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 2.1 of the License, 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, see <http://www.gnu.org/licenses/>.
17 *
18 * Author: Ryan Lortie <desrt@desrt.ca>
19 */
20
21 /* Prologue {{{1 */
22
23 #include "config.h"
24
25 #include <glib/gvariant-serialiser.h>
26 #include "gvariant-internal.h"
27 #include <glib/gvariant-core.h>
28 #include <glib/gtestutils.h>
29 #include <glib/gstrfuncs.h>
30 #include <glib/gslice.h>
31 #include <glib/ghash.h>
32 #include <glib/gmem.h>
33
34 #include <string.h>
35
36
37 /**
38 * SECTION:gvariant
39 * @title: GVariant
40 * @short_description: strongly typed value datatype
41 * @see_also: GVariantType
42 *
43 * #GVariant is a variant datatype; it can contain one or more values
44 * along with information about the type of the values.
45 *
46 * A #GVariant may contain simple types, like an integer, or a boolean value;
47 * or complex types, like an array of two strings, or a dictionary of key
48 * value pairs. A #GVariant is also immutable: once it's been created neither
49 * its type nor its content can be modified further.
50 *
51 * GVariant is useful whenever data needs to be serialized, for example when
52 * sending method parameters in D-Bus, or when saving settings using GSettings.
53 *
54 * When creating a new #GVariant, you pass the data you want to store in it
55 * along with a string representing the type of data you wish to pass to it.
56 *
57 * For instance, if you want to create a #GVariant holding an integer value you
58 * can use:
59 *
60 * |[<!-- language="C" -->
61 * GVariant *v = g_variant_new ("u", 40);
62 * ]|
63 *
64 * The string "u" in the first argument tells #GVariant that the data passed to
65 * the constructor (40) is going to be an unsigned integer.
66 *
67 * More advanced examples of #GVariant in use can be found in documentation for
68 * [GVariant format strings][gvariant-format-strings-pointers].
69 *
70 * The range of possible values is determined by the type.
71 *
72 * The type system used by #GVariant is #GVariantType.
73 *
74 * #GVariant instances always have a type and a value (which are given
75 * at construction time). The type and value of a #GVariant instance
76 * can never change other than by the #GVariant itself being
77 * destroyed. A #GVariant cannot contain a pointer.
78 *
79 * #GVariant is reference counted using g_variant_ref() and
80 * g_variant_unref(). #GVariant also has floating reference counts --
81 * see g_variant_ref_sink().
82 *
83 * #GVariant is completely threadsafe. A #GVariant instance can be
84 * concurrently accessed in any way from any number of threads without
85 * problems.
86 *
87 * #GVariant is heavily optimised for dealing with data in serialized
88 * form. It works particularly well with data located in memory-mapped
89 * files. It can perform nearly all deserialization operations in a
90 * small constant time, usually touching only a single memory page.
91 * Serialized #GVariant data can also be sent over the network.
92 *
93 * #GVariant is largely compatible with D-Bus. Almost all types of
94 * #GVariant instances can be sent over D-Bus. See #GVariantType for
95 * exceptions. (However, #GVariant's serialization format is not the same
96 * as the serialization format of a D-Bus message body: use #GDBusMessage,
97 * in the gio library, for those.)
98 *
99 * For space-efficiency, the #GVariant serialization format does not
100 * automatically include the variant's length, type or endianness,
101 * which must either be implied from context (such as knowledge that a
102 * particular file format always contains a little-endian
103 * %G_VARIANT_TYPE_VARIANT which occupies the whole length of the file)
104 * or supplied out-of-band (for instance, a length, type and/or endianness
105 * indicator could be placed at the beginning of a file, network message
106 * or network stream).
107 *
108 * A #GVariant's size is limited mainly by any lower level operating
109 * system constraints, such as the number of bits in #gsize. For
110 * example, it is reasonable to have a 2GB file mapped into memory
111 * with #GMappedFile, and call g_variant_new_from_data() on it.
112 *
113 * For convenience to C programmers, #GVariant features powerful
114 * varargs-based value construction and destruction. This feature is
115 * designed to be embedded in other libraries.
116 *
117 * There is a Python-inspired text language for describing #GVariant
118 * values. #GVariant includes a printer for this language and a parser
119 * with type inferencing.
120 *
121 * ## Memory Use
122 *
123 * #GVariant tries to be quite efficient with respect to memory use.
124 * This section gives a rough idea of how much memory is used by the
125 * current implementation. The information here is subject to change
126 * in the future.
127 *
128 * The memory allocated by #GVariant can be grouped into 4 broad
129 * purposes: memory for serialized data, memory for the type
130 * information cache, buffer management memory and memory for the
131 * #GVariant structure itself.
132 *
133 * ## Serialized Data Memory
134 *
135 * This is the memory that is used for storing GVariant data in
136 * serialized form. This is what would be sent over the network or
137 * what would end up on disk, not counting any indicator of the
138 * endianness, or of the length or type of the top-level variant.
139 *
140 * The amount of memory required to store a boolean is 1 byte. 16,
141 * 32 and 64 bit integers and double precision floating point numbers
142 * use their "natural" size. Strings (including object path and
143 * signature strings) are stored with a nul terminator, and as such
144 * use the length of the string plus 1 byte.
145 *
146 * Maybe types use no space at all to represent the null value and
147 * use the same amount of space (sometimes plus one byte) as the
148 * equivalent non-maybe-typed value to represent the non-null case.
149 *
150 * Arrays use the amount of space required to store each of their
151 * members, concatenated. Additionally, if the items stored in an
152 * array are not of a fixed-size (ie: strings, other arrays, etc)
153 * then an additional framing offset is stored for each item. The
154 * size of this offset is either 1, 2 or 4 bytes depending on the
155 * overall size of the container. Additionally, extra padding bytes
156 * are added as required for alignment of child values.
157 *
158 * Tuples (including dictionary entries) use the amount of space
159 * required to store each of their members, concatenated, plus one
160 * framing offset (as per arrays) for each non-fixed-sized item in
161 * the tuple, except for the last one. Additionally, extra padding
162 * bytes are added as required for alignment of child values.
163 *
164 * Variants use the same amount of space as the item inside of the
165 * variant, plus 1 byte, plus the length of the type string for the
166 * item inside the variant.
167 *
168 * As an example, consider a dictionary mapping strings to variants.
169 * In the case that the dictionary is empty, 0 bytes are required for
170 * the serialization.
171 *
172 * If we add an item "width" that maps to the int32 value of 500 then
173 * we will use 4 byte to store the int32 (so 6 for the variant
174 * containing it) and 6 bytes for the string. The variant must be
175 * aligned to 8 after the 6 bytes of the string, so that's 2 extra
176 * bytes. 6 (string) + 2 (padding) + 6 (variant) is 14 bytes used
177 * for the dictionary entry. An additional 1 byte is added to the
178 * array as a framing offset making a total of 15 bytes.
179 *
180 * If we add another entry, "title" that maps to a nullable string
181 * that happens to have a value of null, then we use 0 bytes for the
182 * null value (and 3 bytes for the variant to contain it along with
183 * its type string) plus 6 bytes for the string. Again, we need 2
184 * padding bytes. That makes a total of 6 + 2 + 3 = 11 bytes.
185 *
186 * We now require extra padding between the two items in the array.
187 * After the 14 bytes of the first item, that's 2 bytes required.
188 * We now require 2 framing offsets for an extra two
189 * bytes. 14 + 2 + 11 + 2 = 29 bytes to encode the entire two-item
190 * dictionary.
191 *
192 * ## Type Information Cache
193 *
194 * For each GVariant type that currently exists in the program a type
195 * information structure is kept in the type information cache. The
196 * type information structure is required for rapid deserialization.
197 *
198 * Continuing with the above example, if a #GVariant exists with the
199 * type "a{sv}" then a type information struct will exist for
200 * "a{sv}", "{sv}", "s", and "v". Multiple uses of the same type
201 * will share the same type information. Additionally, all
202 * single-digit types are stored in read-only static memory and do
203 * not contribute to the writable memory footprint of a program using
204 * #GVariant.
205 *
206 * Aside from the type information structures stored in read-only
207 * memory, there are two forms of type information. One is used for
208 * container types where there is a single element type: arrays and
209 * maybe types. The other is used for container types where there
210 * are multiple element types: tuples and dictionary entries.
211 *
212 * Array type info structures are 6 * sizeof (void *), plus the
213 * memory required to store the type string itself. This means that
214 * on 32-bit systems, the cache entry for "a{sv}" would require 30
215 * bytes of memory (plus malloc overhead).
216 *
217 * Tuple type info structures are 6 * sizeof (void *), plus 4 *
218 * sizeof (void *) for each item in the tuple, plus the memory
219 * required to store the type string itself. A 2-item tuple, for
220 * example, would have a type information structure that consumed
221 * writable memory in the size of 14 * sizeof (void *) (plus type
222 * string) This means that on 32-bit systems, the cache entry for
223 * "{sv}" would require 61 bytes of memory (plus malloc overhead).
224 *
225 * This means that in total, for our "a{sv}" example, 91 bytes of
226 * type information would be allocated.
227 *
228 * The type information cache, additionally, uses a #GHashTable to
229 * store and look up the cached items and stores a pointer to this
230 * hash table in static storage. The hash table is freed when there
231 * are zero items in the type cache.
232 *
233 * Although these sizes may seem large it is important to remember
234 * that a program will probably only have a very small number of
235 * different types of values in it and that only one type information
236 * structure is required for many different values of the same type.
237 *
238 * ## Buffer Management Memory
239 *
240 * #GVariant uses an internal buffer management structure to deal
241 * with the various different possible sources of serialized data
242 * that it uses. The buffer is responsible for ensuring that the
243 * correct call is made when the data is no longer in use by
244 * #GVariant. This may involve a g_free() or a g_slice_free() or
245 * even g_mapped_file_unref().
246 *
247 * One buffer management structure is used for each chunk of
248 * serialized data. The size of the buffer management structure
249 * is 4 * (void *). On 32-bit systems, that's 16 bytes.
250 *
251 * ## GVariant structure
252 *
253 * The size of a #GVariant structure is 6 * (void *). On 32-bit
254 * systems, that's 24 bytes.
255 *
256 * #GVariant structures only exist if they are explicitly created
257 * with API calls. For example, if a #GVariant is constructed out of
258 * serialized data for the example given above (with the dictionary)
259 * then although there are 9 individual values that comprise the
260 * entire dictionary (two keys, two values, two variants containing
261 * the values, two dictionary entries, plus the dictionary itself),
262 * only 1 #GVariant instance exists -- the one referring to the
263 * dictionary.
264 *
265 * If calls are made to start accessing the other values then
266 * #GVariant instances will exist for those values only for as long
267 * as they are in use (ie: until you call g_variant_unref()). The
268 * type information is shared. The serialized data and the buffer
269 * management structure for that serialized data is shared by the
270 * child.
271 *
272 * ## Summary
273 *
274 * To put the entire example together, for our dictionary mapping
275 * strings to variants (with two entries, as given above), we are
276 * using 91 bytes of memory for type information, 29 bytes of memory
277 * for the serialized data, 16 bytes for buffer management and 24
278 * bytes for the #GVariant instance, or a total of 160 bytes, plus
279 * malloc overhead. If we were to use g_variant_get_child_value() to
280 * access the two dictionary entries, we would use an additional 48
281 * bytes. If we were to have other dictionaries of the same type, we
282 * would use more memory for the serialized data and buffer
283 * management for those dictionaries, but the type information would
284 * be shared.
285 */
286
287 /* definition of GVariant structure is in gvariant-core.c */
288
289 /* this is a g_return_val_if_fail() for making
290 * sure a (GVariant *) has the required type.
291 */
292 #define TYPE_CHECK(value, TYPE, val) \
293 if G_UNLIKELY (!g_variant_is_of_type (value, TYPE)) { \
294 g_return_if_fail_warning (G_LOG_DOMAIN, G_STRFUNC, \
295 "g_variant_is_of_type (" #value \
296 ", " #TYPE ")"); \
297 return val; \
298 }
299
300 /* Numeric Type Constructor/Getters {{{1 */
301 /* < private >
302 * g_variant_new_from_trusted:
303 * @type: the #GVariantType
304 * @data: the data to use
305 * @size: the size of @data
306 *
307 * Constructs a new trusted #GVariant instance from the provided data.
308 * This is used to implement g_variant_new_* for all the basic types.
309 *
310 * Note: @data must be backed by memory that is aligned appropriately for the
311 * @type being loaded. Otherwise this function will internally create a copy of
312 * the memory (since GLib 2.60) or (in older versions) fail and exit the
313 * process.
314 *
315 * Returns: a new floating #GVariant
316 */
317 static GVariant *
g_variant_new_from_trusted(const GVariantType * type,gconstpointer data,gsize size)318 g_variant_new_from_trusted (const GVariantType *type,
319 gconstpointer data,
320 gsize size)
321 {
322 GVariant *value;
323 GBytes *bytes;
324
325 bytes = g_bytes_new (data, size);
326 value = g_variant_new_from_bytes (type, bytes, TRUE);
327 g_bytes_unref (bytes);
328
329 return value;
330 }
331
332 /**
333 * g_variant_new_boolean:
334 * @value: a #gboolean value
335 *
336 * Creates a new boolean #GVariant instance -- either %TRUE or %FALSE.
337 *
338 * Returns: (transfer none): a floating reference to a new boolean #GVariant instance
339 *
340 * Since: 2.24
341 **/
342 GVariant *
g_variant_new_boolean(gboolean value)343 g_variant_new_boolean (gboolean value)
344 {
345 guchar v = value;
346
347 return g_variant_new_from_trusted (G_VARIANT_TYPE_BOOLEAN, &v, 1);
348 }
349
350 /**
351 * g_variant_get_boolean:
352 * @value: a boolean #GVariant instance
353 *
354 * Returns the boolean value of @value.
355 *
356 * It is an error to call this function with a @value of any type
357 * other than %G_VARIANT_TYPE_BOOLEAN.
358 *
359 * Returns: %TRUE or %FALSE
360 *
361 * Since: 2.24
362 **/
363 gboolean
g_variant_get_boolean(GVariant * value)364 g_variant_get_boolean (GVariant *value)
365 {
366 const guchar *data;
367
368 TYPE_CHECK (value, G_VARIANT_TYPE_BOOLEAN, FALSE);
369
370 data = g_variant_get_data (value);
371
372 return data != NULL ? *data != 0 : FALSE;
373 }
374
375 /* the constructors and accessors for byte, int{16,32,64}, handles and
376 * doubles all look pretty much exactly the same, so we reduce
377 * copy/pasting here.
378 */
379 #define NUMERIC_TYPE(TYPE, type, ctype) \
380 GVariant *g_variant_new_##type (ctype value) { \
381 return g_variant_new_from_trusted (G_VARIANT_TYPE_##TYPE, \
382 &value, sizeof value); \
383 } \
384 ctype g_variant_get_##type (GVariant *value) { \
385 const ctype *data; \
386 TYPE_CHECK (value, G_VARIANT_TYPE_ ## TYPE, 0); \
387 data = g_variant_get_data (value); \
388 return data != NULL ? *data : 0; \
389 }
390
391
392 /**
393 * g_variant_new_byte:
394 * @value: a #guint8 value
395 *
396 * Creates a new byte #GVariant instance.
397 *
398 * Returns: (transfer none): a floating reference to a new byte #GVariant instance
399 *
400 * Since: 2.24
401 **/
402 /**
403 * g_variant_get_byte:
404 * @value: a byte #GVariant instance
405 *
406 * Returns the byte value of @value.
407 *
408 * It is an error to call this function with a @value of any type
409 * other than %G_VARIANT_TYPE_BYTE.
410 *
411 * Returns: a #guint8
412 *
413 * Since: 2.24
414 **/
NUMERIC_TYPE(BYTE,byte,guint8)415 NUMERIC_TYPE (BYTE, byte, guint8)
416
417 /**
418 * g_variant_new_int16:
419 * @value: a #gint16 value
420 *
421 * Creates a new int16 #GVariant instance.
422 *
423 * Returns: (transfer none): a floating reference to a new int16 #GVariant instance
424 *
425 * Since: 2.24
426 **/
427 /**
428 * g_variant_get_int16:
429 * @value: an int16 #GVariant instance
430 *
431 * Returns the 16-bit signed integer value of @value.
432 *
433 * It is an error to call this function with a @value of any type
434 * other than %G_VARIANT_TYPE_INT16.
435 *
436 * Returns: a #gint16
437 *
438 * Since: 2.24
439 **/
440 NUMERIC_TYPE (INT16, int16, gint16)
441
442 /**
443 * g_variant_new_uint16:
444 * @value: a #guint16 value
445 *
446 * Creates a new uint16 #GVariant instance.
447 *
448 * Returns: (transfer none): a floating reference to a new uint16 #GVariant instance
449 *
450 * Since: 2.24
451 **/
452 /**
453 * g_variant_get_uint16:
454 * @value: a uint16 #GVariant instance
455 *
456 * Returns the 16-bit unsigned integer value of @value.
457 *
458 * It is an error to call this function with a @value of any type
459 * other than %G_VARIANT_TYPE_UINT16.
460 *
461 * Returns: a #guint16
462 *
463 * Since: 2.24
464 **/
465 NUMERIC_TYPE (UINT16, uint16, guint16)
466
467 /**
468 * g_variant_new_int32:
469 * @value: a #gint32 value
470 *
471 * Creates a new int32 #GVariant instance.
472 *
473 * Returns: (transfer none): a floating reference to a new int32 #GVariant instance
474 *
475 * Since: 2.24
476 **/
477 /**
478 * g_variant_get_int32:
479 * @value: an int32 #GVariant instance
480 *
481 * Returns the 32-bit signed integer value of @value.
482 *
483 * It is an error to call this function with a @value of any type
484 * other than %G_VARIANT_TYPE_INT32.
485 *
486 * Returns: a #gint32
487 *
488 * Since: 2.24
489 **/
490 NUMERIC_TYPE (INT32, int32, gint32)
491
492 /**
493 * g_variant_new_uint32:
494 * @value: a #guint32 value
495 *
496 * Creates a new uint32 #GVariant instance.
497 *
498 * Returns: (transfer none): a floating reference to a new uint32 #GVariant instance
499 *
500 * Since: 2.24
501 **/
502 /**
503 * g_variant_get_uint32:
504 * @value: a uint32 #GVariant instance
505 *
506 * Returns the 32-bit unsigned integer value of @value.
507 *
508 * It is an error to call this function with a @value of any type
509 * other than %G_VARIANT_TYPE_UINT32.
510 *
511 * Returns: a #guint32
512 *
513 * Since: 2.24
514 **/
515 NUMERIC_TYPE (UINT32, uint32, guint32)
516
517 /**
518 * g_variant_new_int64:
519 * @value: a #gint64 value
520 *
521 * Creates a new int64 #GVariant instance.
522 *
523 * Returns: (transfer none): a floating reference to a new int64 #GVariant instance
524 *
525 * Since: 2.24
526 **/
527 /**
528 * g_variant_get_int64:
529 * @value: an int64 #GVariant instance
530 *
531 * Returns the 64-bit signed integer value of @value.
532 *
533 * It is an error to call this function with a @value of any type
534 * other than %G_VARIANT_TYPE_INT64.
535 *
536 * Returns: a #gint64
537 *
538 * Since: 2.24
539 **/
540 NUMERIC_TYPE (INT64, int64, gint64)
541
542 /**
543 * g_variant_new_uint64:
544 * @value: a #guint64 value
545 *
546 * Creates a new uint64 #GVariant instance.
547 *
548 * Returns: (transfer none): a floating reference to a new uint64 #GVariant instance
549 *
550 * Since: 2.24
551 **/
552 /**
553 * g_variant_get_uint64:
554 * @value: a uint64 #GVariant instance
555 *
556 * Returns the 64-bit unsigned integer value of @value.
557 *
558 * It is an error to call this function with a @value of any type
559 * other than %G_VARIANT_TYPE_UINT64.
560 *
561 * Returns: a #guint64
562 *
563 * Since: 2.24
564 **/
565 NUMERIC_TYPE (UINT64, uint64, guint64)
566
567 /**
568 * g_variant_new_handle:
569 * @value: a #gint32 value
570 *
571 * Creates a new handle #GVariant instance.
572 *
573 * By convention, handles are indexes into an array of file descriptors
574 * that are sent alongside a D-Bus message. If you're not interacting
575 * with D-Bus, you probably don't need them.
576 *
577 * Returns: (transfer none): a floating reference to a new handle #GVariant instance
578 *
579 * Since: 2.24
580 **/
581 /**
582 * g_variant_get_handle:
583 * @value: a handle #GVariant instance
584 *
585 * Returns the 32-bit signed integer value of @value.
586 *
587 * It is an error to call this function with a @value of any type other
588 * than %G_VARIANT_TYPE_HANDLE.
589 *
590 * By convention, handles are indexes into an array of file descriptors
591 * that are sent alongside a D-Bus message. If you're not interacting
592 * with D-Bus, you probably don't need them.
593 *
594 * Returns: a #gint32
595 *
596 * Since: 2.24
597 **/
598 NUMERIC_TYPE (HANDLE, handle, gint32)
599
600 /**
601 * g_variant_new_double:
602 * @value: a #gdouble floating point value
603 *
604 * Creates a new double #GVariant instance.
605 *
606 * Returns: (transfer none): a floating reference to a new double #GVariant instance
607 *
608 * Since: 2.24
609 **/
610 /**
611 * g_variant_get_double:
612 * @value: a double #GVariant instance
613 *
614 * Returns the double precision floating point value of @value.
615 *
616 * It is an error to call this function with a @value of any type
617 * other than %G_VARIANT_TYPE_DOUBLE.
618 *
619 * Returns: a #gdouble
620 *
621 * Since: 2.24
622 **/
623 NUMERIC_TYPE (DOUBLE, double, gdouble)
624
625 /* Container type Constructor / Deconstructors {{{1 */
626 /**
627 * g_variant_new_maybe:
628 * @child_type: (nullable): the #GVariantType of the child, or %NULL
629 * @child: (nullable): the child value, or %NULL
630 *
631 * Depending on if @child is %NULL, either wraps @child inside of a
632 * maybe container or creates a Nothing instance for the given @type.
633 *
634 * At least one of @child_type and @child must be non-%NULL.
635 * If @child_type is non-%NULL then it must be a definite type.
636 * If they are both non-%NULL then @child_type must be the type
637 * of @child.
638 *
639 * If @child is a floating reference (see g_variant_ref_sink()), the new
640 * instance takes ownership of @child.
641 *
642 * Returns: (transfer none): a floating reference to a new #GVariant maybe instance
643 *
644 * Since: 2.24
645 **/
646 GVariant *
647 g_variant_new_maybe (const GVariantType *child_type,
648 GVariant *child)
649 {
650 GVariantType *maybe_type;
651 GVariant *value;
652
653 g_return_val_if_fail (child_type == NULL || g_variant_type_is_definite
654 (child_type), 0);
655 g_return_val_if_fail (child_type != NULL || child != NULL, NULL);
656 g_return_val_if_fail (child_type == NULL || child == NULL ||
657 g_variant_is_of_type (child, child_type),
658 NULL);
659
660 if (child_type == NULL)
661 child_type = g_variant_get_type (child);
662
663 maybe_type = g_variant_type_new_maybe (child_type);
664
665 if (child != NULL)
666 {
667 GVariant **children;
668 gboolean trusted;
669
670 children = g_new (GVariant *, 1);
671 children[0] = g_variant_ref_sink (child);
672 trusted = g_variant_is_trusted (children[0]);
673
674 value = g_variant_new_from_children (maybe_type, children, 1, trusted);
675 }
676 else
677 value = g_variant_new_from_children (maybe_type, NULL, 0, TRUE);
678
679 g_variant_type_free (maybe_type);
680
681 return value;
682 }
683
684 /**
685 * g_variant_get_maybe:
686 * @value: a maybe-typed value
687 *
688 * Given a maybe-typed #GVariant instance, extract its value. If the
689 * value is Nothing, then this function returns %NULL.
690 *
691 * Returns: (nullable) (transfer full): the contents of @value, or %NULL
692 *
693 * Since: 2.24
694 **/
695 GVariant *
g_variant_get_maybe(GVariant * value)696 g_variant_get_maybe (GVariant *value)
697 {
698 TYPE_CHECK (value, G_VARIANT_TYPE_MAYBE, NULL);
699
700 if (g_variant_n_children (value))
701 return g_variant_get_child_value (value, 0);
702
703 return NULL;
704 }
705
706 /**
707 * g_variant_new_variant: (constructor)
708 * @value: a #GVariant instance
709 *
710 * Boxes @value. The result is a #GVariant instance representing a
711 * variant containing the original value.
712 *
713 * If @child is a floating reference (see g_variant_ref_sink()), the new
714 * instance takes ownership of @child.
715 *
716 * Returns: (transfer none): a floating reference to a new variant #GVariant instance
717 *
718 * Since: 2.24
719 **/
720 GVariant *
g_variant_new_variant(GVariant * value)721 g_variant_new_variant (GVariant *value)
722 {
723 g_return_val_if_fail (value != NULL, NULL);
724
725 g_variant_ref_sink (value);
726
727 return g_variant_new_from_children (G_VARIANT_TYPE_VARIANT,
728 g_memdup2 (&value, sizeof value),
729 1, g_variant_is_trusted (value));
730 }
731
732 /**
733 * g_variant_get_variant:
734 * @value: a variant #GVariant instance
735 *
736 * Unboxes @value. The result is the #GVariant instance that was
737 * contained in @value.
738 *
739 * Returns: (transfer full): the item contained in the variant
740 *
741 * Since: 2.24
742 **/
743 GVariant *
g_variant_get_variant(GVariant * value)744 g_variant_get_variant (GVariant *value)
745 {
746 TYPE_CHECK (value, G_VARIANT_TYPE_VARIANT, NULL);
747
748 return g_variant_get_child_value (value, 0);
749 }
750
751 /**
752 * g_variant_new_array:
753 * @child_type: (nullable): the element type of the new array
754 * @children: (nullable) (array length=n_children): an array of
755 * #GVariant pointers, the children
756 * @n_children: the length of @children
757 *
758 * Creates a new #GVariant array from @children.
