gio/gcontenttype.c

   1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
   2
   3 /* GIO - GLib Input, Output and Streaming Library
   4  *
   5  * Copyright (C) 2006-2007 Red Hat, Inc.
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General
  18  * Public License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  *
  22  * Author: Alexander Larsson <alexl@redhat.com>
  23  */
  24
  25 #include "config.h"
  26 #include <sys/types.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <stdio.h>
  30 #include "gcontenttypeprivate.h"
  31 #include "gthemedicon.h"
  32 #include "gicon.h"
  33 #include "gfile.h"
  34 #include "gfileenumerator.h"
  35 #include "gfileinfo.h"
  36 #include "glibintl.h"
  37
  38 #include "gioalias.h"
  39
  40 /**
  41  * SECTION:gcontenttype
  42  * @short_description: Platform-specific content typing
  43  * @include: gio/gio.h
  44  *
  45  * A content type is a platform specific string that defines the type
  46  * of a file. On unix it is a mime type, on win32 it is an extension string
  47  * like ".doc", ".txt" or a percieved string like "audio". Such strings
  48  * can be looked up in the registry at HKEY_CLASSES_ROOT.
  49  **/
  50
  51 #ifdef G_OS_WIN32
  52
  53 #include <windows.h>
  54
  55 static char *
  56 get_registry_classes_key (const char    *subdir,
  57                           const wchar_t *key_name)
  58 {
  59   wchar_t *wc_key;
  60   HKEY reg_key = NULL;
  61   DWORD key_type;
  62   DWORD nbytes;
  63   char *value_utf8;
  64
  65   value_utf8 = NULL;
  66
  67   nbytes = 0;
  68   wc_key = g_utf8_to_utf16 (subdir, -1, NULL, NULL, NULL);
  69   if (RegOpenKeyExW (HKEY_CLASSES_ROOT, wc_key, 0,
  70                      KEY_QUERY_VALUE, &reg_key) == ERROR_SUCCESS &&
  71       RegQueryValueExW (reg_key, key_name, 0,
  72                         &key_type, NULL, &nbytes) == ERROR_SUCCESS &&
  73       (key_type == REG_SZ || key_type == REG_EXPAND_SZ))
  74     {
  75       wchar_t *wc_temp = g_new (wchar_t, (nbytes+1)/2 + 1);
  76       RegQueryValueExW (reg_key, key_name, 0,
  77                         &key_type, (LPBYTE) wc_temp, &nbytes);
  78       wc_temp[nbytes/2] = '\0';
  79       if (key_type == REG_EXPAND_SZ)
  80         {
  81           wchar_t dummy[1];
  82           int len = ExpandEnvironmentStringsW (wc_temp, dummy, 1);
  83           if (len > 0)
  84             {
  85               wchar_t *wc_temp_expanded = g_new (wchar_t, len);
  86               if (ExpandEnvironmentStringsW (wc_temp, wc_temp_expanded, len) == len)
  87                 value_utf8 = g_utf16_to_utf8 (wc_temp_expanded, -1, NULL, NULL, NULL);
  88               g_free (wc_temp_expanded);
  89             }
  90         }
  91       else
  92         {
  93           value_utf8 = g_utf16_to_utf8 (wc_temp, -1, NULL, NULL, NULL);
  94         }
  95       g_free (wc_temp);
  96
  97     }
  98   g_free (wc_key);
  99
 100   if (reg_key != NULL)
 101     RegCloseKey (reg_key);
 102
 103   return value_utf8;
 104 }
 105
 106 gboolean
 107 g_content_type_equals (const char *type1,
 108                        const char *type2)
 109 {
 110   char *progid1, *progid2;
 111   gboolean res;
 112
 113   g_return_val_if_fail (type1 != NULL, FALSE);
 114   g_return_val_if_fail (type2 != NULL, FALSE);
 115
 116   if (g_ascii_strcasecmp (type1, type2) == 0)
 117     return TRUE;
 118
 119   res = FALSE;
 120   progid1 = get_registry_classes_key (type1, NULL);
 121   progid2 = get_registry_classes_key (type2, NULL);
 122   if (progid1 != NULL && progid2 != NULL &&
 123       strcmp (progid1, progid2) == 0)
 124     res = TRUE;
 125   g_free (progid1);
 126   g_free (progid2);
 127
 128   return res;
 129 }
 130
 131 gboolean
 132 g_content_type_is_a (const char *type,
 133                      const char *supertype)
 134 {
 135   gboolean res;
 136   char *value_utf8;
 137
 138   g_return_val_if_fail (type != NULL, FALSE);
 139   g_return_val_if_fail (supertype != NULL, FALSE);
 140
 141   if (g_content_type_equals (type, supertype))
 142     return TRUE;
 143
 144   res = FALSE;
 145   value_utf8 = get_registry_classes_key (type, L"PerceivedType");
 146   if (value_utf8 && strcmp (value_utf8, supertype) == 0)
 147     res = TRUE;
 148   g_free (value_utf8);
 149
 150   return res;
 151 }
 152
 153 gboolean
 154 g_content_type_is_unknown (const char *type)
 155 {
 156   g_return_val_if_fail (type != NULL, FALSE);
 157
 158   return strcmp ("*", type) == 0;
 159 }
 160
 161 char *
 162 g_content_type_get_description (const char *type)
 163 {
 164   char *progid;
 165   char *description;
 166
 167   g_return_val_if_fail (type != NULL, NULL);
 168
 169   progid = get_registry_classes_key (type, NULL);
 170   if (progid)
 171     {
 172       description = get_registry_classes_key (progid, NULL);
 173       g_free (progid);
 174
 175       if (description)
 176         return description;
 177     }
 178
 179   if (g_content_type_is_unknown (type))
 180     return g_strdup (_("Unknown type"));
 181   return g_strdup_printf (_("%s filetype"), type);
 182 }
 183
 184 char *
 185 g_content_type_get_mime_type (const char *type)
 186 {
 187   char *mime;
 188
 189   g_return_val_if_fail (type != NULL, NULL);
 190
 191   mime = get_registry_classes_key (type, L"Content Type");
 192   if (mime)
 193     return mime;
 194   else if (g_content_type_is_unknown (type))
 195     return g_strdup ("application/octet-stream");
 196   else if (*type == '.')
