2 * Copyright © 2007, 2008 Ryan Lortie
3 * Copyright © 2010 Codethink Limited
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the licence, or (at your option) any later version.
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.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 * Boston, MA 02111-1307, USA.
20 * Author: Ryan Lortie <desrt@desrt.ca>
27 #include <glib/gvariant-serialiser.h>
28 #include "gvariant-internal.h"
29 #include <glib/gvariant-core.h>
30 #include <glib/gtestutils.h>
31 #include <glib/gstrfuncs.h>
32 #include <glib/gslice.h>
33 #include <glib/ghash.h>
34 #include <glib/gmem.h>
42 * @short_description: strongly typed value datatype
43 * @see_also: GVariantType
45 * #GVariant is a variant datatype; it stores a value along with
46 * information about the type of that value. The range of possible
47 * values is determined by the type. The type system used by #GVariant
50 * #GVariant instances always have a type and a value (which are given
51 * at construction time). The type and value of a #GVariant instance
52 * can never change other than by the #GVariant itself being
53 * destroyed. A #GVariant cannot contain a pointer.
55 * #GVariant is reference counted using g_variant_ref() and
56 * g_variant_unref(). #GVariant also has floating reference counts --
57 * see g_variant_ref_sink().
59 * #GVariant is completely threadsafe. A #GVariant instance can be
60 * concurrently accessed in any way from any number of threads without
63 * #GVariant is heavily optimised for dealing with data in serialised
64 * form. It works particularly well with data located in memory-mapped
65 * files. It can perform nearly all deserialisation operations in a
66 * small constant time, usually touching only a single memory page.
67 * Serialised #GVariant data can also be sent over the network.
69 * #GVariant is largely compatible with D-Bus. Almost all types of
70 * #GVariant instances can be sent over D-Bus. See #GVariantType for
71 * exceptions. (However, #GVariant's serialisation format is not the same
72 * as the serialisation format of a D-Bus message body: use #GDBusMessage,
73 * in the gio library, for those.)
75 * For space-efficiency, the #GVariant serialisation format does not
76 * automatically include the variant's type or endianness, which must
77 * either be implied from context (such as knowledge that a particular
78 * file format always contains a little-endian %G_VARIANT_TYPE_VARIANT)
79 * or supplied out-of-band (for instance, a type and/or endianness
80 * indicator could be placed at the beginning of a file, network message
83 * A #GVariant's size is limited mainly by any lower level operating
84 * system constraints, such as the number of bits in #gsize. For
85 * example, it is reasonable to have a 2GB file mapped into memory
86 * with #GMappedFile, and call g_variant_new_from_data() on it.
88 * For convenience to C programmers, #GVariant features powerful
89 * varargs-based value construction and destruction. This feature is
90 * designed to be embedded in other libraries.
92 * There is a Python-inspired text language for describing #GVariant
93 * values. #GVariant includes a printer for this language and a parser
94 * with type inferencing.
97 * <title>Memory Use</title>
99 * #GVariant tries to be quite efficient with respect to memory use.
100 * This section gives a rough idea of how much memory is used by the
101 * current implementation. The information here is subject to change
105 * The memory allocated by #GVariant can be grouped into 4 broad
106 * purposes: memory for serialised data, memory for the type
107 * information cache, buffer management memory and memory for the
108 * #GVariant structure itself.
110 * <refsect3 id="gvariant-serialised-data-memory">
111 * <title>Serialised Data Memory</title>
113 * This is the memory that is used for storing GVariant data in
114 * serialised form. This is what would be sent over the network or
115 * what would end up on disk.
118 * The amount of memory required to store a boolean is 1 byte. 16,
119 * 32 and 64 bit integers and double precision floating point numbers
120 * use their "natural" size. Strings (including object path and
121 * signature strings) are stored with a nul terminator, and as such
122 * use the length of the string plus 1 byte.
125 * Maybe types use no space at all to represent the null value and
126 * use the same amount of space (sometimes plus one byte) as the
127 * equivalent non-maybe-typed value to represent the non-null case.
130 * Arrays use the amount of space required to store each of their
131 * members, concatenated. Additionally, if the items stored in an
132 * array are not of a fixed-size (ie: strings, other arrays, etc)
133 * then an additional framing offset is stored for each item. The
134 * size of this offset is either 1, 2 or 4 bytes depending on the
135 * overall size of the container. Additionally, extra padding bytes
136 * are added as required for alignment of child values.
139 * Tuples (including dictionary entries) use the amount of space
140 * required to store each of their members, concatenated, plus one
141 * framing offset (as per arrays) for each non-fixed-sized item in
142 * the tuple, except for the last one. Additionally, extra padding
143 * bytes are added as required for alignment of child values.
146 * Variants use the same amount of space as the item inside of the
147 * variant, plus 1 byte, plus the length of the type string for the
148 * item inside the variant.
151 * As an example, consider a dictionary mapping strings to variants.
152 * In the case that the dictionary is empty, 0 bytes are required for
156 * If we add an item "width" that maps to the int32 value of 500 then
157 * we will use 4 byte to store the int32 (so 6 for the variant
158 * containing it) and 6 bytes for the string. The variant must be
159 * aligned to 8 after the 6 bytes of the string, so that's 2 extra
160 * bytes. 6 (string) + 2 (padding) + 6 (variant) is 14 bytes used
161 * for the dictionary entry. An additional 1 byte is added to the
162 * array as a framing offset making a total of 15 bytes.
165 * If we add another entry, "title" that maps to a nullable string
166 * that happens to have a value of null, then we use 0 bytes for the
167 * null value (and 3 bytes for the variant to contain it along with
168 * its type string) plus 6 bytes for the string. Again, we need 2
169 * padding bytes. That makes a total of 6 + 2 + 3 = 11 bytes.
172 * We now require extra padding between the two items in the array.
173 * After the 14 bytes of the first item, that's 2 bytes required. We
174 * now require 2 framing offsets for an extra two bytes. 14 + 2 + 11
175 * + 2 = 29 bytes to encode the entire two-item dictionary.
179 * <title>Type Information Cache</title>
181 * For each GVariant type that currently exists in the program a type
182 * information structure is kept in the type information cache. The
183 * type information structure is required for rapid deserialisation.
186 * Continuing with the above example, if a #GVariant exists with the
187 * type "a{sv}" then a type information struct will exist for
188 * "a{sv}", "{sv}", "s", and "v". Multiple uses of the same type
189 * will share the same type information. Additionally, all
190 * single-digit types are stored in read-only static memory and do
191 * not contribute to the writable memory footprint of a program using
195 * Aside from the type information structures stored in read-only
196 * memory, there are two forms of type information. One is used for
197 * container types where there is a single element type: arrays and
198 * maybe types. The other is used for container types where there
199 * are multiple element types: tuples and dictionary entries.
202 * Array type info structures are 6 * sizeof (void *), plus the
203 * memory required to store the type string itself. This means that
204 * on 32bit systems, the cache entry for "a{sv}" would require 30
205 * bytes of memory (plus malloc overhead).
208 * Tuple type info structures are 6 * sizeof (void *), plus 4 *
209 * sizeof (void *) for each item in the tuple, plus the memory
210 * required to store the type string itself. A 2-item tuple, for
211 * example, would have a type information structure that consumed
212 * writable memory in the size of 14 * sizeof (void *) (plus type
213 * string) This means that on 32bit systems, the cache entry for
214 * "{sv}" would require 61 bytes of memory (plus malloc overhead).
217 * This means that in total, for our "a{sv}" example, 91 bytes of
218 * type information would be allocated.
221 * The type information cache, additionally, uses a #GHashTable to
222 * store and lookup the cached items and stores a pointer to this
223 * hash table in static storage. The hash table is freed when there
224 * are zero items in the type cache.
227 * Although these sizes may seem large it is important to remember
228 * that a program will probably only have a very small number of
229 * different types of values in it and that only one type information
230 * structure is required for many different values of the same type.
234 * <title>Buffer Management Memory</title>
236 * #GVariant uses an internal buffer management structure to deal
237 * with the various different possible sources of serialised data
238 * that it uses. The buffer is responsible for ensuring that the
239 * correct call is made when the data is no longer in use by
240 * #GVariant. This may involve a g_free() or a g_slice_free() or
241 * even g_mapped_file_unref().
244 * One buffer management structure is used for each chunk of
245 * serialised data. The size of the buffer management structure is 4
246 * * (void *). On 32bit systems, that's 16 bytes.
250 * <title>GVariant structure</title>
252 * The size of a #GVariant structure is 6 * (void *). On 32 bit
253 * systems, that's 24 bytes.
256 * #GVariant structures only exist if they are explicitly created
257 * with API calls. For example, if a #GVariant is constructed out of
258 * serialised 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
266 * If calls are made to start accessing the other values then
267 * #GVariant instances will exist for those values only for as long
268 * as they are in use (ie: until you call g_variant_unref()). The
269 * type information is shared. The serialised data and the buffer
270 * management structure for that serialised data is shared by the
275 * <title>Summary</title>
277 * To put the entire example together, for our dictionary mapping
278 * strings to variants (with two entries, as given above), we are
279 * using 91 bytes of memory for type information, 29 byes of memory
280 * for the serialised data, 16 bytes for buffer management and 24
281 * bytes for the #GVariant instance, or a total of 160 bytes, plus
282 * malloc overhead. If we were to use g_variant_get_child_value() to
283 * access the two dictionary entries, we would use an additional 48
284 * bytes. If we were to have other dictionaries of the same type, we
285 * would use more memory for the serialised data and buffer
286 * management for those dictionaries, but the type information would
293 /* definition of GVariant structure is in gvariant-core.c */
295 /* this is a g_return_val_if_fail() for making
296 * sure a (GVariant *) has the required type.
298 #define TYPE_CHECK(value, TYPE, val) \
299 if G_UNLIKELY (!g_variant_is_of_type (value, TYPE)) { \
300 g_return_if_fail_warning (G_LOG_DOMAIN, G_STRFUNC, \
301 "g_variant_is_of_type (" #value \
306 /* Numeric Type Constructor/Getters {{{1 */
308 * g_variant_new_from_trusted:
309 * @type: the #GVariantType
310 * @data: the data to use
311 * @size: the size of @data
313 * Constructs a new trusted #GVariant instance from the provided data.
314 * This is used to implement g_variant_new_* for all the basic types.
316 * Returns: a new floating #GVariant
319 g_variant_new_from_trusted (const GVariantType *type,
326 bytes = g_bytes_new (data, size);
327 value = g_variant_new_from_bytes (type, bytes, TRUE);
328 g_bytes_unref (bytes);
334 * g_variant_new_boolean:
335 * @value: a #gboolean value
337 * Creates a new boolean #GVariant instance -- either %TRUE or %FALSE.
339 * Returns: (transfer none): a floating reference to a new boolean #GVariant instance
344 g_variant_new_boolean (gboolean value)
348 return g_variant_new_from_trusted (G_VARIANT_TYPE_BOOLEAN, &v, 1);
352 * g_variant_get_boolean:
353 * @value: a boolean #GVariant instance
355 * Returns the boolean value of @value.
357 * It is an error to call this function with a @value of any type
358 * other than %G_VARIANT_TYPE_BOOLEAN.
360 * Returns: %TRUE or %FALSE
365 g_variant_get_boolean (GVariant *value)
369 TYPE_CHECK (value, G_VARIANT_TYPE_BOOLEAN, FALSE);
371 data = g_variant_get_data (value);
373 return data != NULL ? *data != 0 : FALSE;
376 /* the constructors and accessors for byte, int{16,32,64}, handles and
377 * doubles all look pretty much exactly the same, so we reduce
380 #define NUMERIC_TYPE(TYPE, type, ctype) \
381 GVariant *g_variant_new_##type (ctype value) { \
382 return g_variant_new_from_trusted (G_VARIANT_TYPE_##TYPE, \
383 &value, sizeof value); \
385 ctype g_variant_get_##type (GVariant *value) { \
387 TYPE_CHECK (value, G_VARIANT_TYPE_ ## TYPE, 0); \
388 data = g_variant_get_data (value); \
389 return data != NULL ? *data : 0; \
394 * g_variant_new_byte:
395 * @value: a #guint8 value
397 * Creates a new byte #GVariant instance.
399 * Returns: (transfer none): a floating reference to a new byte #GVariant instance
404 * g_variant_get_byte:
405 * @value: a byte #GVariant instance
407 * Returns the byte value of @value.
409 * It is an error to call this function with a @value of any type
410 * other than %G_VARIANT_TYPE_BYTE.
416 NUMERIC_TYPE (BYTE, byte, guchar)
419 * g_variant_new_int16:
420 * @value: a #gint16 value
422 * Creates a new int16 #GVariant instance.
424 * Returns: (transfer none): a floating reference to a new int16 #GVariant instance
429 * g_variant_get_int16:
430 * @value: a int16 #GVariant instance
432 * Returns the 16-bit signed integer value of @value.
434 * It is an error to call this function with a @value of any type
435 * other than %G_VARIANT_TYPE_INT16.
441 NUMERIC_TYPE (INT16, int16, gint16)
444 * g_variant_new_uint16:
445 * @value: a #guint16 value
447 * Creates a new uint16 #GVariant instance.
449 * Returns: (transfer none): a floating reference to a new uint16 #GVariant instance
454 * g_variant_get_uint16:
455 * @value: a uint16 #GVariant instance
457 * Returns the 16-bit unsigned integer value of @value.
459 * It is an error to call this function with a @value of any type
460 * other than %G_VARIANT_TYPE_UINT16.
462 * Returns: a #guint16
466 NUMERIC_TYPE (UINT16, uint16, guint16)
469 * g_variant_new_int32:
470 * @value: a #gint32 value
472 * Creates a new int32 #GVariant instance.
474 * Returns: (transfer none): a floating reference to a new int32 #GVariant instance
479 * g_variant_get_int32:
480 * @value: a int32 #GVariant instance
482 * Returns the 32-bit signed integer value of @value.
484 * It is an error to call this function with a @value of any type
485 * other than %G_VARIANT_TYPE_INT32.
491 NUMERIC_TYPE (INT32, int32, gint32)
494 * g_variant_new_uint32:
495 * @value: a #guint32 value
497 * Creates a new uint32 #GVariant instance.
499 * Returns: (transfer none): a floating reference to a new uint32 #GVariant instance
504 * g_variant_get_uint32:
505 * @value: a uint32 #GVariant instance
507 * Returns the 32-bit unsigned integer value of @value.
509 * It is an error to call this function with a @value of any type
510 * other than %G_VARIANT_TYPE_UINT32.
512 * Returns: a #guint32
516 NUMERIC_TYPE (UINT32, uint32, guint32)
519 * g_variant_new_int64:
520 * @value: a #gint64 value
522 * Creates a new int64 #GVariant instance.
524 * Returns: (transfer none): a floating reference to a new int64 #GVariant instance
529 * g_variant_get_int64:
530 * @value: a int64 #GVariant instance
532 * Returns the 64-bit signed integer value of @value.
534 * It is an error to call this function with a @value of any type
535 * other than %G_VARIANT_TYPE_INT64.
541 NUMERIC_TYPE (INT64, int64, gint64)
544 * g_variant_new_uint64:
545 * @value: a #guint64 value
547 * Creates a new uint64 #GVariant instance.
549 * Returns: (transfer none): a floating reference to a new uint64 #GVariant instance
554 * g_variant_get_uint64:
555 * @value: a uint64 #GVariant instance
557 * Returns the 64-bit unsigned integer value of @value.
559 * It is an error to call this function with a @value of any type
560 * other than %G_VARIANT_TYPE_UINT64.
562 * Returns: a #guint64
566 NUMERIC_TYPE (UINT64, uint64, guint64)
569 * g_variant_new_handle:
570 * @value: a #gint32 value
572 * Creates a new handle #GVariant instance.
574 * By convention, handles are indexes into an array of file descriptors
575 * that are sent alongside a D-Bus message. If you're not interacting
576 * with D-Bus, you probably don't need them.
578 * Returns: (transfer none): a floating reference to a new handle #GVariant instance
583 * g_variant_get_handle:
584 * @value: a handle #GVariant instance
586 * Returns the 32-bit signed integer value of @value.
588 * It is an error to call this function with a @value of any type other
589 * than %G_VARIANT_TYPE_HANDLE.
591 * By convention, handles are indexes into an array of file descriptors
592 * that are sent alongside a D-Bus message. If you're not interacting
593 * with D-Bus, you probably don't need them.
599 NUMERIC_TYPE (HANDLE, handle, gint32)
602 * g_variant_new_double:
603 * @value: a #gdouble floating point value
605 * Creates a new double #GVariant instance.
