1 /* GIO - GLib Input, Output and Streaming Library
2  *
3  * Copyright (C) 2006-2007 Red Hat, Inc.
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2.1 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General
16  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
17  *
18  * Author: Alexander Larsson <alexl@redhat.com>
19  */
20 
21 #include "config.h"
22 #include <stdlib.h>
23 #include <string.h>
24 
25 #include "gicon.h"
26 #include "gthemedicon.h"
27 #include "gfileicon.h"
28 #include "gemblemedicon.h"
29 #include "gbytesicon.h"
30 #include "gfile.h"
31 #include "gioerror.h"
32 #include "gioenumtypes.h"
33 #include "gvfs.h"
34 
35 #include "glibintl.h"
36 
37 
38 /* There versioning of this is implicit, version 1 would be ".1 " */
39 #define G_ICON_SERIALIZATION_MAGIC0 ". "
40 
41 /**
42  * SECTION:gicon
43  * @short_description: Interface for icons
44  * @include: gio/gio.h
45  *
46  * #GIcon is a very minimal interface for icons. It provides functions
47  * for checking the equality of two icons, hashing of icons and
48  * serializing an icon to and from strings.
49  *
50  * #GIcon does not provide the actual pixmap for the icon as this is out
51  * of GIO's scope, however implementations of #GIcon may contain the name
52  * of an icon (see #GThemedIcon), or the path to an icon (see #GLoadableIcon).
53  *
54  * To obtain a hash of a #GIcon, see g_icon_hash().
55  *
56  * To check if two #GIcons are equal, see g_icon_equal().
57  *
58  * For serializing a #GIcon, use g_icon_serialize() and
59  * g_icon_deserialize().
60  *
61  * If you want to consume #GIcon (for example, in a toolkit) you must
62  * be prepared to handle at least the three following cases:
63  * #GLoadableIcon, #GThemedIcon and #GEmblemedIcon.  It may also make
64  * sense to have fast-paths for other cases (like handling #GdkPixbuf
65  * directly, for example) but all compliant #GIcon implementations
66  * outside of GIO must implement #GLoadableIcon.
67  *
68  * If your application or library provides one or more #GIcon
69  * implementations you need to ensure that your new implementation also
70  * implements #GLoadableIcon.  Additionally, you must provide an
71  * implementation of g_icon_serialize() that gives a result that is
72  * understood by g_icon_deserialize(), yielding one of the built-in icon
73  * types.
74  **/
75 
76 typedef GIconIface GIconInterface;
G_DEFINE_INTERFACE(GIcon,g_icon,G_TYPE_OBJECT)77 G_DEFINE_INTERFACE(GIcon, g_icon, G_TYPE_OBJECT)
78 
79 static void
80 g_icon_default_init (GIconInterface *iface)
81 {
82 }
83 
84 /**
85  * g_icon_hash:
86  * @icon: (not nullable): #gconstpointer to an icon object.
87  *
88  * Gets a hash for an icon.
89  *
90  * Virtual: hash
91  * Returns: a #guint containing a hash for the @icon, suitable for
92  * use in a #GHashTable or similar data structure.
93  **/
94 guint
g_icon_hash(gconstpointer icon)95 g_icon_hash (gconstpointer icon)
96 {
97   GIconIface *iface;
98 
99   g_return_val_if_fail (G_IS_ICON (icon), 0);
100 
101   iface = G_ICON_GET_IFACE (icon);
102 
103   return (* iface->hash) ((GIcon *)icon);
104 }
105 
106 /**
107  * g_icon_equal:
108  * @icon1: (nullable): pointer to the first #GIcon.
109  * @icon2: (nullable): pointer to the second #GIcon.
110  *
111  * Checks if two icons are equal.
112  *
113  * Returns: %TRUE if @icon1 is equal to @icon2. %FALSE otherwise.
