You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
399 lines
15 KiB
399 lines
15 KiB
# -*- coding: utf-8 -*-
|
|
|
|
# Copyright (C) 2012 Niels Thykier <niels@thykier.net>
|
|
|
|
# This program is free software; you can redistribute it and/or modify
|
|
# it under the terms of the GNU General Public License as published by
|
|
# the Free Software Foundation; either version 2 of the License, or
|
|
# (at your option) any later version.
|
|
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU General Public License for more details.
|
|
|
|
from collections import defaultdict
|
|
from contextlib import contextmanager
|
|
|
|
from britney_util import ifilter_except, iter_except
|
|
from installability.solver import InstallabilitySolver
|
|
|
|
class _RelationBuilder(object):
|
|
"""Private helper class to "build" relations"""
|
|
|
|
def __init__(self, itbuilder, binary):
|
|
self._itbuilder = itbuilder
|
|
self._binary = binary
|
|
binary_data = itbuilder._package_table[binary]
|
|
self._new_deps = set(binary_data[0])
|
|
self._new_breaks = set(binary_data[1])
|
|
|
|
|
|
def add_dependency_clause(self, or_clause):
|
|
"""Add a dependency clause
|
|
|
|
The clause must be a sequence of (name, version, architecture)
|
|
tuples. The clause is an OR clause, i.e. any tuple in the
|
|
sequence can satisfy the relation. It is irrelevant if the
|
|
dependency is from the "Depends" or the "Pre-Depends" field.
|
|
|
|
Note that is the sequence is empty, the dependency is assumed
|
|
to be unsatisfiable.
|
|
|
|
The binaries in the clause are not required to have been added
|
|
to the InstallabilityTesterBuilder when this method is called.
|
|
However, they must be added before the "build()" method is
|
|
called.
|
|
"""
|
|
clause = self._itbuilder._intern_set(or_clause)
|
|
binary = self._binary
|
|
itbuilder = self._itbuilder
|
|
okay = False
|
|
for dep_tuple in clause:
|
|
okay = True
|
|
rdeps, _, rdep_relations = itbuilder._reverse_relations(dep_tuple)
|
|
rdeps.add(binary)
|
|
rdep_relations.add(clause)
|
|
|
|
self._new_deps.add(clause)
|
|
if not okay:
|
|
self._itbuilder._broken.add(binary)
|
|
|
|
|
|
def add_breaks(self, broken_binary):
|
|
"""Add a Breaks-clause
|
|
|
|
Marks the given binary as being broken by the current
|
|
package. That is, the given package satisfies a relation
|
|
in either the "Breaks" or the "Conflicts" field. The binary
|
|
given must be a (name, version, architecture)-tuple.
|
|
|
|
The binary is not required to have been added to the
|
|
InstallabilityTesterBuilder when this method is called. However,
|
|
it must be added before the "build()" method is called.
|
|
"""
|
|
itbuilder = self._itbuilder
|
|
self._new_breaks.add(broken_binary)
|
|
reverse_relations = itbuilder._reverse_relations(broken_binary)
|
|
reverse_relations[1].add(self._binary)
|
|
|
|
|
|
def _commit(self):
|
|
itbuilder = self._itbuilder
|
|
data = (itbuilder._intern_set(self._new_deps),
|
|
itbuilder._intern_set(self._new_breaks))
|
|
itbuilder._package_table[self._binary] = data
|
|
|
|
|
|
class InstallabilityTesterBuilder(object):
|
|
"""Builder to create instances of InstallabilityTester"""
|
|
|
|
def __init__(self):
|
|
self._package_table = {}
|
|
self._reverse_package_table = {}
|
|
self._essentials = set()
|
|
self._testing = set()
|
|
self._internmap = {}
|
|
self._broken = set()
|
|
|
|
|
|
def add_binary(self, binary, essential=False, in_testing=False,
|
|
frozenset=frozenset):
|
|
"""Add a new binary package
|
|
|
|
Adds a new binary package. The binary must be given as a
|
|
(name, version, architecture)-tuple. Returns True if this
|
|
binary is new (i.e. has never been added before) or False
|
|
otherwise.
|
|
|
|
Keyword arguments:
|
|
* essential - Whether this package is "Essential: yes".
|
|
* in_testing - Whether this package is in testing.
|
|
|
|
The frozenset argument is a private optimisation.
