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-rw-r--r--lib/xdgmime/xdgmimecache.c895
1 files changed, 895 insertions, 0 deletions
diff --git a/lib/xdgmime/xdgmimecache.c b/lib/xdgmime/xdgmimecache.c
new file mode 100644
index 0000000..8804eab
--- /dev/null
+++ b/lib/xdgmime/xdgmimecache.c
@@ -0,0 +1,895 @@
+/* -*- mode: C; c-file-style: "gnu" -*- */
+/* xdgmimealias.c: Private file. mmappable caches for mime data
+ *
+ * More info can be found at http://www.freedesktop.org/standards/
+ *
+ * Copyright (C) 2005 Matthias Clasen <mclasen@redhat.com>
+ *
+ * Licensed under the Academic Free License version 2.0
+ * Or under the following terms:
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <fnmatch.h>
+#include <assert.h>
+
+#include <netinet/in.h> /* for ntohl/ntohs */
+
+#ifdef HAVE_MMAP
+#include <sys/mman.h>
+#endif
+
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "xdgmimecache.h"
+#include "xdgmimeint.h"
+
+#ifndef MAX
+#define MAX(a,b) ((a) > (b) ? (a) : (b))
+#endif
+
+#ifndef FALSE
+#define FALSE (0)
+#endif
+
+#ifndef TRUE
+#define TRUE (!FALSE)
+#endif
+
+#ifndef _O_BINARY
+#define _O_BINARY 0
+#endif
+
+#ifndef MAP_FAILED
+#define MAP_FAILED ((void *) -1)
+#endif
+
+#define MAJOR_VERSION 1
+#define MINOR_VERSION 0
+
+struct _XdgMimeCache
+{
+ int ref_count;
+
+ size_t size;
+ char *buffer;
+};
+
+#define GET_UINT16(cache,offset) (ntohs(*(xdg_uint16_t*)((cache) + (offset))))
+#define GET_UINT32(cache,offset) (ntohl(*(xdg_uint32_t*)((cache) + (offset))))
+
+XdgMimeCache *
+_xdg_mime_cache_ref (XdgMimeCache *cache)
+{
+ cache->ref_count++;
+ return cache;
+}
+
+void
+_xdg_mime_cache_unref (XdgMimeCache *cache)
+{
+ cache->ref_count--;
+
+ if (cache->ref_count == 0)
+ {
+#ifdef HAVE_MMAP
+ munmap (cache->buffer, cache->size);
+#endif
+ free (cache);
+ }
+}
+
+XdgMimeCache *
+_xdg_mime_cache_new_from_file (const char *file_name)
+{
+ XdgMimeCache *cache = NULL;
+
+#ifdef HAVE_MMAP
+ int fd = -1;
+ struct stat st;
+ char *buffer = NULL;
+
+ /* Open the file and map it into memory */
+ fd = open (file_name, O_RDONLY|_O_BINARY, 0);
+
+ if (fd < 0)
+ return NULL;
+
+ if (fstat (fd, &st) < 0 || st.st_size < 4)
+ goto done;
+
+ buffer = (char *) mmap (NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
+
+ if (buffer == MAP_FAILED)
+ goto done;
+
+ /* Verify version */
+ if (GET_UINT16 (buffer, 0) != MAJOR_VERSION ||
+ GET_UINT16 (buffer, 2) != MINOR_VERSION)
+ {
+ munmap (buffer, st.st_size);
+
+ goto done;
+ }
+
+ cache = (XdgMimeCache *) malloc (sizeof (XdgMimeCache));
+ cache->ref_count = 1;
+ cache->buffer = buffer;
+ cache->size = st.st_size;
+
+ done:
+ if (fd != -1)
+ close (fd);
+
+#endif /* HAVE_MMAP */
+
+ return cache;
+}
+
+static int
+cache_magic_matchlet_compare_to_data (XdgMimeCache *cache,
+ xdg_uint32_t offset,
+ const void *data,
+ size_t len)
+{
+ xdg_uint32_t range_start = GET_UINT32 (cache->buffer, offset);
+ xdg_uint32_t range_length = GET_UINT32 (cache->buffer, offset + 4);
+ xdg_uint32_t data_length = GET_UINT32 (cache->buffer, offset + 12);
+ xdg_uint32_t data_offset = GET_UINT32 (cache->buffer, offset + 16);
+ xdg_uint32_t mask_offset = GET_UINT32 (cache->buffer, offset + 20);
+
+ int i, j;
+
+ for (i = range_start; i <= range_start + range_length; i++)
+ {
+ int valid_matchlet = TRUE;
+
+ if (i + data_length > len)
+ return FALSE;
+
+ if (mask_offset)
+ {
+ for (j = 0; j < data_length; j++)
+ {
+ if ((((unsigned char *)cache->buffer)[data_offset + j] & ((unsigned char *)cache->buffer)[mask_offset + j]) !=
+ ((((unsigned char *) data)[j + i]) & ((unsigned char *)cache->buffer)[mask_offset + j]))
+ {
+ valid_matchlet = FALSE;
+ break;
+ }
+ }
+ }
