| | 1 | //! *pxar* Implementation (proxmox file archive format) |
| | 2 | //! |
| | 3 | //! This code implements a slightly modified version of the *catar* |
| | 4 | //! format used in the [casync](https://github.com/systemd/casync) |
| | 5 | //! toolkit (we are not 100\% binary compatible). It is a file archive |
| | 6 | //! format defined by 'Lennart Poettering', specially defined for |
| | 7 | //! efficient deduplication. |
| | 8 | |
| | 9 | //! Every archive contains items in the following order: |
| | 10 | //! * `ENTRY` -- containing general stat() data and related bits |
| | 11 | //! * `USER` -- user name as text, if enabled |
| | 12 | //! * `GROUP` -- group name as text, if enabled |
| | 13 | //! * `XATTR` -- one extended attribute |
| | 14 | //! * ... -- more of these when there are multiple defined |
| | 15 | //! * `ACL_USER` -- one `USER ACL` entry |
| | 16 | //! * ... -- more of these when there are multiple defined |
| | 17 | //! * `ACL_GROUP` -- one `GROUP ACL` entry |
| | 18 | //! * ... -- more of these when there are multiple defined |
| | 19 | //! * `ACL_GROUP_OBJ` -- The `ACL_GROUP_OBJ` |
| | 20 | //! * `ACL_DEFAULT` -- The various default ACL fields if there's one defined |
| | 21 | //! * `ACL_DEFAULT_USER` -- one USER ACL entry |
| | 22 | //! * ... -- more of these when multiple are defined |
| | 23 | //! * `ACL_DEFAULT_GROUP` -- one GROUP ACL entry |
| | 24 | //! * ... -- more of these when multiple are defined |
| | 25 | //! * `FCAPS` -- file capability in Linux disk format |
| | 26 | //! * `QUOTA_PROJECT_ID` -- the ext4/xfs quota project ID |
| | 27 | //! * `PAYLOAD` -- file contents, if it is one |
| | 28 | //! * `SYMLINK` -- symlink target, if it is one |
| | 29 | //! * `DEVICE` -- device major/minor, if it is a block/char device |
| | 30 | //! |
| | 31 | //! If we are serializing a directory, then this is followed by: |
| | 32 | //! |
| | 33 | //! * `FILENAME` -- name of the first directory entry (strictly ordered!) |
| | 34 | //! * `<archive>` -- serialization of the first directory entry's metadata and contents, |
| | 35 | //! following the exact same archive format |
| | 36 | //! * `FILENAME` -- name of the second directory entry (strictly ordered!) |
| | 37 | //! * `<archive>` -- serialization of the second directory entry |
| | 38 | //! * ... |
| | 39 | //! * `GOODBYE` -- lookup table at the end of a list of directory entries |
| | 40 | |
| | 41 | //! |
| | 42 | //! The original format has no way to deal with hardlinks, so we |
| | 43 | //! extended the format by a special `HARDLINK` tag, which can replace |
| | 44 | //! an `ENTRY` tag. The `HARDLINK` tag contains an 64bit offset which |
| | 45 | //! points to the linked `ENTRY` inside the archive, followed by the |
| | 46 | //! full path name of that `ENTRY`. `HARDLINK`s may not have further data |
| | 47 | //! (user, group, acl, ...) because this is already defined by the |
| | 48 | //! linked `ENTRY`. |
| | 49 | |
| | 50 | pub(crate) mod create; |
| | 51 | pub(crate) mod dir_stack; |
| | 52 | pub(crate) mod extract; |
| | 53 | pub(crate) mod metadata; |
| | 54 | pub(crate) mod tools; |
| | 55 | |
| | 56 | mod flags; |
| | 57 | pub use flags::Flags; |
| | 58 | |
| | 59 | pub use create::{ |
| | 60 | create_archive, MetadataArchiveReader, PxarCreateOptions, PxarPrevRef, PxarWriters, |
| | 61 | }; |
| | 62 | pub use extract::{ |
| | 63 | create_tar, create_zip, extract_archive, extract_sub_dir, extract_sub_dir_seq, ErrorHandler, |
| | 64 | OverwriteFlags, PxarExtractContext, PxarExtractOptions, |
| | 65 | }; |
| | 66 | |
| | 67 | /// The format requires to build sorted directory lookup tables in |
| | 68 | /// memory, so we restrict the number of allowed entries to limit |
| | 69 | /// maximum memory usage. |
| | 70 | pub const ENCODER_MAX_ENTRIES: usize = 1024 * 1024; |
| | 71 | |
| | 72 | pub use tools::{format_multi_line_entry, format_single_line_entry}; |
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