759 *
760 * @child_type must be non-%NULL if @n_children is zero. Otherwise, the
761 * child type is determined by inspecting the first element of the
762 * @children array. If @child_type is non-%NULL then it must be a
763 * definite type.
764 *
765 * The items of the array are taken from the @children array. No entry
766 * in the @children array may be %NULL.
767 *
768 * All items in the array must have the same type, which must be the
769 * same as @child_type, if given.
770 *
771 * If the @children are floating references (see g_variant_ref_sink()), the
772 * new instance takes ownership of them as if via g_variant_ref_sink().
773 *
774 * Returns: (transfer none): a floating reference to a new #GVariant array
775 *
776 * Since: 2.24
777 **/
778 GVariant *
g_variant_new_array(const GVariantType * child_type,GVariant * const * children,gsize n_children)779 g_variant_new_array (const GVariantType *child_type,
780 GVariant * const *children,
781 gsize n_children)
782 {
783 GVariantType *array_type;
784 GVariant **my_children;
785 gboolean trusted;
786 GVariant *value;
787 gsize i;
788
789 g_return_val_if_fail (n_children > 0 || child_type != NULL, NULL);
790 g_return_val_if_fail (n_children == 0 || children != NULL, NULL);
791 g_return_val_if_fail (child_type == NULL ||
792 g_variant_type_is_definite (child_type), NULL);
793
794 my_children = g_new (GVariant *, n_children);
795 trusted = TRUE;
796
797 if (child_type == NULL)
798 child_type = g_variant_get_type (children[0]);
799 array_type = g_variant_type_new_array (child_type);
800
801 for (i = 0; i < n_children; i++)
802 {
803 if G_UNLIKELY (!g_variant_is_of_type (children[i], child_type))
804 {
805 while (i != 0)
806 g_variant_unref (my_children[--i]);
807 g_free (my_children);
808 g_return_val_if_fail (g_variant_is_of_type (children[i], child_type), NULL);
809 }
810 my_children[i] = g_variant_ref_sink (children[i]);
811 trusted &= g_variant_is_trusted (children[i]);
812 }
813
814 value = g_variant_new_from_children (array_type, my_children,
815 n_children, trusted);
816 g_variant_type_free (array_type);
817
818 return value;
819 }
820
821 /*< private >
822 * g_variant_make_tuple_type:
823 * @children: (array length=n_children): an array of GVariant *
824 * @n_children: the length of @children
825 *
826 * Return the type of a tuple containing @children as its items.
827 **/
828 static GVariantType *
g_variant_make_tuple_type(GVariant * const * children,gsize n_children)829 g_variant_make_tuple_type (GVariant * const *children,
830 gsize n_children)
831 {
832 const GVariantType **types;
833 GVariantType *type;
834 gsize i;
835
836 types = g_new (const GVariantType *, n_children);
837
838 for (i = 0; i < n_children; i++)
839 types[i] = g_variant_get_type (children[i]);
840
841 type = g_variant_type_new_tuple (types, n_children);
842 g_free (types);
843
844 return type;
845 }
846
847 /**
848 * g_variant_new_tuple:
849 * @children: (array length=n_children): the items to make the tuple out of
850 * @n_children: the length of @children
851 *
852 * Creates a new tuple #GVariant out of the items in @children. The
853 * type is determined from the types of @children. No entry in the
854 * @children array may be %NULL.
855 *
856 * If @n_children is 0 then the unit tuple is constructed.
857 *
858 * If the @children are floating references (see g_variant_ref_sink()), the
859 * new instance takes ownership of them as if via g_variant_ref_sink().
860 *
861 * Returns: (transfer none): a floating reference to a new #GVariant tuple
862 *
863 * Since: 2.24
864 **/
865 GVariant *
g_variant_new_tuple(GVariant * const * children,gsize n_children)866 g_variant_new_tuple (GVariant * const *children,
867 gsize n_children)
868 {
869 GVariantType *tuple_type;
870 GVariant **my_children;
871 gboolean trusted;
872 GVariant *value;
873 gsize i;
874
875 g_return_val_if_fail (n_children == 0 || children != NULL, NULL);
876
877 my_children = g_new (GVariant *, n_children);
878 trusted = TRUE;
879
880 for (i = 0; i < n_children; i++)
881 {
882 my_children[i] = g_variant_ref_sink (children[i]);
883 trusted &= g_variant_is_trusted (children[i]);
884 }
885
886 tuple_type = g_variant_make_tuple_type (children, n_children);
887 value = g_variant_new_from_children (tuple_type, my_children,
888 n_children, trusted);
889 g_variant_type_free (tuple_type);
890
891 return value;
892 }
893
894 /*< private >
895 * g_variant_make_dict_entry_type:
896 * @key: a #GVariant, the key
897 * @val: a #GVariant, the value
898 *
899 * Return the type of a dictionary entry containing @key and @val as its
900 * children.
901 **/
902 static GVariantType *
g_variant_make_dict_entry_type(GVariant * key,GVariant * val)903 g_variant_make_dict_entry_type (GVariant *key,
904 GVariant *val)
905 {
906 return g_variant_type_new_dict_entry (g_variant_get_type (key),
907 g_variant_get_type (val));
908 }
909
910 /**
911 * g_variant_new_dict_entry: (constructor)
912 * @key: a basic #GVariant, the key
913 * @value: a #GVariant, the value
914 *
915 * Creates a new dictionary entry #GVariant. @key and @value must be
916 * non-%NULL. @key must be a value of a basic type (ie: not a container).
917 *
918 * If the @key or @value are floating references (see g_variant_ref_sink()),
919 * the new instance takes ownership of them as if via g_variant_ref_sink().
920 *
921 * Returns: (transfer none): a floating reference to a new dictionary entry #GVariant
922 *
923 * Since: 2.24
924 **/
925 GVariant *
g_variant_new_dict_entry(GVariant * key,GVariant * value)926 g_variant_new_dict_entry (GVariant *key,
927 GVariant *value)
928 {
929 GVariantType *dict_type;
930 GVariant **children;
931 gboolean trusted;
932
933 g_return_val_if_fail (key != NULL && value != NULL, NULL);
934 g_return_val_if_fail (!g_variant_is_container (key), NULL);
935
936 children = g_new (GVariant *, 2);
937 children[0] = g_variant_ref_sink (key);
938 children[1] = g_variant_ref_sink (value);
939 trusted = g_variant_is_trusted (key) && g_variant_is_trusted (value);
940
941 dict_type = g_variant_make_dict_entry_type (key, value);
942 value = g_variant_new_from_children (dict_type, children, 2, trusted);
943 g_variant_type_free (dict_type);
944
945 return value;
946 }
947
948 /**
949 * g_variant_lookup: (skip)
950 * @dictionary: a dictionary #GVariant
951 * @key: the key to look up in the dictionary
952 * @format_string: a GVariant format string
953 * @...: the arguments to unpack the value into
954 *
955 * Looks up a value in a dictionary #GVariant.
956 *
957 * This function is a wrapper around g_variant_lookup_value() and
958 * g_variant_get(). In the case that %NULL would have been returned,
959 * this function returns %FALSE. Otherwise, it unpacks the returned
960 * value and returns %TRUE.
961 *
962 * @format_string determines the C types that are used for unpacking
963 * the values and also determines if the values are copied or borrowed,
964 * see the section on
965 * [GVariant format strings][gvariant-format-strings-pointers].
966 *
967 * This function is currently implemented with a linear scan. If you
968 * plan to do many lookups then #GVariantDict may be more efficient.
969 *
970 * Returns: %TRUE if a value was unpacked
971 *
972 * Since: 2.28
973 */
974 gboolean
g_variant_lookup(GVariant * dictionary,const gchar * key,const gchar * format_string,...)975 g_variant_lookup (GVariant *dictionary,
976 const gchar *key,
977 const gchar *format_string,
978 ...)
979 {
980 GVariantType *type;
981 GVariant *value;
982
983 /* flatten */
984 g_variant_get_data (dictionary);
985
986 type = g_variant_format_string_scan_type (format_string, NULL, NULL);
987 value = g_variant_lookup_value (dictionary, key, type);
988 g_variant_type_free (type);
989
990 if (value)
991 {
992 va_list ap;
993
994 va_start (ap, format_string);
995 g_variant_get_va (value, format_string, NULL, &ap);
996 g_variant_unref (value);
997 va_end (ap);
998
999 return TRUE;
1000 }
1001
1002 else
1003 return FALSE;
1004 }
1005
1006 /**
1007 * g_variant_lookup_value:
1008 * @dictionary: a dictionary #GVariant
1009 * @key: the key to look up in the dictionary
1010 * @expected_type: (nullable): a #GVariantType, or %NULL
1011 *
1012 * Looks up a value in a dictionary #GVariant.
1013 *
1014 * This function works with dictionaries of the type a{s*} (and equally
1015 * well with type a{o*}, but we only further discuss the string case
1016 * for sake of clarity).
1017 *
1018 * In the event that @dictionary has the type a{sv}, the @expected_type
1019 * string specifies what type of value is expected to be inside of the
1020 * variant. If the value inside the variant has a different type then
1021 * %NULL is returned. In the event that @dictionary has a value type other
1022 * than v then @expected_type must directly match the value type and it is
1023 * used to unpack the value directly or an error occurs.
1024 *
1025 * In either case, if @key is not found in @dictionary, %NULL is returned.
1026 *
1027 * If the key is found and the value has the correct type, it is
1028 * returned. If @expected_type was specified then any non-%NULL return
1029 * value will have this type.
1030 *
1031 * This function is currently implemented with a linear scan. If you
1032 * plan to do many lookups then #GVariantDict may be more efficient.
1033 *
1034 * Returns: (transfer full): the value of the dictionary key, or %NULL
1035 *
1036 * Since: 2.28
1037 */
1038 GVariant *
g_variant_lookup_value(GVariant * dictionary,const gchar * key,const GVariantType * expected_type)1039 g_variant_lookup_value (GVariant *dictionary,
1040 const gchar *key,
1041 const GVariantType *expected_type)
1042 {
1043 GVariantIter iter;
1044 GVariant *entry;
1045 GVariant *value;
1046
1047 g_return_val_if_fail (g_variant_is_of_type (dictionary,
1048 G_VARIANT_TYPE ("a{s*}")) ||
1049 g_variant_is_of_type (dictionary,
1050 G_VARIANT_TYPE ("a{o*}")),
1051 NULL);
1052
1053 g_variant_iter_init (&iter, dictionary);
1054
1055 while ((entry = g_variant_iter_next_value (&iter)))
1056 {
1057 GVariant *entry_key;
1058 gboolean matches;
1059
1060 entry_key = g_variant_get_child_value (entry, 0);
1061 matches = strcmp (g_variant_get_string (entry_key, NULL), key) == 0;
1062 g_variant_unref (entry_key);
1063
1064 if (matches)
1065 break;
1066
1067 g_variant_unref (entry);
1068 }
1069
1070 if (entry == NULL)
1071 return NULL;
1072
1073 value = g_variant_get_child_value (entry, 1);
1074 g_variant_unref (entry);
1075
1076 if (g_variant_is_of_type (value, G_VARIANT_TYPE_VARIANT))
1077 {
1078 GVariant *tmp;
1079
1080 tmp = g_variant_get_variant (value);
1081 g_variant_unref (value);
1082
1083 if (expected_type && !g_variant_is_of_type (tmp, expected_type))
1084 {
1085 g_variant_unref (tmp);
1086 tmp = NULL;
1087 }
1088
1089 value = tmp;
1090 }
1091
1092 g_return_val_if_fail (expected_type == NULL || value == NULL ||
1093 g_variant_is_of_type (value, expected_type), NULL);
1094
1095 return value;
1096 }
1097
1098 /**
1099 * g_variant_get_fixed_array:
1100 * @value: a #GVariant array with fixed-sized elements
1101 * @n_elements: (out): a pointer to the location to store the number of items
1102 * @element_size: the size of each element
1103 *
1104 * Provides access to the serialized data for an array of fixed-sized
1105 * items.
1106 *
1107 * @value must be an array with fixed-sized elements. Numeric types are
1108 * fixed-size, as are tuples containing only other fixed-sized types.
1109 *
1110 * @element_size must be the size of a single element in the array,
1111 * as given by the section on
1112 * [serialized data memory][gvariant-serialized-data-memory].
1113 *
1114 * In particular, arrays of these fixed-sized types can be interpreted
1115 * as an array of the given C type, with @element_size set to the size
1116 * the appropriate type:
1117 * - %G_VARIANT_TYPE_INT16 (etc.): #gint16 (etc.)
1118 * - %G_VARIANT_TYPE_BOOLEAN: #guchar (not #gboolean!)
1119 * - %G_VARIANT_TYPE_BYTE: #guint8
1120 * - %G_VARIANT_TYPE_HANDLE: #guint32
1121 * - %G_VARIANT_TYPE_DOUBLE: #gdouble
1122 *
1123 * For example, if calling this function for an array of 32-bit integers,
1124 * you might say `sizeof(gint32)`. This value isn't used except for the purpose
1125 * of a double-check that the form of the serialized data matches the caller's
1126 * expectation.
1127 *
1128 * @n_elements, which must be non-%NULL, is set equal to the number of
1129 * items in the array.
1130 *
1131 * Returns: (array length=n_elements) (transfer none): a pointer to
1132 * the fixed array
1133 *
1134 * Since: 2.24
1135 **/
1136 gconstpointer
g_variant_get_fixed_array(GVariant * value,gsize * n_elements,gsize element_size)1137 g_variant_get_fixed_array (GVariant *value,
1138 gsize *n_elements,
1139 gsize element_size)
1140 {
1141 GVariantTypeInfo *array_info;
1142 gsize array_element_size;
1143 gconstpointer data;
1144 gsize size;
1145
1146 TYPE_CHECK (value, G_VARIANT_TYPE_ARRAY, NULL);
1147
1148 g_return_val_if_fail (n_elements != NULL, NULL);
1149 g_return_val_if_fail (element_size > 0, NULL);
1150
1151 array_info = g_variant_get_type_info (value);
1152 g_variant_type_info_query_element (array_info, NULL, &array_element_size);
1153
1154 g_return_val_if_fail (array_element_size, NULL);
1155
1156 if G_UNLIKELY (array_element_size != element_size)
1157 {
1158 if (array_element_size)
1159 g_critical ("g_variant_get_fixed_array: assertion "
1160 "'g_variant_array_has_fixed_size (value, element_size)' "
1161 "failed: array size %"G_GSIZE_FORMAT" does not match "
1162 "given element_size %"G_GSIZE_FORMAT".",
1163 array_element_size, element_size);
1164 else
1165 g_critical ("g_variant_get_fixed_array: assertion "
1166 "'g_variant_array_has_fixed_size (value, element_size)' "
1167 "failed: array does not have fixed size.");
1168 }
1169
1170 data = g_variant_get_data (value);
1171 size = g_variant_get_size (value);
1172
1173 if (size % element_size)
1174 *n_elements = 0;
1175 else
1176 *n_elements = size / element_size;
1177
1178 if (*n_elements)
1179 return data;
1180
1181 return NULL;
1182 }
1183
1184 /**
1185 * g_variant_new_fixed_array:
1186 * @element_type: the #GVariantType of each element
1187 * @elements: a pointer to the fixed array of contiguous elements
1188 * @n_elements: the number of elements
1189 * @element_size: the size of each element
1190 *
1191 * Constructs a new array #GVariant instance, where the elements are
1192 * of @element_type type.
1193 *
1194 * @elements must be an array with fixed-sized elements. Numeric types are
1195 * fixed-size as are tuples containing only other fixed-sized types.
1196 *
1197 * @element_size must be the size of a single element in the array.
1198 * For example, if calling this function for an array of 32-bit integers,
1199 * you might say sizeof(gint32). This value isn't used except for the purpose
1200 * of a double-check that the form of the serialized data matches the caller's
1201 * expectation.
1202 *
1203 * @n_elements must be the length of the @elements array.
1204 *
1205 * Returns: (transfer none): a floating reference to a new array #GVariant instance
1206 *
1207 * Since: 2.32
1208 **/
1209 GVariant *
g_variant_new_fixed_array(const GVariantType * element_type,gconstpointer elements,gsize n_elements,gsize element_size)1210 g_variant_new_fixed_array (const GVariantType *element_type,
1211 gconstpointer elements,
1212 gsize n_elements,
1213 gsize element_size)
1214 {
1215 GVariantType *array_type;
1216 gsize array_element_size;
1217 GVariantTypeInfo *array_info;
1218 GVariant *value;
1219 gpointer data;
1220
1221 g_return_val_if_fail (g_variant_type_is_definite (element_type), NULL);
1222 g_return_val_if_fail (element_size > 0, NULL);
1223
1224 array_type = g_variant_type_new_array (element_type);
1225 array_info = g_variant_type_info_get (array_type);
1226 g_variant_type_info_query_element (array_info, NULL, &array_element_size);
1227 if G_UNLIKELY (array_element_size != element_size)
1228 {
1229 if (array_element_size)
1230 g_critical ("g_variant_new_fixed_array: array size %" G_GSIZE_FORMAT
1231 " does not match given element_size %" G_GSIZE_FORMAT ".",
1232 array_element_size, element_size);
1233 else
1234 g_critical ("g_variant_get_fixed_array: array does not have fixed size.");
1235 return NULL;
1236 }
1237
1238 data = g_memdup2 (elements, n_elements * element_size);
1239 value = g_variant_new_from_data (array_type, data,
1240 n_elements * element_size,
1241 FALSE, g_free, data);
1242
1243 g_variant_type_free (array_type);
1244 g_variant_type_info_unref (array_info);
1245
1246 return value;
1247 }
1248
1249 /* String type constructor/getters/validation {{{1 */
1250 /**
1251 * g_variant_new_string:
1252 * @string: a normal UTF-8 nul-terminated string
1253 *
1254 * Creates a string #GVariant with the contents of @string.
1255 *
1256 * @string must be valid UTF-8, and must not be %NULL. To encode
1257 * potentially-%NULL strings, use g_variant_new() with `ms` as the
1258 * [format string][gvariant-format-strings-maybe-types].
1259 *
1260 * Returns: (transfer none): a floating reference to a new string #GVariant instance
1261 *
1262 * Since: 2.24
1263 **/
1264 GVariant *
g_variant_new_string(const gchar * string)1265 g_variant_new_string (const gchar *string)
1266 {
1267 g_return_val_if_fail (string != NULL, NULL);
1268 g_return_val_if_fail (g_utf8_validate (string, -1, NULL), NULL);
1269
1270 return g_variant_new_from_trusted (G_VARIANT_TYPE_STRING,
1271 string, strlen (string) + 1);
1272 }
1273
1274 /**
1275 * g_variant_new_take_string: (skip)
1276 * @string: a normal UTF-8 nul-terminated string
1277 *
1278 * Creates a string #GVariant with the contents of @string.
1279 *
1280 * @string must be valid UTF-8, and must not be %NULL. To encode
1281 * potentially-%NULL strings, use this with g_variant_new_maybe().
1282 *
1283 * This function consumes @string. g_free() will be called on @string
1284 * when it is no longer required.
1285 *
1286 * You must not modify or access @string in any other way after passing
1287 * it to this function. It is even possible that @string is immediately
1288 * freed.
1289 *
1290 * Returns: (transfer none): a floating reference to a new string
1291 * #GVariant instance
1292 *
1293 * Since: 2.38
1294 **/
1295 GVariant *
g_variant_new_take_string(gchar * string)1296 g_variant_new_take_string (gchar *string)
1297 {
1298 GVariant *value;
1299 GBytes *bytes;
1300
1301 g_return_val_if_fail (string != NULL, NULL);
1302 g_return_val_if_fail (g_utf8_validate (string, -1, NULL), NULL);
1303
1304 bytes = g_bytes_new_take (string, strlen (string) + 1);
1305 value = g_variant_new_from_bytes (G_VARIANT_TYPE_STRING, bytes, TRUE);
1306 g_bytes_unref (bytes);
1307
1308 return value;
1309 }
1310
1311 /**
1312 * g_variant_new_printf: (skip)
1313 * @format_string: a printf-style format string
1314 * @...: arguments for @format_string
1315 *
1316 * Creates a string-type GVariant using printf formatting.
1317 *
1318 * This is similar to calling g_strdup_printf() and then
1319 * g_variant_new_string() but it saves a temporary variable and an
1320 * unnecessary copy.
1321 *
1322 * Returns: (transfer none): a floating reference to a new string
1323 * #GVariant instance
1324 *
1325 * Since: 2.38
1326 **/
1327 GVariant *
g_variant_new_printf(const gchar * format_string,...)1328 g_variant_new_printf (const gchar *format_string,
1329 ...)
1330 {
1331 GVariant *value;
1332 GBytes *bytes;
1333 gchar *string;
1334 va_list ap;
1335
1336 g_return_val_if_fail (format_string != NULL, NULL);
1337
1338 va_start (ap, format_string);
1339 string = g_strdup_vprintf (format_string, ap);
1340 va_end (ap);
1341
1342 bytes = g_bytes_new_take (string, strlen (string) + 1);
1343 value = g_variant_new_from_bytes (G_VARIANT_TYPE_STRING, bytes, TRUE);
1344 g_bytes_unref (bytes);
1345
1346 return value;
1347 }
1348
1349 /**
1350 * g_variant_new_object_path:
1351 * @object_path: a normal C nul-terminated string
1352 *
1353 * Creates a D-Bus object path #GVariant with the contents of @string.
1354 * @string must be a valid D-Bus object path. Use
1355 * g_variant_is_object_path() if you're not sure.
1356 *
1357 * Returns: (transfer none): a floating reference to a new object path #GVariant instance
1358 *
1359 * Since: 2.24
1360 **/
1361 GVariant *
g_variant_new_object_path(const gchar * object_path)1362 g_variant_new_object_path (const gchar *object_path)
1363 {
1364 g_return_val_if_fail (g_variant_is_object_path (object_path), NULL);
1365
1366 return g_variant_new_from_trusted (G_VARIANT_TYPE_OBJECT_PATH,
1367 object_path, strlen (object_path) + 1);
1368 }
1369
1370 /**
1371 * g_variant_is_object_path:
1372 * @string: a normal C nul-terminated string
1373 *
1374 * Determines if a given string is a valid D-Bus object path. You
1375 * should ensure that a string is a valid D-Bus object path before
1376 * passing it to g_variant_new_object_path().
1377 *
1378 * A valid object path starts with `/` followed by zero or more
1379 * sequences of characters separated by `/` characters. Each sequence
1380 * must contain only the characters `[A-Z][a-z][0-9]_`. No sequence
1381 * (including the one following the final `/` character) may be empty.
1382 *
1383 * Returns: %TRUE if @string is a D-Bus object path
1384 *
1385 * Since: 2.24
1386 **/
1387 gboolean
g_variant_is_object_path(const gchar * string)1388 g_variant_is_object_path (const gchar *string)
1389 {
1390 g_return_val_if_fail (string != NULL, FALSE);
1391
1392 return g_variant_serialiser_is_object_path (string, strlen (string) + 1);
1393 }
1394
1395 /**
1396 * g_variant_new_signature:
1397 * @signature: a normal C nul-terminated string
1398 *
1399 * Creates a D-Bus type signature #GVariant with the contents of
1400 * @string. @string must be a valid D-Bus type signature. Use
1401 * g_variant_is_signature() if you're not sure.
1402 *
1403 * Returns: (transfer none): a floating reference to a new signature #GVariant instance
1404 *
1405 * Since: 2.24
1406 **/
1407 GVariant *
g_variant_new_signature(const gchar * signature)1408 g_variant_new_signature (const gchar *signature)
1409 {
1410 g_return_val_if_fail (g_variant_is_signature (signature), NULL);
1411
1412 return g_variant_new_from_trusted (G_VARIANT_TYPE_SIGNATURE,
1413 signature, strlen (signature) + 1);
1414 }
1415
1416 /**
1417 * g_variant_is_signature:
1418 * @string: a normal C nul-terminated string
1419 *
1420 * Determines if a given string is a valid D-Bus type signature. You
1421 * should ensure that a string is a valid D-Bus type signature before
1422 * passing it to g_variant_new_signature().
1423 *
1424 * D-Bus type signatures consist of zero or more definite #GVariantType
1425 * strings in sequence.
1426 *
1427 * Returns: %TRUE if @string is a D-Bus type signature
1428 *
1429 * Since: 2.24
1430 **/
1431 gboolean
g_variant_is_signature(const gchar * string)1432 g_variant_is_signature (const gchar *string)
1433 {
1434 g_return_val_if_fail (string != NULL, FALSE);
1435
1436 return g_variant_serialiser_is_signature (string, strlen (string) + 1);
1437 }
1438
1439 /**
1440 * g_variant_get_string:
1441 * @value: a string #GVariant instance
1442 * @length: (optional) (default 0) (out): a pointer to a #gsize,
1443 * to store the length
1444 *
1445 * Returns the string value of a #GVariant instance with a string
1446 * type. This includes the types %G_VARIANT_TYPE_STRING,
1447 * %G_VARIANT_TYPE_OBJECT_PATH and %G_VARIANT_TYPE_SIGNATURE.
1448 *
1449 * The string will always be UTF-8 encoded, will never be %NULL, and will never
1450 * contain nul bytes.
1451 *
1452 * If @length is non-%NULL then the length of the string (in bytes) is
1453 * returned there. For trusted values, this information is already
1454 * known. Untrusted values will be validated and, if valid, a strlen() will be
1455 * performed. If invalid, a default value will be returned — for
1456 * %G_VARIANT_TYPE_OBJECT_PATH, this is `"/"`, and for other types it is the
1457 * empty string.
1458 *
1459 * It is an error to call this function with a @value of any type
1460 * other than those three.
1461 *
1462 * The return value remains valid as long as @value exists.
