diff --git a/gio/xdgmime/xdgmime.c b/gio/xdgmime/xdgmime.c
index dce938a6f..0909581eb 100644
--- a/gio/xdgmime/xdgmime.c
+++ b/gio/xdgmime/xdgmime.c
@@ -6,23 +6,7 @@
  * Copyright (C) 2003,2004  Red Hat, Inc.
  * Copyright (C) 2003,2004  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
@@ -143,7 +127,7 @@ xdg_dir_time_list_free (XdgDirTimeList *list)
 
 static int
 xdg_mime_init_from_directory (const char *directory,
-                              void       *user_data)
+                              void       *user_data __attribute__((__unused__)))
 {
   char *file_name;
   struct stat st;
@@ -836,12 +820,12 @@ xdg_mime_is_super_type (const char *mime)
 int
 _xdg_mime_mime_type_subclass (const char *mime,
 			      const char *base,
-			      const char **seen)
+			      const char ***seen)
 {
   const char *umime, *ubase, *parent;
-  const char **parents;
+  const char **parents, **first_seen = NULL, **new_seen;
 
-  int first_seen = 0, i, ret = 0;
+  int i, ret = 0;
 
   if (_caches)
     return _xdg_mime_cache_mime_type_subclass (mime, base, NULL);
@@ -870,8 +854,8 @@ _xdg_mime_mime_type_subclass (const char *mime,
 
   if (!seen)
     {
-      seen = calloc (1, sizeof (char *));
-      first_seen = 1;
+      first_seen = calloc (1, sizeof (char *));
+      seen = &first_seen;
     }
 
   parents = _xdg_mime_parent_list_lookup (parent_list, umime);
@@ -880,12 +864,15 @@ _xdg_mime_mime_type_subclass (const char *mime,
       parent = *parents;
 
       /* Detect and avoid buggy circular relationships */
-      for (i = 0; seen[i] != NULL; i++)
-        if (parent == seen[i])
+      for (i = 0; (*seen)[i] != NULL; i++)
+        if (parent == (*seen)[i])
           goto next_parent;
-      seen = realloc (seen, (i + 2) * sizeof (char *));
-      seen[i] = parent;
-      seen[i + 1] = NULL;
+      new_seen = realloc (*seen, (i + 2) * sizeof (char *));
+      if (!new_seen)
+        goto done;
+      new_seen[i] = parent;
+      new_seen[i + 1] = NULL;
+      *seen = new_seen;
 
       if (_xdg_mime_mime_type_subclass (parent, ubase, seen))
         {
@@ -898,8 +885,7 @@ _xdg_mime_mime_type_subclass (const char *mime,
     }
 
 done:
-  if (first_seen)
-    free (seen);
+  free (first_seen);
   return ret;
 }
 
@@ -919,6 +905,8 @@ xdg_mime_list_mime_parents (const char *mime)
   char **result;
   int i, n;
 
+  xdg_mime_init ();
+
   if (_caches)
     return _xdg_mime_cache_list_mime_parents (mime);
 
diff --git a/gio/xdgmime/xdgmime.h b/gio/xdgmime/xdgmime.h
index bbae1be79..093b12aa3 100644
--- a/gio/xdgmime/xdgmime.h
+++ b/gio/xdgmime/xdgmime.h
@@ -6,23 +6,7 @@
  * Copyright (C) 2003  Red Hat, Inc.
  * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 
@@ -126,7 +110,7 @@ int          _xdg_mime_mime_type_equal             (const char *mime_a,
 						    const char *mime_b);
 int          _xdg_mime_mime_type_subclass          (const char *mime,
 						    const char *base,
-						    const char **seen);
+						    const char ***seen);
 const char  *_xdg_mime_unalias_mime_type           (const char *mime);
 
 
diff --git a/gio/xdgmime/xdgmimealias.c b/gio/xdgmime/xdgmimealias.c
index 0fc51f94c..857d274a3 100644
--- a/gio/xdgmime/xdgmimealias.c
+++ b/gio/xdgmime/xdgmimealias.c
@@ -6,23 +6,7 @@
  * Copyright (C) 2004  Red Hat, Inc.
  * Copyright (C) 2004  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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/gio/xdgmime/xdgmimealias.h b/gio/xdgmime/xdgmimealias.h
index 6e0cfff3b..05df00991 100644
--- a/gio/xdgmime/xdgmimealias.h
+++ b/gio/xdgmime/xdgmimealias.h
@@ -6,23 +6,7 @@
  * Copyright (C) 2004  Red Hat, Inc.
  * Copyright (C) 200  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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifndef __XDG_MIME_ALIAS_H__
diff --git a/gio/xdgmime/xdgmimecache.c b/gio/xdgmime/xdgmimecache.c
index 9ea10f901..f7eddcbe6 100644
--- a/gio/xdgmime/xdgmimecache.c
+++ b/gio/xdgmime/xdgmimecache.c
@@ -5,23 +5,7 @@
  *
  * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
@@ -92,6 +76,13 @@ struct _XdgMimeCache
 #define GET_UINT16(cache,offset) (ntohs(*(xdg_uint16_t*)((cache) + (offset))))
 #define GET_UINT32(cache,offset) (ntohl(*(xdg_uint32_t*)((cache) + (offset))))
 
