
1458 * @returns: (transfer none): a floating reference to a new bytestring #GVariant instance
1459 *
1460 * Creates an array-of-bytes #GVariant with the contents of @string.
1461 * This function is just like g_variant_new_string() except that the
1462 * string need not be valid utf8.
1463 *
1464 * The nul terminator character at the end of the string is stored in
1465 * the array.
1466 *
1467 * Since: 2.26
1468 **/
1469 GVariant *
1470 g_variant_new_bytestring (const gchar *string)
1471 {
1472 g_return_val_if_fail (string != NULL, NULL);
1473
1474 return g_variant_new_from_trusted (G_VARIANT_TYPE_BYTESTRING,
1475 string, strlen (string) + 1);
1476 }
1477
1478 /**
1479 * g_variant_get_bytestring:
1480 * @value: an array-of-bytes #GVariant instance
1481 * @returns: (transfer none) (array zero-terminated=1): the constant string
1482 *
1483 * Returns the string value of a #GVariant instance with an
1484 * array-of-bytes type. The string has no particular encoding.
1485 *
1486 * If the array does not end with a nul terminator character, the empty
1487 * string is returned. For this reason, you can always trust that a
1488 * non-%NULL nul-terminated string will be returned by this function.
1489 *
1490 * If the array contains a nul terminator character somewhere other than
1491 * the last byte then the returned string is the string, up to the first
1492 * such nul character.
1493 *
1494 * It is an error to call this function with a @value that is not an
1495 * array of bytes.
1496 *
1497 * The return value remains valid as long as @value exists.
1498 *
1499 * Since: 2.26
1500 **/
1501 const gchar *
1502 g_variant_get_bytestring (GVariant *value)
1503 {
1504 const gchar *string;
1505 gsize size;
1506
1507 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING, NULL);
1508
1509 /* Won't be NULL since this is an array type */
1510 string = g_variant_get_data (value);
1511 size = g_variant_get_size (value);
1512
1513 if (size && string[size - 1] == '\0')
1514 return string;
1515 else
1516 return "";
1517 }
1518
1519 /**
1520 * g_variant_dup_bytestring:
1521 * @value: an array-of-bytes #GVariant instance
1522 * @length: (out) (allow-none) (default NULL): a pointer to a #gsize, to store
1523 * the length (not including the nul terminator)
1524 * @returns: (transfer full) (array zero-terminated=1): a newly allocated string
1525 *
1526 * Similar to g_variant_get_bytestring() except that instead of
1527 * returning a constant string, the string is duplicated.
1528 *
1529 * The return value must be freed using g_free().
1530 *
1531 * Since: 2.26
1532 **/
1533 gchar *
1534 g_variant_dup_bytestring (GVariant *value,
1535 gsize *length)
1536 {
1537 const gchar *original = g_variant_get_bytestring (value);
1538 gsize size;
1539
1540 /* don't crash in case get_bytestring() had an assert failure */
1541 if (original == NULL)
1542 return NULL;
1543
1544 size = strlen (original);
1545
1546 if (length)
1547 *length = size;
1548
1549 return g_memdup (original, size + 1);
1550 }
1551
1552 /**
1553 * g_variant_new_bytestring_array:
1554 * @strv: (array length=length): an array of strings
1555 * @length: the length of @strv, or -1
1556 * @returns: (transfer none): a new floating #GVariant instance
1557 *
1558 * Constructs an array of bytestring #GVariant from the given array of
1559 * strings.
1560 *
1561 * If @length is -1 then @strv is %NULL-terminated.
1562 *
1563 * Since: 2.26
1564 **/
1565 GVariant *
1566 g_variant_new_bytestring_array (const gchar * const *strv,
1567 gssize length)
1568 {
1569 GVariant **strings;
1570 gsize i;
1571
1572 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1573
1574 if (length < 0)
1575 length = g_strv_length ((gchar **) strv);
1576
1577 strings = g_new (GVariant *, length);
1578 for (i = 0; i < length; i++)
1579 strings[i] = g_variant_ref_sink (g_variant_new_bytestring (strv[i]));
1580
1581 return g_variant_new_from_children (G_VARIANT_TYPE_BYTESTRING_ARRAY,
1582 strings, length, TRUE);
1583 }
1584
1585 /**
1586 * g_variant_get_bytestring_array:
1587 * @value: an array of array of bytes #GVariant ('aay')
1588 * @length: (out) (allow-none): the length of the result, or %NULL
1589 * @returns: (array length=length) (transfer container): an array of constant strings
1590 *
1591 * Gets the contents of an array of array of bytes #GVariant. This call
1592 * makes a shallow copy; the return result should be released with
1593 * g_free(), but the individual strings must not be modified.
1594 *
1595 * If @length is non-%NULL then the number of elements in the result is
1596 * stored there. In any case, the resulting array will be
1597 * %NULL-terminated.
1598 *
1599 * For an empty array, @length will be set to 0 and a pointer to a
1600 * %NULL pointer will be returned.
1601 *
1602 * Since: 2.26
1603 **/
1604 const gchar **
1605 g_variant_get_bytestring_array (GVariant *value,
1606 gsize *length)
1607 {
1608 const gchar **strv;
1609 gsize n;
1610 gsize i;
1611
1612 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL);
1613
1614 g_variant_get_data (value);
1615 n = g_variant_n_children (value);
1616 strv = g_new (const gchar *, n + 1);
1617
1618 for (i = 0; i < n; i++)
1619 {
1620 GVariant *string;
1621
1622 string = g_variant_get_child_value (value, i);
1623 strv[i] = g_variant_get_bytestring (string);
1624 g_variant_unref (string);
1625 }
1626 strv[i] = NULL;
1627
1628 if (length)
1629 *length = n;
1630
1631 return strv;
1632 }
1633
1634 /**
1635 * g_variant_dup_bytestring_array:
1636 * @value: an array of array of bytes #GVariant ('aay')
1637 * @length: (out) (allow-none): the length of the result, or %NULL
1638 * @returns: (array length=length) (transfer full): an array of strings
1639 *
1640 * Gets the contents of an array of array of bytes #GVariant. This call
1641 * makes a deep copy; the return result should be released with
1642 * g_strfreev().
1643 *
1644 * If @length is non-%NULL then the number of elements in the result is
1645 * stored there. In any case, the resulting array will be
1646 * %NULL-terminated.
1647 *
1648 * For an empty array, @length will be set to 0 and a pointer to a
1649 * %NULL pointer will be returned.
1650 *
1651 * Since: 2.26
1652 **/
1653 gchar **
1654 g_variant_dup_bytestring_array (GVariant *value,
1655 gsize *length)
1656 {
1657 gchar **strv;
1658 gsize n;
1659 gsize i;
1660
1661 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL);
1662
1663 g_variant_get_data (value);
1664 n = g_variant_n_children (value);
1665 strv = g_new (gchar *, n + 1);
1666
1667 for (i = 0; i < n; i++)
1668 {
1669 GVariant *string;
1670
1671 string = g_variant_get_child_value (value, i);
1672 strv[i] = g_variant_dup_bytestring (string, NULL);
1673 g_variant_unref (string);
1674 }
1675 strv[i] = NULL;
1676
1677 if (length)
1678 *length = n;
1679
1680 return strv;
1681 }
1682
1683 /* Type checking and querying {{{1 */
1684 /**
1685 * g_variant_get_type:
1686 * @value: a #GVariant
1687 * @returns: a #GVariantType
1688 *
1689 * Determines the type of @value.
1690 *
1691 * The return value is valid for the lifetime of @value and must not
1692 * be freed.
1693 *
1694 * Since: 2.24
1695 **/
1696 const GVariantType *
1697 g_variant_get_type (GVariant *value)
1698 {
1699 GVariantTypeInfo *type_info;
1700
1701 g_return_val_if_fail (value != NULL, NULL);
1702
1703 type_info = g_variant_get_type_info (value);
1704
1705 return (GVariantType *) g_variant_type_info_get_type_string (type_info);
1706 }
1707
1708 /**
1709 * g_variant_get_type_string:
1710 * @value: a #GVariant
1711 * @returns: the type string for the type of @value
1712 *
1713 * Returns the type string of @value. Unlike the result of calling
1714 * g_variant_type_peek_string(), this string is nul-terminated. This
1715 * string belongs to #GVariant and must not be freed.
1716 *
1717 * Since: 2.24
1718 **/
1719 const gchar *
1720 g_variant_get_type_string (GVariant *value)
1721 {
1722 GVariantTypeInfo *type_info;
1723
1724 g_return_val_if_fail (value != NULL, NULL);
1725
1726 type_info = g_variant_get_type_info (value);
1727
1728 return g_variant_type_info_get_type_string (type_info);
1729 }
1730
1731 /**
1732 * g_variant_is_of_type:
1733 * @value: a #GVariant instance
1734 * @type: a #GVariantType
1735 * @returns: %TRUE if the type of @value matches @type
1736 *
1737 * Checks if a value has a type matching the provided type.
1738 *
1739 * Since: 2.24
1740 **/
1741 gboolean
1742 g_variant_is_of_type (GVariant *value,
1743 const GVariantType *type)
1744 {
1745 return g_variant_type_is_subtype_of (g_variant_get_type (value), type);
1746 }
1747
1748 /**
1749 * g_variant_is_container:
1750 * @value: a #GVariant instance
1751 * @returns: %TRUE if @value is a container
1752 *
1753 * Checks if @value is a container.
1754 */
1755 gboolean
1756 g_variant_is_container (GVariant *value)
1757 {
1758 return g_variant_type_is_container (g_variant_get_type (value));
1759 }
1760
1761
1762 /**
1763 * g_variant_classify:
1764 * @value: a #GVariant
1765 * @returns: the #GVariantClass of @value
1766 *
1767 * Classifies @value according to its top-level type.
1768 *
1769 * Since: 2.24
1770 **/
1771 /**
1772 * GVariantClass:
1773 * @G_VARIANT_CLASS_BOOLEAN: The #GVariant is a boolean.
1774 * @G_VARIANT_CLASS_BYTE: The #GVariant is a byte.
1775 * @G_VARIANT_CLASS_INT16: The #GVariant is a signed 16 bit integer.
1776 * @G_VARIANT_CLASS_UINT16: The #GVariant is an unsigned 16 bit integer.
1777 * @G_VARIANT_CLASS_INT32: The #GVariant is a signed 32 bit integer.
1778 * @G_VARIANT_CLASS_UINT32: The #GVariant is an unsigned 32 bit integer.
1779 * @G_VARIANT_CLASS_INT64: The #GVariant is a signed 64 bit integer.
1780 * @G_VARIANT_CLASS_UINT64: The #GVariant is an unsigned 64 bit integer.
1781 * @G_VARIANT_CLASS_HANDLE: The #GVariant is a file handle index.
1782 * @G_VARIANT_CLASS_DOUBLE: The #GVariant is a double precision floating
1783 * point value.
1784 * @G_VARIANT_CLASS_STRING: The #GVariant is a normal string.
1785 * @G_VARIANT_CLASS_OBJECT_PATH: The #GVariant is a D-Bus object path
1786 * string.
1787 * @G_VARIANT_CLASS_SIGNATURE: The #GVariant is a D-Bus signature string.
1788 * @G_VARIANT_CLASS_VARIANT: The #GVariant is a variant.
1789 * @G_VARIANT_CLASS_MAYBE: The #GVariant is a maybe-typed value.
1790 * @G_VARIANT_CLASS_ARRAY: The #GVariant is an array.
1791 * @G_VARIANT_CLASS_TUPLE: The #GVariant is a tuple.
1792 * @G_VARIANT_CLASS_DICT_ENTRY: The #GVariant is a dictionary entry.
1793 *
1794 * The range of possible top-level types of #GVariant instances.
1795 *
1796 * Since: 2.24
1797 **/
1798 GVariantClass
1799 g_variant_classify (GVariant *value)
1800 {
1801 g_return_val_if_fail (value != NULL, 0);
1802
1803 return *g_variant_get_type_string (value);
1804 }
1805
1806 /* Pretty printer {{{1 */
1807 /* This function is not introspectable because if @string is NULL,
1808 @returns is (transfer full), otherwise it is (transfer none), which
1809 is not supported by GObjectIntrospection */
1810 /**
1811 * g_variant_print_string: (skip)
1812 * @value: a #GVariant
1813 * @string: (allow-none) (default NULL): a #GString, or %NULL
1814 * @type_annotate: %TRUE if type information should be included in
1815 * the output
1816 * @returns: a #GString containing the string
1817 *
1818 * Behaves as g_variant_print(), but operates on a #GString.
1819 *
1820 * If @string is non-%NULL then it is appended to and returned. Else,
1821 * a new empty #GString is allocated and it is returned.
1822 *
1823 * Since: 2.24
1824 **/
1825 GString *
1826 g_variant_print_string (GVariant *value,
1827 GString *string,
1828 gboolean type_annotate)
1829 {
1830 if G_UNLIKELY (string == NULL)
1831 string = g_string_new (NULL);
1832
1833 switch (g_variant_classify (value))
1834 {
1835 case G_VARIANT_CLASS_MAYBE:
1836 if (type_annotate)
1837 g_string_append_printf (string, "@%s ",
1838 g_variant_get_type_string (value));
1839
1840 if (g_variant_n_children (value))
1841 {
1842 gchar *printed_child;
1843 GVariant *element;
1844
1845 /* Nested maybes:
1846 *
1847 * Consider the case of the type "mmi". In this case we could
1848 * write "just just 4", but "4" alone is totally unambiguous,
1849 * so we try to drop "just" where possible.
1850 *
1851 * We have to be careful not to always drop "just", though,
1852 * since "nothing" needs to be distinguishable from "just
1853 * nothing". The case where we need to ensure we keep the
1854 * "just" is actually exactly the case where we have a nested
1855 * Nothing.
1856 *
1857 * Instead of searching for that nested Nothing, we just print
1858 * the contained value into a separate string and see if we
1859 * end up with "nothing" at the end of it. If so, we need to
1860 * add "just" at our level.