1463 *
1464 * Returns: (transfer none): the constant string, UTF-8 encoded
1465 *
1466 * Since: 2.24
1467 **/
1468 const gchar *
g_variant_get_string(GVariant * value,gsize * length)1469 g_variant_get_string (GVariant *value,
1470 gsize *length)
1471 {
1472 gconstpointer data;
1473 gsize size;
1474
1475 g_return_val_if_fail (value != NULL, NULL);
1476 g_return_val_if_fail (
1477 g_variant_is_of_type (value, G_VARIANT_TYPE_STRING) ||
1478 g_variant_is_of_type (value, G_VARIANT_TYPE_OBJECT_PATH) ||
1479 g_variant_is_of_type (value, G_VARIANT_TYPE_SIGNATURE), NULL);
1480
1481 data = g_variant_get_data (value);
1482 size = g_variant_get_size (value);
1483
1484 if (!g_variant_is_trusted (value))
1485 {
1486 switch (g_variant_classify (value))
1487 {
1488 case G_VARIANT_CLASS_STRING:
1489 if (g_variant_serialiser_is_string (data, size))
1490 break;
1491
1492 data = "";
1493 size = 1;
1494 break;
1495
1496 case G_VARIANT_CLASS_OBJECT_PATH:
1497 if (g_variant_serialiser_is_object_path (data, size))
1498 break;
1499
1500 data = "/";
1501 size = 2;
1502 break;
1503
1504 case G_VARIANT_CLASS_SIGNATURE:
1505 if (g_variant_serialiser_is_signature (data, size))
1506 break;
1507
1508 data = "";
1509 size = 1;
1510 break;
1511
1512 default:
1513 g_assert_not_reached ();
1514 }
1515 }
1516
1517 if (length)
1518 *length = size - 1;
1519
1520 return data;
1521 }
1522
1523 /**
1524 * g_variant_dup_string:
1525 * @value: a string #GVariant instance
1526 * @length: (out): a pointer to a #gsize, to store the length
1527 *
1528 * Similar to g_variant_get_string() except that instead of returning
1529 * a constant string, the string is duplicated.
1530 *
1531 * The string will always be UTF-8 encoded.
1532 *
1533 * The return value must be freed using g_free().
1534 *
1535 * Returns: (transfer full): a newly allocated string, UTF-8 encoded
1536 *
1537 * Since: 2.24
1538 **/
1539 gchar *
g_variant_dup_string(GVariant * value,gsize * length)1540 g_variant_dup_string (GVariant *value,
1541 gsize *length)
1542 {
1543 return g_strdup (g_variant_get_string (value, length));
1544 }
1545
1546 /**
1547 * g_variant_new_strv:
1548 * @strv: (array length=length) (element-type utf8): an array of strings
1549 * @length: the length of @strv, or -1
1550 *
1551 * Constructs an array of strings #GVariant from the given array of
1552 * strings.
1553 *
1554 * If @length is -1 then @strv is %NULL-terminated.
1555 *
1556 * Returns: (transfer none): a new floating #GVariant instance
1557 *
1558 * Since: 2.24
1559 **/
1560 GVariant *
g_variant_new_strv(const gchar * const * strv,gssize length)1561 g_variant_new_strv (const gchar * const *strv,
1562 gssize length)
1563 {
1564 GVariant **strings;
1565 gsize i, length_unsigned;
1566
1567 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1568
1569 if (length < 0)
1570 length = g_strv_length ((gchar **) strv);
1571 length_unsigned = length;
1572
1573 strings = g_new (GVariant *, length_unsigned);
1574 for (i = 0; i < length_unsigned; i++)
1575 strings[i] = g_variant_ref_sink (g_variant_new_string (strv[i]));
1576
1577 return g_variant_new_from_children (G_VARIANT_TYPE_STRING_ARRAY,
1578 strings, length_unsigned, TRUE);
1579 }
1580
1581 /**
1582 * g_variant_get_strv:
1583 * @value: an array of strings #GVariant
1584 * @length: (out) (optional): the length of the result, or %NULL
1585 *
1586 * Gets the contents of an array of strings #GVariant. This call
1587 * makes a shallow copy; the return result should be released with
1588 * g_free(), but the individual strings must not be modified.
1589 *
1590 * If @length is non-%NULL then the number of elements in the result
1591 * is stored there. In any case, the resulting array will be
1592 * %NULL-terminated.
1593 *
1594 * For an empty array, @length will be set to 0 and a pointer to a
1595 * %NULL pointer will be returned.
1596 *
1597 * Returns: (array length=length zero-terminated=1) (transfer container): an array of constant strings
1598 *
1599 * Since: 2.24
1600 **/
1601 const gchar **
g_variant_get_strv(GVariant * value,gsize * length)1602 g_variant_get_strv (GVariant *value,
1603 gsize *length)
1604 {
1605 const gchar **strv;
1606 gsize n;
1607 gsize i;
1608
1609 TYPE_CHECK (value, G_VARIANT_TYPE_STRING_ARRAY, NULL);
1610
1611 g_variant_get_data (value);
1612 n = g_variant_n_children (value);
1613 strv = g_new (const gchar *, n + 1);
1614
1615 for (i = 0; i < n; i++)
1616 {
1617 GVariant *string;
1618
1619 string = g_variant_get_child_value (value, i);
1620 strv[i] = g_variant_get_string (string, NULL);
1621 g_variant_unref (string);
1622 }
1623 strv[i] = NULL;
1624
1625 if (length)
1626 *length = n;
1627
1628 return strv;
1629 }
1630
1631 /**
1632 * g_variant_dup_strv:
1633 * @value: an array of strings #GVariant
1634 * @length: (out) (optional): the length of the result, or %NULL
1635 *
1636 * Gets the contents of an array of strings #GVariant. This call
1637 * makes a deep copy; the return result should be released with
1638 * g_strfreev().
1639 *
1640 * If @length is non-%NULL then the number of elements in the result
1641 * is stored there. In any case, the resulting array will be
1642 * %NULL-terminated.
1643 *
1644 * For an empty array, @length will be set to 0 and a pointer to a
1645 * %NULL pointer will be returned.
1646 *
1647 * Returns: (array length=length zero-terminated=1) (transfer full): an array of strings
1648 *
1649 * Since: 2.24
1650 **/
1651 gchar **
g_variant_dup_strv(GVariant * value,gsize * length)1652 g_variant_dup_strv (GVariant *value,
1653 gsize *length)
1654 {
1655 gchar **strv;
1656 gsize n;
1657 gsize i;
1658
1659 TYPE_CHECK (value, G_VARIANT_TYPE_STRING_ARRAY, NULL);
1660
1661 n = g_variant_n_children (value);
1662 strv = g_new (gchar *, n + 1);
1663
1664 for (i = 0; i < n; i++)
1665 {
1666 GVariant *string;
1667
1668 string = g_variant_get_child_value (value, i);
1669 strv[i] = g_variant_dup_string (string, NULL);
1670 g_variant_unref (string);
1671 }
1672 strv[i] = NULL;
1673
1674 if (length)
1675 *length = n;
1676
1677 return strv;
1678 }
1679
1680 /**
1681 * g_variant_new_objv:
1682 * @strv: (array length=length) (element-type utf8): an array of strings
1683 * @length: the length of @strv, or -1
1684 *
1685 * Constructs an array of object paths #GVariant from the given array of
1686 * strings.
1687 *
1688 * Each string must be a valid #GVariant object path; see
1689 * g_variant_is_object_path().
1690 *
1691 * If @length is -1 then @strv is %NULL-terminated.
1692 *
1693 * Returns: (transfer none): a new floating #GVariant instance
1694 *
1695 * Since: 2.30
1696 **/
1697 GVariant *
g_variant_new_objv(const gchar * const * strv,gssize length)1698 g_variant_new_objv (const gchar * const *strv,
1699 gssize length)
1700 {
1701 GVariant **strings;
1702 gsize i, length_unsigned;
1703
1704 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1705
1706 if (length < 0)
1707 length = g_strv_length ((gchar **) strv);
1708 length_unsigned = length;
1709
1710 strings = g_new (GVariant *, length_unsigned);
1711 for (i = 0; i < length_unsigned; i++)
1712 strings[i] = g_variant_ref_sink (g_variant_new_object_path (strv[i]));
1713
1714 return g_variant_new_from_children (G_VARIANT_TYPE_OBJECT_PATH_ARRAY,
1715 strings, length_unsigned, TRUE);
1716 }
1717
1718 /**
1719 * g_variant_get_objv:
1720 * @value: an array of object paths #GVariant
1721 * @length: (out) (optional): the length of the result, or %NULL
1722 *
1723 * Gets the contents of an array of object paths #GVariant. This call
1724 * makes a shallow copy; the return result should be released with
1725 * g_free(), but the individual strings must not be modified.
1726 *
1727 * If @length is non-%NULL then the number of elements in the result
1728 * is stored there. In any case, the resulting array will be
1729 * %NULL-terminated.
1730 *
1731 * For an empty array, @length will be set to 0 and a pointer to a
1732 * %NULL pointer will be returned.
1733 *
1734 * Returns: (array length=length zero-terminated=1) (transfer container): an array of constant strings
1735 *
1736 * Since: 2.30
1737 **/
1738 const gchar **
g_variant_get_objv(GVariant * value,gsize * length)1739 g_variant_get_objv (GVariant *value,
1740 gsize *length)
1741 {
1742 const gchar **strv;
1743 gsize n;
1744 gsize i;
1745
1746 TYPE_CHECK (value, G_VARIANT_TYPE_OBJECT_PATH_ARRAY, NULL);
1747
1748 g_variant_get_data (value);
1749 n = g_variant_n_children (value);
1750 strv = g_new (const gchar *, n + 1);
1751
1752 for (i = 0; i < n; i++)
1753 {
1754 GVariant *string;
1755
1756 string = g_variant_get_child_value (value, i);
1757 strv[i] = g_variant_get_string (string, NULL);
1758 g_variant_unref (string);
1759 }
1760 strv[i] = NULL;
1761
1762 if (length)
1763 *length = n;
1764
1765 return strv;
1766 }
1767
1768 /**
1769 * g_variant_dup_objv:
1770 * @value: an array of object paths #GVariant
1771 * @length: (out) (optional): the length of the result, or %NULL
1772 *
1773 * Gets the contents of an array of object paths #GVariant. This call
1774 * makes a deep copy; the return result should be released with
1775 * g_strfreev().
1776 *
1777 * If @length is non-%NULL then the number of elements in the result
1778 * is stored there. In any case, the resulting array will be
1779 * %NULL-terminated.
1780 *
1781 * For an empty array, @length will be set to 0 and a pointer to a
1782 * %NULL pointer will be returned.
1783 *
1784 * Returns: (array length=length zero-terminated=1) (transfer full): an array of strings
1785 *
1786 * Since: 2.30
1787 **/
1788 gchar **
g_variant_dup_objv(GVariant * value,gsize * length)1789 g_variant_dup_objv (GVariant *value,
1790 gsize *length)
1791 {
1792 gchar **strv;
1793 gsize n;
1794 gsize i;
1795
1796 TYPE_CHECK (value, G_VARIANT_TYPE_OBJECT_PATH_ARRAY, NULL);
1797
1798 n = g_variant_n_children (value);
1799 strv = g_new (gchar *, n + 1);
1800
1801 for (i = 0; i < n; i++)
1802 {
1803 GVariant *string;
1804
1805 string = g_variant_get_child_value (value, i);
1806 strv[i] = g_variant_dup_string (string, NULL);
1807 g_variant_unref (string);
1808 }
1809 strv[i] = NULL;
1810
1811 if (length)
1812 *length = n;
1813
1814 return strv;
1815 }
1816
1817
1818 /**
1819 * g_variant_new_bytestring:
1820 * @string: (array zero-terminated=1) (element-type guint8): a normal
1821 * nul-terminated string in no particular encoding
1822 *
1823 * Creates an array-of-bytes #GVariant with the contents of @string.
1824 * This function is just like g_variant_new_string() except that the
1825 * string need not be valid UTF-8.
1826 *
1827 * The nul terminator character at the end of the string is stored in
1828 * the array.
1829 *
1830 * Returns: (transfer none): a floating reference to a new bytestring #GVariant instance
1831 *
1832 * Since: 2.26
1833 **/
1834 GVariant *
g_variant_new_bytestring(const gchar * string)1835 g_variant_new_bytestring (const gchar *string)
1836 {
1837 g_return_val_if_fail (string != NULL, NULL);
1838
1839 return g_variant_new_from_trusted (G_VARIANT_TYPE_BYTESTRING,
1840 string, strlen (string) + 1);
1841 }
1842
1843 /**
1844 * g_variant_get_bytestring:
1845 * @value: an array-of-bytes #GVariant instance
1846 *
1847 * Returns the string value of a #GVariant instance with an
1848 * array-of-bytes type. The string has no particular encoding.
1849 *
1850 * If the array does not end with a nul terminator character, the empty
1851 * string is returned. For this reason, you can always trust that a
1852 * non-%NULL nul-terminated string will be returned by this function.
1853 *
1854 * If the array contains a nul terminator character somewhere other than
1855 * the last byte then the returned string is the string, up to the first
1856 * such nul character.
1857 *
1858 * g_variant_get_fixed_array() should be used instead if the array contains
1859 * arbitrary data that could not be nul-terminated or could contain nul bytes.
1860 *
1861 * It is an error to call this function with a @value that is not an
1862 * array of bytes.
1863 *
1864 * The return value remains valid as long as @value exists.
1865 *
1866 * Returns: (transfer none) (array zero-terminated=1) (element-type guint8):
1867 * the constant string
1868 *
1869 * Since: 2.26
1870 **/
1871 const gchar *
g_variant_get_bytestring(GVariant * value)1872 g_variant_get_bytestring (GVariant *value)
1873 {
1874 const gchar *string;
1875 gsize size;
1876
1877 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING, NULL);
1878
1879 /* Won't be NULL since this is an array type */
1880 string = g_variant_get_data (value);
1881 size = g_variant_get_size (value);
1882
1883 if (size && string[size - 1] == '\0')
1884 return string;
1885 else
1886 return "";
1887 }
1888
1889 /**
1890 * g_variant_dup_bytestring:
1891 * @value: an array-of-bytes #GVariant instance
1892 * @length: (out) (optional) (default NULL): a pointer to a #gsize, to store
1893 * the length (not including the nul terminator)
1894 *
1895 * Similar to g_variant_get_bytestring() except that instead of
1896 * returning a constant string, the string is duplicated.
1897 *
1898 * The return value must be freed using g_free().
1899 *
1900 * Returns: (transfer full) (array zero-terminated=1 length=length) (element-type guint8):
1901 * a newly allocated string
1902 *
1903 * Since: 2.26
1904 **/
1905 gchar *
g_variant_dup_bytestring(GVariant * value,gsize * length)1906 g_variant_dup_bytestring (GVariant *value,
1907 gsize *length)
1908 {
1909 const gchar *original = g_variant_get_bytestring (value);
1910 gsize size;
1911
1912 /* don't crash in case get_bytestring() had an assert failure */
1913 if (original == NULL)
1914 return NULL;
1915
1916 size = strlen (original);
1917
1918 if (length)
1919 *length = size;
1920
1921 return g_memdup2 (original, size + 1);
1922 }
1923
1924 /**
1925 * g_variant_new_bytestring_array:
1926 * @strv: (array length=length): an array of strings
1927 * @length: the length of @strv, or -1
1928 *
1929 * Constructs an array of bytestring #GVariant from the given array of
1930 * strings.
1931 *
1932 * If @length is -1 then @strv is %NULL-terminated.
1933 *
1934 * Returns: (transfer none): a new floating #GVariant instance
1935 *
1936 * Since: 2.26
1937 **/
1938 GVariant *
g_variant_new_bytestring_array(const gchar * const * strv,gssize length)1939 g_variant_new_bytestring_array (const gchar * const *strv,
1940 gssize length)
1941 {
1942 GVariant **strings;
1943 gsize i, length_unsigned;
1944
1945 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1946
1947 if (length < 0)
1948 length = g_strv_length ((gchar **) strv);
1949 length_unsigned = length;
1950
1951 strings = g_new (GVariant *, length_unsigned);
1952 for (i = 0; i < length_unsigned; i++)
1953 strings[i] = g_variant_ref_sink (g_variant_new_bytestring (strv[i]));
1954
1955 return g_variant_new_from_children (G_VARIANT_TYPE_BYTESTRING_ARRAY,
1956 strings, length_unsigned, TRUE);
1957 }
1958
1959 /**
1960 * g_variant_get_bytestring_array:
1961 * @value: an array of array of bytes #GVariant ('aay')
1962 * @length: (out) (optional): the length of the result, or %NULL
1963 *
1964 * Gets the contents of an array of array of bytes #GVariant. This call
1965 * makes a shallow copy; the return result should be released with
1966 * g_free(), but the individual strings must not be modified.
1967 *
1968 * If @length is non-%NULL then the number of elements in the result is
1969 * stored there. In any case, the resulting array will be
1970 * %NULL-terminated.
1971 *
1972 * For an empty array, @length will be set to 0 and a pointer to a
1973 * %NULL pointer will be returned.
1974 *
1975 * Returns: (array length=length) (transfer container): an array of constant strings
1976 *
1977 * Since: 2.26
1978 **/
1979 const gchar **
g_variant_get_bytestring_array(GVariant * value,gsize * length)1980 g_variant_get_bytestring_array (GVariant *value,
1981 gsize *length)
1982 {
1983 const gchar **strv;
1984 gsize n;
1985 gsize i;
1986
1987 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL);
1988
1989 g_variant_get_data (value);
1990 n = g_variant_n_children (value);
1991 strv = g_new (const gchar *, n + 1);
1992
1993 for (i = 0; i < n; i++)
1994 {
1995 GVariant *string;
1996
1997 string = g_variant_get_child_value (value, i);
1998 strv[i] = g_variant_get_bytestring (string);
1999 g_variant_unref (string);
2000 }
2001 strv[i] = NULL;
2002
2003 if (length)
2004 *length = n;
2005
2006 return strv;
2007 }
2008
2009 /**
2010 * g_variant_dup_bytestring_array:
2011 * @value: an array of array of bytes #GVariant ('aay')
2012 * @length: (out) (optional): the length of the result, or %NULL
2013 *
2014 * Gets the contents of an array of array of bytes #GVariant. This call
2015 * makes a deep copy; the return result should be released with
2016 * g_strfreev().
2017 *
2018 * If @length is non-%NULL then the number of elements in the result is
2019 * stored there. In any case, the resulting array will be
2020 * %NULL-terminated.
2021 *
2022 * For an empty array, @length will be set to 0 and a pointer to a
2023 * %NULL pointer will be returned.
2024 *
2025 * Returns: (array length=length) (transfer full): an array of strings
2026 *
2027 * Since: 2.26
2028 **/
2029 gchar **
g_variant_dup_bytestring_array(GVariant * value,gsize * length)2030 g_variant_dup_bytestring_array (GVariant *value,
2031 gsize *length)
2032 {
2033 gchar **strv;
2034 gsize n;
2035 gsize i;
2036
2037 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL);
2038
2039 g_variant_get_data (value);
2040 n = g_variant_n_children (value);
2041 strv = g_new (gchar *, n + 1);
2042
2043 for (i = 0; i < n; i++)
2044 {
2045 GVariant *string;
2046
2047 string = g_variant_get_child_value (value, i);
2048 strv[i] = g_variant_dup_bytestring (string, NULL);
2049 g_variant_unref (string);
2050 }
2051 strv[i] = NULL;
2052
2053 if (length)
2054 *length = n;
2055
2056 return strv;
2057 }
2058
2059 /* Type checking and querying {{{1 */
2060 /**
2061 * g_variant_get_type:
2062 * @value: a #GVariant
2063 *
2064 * Determines the type of @value.
2065 *
2066 * The return value is valid for the lifetime of @value and must not
2067 * be freed.
2068 *
2069 * Returns: a #GVariantType
2070 *
2071 * Since: 2.24
2072 **/
2073 const GVariantType *
g_variant_get_type(GVariant * value)2074 g_variant_get_type (GVariant *value)
2075 {
2076 GVariantTypeInfo *type_info;
2077
2078 g_return_val_if_fail (value != NULL, NULL);
2079
2080 type_info = g_variant_get_type_info (value);
2081
2082 return (GVariantType *) g_variant_type_info_get_type_string (type_info);
2083 }
2084
2085 /**
2086 * g_variant_get_type_string:
2087 * @value: a #GVariant
2088 *
2089 * Returns the type string of @value. Unlike the result of calling
2090 * g_variant_type_peek_string(), this string is nul-terminated. This
2091 * string belongs to #GVariant and must not be freed.
2092 *
2093 * Returns: the type string for the type of @value
2094 *
2095 * Since: 2.24
2096 **/
2097 const gchar *
g_variant_get_type_string(GVariant * value)2098 g_variant_get_type_string (GVariant *value)
2099 {
2100 GVariantTypeInfo *type_info;
2101
2102 g_return_val_if_fail (value != NULL, NULL);
2103
2104 type_info = g_variant_get_type_info (value);
2105
2106 return g_variant_type_info_get_type_string (type_info);
2107 }
2108
2109 /**
2110 * g_variant_is_of_type:
2111 * @value: a #GVariant instance
2112 * @type: a #GVariantType
2113 *
2114 * Checks if a value has a type matching the provided type.
2115 *
2116 * Returns: %TRUE if the type of @value matches @type
2117 *
2118 * Since: 2.24
2119 **/
2120 gboolean
g_variant_is_of_type(GVariant * value,const GVariantType * type)2121 g_variant_is_of_type (GVariant *value,
2122 const GVariantType *type)
2123 {
2124 return g_variant_type_is_subtype_of (g_variant_get_type (value), type);
2125 }
2126
2127 /**
2128 * g_variant_is_container:
2129 * @value: a #GVariant instance
2130 *
2131 * Checks if @value is a container.
2132 *
2133 * Returns: %TRUE if @value is a container
2134 *
2135 * Since: 2.24
2136 */
2137 gboolean
g_variant_is_container(GVariant * value)2138 g_variant_is_container (GVariant *value)
2139 {
2140 return g_variant_type_is_container (g_variant_get_type (value));
2141 }
2142
2143
2144 /**
2145 * g_variant_classify:
2146 * @value: a #GVariant
2147 *
2148 * Classifies @value according to its top-level type.
2149 *
2150 * Returns: the #GVariantClass of @value
2151 *
2152 * Since: 2.24
2153 **/
2154 /**
2155 * GVariantClass:
2156 * @G_VARIANT_CLASS_BOOLEAN: The #GVariant is a boolean.
2157 * @G_VARIANT_CLASS_BYTE: The #GVariant is a byte.
2158 * @G_VARIANT_CLASS_INT16: The #GVariant is a signed 16 bit integer.
2159 * @G_VARIANT_CLASS_UINT16: The #GVariant is an unsigned 16 bit integer.
2160 * @G_VARIANT_CLASS_INT32: The #GVariant is a signed 32 bit integer.
2161 * @G_VARIANT_CLASS_UINT32: The #GVariant is an unsigned 32 bit integer.
2162 * @G_VARIANT_CLASS_INT64: The #GVariant is a signed 64 bit integer.
2163 * @G_VARIANT_CLASS_UINT64: The #GVariant is an unsigned 64 bit integer.
2164 * @G_VARIANT_CLASS_HANDLE: The #GVariant is a file handle index.
2165 * @G_VARIANT_CLASS_DOUBLE: The #GVariant is a double precision floating
2166 * point value.
2167 * @G_VARIANT_CLASS_STRING: The #GVariant is a normal string.
2168 * @G_VARIANT_CLASS_OBJECT_PATH: The #GVariant is a D-Bus object path
2169 * string.
2170 * @G_VARIANT_CLASS_SIGNATURE: The #GVariant is a D-Bus signature string.
2171 * @G_VARIANT_CLASS_VARIANT: The #GVariant is a variant.
2172 * @G_VARIANT_CLASS_MAYBE: The #GVariant is a maybe-typed value.
2173 * @G_VARIANT_CLASS_ARRAY: The #GVariant is an array.
2174 * @G_VARIANT_CLASS_TUPLE: The #GVariant is a tuple.
2175 * @G_VARIANT_CLASS_DICT_ENTRY: The #GVariant is a dictionary entry.
2176 *
2177 * The range of possible top-level types of #GVariant instances.
2178 *
2179 * Since: 2.24
2180 **/
2181 GVariantClass
g_variant_classify(GVariant * value)2182 g_variant_classify (GVariant *value)
2183 {
2184 g_return_val_if_fail (value != NULL, 0);
2185
2186 return *g_variant_get_type_string (value);
2187 }
2188
2189 /* Pretty printer {{{1 */
2190 /* This function is not introspectable because if @string is NULL,
2191 @returns is (transfer full), otherwise it is (transfer none), which
2192 is not supported by GObjectIntrospection */
2193 /**
2194 * g_variant_print_string: (skip)
2195 * @value: a #GVariant
2196 * @string: (nullable) (default NULL): a #GString, or %NULL
2197 * @type_annotate: %TRUE if type information should be included in
2198 * the output
2199 *
2200 * Behaves as g_variant_print(), but operates on a #GString.
2201 *
2202 * If @string is non-%NULL then it is appended to and returned. Else,
2203 * a new empty #GString is allocated and it is returned.
2204 *
2205 * Returns: a #GString containing the string
2206 *
2207 * Since: 2.24
2208 **/
2209 GString *
g_variant_print_string(GVariant * value,GString * string,gboolean type_annotate)2210 g_variant_print_string (GVariant *value,
2211 GString *string,
2212 gboolean type_annotate)
2213 {
2214 if G_UNLIKELY (string == NULL)
2215 string = g_string_new (NULL);
2216
2217 switch (g_variant_classify (value))
2218 {
2219 case G_VARIANT_CLASS_MAYBE:
2220 if (type_annotate)
2221 g_string_append_printf (string, "@%s ",
2222 g_variant_get_type_string (value));
2223
2224 if (g_variant_n_children (value))
2225 {
2226 gchar *printed_child;
2227 GVariant *element;
2228
2229 /* Nested maybes:
2230 *
2231 * Consider the case of the type "mmi". In this case we could
2232 * write "just just 4", but "4" alone is totally unambiguous,
2233 * so we try to drop "just" where possible.
2234 *
2235 * We have to be careful not to always drop "just", though,
2236 * since "nothing" needs to be distinguishable from "just
2237 * nothing". The case where we need to ensure we keep the
2238 * "just" is actually exactly the case where we have a nested
2239 * Nothing.
2240 *
2241 * Instead of searching for that nested Nothing, we just print
2242 * the contained value into a separate string and see if we
2243 * end up with "nothing" at the end of it. If so, we need to
2244 * add "just" at our level.
