archivegen

README

archivegen is a tool to generate tar or cpio archives using a tmpfiles-like syntax.

The tool can be used to make initramfs or container images with tools like buildah.

Usage

Configuration can be read from stdin or from commandline arguments. -print can be used to inspect the resolved archive including ELF dependencies, recursive entries, etc.

Archives created from -print output results in the same archive.

Configuration file format

The configuration format is a simple line per entry with arguments separated by whitespace. examples

Types

Types suffixed with r are relative to -rootfs except L. LA can be used for absolute paths with ELFs, runpath/rpath $ORIGIN is also absolute when using LA. Arguments can be omitted with -.

* required

$ Variable, can be defined or overridden with -X from commandline

# $ *name value
$ a foo
# variables can be used to define variables
$ b bar
$ c $a$b
d $c

d Directory

# d *dst mode uid gid
# all non-existent diretories below are created with the same permissions
d a/b/c 0700 1 1

l Symlink

# l *src *dst mode uid gid
# source and destination are reversed
# usr/bin/sh is a symlink to busybox
l busybox usr/bin/sh

f, fr, a, ar File/Auto

# f *src dst mode uid gid
f /a/b/c/file foo/bar/baz

# destination is the source when omitted
f /a/b/c/file

# files prefixed with ? are omitted if they don't exist
?fr /optional

R, Rr Recursive

# R *src dst uid gid
# destination is the source when not specified
R a/b/c

# when destination is omitted, source is stripped from destination
R dir -

# source path is stripped from destination when specified
R a/b/c foo
# a/b/c/file -> foo/file

r, rr Regex

# r *src dst uid gid
# all matches are prefixed with dst
r /a/.*/c dst
# /a/b/c -> dst/a/b/c
r /a/.*/c -
# /a/b/c -> a/b/c

c, cl, b64 Create

# c *dst mode uid gid data
c file - - - contents
# trailing newline is omitted from argument
cl file - - - contents
# binary data can added as base64
b64 file - - - Y29udGVudHMK
# argument can be a heredoc, variables are expanded inside heredoc
$ variable data
c file - - - <<!
$variable
!

L, LA, rL, i ELF

# L *src dst mode uid gid
# src and all dependencies are read from rootfs
# -rootfs /foo -> /foo/usr/bin/bash
L /usr/bin/bash
# using LA, src and dependencies from rpath/runpath containing $ORIGIN are not prefixed with rootfs

# rL *src - - uid gid
# dst and mode are ignored
rL /usr/lib/httpd/modules/.so$

# search library paths
i libnss_files.so.2

Repeating entries

Entry source can be repeated using braces (nesting not supported), only symlink destination can be repeated.

# destination is the source when not specified
f file{1,2}

# destination is the source file joined to the argument
f a/b/c/file{1,2} foo
# foo/file1
# foo/file2

# variables can be used in repeating arguments
$ bin sh,cat,ls
l busybox usr/bin/{$bin}

# arguments can span multiple lines
l ../{
	foo
	bar
} baz
# baz/foo -> ../foo

Masks

Masks can be used to rewrite, modify or exclude entries from archives using regular expressions. https://golang.org/s/re2syntax

mm Mode

# mm *idx *regexp mode uid gid
# mask all files to be owned by root
mm - . - 0 0
# index can be omitted or used to override current masks
mm 0 . - 100 100

mr Rewrite

# mr *idx *regexp *dst
mr - a/b/c foo
d a/b/c/bar
# -> foo/bar

mi, mI Ignore

# mi *idx *regexp
# a
# ├── b
# │   ├── file1
# │   └── file2
# └── file3

# ignore b
mi - foo/b
# ignore everything except b 
mI - foo/b
# recursively add a to foo
R a foo

mc Clear

# mc idx
# clear all masks
mc
# clear the last mask
mc -
# clear the last n masks
mc -2