1861 */
1862 element = g_variant_get_child_value (value, 0);
1863 printed_child = g_variant_print (element, FALSE);
1864 g_variant_unref (element);
1865
1866 if (g_str_has_suffix (printed_child, "nothing"))
1867 g_string_append (string, "just ");
1868 g_string_append (string, printed_child);
1869 g_free (printed_child);
1870 }
1871 else
1872 g_string_append (string, "nothing");
1873
1874 break;
1875
1876 case G_VARIANT_CLASS_ARRAY:
1877 /* it's an array so the first character of the type string is 'a'
1878 *
1879 * if the first two characters are 'ay' then it's a bytestring.
1880 * under certain conditions we print those as strings.
1881 */
1882 if (g_variant_get_type_string (value)[1] == 'y')
1883 {
1884 const gchar *str;
1885 gsize size;
1886 gsize i;
1887
1888 /* first determine if it is a byte string.
1889 * that's when there's a single nul character: at the end.
1890 */
1891 str = g_variant_get_data (value);
1892 size = g_variant_get_size (value);
1893
1894 for (i = 0; i < size; i++)
1895 if (str[i] == '\0')
1896 break;
1897
1898 /* first nul byte is the last byte -> it's a byte string. */
1899 if (i == size - 1)
1900 {
1901 gchar *escaped = g_strescape (str, NULL);
1902
1903 /* use double quotes only if a ' is in the string */
1904 if (strchr (str, '\''))
1905 g_string_append_printf (string, "b\"%s\"", escaped);
1906 else
1907 g_string_append_printf (string, "b'%s'", escaped);
1908
1909 g_free (escaped);
1910 break;
1911 }
1912
1913 else
1914 /* fall through and handle normally... */;
1915 }
1916
1917 /*
1918 * if the first two characters are 'a{' then it's an array of
1919 * dictionary entries (ie: a dictionary) so we print that
1920 * differently.
1921 */
1922 if (g_variant_get_type_string (value)[1] == '{')
1923 /* dictionary */
1924 {
1925 const gchar *comma = "";
1926 gsize n, i;
1927
1928 if ((n = g_variant_n_children (value)) == 0)
1929 {
1930 if (type_annotate)
1931 g_string_append_printf (string, "@%s ",
1932 g_variant_get_type_string (value));
1933 g_string_append (string, "{}");
1934 break;
1935 }
1936
1937 g_string_append_c (string, '{');
1938 for (i = 0; i < n; i++)
1939 {
1940 GVariant *entry, *key, *val;
1941
1942 g_string_append (string, comma);
1943 comma = ", ";
1944
1945 entry = g_variant_get_child_value (value, i);
1946 key = g_variant_get_child_value (entry, 0);
1947 val = g_variant_get_child_value (entry, 1);
1948 g_variant_unref (entry);
1949
1950 g_variant_print_string (key, string, type_annotate);
1951 g_variant_unref (key);
1952 g_string_append (string, ": ");
1953 g_variant_print_string (val, string, type_annotate);
1954 g_variant_unref (val);
1955 type_annotate = FALSE;
1956 }
1957 g_string_append_c (string, '}');
1958 }
1959 else
1960 /* normal (non-dictionary) array */
1961 {
1962 const gchar *comma = "";
1963 gsize n, i;
1964
1965 if ((n = g_variant_n_children (value)) == 0)
1966 {
1967 if (type_annotate)
1968 g_string_append_printf (string, "@%s ",
1969 g_variant_get_type_string (value));
1970 g_string_append (string, "[]");
1971 break;
1972 }
1973
1974 g_string_append_c (string, '[');
1975 for (i = 0; i < n; i++)
1976 {
1977 GVariant *element;
1978
1979 g_string_append (string, comma);
1980 comma = ", ";
1981
1982 element = g_variant_get_child_value (value, i);
1983
1984 g_variant_print_string (element, string, type_annotate);
1985 g_variant_unref (element);
1986 type_annotate = FALSE;
1987 }
1988 g_string_append_c (string, ']');
1989 }
1990
1991 break;
1992
1993 case G_VARIANT_CLASS_TUPLE:
1994 {
1995 gsize n, i;
1996
1997 n = g_variant_n_children (value);
1998
1999 g_string_append_c (string, '(');
2000 for (i = 0; i < n; i++)
2001 {
2002 GVariant *element;
2003
2004 element = g_variant_get_child_value (value, i);
2005 g_variant_print_string (element, string, type_annotate);
2006 g_string_append (string, ", ");
2007 g_variant_unref (element);
2008 }
2009
2010 /* for >1 item: remove final ", "
2011 * for 1 item: remove final " ", but leave the ","
2012 * for 0 items: there is only "(", so remove nothing
2013 */
2014 g_string_truncate (string, string->len - (n > 0) - (n > 1));
2015 g_string_append_c (string, ')');
2016 }
2017 break;
2018
2019 case G_VARIANT_CLASS_DICT_ENTRY:
2020 {
2021 GVariant *element;
2022
2023 g_string_append_c (string, '{');
2024
2025 element = g_variant_get_child_value (value, 0);
2026 g_variant_print_string (element, string, type_annotate);
2027 g_variant_unref (element);
2028
2029 g_string_append (string, ", ");
2030
2031 element = g_variant_get_child_value (value, 1);
2032 g_variant_print_string (element, string, type_annotate);
2033 g_variant_unref (element);
2034
2035 g_string_append_c (string, '}');
2036 }
2037 break;
2038
2039 case G_VARIANT_CLASS_VARIANT:
2040 {
2041 GVariant *child = g_variant_get_variant (value);
2042
2043 /* Always annotate types in nested variants, because they are
2044 * (by nature) of variable type.
2045 */
2046 g_string_append_c (string, '<');
2047 g_variant_print_string (child, string, TRUE);
2048 g_string_append_c (string, '>');
2049
2050 g_variant_unref (child);
2051 }
2052 break;
2053
2054 case G_VARIANT_CLASS_BOOLEAN:
2055 if (g_variant_get_boolean (value))
2056 g_string_append (string, "true");
2057 else
2058 g_string_append (string, "false");
2059 break;
2060
2061 case G_VARIANT_CLASS_STRING:
2062 {
2063 const gchar *str = g_variant_get_string (value, NULL);
2064 gunichar quote = strchr (str, '\'') ? '"' : '\'';
2065
2066 g_string_append_c (string, quote);
2067
2068 while (*str)
2069 {
2070 gunichar c = g_utf8_get_char (str);
2071
2072 if (c == quote || c == '\\')
2073 g_string_append_c (string, '\\');
2074
2075 if (g_unichar_isprint (c))
2076 g_string_append_unichar (string, c);
2077
2078 else
2079 {
2080 g_string_append_c (string, '\\');
2081 if (c < 0x10000)
2082 switch (c)
2083 {
2084 case '\a':
2085 g_string_append_c (string, 'a');
2086 break;
2087
2088 case '\b':
2089 g_string_append_c (string, 'b');
2090 break;
2091
2092 case '\f':
2093 g_string_append_c (string, 'f');
2094 break;
2095
2096 case '\n':
2097 g_string_append_c (string, 'n');
2098 break;
2099
2100 case '\r':
2101 g_string_append_c (string, 'r');
2102 break;
2103
2104 case '\t':
2105 g_string_append_c (string, 't');
2106 break;
2107
2108 case '\v':
2109 g_string_append_c (string, 'v');
2110 break;
2111
2112 default:
2113 g_string_append_printf (string, "u%04x", c);
2114 break;
2115 }
2116 else
2117 g_string_append_printf (string, "U%08x", c);
2118 }
2119
2120 str = g_utf8_next_char (str);
2121 }
2122
2123 g_string_append_c (string, quote);
2124 }
2125 break;
2126
2127 case G_VARIANT_CLASS_BYTE:
2128 if (type_annotate)
2129 g_string_append (string, "byte ");
2130 g_string_append_printf (string, "0x%02x",
2131 g_variant_get_byte (value));
2132 break;
2133
2134 case G_VARIANT_CLASS_INT16:
2135 if (type_annotate)
2136 g_string_append (string, "int16 ");
2137 g_string_append_printf (string, "%"G_GINT16_FORMAT,
2138 g_variant_get_int16 (value));
2139 break;
2140
2141 case G_VARIANT_CLASS_UINT16:
2142 if (type_annotate)
2143 g_string_append (string, "uint16 ");
2144 g_string_append_printf (string, "%"G_GUINT16_FORMAT,
2145 g_variant_get_uint16 (value));
2146 break;
2147
2148 case G_VARIANT_CLASS_INT32:
2149 /* Never annotate this type because it is the default for numbers
2150 * (and this is a *pretty* printer)
2151 */
2152 g_string_append_printf (string, "%"G_GINT32_FORMAT,
2153 g_variant_get_int32 (value));
2154 break;
2155
2156 case G_VARIANT_CLASS_HANDLE:
2157 if (type_annotate)
2158 g_string_append (string, "handle ");
2159 g_string_append_printf (string, "%"G_GINT32_FORMAT,
2160 g_variant_get_handle (value));
2161 break;
2162
2163 case G_VARIANT_CLASS_UINT32:
2164 if (type_annotate)
2165 g_string_append (string, "uint32 ");
2166 g_string_append_printf (string, "%"G_GUINT32_FORMAT,
2167 g_variant_get_uint32 (value));
2168 break;
2169
2170 case G_VARIANT_CLASS_INT64:
2171 if (type_annotate)
2172 g_string_append (string, "int64 ");
2173 g_string_append_printf (string, "%"G_GINT64_FORMAT,
2174 g_variant_get_int64 (value));
2175 break;
2176
2177 case G_VARIANT_CLASS_UINT64:
2178 if (type_annotate)
2179 g_string_append (string, "uint64 ");
2180 g_string_append_printf (string, "%"G_GUINT64_FORMAT,
2181 g_variant_get_uint64 (value));
2182 break;
2183
2184 case G_VARIANT_CLASS_DOUBLE:
2185 {
2186 gchar buffer[100];
2187 gint i;
2188
2189 g_ascii_dtostr (buffer, sizeof buffer, g_variant_get_double (value));
2190
2191 for (i = 0; buffer[i]; i++)
2192 if (buffer[i] == '.' || buffer[i] == 'e' ||
2193 buffer[i] == 'n' || buffer[i] == 'N')
2194 break;
2195
2196 /* if there is no '.' or 'e' in the float then add one */
2197 if (buffer[i] == '\0')
2198 {
2199 buffer[i++] = '.';
2200 buffer[i++] = '0';
2201 buffer[i++] = '\0';
2202 }
2203
2204 g_string_append (string, buffer);
2205 }
2206 break;
2207
2208 case G_VARIANT_CLASS_OBJECT_PATH:
2209 if (type_annotate)
2210 g_string_append (string, "objectpath ");
2211 g_string_append_printf (string, "\'%s\'",
2212 g_variant_get_string (value, NULL));
2213 break;
2214
2215 case G_VARIANT_CLASS_SIGNATURE:
2216 if (type_annotate)
2217 g_string_append (string, "signature ");
2218 g_string_append_printf (string, "\'%s\'",
2219 g_variant_get_string (value, NULL));
2220 break;
2221
2222 default:
2223 g_assert_not_reached ();
2224 }
2225
2226 return string;
2227 }
2228
2229 /**
2230 * g_variant_print:
2231 * @value: a #GVariant
2232 * @type_annotate: %TRUE if type information should be included in
2233 * the output
2234 * @returns: (transfer full): a newly-allocated string holding the result.
2235 *
2236 * Pretty-prints @value in the format understood by g_variant_parse().
2237 *
2238 * The format is described <link linkend='gvariant-text'>here</link>.
2239 *
2240 * If @type_annotate is %TRUE, then type information is included in
2241 * the output.
2242 */
2243 gchar *
2244 g_variant_print (GVariant *value,
2245 gboolean type_annotate)
2246 {
2247 return g_string_free (g_variant_print_string (value, NULL, type_annotate),
2248 FALSE);
2249 };
2250
2251 /* Hash, Equal, Compare {{{1 */
2252 /**
2253 * g_variant_hash:
2254 * @value: (type GVariant): a basic #GVariant value as a #gconstpointer
2255 * @returns: a hash value corresponding to @value
2256 *
2257 * Generates a hash value for a #GVariant instance.
2258 *
2259 * The output of this function is guaranteed to be the same for a given
2260 * value only per-process. It may change between different processor
2261 * architectures or even different versions of GLib. Do not use this
2262 * function as a basis for building protocols or file formats.
2263 *
2264 * The type of @value is #gconstpointer only to allow use of this
2265 * function with #GHashTable. @value must be a #GVariant.
2266 *
2267 * Since: 2.24
2268 **/
2269 guint
2270 g_variant_hash (gconstpointer value_)
2271 {
2272 GVariant *value = (GVariant *) value_;
2273
2274 switch (g_variant_classify (value))
2275 {
2276 case G_VARIANT_CLASS_STRING:
2277 case G_VARIANT_CLASS_OBJECT_PATH:
2278 case G_VARIANT_CLASS_SIGNATURE:
2279 return g_str_hash (g_variant_get_string (value, NULL));
2280
2281 case G_VARIANT_CLASS_BOOLEAN:
2282 /* this is a very odd thing to hash... */
2283 return g_variant_get_boolean (value);
2284
2285 case G_VARIANT_CLASS_BYTE:
2286 return g_variant_get_byte (value);
2287
2288 case G_VARIANT_CLASS_INT16:
2289 case G_VARIANT_CLASS_UINT16:
2290 {
2291 const guint16 *ptr;
2292
2293 ptr = g_variant_get_data (value);
2294
2295 if (ptr)
2296 return *ptr;
2297 else
2298 return 0;
2299 }
2300
2301 case G_VARIANT_CLASS_INT32:
2302 case G_VARIANT_CLASS_UINT32:
2303 case G_VARIANT_CLASS_HANDLE:
2304 {
2305 const guint *ptr;
2306
2307 ptr = g_variant_get_data (value);
2308
2309 if (ptr)
2310 return *ptr;
2311 else
2312 return 0;
2313 }
2314
2315 case G_VARIANT_CLASS_INT64:
2316 case G_VARIANT_CLASS_UINT64:
2317 case G_VARIANT_CLASS_DOUBLE:
2318 /* need a separate case for these guys because otherwise
2319 * performance could be quite bad on big endian systems
2320 */
2321 {
2322 const guint *ptr;
2323
2324 ptr = g_variant_get_data (value);
2325
2326 if (ptr)
2327 return ptr[0] + ptr[1];
2328 else
2329 return 0;
2330 }
2331
2332 default:
2333 g_return_val_if_fail (!g_variant_is_container (value), 0);
2334 g_assert_not_reached ();
2335 }
2336 }
2337
2338 /**
2339 * g_variant_equal:
2340 * @one: (type GVariant): a #GVariant instance
2341 * @two: (type GVariant): a #GVariant instance
2342 * @returns: %TRUE if @one and @two are equal
2343 *
2344 * Checks if @one and @two have the same type and value.