+// Validates that it is safe to call GET_UINT32() at
+// cache->buffer[offset + (n * record_size)]. Ensures that offset is aligned to
+// a 4-byte boundary, and that offset+(n*record_size) does not overflow.
+// `record_size` values are known constants and never 0.
+#define OUT_OF_BOUNDS(offset,n,record_size,max) \
+  (((offset) & 0x3) || (offset) > (max) || (n) > ((max) - (offset)) / (record_size))
+
 XdgMimeCache *
 _xdg_mime_cache_ref (XdgMimeCache *cache)
 {
@@ -132,7 +123,8 @@ _xdg_mime_cache_new_from_file (const char *file_name)
   if (fd < 0)
     return NULL;
   
-  if (fstat (fd, &st) < 0 || st.st_size < 4)
+  // A valid cache must be at least 40 bytes for the header.
+  if (fstat (fd, &st) < 0 || st.st_size < 40)
     goto done;
 
   buffer = (char *) mmap (NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
@@ -225,6 +217,8 @@ cache_magic_matchlet_compare (XdgMimeCache *cache,
 {
   xdg_uint32_t n_children = GET_UINT32 (cache->buffer, offset + 24);
   xdg_uint32_t child_offset = GET_UINT32 (cache->buffer, offset + 28);
+  if (OUT_OF_BOUNDS (child_offset, n_children, 32, cache->size))
+    return FALSE;
 
   xdg_uint32_t i;
   
@@ -255,6 +249,8 @@ cache_magic_compare_to_data (XdgMimeCache *cache,
   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);
+  if (OUT_OF_BOUNDS (matchlet_offset, n_matchlets, 32, cache->size))
+    return NULL;
 
   xdg_uint32_t i;
 
@@ -287,8 +283,13 @@ cache_magic_lookup_data (XdgMimeCache *cache,
   *prio = 0;
 
   list_offset = GET_UINT32 (cache->buffer, 24);
+  if (OUT_OF_BOUNDS (list_offset, 1, 12, cache->size))
+    return NULL;
+
   n_entries = GET_UINT32 (cache->buffer, list_offset);
   offset = GET_UINT32 (cache->buffer, list_offset + 8);
+  if (OUT_OF_BOUNDS (offset, n_entries, 16, cache->size))
+    return NULL;
   
   for (j = 0; j < n_entries; j++)
     {
@@ -320,7 +321,12 @@ cache_alias_lookup (const char *alias)
         continue;
 
       list_offset = GET_UINT32 (cache->buffer, 4);
+      if (OUT_OF_BOUNDS (list_offset, 1, 4, cache->size))
+        continue;
+
       n_entries = GET_UINT32 (cache->buffer, list_offset);
+      if (OUT_OF_BOUNDS (list_offset + 4, n_entries, 8, cache->size))
+        continue;
 
       min = 0; 
       max = n_entries - 1;
@@ -361,6 +367,8 @@ cache_glob_lookup_literal (const char *file_name,
   const char *ptr;
   int i, min, max, mid, cmp;
 
+  assert (n_mime_types > 0);
+
   for (i = 0; _caches[i]; i++)
     {
       XdgMimeCache *cache = _caches[i];
@@ -372,7 +380,12 @@ cache_glob_lookup_literal (const char *file_name,
         continue;
 
       list_offset = GET_UINT32 (cache->buffer, 12);
+      if (OUT_OF_BOUNDS (list_offset, 1, 4, cache->size))
+        continue;
+
       n_entries = GET_UINT32 (cache->buffer, list_offset);
+      if (OUT_OF_BOUNDS (list_offset + 4, n_entries, 12, cache->size))
+        continue;
 
       min = 0; 
       max = n_entries - 1;
@@ -433,7 +446,12 @@ cache_glob_lookup_fnmatch (const char *file_name,
         continue;
 