114  **/
115 gboolean
g_icon_equal(GIcon * icon1,GIcon * icon2)116 g_icon_equal (GIcon *icon1,
117 	      GIcon *icon2)
118 {
119   GIconIface *iface;
120 
121   if (icon1 == NULL && icon2 == NULL)
122     return TRUE;
123 
124   if (icon1 == NULL || icon2 == NULL)
125     return FALSE;
126 
127   if (G_TYPE_FROM_INSTANCE (icon1) != G_TYPE_FROM_INSTANCE (icon2))
128     return FALSE;
129 
130   iface = G_ICON_GET_IFACE (icon1);
131 
132   return (* iface->equal) (icon1, icon2);
133 }
134 
135 static gboolean
g_icon_to_string_tokenized(GIcon * icon,GString * s)136 g_icon_to_string_tokenized (GIcon *icon, GString *s)
137 {
138   GPtrArray *tokens;
139   gint version;
140   GIconIface *icon_iface;
141   guint i;
142 
143   g_return_val_if_fail (icon != NULL, FALSE);
144   g_return_val_if_fail (G_IS_ICON (icon), FALSE);
145 
146   icon_iface = G_ICON_GET_IFACE (icon);
147   if (icon_iface->to_tokens == NULL)
148     return FALSE;
149 
150   tokens = g_ptr_array_new ();
151   if (!icon_iface->to_tokens (icon, tokens, &version))
152     {
153       g_ptr_array_free (tokens, TRUE);
154       return FALSE;
155     }
156 
157   /* format: TypeName[.Version] <token_0> .. <token_N-1>
158      version 0 is implicit and can be omitted
159      all the tokens are url escaped to ensure they have no spaces in them */
160 
161   g_string_append (s, g_type_name_from_instance ((GTypeInstance *)icon));
162   if (version != 0)
163     g_string_append_printf (s, ".%d", version);
164 
165   for (i = 0; i < tokens->len; i++)
166     {
167       char *token;
168 
169       token = g_ptr_array_index (tokens, i);
170 
171       g_string_append_c (s, ' ');
172       /* We really only need to escape spaces here, so allow lots of otherwise reserved chars */
173       g_string_append_uri_escaped (s, token,
174 				   G_URI_RESERVED_CHARS_ALLOWED_IN_PATH, TRUE);
175 
176       g_free (token);
177     }
178 
179   g_ptr_array_free (tokens, TRUE);
180 
181   return TRUE;
182 }
183 
184 /**
185  * g_icon_to_string:
186  * @icon: a #GIcon.
187  *
188  * Generates a textual representation of @icon that can be used for
189  * serialization such as when passing @icon to a different process or
190  * saving it to persistent storage. Use g_icon_new_for_string() to
191  * get @icon back from the returned string.
192  *
193  * The encoding of the returned string is proprietary to #GIcon except
194  * in the following two cases
195  *
196  * - If @icon is a #GFileIcon, the returned string is a native path
197  *   (such as `/path/to/my icon.png`) without escaping
198  *   if the #GFile for @icon is a native file.  If the file is not
199  *   native, the returned string is the result of g_file_get_uri()
200  *   (such as `sftp://path/to/my%20icon.png`).
201  *
202  * - If @icon is a #GThemedIcon with exactly one name and no fallbacks,
203  *   the encoding is simply the name (such as `network-server`).
204  *
205  * Virtual: to_tokens
206  * Returns: (nullable): An allocated NUL-terminated UTF8 string or
207  * %NULL if @icon can't be serialized. Use g_free() to free.