2345 *
2346 * The types of @one and @two are #gconstpointer only to allow use of
2347 * this function with #GHashTable. They must each be a #GVariant.
2348 *
2349 * Since: 2.24
2350 **/
2351 gboolean
2352 g_variant_equal (gconstpointer one,
2353 gconstpointer two)
2354 {
2355 gboolean equal;
2356
2357 g_return_val_if_fail (one != NULL && two != NULL, FALSE);
2358
2359 if (g_variant_get_type_info ((GVariant *) one) !=
2360 g_variant_get_type_info ((GVariant *) two))
2361 return FALSE;
2362
2363 /* if both values are trusted to be in their canonical serialised form
2364 * then a simple memcmp() of their serialised data will answer the
2365 * question.
2366 *
2367 * if not, then this might generate a false negative (since it is
2368 * possible for two different byte sequences to represent the same
2369 * value). for now we solve this by pretty-printing both values and
2370 * comparing the result.
2371 */
2372 if (g_variant_is_trusted ((GVariant *) one) &&
2373 g_variant_is_trusted ((GVariant *) two))
2374 {
2375 gconstpointer data_one, data_two;
2376 gsize size_one, size_two;
2377
2378 size_one = g_variant_get_size ((GVariant *) one);
2379 size_two = g_variant_get_size ((GVariant *) two);
2380
2381 if (size_one != size_two)
2382 return FALSE;
2383
2384 data_one = g_variant_get_data ((GVariant *) one);
2385 data_two = g_variant_get_data ((GVariant *) two);
2386
2387 equal = memcmp (data_one, data_two, size_one) == 0;
2388 }
2389 else
2390 {
2391 gchar *strone, *strtwo;
2392
2393 strone = g_variant_print ((GVariant *) one, FALSE);
2394 strtwo = g_variant_print ((GVariant *) two, FALSE);
2395 equal = strcmp (strone, strtwo) == 0;
2396 g_free (strone);
2397 g_free (strtwo);
2398 }
2399
2400 return equal;
2401 }
2402
2403 /**
2404 * g_variant_compare:
2405 * @one: (type GVariant): a basic-typed #GVariant instance
2406 * @two: (type GVariant): a #GVariant instance of the same type
2407 * @returns: negative value if a < b;
2408 * zero if a = b;
2409 * positive value if a > b.
2410 *
2411 * Compares @one and @two.
2412 *
2413 * The types of @one and @two are #gconstpointer only to allow use of
2414 * this function with #GTree, #GPtrArray, etc. They must each be a
2415 * #GVariant.
2416 *
2417 * Comparison is only defined for basic types (ie: booleans, numbers,
2418 * strings). For booleans, %FALSE is less than %TRUE. Numbers are
2419 * ordered in the usual way. Strings are in ASCII lexographical order.
2420 *
2421 * It is a programmer error to attempt to compare container values or
2422 * two values that have types that are not exactly equal. For example,
2423 * you can not compare a 32-bit signed integer with a 32-bit unsigned
2424 * integer. Also note that this function is not particularly
2425 * well-behaved when it comes to comparison of doubles; in particular,
2426 * the handling of incomparable values (ie: NaN) is undefined.
2427 *
2428 * If you only require an equality comparison, g_variant_equal() is more
2429 * general.
2430 *
2431 * Since: 2.26
2432 **/
2433 gint
2434 g_variant_compare (gconstpointer one,
2435 gconstpointer two)
2436 {
2437 GVariant *a = (GVariant *) one;
2438 GVariant *b = (GVariant *) two;
2439
2440 g_return_val_if_fail (g_variant_classify (a) == g_variant_classify (b), 0);
2441
2442 switch (g_variant_classify (a))
2443 {
2444 case G_VARIANT_CLASS_BYTE:
2445 return ((gint) g_variant_get_byte (a)) -
2446 ((gint) g_variant_get_byte (b));
2447
2448 case G_VARIANT_CLASS_INT16:
2449 return ((gint) g_variant_get_int16 (a)) -
2450 ((gint) g_variant_get_int16 (b));
2451
2452 case G_VARIANT_CLASS_UINT16:
2453 return ((gint) g_variant_get_uint16 (a)) -
2454 ((gint) g_variant_get_uint16 (b));
2455
2456 case G_VARIANT_CLASS_INT32:
2457 {
2458 gint32 a_val = g_variant_get_int32 (a);
2459 gint32 b_val = g_variant_get_int32 (b);
2460
2461 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2462 }
2463
2464 case G_VARIANT_CLASS_UINT32:
2465 {
2466 guint32 a_val = g_variant_get_uint32 (a);
2467 guint32 b_val = g_variant_get_uint32 (b);
2468
2469 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2470 }
2471
2472 case G_VARIANT_CLASS_INT64:
2473 {
2474 gint64 a_val = g_variant_get_int64 (a);
2475 gint64 b_val = g_variant_get_int64 (b);
2476
2477 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2478 }
2479
2480 case G_VARIANT_CLASS_UINT64:
2481 {
2482 guint64 a_val = g_variant_get_int32 (a);
2483 guint64 b_val = g_variant_get_int32 (b);
2484
2485 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2486 }
2487
2488 case G_VARIANT_CLASS_DOUBLE:
2489 {
2490 gdouble a_val = g_variant_get_double (a);
2491 gdouble b_val = g_variant_get_double (b);
2492
2493 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2494 }
2495
2496 case G_VARIANT_CLASS_STRING:
2497 case G_VARIANT_CLASS_OBJECT_PATH:
2498 case G_VARIANT_CLASS_SIGNATURE:
2499 return strcmp (g_variant_get_string (a, NULL),
2500 g_variant_get_string (b, NULL));
2501
2502 default:
2503 g_return_val_if_fail (!g_variant_is_container (a), 0);
2504 g_assert_not_reached ();
2505 }
2506 }
2507
2508 /* GVariantIter {{{1 */
2509 /**
2510 * GVariantIter:
2511 *
2512 * #GVariantIter is an opaque data structure and can only be accessed
2513 * using the following functions.
2514 **/
2515 struct stack_iter
2516 {
2517 GVariant *value;
2518 gssize n, i;
2519
2520 const gchar *loop_format;
2521
2522 gsize padding[3];
2523 gsize magic;
2524 };
2525
2526 G_STATIC_ASSERT (sizeof (struct stack_iter) <= sizeof (GVariantIter));
2527
2528 struct heap_iter
2529 {
2530 struct stack_iter iter;
2531
2532 GVariant *value_ref;
2533 gsize magic;
2534 };
2535
2536 #define GVSI(i) ((struct stack_iter *) (i))
2537 #define GVHI(i) ((struct heap_iter *) (i))
2538 #define GVSI_MAGIC ((gsize) 3579507750u)
2539 #define GVHI_MAGIC ((gsize) 1450270775u)
2540 #define is_valid_iter(i) (i != NULL && \
2541 GVSI(i)->magic == GVSI_MAGIC)
2542 #define is_valid_heap_iter(i) (GVHI(i)->magic == GVHI_MAGIC && \
2543 is_valid_iter(i))
2544
2545 /**
2546 * g_variant_iter_new:
2547 * @value: a container #GVariant
2548 * @returns: (transfer full): a new heap-allocated #GVariantIter
2549 *
2550 * Creates a heap-allocated #GVariantIter for iterating over the items
2551 * in @value.
2552 *
2553 * Use g_variant_iter_free() to free the return value when you no longer
2554 * need it.
2555 *
2556 * A reference is taken to @value and will be released only when
2557 * g_variant_iter_free() is called.
2558 *
2559 * Since: 2.24
2560 **/
2561 GVariantIter *
2562 g_variant_iter_new (GVariant *value)
2563 {
2564 GVariantIter *iter;
2565
2566 iter = (GVariantIter *) g_slice_new (struct heap_iter);
2567 #ifdef GSTREAMER_LITE
2568 if (iter == NULL) {
2569 return NULL;
2570 }
2571 #endif // GSTREAMER_LITE
2572 GVHI(iter)->value_ref = g_variant_ref (value);
2573 GVHI(iter)->magic = GVHI_MAGIC;
2574
2575 g_variant_iter_init (iter, value);
2576
2577 return iter;
2578 }
2579
2580 /**
2581 * g_variant_iter_init: (skip)
2582 * @iter: a pointer to a #GVariantIter
2583 * @value: a container #GVariant
2584 * @returns: the number of items in @value
2585 *
2586 * Initialises (without allocating) a #GVariantIter. @iter may be
2587 * completely uninitialised prior to this call; its old value is
2588 * ignored.
2589 *
2590 * The iterator remains valid for as long as @value exists, and need not
2591 * be freed in any way.
2592 *
2593 * Since: 2.24
2594 **/
2595 gsize
2596 g_variant_iter_init (GVariantIter *iter,
2597 GVariant *value)
2598 {
2599 GVSI(iter)->magic = GVSI_MAGIC;
2600 GVSI(iter)->value = value;
2601 GVSI(iter)->n = g_variant_n_children (value);
2602 GVSI(iter)->i = -1;
2603 GVSI(iter)->loop_format = NULL;
2604
2605 return GVSI(iter)->n;
2606 }
2607
2608 /**
2609 * g_variant_iter_copy:
2610 * @iter: a #GVariantIter
2611 * @returns: (transfer full): a new heap-allocated #GVariantIter
2612 *
2613 * Creates a new heap-allocated #GVariantIter to iterate over the
2614 * container that was being iterated over by @iter. Iteration begins on
2615 * the new iterator from the current position of the old iterator but
2616 * the two copies are independent past that point.
2617 *
2618 * Use g_variant_iter_free() to free the return value when you no longer
2619 * need it.
2620 *
2621 * A reference is taken to the container that @iter is iterating over
2622 * and will be releated only when g_variant_iter_free() is called.
2623 *
2624 * Since: 2.24
2625 **/
2626 GVariantIter *
2627 g_variant_iter_copy (GVariantIter *iter)
2628 {
2629 GVariantIter *copy;
2630
2631 #ifdef GSTREAMER_LITE
2632 if (iter == NULL) {
2633 return NULL;
2634 }
2635 #endif // GSTREAMER_LITE
2636
2637 g_return_val_if_fail (is_valid_iter (iter), 0);
2638
2639 copy = g_variant_iter_new (GVSI(iter)->value);
2640 GVSI(copy)->i = GVSI(iter)->i;
2641
2642 return copy;
2643 }
2644
2645 /**
2646 * g_variant_iter_n_children:
2647 * @iter: a #GVariantIter
2648 * @returns: the number of children in the container
2649 *
2650 * Queries the number of child items in the container that we are
2651 * iterating over. This is the total number of items -- not the number
2652 * of items remaining.
2653 *
2654 * This function might be useful for preallocation of arrays.
2655 *
2656 * Since: 2.24
2657 **/
2658 gsize
2659 g_variant_iter_n_children (GVariantIter *iter)
2660 {
2661 g_return_val_if_fail (is_valid_iter (iter), 0);
2662
2663 return GVSI(iter)->n;
2664 }
2665
2666 /**
2667 * g_variant_iter_free:
2668 * @iter: (transfer full): a heap-allocated #GVariantIter
2669 *
2670 * Frees a heap-allocated #GVariantIter. Only call this function on
2671 * iterators that were returned by g_variant_iter_new() or
2672 * g_variant_iter_copy().
2673 *
2674 * Since: 2.24
2675 **/
2676 void
2677 g_variant_iter_free (GVariantIter *iter)
2678 {
2679 g_return_if_fail (is_valid_heap_iter (iter));
2680
2681 g_variant_unref (GVHI(iter)->value_ref);
2682 GVHI(iter)->magic = 0;
2683
2684 g_slice_free (struct heap_iter, GVHI(iter));
2685 }
2686
2687 /**
2688 * g_variant_iter_next_value:
2689 * @iter: a #GVariantIter
2690 * @returns: (allow-none) (transfer full): a #GVariant, or %NULL
2691 *
2692 * Gets the next item in the container. If no more items remain then
2693 * %NULL is returned.
2694 *
2695 * Use g_variant_unref() to drop your reference on the return value when
2696 * you no longer need it.
2697 *
2698 * <example>
2699 * <title>Iterating with g_variant_iter_next_value()</title>
2700 * <programlisting>
2701 * /<!-- -->* recursively iterate a container *<!-- -->/
2702 * void
2703 * iterate_container_recursive (GVariant *container)
2704 * {
2705 * GVariantIter iter;
2706 * GVariant *child;
2707 *
2708 * g_variant_iter_init (&iter, dictionary);
2709 * while ((child = g_variant_iter_next_value (&iter)))
2710 * {
2711 * g_print ("type '%s'\n", g_variant_get_type_string (child));
2712 *
2713 * if (g_variant_is_container (child))
2714 * iterate_container_recursive (child);
2715 *
2716 * g_variant_unref (child);
2717 * }
2718 * }
2719 * </programlisting>
2720 * </example>
2721 *
2722 * Since: 2.24
2723 **/
2724 GVariant *
2725 g_variant_iter_next_value (GVariantIter *iter)
2726 {
2727 g_return_val_if_fail (is_valid_iter (iter), FALSE);
2728
2729 if G_UNLIKELY (GVSI(iter)->i >= GVSI(iter)->n)
2730 {
2731 g_critical ("g_variant_iter_next_value: must not be called again "
2732 "after NULL has already been returned.");
2733 return NULL;
2734 }
2735
2736 GVSI(iter)->i++;
2737
2738 if (GVSI(iter)->i < GVSI(iter)->n)
2739 return g_variant_get_child_value (GVSI(iter)->value, GVSI(iter)->i);
2740
2741 return NULL;
2742 }
2743
2744 /* GVariantBuilder {{{1 */
2745 /**
2746 * GVariantBuilder:
2747 *
2748 * A utility type for constructing container-type #GVariant instances.
