osi-tools/Documentation/disk-formats.md

Adding "disk" formats to osi-mk

Create a file lib/mk/format-*.sh, and source that file from bin/osi-mk.

In that file:

• required: set formats+=('YOURFORMAT')

• required: set format_options['YOURFORMAT']= to a whitespace-separated list of the --conf=format.XXX= flags that your format takes.

• optional: define format_checkconf:YOURFORMAT() { … } to insert your own validation for --conf= flags.

• optional: define format_genfstab:YOURFORMAT() { … } to override the usual genfstab command.

• required: set format_is_block['YOURFORMAT']= to true or false, indicating whether osi-mk should pre-allocate a file for you (pointed at by $arg_file).

  • if format_is_block['YOURFORMAT']='true', then

    • required: define format_mkfs:YOURFORMAT() { … } which runs the appropriate mkfs on $arg_file.

    • required: define format_editfs:YOURFORMAT() { … } which applies any --conf=format.XXX= flags. If format.size is set, then you don't need to resize the file itself, osi-mk does that before/after calling format_editfs:YOURFORMAT, but you do need to run resize2fs or btrfs filesystem resize or whatever.

  • if format_is_block['YOURFORMAT']='false', then

    • required: set format_wants_tmpfs['YOURFORMAT'] to true or false, indicating whether $mount_dev should be set to a tmpfs (instead of $arg_file) and whether $mount_opt should be set to bind.

    • required: define format_before:YOURFORMAT() { … } that does any nescessary setup on $mount_dev/$mount_opt before mounting it to do the install.

    • required: define format_after:YOURFORMAT() { … } that does any nescessary transforms to get from $mount_dev to $arg_file.

    • required: set format_after_clamps_mtime['YOURFORMAT']= to true or false indicating whether your format_after:YOURFORMAT function clamps mtimes to SOURCE_DATE_EPOCH (true), or whether osi-mk should adjust all the mtimes before calling format_after:YOURFORMAT