607 * Returns: (transfer none): a floating reference to a new double #GVariant instance
612 * g_variant_get_double:
613 * @value: a double #GVariant instance
615 * Returns the double precision floating point value of @value.
617 * It is an error to call this function with a @value of any type
618 * other than %G_VARIANT_TYPE_DOUBLE.
620 * Returns: a #gdouble
624 NUMERIC_TYPE (DOUBLE, double, gdouble)
626 /* Container type Constructor / Deconstructors {{{1 */
628 * g_variant_new_maybe:
629 * @child_type: (allow-none): the #GVariantType of the child, or %NULL
630 * @child: (allow-none): the child value, or %NULL
632 * Depending on if @child is %NULL, either wraps @child inside of a
633 * maybe container or creates a Nothing instance for the given @type.
635 * At least one of @child_type and @child must be non-%NULL.
636 * If @child_type is non-%NULL then it must be a definite type.
637 * If they are both non-%NULL then @child_type must be the type
640 * If @child is a floating reference (see g_variant_ref_sink()), the new
641 * instance takes ownership of @child.
643 * Returns: (transfer none): a floating reference to a new #GVariant maybe instance
648 g_variant_new_maybe (const GVariantType *child_type,
651 GVariantType *maybe_type;
654 g_return_val_if_fail (child_type == NULL || g_variant_type_is_definite
656 g_return_val_if_fail (child_type != NULL || child != NULL, NULL);
657 g_return_val_if_fail (child_type == NULL || child == NULL ||
658 g_variant_is_of_type (child, child_type),
661 if (child_type == NULL)
662 child_type = g_variant_get_type (child);
664 maybe_type = g_variant_type_new_maybe (child_type);
671 children = g_new (GVariant *, 1);
672 children[0] = g_variant_ref_sink (child);
673 trusted = g_variant_is_trusted (children[0]);
675 value = g_variant_new_from_children (maybe_type, children, 1, trusted);
678 value = g_variant_new_from_children (maybe_type, NULL, 0, TRUE);
680 g_variant_type_free (maybe_type);
686 * g_variant_get_maybe:
687 * @value: a maybe-typed value
689 * Given a maybe-typed #GVariant instance, extract its value. If the
690 * value is Nothing, then this function returns %NULL.
692 * Returns: (allow-none) (transfer full): the contents of @value, or %NULL
697 g_variant_get_maybe (GVariant *value)
699 TYPE_CHECK (value, G_VARIANT_TYPE_MAYBE, NULL);
701 if (g_variant_n_children (value))
702 return g_variant_get_child_value (value, 0);
708 * g_variant_new_variant: (constructor)
709 * @value: a #GVariant instance
711 * Boxes @value. The result is a #GVariant instance representing a
712 * variant containing the original value.
714 * If @child is a floating reference (see g_variant_ref_sink()), the new
715 * instance takes ownership of @child.
717 * Returns: (transfer none): a floating reference to a new variant #GVariant instance
722 g_variant_new_variant (GVariant *value)
724 g_return_val_if_fail (value != NULL, NULL);
726 g_variant_ref_sink (value);
728 return g_variant_new_from_children (G_VARIANT_TYPE_VARIANT,
729 g_memdup (&value, sizeof value),
730 1, g_variant_is_trusted (value));
734 * g_variant_get_variant:
735 * @value: a variant #GVariant instance
737 * Unboxes @value. The result is the #GVariant instance that was
738 * contained in @value.
740 * Returns: (transfer full): the item contained in the variant
745 g_variant_get_variant (GVariant *value)
747 TYPE_CHECK (value, G_VARIANT_TYPE_VARIANT, NULL);
749 return g_variant_get_child_value (value, 0);
753 * g_variant_new_array:
754 * @child_type: (allow-none): the element type of the new array
755 * @children: (allow-none) (array length=n_children): an array of
756 * #GVariant pointers, the children
757 * @n_children: the length of @children
759 * Creates a new #GVariant array from @children.
761 * @child_type must be non-%NULL if @n_children is zero. Otherwise, the
762 * child type is determined by inspecting the first element of the
763 * @children array. If @child_type is non-%NULL then it must be a
766 * The items of the array are taken from the @children array. No entry
767 * in the @children array may be %NULL.
769 * All items in the array must have the same type, which must be the
770 * same as @child_type, if given.
772 * If the @children are floating references (see g_variant_ref_sink()), the
773 * new instance takes ownership of them as if via g_variant_ref_sink().
775 * Returns: (transfer none): a floating reference to a new #GVariant array
780 g_variant_new_array (const GVariantType *child_type,
781 GVariant * const *children,
784 GVariantType *array_type;
785 GVariant **my_children;
790 g_return_val_if_fail (n_children > 0 || child_type != NULL, NULL);
791 g_return_val_if_fail (n_children == 0 || children != NULL, NULL);
792 g_return_val_if_fail (child_type == NULL ||
793 g_variant_type_is_definite (child_type), NULL);
795 my_children = g_new (GVariant *, n_children);
798 if (child_type == NULL)
799 child_type = g_variant_get_type (children[0]);
800 array_type = g_variant_type_new_array (child_type);
802 for (i = 0; i < n_children; i++)
804 TYPE_CHECK (children[i], child_type, NULL);
805 my_children[i] = g_variant_ref_sink (children[i]);
806 trusted &= g_variant_is_trusted (children[i]);
809 value = g_variant_new_from_children (array_type, my_children,
810 n_children, trusted);
811 g_variant_type_free (array_type);
817 * g_variant_make_tuple_type:
818 * @children: (array length=n_children): an array of GVariant *
819 * @n_children: the length of @children
821 * Return the type of a tuple containing @children as its items.
823 static GVariantType *
824 g_variant_make_tuple_type (GVariant * const *children,
827 const GVariantType **types;
831 types = g_new (const GVariantType *, n_children);
833 for (i = 0; i < n_children; i++)
834 types[i] = g_variant_get_type (children[i]);
836 type = g_variant_type_new_tuple (types, n_children);
843 * g_variant_new_tuple:
844 * @children: (array length=n_children): the items to make the tuple out of
845 * @n_children: the length of @children
847 * Creates a new tuple #GVariant out of the items in @children. The
848 * type is determined from the types of @children. No entry in the
849 * @children array may be %NULL.
851 * If @n_children is 0 then the unit tuple is constructed.
853 * If the @children are floating references (see g_variant_ref_sink()), the
854 * new instance takes ownership of them as if via g_variant_ref_sink().
856 * Returns: (transfer none): a floating reference to a new #GVariant tuple
861 g_variant_new_tuple (GVariant * const *children,
864 GVariantType *tuple_type;
865 GVariant **my_children;
870 g_return_val_if_fail (n_children == 0 || children != NULL, NULL);
872 my_children = g_new (GVariant *, n_children);
875 for (i = 0; i < n_children; i++)
877 my_children[i] = g_variant_ref_sink (children[i]);
878 trusted &= g_variant_is_trusted (children[i]);
881 tuple_type = g_variant_make_tuple_type (children, n_children);
882 value = g_variant_new_from_children (tuple_type, my_children,
883 n_children, trusted);
884 g_variant_type_free (tuple_type);
890 * g_variant_make_dict_entry_type:
891 * @key: a #GVariant, the key
892 * @val: a #GVariant, the value
894 * Return the type of a dictionary entry containing @key and @val as its
897 static GVariantType *
898 g_variant_make_dict_entry_type (GVariant *key,
901 return g_variant_type_new_dict_entry (g_variant_get_type (key),
902 g_variant_get_type (val));
906 * g_variant_new_dict_entry: (constructor)
907 * @key: a basic #GVariant, the key
908 * @value: a #GVariant, the value
910 * Creates a new dictionary entry #GVariant. @key and @value must be
911 * non-%NULL. @key must be a value of a basic type (ie: not a container).
913 * If the @key or @value are floating references (see g_variant_ref_sink()),
914 * the new instance takes ownership of them as if via g_variant_ref_sink().
916 * Returns: (transfer none): a floating reference to a new dictionary entry #GVariant
921 g_variant_new_dict_entry (GVariant *key,
924 GVariantType *dict_type;
928 g_return_val_if_fail (key != NULL && value != NULL, NULL);
929 g_return_val_if_fail (!g_variant_is_container (key), NULL);
931 children = g_new (GVariant *, 2);
932 children[0] = g_variant_ref_sink (key);
933 children[1] = g_variant_ref_sink (value);
934 trusted = g_variant_is_trusted (key) && g_variant_is_trusted (value);
936 dict_type = g_variant_make_dict_entry_type (key, value);
937 value = g_variant_new_from_children (dict_type, children, 2, trusted);
938 g_variant_type_free (dict_type);
944 * g_variant_lookup: (skip)
945 * @dictionary: a dictionary #GVariant
946 * @key: the key to lookup in the dictionary
947 * @format_string: a GVariant format string
948 * @...: the arguments to unpack the value into
950 * Looks up a value in a dictionary #GVariant.
952 * This function is a wrapper around g_variant_lookup_value() and
953 * g_variant_get(). In the case that %NULL would have been returned,
954 * this function returns %FALSE. Otherwise, it unpacks the returned
955 * value and returns %TRUE.
957 * @format_string determines the C types that are used for unpacking
958 * the values and also determines if the values are copied or borrowed,
960 * <link linkend='gvariant-format-strings-pointers'>GVariant Format Strings</link>.
962 * Returns: %TRUE if a value was unpacked
967 g_variant_lookup (GVariant *dictionary,
969 const gchar *format_string,
976 g_variant_get_data (dictionary);
978 type = g_variant_format_string_scan_type (format_string, NULL, NULL);
979 value = g_variant_lookup_value (dictionary, key, type);
980 g_variant_type_free (type);
986 va_start (ap, format_string);
987 g_variant_get_va (value, format_string, NULL, &ap);
988 g_variant_unref (value);
999 * g_variant_lookup_value:
1000 * @dictionary: a dictionary #GVariant
1001 * @key: the key to lookup in the dictionary
1002 * @expected_type: (allow-none): a #GVariantType, or %NULL
1004 * Looks up a value in a dictionary #GVariant.
1006 * This function works with dictionaries of the type
1007 * <literal>a{s*}</literal> (and equally well with type
1008 * <literal>a{o*}</literal>, but we only further discuss the string case
1009 * for sake of clarity).
1011 * In the event that @dictionary has the type <literal>a{sv}</literal>,
1012 * the @expected_type string specifies what type of value is expected to
1013 * be inside of the variant. If the value inside the variant has a
1014 * different type then %NULL is returned. In the event that @dictionary
1015 * has a value type other than <literal>v</literal> then @expected_type
1016 * must directly match the key type and it is used to unpack the value
1017 * directly or an error occurs.
1019 * In either case, if @key is not found in @dictionary, %NULL is
1022 * If the key is found and the value has the correct type, it is
1023 * returned. If @expected_type was specified then any non-%NULL return
1024 * value will have this type.
1026 * Returns: (transfer full): the value of the dictionary key, or %NULL
1031 g_variant_lookup_value (GVariant *dictionary,
1033 const GVariantType *expected_type)
1039 g_return_val_if_fail (g_variant_is_of_type (dictionary,
1040 G_VARIANT_TYPE ("a{s*}")) ||
1041 g_variant_is_of_type (dictionary,
1042 G_VARIANT_TYPE ("a{o*}")),
1045 g_variant_iter_init (&iter, dictionary);
1047 while ((entry = g_variant_iter_next_value (&iter)))
1049 GVariant *entry_key;
1052 entry_key = g_variant_get_child_value (entry, 0);
1053 matches = strcmp (g_variant_get_string (entry_key, NULL), key) == 0;
1054 g_variant_unref (entry_key);
1059 g_variant_unref (entry);
1065 value = g_variant_get_child_value (entry, 1);
1066 g_variant_unref (entry);
1068 if (g_variant_is_of_type (value, G_VARIANT_TYPE_VARIANT))
1072 tmp = g_variant_get_variant (value);
1073 g_variant_unref (value);
1075 if (expected_type && !g_variant_is_of_type (tmp, expected_type))
1077 g_variant_unref (tmp);
1084 g_return_val_if_fail (expected_type == NULL || value == NULL ||
1085 g_variant_is_of_type (value, expected_type), NULL);
1091 * g_variant_get_fixed_array:
1092 * @value: a #GVariant array with fixed-sized elements
1093 * @n_elements: (out): a pointer to the location to store the number of items
1094 * @element_size: the size of each element
1096 * Provides access to the serialised data for an array of fixed-sized
1099 * @value must be an array with fixed-sized elements. Numeric types are
1100 * fixed-size, as are tuples containing only other fixed-sized types.
1102 * @element_size must be the size of a single element in the array,
1103 * as given by the section on
1104 * <link linkend='gvariant-serialised-data-memory'>Serialised Data
1107 * In particular, arrays of these fixed-sized types can be interpreted
1108 * as an array of the given C type, with @element_size set to
1109 * <code>sizeof</code> the appropriate type:
1113 * <thead><row><entry>element type</entry> <entry>C type</entry></row></thead>
1115 * <row><entry>%G_VARIANT_TYPE_INT16 (etc.)</entry>
1116 * <entry>#gint16 (etc.)</entry></row>
1117 * <row><entry>%G_VARIANT_TYPE_BOOLEAN</entry>
1118 * <entry>#guchar (not #gboolean!)</entry></row>
1119 * <row><entry>%G_VARIANT_TYPE_BYTE</entry> <entry>#guchar</entry></row>
1120 * <row><entry>%G_VARIANT_TYPE_HANDLE</entry> <entry>#guint32</entry></row>
1121 * <row><entry>%G_VARIANT_TYPE_DOUBLE</entry> <entry>#gdouble</entry></row>
1126 * For example, if calling this function for an array of 32 bit integers,
1127 * you might say <code>sizeof (gint32)</code>. This value isn't used
1128 * except for the purpose of a double-check that the form of the
1129 * serialised data matches the caller's expectation.
1131 * @n_elements, which must be non-%NULL is set equal to the number of
1132 * items in the array.
1134 * Returns: (array length=n_elements) (transfer none): a pointer to
1140 g_variant_get_fixed_array (GVariant *value,
1144 GVariantTypeInfo *array_info;
1145 gsize array_element_size;
1149 TYPE_CHECK (value, G_VARIANT_TYPE_ARRAY, NULL);
1151 g_return_val_if_fail (n_elements != NULL, NULL);
1152 g_return_val_if_fail (element_size > 0, NULL);
1154 array_info = g_variant_get_type_info (value);
1155 g_variant_type_info_query_element (array_info, NULL, &array_element_size);
1157 g_return_val_if_fail (array_element_size, NULL);
1159 if G_UNLIKELY (array_element_size != element_size)
1161 if (array_element_size)
1162 g_critical ("g_variant_get_fixed_array: assertion "
1163 "`g_variant_array_has_fixed_size (value, element_size)' "
1164 "failed: array size %"G_GSIZE_FORMAT" does not match "
1165 "given element_size %"G_GSIZE_FORMAT".",
1166 array_element_size, element_size);
1168 g_critical ("g_variant_get_fixed_array: assertion "
1169 "`g_variant_array_has_fixed_size (value, element_size)' "
1170 "failed: array does not have fixed size.");
1173 data = g_variant_get_data (value);
1174 size = g_variant_get_size (value);
1176 if (size % element_size)
1179 *n_elements = size / element_size;
1188 * g_variant_new_fixed_array:
1189 * @element_type: the #GVariantType of each element
1190 * @elements: a pointer to the fixed array of contiguous elements
1191 * @n_elements: the number of elements
1192 * @element_size: the size of each element
1194 * Provides access to the serialised data for an array of fixed-sized
1197 * @value must be an array with fixed-sized elements. Numeric types are
1198 * fixed-size as are tuples containing only other fixed-sized types.
1200 * @element_size must be the size of a single element in the array. For
1201 * example, if calling this function for an array of 32 bit integers,
1202 * you might say <code>sizeof (gint32)</code>. This value isn't used
1203 * except for the purpose of a double-check that the form of the
1204 * serialised data matches the caller's expectation.
1206 * @n_elements, which must be non-%NULL is set equal to the number of
1207 * items in the array.
