[glib/wip/oholy/x-gvfs-notrash: 10/10] gfile: Add support for x-gvfs-notrash option to ignore mounts

[Philip Withnall <pwithnall src gnome org>]

commit ad1eb5b420bdc6543fb7c3b7928ec256d6c37a1d
Author: Ondrej Holy <oholy redhat com>
Date:   Tue Jun 23 08:36:26 2020 +0200

    gfile: Add support for x-gvfs-notrash option to ignore mounts
    
    Add support for x-gvfs-notrash mount option, which allows to disable
    trash functionality for certain mounts. This might be especially useful
    e.g. to prevent trash folder creation on enterprise shares, which are
    also accessed from Windows...
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1096200

 gio/gfile.c      |  4 +++-
 gio/glocalfile.c | 61 ++++++++++++++++++++++++++++++++++++++++++++------------
 2 files changed, 51 insertions(+), 14 deletions(-)
---
diff --git a/gio/gfile.c b/gio/gfile.c
index a2ded14ea..a8d12aa2c 100644
--- a/gio/gfile.c
+++ b/gio/gfile.c
@@ -4134,7 +4134,9 @@ g_file_delete_finish (GFile         *file,
  * Sends @file to the "Trashcan", if possible. This is similar to
  * deleting it, but the user can recover it before emptying the trashcan.
  * Not all file systems support trashing, so this call can return the
- * %G_IO_ERROR_NOT_SUPPORTED error.
+ * %G_IO_ERROR_NOT_SUPPORTED error. Since GLib 2.66, the `x-gvfs-notrash` unix
+ * mount option can be used to disable g_file_trash() support for certain
+ * mounts, the %G_IO_ERROR_NOT_SUPPORTED error will be returned in that case.
  *
  * If @cancellable is not %NULL, then the operation can be cancelled by
  * triggering the cancellable object from another thread. If the operation
diff --git a/gio/glocalfile.c b/gio/glocalfile.c
index a92c7b28b..74317f1e1 100644
--- a/gio/glocalfile.c
+++ b/gio/glocalfile.c
@@ -1815,6 +1815,52 @@ try_make_relative (const char *path,
   return g_strdup (path);
 }
 
+static gboolean
+ignore_trash_mount (GUnixMountEntry *mount)
+{
+  GUnixMountPoint *mount_point = NULL;
+  const gchar *mount_options;
+  gboolean retval = TRUE;
+
+  if (g_unix_mount_is_system_internal (mount))
+    return TRUE;
+
+  mount_options = g_unix_mount_get_options (mount);
+  if (mount_options == NULL)
+    {
+      mount_point = g_unix_mount_point_at (g_unix_mount_get_mount_path (mount),
+                                           NULL);
+      if (mount_point != NULL)
+        mount_options = g_unix_mount_point_get_options (mount_point);
+    }
+
+  if (mount_options == NULL ||
+      strstr (mount_options, "x-gvfs-notrash") == NULL)
+    retval = FALSE;
+
+  g_clear_pointer (&mount_point, g_unix_mount_point_free);
+
+  return retval;
+}
+
+static gboolean
+ignore_trash_path (const gchar *topdir)
+{
+  GUnixMountEntry *mount;
+  gboolean retval = TRUE;
+
+  mount = g_unix_mount_at (topdir, NULL);
+  if (mount == NULL)
+    goto out;
+
+  retval = ignore_trash_mount (mount);
+
+ out:
+  g_clear_pointer (&mount, g_unix_mount_free);
+
+  return retval;
+}
+
 gboolean
 _g_local_file_has_trash_dir (const char *dirname, dev_t dir_dev)
 {
@@ -1825,7 +1871,6 @@ _g_local_file_has_trash_dir (const char *dirname, dev_t dir_dev)
   char uid_str[32];
   GStatBuf global_stat, trash_stat;
   gboolean res;
-  GUnixMountEntry *mount;
 
   if (g_once_init_enter (&home_dev_set))
     {
@@ -1844,17 +1889,13 @@ _g_local_file_has_trash_dir (const char *dirname, dev_t dir_dev)
   if (topdir == NULL)
     return FALSE;
 
-  mount = g_unix_mount_at (topdir, NULL);
-  if (mount == NULL || g_unix_mount_is_system_internal (mount))
+  if (ignore_trash_path (topdir))
     {
-      g_clear_pointer (&mount, g_unix_mount_free);
       g_free (topdir);
 
       return FALSE;
     }
 
-  g_clear_pointer (&mount, g_unix_mount_free);
-
   globaldir = g_build_filename (topdir, ".Trash", NULL);
   if (g_lstat (globaldir, &global_stat) == 0 &&
       S_ISDIR (global_stat.st_mode) &&
@@ -2020,7 +2061,6 @@ g_local_file_trash (GFile         *file,
     {
       uid_t uid;
       char uid_str[32];
-      GUnixMountEntry *mount;
 
       uid = geteuid ();
       g_snprintf (uid_str, sizeof (uid_str), "%lu", (unsigned long)uid);
@@ -2034,20 +2074,15 @@ g_local_file_trash (GFile         *file,
          return FALSE;
        }
 
-      mount = g_unix_mount_at (topdir, NULL);
-      if (mount == NULL || g_unix_mount_is_system_internal (mount))
+      if (ignore_trash_path (topdir))
         {
           g_set_error (error, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
                        _("Trashing on system internal mounts is not supported"));
-
-          g_clear_pointer (&mount, g_unix_mount_free);
           g_free (topdir);
 
           return FALSE;
         }
 
-      g_clear_pointer (&mount, g_unix_mount_free);
-
       /* Try looking for global trash dir $topdir/.Trash/$uid */
       globaldir = g_build_filename (topdir, ".Trash", NULL);
       if (g_lstat (globaldir, &global_stat) == 0 &&