       list_offset = GET_UINT32 (cache->buffer, 20);
+      if (OUT_OF_BOUNDS (list_offset, 1, 4, cache->size))
+        continue;
+
       n_entries = GET_UINT32 (cache->buffer, list_offset);
+      if (OUT_OF_BOUNDS (list_offset + 4, n_entries, 12, cache->size))
+        continue;
 
       for (j = 0; j < n_entries && n < n_mime_types; j++)
 	{
@@ -504,6 +522,8 @@ cache_glob_node_lookup_suffix (XdgMimeCache  *cache,
           n = 0;
           n_children = GET_UINT32 (cache->buffer, offset + 12 * mid + 4);
           child_offset = GET_UINT32 (cache->buffer, offset + 12 * mid + 8);
+          if (OUT_OF_BOUNDS (child_offset, n_children, 12, cache->size))
+            continue;
       
           if (len > 0)
             {
@@ -565,8 +585,13 @@ cache_glob_lookup_suffix (const char *file_name,
         continue;
 
       list_offset = GET_UINT32 (cache->buffer, 16);
+      if (OUT_OF_BOUNDS (list_offset, 1, 8, cache->size))
+        continue;
+
       n_entries = GET_UINT32 (cache->buffer, list_offset);
       offset = GET_UINT32 (cache->buffer, list_offset + 4);
+      if (OUT_OF_BOUNDS (offset, n_entries, 12, cache->size))
+        continue;
 
       n += cache_glob_node_lookup_suffix (cache,
 					  n_entries, offset,
@@ -707,6 +732,9 @@ _xdg_mime_cache_get_max_buffer_extents (void)
         continue;
 
       offset = GET_UINT32 (cache->buffer, 24);
+      if (OUT_OF_BOUNDS (offset, 1, 8, cache->size))
+        continue;
+
       max_extent = MAX (max_extent, GET_UINT32 (cache->buffer, offset + 4));
     }
 
@@ -902,12 +930,13 @@ is_super_type (const char *mime)
 int
 _xdg_mime_cache_mime_type_subclass (const char *mime,
 				    const char *base,
-				    const char **seen)
+				    const char ***seen)
 {
   const char *umime, *ubase, *parent;
+  const char **first_seen = NULL, **new_seen;
 
   xdg_uint32_t j;
-  int i, k, min, max, med, cmp, first_seen = 0, ret = 0;
+  int i, k, min, max, med, cmp, ret = 0;
 
   umime = _xdg_mime_cache_unalias_mime_type (mime);
   ubase = _xdg_mime_cache_unalias_mime_type (base);
@@ -936,8 +965,8 @@ _xdg_mime_cache_mime_type_subclass (const char *mime,
 
   if (!seen)
     {
-      seen = calloc (1, sizeof (char *));
-      first_seen = 1;
+      first_seen = calloc (1, sizeof (char *));
+      seen = &first_seen;
     }
 
   for (i = 0; _caches[i]; i++)
@@ -951,7 +980,12 @@ _xdg_mime_cache_mime_type_subclass (const char *mime,
         continue;
 
       list_offset = GET_UINT32 (cache->buffer, 8);
+      if (OUT_OF_BOUNDS (list_offset, 1, 4, cache->size))
+        continue;
+
       n_entries = GET_UINT32 (cache->buffer, list_offset);
+      if (OUT_OF_BOUNDS (list_offset + 4, n_entries, 8, cache->size))
+        continue;
 
       min = 0; 
       max = n_entries - 1;
@@ -976,12 +1010,15 @@ _xdg_mime_cache_mime_type_subclass (const char *mime,
 		  parent = cache->buffer + parent_offset;
 
 		  /* Detect and avoid buggy circular relationships */
-		  for (k = 0; seen[k] != NULL; k++)
-		    if (parent == seen[k])
+		  for (k = 0; (*seen)[k] != NULL; k++)
+		    if (parent == (*seen)[k])
 		      goto next_parent;
-		  seen = realloc (seen, (k + 2) * sizeof (char *));
-		  seen[k] = parent;
-		  seen[k + 1] = NULL;
+		  new_seen = realloc (*seen, (k + 2) * sizeof (char *));
+		  if (!new_seen)
+		    goto done;
+		  new_seen[k] = parent;
+		  new_seen[k + 1] = NULL;
+		  *seen = new_seen;
 
 		  if (_xdg_mime_cache_mime_type_subclass (parent, ubase, seen))
 		    {
@@ -999,8 +1036,7 @@ _xdg_mime_cache_mime_type_subclass (const char *mime,
     }
 
 done:
-  if (first_seen)
-    free (seen);
+  free (first_seen);
   return ret;
 }
 