1209 * Returns: (transfer none): a floating reference to a new array #GVariant instance
1214 g_variant_new_fixed_array (const GVariantType *element_type,
1215 gconstpointer elements,
1219 GVariantType *array_type;
1220 gsize array_element_size;
1221 GVariantTypeInfo *array_info;
1225 g_return_val_if_fail (g_variant_type_is_definite (element_type), NULL);
1226 g_return_val_if_fail (element_size > 0, NULL);
1228 array_type = g_variant_type_new_array (element_type);
1229 array_info = g_variant_type_info_get (array_type);
1230 g_variant_type_info_query_element (array_info, NULL, &array_element_size);
1231 if G_UNLIKELY (array_element_size != element_size)
1233 if (array_element_size)
1234 g_critical ("g_variant_new_fixed_array: array size %" G_GSIZE_FORMAT
1235 " does not match given element_size %" G_GSIZE_FORMAT ".",
1236 array_element_size, element_size);
1238 g_critical ("g_variant_get_fixed_array: array does not have fixed size.");
1242 data = g_memdup (elements, n_elements * element_size);
1243 value = g_variant_new_from_data (array_type, data,
1244 n_elements * element_size,
1245 FALSE, g_free, data);
1247 g_variant_type_free (array_type);
1248 g_variant_type_info_unref (array_info);
1253 /* String type constructor/getters/validation {{{1 */
1255 * g_variant_new_string:
1256 * @string: a normal utf8 nul-terminated string
1258 * Creates a string #GVariant with the contents of @string.
1260 * @string must be valid utf8.
1262 * Returns: (transfer none): a floating reference to a new string #GVariant instance
1267 g_variant_new_string (const gchar *string)
1269 g_return_val_if_fail (string != NULL, NULL);
1270 g_return_val_if_fail (g_utf8_validate (string, -1, NULL), NULL);
1272 return g_variant_new_from_trusted (G_VARIANT_TYPE_STRING,
1273 string, strlen (string) + 1);
1277 * g_variant_new_object_path:
1278 * @object_path: a normal C nul-terminated string
1280 * Creates a D-Bus object path #GVariant with the contents of @string.
1281 * @string must be a valid D-Bus object path. Use
1282 * g_variant_is_object_path() if you're not sure.
1284 * Returns: (transfer none): a floating reference to a new object path #GVariant instance
1289 g_variant_new_object_path (const gchar *object_path)
1291 g_return_val_if_fail (g_variant_is_object_path (object_path), NULL);
1293 return g_variant_new_from_trusted (G_VARIANT_TYPE_OBJECT_PATH,
1294 object_path, strlen (object_path) + 1);
1298 * g_variant_is_object_path:
1299 * @string: a normal C nul-terminated string
1301 * Determines if a given string is a valid D-Bus object path. You
1302 * should ensure that a string is a valid D-Bus object path before
1303 * passing it to g_variant_new_object_path().
1305 * A valid object path starts with '/' followed by zero or more
1306 * sequences of characters separated by '/' characters. Each sequence
1307 * must contain only the characters "[A-Z][a-z][0-9]_". No sequence
1308 * (including the one following the final '/' character) may be empty.
1310 * Returns: %TRUE if @string is a D-Bus object path
1315 g_variant_is_object_path (const gchar *string)
1317 g_return_val_if_fail (string != NULL, FALSE);
1319 return g_variant_serialiser_is_object_path (string, strlen (string) + 1);
1323 * g_variant_new_signature:
1324 * @signature: a normal C nul-terminated string
1326 * Creates a D-Bus type signature #GVariant with the contents of
1327 * @string. @string must be a valid D-Bus type signature. Use
1328 * g_variant_is_signature() if you're not sure.
1330 * Returns: (transfer none): a floating reference to a new signature #GVariant instance
1335 g_variant_new_signature (const gchar *signature)
1337 g_return_val_if_fail (g_variant_is_signature (signature), NULL);
1339 return g_variant_new_from_trusted (G_VARIANT_TYPE_SIGNATURE,
1340 signature, strlen (signature) + 1);
1344 * g_variant_is_signature:
1345 * @string: a normal C nul-terminated string
1347 * Determines if a given string is a valid D-Bus type signature. You
1348 * should ensure that a string is a valid D-Bus type signature before
1349 * passing it to g_variant_new_signature().
1351 * D-Bus type signatures consist of zero or more definite #GVariantType
1352 * strings in sequence.
1354 * Returns: %TRUE if @string is a D-Bus type signature
1359 g_variant_is_signature (const gchar *string)
1361 g_return_val_if_fail (string != NULL, FALSE);
1363 return g_variant_serialiser_is_signature (string, strlen (string) + 1);
1367 * g_variant_get_string:
1368 * @value: a string #GVariant instance
1369 * @length: (allow-none) (default 0) (out): a pointer to a #gsize,
1370 * to store the length
1372 * Returns the string value of a #GVariant instance with a string
1373 * type. This includes the types %G_VARIANT_TYPE_STRING,
1374 * %G_VARIANT_TYPE_OBJECT_PATH and %G_VARIANT_TYPE_SIGNATURE.
1376 * The string will always be utf8 encoded.
1378 * If @length is non-%NULL then the length of the string (in bytes) is
1379 * returned there. For trusted values, this information is already
1380 * known. For untrusted values, a strlen() will be performed.
1382 * It is an error to call this function with a @value of any type
1383 * other than those three.
1385 * The return value remains valid as long as @value exists.
1387 * Returns: (transfer none): the constant string, utf8 encoded
1392 g_variant_get_string (GVariant *value,
1398 g_return_val_if_fail (value != NULL, NULL);
1399 g_return_val_if_fail (
1400 g_variant_is_of_type (value, G_VARIANT_TYPE_STRING) ||
1401 g_variant_is_of_type (value, G_VARIANT_TYPE_OBJECT_PATH) ||
1402 g_variant_is_of_type (value, G_VARIANT_TYPE_SIGNATURE), NULL);
1404 data = g_variant_get_data (value);
1405 size = g_variant_get_size (value);
1407 if (!g_variant_is_trusted (value))
1409 switch (g_variant_classify (value))
1411 case G_VARIANT_CLASS_STRING:
1412 if (g_variant_serialiser_is_string (data, size))
1419 case G_VARIANT_CLASS_OBJECT_PATH:
1420 if (g_variant_serialiser_is_object_path (data, size))
1427 case G_VARIANT_CLASS_SIGNATURE:
1428 if (g_variant_serialiser_is_signature (data, size))
1436 g_assert_not_reached ();
1447 * g_variant_dup_string:
1448 * @value: a string #GVariant instance
1449 * @length: (out): a pointer to a #gsize, to store the length
1451 * Similar to g_variant_get_string() except that instead of returning
1452 * a constant string, the string is duplicated.
1454 * The string will always be utf8 encoded.
1456 * The return value must be freed using g_free().
1458 * Returns: (transfer full): a newly allocated string, utf8 encoded
1463 g_variant_dup_string (GVariant *value,
1466 return g_strdup (g_variant_get_string (value, length));
1470 * g_variant_new_strv:
1471 * @strv: (array length=length) (element-type utf8): an array of strings
1472 * @length: the length of @strv, or -1
1474 * Constructs an array of strings #GVariant from the given array of
1477 * If @length is -1 then @strv is %NULL-terminated.
1479 * Returns: (transfer none): a new floating #GVariant instance
1484 g_variant_new_strv (const gchar * const *strv,
1490 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1493 length = g_strv_length ((gchar **) strv);
1495 strings = g_new (GVariant *, length);
1496 for (i = 0; i < length; i++)
1497 strings[i] = g_variant_ref_sink (g_variant_new_string (strv[i]));
1499 return g_variant_new_from_children (G_VARIANT_TYPE_STRING_ARRAY,
1500 strings, length, TRUE);
1504 * g_variant_get_strv:
1505 * @value: an array of strings #GVariant
1506 * @length: (out) (allow-none): the length of the result, or %NULL
1508 * Gets the contents of an array of strings #GVariant. This call
1509 * makes a shallow copy; the return result should be released with
1510 * g_free(), but the individual strings must not be modified.
1512 * If @length is non-%NULL then the number of elements in the result
1513 * is stored there. In any case, the resulting array will be
1516 * For an empty array, @length will be set to 0 and a pointer to a
1517 * %NULL pointer will be returned.
1519 * Returns: (array length=length zero-terminated=1) (transfer container): an array of constant strings
1524 g_variant_get_strv (GVariant *value,
1531 TYPE_CHECK (value, G_VARIANT_TYPE_STRING_ARRAY, NULL);
1533 g_variant_get_data (value);
1534 n = g_variant_n_children (value);
1535 strv = g_new (const gchar *, n + 1);
1537 for (i = 0; i < n; i++)
1541 string = g_variant_get_child_value (value, i);
1542 strv[i] = g_variant_get_string (string, NULL);
1543 g_variant_unref (string);
1554 * g_variant_dup_strv:
1555 * @value: an array of strings #GVariant
1556 * @length: (out) (allow-none): the length of the result, or %NULL
1558 * Gets the contents of an array of strings #GVariant. This call
1559 * makes a deep copy; the return result should be released with
1562 * If @length is non-%NULL then the number of elements in the result
1563 * is stored there. In any case, the resulting array will be
1566 * For an empty array, @length will be set to 0 and a pointer to a
1567 * %NULL pointer will be returned.
1569 * Returns: (array length=length zero-terminated=1) (transfer full): an array of strings
1574 g_variant_dup_strv (GVariant *value,
1581 TYPE_CHECK (value, G_VARIANT_TYPE_STRING_ARRAY, NULL);
1583 n = g_variant_n_children (value);
1584 strv = g_new (gchar *, n + 1);
1586 for (i = 0; i < n; i++)
1590 string = g_variant_get_child_value (value, i);
1591 strv[i] = g_variant_dup_string (string, NULL);
1592 g_variant_unref (string);
1603 * g_variant_new_objv:
1604 * @strv: (array length=length) (element-type utf8): an array of strings
1605 * @length: the length of @strv, or -1
1607 * Constructs an array of object paths #GVariant from the given array of
1610 * Each string must be a valid #GVariant object path; see
1611 * g_variant_is_object_path().
1613 * If @length is -1 then @strv is %NULL-terminated.
1615 * Returns: (transfer none): a new floating #GVariant instance
1620 g_variant_new_objv (const gchar * const *strv,
1626 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1629 length = g_strv_length ((gchar **) strv);
1631 strings = g_new (GVariant *, length);
1632 for (i = 0; i < length; i++)
1633 strings[i] = g_variant_ref_sink (g_variant_new_object_path (strv[i]));
1635 return g_variant_new_from_children (G_VARIANT_TYPE_OBJECT_PATH_ARRAY,
1636 strings, length, TRUE);
1640 * g_variant_get_objv:
1641 * @value: an array of object paths #GVariant
1642 * @length: (out) (allow-none): the length of the result, or %NULL
1644 * Gets the contents of an array of object paths #GVariant. This call
1645 * makes a shallow copy; the return result should be released with
1646 * g_free(), but the individual strings must not be modified.
1648 * If @length is non-%NULL then the number of elements in the result
1649 * is stored there. In any case, the resulting array will be
1652 * For an empty array, @length will be set to 0 and a pointer to a
1653 * %NULL pointer will be returned.
1655 * Returns: (array length=length zero-terminated=1) (transfer container): an array of constant strings
1660 g_variant_get_objv (GVariant *value,
1667 TYPE_CHECK (value, G_VARIANT_TYPE_OBJECT_PATH_ARRAY, NULL);
1669 g_variant_get_data (value);
1670 n = g_variant_n_children (value);
1671 strv = g_new (const gchar *, n + 1);
1673 for (i = 0; i < n; i++)
1677 string = g_variant_get_child_value (value, i);
1678 strv[i] = g_variant_get_string (string, NULL);
1679 g_variant_unref (string);
1690 * g_variant_dup_objv:
1691 * @value: an array of object paths #GVariant
1692 * @length: (out) (allow-none): the length of the result, or %NULL
1694 * Gets the contents of an array of object paths #GVariant. This call
1695 * makes a deep copy; the return result should be released with
1698 * If @length is non-%NULL then the number of elements in the result
1699 * is stored there. In any case, the resulting array will be
1702 * For an empty array, @length will be set to 0 and a pointer to a
1703 * %NULL pointer will be returned.
1705 * Returns: (array length=length zero-terminated=1) (transfer full): an array of strings
1710 g_variant_dup_objv (GVariant *value,
1717 TYPE_CHECK (value, G_VARIANT_TYPE_OBJECT_PATH_ARRAY, NULL);
1719 n = g_variant_n_children (value);
1720 strv = g_new (gchar *, n + 1);
1722 for (i = 0; i < n; i++)
1726 string = g_variant_get_child_value (value, i);
1727 strv[i] = g_variant_dup_string (string, NULL);
1728 g_variant_unref (string);
1740 * g_variant_new_bytestring:
1741 * @string: (array zero-terminated=1) (element-type guint8): a normal
1742 * nul-terminated string in no particular encoding
1744 * Creates an array-of-bytes #GVariant with the contents of @string.
1745 * This function is just like g_variant_new_string() except that the
1746 * string need not be valid utf8.
1748 * The nul terminator character at the end of the string is stored in
1751 * Returns: (transfer none): a floating reference to a new bytestring #GVariant instance
1756 g_variant_new_bytestring (const gchar *string)
1758 g_return_val_if_fail (string != NULL, NULL);
1760 return g_variant_new_from_trusted (G_VARIANT_TYPE_BYTESTRING,
1761 string, strlen (string) + 1);
1765 * g_variant_get_bytestring:
1766 * @value: an array-of-bytes #GVariant instance
1768 * Returns the string value of a #GVariant instance with an
1769 * array-of-bytes type. The string has no particular encoding.
1771 * If the array does not end with a nul terminator character, the empty
1772 * string is returned. For this reason, you can always trust that a
1773 * non-%NULL nul-terminated string will be returned by this function.
1775 * If the array contains a nul terminator character somewhere other than
1776 * the last byte then the returned string is the string, up to the first
1777 * such nul character.
1779 * It is an error to call this function with a @value that is not an
1782 * The return value remains valid as long as @value exists.
1784 * Returns: (transfer none) (array zero-terminated=1) (element-type guint8):
1785 * the constant string
1790 g_variant_get_bytestring (GVariant *value)
1792 const gchar *string;
1795 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING, NULL);
1797 /* Won't be NULL since this is an array type */
1798 string = g_variant_get_data (value);
1799 size = g_variant_get_size (value);
1801 if (size && string[size - 1] == '\0')
1808 * g_variant_dup_bytestring:
1809 * @value: an array-of-bytes #GVariant instance
1810 * @length: (out) (allow-none) (default NULL): a pointer to a #gsize, to store
1811 * the length (not including the nul terminator)
1813 * Similar to g_variant_get_bytestring() except that instead of
1814 * returning a constant string, the string is duplicated.
1816 * The return value must be freed using g_free().
1818 * Returns: (transfer full) (array zero-terminated=1 length=length) (element-type guint8):
1819 * a newly allocated string
1824 g_variant_dup_bytestring (GVariant *value,
1827 const gchar *original = g_variant_get_bytestring (value);
1830 /* don't crash in case get_bytestring() had an assert failure */
1831 if (original == NULL)
1834 size = strlen (original);
1839 return g_memdup (original, size + 1);
1843 * g_variant_new_bytestring_array:
1844 * @strv: (array length=length): an array of strings
1845 * @length: the length of @strv, or -1
1847 * Constructs an array of bytestring #GVariant from the given array of
1850 * If @length is -1 then @strv is %NULL-terminated.
1852 * Returns: (transfer none): a new floating #GVariant instance
1857 g_variant_new_bytestring_array (const gchar * const *strv,
1863 g_return_val_if_fail (length == 0 || strv != NULL, NULL);
1866 length = g_strv_length ((gchar **) strv);
1868 strings = g_new (GVariant *, length);
1869 for (i = 0; i < length; i++)
1870 strings[i] = g_variant_ref_sink (g_variant_new_bytestring (strv[i]));
1872 return g_variant_new_from_children (G_VARIANT_TYPE_BYTESTRING_ARRAY,
1873 strings, length, TRUE);
1877 * g_variant_get_bytestring_array:
1878 * @value: an array of array of bytes #GVariant ('aay')
1879 * @length: (out) (allow-none): the length of the result, or %NULL
1881 * Gets the contents of an array of array of bytes #GVariant. This call
1882 * makes a shallow copy; the return result should be released with
1883 * g_free(), but the individual strings must not be modified.
1885 * If @length is non-%NULL then the number of elements in the result is
1886 * stored there. In any case, the resulting array will be
1889 * For an empty array, @length will be set to 0 and a pointer to a
1890 * %NULL pointer will be returned.
