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
  39 /**
  40  * SECTION:gcontenttype
  41  * @short_description: Platform-specific content typing
  42  * @include: gio/gio.h
  43  *
  44  * A content type is a platform specific string that defines the type
  45  * of a file. On UNIX it is a <ulink url="http://www.wikipedia.org/wiki/Internet_media_type">mime type</ulink> like "text/plain" or "image/png".
  46  * On Win32 it is an extension string like ".doc", ".txt" or a perceived
  47  * string like "audio". Such strings can be looked up in the registry at
  48  * 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 gchar *type1,
 108                        const gchar *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 gchar *type,
 133                      const gchar *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 gchar *type)
 155 {
 156   g_return_val_if_fail (type != NULL, FALSE);
 157
 158   return strcmp ("*", type) == 0;
 159 }
 160
 161 gchar *
 162 g_content_type_get_description (const gchar *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 gchar *
 185 g_content_type_get_mime_type (const gchar *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 gchar *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 gchar *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) && c != '\b')
 299         return FALSE;
 300     }
 301   return TRUE;
 302 }
 303
 304 gchar *
 305 g_content_type_from_mime_type (const gchar *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 gchar *
 319 g_content_type_guess (const gchar  *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 (result_uncertain)
 331     *result_uncertain = FALSE;
 332
 333   if (filename)
 334     {
 335       basename = g_path_get_basename (filename);
 336       dot = strrchr (basename, '.');
 337       if (dot)
 338         type = g_strdup (dot);
 339       g_free (basename);
 340     }
 341
 342   if (type)
 343     return type;
 344
 345   if (data && looks_like_text (data, data_size))
 346     return g_strdup (".txt");
 347
 348   return g_strdup ("*");
 349 }
 350
 351 GList *
 352 g_content_types_get_registered (void)
 353 {
 354   DWORD index;
 355   wchar_t keyname[256];
 356   DWORD key_len;
 357   char *key_utf8;
 358   GList *types;
 359
 360   types = NULL;
 361   index = 0;
 362   key_len = 256;
 363   while (RegEnumKeyExW(HKEY_CLASSES_ROOT,
 364                        index,
 365                        keyname,
 366                        &key_len,
 367                        NULL,
 368                        NULL,
 369                        NULL,
 370                        NULL) == ERROR_SUCCESS)
 371     {
 372       key_utf8 = g_utf16_to_utf8 (keyname, -1, NULL, NULL, NULL);
 373       if (key_utf8)
 374         {
 375           if (*key_utf8 == '.')
 376             types = g_list_prepend (types, key_utf8);
 377           else
 378             g_free (key_utf8);
 379         }
 380       index++;
 381       key_len = 256;
 382     }
 383
 384   return g_list_reverse (types);
 385 }
 386
 387 gchar **
 388 g_content_type_guess_for_tree (GFile *root)
 389 {
 390   /* FIXME: implement */
 391   return NULL;
 392 }
 393
 394 #else /* !G_OS_WIN32 - Unix specific version */
 395
 396 #include <dirent.h>
 397
 398 #define XDG_PREFIX _gio_xdg
 399 #include "xdgmime/xdgmime.h"
 400
 401 /* We lock this mutex whenever we modify global state in this module.  */
 402 G_LOCK_DEFINE_STATIC (gio_xdgmime);
 403
 404 gsize
 405 _g_unix_content_type_get_sniff_len (void)
 406 {
 407   gsize size;
 408
 409   G_LOCK (gio_xdgmime);
 410   size = xdg_mime_get_max_buffer_extents ();
 411   G_UNLOCK (gio_xdgmime);
 412
 413   return size;
 414 }
 415
 416 gchar *
 417 _g_unix_content_type_unalias (const gchar *type)
 418 {
 419   gchar *res;
 420
 421   G_LOCK (gio_xdgmime);
 422   res = g_strdup (xdg_mime_unalias_mime_type (type));
 423   G_UNLOCK (gio_xdgmime);
 424
 425   return res;
 426 }
 427
 428 gchar **
 429 _g_unix_content_type_get_parents (const gchar *type)
 430 {
 431   const gchar *umime;
 432   gchar **parents;
 433   GPtrArray *array;
 434   int i;
 435
 436   array = g_ptr_array_new ();
 437
 438   G_LOCK (gio_xdgmime);
 439
 440   umime = xdg_mime_unalias_mime_type (type);
 441
 442   g_ptr_array_add (array, g_strdup (umime));
 443
 444   parents = xdg_mime_list_mime_parents (umime);
 445   for (i = 0; parents && parents[i] != NULL; i++)
 446     g_ptr_array_add (array, g_strdup (parents[i]));
 447
 448   free (parents);
 449
 450   G_UNLOCK (gio_xdgmime);
 451
 452   g_ptr_array_add (array, NULL);
 453
 454   return (gchar **)g_ptr_array_free (array, FALSE);
 455 }
 456
 457 /**
 458  * g_content_type_equals:
 459  * @type1: a content type string
 460  * @type2: a content type string
 461  *
 462  * Compares two content types for equality.
 463  *
 464  * Returns: %TRUE if the two strings are identical or equivalent,
 465  *     %FALSE otherwise.
 466  */
 467 gboolean
 468 g_content_type_equals (const gchar *type1,
 469                        const gchar *type2)
 470 {
 471   gboolean res;
 472
 473   g_return_val_if_fail (type1 != NULL, FALSE);
 474   g_return_val_if_fail (type2 != NULL, FALSE);
 475
 476   G_LOCK (gio_xdgmime);
 477   res = xdg_mime_mime_type_equal (type1, type2);
 478   G_UNLOCK (gio_xdgmime);
 479
 480   return res;
 481 }
 482
 483 /**
 484  * g_content_type_is_a:
 485  * @type: a content type string
 486  * @supertype: a content type string
 487  *
 488  * Determines if @type is a subset of @supertype.