2749 *
2750 * This is an opaque structure and may only be accessed using the
2751 * following functions.
2752 *
2753 * #GVariantBuilder is not threadsafe in any way. Do not attempt to
2754 * access it from more than one thread.
2755 **/
2756
2757 struct stack_builder
2758 {
2759 GVariantBuilder *parent;
2760 GVariantType *type;
2761
2762 /* type constraint explicitly specified by 'type'.
2763 * for tuple types, this moves along as we add more items.
2764 */
2765 const GVariantType *expected_type;
2766
2767 /* type constraint implied by previous array item.
2768 */
2769 const GVariantType *prev_item_type;
2770
2771 /* constraints on the number of children. max = -1 for unlimited. */
2772 gsize min_items;
2773 gsize max_items;
2774
2775 /* dynamically-growing pointer array */
2776 GVariant **children;
2777 gsize allocated_children;
2778 gsize offset;
2779
2780 /* set to '1' if all items in the container will have the same type
2781 * (ie: maybe, array, variant) '0' if not (ie: tuple, dict entry)
2782 */
2783 guint uniform_item_types : 1;
2784
2785 /* set to '1' initially and changed to '0' if an untrusted value is
2786 * added
2787 */
2788 guint trusted : 1;
2789
2790 gsize magic;
2791 };
2792
2793 G_STATIC_ASSERT (sizeof (struct stack_builder) <= sizeof (GVariantBuilder));
2794
2795 struct heap_builder
2796 {
2797 GVariantBuilder builder;
2798 gsize magic;
2799
2800 gint ref_count;
2801 };
2802
2803 #define GVSB(b) ((struct stack_builder *) (b))
2804 #define GVHB(b) ((struct heap_builder *) (b))
2805 #define GVSB_MAGIC ((gsize) 1033660112u)
2806 #define GVHB_MAGIC ((gsize) 3087242682u)
2807 #define is_valid_builder(b) (b != NULL && \
2808 GVSB(b)->magic == GVSB_MAGIC)
2809 #define is_valid_heap_builder(b) (GVHB(b)->magic == GVHB_MAGIC)
2810
2811 /**
2812 * g_variant_builder_new:
2813 * @type: a container type
2814 * @returns: (transfer full): a #GVariantBuilder
2815 *
2816 * Allocates and initialises a new #GVariantBuilder.
2817 *
2818 * You should call g_variant_builder_unref() on the return value when it
2819 * is no longer needed. The memory will not be automatically freed by
2820 * any other call.
2821 *
2822 * In most cases it is easier to place a #GVariantBuilder directly on
2823 * the stack of the calling function and initialise it with
2824 * g_variant_builder_init().
2825 *
2826 * Since: 2.24
2827 **/
2828 GVariantBuilder *
2829 g_variant_builder_new (const GVariantType *type)
2830 {
2831 GVariantBuilder *builder;
2832
2833 builder = (GVariantBuilder *) g_slice_new (struct heap_builder);
2834 #ifdef GSTREAMER_LITE
2835 if (builder == NULL) {
2836 return NULL;
2837 }
2838 #endif // GSTREAMER_LITE
2839 g_variant_builder_init (builder, type);
2840 GVHB(builder)->magic = GVHB_MAGIC;
2841 GVHB(builder)->ref_count = 1;
2842
2843 return builder;
2844 }
2845
2846 /**
2847 * g_variant_builder_unref:
2848 * @builder: (transfer full): a #GVariantBuilder allocated by g_variant_builder_new()
2849 *
2850 * Decreases the reference count on @builder.
2851 *
2852 * In the event that there are no more references, releases all memory
2853 * associated with the #GVariantBuilder.
2854 *
2855 * Don't call this on stack-allocated #GVariantBuilder instances or bad
2856 * things will happen.
2857 *
2858 * Since: 2.24
2859 **/
2860 void
2861 g_variant_builder_unref (GVariantBuilder *builder)
2862 {
2863 g_return_if_fail (is_valid_heap_builder (builder));
2864
2865 if (--GVHB(builder)->ref_count)
2866 return;
2867
2868 g_variant_builder_clear (builder);
2869 GVHB(builder)->magic = 0;
2870
2871 g_slice_free (struct heap_builder, GVHB(builder));
2872 }
2873
2874 /**
2875 * g_variant_builder_ref:
2876 * @builder: a #GVariantBuilder allocated by g_variant_builder_new()
2877 * @returns: (transfer full): a new reference to @builder
2878 *
2879 * Increases the reference count on @builder.
2880 *
2881 * Don't call this on stack-allocated #GVariantBuilder instances or bad
2882 * things will happen.
2883 *
2884 * Since: 2.24
2885 **/
2886 GVariantBuilder *
2887 g_variant_builder_ref (GVariantBuilder *builder)
2888 {
2889 g_return_val_if_fail (is_valid_heap_builder (builder), NULL);
2890
2891 GVHB(builder)->ref_count++;
2892
2893 return builder;
2894 }
2895
2896 /**
2897 * g_variant_builder_clear: (skip)
2898 * @builder: a #GVariantBuilder
2899 *
2900 * Releases all memory associated with a #GVariantBuilder without
2901 * freeing the #GVariantBuilder structure itself.
2902 *
2903 * It typically only makes sense to do this on a stack-allocated
2904 * #GVariantBuilder if you want to abort building the value part-way
2905 * through. This function need not be called if you call
2906 * g_variant_builder_end() and it also doesn't need to be called on
2907 * builders allocated with g_variant_builder_new (see
2908 * g_variant_builder_unref() for that).
2909 *
2910 * This function leaves the #GVariantBuilder structure set to all-zeros.
2911 * It is valid to call this function on either an initialised
2912 * #GVariantBuilder or one that is set to all-zeros but it is not valid
2913 * to call this function on uninitialised memory.
2914 *
2915 * Since: 2.24
2916 **/
2917 void
2918 g_variant_builder_clear (GVariantBuilder *builder)
2919 {
2920 gsize i;
2921
2922 if (GVSB(builder)->magic == 0)
2923 /* all-zeros case */
2924 return;
2925
2926 g_return_if_fail (is_valid_builder (builder));
2927
2928 g_variant_type_free (GVSB(builder)->type);
2929
2930 for (i = 0; i < GVSB(builder)->offset; i++)
2931 g_variant_unref (GVSB(builder)->children[i]);
2932
2933 g_free (GVSB(builder)->children);
2934
2935 if (GVSB(builder)->parent)
2936 {
2937 g_variant_builder_clear (GVSB(builder)->parent);
2938 g_slice_free (GVariantBuilder, GVSB(builder)->parent);
2939 }
2940
2941 memset (builder, 0, sizeof (GVariantBuilder));
2942 }
2943
2944 /**
2945 * g_variant_builder_init: (skip)
2946 * @builder: a #GVariantBuilder
2947 * @type: a container type
2948 *
2949 * Initialises a #GVariantBuilder structure.
2950 *
2951 * @type must be non-%NULL. It specifies the type of container to
2952 * construct. It can be an indefinite type such as
2953 * %G_VARIANT_TYPE_ARRAY or a definite type such as "as" or "(ii)".
2954 * Maybe, array, tuple, dictionary entry and variant-typed values may be
2955 * constructed.
2956 *
2957 * After the builder is initialised, values are added using
2958 * g_variant_builder_add_value() or g_variant_builder_add().
2959 *
2960 * After all the child values are added, g_variant_builder_end() frees
2961 * the memory associated with the builder and returns the #GVariant that
2962 * was created.
2963 *
2964 * This function completely ignores the previous contents of @builder.
2965 * On one hand this means that it is valid to pass in completely
2966 * uninitialised memory. On the other hand, this means that if you are
2967 * initialising over top of an existing #GVariantBuilder you need to
2968 * first call g_variant_builder_clear() in order to avoid leaking
2969 * memory.
2970 *
2971 * You must not call g_variant_builder_ref() or
2972 * g_variant_builder_unref() on a #GVariantBuilder that was initialised
2973 * with this function. If you ever pass a reference to a
2974 * #GVariantBuilder outside of the control of your own code then you
2975 * should assume that the person receiving that reference may try to use
2976 * reference counting; you should use g_variant_builder_new() instead of
2977 * this function.
2978 *
2979 * Since: 2.24
2980 **/
2981 void
2982 g_variant_builder_init (GVariantBuilder *builder,
2983 const GVariantType *type)
2984 {
2985 g_return_if_fail (type != NULL);
2986 g_return_if_fail (g_variant_type_is_container (type));
2987
2988 memset (builder, 0, sizeof (GVariantBuilder));
2989
2990 GVSB(builder)->type = g_variant_type_copy (type);
2991 GVSB(builder)->magic = GVSB_MAGIC;
2992 GVSB(builder)->trusted = TRUE;
2993
2994 switch (*(const gchar *) type)
2995 {
2996 case G_VARIANT_CLASS_VARIANT:
2997 GVSB(builder)->uniform_item_types = TRUE;
2998 GVSB(builder)->allocated_children = 1;
2999 GVSB(builder)->expected_type = NULL;
3000 GVSB(builder)->min_items = 1;
3001 GVSB(builder)->max_items = 1;
3002 break;
3003
3004 case G_VARIANT_CLASS_ARRAY:
3005 GVSB(builder)->uniform_item_types = TRUE;
3006 GVSB(builder)->allocated_children = 8;
3007 GVSB(builder)->expected_type =
3008 g_variant_type_element (GVSB(builder)->type);
3009 GVSB(builder)->min_items = 0;
3010 GVSB(builder)->max_items = -1;
3011 break;
3012
3013 case G_VARIANT_CLASS_MAYBE:
3014 GVSB(builder)->uniform_item_types = TRUE;
3015 GVSB(builder)->allocated_children = 1;
3016 GVSB(builder)->expected_type =
3017 g_variant_type_element (GVSB(builder)->type);
3018 GVSB(builder)->min_items = 0;
3019 GVSB(builder)->max_items = 1;
3020 break;
3021
3022 case G_VARIANT_CLASS_DICT_ENTRY:
3023 GVSB(builder)->uniform_item_types = FALSE;
3024 GVSB(builder)->allocated_children = 2;
3025 GVSB(builder)->expected_type =
3026 g_variant_type_key (GVSB(builder)->type);
3027 GVSB(builder)->min_items = 2;
3028 GVSB(builder)->max_items = 2;
3029 break;
3030
3031 case 'r': /* G_VARIANT_TYPE_TUPLE was given */
3032 GVSB(builder)->uniform_item_types = FALSE;
3033 GVSB(builder)->allocated_children = 8;
3034 GVSB(builder)->expected_type = NULL;
3035 GVSB(builder)->min_items = 0;
3036 GVSB(builder)->max_items = -1;
3037 break;
3038
3039 case G_VARIANT_CLASS_TUPLE: /* a definite tuple type was given */
3040 GVSB(builder)->allocated_children = g_variant_type_n_items (type);
3041 GVSB(builder)->expected_type =
3042 g_variant_type_first (GVSB(builder)->type);
3043 GVSB(builder)->min_items = GVSB(builder)->allocated_children;
3044 GVSB(builder)->max_items = GVSB(builder)->allocated_children;
3045 GVSB(builder)->uniform_item_types = FALSE;
3046 break;
3047
3048 default:
3049 g_assert_not_reached ();
3050 }
3051
3052 GVSB(builder)->children = g_new (GVariant *,
3053 GVSB(builder)->allocated_children);
3054 }
3055
3056 static void
3057 g_variant_builder_make_room (struct stack_builder *builder)
3058 {
3059 if (builder->offset == builder->allocated_children)
3060 {
3061 builder->allocated_children *= 2;
3062 builder->children = g_renew (GVariant *, builder->children,
3063 builder->allocated_children);
3064 }
3065 }
3066
3067 /**
3068 * g_variant_builder_add_value:
3069 * @builder: a #GVariantBuilder
3070 * @value: a #GVariant
3071 *
3072 * Adds @value to @builder.
3073 *
3074 * It is an error to call this function in any way that would create an
3075 * inconsistent value to be constructed. Some examples of this are
3076 * putting different types of items into an array, putting the wrong
3077 * types or number of items in a tuple, putting more than one value into
3078 * a variant, etc.
3079 *
3080 * If @value is a floating reference (see g_variant_ref_sink()),
3081 * the @builder instance takes ownership of @value.
3082 *
3083 * Since: 2.24
3084 **/
3085 void
3086 g_variant_builder_add_value (GVariantBuilder *builder,
3087 GVariant *value)
3088 {
3089 g_return_if_fail (is_valid_builder (builder));
3090 g_return_if_fail (GVSB(builder)->offset < GVSB(builder)->max_items);
3091 g_return_if_fail (!GVSB(builder)->expected_type ||
3092 g_variant_is_of_type (value,
3093 GVSB(builder)->expected_type));
3094 g_return_if_fail (!GVSB(builder)->prev_item_type ||
3095 g_variant_is_of_type (value,
3096 GVSB(builder)->prev_item_type));
3097
3098 GVSB(builder)->trusted &= g_variant_is_trusted (value);
3099
3100 if (!GVSB(builder)->uniform_item_types)
3101 {
3102 /* advance our expected type pointers */
3103 if (GVSB(builder)->expected_type)
3104 GVSB(builder)->expected_type =
3105 g_variant_type_next (GVSB(builder)->expected_type);
3106
3107 if (GVSB(builder)->prev_item_type)
3108 GVSB(builder)->prev_item_type =
3109 g_variant_type_next (GVSB(builder)->prev_item_type);
3110 }
3111 else
3112 GVSB(builder)->prev_item_type = g_variant_get_type (value);
3113
3114 g_variant_builder_make_room (GVSB(builder));
3115
3116 GVSB(builder)->children[GVSB(builder)->offset++] =
3117 g_variant_ref_sink (value);
3118 }
3119
3120 /**
3121 * g_variant_builder_open:
3122 * @builder: a #GVariantBuilder
3123 * @type: a #GVariantType
3124 *
3125 * Opens a subcontainer inside the given @builder. When done adding
3126 * items to the subcontainer, g_variant_builder_close() must be called.