1892 * Returns: (array length=length) (transfer container): an array of constant strings
1897 g_variant_get_bytestring_array (GVariant *value,
1904 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL);
1906 g_variant_get_data (value);
1907 n = g_variant_n_children (value);
1908 strv = g_new (const gchar *, n + 1);
1910 for (i = 0; i < n; i++)
1914 string = g_variant_get_child_value (value, i);
1915 strv[i] = g_variant_get_bytestring (string);
1916 g_variant_unref (string);
1927 * g_variant_dup_bytestring_array:
1928 * @value: an array of array of bytes #GVariant ('aay')
1929 * @length: (out) (allow-none): the length of the result, or %NULL
1931 * Gets the contents of an array of array of bytes #GVariant. This call
1932 * makes a deep copy; the return result should be released with
1935 * If @length is non-%NULL then the number of elements in the result is
1936 * stored there. In any case, the resulting array will be
1939 * For an empty array, @length will be set to 0 and a pointer to a
1940 * %NULL pointer will be returned.
1942 * Returns: (array length=length) (transfer full): an array of strings
1947 g_variant_dup_bytestring_array (GVariant *value,
1954 TYPE_CHECK (value, G_VARIANT_TYPE_BYTESTRING_ARRAY, NULL);
1956 g_variant_get_data (value);
1957 n = g_variant_n_children (value);
1958 strv = g_new (gchar *, n + 1);
1960 for (i = 0; i < n; i++)
1964 string = g_variant_get_child_value (value, i);
1965 strv[i] = g_variant_dup_bytestring (string, NULL);
1966 g_variant_unref (string);
1976 /* Type checking and querying {{{1 */
1978 * g_variant_get_type:
1979 * @value: a #GVariant
1981 * Determines the type of @value.
1983 * The return value is valid for the lifetime of @value and must not
1986 * Returns: a #GVariantType
1990 const GVariantType *
1991 g_variant_get_type (GVariant *value)
1993 GVariantTypeInfo *type_info;
1995 g_return_val_if_fail (value != NULL, NULL);
1997 type_info = g_variant_get_type_info (value);
1999 return (GVariantType *) g_variant_type_info_get_type_string (type_info);
2003 * g_variant_get_type_string:
2004 * @value: a #GVariant
2006 * Returns the type string of @value. Unlike the result of calling
2007 * g_variant_type_peek_string(), this string is nul-terminated. This
2008 * string belongs to #GVariant and must not be freed.
2010 * Returns: the type string for the type of @value
2015 g_variant_get_type_string (GVariant *value)
2017 GVariantTypeInfo *type_info;
2019 g_return_val_if_fail (value != NULL, NULL);
2021 type_info = g_variant_get_type_info (value);
2023 return g_variant_type_info_get_type_string (type_info);
2027 * g_variant_is_of_type:
2028 * @value: a #GVariant instance
2029 * @type: a #GVariantType
2031 * Checks if a value has a type matching the provided type.
2033 * Returns: %TRUE if the type of @value matches @type
2038 g_variant_is_of_type (GVariant *value,
2039 const GVariantType *type)
2041 return g_variant_type_is_subtype_of (g_variant_get_type (value), type);
2045 * g_variant_is_container:
2046 * @value: a #GVariant instance
2048 * Checks if @value is a container.
2050 * Returns: %TRUE if @value is a container
2055 g_variant_is_container (GVariant *value)
2057 return g_variant_type_is_container (g_variant_get_type (value));
2062 * g_variant_classify:
2063 * @value: a #GVariant
2065 * Classifies @value according to its top-level type.
2067 * Returns: the #GVariantClass of @value
2073 * @G_VARIANT_CLASS_BOOLEAN: The #GVariant is a boolean.
2074 * @G_VARIANT_CLASS_BYTE: The #GVariant is a byte.
2075 * @G_VARIANT_CLASS_INT16: The #GVariant is a signed 16 bit integer.
2076 * @G_VARIANT_CLASS_UINT16: The #GVariant is an unsigned 16 bit integer.
2077 * @G_VARIANT_CLASS_INT32: The #GVariant is a signed 32 bit integer.
2078 * @G_VARIANT_CLASS_UINT32: The #GVariant is an unsigned 32 bit integer.
2079 * @G_VARIANT_CLASS_INT64: The #GVariant is a signed 64 bit integer.
2080 * @G_VARIANT_CLASS_UINT64: The #GVariant is an unsigned 64 bit integer.
2081 * @G_VARIANT_CLASS_HANDLE: The #GVariant is a file handle index.
2082 * @G_VARIANT_CLASS_DOUBLE: The #GVariant is a double precision floating
2084 * @G_VARIANT_CLASS_STRING: The #GVariant is a normal string.
2085 * @G_VARIANT_CLASS_OBJECT_PATH: The #GVariant is a D-Bus object path
2087 * @G_VARIANT_CLASS_SIGNATURE: The #GVariant is a D-Bus signature string.
2088 * @G_VARIANT_CLASS_VARIANT: The #GVariant is a variant.
2089 * @G_VARIANT_CLASS_MAYBE: The #GVariant is a maybe-typed value.
2090 * @G_VARIANT_CLASS_ARRAY: The #GVariant is an array.
2091 * @G_VARIANT_CLASS_TUPLE: The #GVariant is a tuple.
2092 * @G_VARIANT_CLASS_DICT_ENTRY: The #GVariant is a dictionary entry.
2094 * The range of possible top-level types of #GVariant instances.
2099 g_variant_classify (GVariant *value)
2101 g_return_val_if_fail (value != NULL, 0);
2103 return *g_variant_get_type_string (value);
2106 /* Pretty printer {{{1 */
2107 /* This function is not introspectable because if @string is NULL,
2108 @returns is (transfer full), otherwise it is (transfer none), which
2109 is not supported by GObjectIntrospection */
2111 * g_variant_print_string: (skip)
2112 * @value: a #GVariant
2113 * @string: (allow-none) (default NULL): a #GString, or %NULL
2114 * @type_annotate: %TRUE if type information should be included in
2117 * Behaves as g_variant_print(), but operates on a #GString.
2119 * If @string is non-%NULL then it is appended to and returned. Else,
2120 * a new empty #GString is allocated and it is returned.
2122 * Returns: a #GString containing the string
2127 g_variant_print_string (GVariant *value,
2129 gboolean type_annotate)
2131 if G_UNLIKELY (string == NULL)
2132 string = g_string_new (NULL);
2134 switch (g_variant_classify (value))
2136 case G_VARIANT_CLASS_MAYBE:
2138 g_string_append_printf (string, "@%s ",
2139 g_variant_get_type_string (value));
2141 if (g_variant_n_children (value))
2143 gchar *printed_child;
2148 * Consider the case of the type "mmi". In this case we could
2149 * write "just just 4", but "4" alone is totally unambiguous,
2150 * so we try to drop "just" where possible.
2152 * We have to be careful not to always drop "just", though,
2153 * since "nothing" needs to be distinguishable from "just
2154 * nothing". The case where we need to ensure we keep the
2155 * "just" is actually exactly the case where we have a nested
2158 * Instead of searching for that nested Nothing, we just print
2159 * the contained value into a separate string and see if we
2160 * end up with "nothing" at the end of it. If so, we need to
2161 * add "just" at our level.
2163 element = g_variant_get_child_value (value, 0);
2164 printed_child = g_variant_print (element, FALSE);
2165 g_variant_unref (element);
2167 if (g_str_has_suffix (printed_child, "nothing"))
2168 g_string_append (string, "just ");
2169 g_string_append (string, printed_child);
2170 g_free (printed_child);
2173 g_string_append (string, "nothing");
2177 case G_VARIANT_CLASS_ARRAY:
2178 /* it's an array so the first character of the type string is 'a'
2180 * if the first two characters are 'ay' then it's a bytestring.
2181 * under certain conditions we print those as strings.
2183 if (g_variant_get_type_string (value)[1] == 'y')
2189 /* first determine if it is a byte string.
2190 * that's when there's a single nul character: at the end.
2192 str = g_variant_get_data (value);
2193 size = g_variant_get_size (value);
2195 for (i = 0; i < size; i++)
2199 /* first nul byte is the last byte -> it's a byte string. */
2202 gchar *escaped = g_strescape (str, NULL);
2204 /* use double quotes only if a ' is in the string */
2205 if (strchr (str, '\''))
2206 g_string_append_printf (string, "b\"%s\"", escaped);
2208 g_string_append_printf (string, "b'%s'", escaped);
2215 /* fall through and handle normally... */;
2219 * if the first two characters are 'a{' then it's an array of
2220 * dictionary entries (ie: a dictionary) so we print that
2223 if (g_variant_get_type_string (value)[1] == '{')
2226 const gchar *comma = "";
2229 if ((n = g_variant_n_children (value)) == 0)
2232 g_string_append_printf (string, "@%s ",
2233 g_variant_get_type_string (value));
2234 g_string_append (string, "{}");
2238 g_string_append_c (string, '{');
2239 for (i = 0; i < n; i++)
2241 GVariant *entry, *key, *val;
2243 g_string_append (string, comma);
2246 entry = g_variant_get_child_value (value, i);
2247 key = g_variant_get_child_value (entry, 0);
2248 val = g_variant_get_child_value (entry, 1);
2249 g_variant_unref (entry);
2251 g_variant_print_string (key, string, type_annotate);
2252 g_variant_unref (key);
2253 g_string_append (string, ": ");
2254 g_variant_print_string (val, string, type_annotate);
2255 g_variant_unref (val);
2256 type_annotate = FALSE;
2258 g_string_append_c (string, '}');
2261 /* normal (non-dictionary) array */
2263 const gchar *comma = "";
2266 if ((n = g_variant_n_children (value)) == 0)
2269 g_string_append_printf (string, "@%s ",
2270 g_variant_get_type_string (value));
2271 g_string_append (string, "[]");
2275 g_string_append_c (string, '[');
2276 for (i = 0; i < n; i++)
2280 g_string_append (string, comma);
2283 element = g_variant_get_child_value (value, i);
2285 g_variant_print_string (element, string, type_annotate);
2286 g_variant_unref (element);
2287 type_annotate = FALSE;
2289 g_string_append_c (string, ']');
2294 case G_VARIANT_CLASS_TUPLE:
2298 n = g_variant_n_children (value);
2300 g_string_append_c (string, '(');
2301 for (i = 0; i < n; i++)
2305 element = g_variant_get_child_value (value, i);
2306 g_variant_print_string (element, string, type_annotate);
2307 g_string_append (string, ", ");
2308 g_variant_unref (element);
2311 /* for >1 item: remove final ", "
2312 * for 1 item: remove final " ", but leave the ","
2313 * for 0 items: there is only "(", so remove nothing
2315 g_string_truncate (string, string->len - (n > 0) - (n > 1));
2316 g_string_append_c (string, ')');
2320 case G_VARIANT_CLASS_DICT_ENTRY:
2324 g_string_append_c (string, '{');
2326 element = g_variant_get_child_value (value, 0);
2327 g_variant_print_string (element, string, type_annotate);
2328 g_variant_unref (element);
2330 g_string_append (string, ", ");
2332 element = g_variant_get_child_value (value, 1);
2333 g_variant_print_string (element, string, type_annotate);
2334 g_variant_unref (element);
2336 g_string_append_c (string, '}');
2340 case G_VARIANT_CLASS_VARIANT:
2342 GVariant *child = g_variant_get_variant (value);
2344 /* Always annotate types in nested variants, because they are
2345 * (by nature) of variable type.
2347 g_string_append_c (string, '<');
2348 g_variant_print_string (child, string, TRUE);
2349 g_string_append_c (string, '>');
2351 g_variant_unref (child);
2355 case G_VARIANT_CLASS_BOOLEAN:
2356 if (g_variant_get_boolean (value))
2357 g_string_append (string, "true");
2359 g_string_append (string, "false");
2362 case G_VARIANT_CLASS_STRING:
2364 const gchar *str = g_variant_get_string (value, NULL);
2365 gunichar quote = strchr (str, '\'') ? '"' : '\'';
2367 g_string_append_c (string, quote);
2371 gunichar c = g_utf8_get_char (str);
2373 if (c == quote || c == '\\')
2374 g_string_append_c (string, '\\');
2376 if (g_unichar_isprint (c))
2377 g_string_append_unichar (string, c);
2381 g_string_append_c (string, '\\');
2386 g_string_append_c (string, 'a');
2390 g_string_append_c (string, 'b');
2394 g_string_append_c (string, 'f');
2398 g_string_append_c (string, 'n');
2402 g_string_append_c (string, 'r');
2406 g_string_append_c (string, 't');
2410 g_string_append_c (string, 'v');
2414 g_string_append_printf (string, "u%04x", c);
2418 g_string_append_printf (string, "U%08x", c);
2421 str = g_utf8_next_char (str);
2424 g_string_append_c (string, quote);
2428 case G_VARIANT_CLASS_BYTE:
2430 g_string_append (string, "byte ");
2431 g_string_append_printf (string, "0x%02x",
2432 g_variant_get_byte (value));
2435 case G_VARIANT_CLASS_INT16:
2437 g_string_append (string, "int16 ");
2438 g_string_append_printf (string, "%"G_GINT16_FORMAT,
2439 g_variant_get_int16 (value));
2442 case G_VARIANT_CLASS_UINT16:
2444 g_string_append (string, "uint16 ");
2445 g_string_append_printf (string, "%"G_GUINT16_FORMAT,
2446 g_variant_get_uint16 (value));
2449 case G_VARIANT_CLASS_INT32:
2450 /* Never annotate this type because it is the default for numbers
2451 * (and this is a *pretty* printer)
2453 g_string_append_printf (string, "%"G_GINT32_FORMAT,
2454 g_variant_get_int32 (value));
2457 case G_VARIANT_CLASS_HANDLE:
2459 g_string_append (string, "handle ");
2460 g_string_append_printf (string, "%"G_GINT32_FORMAT,
2461 g_variant_get_handle (value));
2464 case G_VARIANT_CLASS_UINT32:
2466 g_string_append (string, "uint32 ");
2467 g_string_append_printf (string, "%"G_GUINT32_FORMAT,
2468 g_variant_get_uint32 (value));
2471 case G_VARIANT_CLASS_INT64:
2473 g_string_append (string, "int64 ");
2474 g_string_append_printf (string, "%"G_GINT64_FORMAT,
2475 g_variant_get_int64 (value));
2478 case G_VARIANT_CLASS_UINT64:
2480 g_string_append (string, "uint64 ");
2481 g_string_append_printf (string, "%"G_GUINT64_FORMAT,
2482 g_variant_get_uint64 (value));
2485 case G_VARIANT_CLASS_DOUBLE:
2490 g_ascii_dtostr (buffer, sizeof buffer, g_variant_get_double (value));
2492 for (i = 0; buffer[i]; i++)
2493 if (buffer[i] == '.' || buffer[i] == 'e' ||
2494 buffer[i] == 'n' || buffer[i] == 'N')
2497 /* if there is no '.' or 'e' in the float then add one */
2498 if (buffer[i] == '\0')
2505 g_string_append (string, buffer);
2509 case G_VARIANT_CLASS_OBJECT_PATH:
2511 g_string_append (string, "objectpath ");
2512 g_string_append_printf (string, "\'%s\'",
2513 g_variant_get_string (value, NULL));
2516 case G_VARIANT_CLASS_SIGNATURE:
2518 g_string_append (string, "signature ");
2519 g_string_append_printf (string, "\'%s\'",
2520 g_variant_get_string (value, NULL));
2524 g_assert_not_reached ();
2532 * @value: a #GVariant
2533 * @type_annotate: %TRUE if type information should be included in
2536 * Pretty-prints @value in the format understood by g_variant_parse().
2538 * The format is described <link linkend='gvariant-text'>here</link>.
2540 * If @type_annotate is %TRUE, then type information is included in
2543 * Returns: (transfer full): a newly-allocated string holding the result.
2548 g_variant_print (GVariant *value,
2549 gboolean type_annotate)
2551 return g_string_free (g_variant_print_string (value, NULL, type_annotate),
2555 /* Hash, Equal, Compare {{{1 */
2558 * @value: (type GVariant): a basic #GVariant value as a #gconstpointer
2560 * Generates a hash value for a #GVariant instance.
2562 * The output of this function is guaranteed to be the same for a given
2563 * value only per-process. It may change between different processor
2564 * architectures or even different versions of GLib. Do not use this
2565 * function as a basis for building protocols or file formats.
2567 * The type of @value is #gconstpointer only to allow use of this
2568 * function with #GHashTable. @value must be a #GVariant.
