tests: limit autotest-functionname generation to sane characters
Some (older) versions of bash seem to be allergic to a method named
"aptautotest_grep_^apt" (note the caret). Unlikely that we are going to
write autotests for such commands so we could just skip those, but lets
instead just use "normal" characters in the names and strip the rest as
we already did with the (arguable more common) '-'.
support '-' and no parameter for stdin in apt-helper cat-file
This way it works more similar to the compressor binaries, which we
can relief in this way from their job in the test framework avoiding the
need of adding e.g. liblz4-tool to the test dependencies.
Downloading and storing are two different operations were different
compression types can be preferred. For downloading we provide the
choice via Acquire::CompressionTypes::Order as there is a choice to
be made between download size and speed – and limited by whats available
in the repository.
Storage on the other hand has all compressions currently supported by
apt available and to reduce runtime of tools accessing these files the
compression type should be a low-cost format in terms of decompression.
apt traditionally stores its indexes uncompressed on disk, but has
options to keep them compressed. Now that apt downloads additional files
we also deal with files which simply can't be stored uncompressed as
they are just too big (like Contents for apt-file). Traditionally they
are downloaded in a low-cost format (gz) as repositories do not provide
other formats, but there might be even lower-cost formats and for
download we could introduce higher-cost in the repositories.
Downloading an entire index potentially requires recompression to
another format, so an update takes potentially longer – but big files
are usually updated via pdiffs which has to de- and re-compress anyhow
and does it on the fly anyhow, so there is no extra time needed and in
general it seems to be benefitial to invest the time in update to save
time later on file access.
allow pdiff bootstrap from all supported compressors
There is no reason to enforce that the file we start the bootstrap with
is compressed with a compressor which is available online. This allows
us to change the on-disk format as well as deals with repositories
adding/removing support for a specific compressor.
ensure compression cleanup even without lists-cleanup
If we store files compressed in lists/ and the file switched compression
formats we happened to retain the "old" format, but by default the
cleanup process catched this oversight and removed the file.
[The initial situation described doesn't arise as we store no files by
default compressed and even with apt-file configuring Contents files, we
don't really have that problem as there is just .gz files for those.]
We solve this by just removing any uncompressed as well as compressed
(we support) file just before we move the 'new' version of the file in.
use one 'store' method to rule all (de)compressors
Adding a new compressor method meant adding a new method as well – even
if that boilt down to just linking to our generalized decompressor with
a new name. That is unneeded busywork if we can instead just call the
generalized decompressor and let it figure out which compressor to use
based on the filenames rather than by program name.
For compatibility we ship still 'gzip', 'bzip2' and co, but they are
just links to our "new" 'store' method.
include all compressed Packages/Sources files in Release file
Having a hardcoded list of compression types here doesn't really provide
us with anything beside added complexity each time someone adds a new
compression type. That we don't need to be that specific is evident by
Contents and Translation-* matchers which are a lot more generic and
didn't generate problems anyhow.
AvailableDescriptionLanguages: Use one string for all iterations
Do not create strings within the loop, that creates one string
per language and does more work than needed. Instead, reserve
enough space at the beginning and assign the prefix, and then
resize and append inside the loop.
Also call exists with the string itself instead of the c_str(),
this means that the lookup uses the size information in the
string now and does not have to call strlen() on it.
pkgCacheGenerator::StoreString: Get rid of std::string
Instead of storing a string -> map_stringitem_t mapping, create
our own data type that can point to either a normal string or
a string inside the cache.
This avoids the creation of any string and improves performance
slightly (about 4%).
pkgCacheGenerator::StoreString: Move the string into the map
Moving the string is likely faster than copying it. We could probably
avoid strings alltogether in the future using some more crazy code,
but I have not looked at that yet.
The class APT::StringView implements a drop-in replacement
for a subset of C++17 std::string_view() features. It will
be dropped at a later point and may not be used in public
interfaces.
acquire: Allow parallelizing methods without hosts
The maximum parallelization soft limit is the number of CPU
cores * 2 on systems defining _SC_NPROCESSORS_ONLN. The hard
limit in all cases is Acquire::QueueHost::Limit.