3127 *
3128 * It is an error to call this function in any way that would cause an
3129 * inconsistent value to be constructed (ie: adding too many values or
3130 * a value of an incorrect type).
3131 *
3132 * Since: 2.24
3133 **/
3134 void
3135 g_variant_builder_open (GVariantBuilder *builder,
3136 const GVariantType *type)
3137 {
3138 GVariantBuilder *parent;
3139
3140 g_return_if_fail (is_valid_builder (builder));
3141 g_return_if_fail (GVSB(builder)->offset < GVSB(builder)->max_items);
3142 g_return_if_fail (!GVSB(builder)->expected_type ||
3143 g_variant_type_is_subtype_of (type,
3144 GVSB(builder)->expected_type));
3145 g_return_if_fail (!GVSB(builder)->prev_item_type ||
3146 g_variant_type_is_subtype_of (GVSB(builder)->prev_item_type,
3147 type));
3148
3149 parent = g_slice_dup (GVariantBuilder, builder);
3150 g_variant_builder_init (builder, type);
3151 GVSB(builder)->parent = parent;
3152
3153 /* push the prev_item_type down into the subcontainer */
3154 if (GVSB(parent)->prev_item_type)
3155 {
3156 if (!GVSB(builder)->uniform_item_types)
3157 /* tuples and dict entries */
3158 GVSB(builder)->prev_item_type =
3159 g_variant_type_first (GVSB(parent)->prev_item_type);
3160
3161 else if (!g_variant_type_is_variant (GVSB(builder)->type))
3162 /* maybes and arrays */
3163 GVSB(builder)->prev_item_type =
3164 g_variant_type_element (GVSB(parent)->prev_item_type);
3165 }
3166 }
3167
3168 /**
3169 * g_variant_builder_close:
3170 * @builder: a #GVariantBuilder
3171 *
3172 * Closes the subcontainer inside the given @builder that was opened by
3173 * the most recent call to g_variant_builder_open().
3174 *
3175 * It is an error to call this function in any way that would create an
3176 * inconsistent value to be constructed (ie: too few values added to the
3177 * subcontainer).
3178 *
3179 * Since: 2.24
3180 **/
3181 void
3182 g_variant_builder_close (GVariantBuilder *builder)
3183 {
3184 GVariantBuilder *parent;
3185
3186 g_return_if_fail (is_valid_builder (builder));
3187 g_return_if_fail (GVSB(builder)->parent != NULL);
3188
3189 parent = GVSB(builder)->parent;
3190 GVSB(builder)->parent = NULL;
3191
3192 g_variant_builder_add_value (parent, g_variant_builder_end (builder));
3193 *builder = *parent;
3194
3195 g_slice_free (GVariantBuilder, parent);
3196 }
3197
3198 /*< private >
3199 * g_variant_make_maybe_type:
3200 * @element: a #GVariant
3201 *
3202 * Return the type of a maybe containing @element.
3203 */
3204 static GVariantType *
3205 g_variant_make_maybe_type (GVariant *element)
3206 {
3207 return g_variant_type_new_maybe (g_variant_get_type (element));
3208 }
3209
3210 /*< private >
3211 * g_variant_make_array_type:
3212 * @element: a #GVariant
3213 *
3214 * Return the type of an array containing @element.
3215 */
3216 static GVariantType *
3217 g_variant_make_array_type (GVariant *element)
3218 {
3219 return g_variant_type_new_array (g_variant_get_type (element));
3220 }
3221
3222 /**
3223 * g_variant_builder_end:
3224 * @builder: a #GVariantBuilder
3225 * @returns: (transfer none): a new, floating, #GVariant
3226 *
3227 * Ends the builder process and returns the constructed value.
3228 *
3229 * It is not permissible to use @builder in any way after this call
3230 * except for reference counting operations (in the case of a
3231 * heap-allocated #GVariantBuilder) or by reinitialising it with
3232 * g_variant_builder_init() (in the case of stack-allocated).
3233 *
3234 * It is an error to call this function in any way that would create an
3235 * inconsistent value to be constructed (ie: insufficient number of
3236 * items added to a container with a specific number of children
3237 * required). It is also an error to call this function if the builder
3238 * was created with an indefinite array or maybe type and no children
3239 * have been added; in this case it is impossible to infer the type of
3240 * the empty array.
3241 *
3242 * Since: 2.24
3243 **/
3244 GVariant *
3245 g_variant_builder_end (GVariantBuilder *builder)
3246 {
3247 GVariantType *my_type;
3248 GVariant *value;
3249
3250 g_return_val_if_fail (is_valid_builder (builder), NULL);
3251 g_return_val_if_fail (GVSB(builder)->offset >= GVSB(builder)->min_items,
3252 NULL);
3253 g_return_val_if_fail (!GVSB(builder)->uniform_item_types ||
3254 GVSB(builder)->prev_item_type != NULL ||
3255 g_variant_type_is_definite (GVSB(builder)->type),
3256 NULL);
3257
3258 if (g_variant_type_is_definite (GVSB(builder)->type))
3259 my_type = g_variant_type_copy (GVSB(builder)->type);
3260
3261 else if (g_variant_type_is_maybe (GVSB(builder)->type))
3262 my_type = g_variant_make_maybe_type (GVSB(builder)->children[0]);
3263
3264 else if (g_variant_type_is_array (GVSB(builder)->type))
3265 my_type = g_variant_make_array_type (GVSB(builder)->children[0]);
3266
3267 else if (g_variant_type_is_tuple (GVSB(builder)->type))
3268 my_type = g_variant_make_tuple_type (GVSB(builder)->children,
3269 GVSB(builder)->offset);
3270
3271 else if (g_variant_type_is_dict_entry (GVSB(builder)->type))
3272 my_type = g_variant_make_dict_entry_type (GVSB(builder)->children[0],
3273 GVSB(builder)->children[1]);
3274 else
3275 g_assert_not_reached ();
3276
3277 value = g_variant_new_from_children (my_type,
3278 g_renew (GVariant *,
3279 GVSB(builder)->children,
3280 GVSB(builder)->offset),
3281 GVSB(builder)->offset,
3282 GVSB(builder)->trusted);
3283 GVSB(builder)->children = NULL;
3284 GVSB(builder)->offset = 0;
3285
3286 g_variant_builder_clear (builder);
3287 g_variant_type_free (my_type);
3288
3289 return value;
3290 }
3291
3292 /* Format strings {{{1 */
3293 /*< private >
3294 * g_variant_format_string_scan:
3295 * @string: a string that may be prefixed with a format string
3296 * @limit: (allow-none) (default NULL): a pointer to the end of @string,
3297 * or %NULL
3298 * @endptr: (allow-none) (default NULL): location to store the end pointer,
3299 * or %NULL
3300 * @returns: %TRUE if there was a valid format string
3301 *
3302 * Checks the string pointed to by @string for starting with a properly
3303 * formed #GVariant varargs format string. If no valid format string is
3304 * found then %FALSE is returned.
3305 *
3306 * If @string does start with a valid format string then %TRUE is
3307 * returned. If @endptr is non-%NULL then it is updated to point to the
3308 * first character after the format string.
3309 *
3310 * If @limit is non-%NULL then @limit (and any charater after it) will
3311 * not be accessed and the effect is otherwise equivalent to if the
3312 * character at @limit were nul.
3313 *
3314 * See the section on <link linkend='gvariant-format-strings'>GVariant
3315 * Format Strings</link>.
3316 *
3317 * Since: 2.24
3318 */
3319 gboolean
3320 g_variant_format_string_scan (const gchar *string,
3321 const gchar *limit,
3322 const gchar **endptr)
3323 {
3324 #define next_char() (string == limit ? '\0' : *string++)
3325 #define peek_char() (string == limit ? '\0' : *string)
3326 char c;
3327
3328 switch (next_char())
3329 {
3330 case 'b': case 'y': case 'n': case 'q': case 'i': case 'u':
3331 case 'x': case 't': case 'h': case 'd': case 's': case 'o':
3332 case 'g': case 'v': case '*': case '?': case 'r':
3333 break;
3334
3335 case 'm':
3336 return g_variant_format_string_scan (string, limit, endptr);
3337
3338 case 'a':
3339 case '@':
3340 return g_variant_type_string_scan (string, limit, endptr);
3341
3342 case '(':
3343 while (peek_char() != ')')
3344 if (!g_variant_format_string_scan (string, limit, &string))
3345 return FALSE;
3346
3347 next_char(); /* consume ')' */
3348 break;
3349
3350 case '{':
3351 c = next_char();
3352
3353 if (c == '&')
3354 {
3355 c = next_char ();
3356
3357 if (c != 's' && c != 'o' && c != 'g')
3358 return FALSE;
3359 }
3360 else
3361 {
3362 if (c == '@')
3363 c = next_char ();
3364
3365 /* ISO/IEC 9899:1999 (C99) §7.21.5.2:
3366 * The terminating null character is considered to be
3367 * part of the string.
3368 */
3369 if (c != '\0' && strchr ("bynqiuxthdsog?", c) == NULL)
3370 return FALSE;
3371 }
3372
3373 if (!g_variant_format_string_scan (string, limit, &string))
3374 return FALSE;
3375
3376 if (next_char() != '}')
3377 return FALSE;
3378
3379 break;
3380
3381 case '^':
3382 if ((c = next_char()) == 'a')
3383 {
3384 if ((c = next_char()) == '&')
3385 {
3386 if ((c = next_char()) == 'a')
3387 {
3388 if ((c = next_char()) == 'y')
3389 break; /* '^a&ay' */
3390 }
3391
3392 else if (c == 's')
3393 break; /* '^a&s' */
3394 }
3395
3396 else if (c == 'a')
3397 {
3398 if ((c = next_char()) == 'y')
3399 break; /* '^aay' */
3400 }
3401
3402 else if (c == 's')
3403 break; /* '^as' */
3404
3405 else if (c == 'y')
3406 break; /* '^ay' */
3407 }
3408 else if (c == '&')
3409 {
3410 if ((c = next_char()) == 'a')
3411 {
3412 if ((c = next_char()) == 'y')
3413 break; /* '^&ay' */
3414 }
3415 }
3416
3417 return FALSE;
3418
3419 case '&':
3420 c = next_char();
3421
3422 if (c != 's' && c != 'o' && c != 'g')
3423 return FALSE;
3424
3425 break;
3426
3427 default:
3428 return FALSE;
3429 }
3430
3431 if (endptr != NULL)
3432 *endptr = string;
3433
3434 #undef next_char
3435 #undef peek_char
3436
3437 return TRUE;
3438 }
3439
3440 /*< private >
3441 * g_variant_format_string_scan_type:
3442 * @string: a string that may be prefixed with a format string
3443 * @limit: (allow-none) (default NULL): a pointer to the end of @string,
3444 * or %NULL
3445 * @endptr: (allow-none) (default NULL): location to store the end pointer,
3446 * or %NULL
3447 * @returns: (allow-none): a #GVariantType if there was a valid format string
3448 *
3449 * If @string starts with a valid format string then this function will
3450 * return the type that the format string corresponds to. Otherwise
3451 * this function returns %NULL.
3452 *
3453 * Use g_variant_type_free() to free the return value when you no longer
3454 * need it.
3455 *
3456 * This function is otherwise exactly like
3457 * g_variant_format_string_scan().
3458 *
3459 * Since: 2.24
3460 */
3461 GVariantType *
3462 g_variant_format_string_scan_type (const gchar *string,
3463 const gchar *limit,
3464 const gchar **endptr)
3465 {
3466 const gchar *my_end;
3467 gchar *dest;
3468 gchar *new;
3469
3470 if (endptr == NULL)
3471 endptr = &my_end;
3472
3473 if (!g_variant_format_string_scan (string, limit, endptr))
3474 return NULL;
3475
3476 dest = new = g_malloc (*endptr - string + 1);
3477 while (string != *endptr)
3478 {
3479 if (*string != '@' && *string != '&' && *string != '^')
3480 *dest++ = *string;
3481 string++;
3482 }
3483 *dest = '\0';
3484
3485 return (GVariantType *) G_VARIANT_TYPE (new);
3486 }
3487
3488 static gboolean
3489 valid_format_string (const gchar *format_string,
3490 gboolean single,
3491 GVariant *value)
3492 {
3493 const gchar *endptr;
3494 GVariantType *type;
3495
3496 type = g_variant_format_string_scan_type (format_string, NULL, &endptr);
3497
3498 if G_UNLIKELY (type == NULL || (single && *endptr != '\0'))
3499 {
3500 if (single)
3501 g_critical ("`%s' is not a valid GVariant format string",
3502 format_string);
3503 else
3504 g_critical ("`%s' does not have a valid GVariant format "
3505 "string as a prefix", format_string);
3506
3507 if (type != NULL)
3508 g_variant_type_free (type);
3509
3510 return FALSE;
3511 }
3512
3513 if G_UNLIKELY (value && !g_variant_is_of_type (value, type))
3514 {
3515 gchar *fragment;
3516 gchar *typestr;
3517
3518 fragment = g_strndup (format_string, endptr - format_string);
3519 typestr = g_variant_type_dup_string (type);
3520
3521 g_critical ("the GVariant format string `%s' has a type of "
3522 "`%s' but the given value has a type of `%s'",
3523 fragment, typestr, g_variant_get_type_string (value));
3524
3525 g_variant_type_free (type);
3526
3527 return FALSE;
3528 }
3529
3530 g_variant_type_free (type);
3531
3532 return TRUE;
3533 }
3534
3535 /* Variable Arguments {{{1 */
3536 /* We consider 2 main classes of format strings:
3537 *
3538 * - recursive format strings
3539 * these are ones that result in recursion and the collection of
3540 * possibly more than one argument. Maybe types, tuples,
3541 * dictionary entries.