208  *
209  * Since: 2.20
210  */
211 gchar *
g_icon_to_string(GIcon * icon)212 g_icon_to_string (GIcon *icon)
213 {
214   gchar *ret;
215 
216   g_return_val_if_fail (icon != NULL, NULL);
217   g_return_val_if_fail (G_IS_ICON (icon), NULL);
218 
219   ret = NULL;
220 
221   if (G_IS_FILE_ICON (icon))
222     {
223       GFile *file;
224 
225       file = g_file_icon_get_file (G_FILE_ICON (icon));
226       if (g_file_is_native (file))
227 	{
228 	  ret = g_file_get_path (file);
229 	  if (!g_utf8_validate (ret, -1, NULL))
230 	    {
231 	      g_free (ret);
232 	      ret = NULL;
233 	    }
234 	}
235       else
236         ret = g_file_get_uri (file);
237     }
238   else if (G_IS_THEMED_ICON (icon))
239     {
240       char     **names                 = NULL;
241       gboolean   use_default_fallbacks = FALSE;
242 
243       g_object_get (G_OBJECT (icon),
244                     "names",                 &names,
245                     "use-default-fallbacks", &use_default_fallbacks,
246                     NULL);
247       /* Themed icon initialized with a single name and no fallbacks. */
248       if (names != NULL &&
249 	  names[0] != NULL &&
250 	  names[0][0] != '.' && /* Allowing icons starting with dot would break G_ICON_SERIALIZATION_MAGIC0 */
251 	  g_utf8_validate (names[0], -1, NULL) && /* Only return utf8 strings */
252           names[1] == NULL &&
253           ! use_default_fallbacks)
254 	ret = g_strdup (names[0]);
255 
256       g_strfreev (names);
257     }
258 
259   if (ret == NULL)
260     {
261       GString *s;
262 
263       s = g_string_new (G_ICON_SERIALIZATION_MAGIC0);
264 
265       if (g_icon_to_string_tokenized (icon, s))
266 	ret = g_string_free (s, FALSE);
267       else
268 	g_string_free (s, TRUE);
269     }
270 
271   return ret;
272 }
273 
274 static GIcon *
g_icon_new_from_tokens(char ** tokens,GError ** error)275 g_icon_new_from_tokens (char   **tokens,
276 			GError **error)
277 {
278   GIcon *icon;
279   char *typename, *version_str;
280   GType type;
281   gpointer klass;
282   GIconIface *icon_iface;
283   gint version;
284   char *endp;
285   int num_tokens;
286   int i;
287 
288   icon = NULL;
289   klass = NULL;
290 
291   num_tokens = g_strv_length (tokens);
292 
293   if (num_tokens < 1)
294     {
295       g_set_error (error,
296                    G_IO_ERROR,
297                    G_IO_ERROR_INVALID_ARGUMENT,
298                    _("Wrong number of tokens (%d)"),
299                    num_tokens);
300       goto out;
301     }
302 
303   typename = tokens[0];
304   version_str = strchr (typename, '.');
305   if (version_str)
306     {
307       *version_str = 0;
308       version_str += 1;
309     }
310 
311 
312   type = g_type_from_name (tokens[0]);
313   if (type == 0)
314     {
315       g_set_error (error,
316                    G_IO_ERROR,
317                    G_IO_ERROR_INVALID_ARGUMENT,
318                    _("No type for class name %s"),
319                    tokens[0]);
320       goto out;
321     }
322 
323   if (!g_type_is_a (type, G_TYPE_ICON))
324     {
325       g_set_error (error,
326                    G_IO_ERROR,
327                    G_IO_ERROR_INVALID_ARGUMENT,
328                    _("Type %s does not implement the GIcon interface"),
