Description of problem:
When there are multiple scsi_id entries to choose from, and there often are, lsscsi stops scanning at the first one that matches the device, unfortunately the order of scsi id entries in /dev/disk/by-id directory are not guaranteed to be consistently ordered by prefix type so, in one case scsi-3<wwid> is output and for another scsi-0<id> is output although in the 2nd case a scsi-3<wwid> is present.  Order is unsorted directory order based (see ls -lUo output)

Output should be consistent and choose best identifier option available.


Version-Release number of selected component (if applicable):
0.31 latest upstream and shipped

How reproducible:
100%

Steps to Reproduce:
1. lsscsi --scsi_id
2.
3.

Actual results:
# lsscsi --scsi_id
[0:0:0:0]    storage HP       P410i            6.60  -          -
[0:1:0:0]    disk    HP       LOGICAL VOLUME   6.60  /dev/sda   SHP_LOGICAL_VOLUME_50014380145A2900
[0:1:0:1]    disk    HP       LOGICAL VOLUME   6.60  /dev/sdb   0HP_LOGICAL_VOLUME_01000000
[1:0:0:0]    cd/dvd  hp       DVD A  DS8A8SH   KHE4  /dev/sr0   -

so first device has a 'S' prefix and 2nd '0' type id (using vendor binary id in page 83), but both devices have '3' NAA wwid, 'S' and '0' scsi identifiers available to choose from



Expected results:

# ./lsscsi.dbg --scsi_id
[0:0:0:0]    storage HP       P410i            6.60  -          -
[0:1:0:0]    disk    HP       LOGICAL VOLUME   6.60  /dev/sda   3600508b1001cf6d83cad2f9741e23e51
[0:1:0:1]    disk    HP       LOGICAL VOLUME   6.60  /dev/sdb   3600508b1001c033030ea6dada3776da9
[1:0:0:0]    cd/dvd  hp       DVD A  DS8A8SH   KHE4  /dev/sr0   -




Additional info:

# ls -lUo /dev/disk/by-id | egrep "sda|sdb" | egrep -v "sda[1-9]|sdb[1-9]"
lrwxrwxrwx. 1 root  9 May 18 18:07 scsi-SHP_LOGICAL_VOLUME_50014380145A2900 -> ../../sda << first for sda
lrwxrwxrwx. 1 root  9 May 18 18:07 scsi-0HP_LOGICAL_VOLUME_00000000 -> ../../sda
lrwxrwxrwx. 1 root  9 May 18 18:07 scsi-0HP_LOGICAL_VOLUME_01000000 -> ../../sdb         << first for sdb
lrwxrwxrwx. 1 root  9 May 18 18:07 wwn-0x600508b1001c033030ea6dada3776da9 -> ../../sdb
lrwxrwxrwx. 1 root  9 May 18 18:07 scsi-3600508b1001c033030ea6dada3776da9 -> ../../sdb   << "best" sdb choice
lrwxrwxrwx. 1 root  9 May 18 18:07 wwn-0x600508b1001cf6d83cad2f9741e23e51 -> ../../sda   
lrwxrwxrwx. 1 root  9 May 18 18:07 scsi-3600508b1001cf6d83cad2f9741e23e51 -> ../../sda   << "best" sda choice


Instead of stopping at first match, process the directory for "best" match.  For example, an 'S' identifier is less likely to be world wide unique than a '3' (prefix) wwid.

One order, might be (with '3' being 'best' or most desirable to '0' being least desirable.

    '3' for NAA based (identification record within scsi INQUIRY page 0x83)
    '2' for EUI-64 based (identification record within scsi INQUIRY page 0x83)
    '8' for SCSI name string from scsi INQUIRY page 0x83
    'S' for string based (serial number from scsi INQUIRY page 0x80)
    '1' for T10 Vendor id based (identification record within scsi INQUIRY page 0x83)
    '0' for Vendor specific (identification record within scsi INQUIRY page 0x83)

From pg83:
		      Table 466 - Designator Type field
                      Code	Description					Reference
		      0h        Vendor Specific				        7.7.3.3
                      1h        T10 Vendor ID based                             7.7.3.4
                      2h        EUI-64 based                                    7.7.3.5
                      3h        NAA                                             7.7.3.6
                      4h        Relative target port identifier                 7.7.3.7
                      5h        Target port group                               7.7.3.8
                      6h        Logical unit group                              7.7.3.9
                      7h        MD5 logical unit identifier                     7.7.3.10
                      8h        SCSI name string                                7.7.3.11
                      9h-Fh     <Reserved>



The "expected" output is from code that added an order to lookup_dev():

        scsi_id = lookup_dev(dev_disk_byid_dir, "scsi-", "328S10", dev_node);

Then code captures first of the best prefix type it can find within the by-id directory by scanning all entries.  This then generates consistent output regardless of order within the directory.