[glib] Add G_FILE_ATTRIBUTE_FILESYSTEM_USED to get exact used space

[Matthias Clasen <matthiasc src gnome org>]

commit 00c00e2f3f3194202877e54a2429bd1a4f9c5526
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Jan 9 21:49:08 2012 -0500

    Add G_FILE_ATTRIBUTE_FILESYSTEM_USED to get exact used space
    
    This is implemented by with statfs_buffer.f_bavail (free blocks
    for unprivileged users) as a default way to retrieve real free space.
    Based on a patch by Marcus Carlson, bug 625751.

 docs/reference/gio/gio-sections.txt |    1 +
 gio/gfileattribute.c                |    1 +
 gio/gfileinfo.h                     |   11 +++++++++++
 gio/glocalfile.c                    |   19 +++++++++++++++++++
 4 files changed, 32 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/gio/gio-sections.txt b/docs/reference/gio/gio-sections.txt
index 62b233a..8c59f3b 100644
--- a/docs/reference/gio/gio-sections.txt
+++ b/docs/reference/gio/gio-sections.txt
@@ -295,6 +295,7 @@ G_FILE_ATTRIBUTE_THUMBNAILING_FAILED
 G_FILE_ATTRIBUTE_PREVIEW_ICON
 G_FILE_ATTRIBUTE_FILESYSTEM_SIZE
 G_FILE_ATTRIBUTE_FILESYSTEM_FREE
+G_FILE_ATTRIBUTE_FILESYSTEM_USED
 G_FILE_ATTRIBUTE_FILESYSTEM_TYPE
 G_FILE_ATTRIBUTE_FILESYSTEM_READONLY
 G_FILE_ATTRIBUTE_GVFS_BACKEND
diff --git a/gio/gfileattribute.c b/gio/gfileattribute.c
index 8e4b8bf..bca38cc 100644
--- a/gio/gfileattribute.c
+++ b/gio/gfileattribute.c
@@ -194,6 +194,7 @@
  * <row><entry>%G_FILE_ATTRIBUTE_PREVIEW_ICON</entry><entry>preview::icon</entry><entry>object (#GIcon)</entry></row>
  * <row><entry>%G_FILE_ATTRIBUTE_FILESYSTEM_SIZE</entry><entry>filesystem::size</entry><entry>uint64</entry></row>
  * <row><entry>%G_FILE_ATTRIBUTE_FILESYSTEM_FREE</entry><entry>filesystem::free</entry><entry>uint64</entry></row>
+ * <row><entry>%G_FILE_ATTRIBUTE_FILESYSTEM_USED</entry><entry>filesystem::used</entry><entry>uint64</entry></row>
  * <row><entry>%G_FILE_ATTRIBUTE_FILESYSTEM_TYPE</entry><entry>filesystem::type</entry><entry>string</entry></row>
  * <row><entry>%G_FILE_ATTRIBUTE_FILESYSTEM_READONLY</entry><entry>filesystem::readonly</entry><entry>boolean</entry></row>
  * <row><entry>%G_FILE_ATTRIBUTE_GVFS_BACKEND</entry><entry>gvfs::backend</entry><entry>string</entry></row>
diff --git a/gio/gfileinfo.h b/gio/gfileinfo.h
index 952dade..375a078 100644
--- a/gio/gfileinfo.h
+++ b/gio/gfileinfo.h
@@ -729,6 +729,17 @@ typedef struct _GFileInfoClass   GFileInfoClass;
 #define G_FILE_ATTRIBUTE_FILESYSTEM_FREE "filesystem::free"                       /* uint64 */
 
 /**
+ * G_FILE_ATTRIBUTE_FILESYSTEM_USED:
+ *
+ * A key in the "filesystem" namespace for getting the number of bytes of used on the
+ * file system. Corresponding #GFileAttributeType is
+ * %G_FILE_ATTRIBUTE_TYPE_UINT64.
+ *
+ * Since: 2.32
+ */
+#define G_FILE_ATTRIBUTE_FILESYSTEM_USED "filesystem::used"                       /* uint64 */
+
+/**
  * G_FILE_ATTRIBUTE_FILESYSTEM_TYPE:
  *
  * A key in the "filesystem" namespace for getting the file system's type.
diff --git a/gio/glocalfile.c b/gio/glocalfile.c
index 7c1b05b..cfd805a 100644
--- a/gio/glocalfile.c
+++ b/gio/glocalfile.c
@@ -993,6 +993,25 @@ g_local_file_query_filesystem_info (GFile         *file,
 #endif /* G_OS_WIN32 */
     }
 
+  if (!no_size &&
+      g_file_attribute_matcher_matches (attribute_matcher,
+                                        G_FILE_ATTRIBUTE_FILESYSTEM_USED))
+    {
+#ifdef G_OS_WIN32
+      gchar *localdir = g_path_get_dirname (local->filename);
+      wchar_t *wdirname = g_utf8_to_utf16 (localdir, -1, NULL, NULL, NULL);
+      ULARGE_INTEGER li_free;
+      ULARGE_INTEGER li_total;
+
+      g_free (localdir);
+      if (GetDiskFreeSpaceExW (wdirname, &li_free, &li_total, NULL))
+        g_file_info_set_attribute_uint64 (info, G_FILE_ATTRIBUTE_FILESYSTEM_USED,  (guint64)li_total.QuadPart - (guint64)li_free.QuadPart);
+      g_free (wdirname);
+#else
+      g_file_info_set_attribute_uint64 (info, G_FILE_ATTRIBUTE_FILESYSTEM_USED, block_size * (statfs_buffer.f_blocks - statfs_buffer.f_bfree));
+#endif /* G_OS_WIN32 */
+    }
+
 #ifndef G_OS_WIN32
 #ifdef USE_STATFS
 #if defined(HAVE_STRUCT_STATFS_F_FSTYPENAME)