329                    tokens[0]);
330       goto out;
331     }
332 
333   klass = g_type_class_ref (type);
334   if (klass == NULL)
335     {
336       g_set_error (error,
337                    G_IO_ERROR,
338                    G_IO_ERROR_INVALID_ARGUMENT,
339                    _("Type %s is not classed"),
340                    tokens[0]);
341       goto out;
342     }
343 
344   version = 0;
345   if (version_str)
346     {
347       version = strtol (version_str, &endp, 10);
348       if (endp == NULL || *endp != '\0')
349 	{
350 	  g_set_error (error,
351 		       G_IO_ERROR,
352 		       G_IO_ERROR_INVALID_ARGUMENT,
353 		       _("Malformed version number: %s"),
354 		       version_str);
355 	  goto out;
356 	}
357     }
358 
359   icon_iface = g_type_interface_peek (klass, G_TYPE_ICON);
360   g_assert (icon_iface != NULL);
361 
362   if (icon_iface->from_tokens == NULL)
363     {
364       g_set_error (error,
365                    G_IO_ERROR,
366                    G_IO_ERROR_INVALID_ARGUMENT,
367                    _("Type %s does not implement from_tokens() on the GIcon interface"),
368                    tokens[0]);
369       goto out;
370     }
371 
372   for (i = 1;  i < num_tokens; i++)
373     {
374       char *escaped;
375 
376       escaped = tokens[i];
377       tokens[i] = g_uri_unescape_string (escaped, NULL);
378       g_free (escaped);
379     }
380 
381   icon = icon_iface->from_tokens (tokens + 1, num_tokens - 1, version, error);
382 
383  out:
384   if (klass != NULL)
385     g_type_class_unref (klass);
386   return icon;
387 }
388 
389 static void
ensure_builtin_icon_types(void)390 ensure_builtin_icon_types (void)
391 {
392   g_type_ensure (G_TYPE_THEMED_ICON);
393   g_type_ensure (G_TYPE_FILE_ICON);
394   g_type_ensure (G_TYPE_EMBLEMED_ICON);
395   g_type_ensure (G_TYPE_EMBLEM);
396 }
397 
398 /* handles the 'simple' cases: GFileIcon and GThemedIcon */
399 static GIcon *
g_icon_new_for_string_simple(const gchar * str)400 g_icon_new_for_string_simple (const gchar *str)
401 {
402   gchar *scheme;
403   GIcon *icon;
404 
405   if (str[0] == '.')
406     return NULL;
407 
408   /* handle special GFileIcon and GThemedIcon cases */
409   scheme = g_uri_parse_scheme (str);
410   if (scheme != NULL || str[0] == '/' || str[0] == G_DIR_SEPARATOR)
411     {
412       GFile *location;
413       location = g_file_new_for_commandline_arg (str);
414       icon = g_file_icon_new (location);
415       g_object_unref (location);
416     }
417   else
418     icon = g_themed_icon_new (str);
419 
420   g_free (scheme);
421 
422   return icon;
423 }
424 
425 /**
426  * g_icon_new_for_string:
427  * @str: A string obtained via g_icon_to_string().
428  * @error: Return location for error.
429  *
430  * Generate a #GIcon instance from @str. This function can fail if
431  * @str is not valid - see g_icon_to_string() for discussion.
432  *
433  * If your application or library provides one or more #GIcon
434  * implementations you need to ensure that each #GType is registered
435  * with the type system prior to calling g_icon_new_for_string().
436  *
437  * Returns: (transfer full): An object implementing the #GIcon
438  *          interface or %NULL if @error is set.