 489  *
 490  * Returns: %TRUE if @type is a kind of @supertype,
 491  *     %FALSE otherwise.
 492  */
 493 gboolean
 494 g_content_type_is_a (const gchar *type,
 495                      const gchar *supertype)
 496 {
 497   gboolean res;
 498
 499   g_return_val_if_fail (type != NULL, FALSE);
 500   g_return_val_if_fail (supertype != NULL, FALSE);
 501
 502   G_LOCK (gio_xdgmime);
 503   res = xdg_mime_mime_type_subclass (type, supertype);
 504   G_UNLOCK (gio_xdgmime);
 505
 506   return res;
 507 }
 508
 509 /**
 510  * g_content_type_is_unknown:
 511  * @type: a content type string
 512  *
 513  * Checks if the content type is the generic "unknown" type.
 514  * On UNIX this is the "application/octet-stream" mimetype,
 515  * while on win32 it is "*".
 516  *
 517  * Returns: %TRUE if the type is the unknown type.
 518  */
 519 gboolean
 520 g_content_type_is_unknown (const gchar *type)
 521 {
 522   g_return_val_if_fail (type != NULL, FALSE);
 523
 524   return strcmp (XDG_MIME_TYPE_UNKNOWN, type) == 0;
 525 }
 526
 527
 528 typedef enum {
 529   MIME_TAG_TYPE_OTHER,
 530   MIME_TAG_TYPE_COMMENT
 531 } MimeTagType;
 532
 533 typedef struct {
 534   int current_type;
 535   int current_lang_level;
 536   int comment_lang_level;
 537   char *comment;
 538 } MimeParser;
 539
 540
 541 static int
 542 language_level (const char *lang)
 543 {
 544   const char * const *lang_list;
 545   int i;
 546
 547   /* The returned list is sorted from most desirable to least
 548      desirable and always contains the default locale "C". */
 549   lang_list = g_get_language_names ();
 550
 551   for (i = 0; lang_list[i]; i++)
 552     if (strcmp (lang_list[i], lang) == 0)
 553       return 1000-i;
 554
 555   return 0;
 556 }
 557
 558 static void
 559 mime_info_start_element (GMarkupParseContext  *context,
 560                          const gchar          *element_name,
 561                          const gchar         **attribute_names,
 562                          const gchar         **attribute_values,
 563                          gpointer              user_data,
 564                          GError              **error)
 565 {
 566   int i;
 567   const char *lang;
 568   MimeParser *parser = user_data;
 569
 570   if (strcmp (element_name, "comment") == 0)
 571     {
 572       lang = "C";
 573       for (i = 0; attribute_names[i]; i++)
 574         if (strcmp (attribute_names[i], "xml:lang") == 0)
 575           {
 576             lang = attribute_values[i];
 577             break;
 578           }
 579
 580       parser->current_lang_level = language_level (lang);
 581       parser->current_type = MIME_TAG_TYPE_COMMENT;
 582     }
 583   else
 584     parser->current_type = MIME_TAG_TYPE_OTHER;
 585 }
 586
 587 static void
 588 mime_info_end_element (GMarkupParseContext  *context,
 589                        const gchar          *element_name,
 590                        gpointer              user_data,
 591                        GError              **error)
 592 {
 593   MimeParser *parser = user_data;
 594
 595   parser->current_type = MIME_TAG_TYPE_OTHER;
 596 }
 597
 598 static void
 599 mime_info_text (GMarkupParseContext  *context,
 600                 const gchar          *text,
 601                 gsize                 text_len,
 602                 gpointer              user_data,
 603                 GError              **error)
 604 {
 605   MimeParser *parser = user_data;
 606
 607   if (parser->current_type == MIME_TAG_TYPE_COMMENT &&
 608       parser->current_lang_level > parser->comment_lang_level)
 609     {
 610       g_free (parser->comment);
 611       parser->comment = g_strndup (text, text_len);
 612       parser->comment_lang_level = parser->current_lang_level;
 613     }
 614 }
 615
 616 static char *
 617 load_comment_for_mime_helper (const char *dir,
 618                               const char *basename)
 619 {
 620   GMarkupParseContext *context;
 621   char *filename, *data;
 622   gsize len;
 623   gboolean res;
 624   MimeParser parse_data = {0};
 625   GMarkupParser parser = {
 626     mime_info_start_element,
 627     mime_info_end_element,
 628     mime_info_text
 629   };
 630
 631   filename = g_build_filename (dir, "mime", basename, NULL);
 632
 633   res = g_file_get_contents (filename,  &data,  &len,  NULL);
 634   g_free (filename);
 635   if (!res)
 636     return NULL;
 637
 638   context = g_markup_parse_context_new   (&parser, 0, &parse_data, NULL);
 639   res = g_markup_parse_context_parse (context, data, len, NULL);
 640   g_free (data);
 641   g_markup_parse_context_free (context);
 642
 643   if (!res)
 644     return NULL;
 645
 646   return parse_data.comment;
 647 }
 648
 649
 650 static char *
 651 load_comment_for_mime (const char *mimetype)
 652 {
 653   const char * const* dirs;
 654   char *basename;
 655   char *comment;
 656   int i;
 657
 658   basename = g_strdup_printf ("%s.xml", mimetype);
 659
 660   comment = load_comment_for_mime_helper (g_get_user_data_dir (), basename);
 661   if (comment)
 662     {
 663       g_free (basename);
 664       return comment;
 665     }
 666
 667   dirs = g_get_system_data_dirs ();
 668
 669   for (i = 0; dirs[i] != NULL; i++)
 670     {
 671       comment = load_comment_for_mime_helper (dirs[i], basename);
 672       if (comment)
 673         {
 674           g_free (basename);
 675           return comment;
 676         }
 677     }
 678   g_free (basename);
 679
 680   return g_strdup_printf (_("%s type"), mimetype);
 681 }
 682
 683 /**
 684  * g_content_type_get_description:
 685  * @type: a content type string
 686  *
 687  * Gets the human readable description of the content type.
