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...
(left over from when the unified read/write structure was copied
to form separate read and write structures) and eliminate the
pointless initialization of a couple of the unused fields.
the number of bytes read is actually not important as long as we have at
least what we ask for. Illustrate its benefits by using it throughout
the ZIP support code, except for the few cases where it doesn't apply.
Approved by: kientzle
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.
implementation, and mark it as deprecated. It will be removed entirely
in libarchive 3.0 (in FreeBSD 8.0?) but there's no reason for anyone to
use it instead of archive_read_data.
Approved by: kientzle
discards it, for use when the compression layer code doesn't know how to
skip data (e.g., everything other than the "none" compressor). This makes
format level code simpler because that code can now assume that the
compression layer always knows how to skip and will always skip exactly
the requested number of bytes.
Discussed with: kientzle (3 months ago)
* 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.
Fallout from changing the skip API to use off_t instead of size_t: Print
the skip length using %jd and cast to (intmax_t) instead of %d / (int),
and if ARCHIVE_API_VERSION >= 2, allow the client skipper to be called
for requests longer than SSIZE_MAX. [2]
Approved by: kientzle
Pointy hats to: kientzle [1], cperciva [2]
MFC after: 3 days
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. ;-)
* Expose functions for setting the "skip file" dev/ino information
* Expose functions for setting/querying the block size on reads
* Correctly propagate errors out of archive_read_close/archive_write_close
* Update manpage with information about new functions
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.
routine fails or the first read fails), invoke the client close
routine immediately so the client can clean up. Also, don't store the
client pointers in this case, so that the client close routine can't
accidentally get called more than once.
A minor style fix to archive_read_open_fd.c while I'm here.
PR: 86453
Thanks to: Andrew Turner for reporting this and suggesting a fix.
"HEADER" unless the open is successful. Instead, leave the state as
"NEW." In particular, if archive_read_open() fails, a subsequent call
to archive_read_next_header() will now cause an explicit assertion
failure instead of a silent segmentation fault.
This may need a little more work to fully realize the intention: If
archive_read_open() fails, you should be able to call it again on the
same archive handle to open a different archive (or the same archive
using a different mechanism).
compiling on IRIX and Solaris. Remove the "archive_check_magic" macro
that existed only to provide __func__ to the underlying __archive_check_magic
function.
Thanks to: Darin Broady
MFC after: 14 days
* 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.
and close it) and "finish" (destroy the object) functions. For backwards
compat and simplicity, have "finish" invoke "close" transparently if needed.
This allows clients to close the archive and check end-of-operation
statistics before destroying the object.
push extract data down into archive_read_extract.c and out
of the library-global archive_private.h; push dir-specific
mode/time fixup down into dir restore function; now that the
fixup list is file-local, I can use somewhat more natural
naming.
Oh, yeah, update a bunch of comments to match current reality.
* 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.
* 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
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.
* 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
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.