@@ -1038,7 +1074,12 @@ _xdg_mime_cache_list_mime_parents (const char *mime)
         continue;
 
       list_offset = GET_UINT32 (cache->buffer, 8);
+      if (OUT_OF_BOUNDS (list_offset, 1, 4, cache->size))
+        continue;
+
       n_entries = GET_UINT32 (cache->buffer, list_offset);
+      if (OUT_OF_BOUNDS (list_offset + 4, n_entries, 8, cache->size))
+        continue;
 
       for (j = 0; j < n_entries; j++)
 	{
@@ -1080,7 +1121,7 @@ _xdg_mime_cache_list_mime_parents (const char *mime)
 }
 
 static const char *
-cache_lookup_icon (const char *mime, int header)
+cache_lookup_icon (const char *mime, size_t header)
 {
   const char *ptr;
   int i, min, max, mid, cmp;
@@ -1095,8 +1136,16 @@ cache_lookup_icon (const char *mime, int header)
       if (cache->buffer == NULL)
         continue;
 
+      if (OUT_OF_BOUNDS (header, 1, 4, cache->size))
+        continue;
+
       list_offset = GET_UINT32 (cache->buffer, header);
+      if (OUT_OF_BOUNDS (list_offset, 1, 4, cache->size))
+        continue;
+
       n_entries = GET_UINT32 (cache->buffer, list_offset);
+      if (OUT_OF_BOUNDS (list_offset + 4, n_entries, 8, cache->size))
+        continue;
 
       min = 0; 
       max = n_entries - 1;
@@ -1151,6 +1200,9 @@ dump_glob_node (XdgMimeCache *cache,
   mime_offset = GET_UINT32 (cache->buffer, offset + 4);
   n_children = GET_UINT32 (cache->buffer, offset + 8);
   child_offset = GET_UINT32 (cache->buffer, offset + 12);
+  if (OUT_OF_BOUNDS (child_offset, n_children, 20, cache->size))
+    return;
+
   for (i = 0; i < depth; i++)
     printf (" ");
   printf ("%c", character);
@@ -1175,12 +1227,18 @@ _xdg_mime_cache_glob_dump (void)
     xdg_uint32_t n_entries;
     xdg_uint32_t offset;
 
-      if (cache->buffer == NULL)
-        continue;
+    if (cache->buffer == NULL)
+      continue;
 
     list_offset = GET_UINT32 (cache->buffer, 16);
+    if (OUT_OF_BOUNDS (list_offset, 1, 8, cache->size))
+      return;
+
     n_entries = GET_UINT32 (cache->buffer, list_offset);
     offset = GET_UINT32 (cache->buffer, list_offset + 4);
+    if (OUT_OF_BOUNDS (offset, n_entries, 20, cache->size))
+      return;
+
     for (j = 0; j < n_entries; j++)
 	    dump_glob_node (cache, offset + 20 * j, 0);
   }
diff --git a/gio/xdgmime/xdgmimecache.h b/gio/xdgmime/xdgmimecache.h
index 0ac0b054f..de7e5313b 100644
--- a/gio/xdgmime/xdgmimecache.h
+++ b/gio/xdgmime/xdgmimecache.h
@@ -5,23 +5,7 @@
  *
  * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifndef __XDG_MIME_CACHE_H__
@@ -71,7 +55,7 @@ int          _xdg_mime_cache_media_type_equal             (const char *mime_a,
 							   const char *mime_b);
 int          _xdg_mime_cache_mime_type_subclass           (const char *mime_a,
 							   const char *mime_b,
-							   const char **seen);
+							   const char ***seen);
 char       **_xdg_mime_cache_list_mime_parents		  (const char *mime);
 const char  *_xdg_mime_cache_unalias_mime_type            (const char *mime);
 int          _xdg_mime_cache_get_max_buffer_extents       (void);
diff --git a/gio/xdgmime/xdgmimeglob.c b/gio/xdgmime/xdgmimeglob.c
index d68435c89..e84580873 100644
--- a/gio/xdgmime/xdgmimeglob.c
+++ b/gio/xdgmime/xdgmimeglob.c
@@ -6,23 +6,7 @@
  * Copyright (C) 2003  Red Hat, Inc.
  * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/gio/xdgmime/xdgmimeglob.h b/gio/xdgmime/xdgmimeglob.h
index 8b1fa3ad4..7ecee9a8f 100644
--- a/gio/xdgmime/xdgmimeglob.h
+++ b/gio/xdgmime/xdgmimeglob.h
@@ -6,23 +6,7 @@
  * Copyright (C) 2003  Red Hat, Inc.
  * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifndef __XDG_MIME_GLOB_H__
diff --git a/gio/xdgmime/xdgmimeicon.c b/gio/xdgmime/xdgmimeicon.c
index feb6c869c..4aaa564f1 100644
--- a/gio/xdgmime/xdgmimeicon.c
+++ b/gio/xdgmime/xdgmimeicon.c
@@ -5,23 +5,7 @@
  *
  * Copyright (C) 2008  Red Hat, Inc.
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/gio/xdgmime/xdgmimeicon.h b/gio/xdgmime/xdgmimeicon.h
index c416b3c5e..f7244305a 100644
--- a/gio/xdgmime/xdgmimeicon.h
+++ b/gio/xdgmime/xdgmimeicon.h
@@ -5,23 +5,7 @@
  *
  * Copyright (C) 2008  Red Hat, Inc.
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifndef __XDG_MIME_ICON_H__
diff --git a/gio/xdgmime/xdgmimeint.c b/gio/xdgmime/xdgmimeint.c
index 5e4513c50..f7ab067db 100644
--- a/gio/xdgmime/xdgmimeint.c
+++ b/gio/xdgmime/xdgmimeint.c
@@ -6,23 +6,7 @@
  * Copyright (C) 2003  Red Hat, Inc.
  * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
@@ -131,7 +115,7 @@ _xdg_ucs4_to_lower (xdg_unichar_t source)
 }
 