 688  *
 689  * Returns: a short description of the content type @type. Free the
 690  *     returned string with g_free()
 691  */
 692 gchar *
 693 g_content_type_get_description (const gchar *type)
 694 {
 695   static GHashTable *type_comment_cache = NULL;
 696   gchar *comment;
 697
 698   g_return_val_if_fail (type != NULL, NULL);
 699
 700   G_LOCK (gio_xdgmime);
 701   type = xdg_mime_unalias_mime_type (type);
 702
 703   if (type_comment_cache == NULL)
 704     type_comment_cache = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
 705
 706   comment = g_hash_table_lookup (type_comment_cache, type);
 707   comment = g_strdup (comment);
 708   G_UNLOCK (gio_xdgmime);
 709
 710   if (comment != NULL)
 711     return comment;
 712
 713   comment = load_comment_for_mime (type);
 714
 715   G_LOCK (gio_xdgmime);
 716   g_hash_table_insert (type_comment_cache,
 717                        g_strdup (type),
 718                        g_strdup (comment));
 719   G_UNLOCK (gio_xdgmime);
 720
 721   return comment;
 722 }
 723
 724 /**
 725  * g_content_type_get_mime_type:
 726  * @type: a content type string
 727  *
 728  * Gets the mime type for the content type, if one is registered.
 729  *
 730  * Returns: (allow-none): the registered mime type for the given @type,
 731  *     or %NULL if unknown.
 732  */
 733 char *
 734 g_content_type_get_mime_type (const char *type)
 735 {
 736   g_return_val_if_fail (type != NULL, NULL);
 737
 738   return g_strdup (type);
 739 }
 740
 741 /**
 742  * g_content_type_get_icon:
 743  * @type: a content type string
 744  *
 745  * Gets the icon for a content type.
 746  *
 747  * Returns: (transfer full): #GIcon corresponding to the content type. Free the returned
 748  *     object with g_object_unref()
 749  */
 750 GIcon *
 751 g_content_type_get_icon (const gchar *type)
 752 {
 753   char *mimetype_icon, *generic_mimetype_icon, *q;
 754   char *xdg_mimetype_icon, *legacy_mimetype_icon;
 755   char *xdg_mimetype_generic_icon;
 756   char *icon_names[5];
 757   int n = 0;
 758   const char *p;
 759   GIcon *themed_icon;
 760
 761   g_return_val_if_fail (type != NULL, NULL);
 762
 763   G_LOCK (gio_xdgmime);
 764   xdg_mimetype_icon = g_strdup (xdg_mime_get_icon (type));
 765   xdg_mimetype_generic_icon = g_strdup (xdg_mime_get_generic_icon (type));
 766   G_UNLOCK (gio_xdgmime);
 767
 768   mimetype_icon = g_strdup (type);
 769
 770   while ((q = strchr (mimetype_icon, '/')) != NULL)
 771     *q = '-';
 772
 773   p = strchr (type, '/');
 774   if (p == NULL)
 775     p = type + strlen (type);
 776
 777   /* Not all icons have migrated to the new icon theme spec, look for old names too */
 778   legacy_mimetype_icon = g_strconcat ("gnome-mime-", mimetype_icon, NULL);
 779
 780   generic_mimetype_icon = g_malloc (p - type + strlen ("-x-generic") + 1);
 781   memcpy (generic_mimetype_icon, type, p - type);
 782   memcpy (generic_mimetype_icon + (p - type), "-x-generic", strlen ("-x-generic"));
 783   generic_mimetype_icon[(p - type) + strlen ("-x-generic")] = 0;
 784
 785   if (xdg_mimetype_icon)
 786     icon_names[n++] = xdg_mimetype_icon;
 787
 788   icon_names[n++] = mimetype_icon;
 789   icon_names[n++] = legacy_mimetype_icon;
 790
 791   if (xdg_mimetype_generic_icon)
 792     icon_names[n++] = xdg_mimetype_generic_icon;
 793
 794   icon_names[n++] = generic_mimetype_icon;
 795
 796   themed_icon = g_themed_icon_new_from_names (icon_names, n);
 797
 798   g_free (xdg_mimetype_icon);
 799   g_free (xdg_mimetype_generic_icon);
 800   g_free (mimetype_icon);
 801   g_free (legacy_mimetype_icon);
 802   g_free (generic_mimetype_icon);
 803
 804   return themed_icon;
 805 }
 806
 807 /**
 808  * g_content_type_can_be_executable:
 809  * @type: a content type string
 810  *
 811  * Checks if a content type can be executable. Note that for instance
 812  * things like text files can be executables (i.e. scripts and batch files).
 813  *
 814  * Returns: %TRUE if the file type corresponds to a type that
 815  *     can be executable, %FALSE otherwise.
