[libvirt] [PATCH v3 4/4] logical: Display thin lv's found in a libvirt managed volume group

[John Ferlan]

On 02/02/2016 03:11 AM, Ján Tomko wrote:
> On Mon, Feb 01, 2016 at 03:29:53PM -0500, John Ferlan wrote:
>> Modify the regex for the 'devices' (a/k/a 'extents') from "(\\S+)"
>> (e.g., 1 or more) to "(\\S*)" (e.g., zero or more).
>>
>> Then for any "thin" lv's found, mark the volume as a sparse volume so
>> that the volume wipe algorithm doesn't work.
>>
>> Since a "thin" segtype has no devices, this will result in any "thin"
>> lv part of some thin-pool within a volume group used as a libvirt pool
>> to be displayed as a possible volume to use.
>>
> 
> A thin pool is another layer on top of some of the LVs in the VG.
> I think it deserves a separate pool type.
> 
>> NB:
>> Based on a proposal authored by Joe Harvell <joe.harvell at tekcomms.com>,
>> but with much intervening rework, the resulting patch is changed from
>> the original concept. About all that remains is changing the regex and
>> checking for NULL/empty field during parse.
>>
>> Signed-off-by: John Ferlan <jferlan at redhat.com>
>> ---
>>  src/storage/storage_backend_logical.c | 22 ++++++++++++++--------
>>  1 file changed, 14 insertions(+), 8 deletions(-)
> 
>> @@ -342,7 +348,7 @@ virStorageBackendLogicalFindLVs(virStoragePoolObjPtr pool,
>>       *    striped, so "," is not a suitable separator either (rhbz 727474).
>>       */
>>      const char *regexes[] = {
>> -       "^\\s*(\\S+)#(\\S*)#(\\S+)#(\\S+)#(\\S+)#([0-9]+)#(\\S+)#([0-9]+)#([0-9]+)#(\\S+)#?\\s*$"
>> +       "^\\s*(\\S+)#(\\S*)#(\\S+)#(\\S*)#(\\S+)#([0-9]+)#(\\S+)#([0-9]+)#([0-9]+)#(\\S+)#?\\s*$"
> 
> This regex and changes to it would be much more readable split into
> multiple lines, like VIR_LOG_REGEX.
> 

OK - so if I create a 5th patch with something like, is that what you'd
like to see:

+#define VIR_STORAGE_VOL_LOGICAL_PREFIX_REGEX "^\\s*"
+#define VIR_STORAGE_VOL_LOGICAL_LV_NAME_REGEX "(\\S+)#"
+#define VIR_STORAGE_VOL_LOGICAL_ORIGIN_REGEX "(\\S*)#"
+#define VIR_STORAGE_VOL_LOGICAL_UUID_REGEX "(\\S+)#"
+#define VIR_STORAGE_VOL_LOGICAL_DEVICES_REGEX "(\\S*)#"
+#define VIR_STORAGE_VOL_LOGICAL_SEGTYPE_REGEX "(\\S+)#"
+#define VIR_STORAGE_VOL_LOGICAL_STRIPES_REGEX "([0-9]+)#"
+#define VIR_STORAGE_VOL_LOGICAL_SEG_SIZE_REGEX "(\\S+)#"
+#define VIR_STORAGE_VOL_LOGICAL_VG_EXTENT_SIZE_REGEX "([0-9]+)#"
+#define VIR_STORAGE_VOL_LOGICAL_SIZE_REGEX "([0-9]+)#"
+#define VIR_STORAGE_VOL_LOGICAL_LV_ATTR_REGEX "(\\S+)#"
+#define VIR_STORAGE_VOL_LOGICAL_SUFFIX_REGEX "?\\s*$"
+
+#define VIR_STORAGE_VOL_LOGICAL_REGEX_COUNT 10
+#define VIR_STORAGE_VOL_LOGICAL_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_PREFIX_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_LV_NAME_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_ORIGIN_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_UUID_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_DEVICES_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_SEGTYPE_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_STRIPES_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_SEG_SIZE_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_VG_EXTENT_SIZE_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_SIZE_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_LV_ATTR_REGEX \
+           VIR_STORAGE_VOL_LOGICAL_SUFFIX_REGEX
+

and

     const char *regexes[] = {
-
"^\\s*(\\S+)#(\\S*)#(\\S+)#(\\S*)#(\\S+)#([0-9]+)#(\\S+)#([0-9]+)#([0-9]+)#(\\S+)#?\\s*$"
+        VIR_STORAGE_VOL_LOGICAL_REGEX
     };
     int vars[] = {
-        10
+        VIR_STORAGE_VOL_LOGICAL_REGEX_COUNT
     };