2245 */
2246 element = g_variant_get_child_value (value, 0);
2247 printed_child = g_variant_print (element, FALSE);
2248 g_variant_unref (element);
2249
2250 if (g_str_has_suffix (printed_child, "nothing"))
2251 g_string_append (string, "just ");
2252 g_string_append (string, printed_child);
2253 g_free (printed_child);
2254 }
2255 else
2256 g_string_append (string, "nothing");
2257
2258 break;
2259
2260 case G_VARIANT_CLASS_ARRAY:
2261 /* it's an array so the first character of the type string is 'a'
2262 *
2263 * if the first two characters are 'ay' then it's a bytestring.
2264 * under certain conditions we print those as strings.
2265 */
2266 if (g_variant_get_type_string (value)[1] == 'y')
2267 {
2268 const gchar *str;
2269 gsize size;
2270 gsize i;
2271
2272 /* first determine if it is a byte string.
2273 * that's when there's a single nul character: at the end.
2274 */
2275 str = g_variant_get_data (value);
2276 size = g_variant_get_size (value);
2277
2278 for (i = 0; i < size; i++)
2279 if (str[i] == '\0')
2280 break;
2281
2282 /* first nul byte is the last byte -> it's a byte string. */
2283 if (i == size - 1)
2284 {
2285 gchar *escaped = g_strescape (str, NULL);
2286
2287 /* use double quotes only if a ' is in the string */
2288 if (strchr (str, '\''))
2289 g_string_append_printf (string, "b\"%s\"", escaped);
2290 else
2291 g_string_append_printf (string, "b'%s'", escaped);
2292
2293 g_free (escaped);
2294 break;
2295 }
2296
2297 else
2298 {
2299 /* fall through and handle normally... */
2300 }
2301 }
2302
2303 /*
2304 * if the first two characters are 'a{' then it's an array of
2305 * dictionary entries (ie: a dictionary) so we print that
2306 * differently.
2307 */
2308 if (g_variant_get_type_string (value)[1] == '{')
2309 /* dictionary */
2310 {
2311 const gchar *comma = "";
2312 gsize n, i;
2313
2314 if ((n = g_variant_n_children (value)) == 0)
2315 {
2316 if (type_annotate)
2317 g_string_append_printf (string, "@%s ",
2318 g_variant_get_type_string (value));
2319 g_string_append (string, "{}");
2320 break;
2321 }
2322
2323 g_string_append_c (string, '{');
2324 for (i = 0; i < n; i++)
2325 {
2326 GVariant *entry, *key, *val;
2327
2328 g_string_append (string, comma);
2329 comma = ", ";
2330
2331 entry = g_variant_get_child_value (value, i);
2332 key = g_variant_get_child_value (entry, 0);
2333 val = g_variant_get_child_value (entry, 1);
2334 g_variant_unref (entry);
2335
2336 g_variant_print_string (key, string, type_annotate);
2337 g_variant_unref (key);
2338 g_string_append (string, ": ");
2339 g_variant_print_string (val, string, type_annotate);
2340 g_variant_unref (val);
2341 type_annotate = FALSE;
2342 }
2343 g_string_append_c (string, '}');
2344 }
2345 else
2346 /* normal (non-dictionary) array */
2347 {
2348 const gchar *comma = "";
2349 gsize n, i;
2350
2351 if ((n = g_variant_n_children (value)) == 0)
2352 {
2353 if (type_annotate)
2354 g_string_append_printf (string, "@%s ",
2355 g_variant_get_type_string (value));
2356 g_string_append (string, "[]");
2357 break;
2358 }
2359
2360 g_string_append_c (string, '[');
2361 for (i = 0; i < n; i++)
2362 {
2363 GVariant *element;
2364
2365 g_string_append (string, comma);
2366 comma = ", ";
2367
2368 element = g_variant_get_child_value (value, i);
2369
2370 g_variant_print_string (element, string, type_annotate);
2371 g_variant_unref (element);
2372 type_annotate = FALSE;
2373 }
2374 g_string_append_c (string, ']');
2375 }
2376
2377 break;
2378
2379 case G_VARIANT_CLASS_TUPLE:
2380 {
2381 gsize n, i;
2382
2383 n = g_variant_n_children (value);
2384
2385 g_string_append_c (string, '(');
2386 for (i = 0; i < n; i++)
2387 {
2388 GVariant *element;
2389
2390 element = g_variant_get_child_value (value, i);
2391 g_variant_print_string (element, string, type_annotate);
2392 g_string_append (string, ", ");
2393 g_variant_unref (element);
2394 }
2395
2396 /* for >1 item: remove final ", "
2397 * for 1 item: remove final " ", but leave the ","
2398 * for 0 items: there is only "(", so remove nothing
2399 */
2400 g_string_truncate (string, string->len - (n > 0) - (n > 1));
2401 g_string_append_c (string, ')');
2402 }
2403 break;
2404
2405 case G_VARIANT_CLASS_DICT_ENTRY:
2406 {
2407 GVariant *element;
2408
2409 g_string_append_c (string, '{');
2410
2411 element = g_variant_get_child_value (value, 0);
2412 g_variant_print_string (element, string, type_annotate);
2413 g_variant_unref (element);
2414
2415 g_string_append (string, ", ");
2416
2417 element = g_variant_get_child_value (value, 1);
2418 g_variant_print_string (element, string, type_annotate);
2419 g_variant_unref (element);
2420
2421 g_string_append_c (string, '}');
2422 }
2423 break;
2424
2425 case G_VARIANT_CLASS_VARIANT:
2426 {
2427 GVariant *child = g_variant_get_variant (value);
2428
2429 /* Always annotate types in nested variants, because they are
2430 * (by nature) of variable type.
2431 */
2432 g_string_append_c (string, '<');
2433 g_variant_print_string (child, string, TRUE);
2434 g_string_append_c (string, '>');
2435
2436 g_variant_unref (child);
2437 }
2438 break;
2439
2440 case G_VARIANT_CLASS_BOOLEAN:
2441 if (g_variant_get_boolean (value))
2442 g_string_append (string, "true");
2443 else
2444 g_string_append (string, "false");
2445 break;
2446
2447 case G_VARIANT_CLASS_STRING:
2448 {
2449 const gchar *str = g_variant_get_string (value, NULL);
2450 gunichar quote = strchr (str, '\'') ? '"' : '\'';
2451
2452 g_string_append_c (string, quote);
2453
2454 while (*str)
2455 {
2456 gunichar c = g_utf8_get_char (str);
2457
2458 if (c == quote || c == '\\')
2459 g_string_append_c (string, '\\');
2460
2461 if (g_unichar_isprint (c))
2462 g_string_append_unichar (string, c);
2463
2464 else
2465 {
2466 g_string_append_c (string, '\\');
2467 if (c < 0x10000)
2468 switch (c)
2469 {
2470 case '\a':
2471 g_string_append_c (string, 'a');
2472 break;
2473
2474 case '\b':
2475 g_string_append_c (string, 'b');
2476 break;
2477
2478 case '\f':
2479 g_string_append_c (string, 'f');
2480 break;
2481
2482 case '\n':
2483 g_string_append_c (string, 'n');
2484 break;
2485
2486 case '\r':
2487 g_string_append_c (string, 'r');
2488 break;
2489
2490 case '\t':
2491 g_string_append_c (string, 't');
2492 break;
2493
2494 case '\v':
2495 g_string_append_c (string, 'v');
2496 break;
2497
2498 default:
2499 g_string_append_printf (string, "u%04x", c);
2500 break;
2501 }
2502 else
2503 g_string_append_printf (string, "U%08x", c);
2504 }
2505
2506 str = g_utf8_next_char (str);
2507 }
2508
2509 g_string_append_c (string, quote);
2510 }
2511 break;
2512
2513 case G_VARIANT_CLASS_BYTE:
2514 if (type_annotate)
2515 g_string_append (string, "byte ");
2516 g_string_append_printf (string, "0x%02x",
2517 g_variant_get_byte (value));
2518 break;
2519
2520 case G_VARIANT_CLASS_INT16:
2521 if (type_annotate)
2522 g_string_append (string, "int16 ");
2523 g_string_append_printf (string, "%"G_GINT16_FORMAT,
2524 g_variant_get_int16 (value));
2525 break;
2526
2527 case G_VARIANT_CLASS_UINT16:
2528 if (type_annotate)
2529 g_string_append (string, "uint16 ");
2530 g_string_append_printf (string, "%"G_GUINT16_FORMAT,
2531 g_variant_get_uint16 (value));
2532 break;
2533
2534 case G_VARIANT_CLASS_INT32:
2535 /* Never annotate this type because it is the default for numbers
2536 * (and this is a *pretty* printer)
2537 */
2538 g_string_append_printf (string, "%"G_GINT32_FORMAT,
2539 g_variant_get_int32 (value));
2540 break;
2541
2542 case G_VARIANT_CLASS_HANDLE:
2543 if (type_annotate)
2544 g_string_append (string, "handle ");
2545 g_string_append_printf (string, "%"G_GINT32_FORMAT,
2546 g_variant_get_handle (value));
2547 break;
2548
2549 case G_VARIANT_CLASS_UINT32:
2550 if (type_annotate)
2551 g_string_append (string, "uint32 ");
2552 g_string_append_printf (string, "%"G_GUINT32_FORMAT,
2553 g_variant_get_uint32 (value));
2554 break;
2555
2556 case G_VARIANT_CLASS_INT64:
2557 if (type_annotate)
2558 g_string_append (string, "int64 ");
2559 g_string_append_printf (string, "%"G_GINT64_FORMAT,
2560 g_variant_get_int64 (value));
2561 break;
2562
2563 case G_VARIANT_CLASS_UINT64:
2564 if (type_annotate)
2565 g_string_append (string, "uint64 ");
2566 g_string_append_printf (string, "%"G_GUINT64_FORMAT,
2567 g_variant_get_uint64 (value));
2568 break;
2569
2570 case G_VARIANT_CLASS_DOUBLE:
2571 {
2572 gchar buffer[100];
2573 gint i;
2574
2575 g_ascii_dtostr (buffer, sizeof buffer, g_variant_get_double (value));
2576
2577 for (i = 0; buffer[i]; i++)
2578 if (buffer[i] == '.' || buffer[i] == 'e' ||
2579 buffer[i] == 'n' || buffer[i] == 'N')
2580 break;
2581
2582 /* if there is no '.' or 'e' in the float then add one */
2583 if (buffer[i] == '\0')
2584 {
2585 buffer[i++] = '.';
2586 buffer[i++] = '0';
2587 buffer[i++] = '\0';
2588 }
2589
2590 g_string_append (string, buffer);
2591 }
2592 break;
2593
2594 case G_VARIANT_CLASS_OBJECT_PATH:
2595 if (type_annotate)
2596 g_string_append (string, "objectpath ");
2597 g_string_append_printf (string, "\'%s\'",
2598 g_variant_get_string (value, NULL));
2599 break;
2600
2601 case G_VARIANT_CLASS_SIGNATURE:
2602 if (type_annotate)
2603 g_string_append (string, "signature ");
2604 g_string_append_printf (string, "\'%s\'",
2605 g_variant_get_string (value, NULL));
2606 break;
2607
2608 default:
2609 g_assert_not_reached ();
2610 }
2611
2612 return string;
2613 }
2614
2615 /**
2616 * g_variant_print:
2617 * @value: a #GVariant
2618 * @type_annotate: %TRUE if type information should be included in
2619 * the output
2620 *
2621 * Pretty-prints @value in the format understood by g_variant_parse().
2622 *
2623 * The format is described [here][gvariant-text].
2624 *
2625 * If @type_annotate is %TRUE, then type information is included in
2626 * the output.
2627 *
2628 * Returns: (transfer full): a newly-allocated string holding the result.
2629 *
2630 * Since: 2.24
2631 */
2632 gchar *
g_variant_print(GVariant * value,gboolean type_annotate)2633 g_variant_print (GVariant *value,
2634 gboolean type_annotate)
2635 {
2636 return g_string_free (g_variant_print_string (value, NULL, type_annotate),
2637 FALSE);
2638 }
2639
2640 /* Hash, Equal, Compare {{{1 */
2641 /**
2642 * g_variant_hash:
2643 * @value: (type GVariant): a basic #GVariant value as a #gconstpointer
2644 *
2645 * Generates a hash value for a #GVariant instance.
2646 *
2647 * The output of this function is guaranteed to be the same for a given
2648 * value only per-process. It may change between different processor
2649 * architectures or even different versions of GLib. Do not use this
2650 * function as a basis for building protocols or file formats.
2651 *
2652 * The type of @value is #gconstpointer only to allow use of this
2653 * function with #GHashTable. @value must be a #GVariant.
2654 *
2655 * Returns: a hash value corresponding to @value
2656 *
2657 * Since: 2.24
2658 **/
2659 guint
g_variant_hash(gconstpointer value_)2660 g_variant_hash (gconstpointer value_)
2661 {
2662 GVariant *value = (GVariant *) value_;
2663
2664 switch (g_variant_classify (value))
2665 {
2666 case G_VARIANT_CLASS_STRING:
2667 case G_VARIANT_CLASS_OBJECT_PATH:
2668 case G_VARIANT_CLASS_SIGNATURE:
2669 return g_str_hash (g_variant_get_string (value, NULL));
2670
2671 case G_VARIANT_CLASS_BOOLEAN:
2672 /* this is a very odd thing to hash... */
2673 return g_variant_get_boolean (value);
2674
2675 case G_VARIANT_CLASS_BYTE:
2676 return g_variant_get_byte (value);
2677
2678 case G_VARIANT_CLASS_INT16:
2679 case G_VARIANT_CLASS_UINT16:
2680 {
2681 const guint16 *ptr;
2682
2683 ptr = g_variant_get_data (value);
2684
2685 if (ptr)
2686 return *ptr;
2687 else
2688 return 0;
2689 }
2690
2691 case G_VARIANT_CLASS_INT32:
2692 case G_VARIANT_CLASS_UINT32:
2693 case G_VARIANT_CLASS_HANDLE:
2694 {
2695 const guint *ptr;
2696
2697 ptr = g_variant_get_data (value);
2698
2699 if (ptr)
2700 return *ptr;
2701 else
2702 return 0;
2703 }
2704
2705 case G_VARIANT_CLASS_INT64:
2706 case G_VARIANT_CLASS_UINT64:
2707 case G_VARIANT_CLASS_DOUBLE:
2708 /* need a separate case for these guys because otherwise
2709 * performance could be quite bad on big endian systems
2710 */
2711 {
2712 const guint *ptr;
2713
2714 ptr = g_variant_get_data (value);
2715
2716 if (ptr)
2717 return ptr[0] + ptr[1];
2718 else
2719 return 0;
2720 }
2721
2722 default:
2723 g_return_val_if_fail (!g_variant_is_container (value), 0);
2724 g_assert_not_reached ();
2725 }
2726 }
2727
2728 /**
2729 * g_variant_equal:
2730 * @one: (type GVariant): a #GVariant instance
2731 * @two: (type GVariant): a #GVariant instance
2732 *
2733 * Checks if @one and @two have the same type and value.
2734 *
2735 * The types of @one and @two are #gconstpointer only to allow use of
2736 * this function with #GHashTable. They must each be a #GVariant.
2737 *
2738 * Returns: %TRUE if @one and @two are equal
2739 *
2740 * Since: 2.24
2741 **/
2742 gboolean
g_variant_equal(gconstpointer one,gconstpointer two)2743 g_variant_equal (gconstpointer one,
2744 gconstpointer two)
2745 {
2746 gboolean equal;
2747
2748 g_return_val_if_fail (one != NULL && two != NULL, FALSE);
2749
2750 if (g_variant_get_type_info ((GVariant *) one) !=
2751 g_variant_get_type_info ((GVariant *) two))
2752 return FALSE;
2753
2754 /* if both values are trusted to be in their canonical serialized form
2755 * then a simple memcmp() of their serialized data will answer the
2756 * question.
2757 *
2758 * if not, then this might generate a false negative (since it is
2759 * possible for two different byte sequences to represent the same
2760 * value). for now we solve this by pretty-printing both values and
2761 * comparing the result.
2762 */
2763 if (g_variant_is_trusted ((GVariant *) one) &&
2764 g_variant_is_trusted ((GVariant *) two))
2765 {
2766 gconstpointer data_one, data_two;
2767 gsize size_one, size_two;
2768
2769 size_one = g_variant_get_size ((GVariant *) one);
2770 size_two = g_variant_get_size ((GVariant *) two);
2771
2772 if (size_one != size_two)
2773 return FALSE;
2774
2775 data_one = g_variant_get_data ((GVariant *) one);
2776 data_two = g_variant_get_data ((GVariant *) two);
2777
2778 if (size_one)
2779 equal = memcmp (data_one, data_two, size_one) == 0;
2780 else
2781 equal = TRUE;
2782 }
2783 else
2784 {
2785 gchar *strone, *strtwo;
2786
2787 strone = g_variant_print ((GVariant *) one, FALSE);
2788 strtwo = g_variant_print ((GVariant *) two, FALSE);
2789 equal = strcmp (strone, strtwo) == 0;
2790 g_free (strone);
2791 g_free (strtwo);
2792 }
2793
2794 return equal;
2795 }
2796
2797 /**
2798 * g_variant_compare:
2799 * @one: (type GVariant): a basic-typed #GVariant instance
2800 * @two: (type GVariant): a #GVariant instance of the same type
2801 *
2802 * Compares @one and @two.
2803 *
2804 * The types of @one and @two are #gconstpointer only to allow use of
2805 * this function with #GTree, #GPtrArray, etc. They must each be a
2806 * #GVariant.
2807 *
2808 * Comparison is only defined for basic types (ie: booleans, numbers,
2809 * strings). For booleans, %FALSE is less than %TRUE. Numbers are
2810 * ordered in the usual way. Strings are in ASCII lexographical order.
2811 *
2812 * It is a programmer error to attempt to compare container values or
2813 * two values that have types that are not exactly equal. For example,
2814 * you cannot compare a 32-bit signed integer with a 32-bit unsigned
2815 * integer. Also note that this function is not particularly
2816 * well-behaved when it comes to comparison of doubles; in particular,
2817 * the handling of incomparable values (ie: NaN) is undefined.
2818 *
2819 * If you only require an equality comparison, g_variant_equal() is more
2820 * general.
2821 *
2822 * Returns: negative value if a < b;
2823 * zero if a = b;
2824 * positive value if a > b.
2825 *
2826 * Since: 2.26
2827 **/
2828 gint
g_variant_compare(gconstpointer one,gconstpointer two)2829 g_variant_compare (gconstpointer one,
2830 gconstpointer two)
2831 {
2832 GVariant *a = (GVariant *) one;
2833 GVariant *b = (GVariant *) two;
2834
2835 g_return_val_if_fail (g_variant_classify (a) == g_variant_classify (b), 0);
2836
2837 switch (g_variant_classify (a))
2838 {
2839 case G_VARIANT_CLASS_BOOLEAN:
2840 return g_variant_get_boolean (a) -
2841 g_variant_get_boolean (b);
2842
2843 case G_VARIANT_CLASS_BYTE:
2844 return ((gint) g_variant_get_byte (a)) -
2845 ((gint) g_variant_get_byte (b));
2846
2847 case G_VARIANT_CLASS_INT16:
2848 return ((gint) g_variant_get_int16 (a)) -
2849 ((gint) g_variant_get_int16 (b));
2850
2851 case G_VARIANT_CLASS_UINT16:
2852 return ((gint) g_variant_get_uint16 (a)) -
2853 ((gint) g_variant_get_uint16 (b));
2854
2855 case G_VARIANT_CLASS_INT32:
2856 {
2857 gint32 a_val = g_variant_get_int32 (a);
2858 gint32 b_val = g_variant_get_int32 (b);
2859
2860 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2861 }
2862
2863 case G_VARIANT_CLASS_UINT32:
2864 {
2865 guint32 a_val = g_variant_get_uint32 (a);
2866 guint32 b_val = g_variant_get_uint32 (b);
2867
2868 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2869 }
2870
2871 case G_VARIANT_CLASS_INT64:
2872 {
2873 gint64 a_val = g_variant_get_int64 (a);
2874 gint64 b_val = g_variant_get_int64 (b);
2875
2876 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2877 }
2878
2879 case G_VARIANT_CLASS_UINT64:
2880 {
2881 guint64 a_val = g_variant_get_uint64 (a);
2882 guint64 b_val = g_variant_get_uint64 (b);
2883
2884 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2885 }
2886
2887 case G_VARIANT_CLASS_DOUBLE:
2888 {
2889 gdouble a_val = g_variant_get_double (a);
2890 gdouble b_val = g_variant_get_double (b);
2891
2892 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2893 }
2894
2895 case G_VARIANT_CLASS_STRING:
2896 case G_VARIANT_CLASS_OBJECT_PATH:
2897 case G_VARIANT_CLASS_SIGNATURE:
2898 return strcmp (g_variant_get_string (a, NULL),
2899 g_variant_get_string (b, NULL));
2900
2901 default:
2902 g_return_val_if_fail (!g_variant_is_container (a), 0);
2903 g_assert_not_reached ();
2904 }
2905 }
2906
2907 /* GVariantIter {{{1 */
2908 /**
2909 * GVariantIter: (skip)
2910 *
2911 * #GVariantIter is an opaque data structure and can only be accessed
2912 * using the following functions.
2913 **/
2914 struct stack_iter
2915 {
2916 GVariant *value;
2917 gssize n, i;
2918
2919 const gchar *loop_format;
2920
2921 gsize padding[3];
2922 gsize magic;
2923 };
2924
2925 G_STATIC_ASSERT (sizeof (struct stack_iter) <= sizeof (GVariantIter));
2926
2927 struct heap_iter
2928 {
2929 struct stack_iter iter;
2930
2931 GVariant *value_ref;
2932 gsize magic;
2933 };
2934
2935 #define GVSI(i) ((struct stack_iter *) (i))
2936 #define GVHI(i) ((struct heap_iter *) (i))
2937 #define GVSI_MAGIC ((gsize) 3579507750u)
2938 #define GVHI_MAGIC ((gsize) 1450270775u)
2939 #define is_valid_iter(i) (i != NULL && \
2940 GVSI(i)->magic == GVSI_MAGIC)
2941 #define is_valid_heap_iter(i) (is_valid_iter(i) && \
2942 GVHI(i)->magic == GVHI_MAGIC)
2943
2944 /**
2945 * g_variant_iter_new:
2946 * @value: a container #GVariant
2947 *
2948 * Creates a heap-allocated #GVariantIter for iterating over the items
2949 * in @value.
2950 *
2951 * Use g_variant_iter_free() to free the return value when you no longer
2952 * need it.
2953 *
2954 * A reference is taken to @value and will be released only when
2955 * g_variant_iter_free() is called.
2956 *
2957 * Returns: (transfer full): a new heap-allocated #GVariantIter
2958 *
2959 * Since: 2.24
2960 **/
2961 GVariantIter *
g_variant_iter_new(GVariant * value)2962 g_variant_iter_new (GVariant *value)
2963 {
2964 GVariantIter *iter;
2965
2966 iter = (GVariantIter *) g_slice_new (struct heap_iter);
2967 GVHI(iter)->value_ref = g_variant_ref (value);
2968 GVHI(iter)->magic = GVHI_MAGIC;
2969
2970 g_variant_iter_init (iter, value);
2971
2972 return iter;
2973 }
2974
2975 /**
2976 * g_variant_iter_init: (skip)
2977 * @iter: a pointer to a #GVariantIter
2978 * @value: a container #GVariant
2979 *
2980 * Initialises (without allocating) a #GVariantIter. @iter may be
2981 * completely uninitialised prior to this call; its old value is
2982 * ignored.
2983 *
2984 * The iterator remains valid for as long as @value exists, and need not
2985 * be freed in any way.
2986 *
2987 * Returns: the number of items in @value
2988 *
2989 * Since: 2.24
2990 **/
2991 gsize
g_variant_iter_init(GVariantIter * iter,GVariant * value)2992 g_variant_iter_init (GVariantIter *iter,
2993 GVariant *value)
2994 {
2995 GVSI(iter)->magic = GVSI_MAGIC;
2996 GVSI(iter)->value = value;
2997 GVSI(iter)->n = g_variant_n_children (value);
2998 GVSI(iter)->i = -1;
2999 GVSI(iter)->loop_format = NULL;
3000
3001 return GVSI(iter)->n;
3002 }
3003
3004 /**
3005 * g_variant_iter_copy:
3006 * @iter: a #GVariantIter
3007 *
3008 * Creates a new heap-allocated #GVariantIter to iterate over the
3009 * container that was being iterated over by @iter. Iteration begins on
3010 * the new iterator from the current position of the old iterator but
3011 * the two copies are independent past that point.
3012 *
3013 * Use g_variant_iter_free() to free the return value when you no longer
3014 * need it.
3015 *
3016 * A reference is taken to the container that @iter is iterating over
3017 * and will be related only when g_variant_iter_free() is called.
3018 *
3019 * Returns: (transfer full): a new heap-allocated #GVariantIter
3020 *
3021 * Since: 2.24
3022 **/
3023 GVariantIter *
g_variant_iter_copy(GVariantIter * iter)3024 g_variant_iter_copy (GVariantIter *iter)
3025 {
3026 GVariantIter *copy;
3027
3028 g_return_val_if_fail (is_valid_iter (iter), 0);
3029
3030 copy = g_variant_iter_new (GVSI(iter)->value);
3031 GVSI(copy)->i = GVSI(iter)->i;
3032
3033 return copy;
3034 }
3035
3036 /**
3037 * g_variant_iter_n_children:
3038 * @iter: a #GVariantIter
3039 *
3040 * Queries the number of child items in the container that we are
3041 * iterating over. This is the total number of items -- not the number
3042 * of items remaining.
3043 *
3044 * This function might be useful for preallocation of arrays.
3045 *
3046 * Returns: the number of children in the container
3047 *
3048 * Since: 2.24
3049 **/
3050 gsize
g_variant_iter_n_children(GVariantIter * iter)3051 g_variant_iter_n_children (GVariantIter *iter)
3052 {
3053 g_return_val_if_fail (is_valid_iter (iter), 0);
3054
3055 return GVSI(iter)->n;
3056 }
3057
3058 /**
3059 * g_variant_iter_free:
3060 * @iter: (transfer full): a heap-allocated #GVariantIter
3061 *
3062 * Frees a heap-allocated #GVariantIter. Only call this function on
3063 * iterators that were returned by g_variant_iter_new() or
3064 * g_variant_iter_copy().