 197     return g_strdup_printf ("application/x-ext-%s", type+1);
 198   /* TODO: Map "image" to "image/ *", etc? */
 199
 200   return g_strdup ("application/octet-stream");
 201 }
 202
 203 G_LOCK_DEFINE_STATIC (_type_icons);
 204 static GHashTable *_type_icons = NULL;
 205
 206 GIcon *
 207 g_content_type_get_icon (const char *type)
 208 {
 209   GIcon *themed_icon;
 210   char *name = NULL;
 211
 212   g_return_val_if_fail (type != NULL, NULL);
 213
 214   /* In the Registry icons are the default value of
 215      HKEY_CLASSES_ROOT\<progid>\DefaultIcon with typical values like:
 216      <type>: <value>
 217      REG_EXPAND_SZ: %SystemRoot%\System32\Wscript.exe,3
 218      REG_SZ: shimgvw.dll,3
 219   */
 220   G_LOCK (_type_icons);
 221   if (!_type_icons)
 222     _type_icons = g_hash_table_new (g_str_hash, g_str_equal);
 223   name = g_hash_table_lookup (_type_icons, type);
 224   if (!name && type[0] == '.')
 225     {
 226       /* double lookup by extension */
 227       gchar *key = get_registry_classes_key (type, NULL);
 228       if (!key)
 229         key = g_strconcat (type+1, "file\\DefaultIcon", NULL);
 230       else
 231         {
 232           gchar *key2 = g_strconcat (key, "\\DefaultIcon", NULL);
 233           g_free (key);
 234           key = key2;
 235         }
 236       name = get_registry_classes_key (key, NULL);
 237       if (name && strcmp (name, "%1") == 0)
 238         {
 239           g_free (name);
 240           name = NULL;
 241         }
 242       if (name)
 243         g_hash_table_insert (_type_icons, g_strdup (type), g_strdup (name));
 244       g_free (key);
 245     }
 246
 247   /* icon-name similar to how it was with gtk-2-12 */
 248   if (name)
 249     {
 250       themed_icon = g_themed_icon_new (name);
 251     }
 252   else
 253     {
 254       /* if not found an icon fall back to gtk-builtins */
 255       name = strcmp (type, "inode/directory") == 0 ? "gtk-directory" :
 256                            g_content_type_can_be_executable (type) ? "gtk-execute" : "gtk-file";
 257       g_hash_table_insert (_type_icons, g_strdup (type), g_strdup (name));
 258       themed_icon = g_themed_icon_new_with_default_fallbacks (name);
 259     }
 260   G_UNLOCK (_type_icons);
 261
 262   return G_ICON (themed_icon);
 263 }
 264
 265 gboolean
 266 g_content_type_can_be_executable (const char *type)
 267 {
 268   g_return_val_if_fail (type != NULL, FALSE);
 269
 270   if (strcmp (type, ".exe") == 0 ||
 271       strcmp (type, ".com") == 0 ||
 272       strcmp (type, ".bat") == 0)
 273     return TRUE;
 274
 275   /* TODO: Also look at PATHEXT, which lists the extensions for
 276    * "scripts" in addition to those for true binary executables.
 277    *
 278    * (PATHEXT=.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH for me
 279    * right now, for instance). And in a sense, all associated file
 280    * types are "executable" on Windows... You can just type foo.jpg as
 281    * a command name in cmd.exe, and it will run the application
 282    * associated with .jpg. Hard to say what this API actually means
 283    * with "executable".
 284    */
 285
 286   return FALSE;
 287 }
 288
 289 static gboolean
 290 looks_like_text (const guchar *data,
 291                  gsize         data_size)
 292 {
 293   gsize i;
 294   guchar c;
 295   for (i = 0; i < data_size; i++)
 296     {
 297       c = data[i];
 298       if (g_ascii_iscntrl (c) && !g_ascii_isspace (c))
 299         return FALSE;
 300     }
 301   return TRUE;
 302 }
 303
 304 char *
 305 g_content_type_from_mime_type (const char *mime_type)
 306 {
 307   char *key, *content_type;
 308
 309   g_return_val_if_fail (mime_type != NULL, NULL);
 310
 311   key = g_strconcat ("MIME\\DataBase\\Content Type\\", mime_type, NULL);
 312   content_type = get_registry_classes_key (key, L"Extension");
 313   g_free (key);
 314
 315   return content_type;
 316 }
 317
 318 char *
 319 g_content_type_guess (const char   *filename,
 320                       const guchar *data,
 321                       gsize         data_size,
 322                       gboolean     *result_uncertain)
 323 {
 324   char *basename;
 325   char *type;
 326   char *dot;
 327
 328   type = NULL;
 329
 330   if (filename)
 331     {
 332       basename = g_path_get_basename (filename);
 333       dot = strrchr (basename, '.');
 334       if (dot)
 335         type = g_strdup (dot);
 336       g_free (basename);
 337     }
 338
 339   if (type)
 340     return type;
 341
 342   if (data && looks_like_text (data, data_size))
 343     return g_strdup (".txt");
 344
 345   return g_strdup ("*");
 346 }
 347
 348 GList *
 349 g_content_types_get_registered (void)
 350 {
 351   DWORD index;
 352   wchar_t keyname[256];
 353   DWORD key_len;
 354   char *key_utf8;
 355   GList *types;
 356
 357   types = NULL;
 358   index = 0;
 359   key_len = 256;
 360   while (RegEnumKeyExW(HKEY_CLASSES_ROOT,
 361                        index,
 362                        keyname,
 363                        &key_len,
 364                        NULL,
 365                        NULL,
 366                        NULL,
 367                        NULL) == ERROR_SUCCESS)
 368     {
 369       key_utf8 = g_utf16_to_utf8 (keyname, -1, NULL, NULL, NULL);
 370       if (key_utf8)
 371         {
 372           if (*key_utf8 == '.')