+ else
+ {
+ for (j = 0; j < data_length; j++)
+ {
+ if (((unsigned char *)cache->buffer)[data_offset + j] != ((unsigned char *) data)[j + i])
+ {
+ valid_matchlet = FALSE;
+ break;
+ }
+ }
+ }
+
+ if (valid_matchlet)
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+static int
+cache_magic_matchlet_compare (XdgMimeCache *cache,
+ xdg_uint32_t offset,
+ const void *data,
+ size_t len)
+{
+ xdg_uint32_t n_children = GET_UINT32 (cache->buffer, offset + 24);
+ xdg_uint32_t child_offset = GET_UINT32 (cache->buffer, offset + 28);
+
+ int i;
+
+ if (cache_magic_matchlet_compare_to_data (cache, offset, data, len))
+ {
+ if (n_children == 0)
+ return TRUE;
+
+ for (i = 0; i < n_children; i++)
+ {
+ if (cache_magic_matchlet_compare (cache, child_offset + 32 * i,
+ data, len))
+ return TRUE;
+ }
+ }
+
+ return FALSE;
+}
+
+static const char *
+cache_magic_compare_to_data (XdgMimeCache *cache,
+ xdg_uint32_t offset,
+ const void *data,
+ size_t len,
+ int *prio)
+{
+ xdg_uint32_t priority = GET_UINT32 (cache->buffer, offset);
+ xdg_uint32_t mimetype_offset = GET_UINT32 (cache->buffer, offset + 4);
+ xdg_uint32_t n_matchlets = GET_UINT32 (cache->buffer, offset + 8);
+ xdg_uint32_t matchlet_offset = GET_UINT32 (cache->buffer, offset + 12);
+
+ int i;
+
+ for (i = 0; i < n_matchlets; i++)
+ {
+ if (cache_magic_matchlet_compare (cache, matchlet_offset + i * 32,
+ data, len))
+ {
+ *prio = priority;
+
+ return cache->buffer + mimetype_offset;
+ }
+ }
+
+ return NULL;
+}
+
+static const char *
+cache_magic_lookup_data (XdgMimeCache *cache,
+ const void *data,
+ size_t len,
+ int *prio,
+ const char *mime_types[],
+ int n_mime_types)
+{
+ xdg_uint32_t list_offset;
+ xdg_uint32_t n_entries;
+ xdg_uint32_t offset;
+
+ int j, n;
+
+ *prio = 0;
+
+ list_offset = GET_UINT32 (cache->buffer, 24);
+ n_entries = GET_UINT32 (cache->buffer, list_offset);
+ offset = GET_UINT32 (cache->buffer, list_offset + 8);
+
+ for (j = 0; j < n_entries; j++)
+ {
+ const char *match;
+
+ match = cache_magic_compare_to_data (cache, offset + 16 * j,
+ data, len, prio);
+ if (match)
+ return match;
+ else
+ {
+ xdg_uint32_t mimetype_offset;
+ const char *non_match;
+
+ mimetype_offset = GET_UINT32 (cache->buffer, offset + 16 * j + 4);
+ non_match = cache->buffer + mimetype_offset;
+
+ for (n = 0; n < n_mime_types; n++)
+ {
+ if (mime_types[n] &&
+ xdg_mime_mime_type_equal (mime_types[n], non_match))
+ mime_types[n] = NULL;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+static const char *
+cache_alias_lookup (const char *alias)
+{
+ const char *ptr;
+ int i, min, max, mid, cmp;
+
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+ xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 4);
+ xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
+ xdg_uint32_t offset;
+
+ min = 0;
+ max = n_entries - 1;
+ while (max >= min)
+ {
+ mid = (min + max) / 2;
+
+ offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid);
+ ptr = cache->buffer + offset;
+ cmp = strcmp (ptr, alias);
+
+ if (cmp < 0)
+ min = mid + 1;
+ else if (cmp > 0)
+ max = mid - 1;
+ else
+ {
+ offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid + 4);
+ return cache->buffer + offset;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+static int
+cache_glob_lookup_literal (const char *file_name,
+ const char *mime_types[],
+ int n_mime_types)
+{
+ const char *ptr;
+ int i, min, max, mid, cmp;
+
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+ xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 12);
+ xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
+ xdg_uint32_t offset;
+
+ min = 0;
+ max = n_entries - 1;
+ while (max >= min)
+ {