3542 *
3543 * - leaf format string
3544 * these result in the collection of a single argument.
3545 *
3546 * Leaf format strings are further subdivided into two categories:
3547 *
3548 * - single non-null pointer ("nnp")
3549 * these either collect or return a single non-null pointer.
3550 *
3551 * - other
3552 * these collect or return something else (bool, number, etc).
3553 *
3554 * Based on the above, the varargs handling code is split into 4 main parts:
3555 *
3556 * - nnp handling code
3557 * - leaf handling code (which may invoke nnp code)
3558 * - generic handling code (may be recursive, may invoke leaf code)
3559 * - user-facing API (which invokes the generic code)
3560 *
3561 * Each section implements some of the following functions:
3562 *
3563 * - skip:
3564 * collect the arguments for the format string as if
3565 * g_variant_new() had been called, but do nothing with them. used
3566 * for skipping over arguments when constructing a Nothing maybe
3567 * type.
3568 *
3569 * - new:
3570 * create a GVariant *
3571 *
3572 * - get:
3573 * unpack a GVariant *
3574 *
3575 * - free (nnp only):
3576 * free a previously allocated item
3577 */
3578
3579 static gboolean
3580 g_variant_format_string_is_leaf (const gchar *str)
3581 {
3582 return str[0] != 'm' && str[0] != '(' && str[0] != '{';
3583 }
3584
3585 static gboolean
3586 g_variant_format_string_is_nnp (const gchar *str)
3587 {
3588 return str[0] == 'a' || str[0] == 's' || str[0] == 'o' || str[0] == 'g' ||
3589 str[0] == '^' || str[0] == '@' || str[0] == '*' || str[0] == '?' ||
3590 str[0] == 'r' || str[0] == 'v' || str[0] == '&';
3591 }
3592
3593 /* Single non-null pointer ("nnp") {{{2 */
3594 static void
3595 g_variant_valist_free_nnp (const gchar *str,
3596 gpointer ptr)
3597 {
3598 switch (*str)
3599 {
3600 case 'a':
3601 g_variant_iter_free (ptr);
3602 break;
3603
3604 case '^':
3605 if (str[2] != '&') /* '^as' */
3606 g_strfreev (ptr);
3607 else /* '^a&s' */
3608 g_free (ptr);
3609 break;
3610
3611 case 's':
3612 case 'o':
3613 case 'g':
3614 g_free (ptr);
3615 break;
3616
3617 case '@':
3618 case '*':
3619 case '?':
3620 case 'v':
3621 g_variant_unref (ptr);
3622 break;
3623
3624 case '&':
3625 break;
3626
3627 default:
3628 g_assert_not_reached ();
3629 }
3630 }
3631
3632 static gchar
3633 g_variant_scan_convenience (const gchar **str,
3634 gboolean *constant,
3635 guint *arrays)
3636 {
3637 *constant = FALSE;
3638 *arrays = 0;
3639
3640 for (;;)
3641 {
3642 char c = *(*str)++;
3643
3644 if (c == '&')
3645 *constant = TRUE;
3646
3647 else if (c == 'a')
3648 (*arrays)++;
3649
3650 else
3651 return c;
3652 }
3653 }
3654
3655 static GVariant *
3656 g_variant_valist_new_nnp (const gchar **str,
3657 gpointer ptr)
3658 {
3659 if (**str == '&')
3660 (*str)++;
3661
3662 switch (*(*str)++)
3663 {
3664 case 'a':
3665 if (ptr != NULL)
3666 {
3667 const GVariantType *type;
3668 GVariant *value;
3669
3670 value = g_variant_builder_end (ptr);
3671 type = g_variant_get_type (value);
3672
3673 if G_UNLIKELY (!g_variant_type_is_array (type))
3674 g_error ("g_variant_new: expected array GVariantBuilder but "
3675 "the built value has type `%s'",
3676 g_variant_get_type_string (value));
3677
3678 type = g_variant_type_element (type);
3679
3680 if G_UNLIKELY (!g_variant_type_is_subtype_of (type, (GVariantType *) *str))
3681 g_error ("g_variant_new: expected GVariantBuilder array element "
3682 "type `%s' but the built value has element type `%s'",
3683 g_variant_type_dup_string ((GVariantType *) *str),
3684 g_variant_get_type_string (value) + 1);
3685
3686 g_variant_type_string_scan (*str, NULL, str);
3687
3688 return value;
3689 }
3690 else
3691
3692 /* special case: NULL pointer for empty array */
3693 {
3694 const GVariantType *type = (GVariantType *) *str;
3695
3696 g_variant_type_string_scan (*str, NULL, str);
3697
3698 if G_UNLIKELY (!g_variant_type_is_definite (type))
3699 g_error ("g_variant_new: NULL pointer given with indefinite "
3700 "array type; unable to determine which type of empty "
3701 "array to construct.");
3702
3703 return g_variant_new_array (type, NULL, 0);
3704 }
3705
3706 case 's':
3707 {
3708 GVariant *value;
3709
3710 value = g_variant_new_string (ptr);
3711
3712 if (value == NULL)
3713 value = g_variant_new_string ("[Invalid UTF-8]");
3714
3715 return value;
3716 }
3717
3718 case 'o':
3719 return g_variant_new_object_path (ptr);
3720
3721 case 'g':
3722 return g_variant_new_signature (ptr);
3723
3724 case '^':
3725 {
3726 gboolean constant;
3727 guint arrays;
3728
3729 if (g_variant_scan_convenience (str, &constant, &arrays) == 's')
3730 return g_variant_new_strv (ptr, -1);
3731
3732 if (arrays > 1)
3733 return g_variant_new_bytestring_array (ptr, -1);
3734
3735 return g_variant_new_bytestring (ptr);
3736 }
3737
3738 case '@':
3739 if G_UNLIKELY (!g_variant_is_of_type (ptr, (GVariantType *) *str))
3740 g_error ("g_variant_new: expected GVariant of type `%s' but "
3741 "received value has type `%s'",
3742 g_variant_type_dup_string ((GVariantType *) *str),
3743 g_variant_get_type_string (ptr));
3744
3745 g_variant_type_string_scan (*str, NULL, str);
3746
3747 return ptr;
3748
3749 case '*':
3750 return ptr;
3751
3752 case '?':
3753 if G_UNLIKELY (!g_variant_type_is_basic (g_variant_get_type (ptr)))
3754 g_error ("g_variant_new: format string `?' expects basic-typed "
3755 "GVariant, but received value has type `%s'",
3756 g_variant_get_type_string (ptr));
3757
3758 return ptr;
3759
3760 case 'r':
3761 if G_UNLIKELY (!g_variant_type_is_tuple (g_variant_get_type (ptr)))
3762 g_error ("g_variant_new: format string `r` expects tuple-typed "
3763 "GVariant, but received value has type `%s'",
3764 g_variant_get_type_string (ptr));
3765
3766 return ptr;
3767
3768 case 'v':
3769 return g_variant_new_variant (ptr);
3770
3771 default:
3772 g_assert_not_reached ();
3773 }
3774 }
3775
3776 static gpointer
3777 g_variant_valist_get_nnp (const gchar **str,
3778 GVariant *value)
3779 {
3780 switch (*(*str)++)
3781 {
3782 case 'a':
3783 g_variant_type_string_scan (*str, NULL, str);
3784 return g_variant_iter_new (value);
3785
3786 case '&':
3787 (*str)++;
3788 return (gchar *) g_variant_get_string (value, NULL);
3789
3790 case 's':
3791 case 'o':
3792 case 'g':
3793 return g_variant_dup_string (value, NULL);
3794
3795 case '^':
3796 {
3797 gboolean constant;
3798 guint arrays;
3799
3800 if (g_variant_scan_convenience (str, &constant, &arrays) == 's')
3801 {
3802 if (constant)
3803 return g_variant_get_strv (value, NULL);
3804 else
3805 return g_variant_dup_strv (value, NULL);
3806 }
3807
3808 else if (arrays > 1)
3809 {
3810 if (constant)
3811 return g_variant_get_bytestring_array (value, NULL);
3812 else
3813 return g_variant_dup_bytestring_array (value, NULL);
3814 }
3815
3816 else
3817 {
3818 if (constant)
3819 return (gchar *) g_variant_get_bytestring (value);
3820 else
3821 return g_variant_dup_bytestring (value, NULL);
3822 }
3823 }
3824
3825 case '@':
3826 g_variant_type_string_scan (*str, NULL, str);
3827 /* fall through */
3828
3829 case '*':
3830 case '?':
3831 case 'r':
3832 return g_variant_ref (value);
3833
3834 case 'v':
3835 return g_variant_get_variant (value);
3836
3837 default:
3838 g_assert_not_reached ();
3839 }
3840 }
3841
3842 /* Leaves {{{2 */
3843 static void
3844 g_variant_valist_skip_leaf (const gchar **str,
3845 va_list *app)
3846 {
3847 if (g_variant_format_string_is_nnp (*str))
3848 {
3849 g_variant_format_string_scan (*str, NULL, str);
3850 va_arg (*app, gpointer);
3851 return;
3852 }
3853
3854 switch (*(*str)++)
3855 {
3856 case 'b':
3857 case 'y':
3858 case 'n':
3859 case 'q':
3860 case 'i':
3861 case 'u':
3862 case 'h':
3863 va_arg (*app, int);
3864 return;
3865
3866 case 'x':
3867 case 't':
3868 va_arg (*app, guint64);
3869 return;
3870
3871 case 'd':
3872 va_arg (*app, gdouble);
3873 return;
3874
3875 default:
3876 g_assert_not_reached ();
3877 }
3878 }
3879
3880 static GVariant *
3881 g_variant_valist_new_leaf (const gchar **str,
3882 va_list *app)
3883 {
3884 if (g_variant_format_string_is_nnp (*str))
3885 return g_variant_valist_new_nnp (str, va_arg (*app, gpointer));
3886
3887 switch (*(*str)++)
3888 {
3889 case 'b':
3890 return g_variant_new_boolean (va_arg (*app, gboolean));
3891
3892 case 'y':
3893 return g_variant_new_byte (va_arg (*app, guint));
3894
3895 case 'n':
3896 return g_variant_new_int16 (va_arg (*app, gint));
3897
3898 case 'q':
3899 return g_variant_new_uint16 (va_arg (*app, guint));
3900
3901 case 'i':
3902 return g_variant_new_int32 (va_arg (*app, gint));
3903
3904 case 'u':
3905 return g_variant_new_uint32 (va_arg (*app, guint));
3906
3907 case 'x':
3908 return g_variant_new_int64 (va_arg (*app, gint64));
3909
3910 case 't':
3911 return g_variant_new_uint64 (va_arg (*app, guint64));
3912
3913 case 'h':
3914 return g_variant_new_handle (va_arg (*app, gint));
3915
3916 case 'd':
3917 return g_variant_new_double (va_arg (*app, gdouble));
3918
3919 default:
3920 g_assert_not_reached ();
3921 }
3922 }
3923
3924 /* The code below assumes this */
3925 G_STATIC_ASSERT (sizeof (gboolean) == sizeof (guint32));
3926 G_STATIC_ASSERT (sizeof (gdouble) == sizeof (guint64));
3927
3928 static void
3929 g_variant_valist_get_leaf (const gchar **str,
3930 GVariant *value,
3931 gboolean free,
3932 va_list *app)
3933 {
3934 gpointer ptr = va_arg (*app, gpointer);
3935
3936 if (ptr == NULL)
3937 {
3938 g_variant_format_string_scan (*str, NULL, str);
3939 return;
3940 }
3941
3942 if (g_variant_format_string_is_nnp (*str))
3943 {
3944 gpointer *nnp = (gpointer *) ptr;
3945
3946 if (free && *nnp != NULL)
3947 g_variant_valist_free_nnp (*str, *nnp);
3948
3949 *nnp = NULL;
3950
3951 if (value != NULL)
3952 *nnp = g_variant_valist_get_nnp (str, value);
3953 else
3954 g_variant_format_string_scan (*str, NULL, str);
3955
3956 return;
3957 }
3958
3959 if (value != NULL)
3960 {
3961 switch (*(*str)++)
3962 {
3963 case 'b':
3964 *(gboolean *) ptr = g_variant_get_boolean (value);
3965 return;
3966
3967 case 'y':
3968 *(guchar *) ptr = g_variant_get_byte (value);
3969 return;
3970
3971 case 'n':
3972 *(gint16 *) ptr = g_variant_get_int16 (value);
3973 return;
3974
3975 case 'q':
3976 *(guint16 *) ptr = g_variant_get_uint16 (value);
3977 return;
3978
3979 case 'i':
3980 *(gint32 *) ptr = g_variant_get_int32 (value);
3981 return;
3982
3983 case 'u':
3984 *(guint32 *) ptr = g_variant_get_uint32 (value);
3985 return;
3986
3987 case 'x':
3988 *(gint64 *) ptr = g_variant_get_int64 (value);
3989 return;
3990
3991 case 't':
3992 *(guint64 *) ptr = g_variant_get_uint64 (value);
3993 return;
3994
3995 case 'h':
3996 *(gint32 *) ptr = g_variant_get_handle (value);
3997 return;
3998
3999 case 'd':
4000 *(gdouble *) ptr = g_variant_get_double (value);
4001 return;
4002 }
4003 }
4004 else
4005 {
4006 switch (*(*str)++)
4007 {
4008 case 'y':
4009 *(guchar *) ptr = 0;
4010 return;
4011
4012 case 'n':
4013 case 'q':
4014 *(guint16 *) ptr = 0;
4015 return;
4016
4017 case 'i':
4018 case 'u':
4019 case 'h':
4020 case 'b':
4021 *(guint32 *) ptr = 0;
4022 return;
4023
4024 case 'x':
4025 case 't':
4026 case 'd':
4027 *(guint64 *) ptr = 0;
4028 return;
4029 }
4030 }
4031
4032 g_assert_not_reached ();
4033 }
4034
4035 /* Generic (recursive) {{{2 */
4036 static void
4037 g_variant_valist_skip (const gchar **str,
4038 va_list *app)
4039 {
4040 if (g_variant_format_string_is_leaf (*str))
4041 g_variant_valist_skip_leaf (str, app);
4042
4043 else if (**str == 'm') /* maybe */
4044 {
4045 (*str)++;
4046
4047 if (!g_variant_format_string_is_nnp (*str))
4048 va_arg (*app, gboolean);
4049
4050 g_variant_valist_skip (str, app);
4051 }
4052 else /* tuple, dictionary entry */
4053 {
4054 g_assert (**str == '(' || **str == '{');
4055 (*str)++;
4056 while (**str != ')' && **str != '}')
4057 g_variant_valist_skip (str, app);
4058 (*str)++;
4059 }
4060 }
4061
4062 static GVariant *
4063 g_variant_valist_new (const gchar **str,
4064 va_list *app)
4065 {
4066 if (g_variant_format_string_is_leaf (*str))
4067 return g_variant_valist_new_leaf (str, app);
4068
4069 if (**str == 'm') /* maybe */
4070 {
4071 GVariantType *type = NULL;
4072 GVariant *value = NULL;
4073
4074 (*str)++;
4075
4076 if (g_variant_format_string_is_nnp (*str))
4077 {
4078 gpointer nnp = va_arg (*app, gpointer);
4079
4080 if (nnp != NULL)
4081 value = g_variant_valist_new_nnp (str, nnp);
4082 else
4083 type = g_variant_format_string_scan_type (*str, NULL, str);
4084 }
4085 else
4086 {
4087 gboolean just = va_arg (*app, gboolean);
4088
4089 if (just)
4090 value = g_variant_valist_new (str, app);
4091 else
4092 {
4093 type = g_variant_format_string_scan_type (*str, NULL, NULL);
4094 g_variant_valist_skip (str, app);
4095 }
4096 }
4097
4098 value = g_variant_new_maybe (type, value);
4099
4100 if (type != NULL)
4101 g_variant_type_free (type);
4102
4103 return value;
4104 }
4105 else /* tuple, dictionary entry */
4106 {
4107 GVariantBuilder b;
4108
4109 if (**str == '(')
4110 g_variant_builder_init (&b, G_VARIANT_TYPE_TUPLE);
4111 else
4112 {
4113 g_assert (**str == '{');
4114 g_variant_builder_init (&b, G_VARIANT_TYPE_DICT_ENTRY);
4115 }
4116
4117 (*str)++; /* '(' */
4118 while (**str != ')' && **str != '}')
4119 g_variant_builder_add_value (&b, g_variant_valist_new (str, app));
4120 (*str)++; /* ')' */
4121
4122 return g_variant_builder_end (&b);
4123 }
4124 }
4125
4126 static void
4127 g_variant_valist_get (const gchar **str,
4128 GVariant *value,
4129 gboolean free,
4130 va_list *app)
4131 {
4132 if (g_variant_format_string_is_leaf (*str))
4133 g_variant_valist_get_leaf (str, value, free, app);
4134
4135 else if (**str == 'm')
4136 {
4137 (*str)++;
4138
4139 if (value != NULL)
4140 value = g_variant_get_maybe (value);
4141
4142 if (!g_variant_format_string_is_nnp (*str))
4143 {
4144 gboolean *ptr = va_arg (*app, gboolean *);
4145
4146 if (ptr != NULL)
4147 *ptr = value != NULL;
4148 }
4149
4150 g_variant_valist_get (str, value, free, app);
4151
4152 if (value != NULL)
4153 g_variant_unref (value);
4154 }
4155
4156 else /* tuple, dictionary entry */
4157 {
4158 gint index = 0;
4159
4160 g_assert (**str == '(' || **str == '{');
4161
4162 (*str)++;
4163 while (**str != ')' && **str != '}')
4164 {
4165 if (value != NULL)
4166 {
4167 GVariant *child = g_variant_get_child_value (value, index++);
4168 g_variant_valist_get (str, child, free, app);
4169 g_variant_unref (child);
4170 }
4171 else
4172 g_variant_valist_get (str, NULL, free, app);
4173 }
4174 (*str)++;
4175 }
4176 }
4177
4178 /* User-facing API {{{2 */
4179 /**
4180 * g_variant_new: (skip)
4181 * @format_string: a #GVariant format string
4182 * @...: arguments, as per @format_string
4183 * @returns: a new floating #GVariant instance
4184 *
4185 * Creates a new #GVariant instance.