 373             types = g_list_prepend (types, key_utf8);
 374           else
 375             g_free (key_utf8);
 376         }
 377       index++;
 378       key_len = 256;
 379     }
 380
 381   return g_list_reverse (types);
 382 }
 383
 384 char **
 385 g_content_type_guess_for_tree (GFile *root)
 386 {
 387   /* FIXME: implement */
 388   return NULL;
 389 }
 390
 391 #else /* !G_OS_WIN32 - Unix specific version */
 392
 393 #include <dirent.h>
 394
 395 #define XDG_PREFIX _gio_xdg
 396 #include "xdgmime/xdgmime.h"
 397
 398 /* We lock this mutex whenever we modify global state in this module.  */
 399 G_LOCK_DEFINE_STATIC (gio_xdgmime);
 400
 401 gsize
 402 _g_unix_content_type_get_sniff_len (void)
 403 {
 404   gsize size;
 405
 406   G_LOCK (gio_xdgmime);
 407   size = xdg_mime_get_max_buffer_extents ();
 408   G_UNLOCK (gio_xdgmime);
 409
 410   return size;
 411 }
 412
 413 char *
 414 _g_unix_content_type_unalias (const char *type)
 415 {
 416   char *res;
 417
 418   G_LOCK (gio_xdgmime);
 419   res = g_strdup (xdg_mime_unalias_mime_type (type));
 420   G_UNLOCK (gio_xdgmime);
 421
 422   return res;
 423 }
 424
 425 char **
 426 _g_unix_content_type_get_parents (const char *type)
 427 {
 428   const char *umime;
 429   char **parents;
 430   GPtrArray *array;
 431   int i;
 432
 433   array = g_ptr_array_new ();
 434
 435   G_LOCK (gio_xdgmime);
 436
 437   umime = xdg_mime_unalias_mime_type (type);
 438
 439   g_ptr_array_add (array, g_strdup (umime));
 440
 441   parents = xdg_mime_list_mime_parents (umime);
 442   for (i = 0; parents && parents[i] != NULL; i++)
 443     g_ptr_array_add (array, g_strdup (parents[i]));
 444
 445   free (parents);
 446
 447   G_UNLOCK (gio_xdgmime);
 448
 449   g_ptr_array_add (array, NULL);
 450
 451   return (char **)g_ptr_array_free (array, FALSE);
 452 }
 453
 454 /**
 455  * g_content_type_equals:
 456  * @type1: a content type string.
 457  * @type2: a content type string.
 458  *
 459  * Compares two content types for equality.
 460  *
 461  * Returns: %TRUE if the two strings are identical or equivalent,
 462  * %FALSE otherwise.
 463  **/
 464 gboolean
 465 g_content_type_equals (const char *type1,
 466                        const char *type2)
 467 {
 468   gboolean res;
 469
 470   g_return_val_if_fail (type1 != NULL, FALSE);
 471   g_return_val_if_fail (type2 != NULL, FALSE);
 472
 473   G_LOCK (gio_xdgmime);
 474   res = xdg_mime_mime_type_equal (type1, type2);
 475   G_UNLOCK (gio_xdgmime);
 476
 477   return res;
 478 }
 479
 480 /**
 481  * g_content_type_is_a:
 482  * @type: a content type string.
 483  * @supertype: a string.
 484  *
 485  * Determines if @type is a subset of @supertype.
 486  *
 487  * Returns: %TRUE if @type is a kind of @supertype,
 488  * %FALSE otherwise.
 489  **/
 490 gboolean
 491 g_content_type_is_a (const char *type,
 492                      const char *supertype)
 493 {
 494   gboolean res;
 495
 496   g_return_val_if_fail (type != NULL, FALSE);
 497   g_return_val_if_fail (supertype != NULL, FALSE);
 498
 499   G_LOCK (gio_xdgmime);
 500   res = xdg_mime_mime_type_subclass (type, supertype);
 501   G_UNLOCK (gio_xdgmime);
 502
 503   return res;
 504 }
 505
 506 /**
 507  * g_content_type_is_unknown:
 508  * @type: a content type string.
 509  *
 510  * Checks if the content type is the generic "unknown" type.
 511  * On unix this is the "application/octet-stream" mimetype,
 512  * while on win32 it is "*".
 513  *
 514  * Returns: %TRUE if the type is the unknown type.
 515  **/
 516 gboolean
 517 g_content_type_is_unknown (const char *type)
 518 {
 519   g_return_val_if_fail (type != NULL, FALSE);
 520
 521   return strcmp (XDG_MIME_TYPE_UNKNOWN, type) == 0;
 522 }
 523
 524
 525 typedef enum {
 526   MIME_TAG_TYPE_OTHER,
 527   MIME_TAG_TYPE_COMMENT
 528 } MimeTagType;
 529
 530 typedef struct {
 531   int current_type;
 532   int current_lang_level;
 533   int comment_lang_level;
 534   char *comment;
 535 } MimeParser;
 536
 537
 538 static int
 539 language_level (const char *lang)
 540 {
 541   const char * const *lang_list;
 542   int i;
 543
 544   /* The returned list is sorted from most desirable to least
 545      desirable and always contains the default locale "C". */
 546   lang_list = g_get_language_names ();
 547
 548   for (i = 0; lang_list[i]; i++)
 549     if (strcmp (lang_list[i], lang) == 0)
 550       return 1000-i;
 551
 552   return 0;
 553 }
 554
 555 static void
 556 mime_info_start_element (GMarkupParseContext  *context,
 557                          const gchar          *element_name,
 558                          const gchar         **attribute_names,
 559                          const gchar         **attribute_values,
 560                          gpointer              user_data,
 561                          GError              **error)
 562 {
 563   int i;
 564   const char *lang;
 565   MimeParser *parser = user_data;
 566
 567   if (strcmp (element_name, "comment") == 0)
 568     {
 569       lang = "C";
 570       for (i = 0; attribute_names[i]; i++)
 571         if (strcmp (attribute_names[i], "xml:lang") == 0)
 572           {
 573             lang = attribute_values[i];
 574             break;
 575           }
 576
 577       parser->current_lang_level = language_level (lang);
 578       parser->current_type = MIME_TAG_TYPE_COMMENT;
 579     }
 580   else
 581     parser->current_type = MIME_TAG_TYPE_OTHER;
 582
 583 }
 584
 585 static void
 586 mime_info_end_element (GMarkupParseContext  *context,
 587                        const gchar          *element_name,
 588                        gpointer              user_data,
 589                        GError              **error)
 590 {
 591   MimeParser *parser = user_data;
 592
 593   parser->current_type = MIME_TAG_TYPE_OTHER;
 594 }
 595
 596 static void
 597 mime_info_text (GMarkupParseContext  *context,
 598                 const gchar          *text,
 599                 gsize                 text_len,
 600                 gpointer              user_data,
 601                 GError              **error)
 602 {
 603   MimeParser *parser = user_data;
 604
 605   if (parser->current_type == MIME_TAG_TYPE_COMMENT &&
 606       parser->current_lang_level > parser->comment_lang_level)
 607     {
 608       g_free (parser->comment);
 609       parser->comment = g_strndup (text, text_len);
 610       parser->comment_lang_level = parser->current_lang_level;
 611     }
 612 }
 613
 614 static char *
 615 load_comment_for_mime_helper (const char *dir,
 616                               const char *basename)
 617 {
 618   GMarkupParseContext *context;
 619   char *filename, *data;
 620   gsize len;
 621   gboolean res;
 622   MimeParser parse_data = {0};
 623   GMarkupParser parser = {
 624     mime_info_start_element,
 625     mime_info_end_element,
 626     mime_info_text
 627   };
 628
 629   filename = g_build_filename (dir, "mime", basename, NULL);
 630
 631   res = g_file_get_contents (filename,  &data,  &len,  NULL);
 632   g_free (filename);
 633   if (!res)
 634     return NULL;
 635
 636   context = g_markup_parse_context_new   (&parser, 0, &parse_data, NULL);
 637   res = g_markup_parse_context_parse (context, data, len, NULL);
 638   g_free (data);
 639   g_markup_parse_context_free (context);
 640
 641   if (!res)
 642     return NULL;
 643
 644   return parse_data.comment;
 645 }
 646
 647
 648 static char *
 649 load_comment_for_mime (const char *mimetype)
 650 {
 651   const char * const* dirs;
 652   char *basename;
 653   char *comment;
 654   int i;
 655
 656   basename = g_strdup_printf ("%s.xml", mimetype);
 657
 658   comment = load_comment_for_mime_helper (g_get_user_data_dir (), basename);
 659   if (comment)
 660     {
 661       g_free (basename);
 662       return comment;
 663     }
 664
 665   dirs = g_get_system_data_dirs ();
 666
 667   for (i = 0; dirs[i] != NULL; i++)
 668     {
 669       comment = load_comment_for_mime_helper (dirs[i], basename);
 670       if (comment)
 671         {
 672           g_free (basename);
 673           return comment;
 674         }
 675     }
 676   g_free (basename);
 677
 678   return g_strdup_printf (_("%s type"), mimetype);
 679 }
 680
 681 /**
 682  * g_content_type_get_description:
 683  * @type: a content type string.