+ mid = (min + max) / 2;
+
+ offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid);
+ ptr = cache->buffer + offset;
+ cmp = strcmp (ptr, file_name);
+
+ if (cmp < 0)
+ min = mid + 1;
+ else if (cmp > 0)
+ max = mid - 1;
+ else
+ {
+ offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid + 4);
+ mime_types[0] = (const char *)(cache->buffer + offset);
+
+ return 1;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int
+cache_glob_lookup_fnmatch (const char *file_name,
+ const char *mime_types[],
+ int n_mime_types)
+{
+ const char *mime_type;
+ const char *ptr;
+
+ int i, j, n;
+
+ n = 0;
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+
+ xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 20);
+ xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
+
+ for (j = 0; j < n_entries && n < n_mime_types; j++)
+ {
+ xdg_uint32_t offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * j);
+ xdg_uint32_t mimetype_offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * j + 4);
+ ptr = cache->buffer + offset;
+ mime_type = cache->buffer + mimetype_offset;
+
+ /* FIXME: Not UTF-8 safe */
+ if (fnmatch (ptr, file_name, 0) == 0)
+ mime_types[n++] = mime_type;
+ }
+
+ if (n > 0)
+ return n;
+ }
+
+ return 0;
+}
+
+static int
+cache_glob_node_lookup_suffix (XdgMimeCache *cache,
+ xdg_uint32_t n_entries,
+ xdg_uint32_t offset,
+ const char *suffix,
+ int ignore_case,
+ const char *mime_types[],
+ int n_mime_types)
+{
+ xdg_unichar_t character;
+ xdg_unichar_t match_char;
+ xdg_uint32_t mimetype_offset;
+ xdg_uint32_t n_children;
+ xdg_uint32_t child_offset;
+
+ int min, max, mid, n, i;
+
+ character = _xdg_utf8_to_ucs4 (suffix);
+ if (ignore_case)
+ character = _xdg_ucs4_to_lower (character);
+
+ min = 0;
+ max = n_entries - 1;
+ while (max >= min)
+ {
+ mid = (min + max) / 2;
+
+ match_char = GET_UINT32 (cache->buffer, offset + 16 * mid);
+
+ if (match_char < character)
+ min = mid + 1;
+ else if (match_char > character)
+ max = mid - 1;
+ else
+ {
+ suffix = _xdg_utf8_next_char (suffix);
+ if (*suffix == '\0')
+ {
+ mimetype_offset = GET_UINT32 (cache->buffer, offset + 16 * mid + 4);
+ n = 0;
+ if (mimetype_offset)
+ mime_types[n++] = cache->buffer + mimetype_offset;
+
+ n_children = GET_UINT32 (cache->buffer, offset + 16 * mid + 8);
+ child_offset = GET_UINT32 (cache->buffer, offset + 16 * mid + 12);
+ i = 0;
+ while (n < n_mime_types && i < n_children)
+ {
+ match_char = GET_UINT32 (cache->buffer, child_offset + 16 * i);
+ mimetype_offset = GET_UINT32 (cache->buffer, offset + 16 * i + 4);
+ if (match_char != 0)
+ break;
+
+ mime_types[n++] = cache->buffer + mimetype_offset;
+ i++;
+ }
+
+ return n;
+ }
+ else
+ {
+ n_children = GET_UINT32 (cache->buffer, offset + 16 * mid + 8);
+ child_offset = GET_UINT32 (cache->buffer, offset + 16 * mid + 12);
+
+ return cache_glob_node_lookup_suffix (cache,
+ n_children, child_offset,
+ suffix, ignore_case,
+ mime_types,
+ n_mime_types);
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int
+cache_glob_lookup_suffix (const char *suffix,
+ int ignore_case,
+ const char *mime_types[],
+ int n_mime_types)
+{
+ int i, n;
+
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+
+ xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 16);
+ xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
+ xdg_uint32_t offset = GET_UINT32 (cache->buffer, list_offset + 4);
+
+ n = cache_glob_node_lookup_suffix (cache,
+ n_entries, offset,
+ suffix, ignore_case,
+ mime_types,
+ n_mime_types);
+ if (n > 0)
+ return n;
+ }
+
+ return 0;
+}
+
+static void
+find_stopchars (char *stopchars)
+{
+ int i, j, k, l;
+
+ k = 0;
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+
+ xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 16);
+ xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
+ xdg_uint32_t offset = GET_UINT32 (cache->buffer, list_offset + 4);
+
+ for (j = 0; j < n_entries; j++)
+ {
+ xdg_uint32_t match_char = GET_UINT32 (cache->buffer, offset);
+
+ if (match_char < 128)
+ {
+ for (l = 0; l < k; l++)
+ if (stopchars[l] == match_char)
+ break;
+ if (l == k)
+ {
+ stopchars[k] = (char) match_char;
+ k++;
+ }
+ }
+
+ offset += 16;
+ }
+ }
+
+ stopchars[k] = '\0';
+}
+
+static int
+cache_glob_lookup_file_name (const char *file_name,
+ const char *mime_types[],
+ int n_mime_types)
+{
+ const char *ptr;
+ char stopchars[128];
+ int n;
+
+ assert (file_name != NULL);
+
+ /* First, check the literals */
+ n = cache_glob_lookup_literal (file_name, mime_types, n_mime_types);
+ if (n > 0)
+ return n;
+
+ find_stopchars (stopchars);
+
+ /* Next, check suffixes */
+ ptr = strpbrk (file_name, stopchars);
+ while (ptr)
+ {
+ n = cache_glob_lookup_suffix (ptr, FALSE, mime_types, n_mime_types);
+ if (n > 0)
+ return n;
+
+ n = cache_glob_lookup_suffix (ptr, TRUE, mime_types, n_mime_types);
+ if (n > 0)
+ return n;
+
+ ptr = strpbrk (ptr + 1, stopchars);
+ }
+
+ /* Last, try fnmatch */
+ return cache_glob_lookup_fnmatch (file_name, mime_types, n_mime_types);
+}
+
+int
+_xdg_mime_cache_get_max_buffer_extents (void)
+{
+ xdg_uint32_t offset;
+ xdg_uint32_t max_extent;
+ int i;
+
+ max_extent = 0;
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+
+ offset = GET_UINT32 (cache->buffer, 24);
+ max_extent = MAX (max_extent, GET_UINT32 (cache->buffer, offset + 4));
+ }
+
+ return max_extent;
+}
+
+static const char *
+cache_get_mime_type_for_data (const void *data,
+ size_t len,
+ const char *mime_types[],
+ int n_mime_types)
+{
+ const char *mime_type;
+ int i, n, priority;
+
+ priority = 0;
+ mime_type = NULL;
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+
+ int prio;
+ const char *match;
+
+ match = cache_magic_lookup_data (cache, data, len, &prio,
+ mime_types, n_mime_types);
+ if (prio > priority)
+ {
+ priority = prio;
+ mime_type = match;
+ }
+ }
+
+ if (priority > 0)
+ return mime_type;
+
+ for (n = 0; n < n_mime_types; n++)
+ {
+ if (mime_types[n])
+ return mime_types[n];
+ }
+
+ return XDG_MIME_TYPE_UNKNOWN;
+}
+
+const char *
+_xdg_mime_cache_get_mime_type_for_data (const void *data,
+ size_t len)
+{
+ return cache_get_mime_type_for_data (data, len, NULL, 0);
+}
+
+const char *
+_xdg_mime_cache_get_mime_type_for_file (const char *file_name,
+ struct stat *statbuf)
+{
+ const char *mime_type;
+ const char *mime_types[2];
+ FILE *file;
+ unsigned char *data;
+ int max_extent;
+ int bytes_read;
+ struct stat buf;
+ const char *base_name;
+ int n;
+
+ if (file_name == NULL)
+ return NULL;
+
+ if (! _xdg_utf8_validate (file_name))
+ return NULL;
+
+ base_name = _xdg_get_base_name (file_name);
+ n = cache_glob_lookup_file_name (base_name, mime_types, 2);
+
+ if (n == 1)
+ return mime_types[0];
+
+ if (!statbuf)
+ {
+ if (stat (file_name, &buf) != 0)
+ return XDG_MIME_TYPE_UNKNOWN;
+
+ statbuf = &buf;
+ }
+
+ if (!S_ISREG (statbuf->st_mode))
+ return XDG_MIME_TYPE_UNKNOWN;
+
+ /* FIXME: Need to make sure that max_extent isn't totally broken. This could
+ * be large and need getting from a stream instead of just reading it all
+ * in. */
+ max_extent = _xdg_mime_cache_get_max_buffer_extents ();
+ data = malloc (max_extent);
+ if (data == NULL)
+ return XDG_MIME_TYPE_UNKNOWN;
+
+ file = fopen (file_name, "r");
+ if (file == NULL)
+ {
+ free (data);
+ return XDG_MIME_TYPE_UNKNOWN;
+ }
+
+ bytes_read = fread (data, 1, max_extent, file);
+ if (ferror (file))