4186 *
4187 * Think of this function as an analogue to g_strdup_printf().
4188 *
4189 * The type of the created instance and the arguments that are
4190 * expected by this function are determined by @format_string. See the
4191 * section on <link linkend='gvariant-format-strings'>GVariant Format
4192 * Strings</link>. Please note that the syntax of the format string is
4193 * very likely to be extended in the future.
4194 *
4195 * The first character of the format string must not be '*' '?' '@' or
4196 * 'r'; in essence, a new #GVariant must always be constructed by this
4197 * function (and not merely passed through it unmodified).
4198 *
4199 * Since: 2.24
4200 **/
4201 GVariant *
4202 g_variant_new (const gchar *format_string,
4203 ...)
4204 {
4205 GVariant *value;
4206 va_list ap;
4207
4208 g_return_val_if_fail (valid_format_string (format_string, TRUE, NULL) &&
4209 format_string[0] != '?' && format_string[0] != '@' &&
4210 format_string[0] != '*' && format_string[0] != 'r',
4211 NULL);
4212
4213 va_start (ap, format_string);
4214 value = g_variant_new_va (format_string, NULL, &ap);
4215 va_end (ap);
4216
4217 return value;
4218 }
4219
4220 /**
4221 * g_variant_new_va: (skip)
4222 * @format_string: a string that is prefixed with a format string
4223 * @endptr: (allow-none) (default NULL): location to store the end pointer,
4224 * or %NULL
4225 * @app: a pointer to a #va_list
4226 * @returns: a new, usually floating, #GVariant
4227 *
4228 * This function is intended to be used by libraries based on
4229 * #GVariant that want to provide g_variant_new()-like functionality
4230 * to their users.
4231 *
4232 * The API is more general than g_variant_new() to allow a wider range
4233 * of possible uses.
4234 *
4235 * @format_string must still point to a valid format string, but it only
4236 * needs to be nul-terminated if @endptr is %NULL. If @endptr is
4237 * non-%NULL then it is updated to point to the first character past the
4238 * end of the format string.
4239 *
4240 * @app is a pointer to a #va_list. The arguments, according to
4241 * @format_string, are collected from this #va_list and the list is left
4242 * pointing to the argument following the last.
4243 *
4244 * These two generalisations allow mixing of multiple calls to
4245 * g_variant_new_va() and g_variant_get_va() within a single actual
4246 * varargs call by the user.
4247 *
4248 * The return value will be floating if it was a newly created GVariant
4249 * instance (for example, if the format string was "(ii)"). In the case
4250 * that the format_string was '*', '?', 'r', or a format starting with
4251 * '@' then the collected #GVariant pointer will be returned unmodified,
4252 * without adding any additional references.
4253 *
4254 * In order to behave correctly in all cases it is necessary for the
4255 * calling function to g_variant_ref_sink() the return result before
4256 * returning control to the user that originally provided the pointer.
4257 * At this point, the caller will have their own full reference to the
4258 * result. This can also be done by adding the result to a container,
4259 * or by passing it to another g_variant_new() call.
4260 *
4261 * Since: 2.24
4262 **/
4263 GVariant *
4264 g_variant_new_va (const gchar *format_string,
4265 const gchar **endptr,
4266 va_list *app)
4267 {
4268 GVariant *value;
4269
4270 g_return_val_if_fail (valid_format_string (format_string, !endptr, NULL),
4271 NULL);
4272 g_return_val_if_fail (app != NULL, NULL);
4273
4274 value = g_variant_valist_new (&format_string, app);
4275
4276 if (endptr != NULL)
4277 *endptr = format_string;
4278
4279 return value;
4280 }
4281
4282 /**
4283 * g_variant_get: (skip)
4284 * @value: a #GVariant instance
4285 * @format_string: a #GVariant format string
4286 * @...: arguments, as per @format_string
4287 *
4288 * Deconstructs a #GVariant instance.
4289 *
4290 * Think of this function as an analogue to scanf().
4291 *
4292 * The arguments that are expected by this function are entirely
4293 * determined by @format_string. @format_string also restricts the
4294 * permissible types of @value. It is an error to give a value with
4295 * an incompatible type. See the section on <link
4296 * linkend='gvariant-format-strings'>GVariant Format Strings</link>.
4297 * Please note that the syntax of the format string is very likely to be
4298 * extended in the future.
4299 *
4300 * Since: 2.24
4301 **/
4302 void
4303 g_variant_get (GVariant *value,
4304 const gchar *format_string,
4305 ...)
4306 {
4307 va_list ap;
4308
4309 g_return_if_fail (valid_format_string (format_string, TRUE, value));
4310
4311 /* if any direct-pointer-access formats are in use, flatten first */
4312 if (strchr (format_string, '&'))
4313 g_variant_get_data (value);
4314
4315 va_start (ap, format_string);
4316 g_variant_get_va (value, format_string, NULL, &ap);
4317 va_end (ap);
4318 }
4319
4320 /**
4321 * g_variant_get_va: (skip)
4322 * @value: a #GVariant
4323 * @format_string: a string that is prefixed with a format string
4324 * @endptr: (allow-none) (default NULL): location to store the end pointer,
4325 * or %NULL
4326 * @app: a pointer to a #va_list
4327 *
4328 * This function is intended to be used by libraries based on #GVariant
4329 * that want to provide g_variant_get()-like functionality to their
4330 * users.
4331 *
4332 * The API is more general than g_variant_get() to allow a wider range
4333 * of possible uses.
4334 *
4335 * @format_string must still point to a valid format string, but it only
4336 * need to be nul-terminated if @endptr is %NULL. If @endptr is
4337 * non-%NULL then it is updated to point to the first character past the
4338 * end of the format string.
4339 *
4340 * @app is a pointer to a #va_list. The arguments, according to
4341 * @format_string, are collected from this #va_list and the list is left
4342 * pointing to the argument following the last.
4343 *
4344 * These two generalisations allow mixing of multiple calls to
4345 * g_variant_new_va() and g_variant_get_va() within a single actual
4346 * varargs call by the user.
4347 *
4348 * Since: 2.24
4349 **/
4350 void
4351 g_variant_get_va (GVariant *value,
4352 const gchar *format_string,
4353 const gchar **endptr,
4354 va_list *app)
4355 {
4356 g_return_if_fail (valid_format_string (format_string, !endptr, value));
4357 g_return_if_fail (value != NULL);
4358 g_return_if_fail (app != NULL);
4359
4360 /* if any direct-pointer-access formats are in use, flatten first */
4361 if (strchr (format_string, '&'))
4362 g_variant_get_data (value);
4363
4364 g_variant_valist_get (&format_string, value, FALSE, app);
4365
4366 if (endptr != NULL)
4367 *endptr = format_string;
4368 }
4369
4370 /* Varargs-enabled Utility Functions {{{1 */
4371
4372 /**
4373 * g_variant_builder_add: (skp)
4374 * @builder: a #GVariantBuilder
4375 * @format_string: a #GVariant varargs format string
4376 * @...: arguments, as per @format_string
4377 *
4378 * Adds to a #GVariantBuilder.
4379 *
4380 * This call is a convenience wrapper that is exactly equivalent to
4381 * calling g_variant_new() followed by g_variant_builder_add_value().
4382 *
4383 * This function might be used as follows:
4384 *
4385 * <programlisting>
4386 * GVariant *
4387 * make_pointless_dictionary (void)
4388 * {
4389 * GVariantBuilder *builder;
4390 * int i;
4391 *
4392 * builder = g_variant_builder_new (G_VARIANT_TYPE_ARRAY);
4393 * for (i = 0; i < 16; i++)
4394 * {
4395 * gchar buf[3];
4396 *
4397 * sprintf (buf, "%d", i);
4398 * g_variant_builder_add (builder, "{is}", i, buf);
4399 * }
4400 *
4401 * return g_variant_builder_end (builder);
4402 * }
4403 * </programlisting>
4404 *
4405 * Since: 2.24
4406 **/
4407 void
4408 g_variant_builder_add (GVariantBuilder *builder,
4409 const gchar *format_string,
4410 ...)
4411 {
4412 GVariant *variant;
4413 va_list ap;
4414
4415 va_start (ap, format_string);
4416 variant = g_variant_new_va (format_string, NULL, &ap);
4417 va_end (ap);
4418
4419 g_variant_builder_add_value (builder, variant);
4420 }
4421
4422 /**
4423 * g_variant_get_child: (skip)
4424 * @value: a container #GVariant
4425 * @index_: the index of the child to deconstruct
4426 * @format_string: a #GVariant format string
4427 * @...: arguments, as per @format_string
4428 *
4429 * Reads a child item out of a container #GVariant instance and
4430 * deconstructs it according to @format_string. This call is
4431 * essentially a combination of g_variant_get_child_value() and
4432 * g_variant_get().
4433 *
4434 * Since: 2.24
4435 **/
4436 void
4437 g_variant_get_child (GVariant *value,
4438 gsize index_,
4439 const gchar *format_string,
4440 ...)
4441 {
4442 GVariant *child;
4443 va_list ap;
4444
4445 child = g_variant_get_child_value (value, index_);
4446 g_return_if_fail (valid_format_string (format_string, TRUE, child));
4447
4448 va_start (ap, format_string);
4449 g_variant_get_va (child, format_string, NULL, &ap);
4450 va_end (ap);
4451
4452 g_variant_unref (child);
4453 }
4454
4455 /**
4456 * g_variant_iter_next: (skip)
4457 * @iter: a #GVariantIter
4458 * @format_string: a GVariant format string
4459 * @...: the arguments to unpack the value into
4460 * @returns: %TRUE if a value was unpacked, or %FALSE if there as no
4461 * value
4462 *
4463 * Gets the next item in the container and unpacks it into the variable
4464 * argument list according to @format_string, returning %TRUE.
4465 *
4466 * If no more items remain then %FALSE is returned.
4467 *
4468 * All of the pointers given on the variable arguments list of this
4469 * function are assumed to point at uninitialised memory. It is the
4470 * responsibility of the caller to free all of the values returned by
4471 * the unpacking process.