 684  *
 685  * Gets the human readable description of the content type.
 686  *
 687  * Returns: a short description of the content type @type.
 688  **/
 689 char *
 690 g_content_type_get_description (const char *type)
 691 {
 692   static GHashTable *type_comment_cache = NULL;
 693   char *comment;
 694
 695   g_return_val_if_fail (type != NULL, NULL);
 696
 697   G_LOCK (gio_xdgmime);
 698   type = xdg_mime_unalias_mime_type (type);
 699
 700   if (type_comment_cache == NULL)
 701     type_comment_cache = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
 702
 703   comment = g_hash_table_lookup (type_comment_cache, type);
 704   comment = g_strdup (comment);
 705   G_UNLOCK (gio_xdgmime);
 706
 707   if (comment != NULL)
 708     return comment;
 709
 710   comment = load_comment_for_mime (type);
 711
 712   G_LOCK (gio_xdgmime);
 713   g_hash_table_insert (type_comment_cache,
 714                        g_strdup (type),
 715                        g_strdup (comment));
 716   G_UNLOCK (gio_xdgmime);
 717
 718   return comment;
 719 }
 720
 721 /**
 722  * g_content_type_get_mime_type:
 723  * @type: a content type string.
 724  *
 725  * Gets the mime-type for the content type. If one is registered
 726  *
 727  * Returns: the registered mime-type for the given @type, or NULL if unknown.
 728  **/
 729 char *
 730 g_content_type_get_mime_type (const char *type)
 731 {
 732   g_return_val_if_fail (type != NULL, NULL);
 733
 734   return g_strdup (type);
 735 }
 736
 737 /**
 738  * g_content_type_get_icon:
 739  * @type: a content type string.
 740  *
 741  * Gets the icon for a content type.
 742  *
 743  * Returns: #GIcon corresponding to the content type.
 744  **/
 745 GIcon *
 746 g_content_type_get_icon (const char *type)
 747 {
 748   char *mimetype_icon, *generic_mimetype_icon, *q;
 749   char *xdg_mimetype_icon, *legacy_mimetype_icon;
 750   char *icon_names[4];
 751   int n = 0;
 752   const char *p;
 753   GIcon *themed_icon;
 754
 755   g_return_val_if_fail (type != NULL, NULL);
 756
 757   G_LOCK (gio_xdgmime);
 758   xdg_mimetype_icon = g_strdup (xdg_mime_get_icon (type));
 759   G_UNLOCK (gio_xdgmime);
 760
 761   mimetype_icon = g_strdup (type);
 762
 763   while ((q = strchr (mimetype_icon, '/')) != NULL)
 764     *q = '-';
 765
 766   p = strchr (type, '/');
 767   if (p == NULL)
 768     p = type + strlen (type);
 769
 770   /* Not all icons have migrated to the new icon theme spec, look for old names too */
 771   legacy_mimetype_icon = g_strconcat ("gnome-mime-", mimetype_icon, NULL);
 772
 773   generic_mimetype_icon = g_malloc (p - type + strlen ("-x-generic") + 1);
 774   memcpy (generic_mimetype_icon, type, p - type);
 775   memcpy (generic_mimetype_icon + (p - type), "-x-generic", strlen ("-x-generic"));
 776   generic_mimetype_icon[(p - type) + strlen ("-x-generic")] = 0;
 777
 778   if (xdg_mimetype_icon)
 779     icon_names[n++] = xdg_mimetype_icon;
 780
 781   icon_names[n++] = mimetype_icon;
 782   icon_names[n++] = legacy_mimetype_icon;
 783   icon_names[n++] = generic_mimetype_icon;
 784
 785   themed_icon = g_themed_icon_new_from_names (icon_names, n);
 786
 787   g_free (xdg_mimetype_icon);
 788   g_free (mimetype_icon);
 789   g_free (legacy_mimetype_icon);
 790   g_free (generic_mimetype_icon);
 791
 792   return themed_icon;
 793 }
 794
 795 /**
 796  * g_content_type_can_be_executable:
 797  * @type: a content type string.
 798  *
 799  * Checks if a content type can be executable. Note that for instance
 800  * things like text files can be executables (i.e. scripts and batch files).
 801  *
 802  * Returns: %TRUE if the file type corresponds to a type that
 803  * can be executable, %FALSE otherwise.
