increases performance when extracting a single entry from a large
uncompressed archive, especially on slow devices such as USB hard
drives.
Requires a number of changes:
* New archive_read_open2() supports a 'skip' client function
* Old archive_read_open() is implemented as a wrapper now, to
continue supporting the old API/ABI.
* _read_open_fd and _read_open_file sprout new 'skip' functions.
* compression layer gets a new 'skip' operation.
* compression_none passes skip requests through to client.
* compression_{gzip,bzip2,compress} simply ignore skip requests.
Thanks to: Benjamin Lutz, who designed and implemented the whole thing.
I'm just committing it. ;-)
TODO: Need to update the documentation a little bit.
occurred with large read-ahead requests. This only affected
formats that incorrectly make large requests (ZIP did this until
recently) or with block sizes over 32k.
try to set ACLs even if fflag restore fails, first cut at reading
Solaris tar ACLs
Code improvement: merge gnu tar read support into main tar reader;
this eliminates a lot of duplicate code and generalizes the tar
reader to handle formats with GNU-like extensions.
Style: Makefile cleanup, eliminate 'dmalloc' references, remove 'tartype'
from archive_entry (this makes archive_entry more format-agnostic)
Thanks to: David Magda for providing Solaris tar test files
with 'star' ACL handling, though there's still a
bit more work needed in this area.
Added 'write_open_fd' and 'read_open_fd' to simplify, e.g.,
tar's u and r modes. Eliminated old 'write_open_file_position'
as a bad idea. (It required closing/reopening files to
do updates, which led to unpleasant implications.)
Various other minor fixes, API tweaks, etc.
Portability: Thanks to Juergen Lock, libarchive now compiles cleanly
on Linux. Along the way, I cleaned up a lot of error return codes and
reorganized some code to simplify conditional compilation of certain
sections.
Bug fixes:
* pax format now actually stores filenames that are 101-154
characters long.
* pax format now allows newline characters in extended attributes
(this fixes a long-standing bug in ACL handling)
* mtime/atime are now restored for directories
* directory list is now sorted prior to fix-up to permit
correct restore of non-writable dir heirarchies
What it is:
A library for reading and writing various streaming archive
formats, especially tar and cpio. Being a library, it should
be easy to incorporate into pkg_* tools, sysinstall, and any
other place that needs to read or write such archives.
Features:
* Full automatic detection of both compression and archive format.
* Extensible internal architecture to make it easy to add new formats.
* Support for "pax interchange format," a new POSIX-standard tar format
that eliminates essentially all of the restrictions of historic formats.
* BSD license
Thanks to: jkh for pushing me to start this work, gordon for
encouraging me to commit it, bde for answering endless style
questions, and many others for feedback and encouragement.
Status: Pretty good overall, though there are still a few rough edges and
the library could always use more testing. Feedback eagerly solicited.