 816  */
 817 gboolean
 818 g_content_type_can_be_executable (const gchar *type)
 819 {
 820   g_return_val_if_fail (type != NULL, FALSE);
 821
 822   if (g_content_type_is_a (type, "application/x-executable")  ||
 823       g_content_type_is_a (type, "text/plain"))
 824     return TRUE;
 825
 826   return FALSE;
 827 }
 828
 829 static gboolean
 830 looks_like_text (const guchar *data, gsize data_size)
 831 {
 832   gsize i;
 833   char c;
 834
 835   for (i = 0; i < data_size; i++)
 836     {
 837       c = data[i];
 838
 839       if (g_ascii_iscntrl (c) &&
 840           !g_ascii_isspace (c) &&
 841           c != '\b')
 842         return FALSE;
 843     }
 844   return TRUE;
 845 }
 846
 847 /**
 848  * g_content_type_from_mime_type:
 849  * @mime_type: a mime type string
 850  *
 851  * Tries to find a content type based on the mime type name.
 852  *
 853  * Returns: (allow-none): Newly allocated string with content type
 854  *     or %NULL. Free with g_free()
 855  *
 856  * Since: 2.18
 857  **/
 858 gchar *
 859 g_content_type_from_mime_type (const gchar *mime_type)
 860 {
 861   char *umime;
 862
 863   g_return_val_if_fail (mime_type != NULL, NULL);
 864
 865   G_LOCK (gio_xdgmime);
 866   /* mime type and content type are same on unixes */
 867   umime = g_strdup (xdg_mime_unalias_mime_type (mime_type));
 868   G_UNLOCK (gio_xdgmime);
 869
 870   return umime;
 871 }
 872
 873 /**
 874  * g_content_type_guess:
 875  * @filename: (allow-none): a string, or %NULL
 876  * @data: (allow-none) (array length=data_size): a stream of data, or %NULL
 877  * @data_size: the size of @data
 878  * @result_uncertain: (allow-none) (out): return location for the certainty
 879  *     of the result, or %NULL
 880  *
 881  * Guesses the content type based on example data. If the function is
 882  * uncertain, @result_uncertain will be set to %TRUE. Either @filename
 883  * or @data may be %NULL, in which case the guess will be based solely
 884  * on the other argument.
 885  *
 886  * Returns: a string indicating a guessed content type for the
 887  *     given data. Free with g_free()
 888  */
 889 gchar *
 890 g_content_type_guess (const gchar  *filename,
 891                       const guchar *data,
 892                       gsize         data_size,
 893                       gboolean     *result_uncertain)
 894 {
 895   char *basename;
 896   const char *name_mimetypes[10], *sniffed_mimetype;
 897   char *mimetype;
 898   int i;
 899   int n_name_mimetypes;
 900   int sniffed_prio;
 901
 902   sniffed_prio = 0;
 903   n_name_mimetypes = 0;
 904   sniffed_mimetype = XDG_MIME_TYPE_UNKNOWN;
 905
 906   if (result_uncertain)
 907     *result_uncertain = FALSE;
 908
 909   G_LOCK (gio_xdgmime);
 910
 911   if (filename)
 912     {
 913       i = strlen (filename);
 914       if (filename[i - 1] == '/')
 915         {
 916           name_mimetypes[0] = "inode/directory";
 917           name_mimetypes[1] = NULL;
 918           n_name_mimetypes = 1;
 919           if (result_uncertain)
 920             *result_uncertain = TRUE;
 921         }
 922       else
 923         {
 924           basename = g_path_get_basename (filename);
 925           n_name_mimetypes = xdg_mime_get_mime_types_from_file_name (basename, name_mimetypes, 10);
 926           g_free (basename);
 927         }
 928     }
 929
 930   /* Got an extension match, and no conflicts. This is it. */
 931   if (n_name_mimetypes == 1)
 932     {
 933       G_UNLOCK (gio_xdgmime);
 934       return g_strdup (name_mimetypes[0]);
 935     }
 936
 937   if (data)
 938     {
 939       sniffed_mimetype = xdg_mime_get_mime_type_for_data (data, data_size, &sniffed_prio);
 940       if (sniffed_mimetype == XDG_MIME_TYPE_UNKNOWN &&
 941           data &&
 942           looks_like_text (data, data_size))
 943         sniffed_mimetype = "text/plain";
 944
 945       /* For security reasons we don't ever want to sniff desktop files
 946        * where we know the filename and it doesn't have a .desktop extension.
 947        * This is because desktop files allow executing any application and
 948        * we don't want to make it possible to hide them looking like something
 949        * else.
 950        */
 951       if (filename != NULL &&
 952           strcmp (sniffed_mimetype, "application/x-desktop") == 0)
 953         sniffed_mimetype = "text/plain";
 954     }
 955
 956   if (n_name_mimetypes == 0)
 957     {
 958       if (sniffed_mimetype == XDG_MIME_TYPE_UNKNOWN &&
 959           result_uncertain)
 960         *result_uncertain = TRUE;
 961
 962       mimetype = g_strdup (sniffed_mimetype);
 963     }
 964   else
 965     {
 966       mimetype = NULL;
 967       if (sniffed_mimetype != XDG_MIME_TYPE_UNKNOWN)
 968         {
 969           if (sniffed_prio >= 80) /* High priority sniffing match, use that */
 970             mimetype = g_strdup (sniffed_mimetype);
 971           else
 972             {
 973               /* There are conflicts between the name matches and we
 974                * have a sniffed type, use that as a tie breaker.