3065 *
3066 * Since: 2.24
3067 **/
3068 void
g_variant_iter_free(GVariantIter * iter)3069 g_variant_iter_free (GVariantIter *iter)
3070 {
3071 g_return_if_fail (is_valid_heap_iter (iter));
3072
3073 g_variant_unref (GVHI(iter)->value_ref);
3074 GVHI(iter)->magic = 0;
3075
3076 g_slice_free (struct heap_iter, GVHI(iter));
3077 }
3078
3079 /**
3080 * g_variant_iter_next_value:
3081 * @iter: a #GVariantIter
3082 *
3083 * Gets the next item in the container. If no more items remain then
3084 * %NULL is returned.
3085 *
3086 * Use g_variant_unref() to drop your reference on the return value when
3087 * you no longer need it.
3088 *
3089 * Here is an example for iterating with g_variant_iter_next_value():
3090 * |[<!-- language="C" -->
3091 * // recursively iterate a container
3092 * void
3093 * iterate_container_recursive (GVariant *container)
3094 * {
3095 * GVariantIter iter;
3096 * GVariant *child;
3097 *
3098 * g_variant_iter_init (&iter, container);
3099 * while ((child = g_variant_iter_next_value (&iter)))
3100 * {
3101 * g_print ("type '%s'\n", g_variant_get_type_string (child));
3102 *
3103 * if (g_variant_is_container (child))
3104 * iterate_container_recursive (child);
3105 *
3106 * g_variant_unref (child);
3107 * }
3108 * }
3109 * ]|
3110 *
3111 * Returns: (nullable) (transfer full): a #GVariant, or %NULL
3112 *
3113 * Since: 2.24
3114 **/
3115 GVariant *
g_variant_iter_next_value(GVariantIter * iter)3116 g_variant_iter_next_value (GVariantIter *iter)
3117 {
3118 g_return_val_if_fail (is_valid_iter (iter), FALSE);
3119
3120 if G_UNLIKELY (GVSI(iter)->i >= GVSI(iter)->n)
3121 {
3122 g_critical ("g_variant_iter_next_value: must not be called again "
3123 "after NULL has already been returned.");
3124 return NULL;
3125 }
3126
3127 GVSI(iter)->i++;
3128
3129 if (GVSI(iter)->i < GVSI(iter)->n)
3130 return g_variant_get_child_value (GVSI(iter)->value, GVSI(iter)->i);
3131
3132 return NULL;
3133 }
3134
3135 /* GVariantBuilder {{{1 */
3136 /**
3137 * GVariantBuilder:
3138 *
3139 * A utility type for constructing container-type #GVariant instances.
3140 *
3141 * This is an opaque structure and may only be accessed using the
3142 * following functions.
3143 *
3144 * #GVariantBuilder is not threadsafe in any way. Do not attempt to
3145 * access it from more than one thread.
3146 **/
3147
3148 struct stack_builder
3149 {
3150 GVariantBuilder *parent;
3151 GVariantType *type;
3152
3153 /* type constraint explicitly specified by 'type'.
3154 * for tuple types, this moves along as we add more items.
3155 */
3156 const GVariantType *expected_type;
3157
3158 /* type constraint implied by previous array item.
3159 */
3160 const GVariantType *prev_item_type;
3161
3162 /* constraints on the number of children. max = -1 for unlimited. */
3163 gsize min_items;
3164 gsize max_items;
3165
3166 /* dynamically-growing pointer array */
3167 GVariant **children;
3168 gsize allocated_children;
3169 gsize offset;
3170
3171 /* set to '1' if all items in the container will have the same type
3172 * (ie: maybe, array, variant) '0' if not (ie: tuple, dict entry)
3173 */
3174 guint uniform_item_types : 1;
3175
3176 /* set to '1' initially and changed to '0' if an untrusted value is
3177 * added
3178 */
3179 guint trusted : 1;
3180
3181 gsize magic;
3182 };
3183
3184 G_STATIC_ASSERT (sizeof (struct stack_builder) <= sizeof (GVariantBuilder));
3185
3186 struct heap_builder
3187 {
3188 GVariantBuilder builder;
3189 gsize magic;
3190
3191 gint ref_count;
3192 };
3193
3194 #define GVSB(b) ((struct stack_builder *) (b))
3195 #define GVHB(b) ((struct heap_builder *) (b))
3196 #define GVSB_MAGIC ((gsize) 1033660112u)
3197 #define GVSB_MAGIC_PARTIAL ((gsize) 2942751021u)
3198 #define GVHB_MAGIC ((gsize) 3087242682u)
3199 #define is_valid_builder(b) (GVSB(b)->magic == GVSB_MAGIC)
3200 #define is_valid_heap_builder(b) (GVHB(b)->magic == GVHB_MAGIC)
3201
3202 /* Just to make sure that by adding a union to GVariantBuilder, we
3203 * didn't accidentally change ABI. */
3204 G_STATIC_ASSERT (sizeof (GVariantBuilder) == sizeof (gsize[16]));
3205
3206 static gboolean
ensure_valid_builder(GVariantBuilder * builder)3207 ensure_valid_builder (GVariantBuilder *builder)
3208 {
3209 if (builder == NULL)
3210 return FALSE;
3211 else if (is_valid_builder (builder))
3212 return TRUE;
3213 if (builder->u.s.partial_magic == GVSB_MAGIC_PARTIAL)
3214 {
3215 static GVariantBuilder cleared_builder;
3216
3217 /* Make sure that only first two fields were set and the rest is
3218 * zeroed to avoid messing up the builder that had parent
3219 * address equal to GVSB_MAGIC_PARTIAL. */
3220 if (memcmp (cleared_builder.u.s.y, builder->u.s.y, sizeof cleared_builder.u.s.y))
3221 return FALSE;
3222
3223 g_variant_builder_init (builder, builder->u.s.type);
3224 }
3225 return is_valid_builder (builder);
3226 }
3227
3228 /**
3229 * g_variant_builder_new:
3230 * @type: a container type
3231 *
3232 * Allocates and initialises a new #GVariantBuilder.
3233 *
3234 * You should call g_variant_builder_unref() on the return value when it
3235 * is no longer needed. The memory will not be automatically freed by
3236 * any other call.
3237 *
3238 * In most cases it is easier to place a #GVariantBuilder directly on
3239 * the stack of the calling function and initialise it with
3240 * g_variant_builder_init().
3241 *
3242 * Returns: (transfer full): a #GVariantBuilder
3243 *
3244 * Since: 2.24
3245 **/
3246 GVariantBuilder *
g_variant_builder_new(const GVariantType * type)3247 g_variant_builder_new (const GVariantType *type)
3248 {
3249 GVariantBuilder *builder;
3250
3251 builder = (GVariantBuilder *) g_slice_new (struct heap_builder);
3252 g_variant_builder_init (builder, type);
3253 GVHB(builder)->magic = GVHB_MAGIC;
3254 GVHB(builder)->ref_count = 1;
3255
3256 return builder;
3257 }
3258
3259 /**
3260 * g_variant_builder_unref:
3261 * @builder: (transfer full): a #GVariantBuilder allocated by g_variant_builder_new()
3262 *
3263 * Decreases the reference count on @builder.
3264 *
3265 * In the event that there are no more references, releases all memory
3266 * associated with the #GVariantBuilder.
3267 *
3268 * Don't call this on stack-allocated #GVariantBuilder instances or bad
3269 * things will happen.
3270 *
3271 * Since: 2.24
3272 **/
3273 void
g_variant_builder_unref(GVariantBuilder * builder)3274 g_variant_builder_unref (GVariantBuilder *builder)
3275 {
3276 g_return_if_fail (is_valid_heap_builder (builder));
3277
3278 if (--GVHB(builder)->ref_count)
3279 return;
3280
3281 g_variant_builder_clear (builder);
3282 GVHB(builder)->magic = 0;
3283
3284 g_slice_free (struct heap_builder, GVHB(builder));
3285 }
3286
3287 /**
3288 * g_variant_builder_ref:
3289 * @builder: a #GVariantBuilder allocated by g_variant_builder_new()
3290 *
3291 * Increases the reference count on @builder.
3292 *
3293 * Don't call this on stack-allocated #GVariantBuilder instances or bad
3294 * things will happen.
3295 *
3296 * Returns: (transfer full): a new reference to @builder
3297 *
3298 * Since: 2.24
3299 **/
3300 GVariantBuilder *
g_variant_builder_ref(GVariantBuilder * builder)3301 g_variant_builder_ref (GVariantBuilder *builder)
3302 {
3303 g_return_val_if_fail (is_valid_heap_builder (builder), NULL);
3304
3305 GVHB(builder)->ref_count++;
3306
3307 return builder;
3308 }
3309
3310 /**
3311 * g_variant_builder_clear: (skip)
3312 * @builder: a #GVariantBuilder
3313 *
3314 * Releases all memory associated with a #GVariantBuilder without
3315 * freeing the #GVariantBuilder structure itself.
3316 *
3317 * It typically only makes sense to do this on a stack-allocated
3318 * #GVariantBuilder if you want to abort building the value part-way
3319 * through. This function need not be called if you call
3320 * g_variant_builder_end() and it also doesn't need to be called on
3321 * builders allocated with g_variant_builder_new() (see
3322 * g_variant_builder_unref() for that).
3323 *
3324 * This function leaves the #GVariantBuilder structure set to all-zeros.
3325 * It is valid to call this function on either an initialised
3326 * #GVariantBuilder or one that is set to all-zeros but it is not valid
3327 * to call this function on uninitialised memory.
3328 *
3329 * Since: 2.24
3330 **/
3331 void
g_variant_builder_clear(GVariantBuilder * builder)3332 g_variant_builder_clear (GVariantBuilder *builder)
3333 {
3334 gsize i;
3335
3336 if (GVSB(builder)->magic == 0)
3337 /* all-zeros or partial case */
3338 return;
3339
3340 g_return_if_fail (ensure_valid_builder (builder));
3341
3342 g_variant_type_free (GVSB(builder)->type);
3343
3344 for (i = 0; i < GVSB(builder)->offset; i++)
3345 g_variant_unref (GVSB(builder)->children[i]);
3346
3347 g_free (GVSB(builder)->children);
3348
3349 if (GVSB(builder)->parent)
3350 {
3351 g_variant_builder_clear (GVSB(builder)->parent);
3352 g_slice_free (GVariantBuilder, GVSB(builder)->parent);
3353 }
3354
3355 memset (builder, 0, sizeof (GVariantBuilder));
3356 }
3357
3358 /**
3359 * g_variant_builder_init: (skip)
3360 * @builder: a #GVariantBuilder
3361 * @type: a container type
3362 *
3363 * Initialises a #GVariantBuilder structure.
3364 *
3365 * @type must be non-%NULL. It specifies the type of container to
3366 * construct. It can be an indefinite type such as
3367 * %G_VARIANT_TYPE_ARRAY or a definite type such as "as" or "(ii)".
3368 * Maybe, array, tuple, dictionary entry and variant-typed values may be
3369 * constructed.
3370 *
3371 * After the builder is initialised, values are added using
3372 * g_variant_builder_add_value() or g_variant_builder_add().
3373 *
3374 * After all the child values are added, g_variant_builder_end() frees
3375 * the memory associated with the builder and returns the #GVariant that
3376 * was created.
3377 *
3378 * This function completely ignores the previous contents of @builder.
3379 * On one hand this means that it is valid to pass in completely
3380 * uninitialised memory. On the other hand, this means that if you are
3381 * initialising over top of an existing #GVariantBuilder you need to
3382 * first call g_variant_builder_clear() in order to avoid leaking
3383 * memory.
3384 *
3385 * You must not call g_variant_builder_ref() or
3386 * g_variant_builder_unref() on a #GVariantBuilder that was initialised
3387 * with this function. If you ever pass a reference to a
3388 * #GVariantBuilder outside of the control of your own code then you
3389 * should assume that the person receiving that reference may try to use
3390 * reference counting; you should use g_variant_builder_new() instead of
3391 * this function.
3392 *
3393 * Since: 2.24
3394 **/
3395 void
g_variant_builder_init(GVariantBuilder * builder,const GVariantType * type)3396 g_variant_builder_init (GVariantBuilder *builder,
3397 const GVariantType *type)
3398 {
3399 g_return_if_fail (type != NULL);
3400 g_return_if_fail (g_variant_type_is_container (type));
3401
3402 memset (builder, 0, sizeof (GVariantBuilder));
3403
3404 GVSB(builder)->type = g_variant_type_copy (type);
3405 GVSB(builder)->magic = GVSB_MAGIC;
3406 GVSB(builder)->trusted = TRUE;
3407
3408 switch (*(const gchar *) type)
3409 {
3410 case G_VARIANT_CLASS_VARIANT:
3411 GVSB(builder)->uniform_item_types = TRUE;
3412 GVSB(builder)->allocated_children = 1;
3413 GVSB(builder)->expected_type = NULL;
3414 GVSB(builder)->min_items = 1;
3415 GVSB(builder)->max_items = 1;
3416 break;
3417
3418 case G_VARIANT_CLASS_ARRAY:
3419 GVSB(builder)->uniform_item_types = TRUE;
3420 GVSB(builder)->allocated_children = 8;
3421 GVSB(builder)->expected_type =
3422 g_variant_type_element (GVSB(builder)->type);
3423 GVSB(builder)->min_items = 0;
3424 GVSB(builder)->max_items = -1;
3425 break;
3426
3427 case G_VARIANT_CLASS_MAYBE:
3428 GVSB(builder)->uniform_item_types = TRUE;
3429 GVSB(builder)->allocated_children = 1;
3430 GVSB(builder)->expected_type =
3431 g_variant_type_element (GVSB(builder)->type);
3432 GVSB(builder)->min_items = 0;
3433 GVSB(builder)->max_items = 1;
3434 break;
3435
3436 case G_VARIANT_CLASS_DICT_ENTRY:
3437 GVSB(builder)->uniform_item_types = FALSE;
3438 GVSB(builder)->allocated_children = 2;
3439 GVSB(builder)->expected_type =
3440 g_variant_type_key (GVSB(builder)->type);
3441 GVSB(builder)->min_items = 2;
3442 GVSB(builder)->max_items = 2;
3443 break;
3444
3445 case 'r': /* G_VARIANT_TYPE_TUPLE was given */
3446 GVSB(builder)->uniform_item_types = FALSE;
3447 GVSB(builder)->allocated_children = 8;
3448 GVSB(builder)->expected_type = NULL;
3449 GVSB(builder)->min_items = 0;
3450 GVSB(builder)->max_items = -1;
3451 break;
3452
3453 case G_VARIANT_CLASS_TUPLE: /* a definite tuple type was given */
3454 GVSB(builder)->allocated_children = g_variant_type_n_items (type);
3455 GVSB(builder)->expected_type =
3456 g_variant_type_first (GVSB(builder)->type);
3457 GVSB(builder)->min_items = GVSB(builder)->allocated_children;
3458 GVSB(builder)->max_items = GVSB(builder)->allocated_children;
3459 GVSB(builder)->uniform_item_types = FALSE;
3460 break;
3461
3462 default:
3463 g_assert_not_reached ();
3464 }
3465
3466 GVSB(builder)->children = g_new (GVariant *,
3467 GVSB(builder)->allocated_children);
3468 }
3469
3470 static void
g_variant_builder_make_room(struct stack_builder * builder)3471 g_variant_builder_make_room (struct stack_builder *builder)
3472 {
3473 if (builder->offset == builder->allocated_children)
3474 {
3475 builder->allocated_children *= 2;
3476 builder->children = g_renew (GVariant *, builder->children,
3477 builder->allocated_children);
3478 }
3479 }
3480
3481 /**
3482 * g_variant_builder_add_value:
3483 * @builder: a #GVariantBuilder
3484 * @value: a #GVariant
3485 *
3486 * Adds @value to @builder.
3487 *
3488 * It is an error to call this function in any way that would create an
3489 * inconsistent value to be constructed. Some examples of this are
3490 * putting different types of items into an array, putting the wrong
3491 * types or number of items in a tuple, putting more than one value into
3492 * a variant, etc.
3493 *
3494 * If @value is a floating reference (see g_variant_ref_sink()),
3495 * the @builder instance takes ownership of @value.
3496 *
3497 * Since: 2.24
3498 **/
3499 void
g_variant_builder_add_value(GVariantBuilder * builder,GVariant * value)3500 g_variant_builder_add_value (GVariantBuilder *builder,
3501 GVariant *value)
3502 {
3503 g_return_if_fail (ensure_valid_builder (builder));
3504 g_return_if_fail (GVSB(builder)->offset < GVSB(builder)->max_items);
3505 g_return_if_fail (!GVSB(builder)->expected_type ||
3506 g_variant_is_of_type (value,
3507 GVSB(builder)->expected_type));
3508 g_return_if_fail (!GVSB(builder)->prev_item_type ||
3509 g_variant_is_of_type (value,
3510 GVSB(builder)->prev_item_type));
3511
3512 GVSB(builder)->trusted &= g_variant_is_trusted (value);
3513
3514 if (!GVSB(builder)->uniform_item_types)
3515 {
3516 /* advance our expected type pointers */
3517 if (GVSB(builder)->expected_type)
3518 GVSB(builder)->expected_type =
3519 g_variant_type_next (GVSB(builder)->expected_type);
3520
3521 if (GVSB(builder)->prev_item_type)
3522 GVSB(builder)->prev_item_type =
3523 g_variant_type_next (GVSB(builder)->prev_item_type);
3524 }
3525 else
3526 GVSB(builder)->prev_item_type = g_variant_get_type (value);
3527
3528 g_variant_builder_make_room (GVSB(builder));
3529
3530 GVSB(builder)->children[GVSB(builder)->offset++] =
3531 g_variant_ref_sink (value);
3532 }
3533
3534 /**
3535 * g_variant_builder_open:
3536 * @builder: a #GVariantBuilder
3537 * @type: the #GVariantType of the container
3538 *
3539 * Opens a subcontainer inside the given @builder. When done adding
3540 * items to the subcontainer, g_variant_builder_close() must be called. @type
3541 * is the type of the container: so to build a tuple of several values, @type
3542 * must include the tuple itself.
3543 *
3544 * It is an error to call this function in any way that would cause an
3545 * inconsistent value to be constructed (ie: adding too many values or
3546 * a value of an incorrect type).
3547 *
3548 * Example of building a nested variant:
3549 * |[<!-- language="C" -->
3550 * GVariantBuilder builder;
3551 * guint32 some_number = get_number ();
3552 * g_autoptr (GHashTable) some_dict = get_dict ();
3553 * GHashTableIter iter;
3554 * const gchar *key;
3555 * const GVariant *value;
3556 * g_autoptr (GVariant) output = NULL;
3557 *
3558 * g_variant_builder_init (&builder, G_VARIANT_TYPE ("(ua{sv})"));
3559 * g_variant_builder_add (&builder, "u", some_number);
3560 * g_variant_builder_open (&builder, G_VARIANT_TYPE ("a{sv}"));
3561 *
3562 * g_hash_table_iter_init (&iter, some_dict);
3563 * while (g_hash_table_iter_next (&iter, (gpointer *) &key, (gpointer *) &value))
3564 * {
3565 * g_variant_builder_open (&builder, G_VARIANT_TYPE ("{sv}"));
3566 * g_variant_builder_add (&builder, "s", key);
3567 * g_variant_builder_add (&builder, "v", value);
3568 * g_variant_builder_close (&builder);
3569 * }
3570 *
3571 * g_variant_builder_close (&builder);
3572 *
3573 * output = g_variant_builder_end (&builder);
3574 * ]|
3575 *
3576 * Since: 2.24
3577 **/
3578 void
g_variant_builder_open(GVariantBuilder * builder,const GVariantType * type)3579 g_variant_builder_open (GVariantBuilder *builder,
3580 const GVariantType *type)
3581 {
3582 GVariantBuilder *parent;
3583
3584 g_return_if_fail (ensure_valid_builder (builder));
3585 g_return_if_fail (GVSB(builder)->offset < GVSB(builder)->max_items);
3586 g_return_if_fail (!GVSB(builder)->expected_type ||
3587 g_variant_type_is_subtype_of (type,
3588 GVSB(builder)->expected_type));
3589 g_return_if_fail (!GVSB(builder)->prev_item_type ||
3590 g_variant_type_is_subtype_of (GVSB(builder)->prev_item_type,
3591 type));
3592
3593 parent = g_slice_dup (GVariantBuilder, builder);
3594 g_variant_builder_init (builder, type);
3595 GVSB(builder)->parent = parent;
3596
3597 /* push the prev_item_type down into the subcontainer */
3598 if (GVSB(parent)->prev_item_type)
3599 {
3600 if (!GVSB(builder)->uniform_item_types)
3601 /* tuples and dict entries */
3602 GVSB(builder)->prev_item_type =
3603 g_variant_type_first (GVSB(parent)->prev_item_type);
3604
3605 else if (!g_variant_type_is_variant (GVSB(builder)->type))
3606 /* maybes and arrays */
3607 GVSB(builder)->prev_item_type =
3608 g_variant_type_element (GVSB(parent)->prev_item_type);
3609 }
3610 }
3611
3612 /**
3613 * g_variant_builder_close:
3614 * @builder: a #GVariantBuilder
3615 *
3616 * Closes the subcontainer inside the given @builder that was opened by
3617 * the most recent call to g_variant_builder_open().
3618 *
3619 * It is an error to call this function in any way that would create an
3620 * inconsistent value to be constructed (ie: too few values added to the
3621 * subcontainer).
3622 *
3623 * Since: 2.24
3624 **/
3625 void
g_variant_builder_close(GVariantBuilder * builder)3626 g_variant_builder_close (GVariantBuilder *builder)
3627 {
3628 GVariantBuilder *parent;
3629
3630 g_return_if_fail (ensure_valid_builder (builder));
3631 g_return_if_fail (GVSB(builder)->parent != NULL);
3632
3633 parent = GVSB(builder)->parent;
3634 GVSB(builder)->parent = NULL;
3635
3636 g_variant_builder_add_value (parent, g_variant_builder_end (builder));
3637 *builder = *parent;
3638
3639 g_slice_free (GVariantBuilder, parent);
3640 }
3641
3642 /*< private >
3643 * g_variant_make_maybe_type:
3644 * @element: a #GVariant
3645 *
3646 * Return the type of a maybe containing @element.
3647 */
3648 static GVariantType *
g_variant_make_maybe_type(GVariant * element)3649 g_variant_make_maybe_type (GVariant *element)
3650 {
3651 return g_variant_type_new_maybe (g_variant_get_type (element));
3652 }
3653
3654 /*< private >
3655 * g_variant_make_array_type:
3656 * @element: a #GVariant
3657 *
3658 * Return the type of an array containing @element.
3659 */
3660 static GVariantType *
g_variant_make_array_type(GVariant * element)3661 g_variant_make_array_type (GVariant *element)
3662 {
3663 return g_variant_type_new_array (g_variant_get_type (element));
3664 }
3665
3666 /**
3667 * g_variant_builder_end:
3668 * @builder: a #GVariantBuilder
3669 *
3670 * Ends the builder process and returns the constructed value.
3671 *
3672 * It is not permissible to use @builder in any way after this call
3673 * except for reference counting operations (in the case of a
3674 * heap-allocated #GVariantBuilder) or by reinitialising it with
3675 * g_variant_builder_init() (in the case of stack-allocated). This
3676 * means that for the stack-allocated builders there is no need to
3677 * call g_variant_builder_clear() after the call to
3678 * g_variant_builder_end().
3679 *
3680 * It is an error to call this function in any way that would create an
3681 * inconsistent value to be constructed (ie: insufficient number of
3682 * items added to a container with a specific number of children
3683 * required). It is also an error to call this function if the builder
3684 * was created with an indefinite array or maybe type and no children
3685 * have been added; in this case it is impossible to infer the type of
3686 * the empty array.
3687 *
3688 * Returns: (transfer none): a new, floating, #GVariant
3689 *
3690 * Since: 2.24
3691 **/
3692 GVariant *
g_variant_builder_end(GVariantBuilder * builder)3693 g_variant_builder_end (GVariantBuilder *builder)
3694 {
3695 GVariantType *my_type;
3696 GVariant *value;
3697
3698 g_return_val_if_fail (ensure_valid_builder (builder), NULL);
3699 g_return_val_if_fail (GVSB(builder)->offset >= GVSB(builder)->min_items,
3700 NULL);
3701 g_return_val_if_fail (!GVSB(builder)->uniform_item_types ||
3702 GVSB(builder)->prev_item_type != NULL ||
3703 g_variant_type_is_definite (GVSB(builder)->type),
3704 NULL);
3705
3706 if (g_variant_type_is_definite (GVSB(builder)->type))
3707 my_type = g_variant_type_copy (GVSB(builder)->type);
3708
3709 else if (g_variant_type_is_maybe (GVSB(builder)->type))
3710 my_type = g_variant_make_maybe_type (GVSB(builder)->children[0]);
3711
3712 else if (g_variant_type_is_array (GVSB(builder)->type))
3713 my_type = g_variant_make_array_type (GVSB(builder)->children[0]);
3714
3715 else if (g_variant_type_is_tuple (GVSB(builder)->type))
3716 my_type = g_variant_make_tuple_type (GVSB(builder)->children,
3717 GVSB(builder)->offset);
3718
3719 else if (g_variant_type_is_dict_entry (GVSB(builder)->type))
3720 my_type = g_variant_make_dict_entry_type (GVSB(builder)->children[0],
3721 GVSB(builder)->children[1]);
3722 else
3723 g_assert_not_reached ();
3724
3725 value = g_variant_new_from_children (my_type,
3726 g_renew (GVariant *,
3727 GVSB(builder)->children,
3728 GVSB(builder)->offset),
3729 GVSB(builder)->offset,
3730 GVSB(builder)->trusted);
3731 GVSB(builder)->children = NULL;
3732 GVSB(builder)->offset = 0;
3733
3734 g_variant_builder_clear (builder);
3735 g_variant_type_free (my_type);
3736
3737 return value;
3738 }
3739
3740 /* GVariantDict {{{1 */
3741
3742 /**
3743 * GVariantDict:
3744 *
3745 * #GVariantDict is a mutable interface to #GVariant dictionaries.