2570 * Returns: a hash value corresponding to @value
2575 g_variant_hash (gconstpointer value_)
2577 GVariant *value = (GVariant *) value_;
2579 switch (g_variant_classify (value))
2581 case G_VARIANT_CLASS_STRING:
2582 case G_VARIANT_CLASS_OBJECT_PATH:
2583 case G_VARIANT_CLASS_SIGNATURE:
2584 return g_str_hash (g_variant_get_string (value, NULL));
2586 case G_VARIANT_CLASS_BOOLEAN:
2587 /* this is a very odd thing to hash... */
2588 return g_variant_get_boolean (value);
2590 case G_VARIANT_CLASS_BYTE:
2591 return g_variant_get_byte (value);
2593 case G_VARIANT_CLASS_INT16:
2594 case G_VARIANT_CLASS_UINT16:
2598 ptr = g_variant_get_data (value);
2606 case G_VARIANT_CLASS_INT32:
2607 case G_VARIANT_CLASS_UINT32:
2608 case G_VARIANT_CLASS_HANDLE:
2612 ptr = g_variant_get_data (value);
2620 case G_VARIANT_CLASS_INT64:
2621 case G_VARIANT_CLASS_UINT64:
2622 case G_VARIANT_CLASS_DOUBLE:
2623 /* need a separate case for these guys because otherwise
2624 * performance could be quite bad on big endian systems
2629 ptr = g_variant_get_data (value);
2632 return ptr[0] + ptr[1];
2638 g_return_val_if_fail (!g_variant_is_container (value), 0);
2639 g_assert_not_reached ();
2645 * @one: (type GVariant): a #GVariant instance
2646 * @two: (type GVariant): a #GVariant instance
2648 * Checks if @one and @two have the same type and value.
2650 * The types of @one and @two are #gconstpointer only to allow use of
2651 * this function with #GHashTable. They must each be a #GVariant.
2653 * Returns: %TRUE if @one and @two are equal
2658 g_variant_equal (gconstpointer one,
2663 g_return_val_if_fail (one != NULL && two != NULL, FALSE);
2665 if (g_variant_get_type_info ((GVariant *) one) !=
2666 g_variant_get_type_info ((GVariant *) two))
2669 /* if both values are trusted to be in their canonical serialised form
2670 * then a simple memcmp() of their serialised data will answer the
2673 * if not, then this might generate a false negative (since it is
2674 * possible for two different byte sequences to represent the same
2675 * value). for now we solve this by pretty-printing both values and
2676 * comparing the result.
2678 if (g_variant_is_trusted ((GVariant *) one) &&
2679 g_variant_is_trusted ((GVariant *) two))
2681 gconstpointer data_one, data_two;
2682 gsize size_one, size_two;
2684 size_one = g_variant_get_size ((GVariant *) one);
2685 size_two = g_variant_get_size ((GVariant *) two);
2687 if (size_one != size_two)
2690 data_one = g_variant_get_data ((GVariant *) one);
2691 data_two = g_variant_get_data ((GVariant *) two);
2693 equal = memcmp (data_one, data_two, size_one) == 0;
2697 gchar *strone, *strtwo;
2699 strone = g_variant_print ((GVariant *) one, FALSE);
2700 strtwo = g_variant_print ((GVariant *) two, FALSE);
2701 equal = strcmp (strone, strtwo) == 0;
2710 * g_variant_compare:
2711 * @one: (type GVariant): a basic-typed #GVariant instance
2712 * @two: (type GVariant): a #GVariant instance of the same type
2714 * Compares @one and @two.
2716 * The types of @one and @two are #gconstpointer only to allow use of
2717 * this function with #GTree, #GPtrArray, etc. They must each be a
2720 * Comparison is only defined for basic types (ie: booleans, numbers,
2721 * strings). For booleans, %FALSE is less than %TRUE. Numbers are
2722 * ordered in the usual way. Strings are in ASCII lexographical order.
2724 * It is a programmer error to attempt to compare container values or
2725 * two values that have types that are not exactly equal. For example,
2726 * you cannot compare a 32-bit signed integer with a 32-bit unsigned
2727 * integer. Also note that this function is not particularly
2728 * well-behaved when it comes to comparison of doubles; in particular,
2729 * the handling of incomparable values (ie: NaN) is undefined.
2731 * If you only require an equality comparison, g_variant_equal() is more
2734 * Returns: negative value if a < b;
2736 * positive value if a > b.
2741 g_variant_compare (gconstpointer one,
2744 GVariant *a = (GVariant *) one;
2745 GVariant *b = (GVariant *) two;
2747 g_return_val_if_fail (g_variant_classify (a) == g_variant_classify (b), 0);
2749 switch (g_variant_classify (a))
2751 case G_VARIANT_CLASS_BYTE:
2752 return ((gint) g_variant_get_byte (a)) -
2753 ((gint) g_variant_get_byte (b));
2755 case G_VARIANT_CLASS_INT16:
2756 return ((gint) g_variant_get_int16 (a)) -
2757 ((gint) g_variant_get_int16 (b));
2759 case G_VARIANT_CLASS_UINT16:
2760 return ((gint) g_variant_get_uint16 (a)) -
2761 ((gint) g_variant_get_uint16 (b));
2763 case G_VARIANT_CLASS_INT32:
2765 gint32 a_val = g_variant_get_int32 (a);
2766 gint32 b_val = g_variant_get_int32 (b);
2768 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2771 case G_VARIANT_CLASS_UINT32:
2773 guint32 a_val = g_variant_get_uint32 (a);
2774 guint32 b_val = g_variant_get_uint32 (b);
2776 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2779 case G_VARIANT_CLASS_INT64:
2781 gint64 a_val = g_variant_get_int64 (a);
2782 gint64 b_val = g_variant_get_int64 (b);
2784 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2787 case G_VARIANT_CLASS_UINT64:
2789 guint64 a_val = g_variant_get_uint64 (a);
2790 guint64 b_val = g_variant_get_uint64 (b);
2792 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2795 case G_VARIANT_CLASS_DOUBLE:
2797 gdouble a_val = g_variant_get_double (a);
2798 gdouble b_val = g_variant_get_double (b);
2800 return (a_val == b_val) ? 0 : (a_val > b_val) ? 1 : -1;
2803 case G_VARIANT_CLASS_STRING:
2804 case G_VARIANT_CLASS_OBJECT_PATH:
2805 case G_VARIANT_CLASS_SIGNATURE:
2806 return strcmp (g_variant_get_string (a, NULL),
2807 g_variant_get_string (b, NULL));
2810 g_return_val_if_fail (!g_variant_is_container (a), 0);
2811 g_assert_not_reached ();
2815 /* GVariantIter {{{1 */
2817 * GVariantIter: (skip)
2819 * #GVariantIter is an opaque data structure and can only be accessed
2820 * using the following functions.
2827 const gchar *loop_format;
2833 G_STATIC_ASSERT (sizeof (struct stack_iter) <= sizeof (GVariantIter));
2837 struct stack_iter iter;
2839 GVariant *value_ref;
2843 #define GVSI(i) ((struct stack_iter *) (i))
2844 #define GVHI(i) ((struct heap_iter *) (i))
2845 #define GVSI_MAGIC ((gsize) 3579507750u)
2846 #define GVHI_MAGIC ((gsize) 1450270775u)
2847 #define is_valid_iter(i) (i != NULL && \
2848 GVSI(i)->magic == GVSI_MAGIC)
2849 #define is_valid_heap_iter(i) (GVHI(i)->magic == GVHI_MAGIC && \
2853 * g_variant_iter_new:
2854 * @value: a container #GVariant
2856 * Creates a heap-allocated #GVariantIter for iterating over the items
2859 * Use g_variant_iter_free() to free the return value when you no longer
2862 * A reference is taken to @value and will be released only when
2863 * g_variant_iter_free() is called.
2865 * Returns: (transfer full): a new heap-allocated #GVariantIter
2870 g_variant_iter_new (GVariant *value)
2874 iter = (GVariantIter *) g_slice_new (struct heap_iter);
2875 GVHI(iter)->value_ref = g_variant_ref (value);
2876 GVHI(iter)->magic = GVHI_MAGIC;
2878 g_variant_iter_init (iter, value);
2884 * g_variant_iter_init: (skip)
2885 * @iter: a pointer to a #GVariantIter
2886 * @value: a container #GVariant
2888 * Initialises (without allocating) a #GVariantIter. @iter may be
2889 * completely uninitialised prior to this call; its old value is
2892 * The iterator remains valid for as long as @value exists, and need not
2893 * be freed in any way.
2895 * Returns: the number of items in @value
2900 g_variant_iter_init (GVariantIter *iter,
2903 GVSI(iter)->magic = GVSI_MAGIC;
2904 GVSI(iter)->value = value;
2905 GVSI(iter)->n = g_variant_n_children (value);
2907 GVSI(iter)->loop_format = NULL;
2909 return GVSI(iter)->n;
2913 * g_variant_iter_copy:
2914 * @iter: a #GVariantIter
2916 * Creates a new heap-allocated #GVariantIter to iterate over the
2917 * container that was being iterated over by @iter. Iteration begins on
2918 * the new iterator from the current position of the old iterator but
2919 * the two copies are independent past that point.
2921 * Use g_variant_iter_free() to free the return value when you no longer
2924 * A reference is taken to the container that @iter is iterating over
2925 * and will be releated only when g_variant_iter_free() is called.
2927 * Returns: (transfer full): a new heap-allocated #GVariantIter
2932 g_variant_iter_copy (GVariantIter *iter)
2936 g_return_val_if_fail (is_valid_iter (iter), 0);
2938 copy = g_variant_iter_new (GVSI(iter)->value);
2939 GVSI(copy)->i = GVSI(iter)->i;
2945 * g_variant_iter_n_children:
2946 * @iter: a #GVariantIter
2948 * Queries the number of child items in the container that we are
2949 * iterating over. This is the total number of items -- not the number
2950 * of items remaining.
2952 * This function might be useful for preallocation of arrays.
2954 * Returns: the number of children in the container
2959 g_variant_iter_n_children (GVariantIter *iter)
2961 g_return_val_if_fail (is_valid_iter (iter), 0);
2963 return GVSI(iter)->n;
2967 * g_variant_iter_free:
2968 * @iter: (transfer full): a heap-allocated #GVariantIter
2970 * Frees a heap-allocated #GVariantIter. Only call this function on
2971 * iterators that were returned by g_variant_iter_new() or
2972 * g_variant_iter_copy().
2977 g_variant_iter_free (GVariantIter *iter)
2979 g_return_if_fail (is_valid_heap_iter (iter));
2981 g_variant_unref (GVHI(iter)->value_ref);
2982 GVHI(iter)->magic = 0;
2984 g_slice_free (struct heap_iter, GVHI(iter));
2988 * g_variant_iter_next_value:
2989 * @iter: a #GVariantIter
2991 * Gets the next item in the container. If no more items remain then
2992 * %NULL is returned.
2994 * Use g_variant_unref() to drop your reference on the return value when
2995 * you no longer need it.
2998 * <title>Iterating with g_variant_iter_next_value()</title>
3000 * /<!-- -->* recursively iterate a container *<!-- -->/
3002 * iterate_container_recursive (GVariant *container)
3004 * GVariantIter iter;
3007 * g_variant_iter_init (&iter, container);
3008 * while ((child = g_variant_iter_next_value (&iter)))
3010 * g_print ("type '%s'\n", g_variant_get_type_string (child));
3012 * if (g_variant_is_container (child))
3013 * iterate_container_recursive (child);
3015 * g_variant_unref (child);
3021 * Returns: (allow-none) (transfer full): a #GVariant, or %NULL
3026 g_variant_iter_next_value (GVariantIter *iter)
3028 g_return_val_if_fail (is_valid_iter (iter), FALSE);
3030 if G_UNLIKELY (GVSI(iter)->i >= GVSI(iter)->n)
3032 g_critical ("g_variant_iter_next_value: must not be called again "
3033 "after NULL has already been returned.");
3039 if (GVSI(iter)->i < GVSI(iter)->n)
3040 return g_variant_get_child_value (GVSI(iter)->value, GVSI(iter)->i);
3045 /* GVariantBuilder {{{1 */
3049 * A utility type for constructing container-type #GVariant instances.
3051 * This is an opaque structure and may only be accessed using the
3052 * following functions.
3054 * #GVariantBuilder is not threadsafe in any way. Do not attempt to
3055 * access it from more than one thread.
3058 struct stack_builder
3060 GVariantBuilder *parent;
3063 /* type constraint explicitly specified by 'type'.
3064 * for tuple types, this moves along as we add more items.
3066 const GVariantType *expected_type;
3068 /* type constraint implied by previous array item.
3070 const GVariantType *prev_item_type;
3072 /* constraints on the number of children. max = -1 for unlimited. */
3076 /* dynamically-growing pointer array */
3077 GVariant **children;
3078 gsize allocated_children;
3081 /* set to '1' if all items in the container will have the same type
3082 * (ie: maybe, array, variant) '0' if not (ie: tuple, dict entry)
3084 guint uniform_item_types : 1;
3086 /* set to '1' initially and changed to '0' if an untrusted value is
3094 G_STATIC_ASSERT (sizeof (struct stack_builder) <= sizeof (GVariantBuilder));
3098 GVariantBuilder builder;
3104 #define GVSB(b) ((struct stack_builder *) (b))
3105 #define GVHB(b) ((struct heap_builder *) (b))
3106 #define GVSB_MAGIC ((gsize) 1033660112u)
3107 #define GVHB_MAGIC ((gsize) 3087242682u)
3108 #define is_valid_builder(b) (b != NULL && \
3109 GVSB(b)->magic == GVSB_MAGIC)
3110 #define is_valid_heap_builder(b) (GVHB(b)->magic == GVHB_MAGIC)
3113 * g_variant_builder_new:
3114 * @type: a container type
3116 * Allocates and initialises a new #GVariantBuilder.
3118 * You should call g_variant_builder_unref() on the return value when it
3119 * is no longer needed. The memory will not be automatically freed by
3122 * In most cases it is easier to place a #GVariantBuilder directly on
3123 * the stack of the calling function and initialise it with
3124 * g_variant_builder_init().
3126 * Returns: (transfer full): a #GVariantBuilder
3131 g_variant_builder_new (const GVariantType *type)
3133 GVariantBuilder *builder;
3135 builder = (GVariantBuilder *) g_slice_new (struct heap_builder);
3136 g_variant_builder_init (builder, type);
3137 GVHB(builder)->magic = GVHB_MAGIC;
3138 GVHB(builder)->ref_count = 1;
3144 * g_variant_builder_unref:
3145 * @builder: (transfer full): a #GVariantBuilder allocated by g_variant_builder_new()
3147 * Decreases the reference count on @builder.
3149 * In the event that there are no more references, releases all memory
3150 * associated with the #GVariantBuilder.
3152 * Don't call this on stack-allocated #GVariantBuilder instances or bad
3153 * things will happen.
3158 g_variant_builder_unref (GVariantBuilder *builder)
3160 g_return_if_fail (is_valid_heap_builder (builder));
3162 if (--GVHB(builder)->ref_count)
3165 g_variant_builder_clear (builder);
3166 GVHB(builder)->magic = 0;
3168 g_slice_free (struct heap_builder, GVHB(builder));
3172 * g_variant_builder_ref:
3173 * @builder: a #GVariantBuilder allocated by g_variant_builder_new()
3175 * Increases the reference count on @builder.
3177 * Don't call this on stack-allocated #GVariantBuilder instances or bad
3178 * things will happen.
3180 * Returns: (transfer full): a new reference to @builder
3185 g_variant_builder_ref (GVariantBuilder *builder)
3187 g_return_val_if_fail (is_valid_heap_builder (builder), NULL);
3189 GVHB(builder)->ref_count++;
3195 * g_variant_builder_clear: (skip)
3196 * @builder: a #GVariantBuilder
3198 * Releases all memory associated with a #GVariantBuilder without
3199 * freeing the #GVariantBuilder structure itself.
3201 * It typically only makes sense to do this on a stack-allocated
3202 * #GVariantBuilder if you want to abort building the value part-way
3203 * through. This function need not be called if you call
3204 * g_variant_builder_end() and it also doesn't need to be called on
3205 * builders allocated with g_variant_builder_new (see
3206 * g_variant_builder_unref() for that).
3208 * This function leaves the #GVariantBuilder structure set to all-zeros.
3209 * It is valid to call this function on either an initialised
3210 * #GVariantBuilder or one that is set to all-zeros but it is not valid
3211 * to call this function on uninitialised memory.