 975                */
 976               for (i = 0; i < n_name_mimetypes; i++)
 977                 {
 978                   if ( xdg_mime_mime_type_subclass (name_mimetypes[i], sniffed_mimetype))
 979                     {
 980                       /* This nametype match is derived from (or the same as)
 981                        * the sniffed type). This is probably it.
 982                        */
 983                       mimetype = g_strdup (name_mimetypes[i]);
 984                       break;
 985                     }
 986                 }
 987             }
 988         }
 989
 990       if (mimetype == NULL)
 991         {
 992           /* Conflicts, and sniffed type was no help or not there.
 993            * Guess on the first one
 994            */
 995           mimetype = g_strdup (name_mimetypes[0]);
 996           if (result_uncertain)
 997             *result_uncertain = TRUE;
 998         }
 999     }
1000
1001   G_UNLOCK (gio_xdgmime);
1002
1003   return mimetype;
1004 }
1005
1006 static void
1007 enumerate_mimetypes_subdir (const char *dir,
1008                             const char *prefix,
1009                             GHashTable *mimetypes)
1010 {
1011   DIR *d;
1012   struct dirent *ent;
1013   char *mimetype;
1014
1015   d = opendir (dir);
1016   if (d)
1017     {
1018       while ((ent = readdir (d)) != NULL)
1019         {
1020           if (g_str_has_suffix (ent->d_name, ".xml"))
1021             {
1022               mimetype = g_strdup_printf ("%s/%.*s", prefix, (int) strlen (ent->d_name) - 4, ent->d_name);
1023               g_hash_table_replace (mimetypes, mimetype, NULL);
1024             }
1025         }
1026       closedir (d);
1027     }
1028 }
1029
1030 static void
1031 enumerate_mimetypes_dir (const char *dir,
1032                          GHashTable *mimetypes)
1033 {
1034   DIR *d;
1035   struct dirent *ent;
1036   char *mimedir;
1037   char *name;
1038
1039   mimedir = g_build_filename (dir, "mime", NULL);
1040
1041   d = opendir (mimedir);
1042   if (d)
1043     {
1044       while ((ent = readdir (d)) != NULL)
1045         {
1046           if (strcmp (ent->d_name, "packages") != 0)
1047             {
1048               name = g_build_filename (mimedir, ent->d_name, NULL);
1049               if (g_file_test (name, G_FILE_TEST_IS_DIR))
1050                 enumerate_mimetypes_subdir (name, ent->d_name, mimetypes);
1051               g_free (name);
1052             }
1053         }
1054       closedir (d);
1055     }
1056
1057   g_free (mimedir);
1058 }
1059
1060 /**
1061  * g_content_types_get_registered:
1062  *
1063  * Gets a list of strings containing all the registered content types
1064  * known to the system. The list and its data should be freed using
1065  * <programlisting>
1066  * g_list_foreach (list, g_free, NULL);
1067  * g_list_free (list);
1068  * </programlisting>
1069  *
1070  * Returns: (element-type utf8) (transfer full): #GList of the registered content types
1071  */
1072 GList *
1073 g_content_types_get_registered (void)
1074 {
1075   const char * const* dirs;
1076   GHashTable *mimetypes;
1077   GHashTableIter iter;
1078   gpointer key;
1079   int i;
1080   GList *l;
1081
1082   mimetypes = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
1083
1084   enumerate_mimetypes_dir (g_get_user_data_dir (), mimetypes);
1085   dirs = g_get_system_data_dirs ();
1086
1087   for (i = 0; dirs[i] != NULL; i++)
1088     enumerate_mimetypes_dir (dirs[i], mimetypes);
1089
1090   l = NULL;
1091   g_hash_table_iter_init (&iter, mimetypes);
1092   while (g_hash_table_iter_next (&iter, &key, NULL))
1093     {
1094       l = g_list_prepend (l, key);
1095       g_hash_table_iter_steal (&iter);
1096     }
1097
1098   g_hash_table_destroy (mimetypes);
1099
1100   return l;
1101 }
1102
1103
1104 /* tree magic data */
1105 static GList *tree_matches = NULL;
1106 static gboolean need_reload = FALSE;
1107
1108 G_LOCK_DEFINE_STATIC (gio_treemagic);
1109
1110 typedef struct
1111 {
1112   gchar *path;
1113   GFileType type;
1114   guint match_case : 1;
1115   guint executable : 1;
1116   guint non_empty  : 1;
1117   guint on_disc    : 1;
1118   gchar *mimetype;
1119   GList *matches;
1120 } TreeMatchlet;
1121
1122 typedef struct
1123 {
1124   gchar *contenttype;
1125   gint priority;
1126   GList *matches;
1127 } TreeMatch;
1128
1129
1130 static void
1131 tree_matchlet_free (TreeMatchlet *matchlet)
1132 {
1133   g_list_foreach (matchlet->matches, (GFunc)tree_matchlet_free, NULL);
1134   g_list_free (matchlet->matches);
1135   g_free (matchlet->path);
1136   g_free (matchlet->mimetype);
1137   g_slice_free (TreeMatchlet, matchlet);
1138 }
1139
1140 static void
1141 tree_match_free (TreeMatch *match)
1142 {
1143   g_list_foreach (match->matches, (GFunc)tree_matchlet_free, NULL);
1144   g_list_free (match->matches);
1145   g_free (match->contenttype);
1146   g_slice_free (TreeMatch, match);
1147 }
1148
1149 static TreeMatch *
1150 parse_header (gchar *line)
1151 {
1152   gint len;
1153   gchar *s;
1154   TreeMatch *match;
1155
1156   len = strlen (line);
1157
1158   if (line[0] != '[' || line[len - 1] != ']')