 804  **/
 805 gboolean
 806 g_content_type_can_be_executable (const char *type)
 807 {
 808   g_return_val_if_fail (type != NULL, FALSE);
 809
 810   if (g_content_type_is_a (type, "application/x-executable")  ||
 811       g_content_type_is_a (type, "text/plain"))
 812     return TRUE;
 813
 814   return FALSE;
 815 }
 816
 817 static gboolean
 818 looks_like_text (const guchar *data, gsize data_size)
 819 {
 820   gsize i;
 821   char c;
 822
 823   for (i = 0; i < data_size; i++)
 824     {
 825       c = data[i];
 826
 827       if (g_ascii_iscntrl (c) &&
 828           !g_ascii_isspace (c))
 829         return FALSE;
 830     }
 831   return TRUE;
 832 }
 833
 834 /**
 835  * g_content_type_from_mime_type:
 836  * @mime_type: a mime type string.
 837  *
 838  * Tries to find a content type based on the mime type name.
 839  *
 840  * Returns: Newly allocated string with content type or NULL when does not know.
 841  *
 842  * Since: 2.18
 843  **/
 844 char *
 845 g_content_type_from_mime_type (const char *mime_type)
 846 {
 847   char *umime;
 848
 849   g_return_val_if_fail (mime_type != NULL, NULL);
 850
 851   G_LOCK (gio_xdgmime);
 852   /* mime type and content type are same on unixes */
 853   umime = g_strdup (xdg_mime_unalias_mime_type (mime_type));
 854   G_UNLOCK (gio_xdgmime);
 855
 856   return umime;
 857 }
 858
 859 /**
 860  * g_content_type_guess:
 861  * @filename: a string, or %NULL
 862  * @data: a stream of data, or %NULL
 863  * @data_size: the size of @data
 864  * @result_uncertain: a flag indicating the certainty of the result
 865  *
 866  * Guesses the content type based on example data. If the function is
 867  * uncertain, @result_uncertain will be set to %TRUE. Either @filename
 868  * or @data may be %NULL, in which case the guess will be based solely
 869  * on the other argument.
 870  *
 871  * Returns: a string indicating a guessed content type for the
 872  * given data.
 873  **/
 874 char *
 875 g_content_type_guess (const char   *filename,
 876                       const guchar *data,
 877                       gsize         data_size,
 878                       gboolean     *result_uncertain)
 879 {
 880   char *basename;
 881   const char *name_mimetypes[10], *sniffed_mimetype;
 882   char *mimetype;
 883   int i;
 884   int n_name_mimetypes;
 885   int sniffed_prio;
 886
 887   sniffed_prio = 0;
 888   n_name_mimetypes = 0;
 889   sniffed_mimetype = XDG_MIME_TYPE_UNKNOWN;
 890
 891   if (result_uncertain)
 892     *result_uncertain = FALSE;
 893
 894   G_LOCK (gio_xdgmime);
 895
 896   if (filename)
 897     {
 898       basename = g_path_get_basename (filename);
 899       n_name_mimetypes = xdg_mime_get_mime_types_from_file_name (basename, name_mimetypes, 10);
 900       g_free (basename);
 901     }
 902
 903   /* Got an extension match, and no conflicts. This is it. */
 904   if (n_name_mimetypes == 1)
 905     {
 906       G_UNLOCK (gio_xdgmime);
 907       return g_strdup (name_mimetypes[0]);
 908     }
 909
 910   if (data)
 911     {
 912       sniffed_mimetype = xdg_mime_get_mime_type_for_data (data, data_size, &sniffed_prio);
 913       if (sniffed_mimetype == XDG_MIME_TYPE_UNKNOWN &&
 914           data &&
 915           looks_like_text (data, data_size))
 916         sniffed_mimetype = "text/plain";
 917     }
 918
 919   if (n_name_mimetypes == 0)
 920     {
 921       if (sniffed_mimetype == XDG_MIME_TYPE_UNKNOWN &&
 922           result_uncertain)
 923         *result_uncertain = TRUE;
 924
 925       mimetype = g_strdup (sniffed_mimetype);
 926     }
 927   else
 928     {
 929       mimetype = NULL;
 930       if (sniffed_mimetype != XDG_MIME_TYPE_UNKNOWN)
 931         {
 932           if (sniffed_prio >= 80) /* High priority sniffing match, use that */
 933             mimetype = g_strdup (sniffed_mimetype);
 934           else
 935             {
 936               /* There are conflicts between the name matches and we have a sniffed
 937                  type, use that as a tie breaker. */
 938
 939               for (i = 0; i < n_name_mimetypes; i++)
 940                 {
 941                   if ( xdg_mime_mime_type_subclass (name_mimetypes[i], sniffed_mimetype))
 942                     {
 943                       /* This nametype match is derived from (or the same as) the sniffed type).
 944                          This is probably it. */
 945                       mimetype = g_strdup (name_mimetypes[i]);
 946                       break;
 947                     }
 948                 }
 949             }
 950         }
 951
 952       if (mimetype == NULL)
 953         {
 954           /* Conflicts, and sniffed type was no help or not there. Guess on the first one */
 955           mimetype = g_strdup (name_mimetypes[0]);
 956           if (result_uncertain)
 957             *result_uncertain = TRUE;
 958         }
 959     }
 960
 961   G_UNLOCK (gio_xdgmime);
 962
 963   return mimetype;
 964 }
 965
 966 static void
 967 enumerate_mimetypes_subdir (const char *dir,
 968                             const char *prefix,
 969                             GHashTable *mimetypes)
 970 {
 971   DIR *d;
 972   struct dirent *ent;
 973   char *mimetype;
 974
 975   d = opendir (dir);
 976   if (d)
 977     {
 978       while ((ent = readdir (d)) != NULL)
 979         {
 980           if (g_str_has_suffix (ent->d_name, ".xml"))
 981             {
 982               mimetype = g_strdup_printf ("%s/%.*s", prefix, (int) strlen (ent->d_name) - 4, ent->d_name);
 983               g_hash_table_insert (mimetypes, mimetype, NULL);
 984             }
 985         }
 986       closedir (d);
 987     }
 988 }
 989
 990 static void
 991 enumerate_mimetypes_dir (const char *dir,
 992                          GHashTable *mimetypes)
 993 {
 994   DIR *d;
 995   struct dirent *ent;
 996   char *mimedir;
 997   char *name;
 998
 999   mimedir = g_build_filename (dir, "mime", NULL);
1000
1001   d = opendir (mimedir);
1002   if (d)
1003     {
1004       while ((ent = readdir (d)) != NULL)
1005         {
1006           if (strcmp (ent->d_name, "packages") != 0)
1007             {
1008               name = g_build_filename (mimedir, ent->d_name, NULL);
1009               if (g_file_test (name, G_FILE_TEST_IS_DIR))
1010                 enumerate_mimetypes_subdir (name, ent->d_name, mimetypes);
1011               g_free (name);
1012             }
1013         }
1014       closedir (d);
1015     }
1016
1017   g_free (mimedir);
1018 }
1019
1020 /**
1021  * g_content_types_get_registered:
1022  *
1023  * Gets a list of strings containing all the registered content types
1024  * known to the system. The list and its data should be freed using
1025  * @g_list_foreach(list, g_free, NULL) and @g_list_free(list)
1026  * Returns: #GList of the registered content types.
