Re: [Libguestfs] [PATCH v6 2/7] daemon: Changing the way that we detect if a device contains partitions.
On Tue, May 01, 2018 at 03:53:59AM +0300, Mykola Ivanets wrote:
Instead of using part_to_dev to find such devices we open the
device's
directory under /sys/block/<device> and look for entries starting with
<device>, eg. /sys/block/sda/sda1.
+(* Look to see if device can directly contain filesystem
(RHBZ#590167).
+ * Partitioned devices cannot contain fileystem, so we will exclude such devices.
+ *)
Let's keep lines to < 80 characters.
+and is_not_partitioned_device device =
+ assert (String.is_prefix device "/dev/");
+ let device = String.sub device 5 (String.length device - 5) in
+ let dir = "/sys/block/" ^ device in
+
+ try
+ (* Open the device's directory under /sys/block/<device> and
+ * look for entries starting with <device>, eg. /sys/block/sda/sda1
+ *)
+ let parts = Array.to_list (Sys.readdir dir) in
+ let has_partition = List.exists (fun part -> String.is_prefix part device) parts
in
Also this line is >= 80 characters, but could easily be changed
so it's shorter.
+ not has_partition
+ with Sys_error (_) -> true
This is the real problem. What Sys_error is expected here? As far as
I can tell if anything throws Sys_error (or any other exception) here
then it's a real bug, so we shouldn't hide the error message. If
you're not expecting a particular Sys_error, then don't try to catch
anything.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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