439  *
440  * Since: 2.20
441  **/
442 GIcon *
g_icon_new_for_string(const gchar * str,GError ** error)443 g_icon_new_for_string (const gchar   *str,
444                        GError       **error)
445 {
446   GIcon *icon = NULL;
447 
448   g_return_val_if_fail (str != NULL, NULL);
449 
450   icon = g_icon_new_for_string_simple (str);
451   if (icon)
452     return icon;
453 
454   ensure_builtin_icon_types ();
455 
456   if (g_str_has_prefix (str, G_ICON_SERIALIZATION_MAGIC0))
457     {
458       gchar **tokens;
459 
460       /* handle tokenized encoding */
461       tokens = g_strsplit (str + sizeof (G_ICON_SERIALIZATION_MAGIC0) - 1, " ", 0);
462       icon = g_icon_new_from_tokens (tokens, error);
463       g_strfreev (tokens);
464     }
465   else
466     g_set_error_literal (error,
467                          G_IO_ERROR,
468                          G_IO_ERROR_INVALID_ARGUMENT,
469                          _("Can’t handle the supplied version of the icon encoding"));
470 
471   return icon;
472 }
473 
474 static GEmblem *
g_icon_deserialize_emblem(GVariant * value)475 g_icon_deserialize_emblem (GVariant *value)
476 {
477   GVariant *emblem_metadata;
478   GVariant *emblem_data;
479   const gchar *origin_nick;
480   GIcon *emblem_icon;
481   GEmblem *emblem;
482 
483   g_variant_get (value, "(v@a{sv})", &emblem_data, &emblem_metadata);
484 
485   emblem = NULL;
486 
487   emblem_icon = g_icon_deserialize (emblem_data);
488   if (emblem_icon != NULL)
489     {
490       /* Check if we should create it with an origin. */
491       if (g_variant_lookup (emblem_metadata, "origin", "&s", &origin_nick))
492         {
493           GEnumClass *origin_class;
494           GEnumValue *origin_value;
495 
496           origin_class = g_type_class_ref (G_TYPE_EMBLEM_ORIGIN);
497           origin_value = g_enum_get_value_by_nick (origin_class, origin_nick);
498           if (origin_value)
499             emblem = g_emblem_new_with_origin (emblem_icon, origin_value->value);
500           g_type_class_unref (origin_class);
501         }
502 
503       /* We didn't create it with an origin, so do it without. */
504       if (emblem == NULL)
505         emblem = g_emblem_new (emblem_icon);
506 
507       g_object_unref (emblem_icon);
508     }
509 
510   g_variant_unref (emblem_metadata);
511   g_variant_unref (emblem_data);
512 
513   return emblem;
514 }
515 
516 static GIcon *
g_icon_deserialize_emblemed(GVariant * value)517 g_icon_deserialize_emblemed (GVariant *value)
518 {
519   GVariantIter *emblems;
520   GVariant *icon_data;
521   GIcon *main_icon;
522   GIcon *icon;
523 
524   g_variant_get (value, "(va(va{sv}))", &icon_data, &emblems);
525   main_icon = g_icon_deserialize (icon_data);
526 
527   if (main_icon)
528     {
529       GVariant *emblem_data;
530 
531       icon = g_emblemed_icon_new (main_icon, NULL);
532 
533       while ((emblem_data = g_variant_iter_next_value (emblems)))
534         {
535           GEmblem *emblem;
536 
537           emblem = g_icon_deserialize_emblem (emblem_data);
538 
539           if (emblem)
540             {
541               g_emblemed_icon_add_emblem (G_EMBLEMED_ICON (icon), emblem);
542               g_object_unref (emblem);
543             }
544 
545           g_variant_unref (emblem_data);
546         }
547 
548       g_object_unref (main_icon);
549     }
550   else
551     icon = NULL;
552 
553   g_variant_iter_free (emblems);
554   g_variant_unref (icon_data);
555 
556   return icon;
557 }
558 
559 /**
560  * g_icon_deserialize:
561  * @value: (transfer none): a #GVariant created with g_icon_serialize()
562  *
563  * Deserializes a #GIcon previously serialized using g_icon_serialize().
564  *
565  * Returns: (nullable) (transfer full): a #GIcon, or %NULL when deserialization fails.
566  *
567  * Since: 2.38
568  */
569 GIcon *
g_icon_deserialize(GVariant * value)570 g_icon_deserialize (GVariant *value)
571 {
572   const gchar *tag;
573   GVariant *val;
574   GIcon *icon;
575 
576   g_return_val_if_fail (value != NULL, NULL);
577   g_return_val_if_fail (g_variant_is_of_type (value, G_VARIANT_TYPE_STRING) ||
578                         g_variant_is_of_type (value, G_VARIANT_TYPE ("(sv)")), NULL);
579 
580   /* Handle some special cases directly so that people can hard-code
581    * stuff into GMenuModel xml files without resorting to using GVariant
582    * text format to describe one of the explicitly-tagged possibilities
583    * below.