1027  **/
1028 GList *
1029 g_content_types_get_registered (void)
1030 {
1031   const char * const* dirs;
1032   GHashTable *mimetypes;
1033   GHashTableIter iter;
1034   gpointer key;
1035   int i;
1036   GList *l;
1037
1038   mimetypes = g_hash_table_new (g_str_hash, g_str_equal);
1039
1040   enumerate_mimetypes_dir (g_get_user_data_dir (), mimetypes);
1041   dirs = g_get_system_data_dirs ();
1042
1043   for (i = 0; dirs[i] != NULL; i++)
1044     enumerate_mimetypes_dir (dirs[i], mimetypes);
1045
1046   l = NULL;
1047   g_hash_table_iter_init (&iter, mimetypes);
1048   while (g_hash_table_iter_next (&iter, &key, NULL))
1049     l = g_list_prepend (l, key);
1050
1051   g_hash_table_destroy (mimetypes);
1052
1053   return l;
1054 }
1055
1056
1057 /* tree magic data */
1058 static GList *tree_matches = NULL;
1059 static gboolean need_reload = FALSE;
1060
1061 G_LOCK_DEFINE_STATIC (gio_treemagic);
1062
1063 typedef struct
1064 {
1065   gchar *path;
1066   GFileType type;
1067   guint match_case : 1;
1068   guint executable : 1;
1069   guint non_empty  : 1;
1070   guint on_disc    : 1;
1071   gchar *mimetype;
1072   GList *matches;
1073 } TreeMatchlet;
1074
1075 typedef struct
1076 {
1077   gchar *contenttype;
1078   gint priority;
1079   GList *matches;
1080 } TreeMatch;
1081
1082
1083 static void
1084 tree_matchlet_free (TreeMatchlet *matchlet)
1085 {
1086   g_list_foreach (matchlet->matches, (GFunc)tree_matchlet_free, NULL);
1087   g_list_free (matchlet->matches);
1088   g_free (matchlet->path);
1089   g_free (matchlet->mimetype);
1090   g_slice_free (TreeMatchlet, matchlet);
1091 }
1092
1093 static void
1094 tree_match_free (TreeMatch *match)
1095 {
1096   g_list_foreach (match->matches, (GFunc)tree_matchlet_free, NULL);
1097   g_list_free (match->matches);
1098   g_free (match->contenttype);
1099   g_slice_free (TreeMatch, match);
1100 }
1101
1102 static TreeMatch *
1103 parse_header (gchar *line)
1104 {
1105   gint len;
1106   gchar *s;
1107   TreeMatch *match;
1108
1109   len = strlen (line);
1110
1111   if (line[0] != '[' || line[len - 1] != ']')
1112     return NULL;
1113
1114   line[len - 1] = 0;
1115   s = strchr (line, ':');
1116
1117   match = g_slice_new0 (TreeMatch);
1118   match->priority = atoi (line + 1);
1119   match->contenttype = g_strdup (s + 1);
1120
1121   return match;
1122 }
1123
1124 static TreeMatchlet *
1125 parse_match_line (gchar *line,
1126                   gint  *depth)
1127 {
1128   gchar *s, *p;
1129   TreeMatchlet *matchlet;
1130   gchar **parts;
1131   gint i;
1132
1133   matchlet = g_slice_new0 (TreeMatchlet);
1134
1135   if (line[0] == '>')
1136     {
1137       *depth = 0;
1138       s = line;
1139     }
1140   else
1141     {
1142       *depth = atoi (line);
1143       s = strchr (line, '>');
1144     }
1145   s += 2;
1146   p = strchr (s, '"');
1147   *p = 0;
1148
1149   matchlet->path = g_strdup (s);
1150   s = p + 1;
1151   parts = g_strsplit (s, ",", 0);
1152   if (strcmp (parts[0], "=file") == 0)
1153     matchlet->type = G_FILE_TYPE_REGULAR;
1154   else if (strcmp (parts[0], "=directory") == 0)
1155     matchlet->type = G_FILE_TYPE_DIRECTORY;
1156   else if (strcmp (parts[0], "=link") == 0)
1157     matchlet->type = G_FILE_TYPE_SYMBOLIC_LINK;
1158   else
1159     matchlet->type = G_FILE_TYPE_UNKNOWN;
1160   for (i = 1; parts[i]; i++)
1161     {
1162       if (strcmp (parts[i], "executable") == 0)
1163         matchlet->executable = 1;
1164       else if (strcmp (parts[i], "match-case") == 0)
1165         matchlet->match_case = 1;
1166       else if (strcmp (parts[i], "non-empty") == 0)
1167         matchlet->non_empty = 1;
1168       else if (strcmp (parts[i], "on-disc") == 0)
1169         matchlet->on_disc = 1;
1170       else
1171         matchlet->mimetype = g_strdup (parts[i]);
1172     }
1173
1174   g_strfreev (parts);
1175
1176   return matchlet;
1177 }
1178
1179 static gint
1180 cmp_match (gconstpointer a, gconstpointer b)
1181 {
1182   const TreeMatch *aa = (const TreeMatch *)a;
1183   const TreeMatch *bb = (const TreeMatch *)b;
1184
1185   return bb->priority - aa->priority;
1186 }
1187
1188 static void
1189 insert_match (TreeMatch *match)
1190 {
1191   tree_matches = g_list_insert_sorted (tree_matches, match, cmp_match);
1192 }
1193
1194 static void
1195 insert_matchlet (TreeMatch    *match,
1196                  TreeMatchlet *matchlet,
1197                  gint          depth)
1198 {
1199   if (depth == 0)
1200     match->matches = g_list_append (match->matches, matchlet);
1201   else
1202     {
1203       GList *last;
1204       TreeMatchlet *m;
1205
1206       last = g_list_last (match->matches);
1207       if (!last)
1208         {
1209           tree_matchlet_free (matchlet);
1210           g_warning ("can't insert tree matchlet at depth %d", depth);
1211           return;
1212         }
1213
1214       m = (TreeMatchlet *) last->data;
1215       while (--depth > 0)
1216         {
1217           last = g_list_last (m->matches);
1218           if (!last)
1219             {
1220               tree_matchlet_free (matchlet);
1221               g_warning ("can't insert tree matchlet at depth %d", depth);
1222               return;
1223             }
1224
1225           m = (TreeMatchlet *) last->data;
1226         }
1227       m->matches = g_list_append (m->matches, matchlet);
1228     }
1229 }
1230
1231 static void
1232 read_tree_magic_from_directory (const gchar *prefix)
1233 {
1234   gchar *filename;
1235   gchar *text;
1236   gsize len;
1237   gchar **lines;
1238   gint i;
1239   TreeMatch *match;
1240   TreeMatchlet *matchlet;
1241   gint depth;
1242
1243   filename = g_build_filename (prefix, "mime", "treemagic", NULL);
1244
1245   if (g_file_get_contents (filename, &text, &len, NULL))
1246     {
1247       if (strcmp (text, "MIME-TreeMagic") == 0)
1248         {
