[gnome-boxes] Add ISOExtractor class

[Christophe Fergeau <teuf src gnome org>]

commit f82ee12b9d5640e1b63d61285d657a9bf438feee
Author: Christophe Fergeau <cfergeau redhat com>
Date:   Fri May 25 17:42:03 2012 +0200

    Add ISOExtractor class
    
    It's used to mount an iso image and to read some content from it.
    Boxes will use it to get the extra drivers to copy to the winxp
    unattended install floppy.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=679752

 src/Makefile.am        |    1 +
 src/iso-extractor.vala |   57 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+), 0 deletions(-)
---
diff --git a/src/Makefile.am b/src/Makefile.am
index c702f99..f8b8cce 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -86,6 +86,7 @@ gnome_boxes_SOURCES =				\
 	fedora-installer.vala 			\
 	i-properties-provider.vala		\
 	installer-media.vala 			\
+	iso-extractor.vala			\
 	libvirt-machine.vala			\
 	machine.vala				\
 	main.vala				\
diff --git a/src/iso-extractor.vala b/src/iso-extractor.vala
new file mode 100644
index 0000000..6e9bb64
--- /dev/null
+++ b/src/iso-extractor.vala
@@ -0,0 +1,57 @@
+// This file is part of GNOME Boxes. License: LGPLv2+
+
+// Helper class to extract files from an ISO image
+private class Boxes.ISOExtractor: GLib.Object {
+    private string device_file;
+    private string mount_point;
+    private bool mounted;
+
+    public ISOExtractor (string iso_path) {
+        this.device_file = iso_path;
+    }
+
+    ~ISOExtractor () {
+        if (!mounted)
+            return;
+
+        debug ("Unmounting '%s'..", mount_point);
+        string[] argv = { "fusermount", "-u", mount_point };
+        exec.begin (argv, null);
+        debug ("Unmounted '%s'.", mount_point);
+    }
+
+    public async void mount_media (Cancellable? cancellable) throws GLib.Error {
+        if (mounted)
+            return;
+
+        string iso_name = File.new_for_path (device_file).get_basename ();
+
+        string temp_name = get_user_pkgcache (iso_name + "-XXXXXX");
+        string? mount_point = GLib.DirUtils.mkdtemp (temp_name);
+        if (mount_point == null)
+            throw (GLib.IOError) new GLib.Error (G_IO_ERROR, g_io_error_from_errno (errno), "Failed to create temporary mountpoint %s", temp_name);
+        this.mount_point = mount_point;
+
+        debug ("Mounting '%s' on '%s'..", device_file, mount_point);
+        // the -p option tells fuseiso to rmdir the mountpoint on unmount
+        string[] argv = { "fuseiso", "-p", device_file, mount_point };
+        yield exec (argv, cancellable);
+        debug ("'%s' now mounted on '%s'.", device_file, mount_point);
+
+        mounted = true;
+    }
+
+    public async GLib.FileEnumerator enumerate_children (string rel_path, Cancellable? cancellable) throws GLib.Error
+                                                         requires (mounted) {
+
+        string abs_src_path = Path.build_filename (mount_point, rel_path);
+        File dir = File.new_for_path (abs_src_path);
+
+        return yield dir.enumerate_children_async (FileAttribute.STANDARD_NAME, 0, GLib.Priority.DEFAULT, cancellable);
+    }
+
+    public string get_absolute_path (string relative_path) throws GLib.Error
+                                     requires (mounted) {
+        return Path.build_filename (mount_point, relative_path);
+    }
+}