readme.md

PyCPIO

A library for creating CPIO files in Python.

Currently, the library only supports the New ASCII format, and xz compression

This library is primary designed for use in ugrd to create CPIO archives for use in initramfs.

Usage

  -h, --help            show this help message and exit
  -d, --debug           enable debug mode (level 10)
  -dd, --trace          enable trace debug mode (level 5)
  -v, --version         print the version and exit
  --log-file LOG_FILE   set the path to the log file
  --log-level LOG_LEVEL
                        set the log level
  --log-time            enable log timestamps
  --no-log-color        disable log color
  -i INPUT, --input INPUT
                        input file
  -a APPEND, --append APPEND
                        append to archive
  --recursive RECURSIVE
                        append to archive recursively
  --relative RELATIVE   append to archive relative to this path
  --absolute            allow absolute paths
  --reproducible        Set mtime to 0, start inodes at 0
  --rm RM, --delete RM  delete from archive
  -n NAME, --name NAME  Name/path override for append
  -s SYMLINK, --symlink SYMLINK
                        create symlink
  -c CHARDEV, --chardev CHARDEV
                        create character device
  --major MAJOR         major number for character/block device
  --minor MINOR         minor number for character/block device
  -u UID, --set-owner UID
                        set UID on all files
  -g GID, --set-group GID
                        set GID on all files
  -m MODE, --set-mode MODE
                        set mode on all files
  -z COMPRESS, --compress COMPRESS
                        compression type
  -o OUTPUT, --output OUTPUT
                        output file
  -l, --list            list CPIO contents
  -p, --print           print CPIO contents

Structure

• pycpio.header.cpioheader: The class which represents a CPIO header
  • Can be initialized from args for header fields, or bytes representing a header
  • header types are defined in pycpio.header.headers (only the new ascii format is supported)
• pycpio.cpio.data: The class which represents a CPIO data block
  • Each CPIO object must have a header.
  • Currently the follwing subtypes are supported:
    • file : A regular file, or hardlink.
    • dir : A directory
    • symlink : A symbolic link
    • chardev : A character device
  • CPIO objects are collected in a pycpio.cpio.archive object
    • The archive handles duplication, inode generation, name normalization, and other collection related tasks
  • All CPIO object types can be initialized from args, bytes, or a file path