[RFC] e2fsprogs/mke2fs: add an option "-d root-directory"

[Robert Yang <liezhi.yang@windriver.com>]

Hello folks,

I'd like to add an "-d root-directory" option for mke2fs, which is used
for adding files from the "root-directory" to the filesystem after the
formatting, it is similar to genext2fs, but which only supports ext2 AFAIK.
it's usage example would be:

$ mke2fs -t extX -d <dir> <device>

I've done a few work on it, we can re-use the code from debugfs/debugfs.c,
here are the draft implementation thoughts:

Move a part of the code from debugfs/debugfs.c to misc/util.c, for example,
we will change the function do_write() in debugfs.c to:

void do_write(int argc, char *argv[])
{
	[snip];
	retval = do_write_internal();
         [snip];
}

The do_write_internal() will be defined in misc/util.c, then both debugfs.c
and mke2fs.c can use it. We will do the similar thing to do_mkdir(),
do_symlink() and so on.

My questions are:
1) Is the "-d root-directory" option acceptable ?
2) Is the implementation idea OK ?

Please feel free to give your comments, and I will send the patches later
if this is fine.

-- 
Thanks

Robert