3216 g_variant_builder_clear (GVariantBuilder *builder)
3220 if (GVSB(builder)->magic == 0)
3221 /* all-zeros case */
3224 g_return_if_fail (is_valid_builder (builder));
3226 g_variant_type_free (GVSB(builder)->type);
3228 for (i = 0; i < GVSB(builder)->offset; i++)
3229 g_variant_unref (GVSB(builder)->children[i]);
3231 g_free (GVSB(builder)->children);
3233 if (GVSB(builder)->parent)
3235 g_variant_builder_clear (GVSB(builder)->parent);
3236 g_slice_free (GVariantBuilder, GVSB(builder)->parent);
3239 memset (builder, 0, sizeof (GVariantBuilder));
3243 * g_variant_builder_init: (skip)
3244 * @builder: a #GVariantBuilder
3245 * @type: a container type
3247 * Initialises a #GVariantBuilder structure.
3249 * @type must be non-%NULL. It specifies the type of container to
3250 * construct. It can be an indefinite type such as
3251 * %G_VARIANT_TYPE_ARRAY or a definite type such as "as" or "(ii)".
3252 * Maybe, array, tuple, dictionary entry and variant-typed values may be
3255 * After the builder is initialised, values are added using
3256 * g_variant_builder_add_value() or g_variant_builder_add().
3258 * After all the child values are added, g_variant_builder_end() frees
3259 * the memory associated with the builder and returns the #GVariant that
3262 * This function completely ignores the previous contents of @builder.
3263 * On one hand this means that it is valid to pass in completely
3264 * uninitialised memory. On the other hand, this means that if you are
3265 * initialising over top of an existing #GVariantBuilder you need to
3266 * first call g_variant_builder_clear() in order to avoid leaking
3269 * You must not call g_variant_builder_ref() or
3270 * g_variant_builder_unref() on a #GVariantBuilder that was initialised
3271 * with this function. If you ever pass a reference to a
3272 * #GVariantBuilder outside of the control of your own code then you
3273 * should assume that the person receiving that reference may try to use
3274 * reference counting; you should use g_variant_builder_new() instead of
3280 g_variant_builder_init (GVariantBuilder *builder,
3281 const GVariantType *type)
3283 g_return_if_fail (type != NULL);
3284 g_return_if_fail (g_variant_type_is_container (type));
3286 memset (builder, 0, sizeof (GVariantBuilder));
3288 GVSB(builder)->type = g_variant_type_copy (type);
3289 GVSB(builder)->magic = GVSB_MAGIC;
3290 GVSB(builder)->trusted = TRUE;
3292 switch (*(const gchar *) type)
3294 case G_VARIANT_CLASS_VARIANT:
3295 GVSB(builder)->uniform_item_types = TRUE;
3296 GVSB(builder)->allocated_children = 1;
3297 GVSB(builder)->expected_type = NULL;
3298 GVSB(builder)->min_items = 1;
3299 GVSB(builder)->max_items = 1;
3302 case G_VARIANT_CLASS_ARRAY:
3303 GVSB(builder)->uniform_item_types = TRUE;
3304 GVSB(builder)->allocated_children = 8;
3305 GVSB(builder)->expected_type =
3306 g_variant_type_element (GVSB(builder)->type);
3307 GVSB(builder)->min_items = 0;
3308 GVSB(builder)->max_items = -1;
3311 case G_VARIANT_CLASS_MAYBE:
3312 GVSB(builder)->uniform_item_types = TRUE;
3313 GVSB(builder)->allocated_children = 1;
3314 GVSB(builder)->expected_type =
3315 g_variant_type_element (GVSB(builder)->type);
3316 GVSB(builder)->min_items = 0;
3317 GVSB(builder)->max_items = 1;
3320 case G_VARIANT_CLASS_DICT_ENTRY:
3321 GVSB(builder)->uniform_item_types = FALSE;
3322 GVSB(builder)->allocated_children = 2;
3323 GVSB(builder)->expected_type =
3324 g_variant_type_key (GVSB(builder)->type);
3325 GVSB(builder)->min_items = 2;
3326 GVSB(builder)->max_items = 2;
3329 case 'r': /* G_VARIANT_TYPE_TUPLE was given */
3330 GVSB(builder)->uniform_item_types = FALSE;
3331 GVSB(builder)->allocated_children = 8;
3332 GVSB(builder)->expected_type = NULL;
3333 GVSB(builder)->min_items = 0;
3334 GVSB(builder)->max_items = -1;
3337 case G_VARIANT_CLASS_TUPLE: /* a definite tuple type was given */
3338 GVSB(builder)->allocated_children = g_variant_type_n_items (type);
3339 GVSB(builder)->expected_type =
3340 g_variant_type_first (GVSB(builder)->type);
3341 GVSB(builder)->min_items = GVSB(builder)->allocated_children;
3342 GVSB(builder)->max_items = GVSB(builder)->allocated_children;
3343 GVSB(builder)->uniform_item_types = FALSE;
3347 g_assert_not_reached ();
3350 GVSB(builder)->children = g_new (GVariant *,
3351 GVSB(builder)->allocated_children);
3355 g_variant_builder_make_room (struct stack_builder *builder)
3357 if (builder->offset == builder->allocated_children)
3359 builder->allocated_children *= 2;
3360 builder->children = g_renew (GVariant *, builder->children,
3361 builder->allocated_children);
3366 * g_variant_builder_add_value:
3367 * @builder: a #GVariantBuilder
3368 * @value: a #GVariant
3370 * Adds @value to @builder.
3372 * It is an error to call this function in any way that would create an
3373 * inconsistent value to be constructed. Some examples of this are
3374 * putting different types of items into an array, putting the wrong
3375 * types or number of items in a tuple, putting more than one value into
3378 * If @value is a floating reference (see g_variant_ref_sink()),
3379 * the @builder instance takes ownership of @value.
3384 g_variant_builder_add_value (GVariantBuilder *builder,
3387 g_return_if_fail (is_valid_builder (builder));
3388 g_return_if_fail (GVSB(builder)->offset < GVSB(builder)->max_items);
3389 g_return_if_fail (!GVSB(builder)->expected_type ||
3390 g_variant_is_of_type (value,
3391 GVSB(builder)->expected_type));
3392 g_return_if_fail (!GVSB(builder)->prev_item_type ||
3393 g_variant_is_of_type (value,
3394 GVSB(builder)->prev_item_type));
3396 GVSB(builder)->trusted &= g_variant_is_trusted (value);
3398 if (!GVSB(builder)->uniform_item_types)
3400 /* advance our expected type pointers */
3401 if (GVSB(builder)->expected_type)
3402 GVSB(builder)->expected_type =
3403 g_variant_type_next (GVSB(builder)->expected_type);
3405 if (GVSB(builder)->prev_item_type)
3406 GVSB(builder)->prev_item_type =
3407 g_variant_type_next (GVSB(builder)->prev_item_type);
3410 GVSB(builder)->prev_item_type = g_variant_get_type (value);
3412 g_variant_builder_make_room (GVSB(builder));
3414 GVSB(builder)->children[GVSB(builder)->offset++] =
3415 g_variant_ref_sink (value);
3419 * g_variant_builder_open:
3420 * @builder: a #GVariantBuilder
3421 * @type: a #GVariantType
3423 * Opens a subcontainer inside the given @builder. When done adding
3424 * items to the subcontainer, g_variant_builder_close() must be called.
3426 * It is an error to call this function in any way that would cause an
3427 * inconsistent value to be constructed (ie: adding too many values or
3428 * a value of an incorrect type).
3433 g_variant_builder_open (GVariantBuilder *builder,
3434 const GVariantType *type)
3436 GVariantBuilder *parent;
3438 g_return_if_fail (is_valid_builder (builder));
3439 g_return_if_fail (GVSB(builder)->offset < GVSB(builder)->max_items);
3440 g_return_if_fail (!GVSB(builder)->expected_type ||
3441 g_variant_type_is_subtype_of (type,
3442 GVSB(builder)->expected_type));
3443 g_return_if_fail (!GVSB(builder)->prev_item_type ||
3444 g_variant_type_is_subtype_of (GVSB(builder)->prev_item_type,
3447 parent = g_slice_dup (GVariantBuilder, builder);
3448 g_variant_builder_init (builder, type);
3449 GVSB(builder)->parent = parent;
3451 /* push the prev_item_type down into the subcontainer */
3452 if (GVSB(parent)->prev_item_type)
3454 if (!GVSB(builder)->uniform_item_types)
3455 /* tuples and dict entries */
3456 GVSB(builder)->prev_item_type =
3457 g_variant_type_first (GVSB(parent)->prev_item_type);
3459 else if (!g_variant_type_is_variant (GVSB(builder)->type))
3460 /* maybes and arrays */
3461 GVSB(builder)->prev_item_type =
3462 g_variant_type_element (GVSB(parent)->prev_item_type);
3467 * g_variant_builder_close:
3468 * @builder: a #GVariantBuilder
3470 * Closes the subcontainer inside the given @builder that was opened by
3471 * the most recent call to g_variant_builder_open().
3473 * It is an error to call this function in any way that would create an
3474 * inconsistent value to be constructed (ie: too few values added to the
3480 g_variant_builder_close (GVariantBuilder *builder)
3482 GVariantBuilder *parent;
3484 g_return_if_fail (is_valid_builder (builder));
3485 g_return_if_fail (GVSB(builder)->parent != NULL);
3487 parent = GVSB(builder)->parent;
3488 GVSB(builder)->parent = NULL;
3490 g_variant_builder_add_value (parent, g_variant_builder_end (builder));
3493 g_slice_free (GVariantBuilder, parent);
3497 * g_variant_make_maybe_type:
3498 * @element: a #GVariant
3500 * Return the type of a maybe containing @element.
3502 static GVariantType *
3503 g_variant_make_maybe_type (GVariant *element)
3505 return g_variant_type_new_maybe (g_variant_get_type (element));
3509 * g_variant_make_array_type:
3510 * @element: a #GVariant
3512 * Return the type of an array containing @element.
3514 static GVariantType *
3515 g_variant_make_array_type (GVariant *element)
3517 return g_variant_type_new_array (g_variant_get_type (element));
3521 * g_variant_builder_end:
3522 * @builder: a #GVariantBuilder
3524 * Ends the builder process and returns the constructed value.
3526 * It is not permissible to use @builder in any way after this call
3527 * except for reference counting operations (in the case of a
3528 * heap-allocated #GVariantBuilder) or by reinitialising it with
3529 * g_variant_builder_init() (in the case of stack-allocated).
3531 * It is an error to call this function in any way that would create an
3532 * inconsistent value to be constructed (ie: insufficient number of
3533 * items added to a container with a specific number of children
3534 * required). It is also an error to call this function if the builder
3535 * was created with an indefinite array or maybe type and no children
3536 * have been added; in this case it is impossible to infer the type of
3539 * Returns: (transfer none): a new, floating, #GVariant
3544 g_variant_builder_end (GVariantBuilder *builder)
3546 GVariantType *my_type;
3549 g_return_val_if_fail (is_valid_builder (builder), NULL);
3550 g_return_val_if_fail (GVSB(builder)->offset >= GVSB(builder)->min_items,
3552 g_return_val_if_fail (!GVSB(builder)->uniform_item_types ||
3553 GVSB(builder)->prev_item_type != NULL ||
3554 g_variant_type_is_definite (GVSB(builder)->type),
3557 if (g_variant_type_is_definite (GVSB(builder)->type))
3558 my_type = g_variant_type_copy (GVSB(builder)->type);
3560 else if (g_variant_type_is_maybe (GVSB(builder)->type))
3561 my_type = g_variant_make_maybe_type (GVSB(builder)->children[0]);
3563 else if (g_variant_type_is_array (GVSB(builder)->type))
3564 my_type = g_variant_make_array_type (GVSB(builder)->children[0]);
3566 else if (g_variant_type_is_tuple (GVSB(builder)->type))
3567 my_type = g_variant_make_tuple_type (GVSB(builder)->children,
3568 GVSB(builder)->offset);
3570 else if (g_variant_type_is_dict_entry (GVSB(builder)->type))
3571 my_type = g_variant_make_dict_entry_type (GVSB(builder)->children[0],
3572 GVSB(builder)->children[1]);
3574 g_assert_not_reached ();
3576 value = g_variant_new_from_children (my_type,
3577 g_renew (GVariant *,
3578 GVSB(builder)->children,
3579 GVSB(builder)->offset),
3580 GVSB(builder)->offset,
3581 GVSB(builder)->trusted);
3582 GVSB(builder)->children = NULL;
3583 GVSB(builder)->offset = 0;
3585 g_variant_builder_clear (builder);
3586 g_variant_type_free (my_type);
3591 /* Format strings {{{1 */
3593 * g_variant_format_string_scan:
3594 * @string: a string that may be prefixed with a format string
3595 * @limit: (allow-none) (default NULL): a pointer to the end of @string,
3597 * @endptr: (allow-none) (default NULL): location to store the end pointer,
3600 * Checks the string pointed to by @string for starting with a properly
3601 * formed #GVariant varargs format string. If no valid format string is
3602 * found then %FALSE is returned.
3604 * If @string does start with a valid format string then %TRUE is
3605 * returned. If @endptr is non-%NULL then it is updated to point to the
3606 * first character after the format string.
3608 * If @limit is non-%NULL then @limit (and any charater after it) will
3609 * not be accessed and the effect is otherwise equivalent to if the
3610 * character at @limit were nul.
3612 * See the section on <link linkend='gvariant-format-strings'>GVariant
3613 * Format Strings</link>.
3615 * Returns: %TRUE if there was a valid format string
3620 g_variant_format_string_scan (const gchar *string,
3622 const gchar **endptr)
3624 #define next_char() (string == limit ? '\0' : *string++)
3625 #define peek_char() (string == limit ? '\0' : *string)
3628 switch (next_char())
3630 case 'b': case 'y': case 'n': case 'q': case 'i': case 'u':
3631 case 'x': case 't': case 'h': case 'd': case 's': case 'o':
3632 case 'g': case 'v': case '*': case '?': case 'r':
3636 return g_variant_format_string_scan (string, limit, endptr);
3640 return g_variant_type_string_scan (string, limit, endptr);
3643 while (peek_char() != ')')
3644 if (!g_variant_format_string_scan (string, limit, &string))
3647 next_char(); /* consume ')' */
3657 if (c != 's' && c != 'o' && c != 'g')
3665 /* ISO/IEC 9899:1999 (C99) §7.21.5.2:
3666 * The terminating null character is considered to be
3667 * part of the string.
3669 if (c != '\0' && strchr ("bynqiuxthdsog?", c) == NULL)
3673 if (!g_variant_format_string_scan (string, limit, &string))
3676 if (next_char() != '}')
3682 if ((c = next_char()) == 'a')
3684 if ((c = next_char()) == '&')
3686 if ((c = next_char()) == 'a')
3688 if ((c = next_char()) == 'y')
3689 break; /* '^a&ay' */
3692 else if (c == 's' || c == 'o')
3693 break; /* '^a&s', '^a&o' */
3698 if ((c = next_char()) == 'y')
3702 else if (c == 's' || c == 'o')
3703 break; /* '^as', '^ao' */
3710 if ((c = next_char()) == 'a')
3712 if ((c = next_char()) == 'y')
3722 if (c != 's' && c != 'o' && c != 'g')
3741 * g_variant_format_string_scan_type:
3742 * @string: a string that may be prefixed with a format string
3743 * @limit: (allow-none) (default NULL): a pointer to the end of @string,
3745 * @endptr: (allow-none) (default NULL): location to store the end pointer,
3748 * If @string starts with a valid format string then this function will
3749 * return the type that the format string corresponds to. Otherwise
3750 * this function returns %NULL.
3752 * Use g_variant_type_free() to free the return value when you no longer
3755 * This function is otherwise exactly like
3756 * g_variant_format_string_scan().
3758 * Returns: (allow-none): a #GVariantType if there was a valid format string
3763 g_variant_format_string_scan_type (const gchar *string,
3765 const gchar **endptr)
3767 const gchar *my_end;
3774 if (!g_variant_format_string_scan (string, limit, endptr))
3777 dest = new = g_malloc (*endptr - string + 1);
3778 while (string != *endptr)
3780 if (*string != '@' && *string != '&' && *string != '^')
3786 return (GVariantType *) G_VARIANT_TYPE (new);
3790 valid_format_string (const gchar *format_string,
3794 const gchar *endptr;
3797 type = g_variant_format_string_scan_type (format_string, NULL, &endptr);
3799 if G_UNLIKELY (type == NULL || (single && *endptr != '\0'))
3802 g_critical ("`%s' is not a valid GVariant format string",
3805 g_critical ("`%s' does not have a valid GVariant format "
3806 "string as a prefix", format_string);
3809 g_variant_type_free (type);
3814 if G_UNLIKELY (value && !g_variant_is_of_type (value, type))
3819 fragment = g_strndup (format_string, endptr - format_string);
3820 typestr = g_variant_type_dup_string (type);
3822 g_critical ("the GVariant format string `%s' has a type of "
3823 "`%s' but the given value has a type of `%s'",
3824 fragment, typestr, g_variant_get_type_string (value));
3826 g_variant_type_free (type);
3831 g_variant_type_free (type);
3836 /* Variable Arguments {{{1 */
3837 /* We consider 2 main classes of format strings:
3839 * - recursive format strings
3840 * these are ones that result in recursion and the collection of
3841 * possibly more than one argument. Maybe types, tuples,
3842 * dictionary entries.