584    */
585   if (g_variant_is_of_type (value, G_VARIANT_TYPE_STRING))
586     return g_icon_new_for_string_simple (g_variant_get_string (value, NULL));
587 
588   /* Otherwise, use the tagged union format */
589   g_variant_get (value, "(&sv)", &tag, &val);
590 
591   icon = NULL;
592 
593   if (g_str_equal (tag, "file") && g_variant_is_of_type (val, G_VARIANT_TYPE_STRING))
594     {
595       GFile *file;
596 
597       file = g_file_new_for_commandline_arg (g_variant_get_string (val, NULL));
598       icon = g_file_icon_new (file);
599       g_object_unref (file);
600     }
601   else if (g_str_equal (tag, "themed") && g_variant_is_of_type (val, G_VARIANT_TYPE_STRING_ARRAY))
602     {
603       const gchar **names;
604       gsize size;
605 
606       names = g_variant_get_strv (val, &size);
607       icon = g_themed_icon_new_from_names ((gchar **) names, size);
608       g_free (names);
609     }
610   else if (g_str_equal (tag, "bytes") && g_variant_is_of_type (val, G_VARIANT_TYPE_BYTESTRING))
611     {
612       GBytes *bytes;
613 
614       bytes = g_variant_get_data_as_bytes (val);
615       icon = g_bytes_icon_new (bytes);
616       g_bytes_unref (bytes);
617     }
618   else if (g_str_equal (tag, "emblem") && g_variant_is_of_type (val, G_VARIANT_TYPE ("(va{sv})")))
619     {
620       GEmblem *emblem;
621 
622       emblem = g_icon_deserialize_emblem (val);
623       if (emblem)
624         icon = G_ICON (emblem);
625     }
626   else if (g_str_equal (tag, "emblemed") && g_variant_is_of_type (val, G_VARIANT_TYPE ("(va(va{sv}))")))
627     {
628       icon = g_icon_deserialize_emblemed (val);
629     }
630   else if (g_str_equal (tag, "gvfs"))
631     {
632       GVfsClass *class;
633       GVfs *vfs;
634 
635       vfs = g_vfs_get_default ();
636       class = G_VFS_GET_CLASS (vfs);
637       if (class->deserialize_icon)
638         icon = (* class->deserialize_icon) (vfs, val);
639     }
640 
641   g_variant_unref (val);
642 
643   return icon;
644 }
645 
646 /**
647  * g_icon_serialize:
648  * @icon: a #GIcon
649  *
650  * Serializes a #GIcon into a #GVariant. An equivalent #GIcon can be retrieved
651  * back by calling g_icon_deserialize() on the returned value.
652  * As serialization will avoid using raw icon data when possible, it only
653  * makes sense to transfer the #GVariant between processes on the same machine,
654  * (as opposed to over the network), and within the same file system namespace.
655  *
656  * Returns: (nullable) (transfer full): a #GVariant, or %NULL when serialization fails. The #GVariant will not be floating.
657  *
658  * Since: 2.38
659  */
660 GVariant *
g_icon_serialize(GIcon * icon)661 g_icon_serialize (GIcon *icon)
662 {
663   GIconInterface *iface;
664   GVariant *result;
665 
666   iface = G_ICON_GET_IFACE (icon);
667 
668   if (!iface->serialize)
669     {
670       g_critical ("g_icon_serialize() on icon type '%s' is not implemented", G_OBJECT_TYPE_NAME (icon));
671       return NULL;
672     }
673 
674   result = (* iface->serialize) (icon);
675 
676   if (result)
677     {
678       g_variant_take_ref (result);
679 
680       if (!g_variant_is_of_type (result, G_VARIANT_TYPE ("(sv)")))
681         {
682           g_critical ("g_icon_serialize() on icon type '%s' returned GVariant of type '%s' but it must return "
683                       "one with type '(sv)'", G_OBJECT_TYPE_NAME (icon), g_variant_get_type_string (result));
684           g_variant_unref (result);
685           result = NULL;
686         }
687     }
688 
689   return result;
690 }
691