 int
-_xdg_utf8_validate (const char *source)
+_xdg_utf8_validate (const char *source __attribute__((unused)))
 {
   /* FIXME: actually write */
   return TRUE;
diff --git a/gio/xdgmime/xdgmimeint.h b/gio/xdgmime/xdgmimeint.h
index 9a8256d17..041c4f489 100644
--- a/gio/xdgmime/xdgmimeint.h
+++ b/gio/xdgmime/xdgmimeint.h
@@ -6,23 +6,7 @@
  * Copyright (C) 2003  Red Hat, Inc.
  * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifndef __XDG_MIME_INT_H__
diff --git a/gio/xdgmime/xdgmimemagic.c b/gio/xdgmime/xdgmimemagic.c
index dcee0fd59..98a1274c8 100644
--- a/gio/xdgmime/xdgmimemagic.c
+++ b/gio/xdgmime/xdgmimemagic.c
@@ -6,23 +6,7 @@
  * Copyright (C) 2003  Red Hat, Inc.
  * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
@@ -798,6 +782,11 @@ _xdg_mime_magic_read_magic_file (XdgMimeMagic *mime_magic,
 	  break;
 	case XDG_MIME_MAGIC_ERROR:
 	  state = _xdg_mime_magic_parse_error (magic_file);
+
+	  /* After a parse error we can only be at EOF or reset to starting a
+	   * new section. */
+	  assert (state == XDG_MIME_MAGIC_EOF || state == XDG_MIME_MAGIC_SECTION);
+
 	  break;
 	case XDG_MIME_MAGIC_EOF:
 	default:
diff --git a/gio/xdgmime/xdgmimemagic.h b/gio/xdgmime/xdgmimemagic.h
index eb06a81f8..81125c2a0 100644
--- a/gio/xdgmime/xdgmimemagic.h
+++ b/gio/xdgmime/xdgmimemagic.h
@@ -6,23 +6,7 @@
  * Copyright (C) 2003  Red Hat, Inc.
  * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
  *
- * 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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifndef __XDG_MIME_MAGIC_H__
diff --git a/gio/xdgmime/xdgmimeparent.c b/gio/xdgmime/xdgmimeparent.c
index 89b48fc16..e03a78f6c 100644
--- a/gio/xdgmime/xdgmimeparent.c
+++ b/gio/xdgmime/xdgmimeparent.c
@@ -6,23 +6,7 @@
  * Copyright (C) 2004  Red Hat, Inc.
  * Copyright (C) 2004  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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifdef HAVE_CONFIG_H
diff --git a/gio/xdgmime/xdgmimeparent.h b/gio/xdgmime/xdgmimeparent.h
index 29f43bc1f..b656e38cc 100644
--- a/gio/xdgmime/xdgmimeparent.h
+++ b/gio/xdgmime/xdgmimeparent.h
@@ -6,23 +6,7 @@
  * Copyright (C) 2004  Red Hat, Inc.
  * Copyright (C) 200  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 2.1 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.
+ * SPDX-License-Identifier: LGPL-2.1-or-later or AFL-2.0
  */
 
 #ifndef __XDG_MIME_PARENT_H__