4472 *
4473 * See the section on <link linkend='gvariant-format-strings'>GVariant
4474 * Format Strings</link>.
4475 *
4476 * <example>
4477 * <title>Memory management with g_variant_iter_next()</title>
4478 * <programlisting>
4479 * /<!-- -->* Iterates a dictionary of type 'a{sv}' *<!-- -->/
4480 * void
4481 * iterate_dictionary (GVariant *dictionary)
4482 * {
4483 * GVariantIter iter;
4484 * GVariant *value;
4485 * gchar *key;
4486 *
4487 * g_variant_iter_init (&iter, dictionary);
4488 * while (g_variant_iter_next (&iter, "{sv}", &key, &value))
4489 * {
4490 * g_print ("Item '%s' has type '%s'\n", key,
4491 * g_variant_get_type_string (value));
4492 *
4493 * /<!-- -->* must free data for ourselves *<!-- -->/
4494 * g_variant_unref (value);
4495 * g_free (key);
4496 * }
4497 * }
4498 * </programlisting>
4499 * </example>
4500 *
4501 * For a solution that is likely to be more convenient to C programmers
4502 * when dealing with loops, see g_variant_iter_loop().
4503 *
4504 * Since: 2.24
4505 **/
4506 gboolean
4507 g_variant_iter_next (GVariantIter *iter,
4508 const gchar *format_string,
4509 ...)
4510 {
4511 GVariant *value;
4512
4513 value = g_variant_iter_next_value (iter);
4514
4515 g_return_val_if_fail (valid_format_string (format_string, TRUE, value),
4516 FALSE);
4517
4518 if (value != NULL)
4519 {
4520 va_list ap;
4521
4522 va_start (ap, format_string);
4523 g_variant_valist_get (&format_string, value, FALSE, &ap);
4524 va_end (ap);
4525
4526 g_variant_unref (value);
4527 }
4528
4529 return value != NULL;
4530 }
4531
4532 /**
4533 * g_variant_iter_loop: (skip)
4534 * @iter: a #GVariantIter
4535 * @format_string: a GVariant format string
4536 * @...: the arguments to unpack the value into
4537 * @returns: %TRUE if a value was unpacked, or %FALSE if there as no
4538 * value
4539 *
4540 * Gets the next item in the container and unpacks it into the variable
4541 * argument list according to @format_string, returning %TRUE.
4542 *
4543 * If no more items remain then %FALSE is returned.
4544 *
4545 * On the first call to this function, the pointers appearing on the
4546 * variable argument list are assumed to point at uninitialised memory.
4547 * On the second and later calls, it is assumed that the same pointers
4548 * will be given and that they will point to the memory as set by the
4549 * previous call to this function. This allows the previous values to
4550 * be freed, as appropriate.
4551 *
4552 * This function is intended to be used with a while loop as
4553 * demonstrated in the following example. This function can only be
4554 * used when iterating over an array. It is only valid to call this
4555 * function with a string constant for the format string and the same
4556 * string constant must be used each time. Mixing calls to this
4557 * function and g_variant_iter_next() or g_variant_iter_next_value() on
4558 * the same iterator is not recommended.
4559 *
4560 * See the section on <link linkend='gvariant-format-strings'>GVariant
4561 * Format Strings</link>.
4562 *
4563 * <example>
4564 * <title>Memory management with g_variant_iter_loop()</title>
4565 * <programlisting>
4566 * /<!-- -->* Iterates a dictionary of type 'a{sv}' *<!-- -->/
4567 * void
4568 * iterate_dictionary (GVariant *dictionary)
4569 * {
4570 * GVariantIter iter;
4571 * GVariant *value;
4572 * gchar *key;
4573 *
4574 * g_variant_iter_init (&iter, dictionary);
4575 * while (g_variant_iter_loop (&iter, "{sv}", &key, &value))
4576 * {
4577 * g_print ("Item '%s' has type '%s'\n", key,
4578 * g_variant_get_type_string (value));
4579 *
4580 * /<!-- -->* no need to free 'key' and 'value' here *<!-- -->/
4581 * }
4582 * }
4583 * </programlisting>
4584 * </example>
4585 *
4586 * If you want a slightly less magical alternative that requires more
4587 * typing, see g_variant_iter_next().
4588 *
4589 * Since: 2.24
4590 **/
4591 gboolean
4592 g_variant_iter_loop (GVariantIter *iter,
4593 const gchar *format_string,
4594 ...)
4595 {
4596 gboolean first_time = GVSI(iter)->loop_format == NULL;
4597 GVariant *value;
4598 va_list ap;
4599
4600 g_return_val_if_fail (first_time ||
4601 format_string == GVSI(iter)->loop_format,
4602 FALSE);
4603
4604 if (first_time)
4605 {
4606 TYPE_CHECK (GVSI(iter)->value, G_VARIANT_TYPE_ARRAY, FALSE);
4607 GVSI(iter)->loop_format = format_string;
4608
4609 if (strchr (format_string, '&'))
4610 g_variant_get_data (GVSI(iter)->value);
4611 }
4612
4613 value = g_variant_iter_next_value (iter);
4614
4615 g_return_val_if_fail (!first_time ||
4616 valid_format_string (format_string, TRUE, value),
4617 FALSE);
4618
4619 va_start (ap, format_string);
4620 g_variant_valist_get (&format_string, value, !first_time, &ap);
4621 va_end (ap);
4622
4623 if (value != NULL)
4624 g_variant_unref (value);
4625
4626 return value != NULL;
4627 }
4628
4629 /* Serialised data {{{1 */
4630 static GVariant *
4631 g_variant_deep_copy (GVariant *value)
4632 {
4633 switch (g_variant_classify (value))
4634 {
4635 case G_VARIANT_CLASS_MAYBE:
4636 case G_VARIANT_CLASS_ARRAY:
4637 case G_VARIANT_CLASS_TUPLE:
4638 case G_VARIANT_CLASS_DICT_ENTRY:
4639 case G_VARIANT_CLASS_VARIANT:
4640 {
4641 GVariantBuilder builder;
4642 GVariantIter iter;
4643 GVariant *child;
4644
4645 g_variant_builder_init (&builder, g_variant_get_type (value));
4646 g_variant_iter_init (&iter, value);
4647
4648 while ((child = g_variant_iter_next_value (&iter)))
4649 {
4650 g_variant_builder_add_value (&builder, g_variant_deep_copy (child));
4651 g_variant_unref (child);
4652 }
4653
4654 return g_variant_builder_end (&builder);
4655 }
4656
4657 case G_VARIANT_CLASS_BOOLEAN:
4658 return g_variant_new_boolean (g_variant_get_boolean (value));
4659
4660 case G_VARIANT_CLASS_BYTE:
4661 return g_variant_new_byte (g_variant_get_byte (value));
4662
4663 case G_VARIANT_CLASS_INT16:
4664 return g_variant_new_int16 (g_variant_get_int16 (value));
4665
4666 case G_VARIANT_CLASS_UINT16:
4667 return g_variant_new_uint16 (g_variant_get_uint16 (value));
4668
4669 case G_VARIANT_CLASS_INT32:
4670 return g_variant_new_int32 (g_variant_get_int32 (value));
4671
4672 case G_VARIANT_CLASS_UINT32:
4673 return g_variant_new_uint32 (g_variant_get_uint32 (value));
4674
4675 case G_VARIANT_CLASS_INT64:
4676 return g_variant_new_int64 (g_variant_get_int64 (value));
4677
4678 case G_VARIANT_CLASS_UINT64:
4679 return g_variant_new_uint64 (g_variant_get_uint64 (value));
4680
4681 case G_VARIANT_CLASS_HANDLE:
4682 return g_variant_new_handle (g_variant_get_handle (value));
4683
4684 case G_VARIANT_CLASS_DOUBLE:
4685 return g_variant_new_double (g_variant_get_double (value));
4686
4687 case G_VARIANT_CLASS_STRING:
4688 return g_variant_new_string (g_variant_get_string (value, NULL));
4689
4690 case G_VARIANT_CLASS_OBJECT_PATH:
4691 return g_variant_new_object_path (g_variant_get_string (value, NULL));
4692
4693 case G_VARIANT_CLASS_SIGNATURE:
4694 return g_variant_new_signature (g_variant_get_string (value, NULL));
4695 }
4696
4697 g_assert_not_reached ();
4698 }
4699
4700 /**
4701 * g_variant_get_normal_form:
4702 * @value: a #GVariant
4703 * @returns: (transfer full): a trusted #GVariant
4704 *
4705 * Gets a #GVariant instance that has the same value as @value and is
4706 * trusted to be in normal form.
4707 *
4708 * If @value is already trusted to be in normal form then a new
4709 * reference to @value is returned.
4710 *
4711 * If @value is not already trusted, then it is scanned to check if it
4712 * is in normal form. If it is found to be in normal form then it is
4713 * marked as trusted and a new reference to it is returned.
4714 *
4715 * If @value is found not to be in normal form then a new trusted
4716 * #GVariant is created with the same value as @value.
4717 *
4718 * It makes sense to call this function if you've received #GVariant
4719 * data from untrusted sources and you want to ensure your serialised
4720 * output is definitely in normal form.
4721 *
4722 * Since: 2.24
4723 **/
4724 GVariant *
4725 g_variant_get_normal_form (GVariant *value)
4726 {
4727 GVariant *trusted;
4728
4729 if (g_variant_is_normal_form (value))
4730 return g_variant_ref (value);
4731
4732 trusted = g_variant_deep_copy (value);
4733 g_assert (g_variant_is_trusted (trusted));
4734
4735 return g_variant_ref_sink (trusted);
4736 }
4737
4738 /**
4739 * g_variant_byteswap:
4740 * @value: a #GVariant
4741 * @returns: (transfer full): the byteswapped form of @value
4742 *
4743 * Performs a byteswapping operation on the contents of @value. The
4744 * result is that all multi-byte numeric data contained in @value is
4745 * byteswapped. That includes 16, 32, and 64bit signed and unsigned
4746 * integers as well as file handles and double precision floating point
4747 * values.
4748 *
4749 * This function is an identity mapping on any value that does not
4750 * contain multi-byte numeric data. That include strings, booleans,
4751 * bytes and containers containing only these things (recursively).
4752 *
4753 * The returned value is always in normal form and is marked as trusted.
4754 *
4755 * Since: 2.24
4756 **/
4757 GVariant *
4758 g_variant_byteswap (GVariant *value)
4759 {
4760 GVariantTypeInfo *type_info;
4761 guint alignment;
4762 GVariant *new;
4763
4764 type_info = g_variant_get_type_info (value);
4765
4766 g_variant_type_info_query (type_info, &alignment, NULL);
4767
4768 if (alignment)
4769 /* (potentially) contains multi-byte numeric data */
4770 {
4771 GVariantSerialised serialised;
4772 GVariant *trusted;
4773 GBuffer *buffer;
4774
4775 trusted = g_variant_get_normal_form (value);
4776 serialised.type_info = g_variant_get_type_info (trusted);
4777 serialised.size = g_variant_get_size (trusted);
4778 serialised.data = g_malloc (serialised.size);
4779 g_variant_store (trusted, serialised.data);
4780 g_variant_unref (trusted);
4781
4782 g_variant_serialised_byteswap (serialised);
4783
4784 buffer = g_buffer_new_take_data (serialised.data, serialised.size);
4785 #ifdef GSTREAMER_LITE
4786 if (buffer == NULL) {
4787 return NULL;
4788 }
4789 #endif // GSTREAMER_LITE
4790 new = g_variant_new_from_buffer (g_variant_get_type (value), buffer, TRUE);
4791 g_buffer_unref (buffer);
4792 }
4793 else
4794 /* contains no multi-byte data */
4795 new = value;
4796
4797 return g_variant_ref_sink (new);
4798 }
4799
4800 /**
4801 * g_variant_new_from_data:
4802 * @type: a definite #GVariantType
4803 * @data: (array length=size) (element-type guint8): the serialised data
4804 * @size: the size of @data
4805 * @trusted: %TRUE if @data is definitely in normal form
4806 * @notify: (scope async): function to call when @data is no longer needed
4807 * @user_data: data for @notify
4808 * @returns: (transfer none): a new floating #GVariant of type @type
4809 *
4810 * Creates a new #GVariant instance from serialised data.
4811 *
4812 * @type is the type of #GVariant instance that will be constructed.
4813 * The interpretation of @data depends on knowing the type.
4814 *
4815 * @data is not modified by this function and must remain valid with an
4816 * unchanging value until such a time as @notify is called with
4817 * @user_data. If the contents of @data change before that time then
4818 * the result is undefined.
4819 *
4820 * If @data is trusted to be serialised data in normal form then
4821 * @trusted should be %TRUE. This applies to serialised data created
4822 * within this process or read from a trusted location on the disk (such
4823 * as a file installed in /usr/lib alongside your application). You
4824 * should set trusted to %FALSE if @data is read from the network, a
4825 * file in the user's home directory, etc.
4826 *
4827 * @notify will be called with @user_data when @data is no longer
4828 * needed. The exact time of this call is unspecified and might even be
4829 * before this function returns.
4830 *
4831 * Since: 2.24
4832 **/
4833 GVariant *
4834 g_variant_new_from_data (const GVariantType *type,
4835 gconstpointer data,
4836 gsize size,
4837 gboolean trusted,
4838 GDestroyNotify notify,
4839 gpointer user_data)
4840 {
4841 GVariant *value;
4842 GBuffer *buffer;
4843
4844 g_return_val_if_fail (g_variant_type_is_definite (type), NULL);
4845 g_return_val_if_fail (data != NULL || size == 0, NULL);
4846
4847 if (notify)
4848 buffer = g_buffer_new_from_pointer (data, size, notify, user_data);
4849 else
4850 buffer = g_buffer_new_from_static_data (data, size);
4851
4852 value = g_variant_new_from_buffer (type, buffer, trusted);
4853 g_buffer_unref (buffer);
4854
4855 return value;
4856 }
4857
4858 /* Epilogue {{{1 */
4859 /* vim:set foldmethod=marker: */