1249           lines = g_strsplit (text + strlen ("MIME-TreeMagic") + 2, "\n", 0);
1250           match = NULL;
1251           for (i = 0; lines[i] && lines[i][0]; i++)
1252             {
1253               if (lines[i][0] == '[')
1254                 {
1255                   match = parse_header (lines[i]);
1256                   insert_match (match);
1257                 }
1258               else
1259                 {
1260                   matchlet = parse_match_line (lines[i], &depth);
1261                   insert_matchlet (match, matchlet, depth);
1262                 }
1263             }
1264
1265           g_strfreev (lines);
1266         }
1267       else
1268         g_warning ("%s: header not found, skipping\n", filename);
1269
1270       g_free (text);
1271     }
1272
1273   g_free (filename);
1274 }
1275
1276
1277 static void
1278 xdg_mime_reload (void *user_data)
1279 {
1280   need_reload = TRUE;
1281 }
1282
1283 static void
1284 tree_magic_shutdown (void)
1285 {
1286   g_list_foreach (tree_matches, (GFunc)tree_match_free, NULL);
1287   g_list_free (tree_matches);
1288   tree_matches = NULL;
1289 }
1290
1291 static void
1292 tree_magic_init (void)
1293 {
1294   static gboolean initialized = FALSE;
1295   const gchar *dir;
1296   const gchar * const * dirs;
1297   int i;
1298
1299   if (!initialized)
1300     {
1301       initialized = TRUE;
1302
1303       xdg_mime_register_reload_callback (xdg_mime_reload, NULL, NULL);
1304       need_reload = TRUE;
1305     }
1306
1307   if (need_reload)
1308     {
1309       need_reload = FALSE;
1310
1311       tree_magic_shutdown ();
1312
1313       dir = g_get_user_data_dir ();
1314       read_tree_magic_from_directory (dir);
1315       dirs = g_get_system_data_dirs ();
1316       for (i = 0; dirs[i]; i++)
1317         read_tree_magic_from_directory (dirs[i]);
1318     }
1319 }
1320
1321 /* a filtering enumerator */
1322
1323 typedef struct
1324 {
1325   gchar *path;
1326   gint depth;
1327   gboolean ignore_case;
1328   gchar **components;
1329   gchar **case_components;
1330   GFileEnumerator **enumerators;
1331   GFile **children;
1332 } Enumerator;
1333
1334 static gboolean
1335 component_match (Enumerator  *e,
1336                  gint         depth,
1337                  const gchar *name)
1338 {
1339   gchar *case_folded, *key;
1340   gboolean found;
1341
1342   if (strcmp (name, e->components[depth]) == 0)
1343     return TRUE;
1344
1345   if (!e->ignore_case)
1346     return FALSE;
1347
1348   case_folded = g_utf8_casefold (name, -1);
1349   key = g_utf8_collate_key (case_folded, -1);
1350
1351   found = strcmp (key, e->case_components[depth]) == 0;
1352
1353   g_free (case_folded);
1354   g_free (key);
1355
1356   return found;
1357 }
1358
1359 static GFile *
1360 next_match_recurse (Enumerator *e,
1361                     gint        depth)
1362 {
1363   GFile *file;
1364   GFileInfo *info;
1365   const gchar *name;
1366
1367   while (TRUE)
1368     {
1369       if (e->enumerators[depth] == NULL)
1370         {
1371           if (depth > 0)
1372             {
1373               file = next_match_recurse (e, depth - 1);
1374               if (file)
1375                 {
1376                   e->children[depth] = file;
1377                   e->enumerators[depth] = g_file_enumerate_children (file,
1378                                                                      G_FILE_ATTRIBUTE_STANDARD_NAME,
1379                                                                      G_FILE_QUERY_INFO_NONE,
1380                                                                      NULL,
1381                                                                      NULL);
1382                 }
1383             }
1384           if (e->enumerators[depth] == NULL)
1385             return NULL;
1386         }
1387
1388       while ((info = g_file_enumerator_next_file (e->enumerators[depth], NULL, NULL)))
1389         {
1390           name = g_file_info_get_name (info);
1391           if (component_match (e, depth, name))
1392             {
1393               file = g_file_get_child (e->children[depth], name);
1394               g_object_unref (info);
1395               return file;
1396             }
1397           g_object_unref (info);
1398         }
1399
1400       g_object_unref (e->enumerators[depth]);
1401       e->enumerators[depth] = NULL;
1402       g_object_unref (e->children[depth]);
1403       e->children[depth] = NULL;
1404     }
1405 }
1406
1407 static GFile *
1408 enumerator_next (Enumerator *e)
1409 {
1410   return next_match_recurse (e, e->depth - 1);
1411 }
1412
1413 static Enumerator *
1414 enumerator_new (GFile      *root,
1415                 const char *path,
1416                 gboolean    ignore_case)
1417 {
1418   Enumerator *e;
1419   gint i;
1420   gchar *case_folded;
1421
1422   e = g_new0 (Enumerator, 1);
1423   e->path = g_strdup (path);
1424   e->ignore_case = ignore_case;
1425
1426   e->components = g_strsplit (e->path, G_DIR_SEPARATOR_S, -1);
1427   e->depth = g_strv_length (e->components);
1428   if (e->ignore_case)
1429     {
1430       e->case_components = g_new0 (char *, e->depth + 1);
1431       for (i = 0; e->components[i]; i++)
1432         {
1433           case_folded = g_utf8_casefold (e->components[i], -1);
1434           e->case_components[i] = g_utf8_collate_key (case_folded, -1);
1435           g_free (case_folded);
1436         }
1437     }
1438
1439   e->children = g_new0 (GFile *, e->depth);
1440   e->children[0] = g_object_ref (root);
1441   e->enumerators = g_new0 (GFileEnumerator *, e->depth);
1442   e->enumerators[0] = g_file_enumerate_children (root,
1443                                                  G_FILE_ATTRIBUTE_STANDARD_NAME,
1444                                                  G_FILE_QUERY_INFO_NONE,