1159     return NULL;
1160
1161   line[len - 1] = 0;
1162   s = strchr (line, ':');
1163
1164   match = g_slice_new0 (TreeMatch);
1165   match->priority = atoi (line + 1);
1166   match->contenttype = g_strdup (s + 1);
1167
1168   return match;
1169 }
1170
1171 static TreeMatchlet *
1172 parse_match_line (gchar *line,
1173                   gint  *depth)
1174 {
1175   gchar *s, *p;
1176   TreeMatchlet *matchlet;
1177   gchar **parts;
1178   gint i;
1179
1180   matchlet = g_slice_new0 (TreeMatchlet);
1181
1182   if (line[0] == '>')
1183     {
1184       *depth = 0;
1185       s = line;
1186     }
1187   else
1188     {
1189       *depth = atoi (line);
1190       s = strchr (line, '>');
1191     }
1192   s += 2;
1193   p = strchr (s, '"');
1194   *p = 0;
1195
1196   matchlet->path = g_strdup (s);
1197   s = p + 1;
1198   parts = g_strsplit (s, ",", 0);
1199   if (strcmp (parts[0], "=file") == 0)
1200     matchlet->type = G_FILE_TYPE_REGULAR;
1201   else if (strcmp (parts[0], "=directory") == 0)
1202     matchlet->type = G_FILE_TYPE_DIRECTORY;
1203   else if (strcmp (parts[0], "=link") == 0)
1204     matchlet->type = G_FILE_TYPE_SYMBOLIC_LINK;
1205   else
1206     matchlet->type = G_FILE_TYPE_UNKNOWN;
1207   for (i = 1; parts[i]; i++)
1208     {
1209       if (strcmp (parts[i], "executable") == 0)
1210         matchlet->executable = 1;
1211       else if (strcmp (parts[i], "match-case") == 0)
1212         matchlet->match_case = 1;
1213       else if (strcmp (parts[i], "non-empty") == 0)
1214         matchlet->non_empty = 1;
1215       else if (strcmp (parts[i], "on-disc") == 0)
1216         matchlet->on_disc = 1;
1217       else
1218         matchlet->mimetype = g_strdup (parts[i]);
1219     }
1220
1221   g_strfreev (parts);
1222
1223   return matchlet;
1224 }
1225
1226 static gint
1227 cmp_match (gconstpointer a, gconstpointer b)
1228 {
1229   const TreeMatch *aa = (const TreeMatch *)a;
1230   const TreeMatch *bb = (const TreeMatch *)b;
1231
1232   return bb->priority - aa->priority;
1233 }
1234
1235 static void
1236 insert_match (TreeMatch *match)
1237 {
1238   tree_matches = g_list_insert_sorted (tree_matches, match, cmp_match);
1239 }
1240
1241 static void
1242 insert_matchlet (TreeMatch    *match,
1243                  TreeMatchlet *matchlet,
1244                  gint          depth)
1245 {
1246   if (depth == 0)
1247     match->matches = g_list_append (match->matches, matchlet);
1248   else
1249     {
1250       GList *last;
1251       TreeMatchlet *m;
1252
1253       last = g_list_last (match->matches);
1254       if (!last)
1255         {
1256           tree_matchlet_free (matchlet);
1257           g_warning ("can't insert tree matchlet at depth %d", depth);
1258           return;
1259         }
1260
1261       m = (TreeMatchlet *) last->data;
1262       while (--depth > 0)
1263         {
1264           last = g_list_last (m->matches);
1265           if (!last)
1266             {
1267               tree_matchlet_free (matchlet);
1268               g_warning ("can't insert tree matchlet at depth %d", depth);
1269               return;
1270             }
1271
1272           m = (TreeMatchlet *) last->data;
1273         }
1274       m->matches = g_list_append (m->matches, matchlet);
1275     }
1276 }
1277
1278 static void
1279 read_tree_magic_from_directory (const gchar *prefix)
1280 {
1281   gchar *filename;
1282   gchar *text;
1283   gsize len;
1284   gchar **lines;
1285   gint i;
1286   TreeMatch *match;
1287   TreeMatchlet *matchlet;
1288   gint depth;
1289
1290   filename = g_build_filename (prefix, "mime", "treemagic", NULL);
1291
1292   if (g_file_get_contents (filename, &text, &len, NULL))
1293     {
1294       if (strcmp (text, "MIME-TreeMagic") == 0)
1295         {
1296           lines = g_strsplit (text + strlen ("MIME-TreeMagic") + 2, "\n", 0);
1297           match = NULL;
1298           for (i = 0; lines[i] && lines[i][0]; i++)
1299             {
1300               if (lines[i][0] == '[')
1301                 {
1302                   match = parse_header (lines[i]);
1303                   insert_match (match);
1304                 }
1305               else
1306                 {
1307                   matchlet = parse_match_line (lines[i], &depth);
1308                   insert_matchlet (match, matchlet, depth);
1309                 }
1310             }
1311
1312           g_strfreev (lines);
1313         }
1314       else
1315         g_warning ("%s: header not found, skipping\n", filename);
1316
1317       g_free (text);
1318     }
1319
1320   g_free (filename);
1321 }
1322
1323
1324 static void
1325 xdg_mime_reload (void *user_data)
1326 {
1327   need_reload = TRUE;
1328 }
1329
1330 static void
1331 tree_magic_shutdown (void)
1332 {
1333   g_list_foreach (tree_matches, (GFunc)tree_match_free, NULL);
1334   g_list_free (tree_matches);
1335   tree_matches = NULL;
1336 }
1337
1338 static void
1339 tree_magic_init (void)
1340 {
1341   static gboolean initialized = FALSE;
1342   const gchar *dir;
1343   const gchar * const * dirs;
1344   int i;
1345
1346   if (!initialized)
1347     {
1348       initialized = TRUE;
1349
