Change output format of filefrag

[Kalpak Shah <kalpak@clusterfs.com>]

Hi,

I am adding FIEMAP support to filefrag and I noticed that current output
format of filefrag can be improved a lot. It is very difficult to add
information like lun, extent type, etc. to such a format.

$ filefrag  -v /tmp/abc 

Checking /tmp/abc
Filesystem type is: ef53
Filesystem cylinder groups is approximately 296
File is stored in extents format
Blocksize of file /tmp/abc is 1024
File size of /tmp/abc is 10485760 (10240 blocks)
First block: 4609
Last block: 26068
Discontinuity: Block 512 is at 8556 (was 5120)
Discontinuity: Block 517 is at 15729 (was 8560)
Discontinuity: Block 1173 is at 16633 (was 16384)
Discontinuity: Block 9117 is at 24945 (was 24576)
Discontinuity: Block 9125 is at 24954 (was 24952)
/tmp/abc: 6 extents found

I think an output format similar to that of xfs may be better. This is
easier for parsing as well. Like this:

$ filefrag -e {filename}

ext:    logical:   phys start..end kB:  kB :lun: flags
  0:   [0..151]: 288444888..288445039: 152 : 0 :
  1: [152..199]: XXXXXXXX..YYYYYYYYYY:  47 : 0 : hole
  2: [200..299]: MMMMMMMM..NNNNNNNNNN: 100 : 0 : unwritten, unknown

Please suggest if this is ok.

Thanks,
Kalpak.