+ {
+ free (data);
+ fclose (file);
+ return XDG_MIME_TYPE_UNKNOWN;
+ }
+
+ mime_type = cache_get_mime_type_for_data (data, bytes_read,
+ mime_types, n);
+
+ free (data);
+ fclose (file);
+
+ return mime_type;
+}
+
+const char *
+_xdg_mime_cache_get_mime_type_from_file_name (const char *file_name)
+{
+ const char *mime_type;
+
+ if (cache_glob_lookup_file_name (file_name, &mime_type, 1))
+ return mime_type;
+ else
+ return XDG_MIME_TYPE_UNKNOWN;
+}
+
+#if 1
+static int
+is_super_type (const char *mime)
+{
+ int length;
+ const char *type;
+
+ length = strlen (mime);
+ type = &(mime[length - 2]);
+
+ if (strcmp (type, "/*") == 0)
+ return 1;
+
+ return 0;
+}
+#endif
+
+int
+_xdg_mime_cache_mime_type_subclass (const char *mime,
+ const char *base)
+{
+ const char *umime, *ubase;
+
+ int i, j, min, max, med, cmp;
+
+ umime = _xdg_mime_cache_unalias_mime_type (mime);
+ ubase = _xdg_mime_cache_unalias_mime_type (base);
+
+ if (strcmp (umime, ubase) == 0)
+ return 1;
+
+ /* We really want to handle text/ * in GtkFileFilter, so we just
+ * turn on the supertype matching
+ */
+#if 1
+ /* Handle supertypes */
+ if (is_super_type (ubase) &&
+ xdg_mime_media_type_equal (umime, ubase))
+ return 1;
+#endif
+
+ /* Handle special cases text/plain and application/octet-stream */
+ if (strcmp (ubase, "text/plain") == 0 &&
+ strncmp (umime, "text/", 5) == 0)
+ return 1;
+
+ if (strcmp (ubase, "application/octet-stream") == 0)
+ return 1;
+
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+
+ xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 8);
+ xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
+ xdg_uint32_t offset, n_parents, parent_offset;
+
+ min = 0;
+ max = n_entries - 1;
+ while (max >= min)
+ {
+ med = (min + max)/2;
+
+ offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * med);
+ cmp = strcmp (cache->buffer + offset, umime);
+ if (cmp < 0)
+ min = med + 1;
+ else if (cmp > 0)
+ max = med - 1;
+ else
+ {
+ offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * med + 4);
+ n_parents = GET_UINT32 (cache->buffer, offset);
+
+ for (j = 0; j < n_parents; j++)
+ {
+ parent_offset = GET_UINT32 (cache->buffer, offset + 4 + 4 * j);
+ if (_xdg_mime_cache_mime_type_subclass (cache->buffer + parent_offset, ubase))
+ return 1;
+ }
+
+ break;
+ }
+ }
+ }
+
+ return 0;
+}
+
+const char *
+_xdg_mime_cache_unalias_mime_type (const char *mime)
+{
+ const char *lookup;
+
+ lookup = cache_alias_lookup (mime);
+
+ if (lookup)
+ return lookup;
+
+ return mime;
+}
+
+char **
+_xdg_mime_cache_list_mime_parents (const char *mime)
+{
+ int i, j, k, p;
+ char *all_parents[128]; /* we'll stop at 128 */
+ char **result;
+
+ mime = xdg_mime_unalias_mime_type (mime);
+
+ p = 0;
+ for (i = 0; _caches[i]; i++)
+ {
+ XdgMimeCache *cache = _caches[i];
+
+ xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 8);
+ xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
+
+ for (j = 0; j < n_entries; j++)
+ {
+ xdg_uint32_t mimetype_offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * j);
+ xdg_uint32_t parents_offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * j + 4);
+
+ if (strcmp (cache->buffer + mimetype_offset, mime) == 0)
+ {
+ xdg_uint32_t parent_mime_offset;
+ xdg_uint32_t n_parents = GET_UINT32 (cache->buffer, parents_offset);
+
+ for (k = 0; k < n_parents && p < 127; k++)
+ {
+ parent_mime_offset = GET_UINT32 (cache->buffer, parents_offset + 4 + 4 * k);
+ all_parents[p++] = cache->buffer + parent_mime_offset;
+ }
+
+ break;
+ }
+ }
+ }
+ all_parents[p++] = 0;
+
+ result = (char **) malloc (p * sizeof (char *));
+ memcpy (result, all_parents, p * sizeof (char *));
+
+ return result;
+}
+