1445                                                  NULL,
1446                                                  NULL);
1447
1448   return e;
1449 }
1450
1451 static void
1452 enumerator_free (Enumerator *e)
1453 {
1454   gint i;
1455
1456   for (i = 0; i < e->depth; i++)
1457     {
1458       if (e->enumerators[i])
1459         g_object_unref (e->enumerators[i]);
1460       if (e->children[i])
1461         g_object_unref (e->children[i]);
1462     }
1463
1464   g_free (e->enumerators);
1465   g_free (e->children);
1466   g_strfreev (e->components);
1467   if (e->case_components)
1468     g_strfreev (e->case_components);
1469   g_free (e->path);
1470   g_free (e);
1471 }
1472
1473 static gboolean
1474 matchlet_match (TreeMatchlet *matchlet,
1475                 GFile        *root)
1476 {
1477   GFile *file;
1478   GFileInfo *info;
1479   gboolean result;
1480   const gchar *attrs;
1481   Enumerator *e;
1482   GList *l;
1483
1484   e = enumerator_new (root, matchlet->path, !matchlet->match_case);
1485
1486   do
1487     {
1488       file = enumerator_next (e);
1489       if (!file)
1490         {
1491           enumerator_free (e);
1492           return FALSE;
1493         }
1494
1495       if (matchlet->mimetype)
1496         attrs = G_FILE_ATTRIBUTE_STANDARD_TYPE ","
1497                 G_FILE_ATTRIBUTE_ACCESS_CAN_EXECUTE ","
1498                 G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE;
1499       else
1500         attrs = G_FILE_ATTRIBUTE_STANDARD_TYPE ","
1501                 G_FILE_ATTRIBUTE_ACCESS_CAN_EXECUTE;
1502       info = g_file_query_info (file,
1503                                 attrs,
1504                                 G_FILE_QUERY_INFO_NONE,
1505                                 NULL,
1506                                 NULL);
1507       if (info)
1508         {
1509           result = TRUE;
1510
1511           if (matchlet->type != G_FILE_TYPE_UNKNOWN &&
1512               g_file_info_get_file_type (info) != matchlet->type)
1513             result = FALSE;
1514
1515           if (matchlet->executable &&
1516               !g_file_info_get_attribute_boolean (info, G_FILE_ATTRIBUTE_ACCESS_CAN_EXECUTE))
1517             result = FALSE;
1518         }
1519       else
1520         result = FALSE;
1521
1522       if (result && matchlet->non_empty)
1523         {
1524           GFileEnumerator *child_enum;
1525           GFileInfo *child_info;
1526
1527           child_enum = g_file_enumerate_children (file,
1528                                                   G_FILE_ATTRIBUTE_STANDARD_NAME,
1529                                                   G_FILE_QUERY_INFO_NONE,
1530                                                   NULL,
1531                                                   NULL);
1532
1533           if (child_enum)
1534             {
1535               child_info = g_file_enumerator_next_file (child_enum, NULL, NULL);
1536               if (child_info)
1537                 g_object_unref (child_info);
1538               else
1539                 result = FALSE;
1540               g_object_unref (child_enum);
1541             }
1542           else
1543             result = FALSE;
1544         }
1545
1546       if (result && matchlet->mimetype)
1547         {
1548           if (strcmp (matchlet->mimetype, g_file_info_get_content_type (info)) != 0)
1549             result = FALSE;
1550         }
1551
1552       g_object_unref (info);
1553       g_object_unref (file);
1554     }
1555   while (!result);
1556
1557   enumerator_free (e);
1558
1559   if (!matchlet->matches)
1560     return TRUE;
1561
1562   for (l = matchlet->matches; l; l = l->next)
1563     {
1564       TreeMatchlet *submatchlet;
1565
1566       submatchlet = l->data;
1567       if (matchlet_match (submatchlet, root))
1568         return TRUE;
1569     }
1570
1571   return FALSE;
1572 }
1573
1574 static void
1575 match_match (TreeMatch    *match,
1576              GFile        *root,
1577              GPtrArray    *types)
1578 {
1579   GList *l;
1580
1581   for (l = match->matches; l; l = l->next)
1582     {
1583       TreeMatchlet *matchlet = l->data;
1584       if (matchlet_match (matchlet, root))
1585         {
1586           g_ptr_array_add (types, g_strdup (match->contenttype));
1587           break;
1588         }
1589     }
1590 }
1591
1592 /**
1593  * g_content_type_guess_for_tree:
1594  * @root: the root of the tree to guess a type for
1595  *
1596  * Tries to guess the type of the tree with root @root, by
1597  * looking at the files it contains. The result is an array
1598  * of content types, with the best guess coming first.
1599  *
1600  * The types returned all have the form x-content/foo, e.g.
1601  * x-content/audio-cdda (for audio CDs) or x-content/image-dcf
1602  * (for a camera memory card). See the <ulink url="http://www.freedesktop.org/wiki/Specifications/shared-mime-info-spec">shared-mime-info</ulink>
1603  * specification for more on x-content types.
1604  *
1605  * This function is useful in the implementation of g_mount_guess_content_type().
1606  *
1607  * Returns: an %NULL-terminated array of zero or more content types, or %NULL.
1608  *    Free with g_strfreev()
1609  *
1610  * Since: 2.18
1611  */
1612 char **
1613 g_content_type_guess_for_tree (GFile *root)
1614 {
1615   GPtrArray *types;
1616   GList *l;
1617
1618   types = g_ptr_array_new ();
1619
1620   G_LOCK (gio_treemagic);
1621
1622   tree_magic_init ();
1623   for (l = tree_matches; l; l = l->next)
1624     {
1625       TreeMatch *match = l->data;
1626       match_match (match, root, types);
1627     }
1628
1629   G_UNLOCK (gio_treemagic);
1630
1631   g_ptr_array_add (types, NULL);
1632
1633   return (char **)g_ptr_array_free (types, FALSE);
1634 }
1635
1636 #endif /* Unix version */
1637
1638 #define __G_CONTENT_TYPE_C__
1639 #include "gioaliasdef.c"