1350       xdg_mime_register_reload_callback (xdg_mime_reload, NULL, NULL);
1351       need_reload = TRUE;
1352     }
1353
1354   if (need_reload)
1355     {
1356       need_reload = FALSE;
1357
1358       tree_magic_shutdown ();
1359
1360       dir = g_get_user_data_dir ();
1361       read_tree_magic_from_directory (dir);
1362       dirs = g_get_system_data_dirs ();
1363       for (i = 0; dirs[i]; i++)
1364         read_tree_magic_from_directory (dirs[i]);
1365     }
1366 }
1367
1368 /* a filtering enumerator */
1369
1370 typedef struct
1371 {
1372   gchar *path;
1373   gint depth;
1374   gboolean ignore_case;
1375   gchar **components;
1376   gchar **case_components;
1377   GFileEnumerator **enumerators;
1378   GFile **children;
1379 } Enumerator;
1380
1381 static gboolean
1382 component_match (Enumerator  *e,
1383                  gint         depth,
1384                  const gchar *name)
1385 {
1386   gchar *case_folded, *key;
1387   gboolean found;
1388
1389   if (strcmp (name, e->components[depth]) == 0)
1390     return TRUE;
1391
1392   if (!e->ignore_case)
1393     return FALSE;
1394
1395   case_folded = g_utf8_casefold (name, -1);
1396   key = g_utf8_collate_key (case_folded, -1);
1397
1398   found = strcmp (key, e->case_components[depth]) == 0;
1399
1400   g_free (case_folded);
1401   g_free (key);
1402
1403   return found;
1404 }
1405
1406 static GFile *
1407 next_match_recurse (Enumerator *e,
1408                     gint        depth)
1409 {
1410   GFile *file;
1411   GFileInfo *info;
1412   const gchar *name;
1413
1414   while (TRUE)
1415     {
1416       if (e->enumerators[depth] == NULL)
1417         {
1418           if (depth > 0)
1419             {
1420               file = next_match_recurse (e, depth - 1);
1421               if (file)
1422                 {
1423                   e->children[depth] = file;
1424                   e->enumerators[depth] = g_file_enumerate_children (file,
1425                                                                      G_FILE_ATTRIBUTE_STANDARD_NAME,
1426                                                                      G_FILE_QUERY_INFO_NONE,
1427                                                                      NULL,
1428                                                                      NULL);
1429                 }
1430             }
1431           if (e->enumerators[depth] == NULL)
1432             return NULL;
1433         }
1434
1435       while ((info = g_file_enumerator_next_file (e->enumerators[depth], NULL, NULL)))
1436         {
1437           name = g_file_info_get_name (info);
1438           if (component_match (e, depth, name))
1439             {
1440               file = g_file_get_child (e->children[depth], name);
1441               g_object_unref (info);
1442               return file;
1443             }
1444           g_object_unref (info);
1445         }
1446
1447       g_object_unref (e->enumerators[depth]);
1448       e->enumerators[depth] = NULL;
1449       g_object_unref (e->children[depth]);
1450       e->children[depth] = NULL;
1451     }
1452 }
1453
1454 static GFile *
1455 enumerator_next (Enumerator *e)
1456 {
1457   return next_match_recurse (e, e->depth - 1);
1458 }
1459
1460 static Enumerator *
1461 enumerator_new (GFile      *root,
1462                 const char *path,
1463                 gboolean    ignore_case)
1464 {
1465   Enumerator *e;
1466   gint i;
1467   gchar *case_folded;
1468
1469   e = g_new0 (Enumerator, 1);
1470   e->path = g_strdup (path);
1471   e->ignore_case = ignore_case;
1472
1473   e->components = g_strsplit (e->path, G_DIR_SEPARATOR_S, -1);
1474   e->depth = g_strv_length (e->components);
1475   if (e->ignore_case)
1476     {
1477       e->case_components = g_new0 (char *, e->depth + 1);
1478       for (i = 0; e->components[i]; i++)
1479         {
1480           case_folded = g_utf8_casefold (e->components[i], -1);
1481           e->case_components[i] = g_utf8_collate_key (case_folded, -1);
1482           g_free (case_folded);
1483         }
1484     }
1485
1486   e->children = g_new0 (GFile *, e->depth);
1487   e->children[0] = g_object_ref (root);
1488   e->enumerators = g_new0 (GFileEnumerator *, e->depth);
1489   e->enumerators[0] = g_file_enumerate_children (root,
1490                                                  G_FILE_ATTRIBUTE_STANDARD_NAME,
1491                                                  G_FILE_QUERY_INFO_NONE,
1492                                                  NULL,
1493                                                  NULL);
1494
1495   return e;
1496 }
1497
1498 static void
1499 enumerator_free (Enumerator *e)
1500 {
1501   gint i;
1502
1503   for (i = 0; i < e->depth; i++)
1504     {
1505       if (e->enumerators[i])
1506         g_object_unref (e->enumerators[i]);
1507       if (e->children[i])
1508         g_object_unref (e->children[i]);
1509     }
1510
1511   g_free (e->enumerators);
1512   g_free (e->children);
1513   g_strfreev (e->components);
1514   if (e->case_components)
1515     g_strfreev (e->case_components);
1516   g_free (e->path);
1517   g_free (e);
1518 }
1519
1520 static gboolean