3844 * - leaf format string
3845 * these result in the collection of a single argument.
3847 * Leaf format strings are further subdivided into two categories:
3849 * - single non-null pointer ("nnp")
3850 * these either collect or return a single non-null pointer.
3853 * these collect or return something else (bool, number, etc).
3855 * Based on the above, the varargs handling code is split into 4 main parts:
3857 * - nnp handling code
3858 * - leaf handling code (which may invoke nnp code)
3859 * - generic handling code (may be recursive, may invoke leaf code)
3860 * - user-facing API (which invokes the generic code)
3862 * Each section implements some of the following functions:
3865 * collect the arguments for the format string as if
3866 * g_variant_new() had been called, but do nothing with them. used
3867 * for skipping over arguments when constructing a Nothing maybe
3871 * create a GVariant *
3874 * unpack a GVariant *
3876 * - free (nnp only):
3877 * free a previously allocated item
3881 g_variant_format_string_is_leaf (const gchar *str)
3883 return str[0] != 'm' && str[0] != '(' && str[0] != '{';
3887 g_variant_format_string_is_nnp (const gchar *str)
3889 return str[0] == 'a' || str[0] == 's' || str[0] == 'o' || str[0] == 'g' ||
3890 str[0] == '^' || str[0] == '@' || str[0] == '*' || str[0] == '?' ||
3891 str[0] == 'r' || str[0] == 'v' || str[0] == '&';
3894 /* Single non-null pointer ("nnp") {{{2 */
3896 g_variant_valist_free_nnp (const gchar *str,
3902 g_variant_iter_free (ptr);
3906 if (str[2] != '&') /* '^as', '^ao' */
3908 else /* '^a&s', '^a&o' */
3922 g_variant_unref (ptr);
3929 g_assert_not_reached ();
3934 g_variant_scan_convenience (const gchar **str,
3957 g_variant_valist_new_nnp (const gchar **str,
3968 const GVariantType *type;
3971 value = g_variant_builder_end (ptr);
3972 type = g_variant_get_type (value);
3974 if G_UNLIKELY (!g_variant_type_is_array (type))
3975 g_error ("g_variant_new: expected array GVariantBuilder but "
3976 "the built value has type `%s'",
3977 g_variant_get_type_string (value));
3979 type = g_variant_type_element (type);
3981 if G_UNLIKELY (!g_variant_type_is_subtype_of (type, (GVariantType *) *str))
3982 g_error ("g_variant_new: expected GVariantBuilder array element "
3983 "type `%s' but the built value has element type `%s'",
3984 g_variant_type_dup_string ((GVariantType *) *str),
3985 g_variant_get_type_string (value) + 1);
3987 g_variant_type_string_scan (*str, NULL, str);
3993 /* special case: NULL pointer for empty array */
3995 const GVariantType *type = (GVariantType *) *str;
3997 g_variant_type_string_scan (*str, NULL, str);
3999 if G_UNLIKELY (!g_variant_type_is_definite (type))
4000 g_error ("g_variant_new: NULL pointer given with indefinite "
4001 "array type; unable to determine which type of empty "
4002 "array to construct.");
4004 return g_variant_new_array (type, NULL, 0);
4011 value = g_variant_new_string (ptr);
4014 value = g_variant_new_string ("[Invalid UTF-8]");
4020 return g_variant_new_object_path (ptr);
4023 return g_variant_new_signature (ptr);
4031 type = g_variant_scan_convenience (str, &constant, &arrays);
4034 return g_variant_new_strv (ptr, -1);
4037 return g_variant_new_objv (ptr, -1);
4040 return g_variant_new_bytestring_array (ptr, -1);
4042 return g_variant_new_bytestring (ptr);
4046 if G_UNLIKELY (!g_variant_is_of_type (ptr, (GVariantType *) *str))
4047 g_error ("g_variant_new: expected GVariant of type `%s' but "
4048 "received value has type `%s'",
4049 g_variant_type_dup_string ((GVariantType *) *str),
4050 g_variant_get_type_string (ptr));
4052 g_variant_type_string_scan (*str, NULL, str);
4060 if G_UNLIKELY (!g_variant_type_is_basic (g_variant_get_type (ptr)))
4061 g_error ("g_variant_new: format string `?' expects basic-typed "
4062 "GVariant, but received value has type `%s'",
4063 g_variant_get_type_string (ptr));
4068 if G_UNLIKELY (!g_variant_type_is_tuple (g_variant_get_type (ptr)))
4069 g_error ("g_variant_new: format string `r` expects tuple-typed "
4070 "GVariant, but received value has type `%s'",
4071 g_variant_get_type_string (ptr));
4076 return g_variant_new_variant (ptr);
4079 g_assert_not_reached ();
4084 g_variant_valist_get_nnp (const gchar **str,
4090 g_variant_type_string_scan (*str, NULL, str);
4091 return g_variant_iter_new (value);
4095 return (gchar *) g_variant_get_string (value, NULL);
4100 return g_variant_dup_string (value, NULL);
4108 type = g_variant_scan_convenience (str, &constant, &arrays);
4113 return g_variant_get_strv (value, NULL);
4115 return g_variant_dup_strv (value, NULL);
4118 else if (type == 'o')
4121 return g_variant_get_objv (value, NULL);
4123 return g_variant_dup_objv (value, NULL);
4126 else if (arrays > 1)
4129 return g_variant_get_bytestring_array (value, NULL);
4131 return g_variant_dup_bytestring_array (value, NULL);
4137 return (gchar *) g_variant_get_bytestring (value);
4139 return g_variant_dup_bytestring (value, NULL);
4144 g_variant_type_string_scan (*str, NULL, str);
4150 return g_variant_ref (value);
4153 return g_variant_get_variant (value);
4156 g_assert_not_reached ();
4162 g_variant_valist_skip_leaf (const gchar **str,
4165 if (g_variant_format_string_is_nnp (*str))
4167 g_variant_format_string_scan (*str, NULL, str);
4168 va_arg (*app, gpointer);
4186 va_arg (*app, guint64);
4190 va_arg (*app, gdouble);
4194 g_assert_not_reached ();
4199 g_variant_valist_new_leaf (const gchar **str,
4202 if (g_variant_format_string_is_nnp (*str))
4203 return g_variant_valist_new_nnp (str, va_arg (*app, gpointer));
4208 return g_variant_new_boolean (va_arg (*app, gboolean));
4211 return g_variant_new_byte (va_arg (*app, guint));
4214 return g_variant_new_int16 (va_arg (*app, gint));
4217 return g_variant_new_uint16 (va_arg (*app, guint));
4220 return g_variant_new_int32 (va_arg (*app, gint));
4223 return g_variant_new_uint32 (va_arg (*app, guint));
4226 return g_variant_new_int64 (va_arg (*app, gint64));
4229 return g_variant_new_uint64 (va_arg (*app, guint64));
4232 return g_variant_new_handle (va_arg (*app, gint));
4235 return g_variant_new_double (va_arg (*app, gdouble));
4238 g_assert_not_reached ();
4242 /* The code below assumes this */
4243 G_STATIC_ASSERT (sizeof (gboolean) == sizeof (guint32));
4244 G_STATIC_ASSERT (sizeof (gdouble) == sizeof (guint64));
4247 g_variant_valist_get_leaf (const gchar **str,
4252 gpointer ptr = va_arg (*app, gpointer);
4256 g_variant_format_string_scan (*str, NULL, str);
4260 if (g_variant_format_string_is_nnp (*str))
4262 gpointer *nnp = (gpointer *) ptr;
4264 if (free && *nnp != NULL)
4265 g_variant_valist_free_nnp (*str, *nnp);
4270 *nnp = g_variant_valist_get_nnp (str, value);
4272 g_variant_format_string_scan (*str, NULL, str);
4282 *(gboolean *) ptr = g_variant_get_boolean (value);
4286 *(guchar *) ptr = g_variant_get_byte (value);
4290 *(gint16 *) ptr = g_variant_get_int16 (value);
4294 *(guint16 *) ptr = g_variant_get_uint16 (value);
4298 *(gint32 *) ptr = g_variant_get_int32 (value);
4302 *(guint32 *) ptr = g_variant_get_uint32 (value);
4306 *(gint64 *) ptr = g_variant_get_int64 (value);
4310 *(guint64 *) ptr = g_variant_get_uint64 (value);
4314 *(gint32 *) ptr = g_variant_get_handle (value);
4318 *(gdouble *) ptr = g_variant_get_double (value);
4327 *(guchar *) ptr = 0;
4332 *(guint16 *) ptr = 0;
4339 *(guint32 *) ptr = 0;
4345 *(guint64 *) ptr = 0;
4350 g_assert_not_reached ();
4353 /* Generic (recursive) {{{2 */
4355 g_variant_valist_skip (const gchar **str,
4358 if (g_variant_format_string_is_leaf (*str))
4359 g_variant_valist_skip_leaf (str, app);
4361 else if (**str == 'm') /* maybe */
4365 if (!g_variant_format_string_is_nnp (*str))
4366 va_arg (*app, gboolean);
4368 g_variant_valist_skip (str, app);
4370 else /* tuple, dictionary entry */
4372 g_assert (**str == '(' || **str == '{');
4374 while (**str != ')' && **str != '}')
4375 g_variant_valist_skip (str, app);
4381 g_variant_valist_new (const gchar **str,
4384 if (g_variant_format_string_is_leaf (*str))
4385 return g_variant_valist_new_leaf (str, app);
4387 if (**str == 'm') /* maybe */
4389 GVariantType *type = NULL;
4390 GVariant *value = NULL;
4394 if (g_variant_format_string_is_nnp (*str))
4396 gpointer nnp = va_arg (*app, gpointer);
4399 value = g_variant_valist_new_nnp (str, nnp);
4401 type = g_variant_format_string_scan_type (*str, NULL, str);
4405 gboolean just = va_arg (*app, gboolean);
4408 value = g_variant_valist_new (str, app);
4411 type = g_variant_format_string_scan_type (*str, NULL, NULL);
4412 g_variant_valist_skip (str, app);
4416 value = g_variant_new_maybe (type, value);
4419 g_variant_type_free (type);
4423 else /* tuple, dictionary entry */
4428 g_variant_builder_init (&b, G_VARIANT_TYPE_TUPLE);
4431 g_assert (**str == '{');
4432 g_variant_builder_init (&b, G_VARIANT_TYPE_DICT_ENTRY);
4436 while (**str != ')' && **str != '}')
4437 g_variant_builder_add_value (&b, g_variant_valist_new (str, app));
4440 return g_variant_builder_end (&b);
4445 g_variant_valist_get (const gchar **str,
4450 if (g_variant_format_string_is_leaf (*str))
4451 g_variant_valist_get_leaf (str, value, free, app);
4453 else if (**str == 'm')
4458 value = g_variant_get_maybe (value);
4460 if (!g_variant_format_string_is_nnp (*str))
4462 gboolean *ptr = va_arg (*app, gboolean *);
4465 *ptr = value != NULL;
4468 g_variant_valist_get (str, value, free, app);
4471 g_variant_unref (value);
4474 else /* tuple, dictionary entry */
4478 g_assert (**str == '(' || **str == '{');
4481 while (**str != ')' && **str != '}')
4485 GVariant *child = g_variant_get_child_value (value, index++);
4486 g_variant_valist_get (str, child, free, app);
4487 g_variant_unref (child);
4490 g_variant_valist_get (str, NULL, free, app);
4496 /* User-facing API {{{2 */
4498 * g_variant_new: (skip)
4499 * @format_string: a #GVariant format string
4500 * @...: arguments, as per @format_string
4502 * Creates a new #GVariant instance.
4504 * Think of this function as an analogue to g_strdup_printf().
4506 * The type of the created instance and the arguments that are
4507 * expected by this function are determined by @format_string. See the
4508 * section on <link linkend='gvariant-format-strings'>GVariant Format
4509 * Strings</link>. Please note that the syntax of the format string is
4510 * very likely to be extended in the future.
4512 * The first character of the format string must not be '*' '?' '@' or
4513 * 'r'; in essence, a new #GVariant must always be constructed by this
4514 * function (and not merely passed through it unmodified).
4516 * Returns: a new floating #GVariant instance
4521 g_variant_new (const gchar *format_string,
4527 g_return_val_if_fail (valid_format_string (format_string, TRUE, NULL) &&
4528 format_string[0] != '?' && format_string[0] != '@' &&
4529 format_string[0] != '*' && format_string[0] != 'r',
4532 va_start (ap, format_string);
4533 value = g_variant_new_va (format_string, NULL, &ap);
4540 * g_variant_new_va: (skip)
4541 * @format_string: a string that is prefixed with a format string
4542 * @endptr: (allow-none) (default NULL): location to store the end pointer,
4544 * @app: a pointer to a #va_list
4546 * This function is intended to be used by libraries based on
4547 * #GVariant that want to provide g_variant_new()-like functionality
4550 * The API is more general than g_variant_new() to allow a wider range
4553 * @format_string must still point to a valid format string, but it only
4554 * needs to be nul-terminated if @endptr is %NULL. If @endptr is
4555 * non-%NULL then it is updated to point to the first character past the
4556 * end of the format string.
4558 * @app is a pointer to a #va_list. The arguments, according to
4559 * @format_string, are collected from this #va_list and the list is left
4560 * pointing to the argument following the last.
4562 * These two generalisations allow mixing of multiple calls to
4563 * g_variant_new_va() and g_variant_get_va() within a single actual
4564 * varargs call by the user.
4566 * The return value will be floating if it was a newly created GVariant
4567 * instance (for example, if the format string was "(ii)"). In the case
4568 * that the format_string was '*', '?', 'r', or a format starting with
4569 * '@' then the collected #GVariant pointer will be returned unmodified,
4570 * without adding any additional references.
4572 * In order to behave correctly in all cases it is necessary for the
4573 * calling function to g_variant_ref_sink() the return result before
4574 * returning control to the user that originally provided the pointer.
4575 * At this point, the caller will have their own full reference to the
4576 * result. This can also be done by adding the result to a container,
4577 * or by passing it to another g_variant_new() call.
4579 * Returns: a new, usually floating, #GVariant
4584 g_variant_new_va (const gchar *format_string,
4585 const gchar **endptr,
4590 g_return_val_if_fail (valid_format_string (format_string, !endptr, NULL),
4592 g_return_val_if_fail (app != NULL, NULL);
4594 value = g_variant_valist_new (&format_string, app);
4597 *endptr = format_string;
4603 * g_variant_get: (skip)
4604 * @value: a #GVariant instance
4605 * @format_string: a #GVariant format string
4606 * @...: arguments, as per @format_string
4608 * Deconstructs a #GVariant instance.
4610 * Think of this function as an analogue to scanf().
4612 * The arguments that are expected by this function are entirely
4613 * determined by @format_string. @format_string also restricts the
4614 * permissible types of @value. It is an error to give a value with
4615 * an incompatible type. See the section on <link
4616 * linkend='gvariant-format-strings'>GVariant Format Strings</link>.
4617 * Please note that the syntax of the format string is very likely to be
4618 * extended in the future.
4620 * @format_string determines the C types that are used for unpacking
4621 * the values and also determines if the values are copied or borrowed,
4622 * see the section on
4623 * <link linkend='gvariant-format-strings-pointers'>GVariant Format Strings</link>.
4628 g_variant_get (GVariant *value,
4629 const gchar *format_string,
4634 g_return_if_fail (valid_format_string (format_string, TRUE, value));
4636 /* if any direct-pointer-access formats are in use, flatten first */
4637 if (strchr (format_string, '&'))
4638 g_variant_get_data (value);
4640 va_start (ap, format_string);
4641 g_variant_get_va (value, format_string, NULL, &ap);
4646 * g_variant_get_va: (skip)
4647 * @value: a #GVariant
4648 * @format_string: a string that is prefixed with a format string
4649 * @endptr: (allow-none) (default NULL): location to store the end pointer,
4651 * @app: a pointer to a #va_list
4653 * This function is intended to be used by libraries based on #GVariant
4654 * that want to provide g_variant_get()-like functionality to their
4657 * The API is more general than g_variant_get() to allow a wider range
4660 * @format_string must still point to a valid format string, but it only
4661 * need to be nul-terminated if @endptr is %NULL. If @endptr is
4662 * non-%NULL then it is updated to point to the first character past the
4663 * end of the format string.