3746 *
3747 * It can be used for doing a sequence of dictionary lookups in an
3748 * efficient way on an existing #GVariant dictionary or it can be used
3749 * to construct new dictionaries with a hashtable-like interface. It
3750 * can also be used for taking existing dictionaries and modifying them
3751 * in order to create new ones.
3752 *
3753 * #GVariantDict can only be used with %G_VARIANT_TYPE_VARDICT
3754 * dictionaries.
3755 *
3756 * It is possible to use #GVariantDict allocated on the stack or on the
3757 * heap. When using a stack-allocated #GVariantDict, you begin with a
3758 * call to g_variant_dict_init() and free the resources with a call to
3759 * g_variant_dict_clear().
3760 *
3761 * Heap-allocated #GVariantDict follows normal refcounting rules: you
3762 * allocate it with g_variant_dict_new() and use g_variant_dict_ref()
3763 * and g_variant_dict_unref().
3764 *
3765 * g_variant_dict_end() is used to convert the #GVariantDict back into a
3766 * dictionary-type #GVariant. When used with stack-allocated instances,
3767 * this also implicitly frees all associated memory, but for
3768 * heap-allocated instances, you must still call g_variant_dict_unref()
3769 * afterwards.
3770 *
3771 * You will typically want to use a heap-allocated #GVariantDict when
3772 * you expose it as part of an API. For most other uses, the
3773 * stack-allocated form will be more convenient.
3774 *
3775 * Consider the following two examples that do the same thing in each
3776 * style: take an existing dictionary and look up the "count" uint32
3777 * key, adding 1 to it if it is found, or returning an error if the
3778 * key is not found. Each returns the new dictionary as a floating
3779 * #GVariant.
3780 *
3781 * ## Using a stack-allocated GVariantDict
3782 *
3783 * |[<!-- language="C" -->
3784 * GVariant *
3785 * add_to_count (GVariant *orig,
3786 * GError **error)
3787 * {
3788 * GVariantDict dict;
3789 * guint32 count;
3790 *
3791 * g_variant_dict_init (&dict, orig);
3792 * if (!g_variant_dict_lookup (&dict, "count", "u", &count))
3793 * {
3794 * g_set_error (...);
3795 * g_variant_dict_clear (&dict);
3796 * return NULL;
3797 * }
3798 *
3799 * g_variant_dict_insert (&dict, "count", "u", count + 1);
3800 *
3801 * return g_variant_dict_end (&dict);
3802 * }
3803 * ]|
3804 *
3805 * ## Using heap-allocated GVariantDict
3806 *
3807 * |[<!-- language="C" -->
3808 * GVariant *
3809 * add_to_count (GVariant *orig,
3810 * GError **error)
3811 * {
3812 * GVariantDict *dict;
3813 * GVariant *result;
3814 * guint32 count;
3815 *
3816 * dict = g_variant_dict_new (orig);
3817 *
3818 * if (g_variant_dict_lookup (dict, "count", "u", &count))
3819 * {
3820 * g_variant_dict_insert (dict, "count", "u", count + 1);
3821 * result = g_variant_dict_end (dict);
3822 * }
3823 * else
3824 * {
3825 * g_set_error (...);
3826 * result = NULL;
3827 * }
3828 *
3829 * g_variant_dict_unref (dict);
3830 *
3831 * return result;
3832 * }
3833 * ]|
3834 *
3835 * Since: 2.40
3836 **/
3837 struct stack_dict
3838 {
3839 GHashTable *values;
3840 gsize magic;
3841 };
3842
3843 G_STATIC_ASSERT (sizeof (struct stack_dict) <= sizeof (GVariantDict));
3844
3845 struct heap_dict
3846 {
3847 struct stack_dict dict;
3848 gint ref_count;
3849 gsize magic;
3850 };
3851
3852 #define GVSD(d) ((struct stack_dict *) (d))
3853 #define GVHD(d) ((struct heap_dict *) (d))
3854 #define GVSD_MAGIC ((gsize) 2579507750u)
3855 #define GVSD_MAGIC_PARTIAL ((gsize) 3488698669u)
3856 #define GVHD_MAGIC ((gsize) 2450270775u)
3857 #define is_valid_dict(d) (GVSD(d)->magic == GVSD_MAGIC)
3858 #define is_valid_heap_dict(d) (GVHD(d)->magic == GVHD_MAGIC)
3859
3860 /* Just to make sure that by adding a union to GVariantDict, we didn't
3861 * accidentally change ABI. */
3862 G_STATIC_ASSERT (sizeof (GVariantDict) == sizeof (gsize[16]));
3863
3864 static gboolean
ensure_valid_dict(GVariantDict * dict)3865 ensure_valid_dict (GVariantDict *dict)
3866 {
3867 if (dict == NULL)
3868 return FALSE;
3869 else if (is_valid_dict (dict))
3870 return TRUE;
3871 if (dict->u.s.partial_magic == GVSD_MAGIC_PARTIAL)
3872 {
3873 static GVariantDict cleared_dict;
3874
3875 /* Make sure that only first two fields were set and the rest is
3876 * zeroed to avoid messing up the builder that had parent
3877 * address equal to GVSB_MAGIC_PARTIAL. */
3878 if (memcmp (cleared_dict.u.s.y, dict->u.s.y, sizeof cleared_dict.u.s.y))
3879 return FALSE;
3880
3881 g_variant_dict_init (dict, dict->u.s.asv);
3882 }
3883 return is_valid_dict (dict);
3884 }
3885
3886 /**
3887 * g_variant_dict_new:
3888 * @from_asv: (nullable): the #GVariant with which to initialise the
3889 * dictionary
3890 *
3891 * Allocates and initialises a new #GVariantDict.
3892 *
3893 * You should call g_variant_dict_unref() on the return value when it
3894 * is no longer needed. The memory will not be automatically freed by
3895 * any other call.
3896 *
3897 * In some cases it may be easier to place a #GVariantDict directly on
3898 * the stack of the calling function and initialise it with
3899 * g_variant_dict_init(). This is particularly useful when you are
3900 * using #GVariantDict to construct a #GVariant.
3901 *
3902 * Returns: (transfer full): a #GVariantDict
3903 *
3904 * Since: 2.40
3905 **/
3906 GVariantDict *
g_variant_dict_new(GVariant * from_asv)3907 g_variant_dict_new (GVariant *from_asv)
3908 {
3909 GVariantDict *dict;
3910
3911 dict = g_slice_alloc (sizeof (struct heap_dict));
3912 g_variant_dict_init (dict, from_asv);
3913 GVHD(dict)->magic = GVHD_MAGIC;
3914 GVHD(dict)->ref_count = 1;
3915
3916 return dict;
3917 }
3918
3919 /**
3920 * g_variant_dict_init: (skip)
3921 * @dict: a #GVariantDict
3922 * @from_asv: (nullable): the initial value for @dict
3923 *
3924 * Initialises a #GVariantDict structure.
3925 *
3926 * If @from_asv is given, it is used to initialise the dictionary.
3927 *
3928 * This function completely ignores the previous contents of @dict. On
3929 * one hand this means that it is valid to pass in completely
3930 * uninitialised memory. On the other hand, this means that if you are
3931 * initialising over top of an existing #GVariantDict you need to first
3932 * call g_variant_dict_clear() in order to avoid leaking memory.
3933 *
3934 * You must not call g_variant_dict_ref() or g_variant_dict_unref() on a
3935 * #GVariantDict that was initialised with this function. If you ever
3936 * pass a reference to a #GVariantDict outside of the control of your
3937 * own code then you should assume that the person receiving that
3938 * reference may try to use reference counting; you should use
3939 * g_variant_dict_new() instead of this function.
3940 *
3941 * Since: 2.40
3942 **/
3943 void
g_variant_dict_init(GVariantDict * dict,GVariant * from_asv)3944 g_variant_dict_init (GVariantDict *dict,
3945 GVariant *from_asv)
3946 {
3947 GVariantIter iter;
3948 gchar *key;
3949 GVariant *value;
3950
3951 GVSD(dict)->values = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, (GDestroyNotify) g_variant_unref);
3952 GVSD(dict)->magic = GVSD_MAGIC;
3953
3954 if (from_asv)
3955 {
3956 g_variant_iter_init (&iter, from_asv);
3957 while (g_variant_iter_next (&iter, "{sv}", &key, &value))
3958 g_hash_table_insert (GVSD(dict)->values, key, value);
3959 }
3960 }
3961
3962 /**
3963 * g_variant_dict_lookup:
3964 * @dict: a #GVariantDict
3965 * @key: the key to look up in the dictionary
3966 * @format_string: a GVariant format string
3967 * @...: the arguments to unpack the value into
3968 *
3969 * Looks up a value in a #GVariantDict.
3970 *
3971 * This function is a wrapper around g_variant_dict_lookup_value() and
3972 * g_variant_get(). In the case that %NULL would have been returned,
3973 * this function returns %FALSE. Otherwise, it unpacks the returned
3974 * value and returns %TRUE.
3975 *
3976 * @format_string determines the C types that are used for unpacking the
3977 * values and also determines if the values are copied or borrowed, see the
3978 * section on [GVariant format strings][gvariant-format-strings-pointers].
3979 *
3980 * Returns: %TRUE if a value was unpacked
3981 *
3982 * Since: 2.40
3983 **/
3984 gboolean
g_variant_dict_lookup(GVariantDict * dict,const gchar * key,const gchar * format_string,...)3985 g_variant_dict_lookup (GVariantDict *dict,
3986 const gchar *key,
3987 const gchar *format_string,
3988 ...)
3989 {
3990 GVariant *value;
3991 va_list ap;
3992
3993 g_return_val_if_fail (ensure_valid_dict (dict), FALSE);
3994 g_return_val_if_fail (key != NULL, FALSE);
3995 g_return_val_if_fail (format_string != NULL, FALSE);
3996
3997 value = g_hash_table_lookup (GVSD(dict)->values, key);
3998
3999 if (value == NULL || !g_variant_check_format_string (value, format_string, FALSE))
4000 return FALSE;
4001
4002 va_start (ap, format_string);
4003 g_variant_get_va (value, format_string, NULL, &ap);
4004 va_end (ap);
4005
4006 return TRUE;
4007 }
4008
4009 /**
4010 * g_variant_dict_lookup_value:
4011 * @dict: a #GVariantDict
4012 * @key: the key to look up in the dictionary
4013 * @expected_type: (nullable): a #GVariantType, or %NULL
4014 *
4015 * Looks up a value in a #GVariantDict.
4016 *
4017 * If @key is not found in @dictionary, %NULL is returned.
4018 *
4019 * The @expected_type string specifies what type of value is expected.
4020 * If the value associated with @key has a different type then %NULL is
4021 * returned.
4022 *
4023 * If the key is found and the value has the correct type, it is
4024 * returned. If @expected_type was specified then any non-%NULL return
4025 * value will have this type.
4026 *
4027 * Returns: (transfer full): the value of the dictionary key, or %NULL
4028 *
4029 * Since: 2.40
4030 **/
4031 GVariant *
g_variant_dict_lookup_value(GVariantDict * dict,const gchar * key,const GVariantType * expected_type)4032 g_variant_dict_lookup_value (GVariantDict *dict,
4033 const gchar *key,
4034 const GVariantType *expected_type)
4035 {
4036 GVariant *result;
4037
4038 g_return_val_if_fail (ensure_valid_dict (dict), NULL);
4039 g_return_val_if_fail (key != NULL, NULL);
4040
4041 result = g_hash_table_lookup (GVSD(dict)->values, key);
4042
4043 if (result && (!expected_type || g_variant_is_of_type (result, expected_type)))
4044 return g_variant_ref (result);
4045
4046 return NULL;
4047 }
4048
4049 /**
4050 * g_variant_dict_contains:
4051 * @dict: a #GVariantDict
4052 * @key: the key to look up in the dictionary
4053 *
4054 * Checks if @key exists in @dict.
4055 *
4056 * Returns: %TRUE if @key is in @dict
4057 *
4058 * Since: 2.40
4059 **/
4060 gboolean
g_variant_dict_contains(GVariantDict * dict,const gchar * key)4061 g_variant_dict_contains (GVariantDict *dict,
4062 const gchar *key)
4063 {
4064 g_return_val_if_fail (ensure_valid_dict (dict), FALSE);
4065 g_return_val_if_fail (key != NULL, FALSE);
4066
4067 return g_hash_table_contains (GVSD(dict)->values, key);
4068 }
4069
4070 /**
4071 * g_variant_dict_insert:
4072 * @dict: a #GVariantDict
4073 * @key: the key to insert a value for
4074 * @format_string: a #GVariant varargs format string
4075 * @...: arguments, as per @format_string
4076 *
4077 * Inserts a value into a #GVariantDict.
4078 *
4079 * This call is a convenience wrapper that is exactly equivalent to
4080 * calling g_variant_new() followed by g_variant_dict_insert_value().
4081 *
4082 * Since: 2.40
4083 **/
4084 void
g_variant_dict_insert(GVariantDict * dict,const gchar * key,const gchar * format_string,...)4085 g_variant_dict_insert (GVariantDict *dict,
4086 const gchar *key,
4087 const gchar *format_string,
4088 ...)
4089 {
4090 va_list ap;
4091
4092 g_return_if_fail (ensure_valid_dict (dict));
4093 g_return_if_fail (key != NULL);
4094 g_return_if_fail (format_string != NULL);
4095
4096 va_start (ap, format_string);
4097 g_variant_dict_insert_value (dict, key, g_variant_new_va (format_string, NULL, &ap));
4098 va_end (ap);
4099 }
4100
4101 /**
4102 * g_variant_dict_insert_value:
4103 * @dict: a #GVariantDict
4104 * @key: the key to insert a value for
4105 * @value: the value to insert
4106 *
4107 * Inserts (or replaces) a key in a #GVariantDict.
4108 *
4109 * @value is consumed if it is floating.
4110 *
4111 * Since: 2.40
4112 **/
4113 void
g_variant_dict_insert_value(GVariantDict * dict,const gchar * key,GVariant * value)4114 g_variant_dict_insert_value (GVariantDict *dict,
4115 const gchar *key,
4116 GVariant *value)
4117 {
4118 g_return_if_fail (ensure_valid_dict (dict));
4119 g_return_if_fail (key != NULL);
4120 g_return_if_fail (value != NULL);
4121
4122 g_hash_table_insert (GVSD(dict)->values, g_strdup (key), g_variant_ref_sink (value));
4123 }
4124
4125 /**
4126 * g_variant_dict_remove:
4127 * @dict: a #GVariantDict
4128 * @key: the key to remove
4129 *
4130 * Removes a key and its associated value from a #GVariantDict.
4131 *
4132 * Returns: %TRUE if the key was found and removed
4133 *
4134 * Since: 2.40
4135 **/
4136 gboolean
g_variant_dict_remove(GVariantDict * dict,const gchar * key)4137 g_variant_dict_remove (GVariantDict *dict,
4138 const gchar *key)
4139 {
4140 g_return_val_if_fail (ensure_valid_dict (dict), FALSE);
4141 g_return_val_if_fail (key != NULL, FALSE);
4142
4143 return g_hash_table_remove (GVSD(dict)->values, key);
4144 }
4145
4146 /**
4147 * g_variant_dict_clear:
4148 * @dict: a #GVariantDict
4149 *
4150 * Releases all memory associated with a #GVariantDict without freeing
4151 * the #GVariantDict structure itself.
4152 *
4153 * It typically only makes sense to do this on a stack-allocated
4154 * #GVariantDict if you want to abort building the value part-way
4155 * through. This function need not be called if you call
4156 * g_variant_dict_end() and it also doesn't need to be called on dicts
4157 * allocated with g_variant_dict_new (see g_variant_dict_unref() for
4158 * that).
4159 *
4160 * It is valid to call this function on either an initialised
4161 * #GVariantDict or one that was previously cleared by an earlier call
4162 * to g_variant_dict_clear() but it is not valid to call this function
4163 * on uninitialised memory.
4164 *
4165 * Since: 2.40
4166 **/
4167 void
g_variant_dict_clear(GVariantDict * dict)4168 g_variant_dict_clear (GVariantDict *dict)
4169 {
4170 if (GVSD(dict)->magic == 0)
4171 /* all-zeros case */
4172 return;
4173
4174 g_return_if_fail (ensure_valid_dict (dict));
4175
4176 g_hash_table_unref (GVSD(dict)->values);
4177 GVSD(dict)->values = NULL;
4178
4179 GVSD(dict)->magic = 0;
4180 }
4181
4182 /**
4183 * g_variant_dict_end:
4184 * @dict: a #GVariantDict
4185 *
4186 * Returns the current value of @dict as a #GVariant of type
4187 * %G_VARIANT_TYPE_VARDICT, clearing it in the process.
4188 *
4189 * It is not permissible to use @dict in any way after this call except
4190 * for reference counting operations (in the case of a heap-allocated
4191 * #GVariantDict) or by reinitialising it with g_variant_dict_init() (in
4192 * the case of stack-allocated).
4193 *
4194 * Returns: (transfer none): a new, floating, #GVariant
4195 *
4196 * Since: 2.40
4197 **/
4198 GVariant *
g_variant_dict_end(GVariantDict * dict)4199 g_variant_dict_end (GVariantDict *dict)
4200 {
4201 GVariantBuilder builder;
4202 GHashTableIter iter;
4203 gpointer key, value;
4204
4205 g_return_val_if_fail (ensure_valid_dict (dict), NULL);
4206
4207 g_variant_builder_init (&builder, G_VARIANT_TYPE_VARDICT);
4208
4209 g_hash_table_iter_init (&iter, GVSD(dict)->values);
4210 while (g_hash_table_iter_next (&iter, &key, &value))
4211 g_variant_builder_add (&builder, "{sv}", (const gchar *) key, (GVariant *) value);
4212
4213 g_variant_dict_clear (dict);
4214
4215 return g_variant_builder_end (&builder);
4216 }
4217
4218 /**
4219 * g_variant_dict_ref:
4220 * @dict: a heap-allocated #GVariantDict
4221 *
4222 * Increases the reference count on @dict.
4223 *
4224 * Don't call this on stack-allocated #GVariantDict instances or bad
4225 * things will happen.
4226 *
4227 * Returns: (transfer full): a new reference to @dict
4228 *
4229 * Since: 2.40
4230 **/
4231 GVariantDict *
g_variant_dict_ref(GVariantDict * dict)4232 g_variant_dict_ref (GVariantDict *dict)
4233 {
4234 g_return_val_if_fail (is_valid_heap_dict (dict), NULL);
4235
4236 GVHD(dict)->ref_count++;
4237
4238 return dict;
4239 }
4240
4241 /**
4242 * g_variant_dict_unref:
4243 * @dict: (transfer full): a heap-allocated #GVariantDict
4244 *
4245 * Decreases the reference count on @dict.
4246 *
4247 * In the event that there are no more references, releases all memory
4248 * associated with the #GVariantDict.
4249 *
4250 * Don't call this on stack-allocated #GVariantDict instances or bad
4251 * things will happen.
4252 *
4253 * Since: 2.40
4254 **/
4255 void
g_variant_dict_unref(GVariantDict * dict)4256 g_variant_dict_unref (GVariantDict *dict)
4257 {
4258 g_return_if_fail (is_valid_heap_dict (dict));
4259
4260 if (--GVHD(dict)->ref_count == 0)
4261 {
4262 g_variant_dict_clear (dict);
4263 g_slice_free (struct heap_dict, (struct heap_dict *) dict);
4264 }
4265 }
4266
4267
4268 /* Format strings {{{1 */
4269 /*< private >
4270 * g_variant_format_string_scan:
4271 * @string: a string that may be prefixed with a format string
4272 * @limit: (nullable) (default NULL): a pointer to the end of @string,
4273 * or %NULL
4274 * @endptr: (nullable) (default NULL): location to store the end pointer,
4275 * or %NULL
4276 *
4277 * Checks the string pointed to by @string for starting with a properly
4278 * formed #GVariant varargs format string. If no valid format string is
4279 * found then %FALSE is returned.
4280 *
4281 * If @string does start with a valid format string then %TRUE is
4282 * returned. If @endptr is non-%NULL then it is updated to point to the
4283 * first character after the format string.
4284 *
4285 * If @limit is non-%NULL then @limit (and any character after it) will
4286 * not be accessed and the effect is otherwise equivalent to if the
4287 * character at @limit were nul.
4288 *
4289 * See the section on [GVariant format strings][gvariant-format-strings].
4290 *
4291 * Returns: %TRUE if there was a valid format string
4292 *
4293 * Since: 2.24
4294 */
4295 gboolean
g_variant_format_string_scan(const gchar * string,const gchar * limit,const gchar ** endptr)4296 g_variant_format_string_scan (const gchar *string,
4297 const gchar *limit,
4298 const gchar **endptr)
4299 {
4300 #define next_char() (string == limit ? '\0' : *(string++))
4301 #define peek_char() (string == limit ? '\0' : *string)
4302 char c;
4303
4304 switch (next_char())
4305 {
4306 case 'b': case 'y': case 'n': case 'q': case 'i': case 'u':
4307 case 'x': case 't': case 'h': case 'd': case 's': case 'o':
4308 case 'g': case 'v': case '*': case '?': case 'r':
4309 break;
4310
4311 case 'm':
4312 return g_variant_format_string_scan (string, limit, endptr);
4313
4314 case 'a':
4315 case '@':
4316 return g_variant_type_string_scan (string, limit, endptr);
4317
4318 case '(':
4319 while (peek_char() != ')')
4320 if (!g_variant_format_string_scan (string, limit, &string))
4321 return FALSE;
4322
4323 next_char(); /* consume ')' */
4324 break;
4325
4326 case '{':
4327 c = next_char();
4328
4329 if (c == '&')
4330 {
4331 c = next_char ();
4332
4333 if (c != 's' && c != 'o' && c != 'g')
4334 return FALSE;
4335 }
4336 else
4337 {
4338 if (c == '@')
4339 c = next_char ();
4340
4341 /* ISO/IEC 9899:1999 (C99) §7.21.5.2:
4342 * The terminating null character is considered to be
4343 * part of the string.
4344 */
4345 if (c != '\0' && strchr ("bynqiuxthdsog?", c) == NULL)
4346 return FALSE;
4347 }
4348
4349 if (!g_variant_format_string_scan (string, limit, &string))
4350 return FALSE;
4351
4352 if (next_char() != '}')
4353 return FALSE;
4354
4355 break;
4356
4357 case '^':
4358 if ((c = next_char()) == 'a')
4359 {
4360 if ((c = next_char()) == '&')
4361 {
4362 if ((c = next_char()) == 'a')
4363 {
4364 if ((c = next_char()) == 'y')
4365 break; /* '^a&ay' */
4366 }
4367
4368 else if (c == 's' || c == 'o')
4369 break; /* '^a&s', '^a&o' */
4370 }
4371
4372 else if (c == 'a')
4373 {
4374 if ((c = next_char()) == 'y')
4375 break; /* '^aay' */
4376 }
4377
4378 else if (c == 's' || c == 'o')
4379 break; /* '^as', '^ao' */
4380
4381 else if (c == 'y')
4382 break; /* '^ay' */
4383 }
4384 else if (c == '&')
4385 {
4386 if ((c = next_char()) == 'a')
4387 {
4388 if ((c = next_char()) == 'y')
4389 break; /* '^&ay' */
4390 }
4391 }
4392
4393 return FALSE;
4394
4395 case '&':
4396 c = next_char();
4397
4398 if (c != 's' && c != 'o' && c != 'g')
4399 return FALSE;
4400
4401 break;
4402
4403 default:
4404 return FALSE;
4405 }
4406
4407 if (endptr != NULL)
4408 *endptr = string;
4409
4410 #undef next_char
4411 #undef peek_char
4412
4413 return TRUE;
4414 }
4415
4416 /**
4417 * g_variant_check_format_string:
4418 * @value: a #GVariant
4419 * @format_string: a valid #GVariant format string
4420 * @copy_only: %TRUE to ensure the format string makes deep copies
4421 *
4422 * Checks if calling g_variant_get() with @format_string on @value would
4423 * be valid from a type-compatibility standpoint. @format_string is
4424 * assumed to be a valid format string (from a syntactic standpoint).
4425 *
4426 * If @copy_only is %TRUE then this function additionally checks that it
4427 * would be safe to call g_variant_unref() on @value immediately after
4428 * the call to g_variant_get() without invalidating the result. This is
4429 * only possible if deep copies are made (ie: there are no pointers to
4430 * the data inside of the soon-to-be-freed #GVariant instance). If this
4431 * check fails then a g_critical() is printed and %FALSE is returned.
4432 *
4433 * This function is meant to be used by functions that wish to provide
4434 * varargs accessors to #GVariant values of uncertain values (eg:
4435 * g_variant_lookup() or g_menu_model_get_item_attribute()).
4436 *
4437 * Returns: %TRUE if @format_string is safe to use
4438 *
4439 * Since: 2.34
4440 */
4441 gboolean
g_variant_check_format_string(GVariant * value,const gchar * format_string,gboolean copy_only)4442 g_variant_check_format_string (GVariant *value,
4443 const gchar *format_string,
4444 gboolean copy_only)
4445 {
4446 const gchar *original_format = format_string;
4447 const gchar *type_string;
4448
4449 /* Interesting factoid: assuming a format string is valid, it can be
4450 * converted to a type string by removing all '@' '&' and '^'
4451 * characters.
4452 *
4453 * Instead of doing that, we can just skip those characters when
4454 * comparing it to the type string of @value.
4455 *
4456 * For the copy-only case we can just drop the '&' from the list of
4457 * characters to skip over. A '&' will never appear in a type string
4458 * so we know that it won't be possible to return %TRUE if it is in a
4459 * format string.