1521 matchlet_match (TreeMatchlet *matchlet,
1522                 GFile        *root)
1523 {
1524   GFile *file;
1525   GFileInfo *info;
1526   gboolean result;
1527   const gchar *attrs;
1528   Enumerator *e;
1529   GList *l;
1530
1531   e = enumerator_new (root, matchlet->path, !matchlet->match_case);
1532
1533   do
1534     {
1535       file = enumerator_next (e);
1536       if (!file)
1537         {
1538           enumerator_free (e);
1539           return FALSE;
1540         }
1541
1542       if (matchlet->mimetype)
1543         attrs = G_FILE_ATTRIBUTE_STANDARD_TYPE ","
1544                 G_FILE_ATTRIBUTE_ACCESS_CAN_EXECUTE ","
1545                 G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE;
1546       else
1547         attrs = G_FILE_ATTRIBUTE_STANDARD_TYPE ","
1548                 G_FILE_ATTRIBUTE_ACCESS_CAN_EXECUTE;
1549       info = g_file_query_info (file,
1550                                 attrs,
1551                                 G_FILE_QUERY_INFO_NONE,
1552                                 NULL,
1553                                 NULL);
1554       if (info)
1555         {
1556           result = TRUE;
1557
1558           if (matchlet->type != G_FILE_TYPE_UNKNOWN &&
1559               g_file_info_get_file_type (info) != matchlet->type)
1560             result = FALSE;
1561
1562           if (matchlet->executable &&
1563               !g_file_info_get_attribute_boolean (info, G_FILE_ATTRIBUTE_ACCESS_CAN_EXECUTE))
1564             result = FALSE;
1565         }
1566       else
1567         result = FALSE;
1568
1569       if (result && matchlet->non_empty)
1570         {
1571           GFileEnumerator *child_enum;
1572           GFileInfo *child_info;
1573
1574           child_enum = g_file_enumerate_children (file,
1575                                                   G_FILE_ATTRIBUTE_STANDARD_NAME,
1576                                                   G_FILE_QUERY_INFO_NONE,
1577                                                   NULL,
1578                                                   NULL);
1579
1580           if (child_enum)
1581             {
1582               child_info = g_file_enumerator_next_file (child_enum, NULL, NULL);
1583               if (child_info)
1584                 g_object_unref (child_info);
1585               else
1586                 result = FALSE;
1587               g_object_unref (child_enum);
1588             }
1589           else
1590             result = FALSE;
1591         }
1592
1593       if (result && matchlet->mimetype)
1594         {
1595           if (strcmp (matchlet->mimetype, g_file_info_get_content_type (info)) != 0)
1596             result = FALSE;
1597         }
1598
1599       g_object_unref (info);
1600       g_object_unref (file);
1601     }
1602   while (!result);
1603
1604   enumerator_free (e);
1605
1606   if (!matchlet->matches)
1607     return TRUE;
1608
1609   for (l = matchlet->matches; l; l = l->next)
1610     {
1611       TreeMatchlet *submatchlet;
1612
1613       submatchlet = l->data;
1614       if (matchlet_match (submatchlet, root))
1615         return TRUE;
1616     }
1617
1618   return FALSE;
1619 }
1620
1621 static void
1622 match_match (TreeMatch    *match,
1623              GFile        *root,
1624              GPtrArray    *types)
1625 {
1626   GList *l;
1627
1628   for (l = match->matches; l; l = l->next)
1629     {
1630       TreeMatchlet *matchlet = l->data;
1631       if (matchlet_match (matchlet, root))
1632         {
1633           g_ptr_array_add (types, g_strdup (match->contenttype));
1634           break;
1635         }
1636     }
1637 }
1638
1639 /**
1640  * g_content_type_guess_for_tree:
1641  * @root: the root of the tree to guess a type for
1642  *
1643  * Tries to guess the type of the tree with root @root, by
1644  * looking at the files it contains. The result is an array
1645  * of content types, with the best guess coming first.
1646  *
1647  * The types returned all have the form x-content/foo, e.g.
1648  * x-content/audio-cdda (for audio CDs) or x-content/image-dcf
1649  * (for a camera memory card). See the <ulink url="http://www.freedesktop.org/wiki/Specifications/shared-mime-info-spec">shared-mime-info</ulink>
1650  * specification for more on x-content types.
1651  *
1652  * This function is useful in the implementation of
1653  * g_mount_guess_content_type().
1654  *
1655  * Returns: (transfer full) (array zero-terminated=1): an %NULL-terminated
1656  *     array of zero or more content types, or %NULL. Free with g_strfreev()
1657  *
1658  * Since: 2.18
1659  */
1660 gchar **
1661 g_content_type_guess_for_tree (GFile *root)
1662 {
1663   GPtrArray *types;
1664   GList *l;
1665
1666   types = g_ptr_array_new ();
1667
1668   G_LOCK (gio_treemagic);
1669
1670   tree_magic_init ();
1671   for (l = tree_matches; l; l = l->next)
1672     {
1673       TreeMatch *match = l->data;
1674       match_match (match, root, types);
1675     }
1676
1677   G_UNLOCK (gio_treemagic);
1678
1679   g_ptr_array_add (types, NULL);
1680
1681   return (gchar **)g_ptr_array_free (types, FALSE);
1682 }
1683
1684 #endif /* Unix version */