Helmut Grohne [Sun, 3 Jan 2016 14:10:05 +0000 (15:10 +0100)]
Allow building without libgtest-dev under <nocheck> build profile
I'd like to avoid pulling libgtest-dev into the bootstrap set.
Fortunately, libgtest-dev is only used for testing apt and apt
correctly implements DEB_BUILD_OPTIONS=nocheck now. So this
bug is about getting rid of the Build-Depends.
Simply removing it (by adding a build profile) is not sufficient
however as configure fails hard, so an additional bit is necessary
to cover for that.
Michael Vogt [Sat, 2 Jan 2016 21:08:30 +0000 (22:08 +0100)]
Add new APT::Keep-Downloaded-Packages option
This option controls if downloaded packages should be kept after
a successful install or if they should be deleted. The default
for "apt-get" is that they are kept (just like before).
However the default for "apt" is that they get deleted.
Michael Vogt [Sat, 2 Jan 2016 20:18:47 +0000 (21:18 +0100)]
Add bash-completion support for the "apt" command
The apt bash-completion support was submited to the bash-completion
package as a patch in May 2014. It is still not included to this
date and because it is an important feature for many users it is
now part of apt until the bash-completion package is mantained
more actively again.
Note that the "Relaces" line is only required for Ubuntu it will
have no effect on Debian.
Michael Vogt [Sat, 2 Jan 2016 20:24:47 +0000 (21:24 +0100)]
Add support for APT::Periodic::CleanInterval
In order to allow regular cleaning of the downloaded deb archives
the new option APT::Periodic::CleanInterval is added. It will run
"apt-get clean" in the given time interval.
properly parse comments in apt_preferences and deb822-style sources
apt_preferences and deb822-style sources used the specialized class
pkgUserTagSection to deal with comments before/after a given stanza, but
it couldn't deal with comments in the stanza at all.
codesearch suggests that nobody else does and a vastely superior way of
working with potentially commented files is implemented now, so we can
officially discourage the use of the old incomplete hack class.
Now (55153bf94ff28a23318e79aa48242244c4d82b3c) that pkgTagFile can be
told to deal with all sorts of comments we can use this mode to parse
dsc (as by catch) and debian/control files properly even in the wake of
multiline fields spliced with comments like Build-Depends.
APT usually deals with perfectly formatted files generated automatically
be other programs – and as it has to parse multiple MBs of such files it
tries to be fast rather than forgiving.
This was always a problem if we reused this parser for files with a
deb822 syntax which are mostly written by hand however, like
apt_preferences or the deb822-style sources as these can include stray
newlines and more importantly comments all over the place.
As a stopgap we had pkgUserTagSection which deals at least with comments
before and after a given stanza, but comments in between weren't really
supported and now that we support parsing debian/control for e.g.
build-dep we face the full comment problem e.g. with comments inbetween
multi-line fields (like Build-Depends).
We can't easily deal with this on the pkgTagSection level as the interface
gives access to 'raw' char-pointers for performance reasons so we would
need to optionally add a buffer here on which we could remove comments
to hand out pointers into this buffer instead. The interface is quite
large already and supports writing stanzas as well, which does not
support comments at all either. So while in future it might make sense
to have a parser setup which deals with and keeps comments in this
commit we opt for the simpler solution for now: We officially declare
that pkgTagSection does not support comments and instead expect the
caller to deal with them, which in our case is pkgTagFile:
pkgTagFile is extended with an additional mode which can deal with
comments by dropping them from the buffer which will later form the
input of pkgTagSection. The actual implementation is slightly more
complex than this sentence suggests at first on one hand to have good
performance and on the other to allow jumping directly to stanzas with
offsets collected in a previous run (like our cache generation does it
for example).
BufferedFileFdPrivate: Make InternalFlush() save against errors
Previously, if flush errored inside the loop, data could have
already been written to the wrapped descriptor without having
been removed from the buffer.
Also try to work around EINTR here. A better solution might be
to have the individual privates detect an interrupt and return
0 in such a case, instead of relying on errno being untouched
in between the syscall and the return from InternalWrite.