4460 */
4461 type_string = g_variant_get_type_string (value);
4462
4463 while (*type_string || *format_string)
4464 {
4465 gchar format = *format_string++;
4466
4467 switch (format)
4468 {
4469 case '&':
4470 if G_UNLIKELY (copy_only)
4471 {
4472 /* for the love of all that is good, please don't mark this string for translation... */
4473 g_critical ("g_variant_check_format_string() is being called by a function with a GVariant varargs "
4474 "interface to validate the passed format string for type safety. The passed format "
4475 "(%s) contains a '&' character which would result in a pointer being returned to the "
4476 "data inside of a GVariant instance that may no longer exist by the time the function "
4477 "returns. Modify your code to use a format string without '&'.", original_format);
4478 return FALSE;
4479 }
4480
4481 G_GNUC_FALLTHROUGH;
4482 case '^':
4483 case '@':
4484 /* ignore these 2 (or 3) */
4485 continue;
4486
4487 case '?':
4488 /* attempt to consume one of 'bynqiuxthdsog' */
4489 {
4490 char s = *type_string++;
4491
4492 if (s == '\0' || strchr ("bynqiuxthdsog", s) == NULL)
4493 return FALSE;
4494 }
4495 continue;
4496
4497 case 'r':
4498 /* ensure it's a tuple */
4499 if (*type_string != '(')
4500 return FALSE;
4501
4502 G_GNUC_FALLTHROUGH;
4503 case '*':
4504 /* consume a full type string for the '*' or 'r' */
4505 if (!g_variant_type_string_scan (type_string, NULL, &type_string))
4506 return FALSE;
4507
4508 continue;
4509
4510 default:
4511 /* attempt to consume exactly one character equal to the format */
4512 if (format != *type_string++)
4513 return FALSE;
4514 }
4515 }
4516
4517 return TRUE;
4518 }
4519
4520 /*< private >
4521 * g_variant_format_string_scan_type:
4522 * @string: a string that may be prefixed with a format string
4523 * @limit: (nullable) (default NULL): a pointer to the end of @string,
4524 * or %NULL
4525 * @endptr: (nullable) (default NULL): location to store the end pointer,
4526 * or %NULL
4527 *
4528 * If @string starts with a valid format string then this function will
4529 * return the type that the format string corresponds to. Otherwise
4530 * this function returns %NULL.
4531 *
4532 * Use g_variant_type_free() to free the return value when you no longer
4533 * need it.
4534 *
4535 * This function is otherwise exactly like
4536 * g_variant_format_string_scan().
4537 *
4538 * Returns: (nullable): a #GVariantType if there was a valid format string
4539 *
4540 * Since: 2.24
4541 */
4542 GVariantType *
g_variant_format_string_scan_type(const gchar * string,const gchar * limit,const gchar ** endptr)4543 g_variant_format_string_scan_type (const gchar *string,
4544 const gchar *limit,
4545 const gchar **endptr)
4546 {
4547 const gchar *my_end;
4548 gchar *dest;
4549 gchar *new;
4550
4551 if (endptr == NULL)
4552 endptr = &my_end;
4553
4554 if (!g_variant_format_string_scan (string, limit, endptr))
4555 return NULL;
4556
4557 dest = new = g_malloc (*endptr - string + 1);
4558 while (string != *endptr)
4559 {
4560 if (*string != '@' && *string != '&' && *string != '^')
4561 *dest++ = *string;
4562 string++;
4563 }
4564 *dest = '\0';
4565
4566 return (GVariantType *) G_VARIANT_TYPE (new);
4567 }
4568
4569 static gboolean
valid_format_string(const gchar * format_string,gboolean single,GVariant * value)4570 valid_format_string (const gchar *format_string,
4571 gboolean single,
4572 GVariant *value)
4573 {
4574 const gchar *endptr;
4575 GVariantType *type;
4576
4577 type = g_variant_format_string_scan_type (format_string, NULL, &endptr);
4578
4579 if G_UNLIKELY (type == NULL || (single && *endptr != '\0'))
4580 {
4581 if (single)
4582 g_critical ("'%s' is not a valid GVariant format string",
4583 format_string);
4584 else
4585 g_critical ("'%s' does not have a valid GVariant format "
4586 "string as a prefix", format_string);
4587
4588 if (type != NULL)
4589 g_variant_type_free (type);
4590
4591 return FALSE;
4592 }
4593
4594 if G_UNLIKELY (value && !g_variant_is_of_type (value, type))
4595 {
4596 gchar *fragment;
4597 gchar *typestr;
4598
4599 fragment = g_strndup (format_string, endptr - format_string);
4600 typestr = g_variant_type_dup_string (type);
4601
4602 g_critical ("the GVariant format string '%s' has a type of "
4603 "'%s' but the given value has a type of '%s'",
4604 fragment, typestr, g_variant_get_type_string (value));
4605
4606 g_variant_type_free (type);
4607 g_free (fragment);
4608 g_free (typestr);
4609
4610 return FALSE;
4611 }
4612
4613 g_variant_type_free (type);
4614
4615 return TRUE;
4616 }
4617
4618 /* Variable Arguments {{{1 */
4619 /* We consider 2 main classes of format strings:
4620 *
4621 * - recursive format strings
4622 * these are ones that result in recursion and the collection of
4623 * possibly more than one argument. Maybe types, tuples,
4624 * dictionary entries.
4625 *
4626 * - leaf format string
4627 * these result in the collection of a single argument.
4628 *
4629 * Leaf format strings are further subdivided into two categories:
4630 *
4631 * - single non-null pointer ("nnp")
4632 * these either collect or return a single non-null pointer.
4633 *
4634 * - other
4635 * these collect or return something else (bool, number, etc).
4636 *
4637 * Based on the above, the varargs handling code is split into 4 main parts:
4638 *
4639 * - nnp handling code
4640 * - leaf handling code (which may invoke nnp code)
4641 * - generic handling code (may be recursive, may invoke leaf code)
4642 * - user-facing API (which invokes the generic code)
4643 *
4644 * Each section implements some of the following functions:
4645 *
4646 * - skip:
4647 * collect the arguments for the format string as if
4648 * g_variant_new() had been called, but do nothing with them. used
4649 * for skipping over arguments when constructing a Nothing maybe
4650 * type.
4651 *
4652 * - new:
4653 * create a GVariant *
4654 *
4655 * - get:
4656 * unpack a GVariant *
4657 *
4658 * - free (nnp only):
4659 * free a previously allocated item
4660 */
4661
4662 static gboolean
g_variant_format_string_is_leaf(const gchar * str)4663 g_variant_format_string_is_leaf (const gchar *str)
4664 {
4665 return str[0] != 'm' && str[0] != '(' && str[0] != '{';
4666 }
4667
4668 static gboolean
g_variant_format_string_is_nnp(const gchar * str)4669 g_variant_format_string_is_nnp (const gchar *str)
4670 {
4671 return str[0] == 'a' || str[0] == 's' || str[0] == 'o' || str[0] == 'g' ||
4672 str[0] == '^' || str[0] == '@' || str[0] == '*' || str[0] == '?' ||
4673 str[0] == 'r' || str[0] == 'v' || str[0] == '&';
4674 }
4675
4676 /* Single non-null pointer ("nnp") {{{2 */
4677 static void
g_variant_valist_free_nnp(const gchar * str,gpointer ptr)4678 g_variant_valist_free_nnp (const gchar *str,
4679 gpointer ptr)
4680 {
4681 switch (*str)
4682 {
4683 case 'a':
4684 g_variant_iter_free (ptr);
4685 break;
4686
4687 case '^':
4688 if (g_str_has_suffix (str, "y"))
4689 {
4690 if (str[2] != 'a') /* '^a&ay', '^ay' */
4691 g_free (ptr);
4692 else if (str[1] == 'a') /* '^aay' */
4693 g_strfreev (ptr);
4694 break; /* '^&ay' */
4695 }
4696 else if (str[2] != '&') /* '^as', '^ao' */
4697 g_strfreev (ptr);
4698 else /* '^a&s', '^a&o' */
4699 g_free (ptr);
4700 break;
4701
4702 case 's':
4703 case 'o':
4704 case 'g':
4705 g_free (ptr);
4706 break;
4707
4708 case '@':
4709 case '*':
4710 case '?':
4711 case 'v':
4712 g_variant_unref (ptr);
4713 break;
4714
4715 case '&':
4716 break;
4717
4718 default:
4719 g_assert_not_reached ();
4720 }
4721 }
4722
4723 static gchar
g_variant_scan_convenience(const gchar ** str,gboolean * constant,guint * arrays)4724 g_variant_scan_convenience (const gchar **str,
4725 gboolean *constant,
4726 guint *arrays)
4727 {
4728 *constant = FALSE;
4729 *arrays = 0;
4730
4731 for (;;)
4732 {
4733 char c = *(*str)++;
4734
4735 if (c == '&')
4736 *constant = TRUE;
4737
4738 else if (c == 'a')
4739 (*arrays)++;
4740
4741 else
4742 return c;
4743 }
4744 }
4745
4746 static GVariant *
g_variant_valist_new_nnp(const gchar ** str,gpointer ptr)4747 g_variant_valist_new_nnp (const gchar **str,
4748 gpointer ptr)
4749 {
4750 if (**str == '&')
4751 (*str)++;
4752
4753 switch (*(*str)++)
4754 {
4755 case 'a':
4756 if (ptr != NULL)
4757 {
4758 const GVariantType *type;
4759 GVariant *value;
4760
4761 value = g_variant_builder_end (ptr);
4762 type = g_variant_get_type (value);
4763
4764 if G_UNLIKELY (!g_variant_type_is_array (type))
4765 g_error ("g_variant_new: expected array GVariantBuilder but "
4766 "the built value has type '%s'",
4767 g_variant_get_type_string (value));
4768
4769 type = g_variant_type_element (type);
4770
4771 if G_UNLIKELY (!g_variant_type_is_subtype_of (type, (GVariantType *) *str))
4772 {
4773 gchar *type_string = g_variant_type_dup_string ((GVariantType *) *str);
4774 g_error ("g_variant_new: expected GVariantBuilder array element "
4775 "type '%s' but the built value has element type '%s'",
4776 type_string, g_variant_get_type_string (value) + 1);
4777 g_free (type_string);
4778 }
4779
4780 g_variant_type_string_scan (*str, NULL, str);
4781
4782 return value;
4783 }
4784 else
4785
4786 /* special case: NULL pointer for empty array */
4787 {
4788 const GVariantType *type = (GVariantType *) *str;
4789
4790 g_variant_type_string_scan (*str, NULL, str);
4791
4792 if G_UNLIKELY (!g_variant_type_is_definite (type))
4793 g_error ("g_variant_new: NULL pointer given with indefinite "
4794 "array type; unable to determine which type of empty "
4795 "array to construct.");
4796
4797 return g_variant_new_array (type, NULL, 0);
4798 }
4799
4800 case 's':
4801 {
4802 GVariant *value;
4803
4804 value = g_variant_new_string (ptr);
4805
4806 if (value == NULL)
4807 value = g_variant_new_string ("[Invalid UTF-8]");
4808
4809 return value;
4810 }
4811
4812 case 'o':
4813 return g_variant_new_object_path (ptr);
4814
4815 case 'g':
4816 return g_variant_new_signature (ptr);
4817
4818 case '^':
4819 {
4820 gboolean constant;
4821 guint arrays;
4822 gchar type;
4823
4824 type = g_variant_scan_convenience (str, &constant, &arrays);
4825
4826 if (type == 's')
4827 return g_variant_new_strv (ptr, -1);
4828
4829 if (type == 'o')
4830 return g_variant_new_objv (ptr, -1);
4831
4832 if (arrays > 1)
4833 return g_variant_new_bytestring_array (ptr, -1);
4834
4835 return g_variant_new_bytestring (ptr);
4836 }
4837
4838 case '@':
4839 if G_UNLIKELY (!g_variant_is_of_type (ptr, (GVariantType *) *str))
4840 {
4841 gchar *type_string = g_variant_type_dup_string ((GVariantType *) *str);
4842 g_error ("g_variant_new: expected GVariant of type '%s' but "
4843 "received value has type '%s'",
4844 type_string, g_variant_get_type_string (ptr));
4845 g_free (type_string);
4846 }
4847
4848 g_variant_type_string_scan (*str, NULL, str);
4849
4850 return ptr;
4851
4852 case '*':
4853 return ptr;
4854
4855 case '?':
4856 if G_UNLIKELY (!g_variant_type_is_basic (g_variant_get_type (ptr)))
4857 g_error ("g_variant_new: format string '?' expects basic-typed "
4858 "GVariant, but received value has type '%s'",
4859 g_variant_get_type_string (ptr));
4860
4861 return ptr;
4862
4863 case 'r':
4864 if G_UNLIKELY (!g_variant_type_is_tuple (g_variant_get_type (ptr)))
4865 g_error ("g_variant_new: format string 'r' expects tuple-typed "
4866 "GVariant, but received value has type '%s'",
4867 g_variant_get_type_string (ptr));
4868
4869 return ptr;
4870
4871 case 'v':
4872 return g_variant_new_variant (ptr);
4873
4874 default:
4875 g_assert_not_reached ();
4876 }
4877 }
4878
4879 static gpointer
g_variant_valist_get_nnp(const gchar ** str,GVariant * value)4880 g_variant_valist_get_nnp (const gchar **str,
4881 GVariant *value)
4882 {
4883 switch (*(*str)++)
4884 {
4885 case 'a':
4886 g_variant_type_string_scan (*str, NULL, str);
4887 return g_variant_iter_new (value);
4888
4889 case '&':
4890 (*str)++;
4891 return (gchar *) g_variant_get_string (value, NULL);
4892
4893 case 's':
4894 case 'o':
4895 case 'g':
4896 return g_variant_dup_string (value, NULL);
4897
4898 case '^':
4899 {
4900 gboolean constant;
4901 guint arrays;
4902 gchar type;
4903
4904 type = g_variant_scan_convenience (str, &constant, &arrays);
4905
4906 if (type == 's')
4907 {
4908 if (constant)
4909 return g_variant_get_strv (value, NULL);
4910 else
4911 return g_variant_dup_strv (value, NULL);
4912 }
4913
4914 else if (type == 'o')
4915 {
4916 if (constant)
4917 return g_variant_get_objv (value, NULL);
4918 else
4919 return g_variant_dup_objv (value, NULL);
4920 }
4921
4922 else if (arrays > 1)
4923 {
4924 if (constant)
4925 return g_variant_get_bytestring_array (value, NULL);
4926 else
4927 return g_variant_dup_bytestring_array (value, NULL);
4928 }
4929
4930 else
4931 {
4932 if (constant)
4933 return (gchar *) g_variant_get_bytestring (value);
4934 else
4935 return g_variant_dup_bytestring (value, NULL);
4936 }
4937 }
4938
4939 case '@':
4940 g_variant_type_string_scan (*str, NULL, str);
4941 G_GNUC_FALLTHROUGH;
4942
4943 case '*':
4944 case '?':
4945 case 'r':
4946 return g_variant_ref (value);
4947
4948 case 'v':
4949 return g_variant_get_variant (value);
4950
4951 default:
4952 g_assert_not_reached ();
4953 }
4954 }
4955
4956 /* Leaves {{{2 */
4957 static void
g_variant_valist_skip_leaf(const gchar ** str,va_list * app)4958 g_variant_valist_skip_leaf (const gchar **str,
4959 va_list *app)
4960 {
4961 if (g_variant_format_string_is_nnp (*str))
4962 {
4963 g_variant_format_string_scan (*str, NULL, str);
4964 va_arg (*app, gpointer);
4965 return;
4966 }
4967
4968 switch (*(*str)++)
4969 {
4970 case 'b':
4971 case 'y':
4972 case 'n':
4973 case 'q':
4974 case 'i':
4975 case 'u':
4976 case 'h':
4977 va_arg (*app, int);
4978 return;
4979
4980 case 'x':
4981 case 't':
4982 va_arg (*app, guint64);
4983 return;
4984
4985 case 'd':
4986 va_arg (*app, gdouble);
4987 return;
4988
4989 default:
4990 g_assert_not_reached ();
4991 }
4992 }
4993
4994 static GVariant *
g_variant_valist_new_leaf(const gchar ** str,va_list * app)4995 g_variant_valist_new_leaf (const gchar **str,
4996 va_list *app)
4997 {
4998 if (g_variant_format_string_is_nnp (*str))
4999 return g_variant_valist_new_nnp (str, va_arg (*app, gpointer));
5000
5001 switch (*(*str)++)
5002 {
5003 case 'b':
5004 return g_variant_new_boolean (va_arg (*app, gboolean));
5005
5006 case 'y':
5007 return g_variant_new_byte (va_arg (*app, guint));
5008
5009 case 'n':
5010 return g_variant_new_int16 (va_arg (*app, gint));
5011
5012 case 'q':
5013 return g_variant_new_uint16 (va_arg (*app, guint));
5014
5015 case 'i':
5016 return g_variant_new_int32 (va_arg (*app, gint));
5017
5018 case 'u':
5019 return g_variant_new_uint32 (va_arg (*app, guint));
5020
5021 case 'x':
5022 return g_variant_new_int64 (va_arg (*app, gint64));
5023
5024 case 't':
5025 return g_variant_new_uint64 (va_arg (*app, guint64));
5026
5027 case 'h':
5028 return g_variant_new_handle (va_arg (*app, gint));
5029
5030 case 'd':
5031 return g_variant_new_double (va_arg (*app, gdouble));
5032
5033 default:
5034 g_assert_not_reached ();
5035 }
5036 }
5037
5038 /* The code below assumes this */
5039 G_STATIC_ASSERT (sizeof (gboolean) == sizeof (guint32));
5040 G_STATIC_ASSERT (sizeof (gdouble) == sizeof (guint64));
5041
5042 static void
g_variant_valist_get_leaf(const gchar ** str,GVariant * value,gboolean free,va_list * app)5043 g_variant_valist_get_leaf (const gchar **str,
5044 GVariant *value,
5045 gboolean free,
5046 va_list *app)
5047 {
5048 gpointer ptr = va_arg (*app, gpointer);
5049
5050 if (ptr == NULL)
5051 {
5052 g_variant_format_string_scan (*str, NULL, str);
5053 return;
5054 }
5055
5056 if (g_variant_format_string_is_nnp (*str))
5057 {
5058 gpointer *nnp = (gpointer *) ptr;
5059
5060 if (free && *nnp != NULL)
5061 g_variant_valist_free_nnp (*str, *nnp);
5062
5063 *nnp = NULL;
5064
5065 if (value != NULL)
5066 *nnp = g_variant_valist_get_nnp (str, value);
5067 else
5068 g_variant_format_string_scan (*str, NULL, str);
5069
5070 return;
5071 }
5072
5073 if (value != NULL)
5074 {
5075 switch (*(*str)++)
5076 {
5077 case 'b':
5078 *(gboolean *) ptr = g_variant_get_boolean (value);
5079 return;
5080
5081 case 'y':
5082 *(guint8 *) ptr = g_variant_get_byte (value);
5083 return;
5084
5085 case 'n':
5086 *(gint16 *) ptr = g_variant_get_int16 (value);
5087 return;
5088
5089 case 'q':
5090 *(guint16 *) ptr = g_variant_get_uint16 (value);
5091 return;
5092
5093 case 'i':
5094 *(gint32 *) ptr = g_variant_get_int32 (value);
5095 return;
5096
5097 case 'u':
5098 *(guint32 *) ptr = g_variant_get_uint32 (value);
5099 return;
5100
5101 case 'x':
5102 *(gint64 *) ptr = g_variant_get_int64 (value);
5103 return;
5104
5105 case 't':
5106 *(guint64 *) ptr = g_variant_get_uint64 (value);
5107 return;
5108
5109 case 'h':
5110 *(gint32 *) ptr = g_variant_get_handle (value);
5111 return;
5112
5113 case 'd':
5114 *(gdouble *) ptr = g_variant_get_double (value);
5115 return;
5116 }
5117 }
5118 else
5119 {
5120 switch (*(*str)++)
5121 {
5122 case 'y':
5123 *(guint8 *) ptr = 0;
5124 return;
5125
5126 case 'n':
5127 case 'q':
5128 *(guint16 *) ptr = 0;
5129 return;
5130
5131 case 'i':
5132 case 'u':
5133 case 'h':
5134 case 'b':
5135 *(guint32 *) ptr = 0;
5136 return;
5137
5138 case 'x':
5139 case 't':
5140 case 'd':
5141 *(guint64 *) ptr = 0;
5142 return;
5143 }
5144 }
5145
5146 g_assert_not_reached ();
5147 }
5148
5149 /* Generic (recursive) {{{2 */
5150 static void
g_variant_valist_skip(const gchar ** str,va_list * app)5151 g_variant_valist_skip (const gchar **str,
5152 va_list *app)
5153 {
5154 if (g_variant_format_string_is_leaf (*str))
5155 g_variant_valist_skip_leaf (str, app);
5156
5157 else if (**str == 'm') /* maybe */
5158 {
5159 (*str)++;
5160
5161 if (!g_variant_format_string_is_nnp (*str))
5162 va_arg (*app, gboolean);
5163
5164 g_variant_valist_skip (str, app);
5165 }
5166 else /* tuple, dictionary entry */
5167 {
5168 g_assert (**str == '(' || **str == '{');
5169 (*str)++;
5170 while (**str != ')' && **str != '}')
5171 g_variant_valist_skip (str, app);
5172 (*str)++;
5173 }
5174 }
5175
5176 static GVariant *
g_variant_valist_new(const gchar ** str,va_list * app)5177 g_variant_valist_new (const gchar **str,
5178 va_list *app)
5179 {
5180 if (g_variant_format_string_is_leaf (*str))
5181 return g_variant_valist_new_leaf (str, app);
5182
5183 if (**str == 'm') /* maybe */
5184 {
5185 GVariantType *type = NULL;
5186 GVariant *value = NULL;
5187
5188 (*str)++;
5189
5190 if (g_variant_format_string_is_nnp (*str))
5191 {
5192 gpointer nnp = va_arg (*app, gpointer);
5193
5194 if (nnp != NULL)
5195 value = g_variant_valist_new_nnp (str, nnp);
5196 else
5197 type = g_variant_format_string_scan_type (*str, NULL, str);
5198 }
5199 else
5200 {
5201 gboolean just = va_arg (*app, gboolean);
5202
5203 if (just)
5204 value = g_variant_valist_new (str, app);
5205 else
5206 {
5207 type = g_variant_format_string_scan_type (*str, NULL, NULL);
5208 g_variant_valist_skip (str, app);
5209 }
5210 }
5211
5212 value = g_variant_new_maybe (type, value);
5213
5214 if (type != NULL)
5215 g_variant_type_free (type);
5216
5217 return value;
5218 }
5219 else /* tuple, dictionary entry */
5220 {
5221 GVariantBuilder b;
5222
5223 if (**str == '(')
5224 g_variant_builder_init (&b, G_VARIANT_TYPE_TUPLE);
5225 else
5226 {
5227 g_assert (**str == '{');
5228 g_variant_builder_init (&b, G_VARIANT_TYPE_DICT_ENTRY);
5229 }
5230
5231 (*str)++; /* '(' */
5232 while (**str != ')' && **str != '}')
5233 g_variant_builder_add_value (&b, g_variant_valist_new (str, app));
5234 (*str)++; /* ')' */
5235
5236 return g_variant_builder_end (&b);
5237 }
5238 }
5239
5240 static void
g_variant_valist_get(const gchar ** str,GVariant * value,gboolean free,va_list * app)5241 g_variant_valist_get (const gchar **str,
5242 GVariant *value,
5243 gboolean free,
5244 va_list *app)
5245 {
5246 if (g_variant_format_string_is_leaf (*str))
5247 g_variant_valist_get_leaf (str, value, free, app);
5248
5249 else if (**str == 'm')
5250 {
5251 (*str)++;
5252
5253 if (value != NULL)
5254 value = g_variant_get_maybe (value);
5255
5256 if (!g_variant_format_string_is_nnp (*str))
5257 {
5258 gboolean *ptr = va_arg (*app, gboolean *);
5259
5260 if (ptr != NULL)
5261 *ptr = value != NULL;
5262 }
5263
5264 g_variant_valist_get (str, value, free, app);
5265
5266 if (value != NULL)
5267 g_variant_unref (value);
5268 }
5269
5270 else /* tuple, dictionary entry */
5271 {
5272 gint index = 0;
5273
5274 g_assert (**str == '(' || **str == '{');
5275
5276 (*str)++;
5277 while (**str != ')' && **str != '}')
5278 {
5279 if (value != NULL)
5280 {
5281 GVariant *child = g_variant_get_child_value (value, index++);
5282 g_variant_valist_get (str, child, free, app);
5283 g_variant_unref (child);
5284 }
5285 else
5286 g_variant_valist_get (str, NULL, free, app);
5287 }
5288 (*str)++;
5289 }
5290 }
5291
5292 /* User-facing API {{{2 */
5293 /**
5294 * g_variant_new: (skip)
5295 * @format_string: a #GVariant format string
5296 * @...: arguments, as per @format_string
5297 *
5298 * Creates a new #GVariant instance.
5299 *
5300 * Think of this function as an analogue to g_strdup_printf().
5301 *
5302 * The type of the created instance and the arguments that are expected
5303 * by this function are determined by @format_string. See the section on
5304 * [GVariant format strings][gvariant-format-strings]. Please note that
5305 * the syntax of the format string is very likely to be extended in the
5306 * future.
5307 *
5308 * The first character of the format string must not be '*' '?' '@' or
5309 * 'r'; in essence, a new #GVariant must always be constructed by this
5310 * function (and not merely passed through it unmodified).
5311 *
5312 * Note that the arguments must be of the correct width for their types
5313 * specified in @format_string. This can be achieved by casting them. See
5314 * the [GVariant varargs documentation][gvariant-varargs].
5315 *
5316 * |[<!-- language="C" -->
5317 * MyFlags some_flags = FLAG_ONE | FLAG_TWO;
5318 * const gchar *some_strings[] = { "a", "b", "c", NULL };
5319 * GVariant *new_variant;
5320 *
5321 * new_variant = g_variant_new ("(t^as)",
5322 * // This cast is required.
5323 * (guint64) some_flags,
5324 * some_strings);
5325 * ]|
5326 *
5327 * Returns: a new floating #GVariant instance
5328 *
5329 * Since: 2.24
5330 **/
5331 GVariant *
g_variant_new(const gchar * format_string,...)5332 g_variant_new (const gchar *format_string,
5333 ...)
