This is an attempt to eliminate a lot of redundant
code from the read ("decompression") filters by
changing them to juggle arbitrary-sized blocks
and consolidate reblocking code at a single point
in archive_read.c.
Along the way, I've changed the internal read/consume
API used by the format handlers to a slightly
different style originally suggested by des@. It
does seem to simplify a lot of common cases.
The most dramatic change is, of course, to
archive_read_support_compression_none(), which
has just evaporated into a no-op as the blocking
code this used to hold has all been moved up
a level.
There's at least one more big round of refactoring
yet to come before the individual filters are as
straightforward as I think they should be...
that I've been working on but put off committing until after the
RELENG_7 branch, including:
* New manpages: cpio.5 mtree.5
* New archive_entry_strmode()
* New archive_entry_link_resolver()
* New read support: mtree format
* Internal API change: read format auction only runs once
* Running the auction only once allowed simplifying a lot of bid logic.
* Cpio robustness: search for next header after a sync error
* Support device nodes on ISO9660 images
* Eliminate a lot of unnecessary copies for uncompressed archives
* Corrected handling of new GNU --sparse --posix formats
* Correctly handle a zero-byte write to a compressed archive
* Fixed memory leaks
Many of these improvements were motivated by the upcoming bsdcpio
front-end.
There have also been extensive improvements to the libarchive_test
test harness, which I'll commit separately.
* "compression_program" support uses an external program
* Portability: no longer uses "struct stat" as a primary
data interchange structure internally
* Part of the above: refactor archive_entry to separate
out copy_stat() and stat() functions
* More complete tests for archive_entry
* Finish archive_entry_clone()
* Isolate major()/minor()/makedev() in archive_entry; remove
these from everywhere else.
* Bug fix: properly handle decompression look-ahead at end-of-data
* Bug fixes to 'ar' support
* Fix memory leak in ZIP reader
* Portability: better timegm() emulation in iso9660 reader
* New write_disk flags to suppress auto dir creation and not
overwrite newer files (for future cpio front-end)
* Simplify trailing-'/' fixup when writing tar and pax
* Test enhancements: fix various compiler warnings, improve
portability, add lots of new tests.
* Documentation: document new functions, first draft of
libarchive_internals.3
MFC after: 14 days
Thanks to: Joerg Sonnenberger (compression_program)
Thanks to: Kai Wang (ar)
Thanks to: Colin Percival (many small fixes)
Thanks to: Many others who sent me various patches and problem reports.
* libarchive_test program exercises many of the core features
* Refactored old "read_extract" into new "archive_write_disk", which
uses archive_write methods to put entries onto disk. In particular,
you can now use archive_write_disk to create objects on disk
without having an archive available.
* Pushed some security checks from bsdtar down into libarchive, where
they can be better optimized.
* Rearchitected the logic for creating objects on disk to reduce
the number of system calls. Several common cases now use a
minimum number of system calls.
* Virtualized some internal interfaces to provide a clearer separation
of read and write handling and make it simpler to override key
methods.
* New "empty" format reader.
* Corrected return types (this ABI breakage required the "2.0" version bump)
* Many bug fixes.
a vanilla 2-clause BSD license, but somehow some confusing
extra verbage get copied from somewhere.
Also, update the copyright dates to 2007 for all of the files.
Prompted by: several questions about what those extra words really mean
* Actually use the HAVE_<header>_H macros to conditionally include
system headers. They've been defined for a long time, but only
used in a few places. Now they're used pretty consistently
throughout.
* Fill in a lot of missing casts for conversions from void*.
Although Standard C doesn't require this, some people have been
trying to use C++ compilers with this code, and they do require it.
Bit-for-bit, the compiled object files are identical, except for
one assert() whose line number changed, so I'm pretty confident I
didn't break anything. ;-)
This commit implements storing/reading POSIX.1e-style extended
attribute information in "pax" format archives. An outline of the
storage format is in the tar.5 manpage. The archive_read_extract()
function has code to restore those archives to disk for Linux; FreeBSD
implementation is forthcoming.
Many thanks to Jaakko Heinonen for finding flaws in earlier
proposals and doing the bulk of the coding in this work.
* Handles entries with compressed size >2GB (signed/unsigned cleanup)
* Handles entries with compressed size >4GB ("ZIP64" extension)
* Handles Unix extensions (ctime, atime, mtime, mode, uid, etc)
* Format-specific "skip data" override allows ZIP reader to skip
entries without decompressing them, which makes "tar -t"
a lot faster.
* Handles "length-at-end" entries generated by, e.g., "zip -r - foo"
Many thanks to: Dan Nelson, who contributed the code and test files for
the first three items above and suggested the fourth.
simple errx() function.
Improve behavior when bzlib/zlib are missing by detecting and
issuing an error message on attempts to read gzip/bzip2 compressed
archives.
* New read_data_block is both sparse-file aware and uses zero-copy semantics
* Push read_data_block down into specific formats (opens door to
various encoded entry bodies, such as zip or gtar -S)
* Reimplement read_data, read_data_skip, read_data_into_fd in terms
of new read_data_block.
* Update documentation
It's unfortunate that I couldn't just call the new interface
archive_read_data, but didn't want to upset the API that much.
* little-endian old-style binary cpio archives
* big-endian old-style binary cpio archives
* SVR4 portable archives without CRC
* SVR4 portable archives with CRC
Note that I don't yet verify the CRC for the last one, and I'm
not quite certain I'm correctly parsing device numbers.
* Re-use a single buffer for shar output formatting rather
than hammering the heap. (archive_write_set_format_shar.c)
* Fix a handful of minor memory leaks and clean up some of the
memory-management code.
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
* Disabled shared-library building, as some API breakage is
still likely. (I didn't realize it was turned on by default.) If
you have an existing /usr/lib/libarchive.so.2, I recommend deleting it.
* Pax interchange format now correctly stores and reads UTF8
for extended attributes. In particular, pax format can portably
handle arbitrarily long pathnames containing arbitrary characters.
* Library compiles cleanly at -O2, -O3, and WARNS=6 on all
FreeBSD-CURRENT platforms.
* Minor portability improvements inspired by Juergen Lock
and Greg Lewis. (Less reliance on stdint.h, isolating of
various portability-challenged constructs.)
* archive_entry transparently converts multi-byte <-> wide character
strings, allowing clients and format handlers to deal with either
one, as appropriate.
* Support for reading 'L' and 'K' entries in standard tar archives
for star compatibility.
* Recognize (but don't yet handle) ACL entries from Solaris tar.
* Pushed format-specific data for format readers down into
format-specific storage and out of library-global storage. This
should make it easier to maintain individual formats without mucking
with the core library management.
* Documentation updates to track the above changes.
* Updates to tar.5 to correct a few mistakes and add some additional
information about GNU tar and Solaris tar formats.
Notes:
* The basic 'tar' reader is getting more general; there's not much
point in keeping the 'gnutar' reader separate. Merging the two
would lose a bunch of duplicate code.
* The libc ACL support is looking increasingly inadequate for my needs
here. I might need to assemble some fairly significant code for
parsing and building ACLs. <sigh>
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
This doesn't yet address the issue of selective restore
of hardlinked files. With cpio format, it's possible to correctly
restore any linked file; the API doesn't yet fully support this.
(There's no way for the library to inform a client whether or not
there's a file body associated with this entry. The assumption
right now is that "hardlink" entries have no file body.)
While I'm here, fix a bug in reading filenames from
cpio files. (Copy should count the length of the name,
not the number of bytes available for input.)
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.