A default of -9 is too much for them, this will use 674 MB,
according to the xz manual page. Level -6 on the other hand
only needs 94 MB memory for compression.
This causes autopkgtest failures in the test-compressed-indexes
test, as not enough memory exists to proceed.
Change the other compression levels to 6 as well: The gzip
and bzip2 FileFd backends do not read them, and use their
code's default level which is 6, so do the same for external
methods.
Regression introduced in 8710a36a01c0cb1648926792c2ad05185535558e,
but such fields are unlikely in practice as it is just as simple to not
have a field at all with the same result of not having a value.
allow repositories to forbid arch:all for specific index targets
Debian has a Packages file for arch:all already, but the arch:any files
contain arch:all packages as well, so downloading it would be a total
waste of resources. Getting this solved is on the list of things to do,
but it is also the hardest part – for index targets like Contents the
situation is much easier and less server/client implementations are
involved so we might not want to stall them.
A repository can now declare via:
No-Support-for-Architecture-all: Packages
that even if an arch:all Packages exists, it shouldn't be downloaded, so
that support for Contents files can be added now.
The field uses the name of the target from the apt configuration for
simplicity and is negative by design as this field is intended to be
supported/needed only for a "short" time (one or two Debian releases).
While this commit theoretically supports any target, its expected to
only see "Packages" as a value in reality.
debListParser: ParseDepends: Only query native arch if needed
This makes the code parsing architecture lists slower, but on
the other hand, improves the more generic case of reading
dependencies from Packages files.
Change InternalReadLine to always use buffer.read() return value
This is mostly a documentation issue, as the size we want to
read is always less than or equal to the size of the buffer,
so the return value will be the same as the size argument.
Nonetheless, people wondered about it, and it seems clearer
to just always use the return value.
This further improves our performance, and rred on uncompressed
files now spents 78% of its time in writing. Which means that
we should really look at buffering those.
Use a hardcoded buffer size of 4096 to fix performance
The code uses memmove() to move parts of the buffer to the
front when the buffer is only partially read. By simply
reading one page at a time, the maximum size of bytes that
must be moved has a hard limit, and performance improves:
In one test case, consisting of a 430 MB Contents file,
and a 75K PDiff, applying the PDiff previously took about
48 seconds and now completes in 2 seconds.
Further speed up can be achieved by buffering writes, they
account for about 60% of the run-time now.
We don't need the buffer that often - only for ReadLine - as it is only
occasionally used, so it is actually more efficient to allocate it if
needed instead of statically by default. It also allows the caller to
influence the buffer size instead of hardcoding it.
The default implementation of ReadLine was very naive by just reading
each character one-by-one. That is kinda okay for libraries implementing
compression as they have internal buffers (but still not great), but
while working with files directly or via a pipe as there is no buffer
there so all those reads are in fact system calls.
This commit introduces an internal buffer in the FileFd implementation
which is only used by ReadLine. The more low-level Read and all other
actions remain unbuffered – they just changed to deal with potential
"left-overs" in the buffer correctly.
If we use the library to compress xz, still try to understand and pick
up the arguments we would have used to call xz to figure out which level
the user wants us to use instead of defaulting to level 6 (which is the
default level of xz).
follow dpkg and xz and use CRC64 for xz compression
dpkg switched from CRC32 to CRC64 in 777915108d9d36d022dc4fc4151a615fc95e5032 with the message:
| This is the default CRC used by the xz command-line tool, align with
| it and switch from CRC32 to CRC64. It should provide slightly better
| detection against damaged data, at a negligible speed difference.
shuffle compressor-specific code into private subclasses
This isn't implementing any new features, it is "just" moving code
around from FileFd methods which decided on each call how to handle the
request by including all logic for all possible compressor backends in
the method body to a model in which backend-specifics are implemented in
a FileFdPrivate subclass. This avoids a big chunk of #ifdef's and should
make it a tiny bit more obvious which backend uses which code.
The execution of the idea is slightly uglified by the need to preserve
ABI and API which causes liberal befriending.
projects / apt.git / log