4665 * @app is a pointer to a #va_list. The arguments, according to
4666 * @format_string, are collected from this #va_list and the list is left
4667 * pointing to the argument following the last.
4669 * These two generalisations allow mixing of multiple calls to
4670 * g_variant_new_va() and g_variant_get_va() within a single actual
4671 * varargs call by the user.
4673 * @format_string determines the C types that are used for unpacking
4674 * the values and also determines if the values are copied or borrowed,
4675 * see the section on
4676 * <link linkend='gvariant-format-strings-pointers'>GVariant Format Strings</link>.
4681 g_variant_get_va (GVariant *value,
4682 const gchar *format_string,
4683 const gchar **endptr,
4686 g_return_if_fail (valid_format_string (format_string, !endptr, value));
4687 g_return_if_fail (value != NULL);
4688 g_return_if_fail (app != NULL);
4690 /* if any direct-pointer-access formats are in use, flatten first */
4691 if (strchr (format_string, '&'))
4692 g_variant_get_data (value);
4694 g_variant_valist_get (&format_string, value, FALSE, app);
4697 *endptr = format_string;
4700 /* Varargs-enabled Utility Functions {{{1 */
4703 * g_variant_builder_add: (skp)
4704 * @builder: a #GVariantBuilder
4705 * @format_string: a #GVariant varargs format string
4706 * @...: arguments, as per @format_string
4708 * Adds to a #GVariantBuilder.
4710 * This call is a convenience wrapper that is exactly equivalent to
4711 * calling g_variant_new() followed by g_variant_builder_add_value().
4713 * This function might be used as follows:
4717 * make_pointless_dictionary (void)
4719 * GVariantBuilder *builder;
4722 * builder = g_variant_builder_new (G_VARIANT_TYPE_ARRAY);
4723 * for (i = 0; i < 16; i++)
4727 * sprintf (buf, "%d", i);
4728 * g_variant_builder_add (builder, "{is}", i, buf);
4731 * return g_variant_builder_end (builder);
4738 g_variant_builder_add (GVariantBuilder *builder,
4739 const gchar *format_string,
4745 va_start (ap, format_string);
4746 variant = g_variant_new_va (format_string, NULL, &ap);
4749 g_variant_builder_add_value (builder, variant);
4753 * g_variant_get_child: (skip)
4754 * @value: a container #GVariant
4755 * @index_: the index of the child to deconstruct
4756 * @format_string: a #GVariant format string
4757 * @...: arguments, as per @format_string
4759 * Reads a child item out of a container #GVariant instance and
4760 * deconstructs it according to @format_string. This call is
4761 * essentially a combination of g_variant_get_child_value() and
4764 * @format_string determines the C types that are used for unpacking
4765 * the values and also determines if the values are copied or borrowed,
4766 * see the section on
4767 * <link linkend='gvariant-format-strings-pointers'>GVariant Format Strings</link>.
4772 g_variant_get_child (GVariant *value,
4774 const gchar *format_string,
4780 child = g_variant_get_child_value (value, index_);
4781 g_return_if_fail (valid_format_string (format_string, TRUE, child));
4783 va_start (ap, format_string);
4784 g_variant_get_va (child, format_string, NULL, &ap);
4787 g_variant_unref (child);
4791 * g_variant_iter_next: (skip)
4792 * @iter: a #GVariantIter
4793 * @format_string: a GVariant format string
4794 * @...: the arguments to unpack the value into
4796 * Gets the next item in the container and unpacks it into the variable
4797 * argument list according to @format_string, returning %TRUE.
4799 * If no more items remain then %FALSE is returned.
4801 * All of the pointers given on the variable arguments list of this
4802 * function are assumed to point at uninitialised memory. It is the
4803 * responsibility of the caller to free all of the values returned by
4804 * the unpacking process.
4806 * See the section on <link linkend='gvariant-format-strings'>GVariant
4807 * Format Strings</link>.
4810 * <title>Memory management with g_variant_iter_next()</title>
4812 * /<!-- -->* Iterates a dictionary of type 'a{sv}' *<!-- -->/
4814 * iterate_dictionary (GVariant *dictionary)
4816 * GVariantIter iter;
4820 * g_variant_iter_init (&iter, dictionary);
4821 * while (g_variant_iter_next (&iter, "{sv}", &key, &value))
4823 * g_print ("Item '%s' has type '%s'\n", key,
4824 * g_variant_get_type_string (value));
4826 * /<!-- -->* must free data for ourselves *<!-- -->/
4827 * g_variant_unref (value);
4834 * For a solution that is likely to be more convenient to C programmers
4835 * when dealing with loops, see g_variant_iter_loop().
4837 * @format_string determines the C types that are used for unpacking
4838 * the values and also determines if the values are copied or borrowed,
4839 * see the section on
4840 * <link linkend='gvariant-format-strings-pointers'>GVariant Format Strings</link>.
4842 * Returns: %TRUE if a value was unpacked, or %FALSE if there as no value
4847 g_variant_iter_next (GVariantIter *iter,
4848 const gchar *format_string,
4853 value = g_variant_iter_next_value (iter);
4855 g_return_val_if_fail (valid_format_string (format_string, TRUE, value),
4862 va_start (ap, format_string);
4863 g_variant_valist_get (&format_string, value, FALSE, &ap);
4866 g_variant_unref (value);
4869 return value != NULL;
4873 * g_variant_iter_loop: (skip)
4874 * @iter: a #GVariantIter
4875 * @format_string: a GVariant format string
4876 * @...: the arguments to unpack the value into
4878 * Gets the next item in the container and unpacks it into the variable
4879 * argument list according to @format_string, returning %TRUE.
4881 * If no more items remain then %FALSE is returned.
4883 * On the first call to this function, the pointers appearing on the
4884 * variable argument list are assumed to point at uninitialised memory.
4885 * On the second and later calls, it is assumed that the same pointers
4886 * will be given and that they will point to the memory as set by the
4887 * previous call to this function. This allows the previous values to
4888 * be freed, as appropriate.
4890 * This function is intended to be used with a while loop as
4891 * demonstrated in the following example. This function can only be
4892 * used when iterating over an array. It is only valid to call this
4893 * function with a string constant for the format string and the same
4894 * string constant must be used each time. Mixing calls to this
4895 * function and g_variant_iter_next() or g_variant_iter_next_value() on
4896 * the same iterator causes undefined behavior.
4898 * If you break out of a such a while loop using g_variant_iter_loop() then
4899 * you must free or unreference all the unpacked values as you would with
4900 * g_variant_get(). Failure to do so will cause a memory leak.
4902 * See the section on <link linkend='gvariant-format-strings'>GVariant
4903 * Format Strings</link>.
4906 * <title>Memory management with g_variant_iter_loop()</title>
4908 * /<!-- -->* Iterates a dictionary of type 'a{sv}' *<!-- -->/
4910 * iterate_dictionary (GVariant *dictionary)
4912 * GVariantIter iter;
4916 * g_variant_iter_init (&iter, dictionary);
4917 * while (g_variant_iter_loop (&iter, "{sv}", &key, &value))
4919 * g_print ("Item '%s' has type '%s'\n", key,
4920 * g_variant_get_type_string (value));
4922 * /<!-- -->* no need to free 'key' and 'value' here *<!-- -->/
4923 * /<!-- -->* unless breaking out of this loop *<!-- -->/
4929 * For most cases you should use g_variant_iter_next().
4931 * This function is really only useful when unpacking into #GVariant or
4932 * #GVariantIter in order to allow you to skip the call to
4933 * g_variant_unref() or g_variant_iter_free().
4935 * For example, if you are only looping over simple integer and string
4936 * types, g_variant_iter_next() is definitely preferred. For string
4937 * types, use the '&' prefix to avoid allocating any memory at all (and
4938 * thereby avoiding the need to free anything as well).
4940 * @format_string determines the C types that are used for unpacking
4941 * the values and also determines if the values are copied or borrowed,
4942 * see the section on
4943 * <link linkend='gvariant-format-strings-pointers'>GVariant Format Strings</link>.
4945 * Returns: %TRUE if a value was unpacked, or %FALSE if there was no
4951 g_variant_iter_loop (GVariantIter *iter,
4952 const gchar *format_string,
4955 gboolean first_time = GVSI(iter)->loop_format == NULL;
4959 g_return_val_if_fail (first_time ||
4960 format_string == GVSI(iter)->loop_format,
4965 TYPE_CHECK (GVSI(iter)->value, G_VARIANT_TYPE_ARRAY, FALSE);
4966 GVSI(iter)->loop_format = format_string;
4968 if (strchr (format_string, '&'))
4969 g_variant_get_data (GVSI(iter)->value);
4972 value = g_variant_iter_next_value (iter);
4974 g_return_val_if_fail (!first_time ||
4975 valid_format_string (format_string, TRUE, value),
4978 va_start (ap, format_string);
4979 g_variant_valist_get (&format_string, value, !first_time, &ap);
4983 g_variant_unref (value);
4985 return value != NULL;
4988 /* Serialised data {{{1 */
4990 g_variant_deep_copy (GVariant *value)
4992 switch (g_variant_classify (value))
4994 case G_VARIANT_CLASS_MAYBE:
4995 case G_VARIANT_CLASS_ARRAY:
4996 case G_VARIANT_CLASS_TUPLE:
4997 case G_VARIANT_CLASS_DICT_ENTRY:
4998 case G_VARIANT_CLASS_VARIANT:
5000 GVariantBuilder builder;
5004 g_variant_builder_init (&builder, g_variant_get_type (value));
5005 g_variant_iter_init (&iter, value);
5007 while ((child = g_variant_iter_next_value (&iter)))
5009 g_variant_builder_add_value (&builder, g_variant_deep_copy (child));
5010 g_variant_unref (child);
5013 return g_variant_builder_end (&builder);
5016 case G_VARIANT_CLASS_BOOLEAN:
5017 return g_variant_new_boolean (g_variant_get_boolean (value));
5019 case G_VARIANT_CLASS_BYTE:
5020 return g_variant_new_byte (g_variant_get_byte (value));
5022 case G_VARIANT_CLASS_INT16:
5023 return g_variant_new_int16 (g_variant_get_int16 (value));
5025 case G_VARIANT_CLASS_UINT16:
5026 return g_variant_new_uint16 (g_variant_get_uint16 (value));
5028 case G_VARIANT_CLASS_INT32:
5029 return g_variant_new_int32 (g_variant_get_int32 (value));
5031 case G_VARIANT_CLASS_UINT32:
5032 return g_variant_new_uint32 (g_variant_get_uint32 (value));
5034 case G_VARIANT_CLASS_INT64:
5035 return g_variant_new_int64 (g_variant_get_int64 (value));
5037 case G_VARIANT_CLASS_UINT64:
5038 return g_variant_new_uint64 (g_variant_get_uint64 (value));
5040 case G_VARIANT_CLASS_HANDLE:
5041 return g_variant_new_handle (g_variant_get_handle (value));
5043 case G_VARIANT_CLASS_DOUBLE:
5044 return g_variant_new_double (g_variant_get_double (value));
5046 case G_VARIANT_CLASS_STRING:
5047 return g_variant_new_string (g_variant_get_string (value, NULL));
5049 case G_VARIANT_CLASS_OBJECT_PATH:
5050 return g_variant_new_object_path (g_variant_get_string (value, NULL));
5052 case G_VARIANT_CLASS_SIGNATURE:
5053 return g_variant_new_signature (g_variant_get_string (value, NULL));
5056 g_assert_not_reached ();
5060 * g_variant_get_normal_form:
5061 * @value: a #GVariant
5063 * Gets a #GVariant instance that has the same value as @value and is
5064 * trusted to be in normal form.
5066 * If @value is already trusted to be in normal form then a new
5067 * reference to @value is returned.
5069 * If @value is not already trusted, then it is scanned to check if it
5070 * is in normal form. If it is found to be in normal form then it is
5071 * marked as trusted and a new reference to it is returned.
5073 * If @value is found not to be in normal form then a new trusted
5074 * #GVariant is created with the same value as @value.
5076 * It makes sense to call this function if you've received #GVariant
5077 * data from untrusted sources and you want to ensure your serialised
5078 * output is definitely in normal form.
5080 * Returns: (transfer full): a trusted #GVariant
5085 g_variant_get_normal_form (GVariant *value)
5089 if (g_variant_is_normal_form (value))
5090 return g_variant_ref (value);
5092 trusted = g_variant_deep_copy (value);
5093 g_assert (g_variant_is_trusted (trusted));
5095 return g_variant_ref_sink (trusted);
5099 * g_variant_byteswap:
5100 * @value: a #GVariant
5102 * Performs a byteswapping operation on the contents of @value. The
5103 * result is that all multi-byte numeric data contained in @value is
5104 * byteswapped. That includes 16, 32, and 64bit signed and unsigned
5105 * integers as well as file handles and double precision floating point
5108 * This function is an identity mapping on any value that does not
5109 * contain multi-byte numeric data. That include strings, booleans,
5110 * bytes and containers containing only these things (recursively).
5112 * The returned value is always in normal form and is marked as trusted.
5114 * Returns: (transfer full): the byteswapped form of @value
5119 g_variant_byteswap (GVariant *value)
5121 GVariantTypeInfo *type_info;
5125 type_info = g_variant_get_type_info (value);
5127 g_variant_type_info_query (type_info, &alignment, NULL);
5130 /* (potentially) contains multi-byte numeric data */
5132 GVariantSerialised serialised;
5136 trusted = g_variant_get_normal_form (value);
5137 serialised.type_info = g_variant_get_type_info (trusted);
5138 serialised.size = g_variant_get_size (trusted);
5139 serialised.data = g_malloc (serialised.size);
5140 g_variant_store (trusted, serialised.data);
5141 g_variant_unref (trusted);
5143 g_variant_serialised_byteswap (serialised);
5145 bytes = g_bytes_new_take (serialised.data, serialised.size);
5146 new = g_variant_new_from_bytes (g_variant_get_type (value), bytes, TRUE);
5147 g_bytes_unref (bytes);
5150 /* contains no multi-byte data */
5153 return g_variant_ref_sink (new);
5157 * g_variant_new_from_data:
5158 * @type: a definite #GVariantType
5159 * @data: (array length=size) (element-type guint8): the serialised data
5160 * @size: the size of @data
5161 * @trusted: %TRUE if @data is definitely in normal form
5162 * @notify: (scope async): function to call when @data is no longer needed
5163 * @user_data: data for @notify
5165 * Creates a new #GVariant instance from serialised data.
5167 * @type is the type of #GVariant instance that will be constructed.
5168 * The interpretation of @data depends on knowing the type.
5170 * @data is not modified by this function and must remain valid with an
5171 * unchanging value until such a time as @notify is called with
5172 * @user_data. If the contents of @data change before that time then
5173 * the result is undefined.
5175 * If @data is trusted to be serialised data in normal form then
5176 * @trusted should be %TRUE. This applies to serialised data created
5177 * within this process or read from a trusted location on the disk (such
5178 * as a file installed in /usr/lib alongside your application). You
5179 * should set trusted to %FALSE if @data is read from the network, a
5180 * file in the user's home directory, etc.
5182 * If @data was not stored in this machine's native endianness, any multi-byte
5183 * numeric values in the returned variant will also be in non-native
5184 * endianness. g_variant_byteswap() can be used to recover the original values.
5186 * @notify will be called with @user_data when @data is no longer
5187 * needed. The exact time of this call is unspecified and might even be
5188 * before this function returns.
5190 * Returns: (transfer none): a new floating #GVariant of type @type
5195 g_variant_new_from_data (const GVariantType *type,
5199 GDestroyNotify notify,
5205 g_return_val_if_fail (g_variant_type_is_definite (type), NULL);
5206 g_return_val_if_fail (data != NULL || size == 0, NULL);
5209 bytes = g_bytes_new_with_free_func (data, size, notify, user_data);
5211 bytes = g_bytes_new_static (data, size);
5213 value = g_variant_new_from_bytes (type, bytes, trusted);
5214 g_bytes_unref (bytes);
5220 /* vim:set foldmethod=marker: */