5334 {
5335 GVariant *value;
5336 va_list ap;
5337
5338 g_return_val_if_fail (valid_format_string (format_string, TRUE, NULL) &&
5339 format_string[0] != '?' && format_string[0] != '@' &&
5340 format_string[0] != '*' && format_string[0] != 'r',
5341 NULL);
5342
5343 va_start (ap, format_string);
5344 value = g_variant_new_va (format_string, NULL, &ap);
5345 va_end (ap);
5346
5347 return value;
5348 }
5349
5350 /**
5351 * g_variant_new_va: (skip)
5352 * @format_string: a string that is prefixed with a format string
5353 * @endptr: (nullable) (default NULL): location to store the end pointer,
5354 * or %NULL
5355 * @app: a pointer to a #va_list
5356 *
5357 * This function is intended to be used by libraries based on
5358 * #GVariant that want to provide g_variant_new()-like functionality
5359 * to their users.
5360 *
5361 * The API is more general than g_variant_new() to allow a wider range
5362 * of possible uses.
5363 *
5364 * @format_string must still point to a valid format string, but it only
5365 * needs to be nul-terminated if @endptr is %NULL. If @endptr is
5366 * non-%NULL then it is updated to point to the first character past the
5367 * end of the format string.
5368 *
5369 * @app is a pointer to a #va_list. The arguments, according to
5370 * @format_string, are collected from this #va_list and the list is left
5371 * pointing to the argument following the last.
5372 *
5373 * Note that the arguments in @app must be of the correct width for their
5374 * types specified in @format_string when collected into the #va_list.
5375 * See the [GVariant varargs documentation][gvariant-varargs].
5376 *
5377 * These two generalisations allow mixing of multiple calls to
5378 * g_variant_new_va() and g_variant_get_va() within a single actual
5379 * varargs call by the user.
5380 *
5381 * The return value will be floating if it was a newly created GVariant
5382 * instance (for example, if the format string was "(ii)"). In the case
5383 * that the format_string was '*', '?', 'r', or a format starting with
5384 * '@' then the collected #GVariant pointer will be returned unmodified,
5385 * without adding any additional references.
5386 *
5387 * In order to behave correctly in all cases it is necessary for the
5388 * calling function to g_variant_ref_sink() the return result before
5389 * returning control to the user that originally provided the pointer.
5390 * At this point, the caller will have their own full reference to the
5391 * result. This can also be done by adding the result to a container,
5392 * or by passing it to another g_variant_new() call.
5393 *
5394 * Returns: a new, usually floating, #GVariant
5395 *
5396 * Since: 2.24
5397 **/
5398 GVariant *
g_variant_new_va(const gchar * format_string,const gchar ** endptr,va_list * app)5399 g_variant_new_va (const gchar *format_string,
5400 const gchar **endptr,
5401 va_list *app)
5402 {
5403 GVariant *value;
5404
5405 g_return_val_if_fail (valid_format_string (format_string, !endptr, NULL),
5406 NULL);
5407 g_return_val_if_fail (app != NULL, NULL);
5408
5409 value = g_variant_valist_new (&format_string, app);
5410
5411 if (endptr != NULL)
5412 *endptr = format_string;
5413
5414 return value;
5415 }
5416
5417 /**
5418 * g_variant_get: (skip)
5419 * @value: a #GVariant instance
5420 * @format_string: a #GVariant format string
5421 * @...: arguments, as per @format_string
5422 *
5423 * Deconstructs a #GVariant instance.
5424 *
5425 * Think of this function as an analogue to scanf().
5426 *
5427 * The arguments that are expected by this function are entirely
5428 * determined by @format_string. @format_string also restricts the
5429 * permissible types of @value. It is an error to give a value with
5430 * an incompatible type. See the section on
5431 * [GVariant format strings][gvariant-format-strings].
5432 * Please note that the syntax of the format string is very likely to be
5433 * extended in the future.
5434 *
5435 * @format_string determines the C types that are used for unpacking
5436 * the values and also determines if the values are copied or borrowed,
5437 * see the section on
5438 * [GVariant format strings][gvariant-format-strings-pointers].
5439 *
5440 * Since: 2.24
5441 **/
5442 void
g_variant_get(GVariant * value,const gchar * format_string,...)5443 g_variant_get (GVariant *value,
5444 const gchar *format_string,
5445 ...)
5446 {
5447 va_list ap;
5448
5449 g_return_if_fail (value != NULL);
5450 g_return_if_fail (valid_format_string (format_string, TRUE, value));
5451
5452 /* if any direct-pointer-access formats are in use, flatten first */
5453 if (strchr (format_string, '&'))
5454 g_variant_get_data (value);
5455
5456 va_start (ap, format_string);
5457 g_variant_get_va (value, format_string, NULL, &ap);
5458 va_end (ap);
5459 }
5460
5461 /**
5462 * g_variant_get_va: (skip)
5463 * @value: a #GVariant
5464 * @format_string: a string that is prefixed with a format string
5465 * @endptr: (nullable) (default NULL): location to store the end pointer,
5466 * or %NULL
5467 * @app: a pointer to a #va_list
5468 *
5469 * This function is intended to be used by libraries based on #GVariant
5470 * that want to provide g_variant_get()-like functionality to their
5471 * users.
5472 *
5473 * The API is more general than g_variant_get() to allow a wider range
5474 * of possible uses.
5475 *
5476 * @format_string must still point to a valid format string, but it only
5477 * need to be nul-terminated if @endptr is %NULL. If @endptr is
5478 * non-%NULL then it is updated to point to the first character past the
5479 * end of the format string.
5480 *
5481 * @app is a pointer to a #va_list. The arguments, according to
5482 * @format_string, are collected from this #va_list and the list is left
5483 * pointing to the argument following the last.
5484 *
5485 * These two generalisations allow mixing of multiple calls to
5486 * g_variant_new_va() and g_variant_get_va() within a single actual
5487 * varargs call by the user.
5488 *
5489 * @format_string determines the C types that are used for unpacking
5490 * the values and also determines if the values are copied or borrowed,
5491 * see the section on
5492 * [GVariant format strings][gvariant-format-strings-pointers].
5493 *
5494 * Since: 2.24
5495 **/
5496 void
g_variant_get_va(GVariant * value,const gchar * format_string,const gchar ** endptr,va_list * app)5497 g_variant_get_va (GVariant *value,
5498 const gchar *format_string,
5499 const gchar **endptr,
5500 va_list *app)
5501 {
5502 g_return_if_fail (valid_format_string (format_string, !endptr, value));
5503 g_return_if_fail (value != NULL);
5504 g_return_if_fail (app != NULL);
5505
5506 /* if any direct-pointer-access formats are in use, flatten first */
5507 if (strchr (format_string, '&'))
5508 g_variant_get_data (value);
5509
5510 g_variant_valist_get (&format_string, value, FALSE, app);
5511
5512 if (endptr != NULL)
5513 *endptr = format_string;
5514 }
5515
5516 /* Varargs-enabled Utility Functions {{{1 */
5517
5518 /**
5519 * g_variant_builder_add: (skip)
5520 * @builder: a #GVariantBuilder
5521 * @format_string: a #GVariant varargs format string
5522 * @...: arguments, as per @format_string
5523 *
5524 * Adds to a #GVariantBuilder.
5525 *
5526 * This call is a convenience wrapper that is exactly equivalent to
5527 * calling g_variant_new() followed by g_variant_builder_add_value().
5528 *
5529 * Note that the arguments must be of the correct width for their types
5530 * specified in @format_string. This can be achieved by casting them. See
5531 * the [GVariant varargs documentation][gvariant-varargs].
5532 *
5533 * This function might be used as follows:
5534 *
5535 * |[<!-- language="C" -->
5536 * GVariant *
5537 * make_pointless_dictionary (void)
5538 * {
5539 * GVariantBuilder builder;
5540 * int i;
5541 *
5542 * g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);
5543 * for (i = 0; i < 16; i++)
5544 * {
5545 * gchar buf[3];
5546 *
5547 * sprintf (buf, "%d", i);
5548 * g_variant_builder_add (&builder, "{is}", i, buf);
5549 * }
5550 *
5551 * return g_variant_builder_end (&builder);
5552 * }
5553 * ]|
5554 *
5555 * Since: 2.24
5556 */
5557 void
g_variant_builder_add(GVariantBuilder * builder,const gchar * format_string,...)5558 g_variant_builder_add (GVariantBuilder *builder,
5559 const gchar *format_string,
5560 ...)
5561 {
5562 GVariant *variant;
5563 va_list ap;
5564
5565 va_start (ap, format_string);
5566 variant = g_variant_new_va (format_string, NULL, &ap);
5567 va_end (ap);
5568
5569 g_variant_builder_add_value (builder, variant);
5570 }
5571
5572 /**
5573 * g_variant_get_child: (skip)
5574 * @value: a container #GVariant
5575 * @index_: the index of the child to deconstruct
5576 * @format_string: a #GVariant format string
5577 * @...: arguments, as per @format_string
5578 *
5579 * Reads a child item out of a container #GVariant instance and
5580 * deconstructs it according to @format_string. This call is
5581 * essentially a combination of g_variant_get_child_value() and
5582 * g_variant_get().
5583 *
5584 * @format_string determines the C types that are used for unpacking
5585 * the values and also determines if the values are copied or borrowed,
5586 * see the section on
5587 * [GVariant format strings][gvariant-format-strings-pointers].
5588 *
5589 * Since: 2.24
5590 **/
5591 void
g_variant_get_child(GVariant * value,gsize index_,const gchar * format_string,...)5592 g_variant_get_child (GVariant *value,
5593 gsize index_,
5594 const gchar *format_string,
5595 ...)
5596 {
5597 GVariant *child;
5598 va_list ap;
5599
5600 /* if any direct-pointer-access formats are in use, flatten first */
5601 if (strchr (format_string, '&'))
5602 g_variant_get_data (value);
5603
5604 child = g_variant_get_child_value (value, index_);
5605 g_return_if_fail (valid_format_string (format_string, TRUE, child));
5606
5607 va_start (ap, format_string);
5608 g_variant_get_va (child, format_string, NULL, &ap);
5609 va_end (ap);
5610
5611 g_variant_unref (child);
5612 }
5613
5614 /**
5615 * g_variant_iter_next: (skip)
5616 * @iter: a #GVariantIter
5617 * @format_string: a GVariant format string
5618 * @...: the arguments to unpack the value into
5619 *
5620 * Gets the next item in the container and unpacks it into the variable
5621 * argument list according to @format_string, returning %TRUE.
5622 *
5623 * If no more items remain then %FALSE is returned.
5624 *
5625 * All of the pointers given on the variable arguments list of this
5626 * function are assumed to point at uninitialised memory. It is the
5627 * responsibility of the caller to free all of the values returned by
5628 * the unpacking process.
5629 *
5630 * Here is an example for memory management with g_variant_iter_next():
5631 * |[<!-- language="C" -->
5632 * // Iterates a dictionary of type 'a{sv}'
5633 * void
5634 * iterate_dictionary (GVariant *dictionary)
5635 * {
5636 * GVariantIter iter;
5637 * GVariant *value;
5638 * gchar *key;
5639 *
5640 * g_variant_iter_init (&iter, dictionary);
5641 * while (g_variant_iter_next (&iter, "{sv}", &key, &value))
5642 * {
5643 * g_print ("Item '%s' has type '%s'\n", key,
5644 * g_variant_get_type_string (value));
5645 *
5646 * // must free data for ourselves
5647 * g_variant_unref (value);
5648 * g_free (key);
5649 * }
5650 * }
5651 * ]|
5652 *
5653 * For a solution that is likely to be more convenient to C programmers
5654 * when dealing with loops, see g_variant_iter_loop().
5655 *
5656 * @format_string determines the C types that are used for unpacking
5657 * the values and also determines if the values are copied or borrowed.
5658 *
5659 * See the section on
5660 * [GVariant format strings][gvariant-format-strings-pointers].
5661 *
5662 * Returns: %TRUE if a value was unpacked, or %FALSE if there as no value
5663 *
5664 * Since: 2.24
5665 **/
5666 gboolean
g_variant_iter_next(GVariantIter * iter,const gchar * format_string,...)5667 g_variant_iter_next (GVariantIter *iter,
5668 const gchar *format_string,
5669 ...)
5670 {
5671 GVariant *value;
5672
5673 value = g_variant_iter_next_value (iter);
5674
5675 g_return_val_if_fail (valid_format_string (format_string, TRUE, value),
5676 FALSE);
5677
5678 if (value != NULL)
5679 {
5680 va_list ap;
5681
5682 va_start (ap, format_string);
5683 g_variant_valist_get (&format_string, value, FALSE, &ap);
5684 va_end (ap);
5685
5686 g_variant_unref (value);
5687 }
5688
5689 return value != NULL;
5690 }
5691
5692 /**
5693 * g_variant_iter_loop: (skip)
5694 * @iter: a #GVariantIter
5695 * @format_string: a GVariant format string
5696 * @...: the arguments to unpack the value into
5697 *
5698 * Gets the next item in the container and unpacks it into the variable
5699 * argument list according to @format_string, returning %TRUE.
5700 *
5701 * If no more items remain then %FALSE is returned.
5702 *
5703 * On the first call to this function, the pointers appearing on the
5704 * variable argument list are assumed to point at uninitialised memory.
5705 * On the second and later calls, it is assumed that the same pointers
5706 * will be given and that they will point to the memory as set by the
5707 * previous call to this function. This allows the previous values to
5708 * be freed, as appropriate.
5709 *
5710 * This function is intended to be used with a while loop as
5711 * demonstrated in the following example. This function can only be
5712 * used when iterating over an array. It is only valid to call this
5713 * function with a string constant for the format string and the same
5714 * string constant must be used each time. Mixing calls to this
5715 * function and g_variant_iter_next() or g_variant_iter_next_value() on
5716 * the same iterator causes undefined behavior.
5717 *
5718 * If you break out of a such a while loop using g_variant_iter_loop() then
5719 * you must free or unreference all the unpacked values as you would with
5720 * g_variant_get(). Failure to do so will cause a memory leak.
5721 *
5722 * Here is an example for memory management with g_variant_iter_loop():
5723 * |[<!-- language="C" -->
5724 * // Iterates a dictionary of type 'a{sv}'
5725 * void
5726 * iterate_dictionary (GVariant *dictionary)
5727 * {
5728 * GVariantIter iter;
5729 * GVariant *value;
5730 * gchar *key;
5731 *
5732 * g_variant_iter_init (&iter, dictionary);
5733 * while (g_variant_iter_loop (&iter, "{sv}", &key, &value))
5734 * {
5735 * g_print ("Item '%s' has type '%s'\n", key,
5736 * g_variant_get_type_string (value));
5737 *
5738 * // no need to free 'key' and 'value' here
5739 * // unless breaking out of this loop
5740 * }
5741 * }
5742 * ]|
5743 *
5744 * For most cases you should use g_variant_iter_next().
5745 *
5746 * This function is really only useful when unpacking into #GVariant or
5747 * #GVariantIter in order to allow you to skip the call to
5748 * g_variant_unref() or g_variant_iter_free().
5749 *
5750 * For example, if you are only looping over simple integer and string
5751 * types, g_variant_iter_next() is definitely preferred. For string
5752 * types, use the '&' prefix to avoid allocating any memory at all (and
5753 * thereby avoiding the need to free anything as well).
5754 *
5755 * @format_string determines the C types that are used for unpacking
5756 * the values and also determines if the values are copied or borrowed.
5757 *
5758 * See the section on
5759 * [GVariant format strings][gvariant-format-strings-pointers].
5760 *
5761 * Returns: %TRUE if a value was unpacked, or %FALSE if there was no
5762 * value
5763 *
5764 * Since: 2.24
5765 **/
5766 gboolean
g_variant_iter_loop(GVariantIter * iter,const gchar * format_string,...)5767 g_variant_iter_loop (GVariantIter *iter,
5768 const gchar *format_string,
5769 ...)
5770 {
5771 gboolean first_time = GVSI(iter)->loop_format == NULL;
5772 GVariant *value;
5773 va_list ap;
5774
5775 g_return_val_if_fail (first_time ||
5776 format_string == GVSI(iter)->loop_format,
5777 FALSE);
5778
5779 if (first_time)
5780 {
5781 TYPE_CHECK (GVSI(iter)->value, G_VARIANT_TYPE_ARRAY, FALSE);
5782 GVSI(iter)->loop_format = format_string;
5783
5784 if (strchr (format_string, '&'))
5785 g_variant_get_data (GVSI(iter)->value);
5786 }
5787
5788 value = g_variant_iter_next_value (iter);
5789
5790 g_return_val_if_fail (!first_time ||
5791 valid_format_string (format_string, TRUE, value),
5792 FALSE);
5793
5794 va_start (ap, format_string);
5795 g_variant_valist_get (&format_string, value, !first_time, &ap);
5796 va_end (ap);
5797
5798 if (value != NULL)
5799 g_variant_unref (value);
5800
5801 return value != NULL;
5802 }
5803
5804 /* Serialized data {{{1 */
5805 static GVariant *
g_variant_deep_copy(GVariant * value)5806 g_variant_deep_copy (GVariant *value)
5807 {
5808 switch (g_variant_classify (value))
5809 {
5810 case G_VARIANT_CLASS_MAYBE:
5811 case G_VARIANT_CLASS_ARRAY:
5812 case G_VARIANT_CLASS_TUPLE:
5813 case G_VARIANT_CLASS_DICT_ENTRY:
5814 case G_VARIANT_CLASS_VARIANT:
5815 {
5816 GVariantBuilder builder;
5817 GVariantIter iter;
5818 GVariant *child;
5819
5820 g_variant_builder_init (&builder, g_variant_get_type (value));
5821 g_variant_iter_init (&iter, value);
5822
5823 while ((child = g_variant_iter_next_value (&iter)))
5824 {
5825 g_variant_builder_add_value (&builder, g_variant_deep_copy (child));
5826 g_variant_unref (child);
5827 }
5828
5829 return g_variant_builder_end (&builder);
5830 }
5831
5832 case G_VARIANT_CLASS_BOOLEAN:
5833 return g_variant_new_boolean (g_variant_get_boolean (value));
5834
5835 case G_VARIANT_CLASS_BYTE:
5836 return g_variant_new_byte (g_variant_get_byte (value));
5837
5838 case G_VARIANT_CLASS_INT16:
5839 return g_variant_new_int16 (g_variant_get_int16 (value));
5840
5841 case G_VARIANT_CLASS_UINT16:
5842 return g_variant_new_uint16 (g_variant_get_uint16 (value));
5843
5844 case G_VARIANT_CLASS_INT32:
5845 return g_variant_new_int32 (g_variant_get_int32 (value));
5846
5847 case G_VARIANT_CLASS_UINT32:
5848 return g_variant_new_uint32 (g_variant_get_uint32 (value));
5849
5850 case G_VARIANT_CLASS_INT64:
5851 return g_variant_new_int64 (g_variant_get_int64 (value));
5852
5853 case G_VARIANT_CLASS_UINT64:
5854 return g_variant_new_uint64 (g_variant_get_uint64 (value));
5855
5856 case G_VARIANT_CLASS_HANDLE:
5857 return g_variant_new_handle (g_variant_get_handle (value));
5858
5859 case G_VARIANT_CLASS_DOUBLE:
5860 return g_variant_new_double (g_variant_get_double (value));
5861
5862 case G_VARIANT_CLASS_STRING:
5863 return g_variant_new_string (g_variant_get_string (value, NULL));
5864
5865 case G_VARIANT_CLASS_OBJECT_PATH:
5866 return g_variant_new_object_path (g_variant_get_string (value, NULL));
5867
5868 case G_VARIANT_CLASS_SIGNATURE:
5869 return g_variant_new_signature (g_variant_get_string (value, NULL));
5870 }
5871
5872 g_assert_not_reached ();
5873 }
5874
5875 /**
5876 * g_variant_get_normal_form:
5877 * @value: a #GVariant
5878 *
5879 * Gets a #GVariant instance that has the same value as @value and is
5880 * trusted to be in normal form.
5881 *
5882 * If @value is already trusted to be in normal form then a new
5883 * reference to @value is returned.
5884 *
5885 * If @value is not already trusted, then it is scanned to check if it
5886 * is in normal form. If it is found to be in normal form then it is
5887 * marked as trusted and a new reference to it is returned.
5888 *
5889 * If @value is found not to be in normal form then a new trusted
5890 * #GVariant is created with the same value as @value.
5891 *
5892 * It makes sense to call this function if you've received #GVariant
5893 * data from untrusted sources and you want to ensure your serialized
5894 * output is definitely in normal form.
5895 *
5896 * If @value is already in normal form, a new reference will be returned
5897 * (which will be floating if @value is floating). If it is not in normal form,
5898 * the newly created #GVariant will be returned with a single non-floating
5899 * reference. Typically, g_variant_take_ref() should be called on the return
5900 * value from this function to guarantee ownership of a single non-floating
5901 * reference to it.
5902 *
5903 * Returns: (transfer full): a trusted #GVariant
5904 *
5905 * Since: 2.24
5906 **/
5907 GVariant *
g_variant_get_normal_form(GVariant * value)5908 g_variant_get_normal_form (GVariant *value)
5909 {
5910 GVariant *trusted;
5911
5912 if (g_variant_is_normal_form (value))
5913 return g_variant_ref (value);
5914
5915 trusted = g_variant_deep_copy (value);
5916 g_assert (g_variant_is_trusted (trusted));
5917
5918 return g_variant_ref_sink (trusted);
5919 }
5920
5921 /**
5922 * g_variant_byteswap:
5923 * @value: a #GVariant
5924 *
5925 * Performs a byteswapping operation on the contents of @value. The
5926 * result is that all multi-byte numeric data contained in @value is
5927 * byteswapped. That includes 16, 32, and 64bit signed and unsigned
5928 * integers as well as file handles and double precision floating point
5929 * values.
5930 *
5931 * This function is an identity mapping on any value that does not
5932 * contain multi-byte numeric data. That include strings, booleans,
5933 * bytes and containers containing only these things (recursively).
5934 *
5935 * The returned value is always in normal form and is marked as trusted.
5936 *
5937 * Returns: (transfer full): the byteswapped form of @value
5938 *
5939 * Since: 2.24
5940 **/
5941 GVariant *
g_variant_byteswap(GVariant * value)5942 g_variant_byteswap (GVariant *value)
5943 {
5944 GVariantTypeInfo *type_info;
5945 guint alignment;
5946 GVariant *new;
5947
5948 type_info = g_variant_get_type_info (value);
5949
5950 g_variant_type_info_query (type_info, &alignment, NULL);
5951
5952 if (alignment)
5953 /* (potentially) contains multi-byte numeric data */
5954 {
5955 GVariantSerialised serialised;
5956 GVariant *trusted;
5957 GBytes *bytes;
5958
5959 trusted = g_variant_get_normal_form (value);
5960 serialised.type_info = g_variant_get_type_info (trusted);
5961 serialised.size = g_variant_get_size (trusted);
5962 serialised.data = g_malloc (serialised.size);
5963 serialised.depth = g_variant_get_depth (trusted);
5964 g_variant_store (trusted, serialised.data);
5965 g_variant_unref (trusted);
5966
5967 g_variant_serialised_byteswap (serialised);
5968
5969 bytes = g_bytes_new_take (serialised.data, serialised.size);
5970 new = g_variant_new_from_bytes (g_variant_get_type (value), bytes, TRUE);
5971 g_bytes_unref (bytes);
5972 }
5973 else
5974 /* contains no multi-byte data */
5975 new = value;
5976
5977 return g_variant_ref_sink (new);
5978 }
5979
5980 /**
5981 * g_variant_new_from_data:
5982 * @type: a definite #GVariantType
5983 * @data: (array length=size) (element-type guint8): the serialized data
5984 * @size: the size of @data
5985 * @trusted: %TRUE if @data is definitely in normal form
5986 * @notify: (scope async): function to call when @data is no longer needed
5987 * @user_data: data for @notify
5988 *
5989 * Creates a new #GVariant instance from serialized data.
5990 *
5991 * @type is the type of #GVariant instance that will be constructed.
5992 * The interpretation of @data depends on knowing the type.
5993 *
5994 * @data is not modified by this function and must remain valid with an
5995 * unchanging value until such a time as @notify is called with
5996 * @user_data. If the contents of @data change before that time then
5997 * the result is undefined.
5998 *
5999 * If @data is trusted to be serialized data in normal form then
6000 * @trusted should be %TRUE. This applies to serialized data created
6001 * within this process or read from a trusted location on the disk (such
6002 * as a file installed in /usr/lib alongside your application). You
6003 * should set trusted to %FALSE if @data is read from the network, a
6004 * file in the user's home directory, etc.
6005 *
6006 * If @data was not stored in this machine's native endianness, any multi-byte
6007 * numeric values in the returned variant will also be in non-native
6008 * endianness. g_variant_byteswap() can be used to recover the original values.
6009 *
6010 * @notify will be called with @user_data when @data is no longer
6011 * needed. The exact time of this call is unspecified and might even be
6012 * before this function returns.
6013 *
6014 * Note: @data must be backed by memory that is aligned appropriately for the
6015 * @type being loaded. Otherwise this function will internally create a copy of
6016 * the memory (since GLib 2.60) or (in older versions) fail and exit the
6017 * process.
6018 *
6019 * Returns: (transfer none): a new floating #GVariant of type @type
6020 *
6021 * Since: 2.24
6022 **/
6023 GVariant *
g_variant_new_from_data(const GVariantType * type,gconstpointer data,gsize size,gboolean trusted,GDestroyNotify notify,gpointer user_data)6024 g_variant_new_from_data (const GVariantType *type,
6025 gconstpointer data,
6026 gsize size,
6027 gboolean trusted,
6028 GDestroyNotify notify,
6029 gpointer user_data)
6030 {
6031 GVariant *value;
6032 GBytes *bytes;
6033
6034 g_return_val_if_fail (g_variant_type_is_definite (type), NULL);
6035 g_return_val_if_fail (data != NULL || size == 0, NULL);
6036
6037 if (notify)
6038 bytes = g_bytes_new_with_free_func (data, size, notify, user_data);
6039 else
6040 bytes = g_bytes_new_static (data, size);
6041
6042 value = g_variant_new_from_bytes (type, bytes, trusted);
6043 g_bytes_unref (bytes);
6044
6045 return value;
6046 }
6047
6048 /* Epilogue {{{1 */
6049 /* vim:set foldmethod=marker: */
6050