|
|
|
|
Cave-at: arch:all packages should be "re-mapped" to given
|
|
architecture. That is, (pkg, version, "all") should be
|
|
added as:
|
|
|
|
for arch in architectures:
|
|
binary = (pkg, version, arch)
|
|
it.add_binary(binary)
|
|
|
|
The resulting InstallabilityTester relies on this for
|
|
correctness!
|
|
"""
|
|
# Note, even with a dup, we need to do these
|
|
if in_testing:
|
|
self._testing.add(binary)
|
|
if essential:
|
|
self._essentials.add(binary)
|
|
|
|
if binary not in self._package_table:
|
|
# Allow binaries to be added multiple times (happens
|
|
# when sid and testing have the same version)
|
|
self._package_table[binary] = (frozenset(), frozenset())
|
|
return True
|
|
return False
|
|
|
|
|
|
@contextmanager
|
|
def relation_builder(self, binary):
|
|
"""Returns a _RelationBuilder for a given binary [context]
|
|
|
|
This method returns a context-managed _RelationBuilder for a
|
|
given binary. So it should be used in a "with"-statment,
|
|
like:
|
|
|
|
with it.relation_builder(binary) as rel:
|
|
rel.add_dependency_clause(dependency_clause)
|
|
rel.add_breaks(pkgtuple)
|
|
...
|
|
|
|
The binary given must be a (name, version, architecture)-tuple.
|
|
|
|
Note, this method is optimised to be called at most once per
|
|
binary.
|
|
"""
|
|
if binary not in self._package_table:
|
|
raise ValueError("Binary %s/%s/%s does not exist" % binary)
|
|
rel = _RelationBuilder(self, binary)
|
|
yield rel
|
|
rel._commit()
|
|
|
|
|
|
def _intern_set(self, s, frozenset=frozenset):
|
|
"""Freeze and intern a given sequence (set variant of intern())
|
|
|
|
Given a sequence, create a frozenset copy (if it is not
|
|
already a frozenset) and intern that frozen set. Returns the
|
|
interned set.
|
|
|
|
At first glance, interning sets may seem absurd. However,
|
|
it does enable memory savings of up to 600MB when applied
|
|
to the "inner" sets of the dependency clauses and all the
|
|
conflicts relations as well.
|
|
"""
|
|
if type(s) == frozenset:
|
|
fset = s
|
|
else:
|
|
fset = frozenset(s)
|
|
if fset in self._internmap:
|
|
return self._internmap[fset]
|
|
self._internmap[fset] = fset
|
|
return fset
|
|
|
|
|
|
def _reverse_relations(self, binary, set=set):
|
|
"""Return the reverse relations for a binary
|
|
|
|
Fetch the reverse relations for a given binary, which are
|
|
created lazily.
|
|
"""
|
|
|
|
if binary in self._reverse_package_table:
|
|
return self._reverse_package_table[binary]
|
|
rel = [set(), set(), set()]
|
|
self._reverse_package_table[binary] = rel
|
|
return rel
|
|
|
|
def build(self):
|
|
"""Compile the installability tester
|
|
|
|
This method will compile an installability tester from the
|
|
information given and (where possible) try to optimise a
|
|
few things.
|
|
"""
|
|
package_table = self._package_table
|
|
reverse_package_table = self._reverse_package_table
|
|
intern_set = self._intern_set
|
|
safe_set = set()
|
|
broken = self._broken
|
|
not_broken = ifilter_except(broken)
|
|
check = set(broken)
|
|
|
|
def safe_set_satisfies(t):
|
|
"""Check if t's dependencies can be satisfied by the safe set"""
|
|
if not package_table[t][0]:
|
|
# If it has no dependencies at all, then it is safe. :)
|
|
return True
|
|
for depgroup in package_table[t][0]:
|
|
if not any(dep for dep in depgroup if dep in safe_set):
|
|
return False
|
|
return True
|
|
|
|
|
|
# Merge reverse conflicts with conflicts - this saves some
|
|
# operations in _check_loop since we only have to check one
|
|
# set (instead of two) and we remove a few duplicates here
|
|
# and there.
|
|
#
|
|
# At the same time, intern the rdep sets
|
|
for pkg in reverse_package_table:
|
|
if pkg not in package_table:
|
|
raise RuntimeError("%s/%s/%s referenced but not added!" % pkg)
|
|
deps, con = package_table[pkg]
|
|
rdeps, rcon, rdep_relations = reverse_package_table[pkg]
|
|
if rcon:
|
|
if not con:
|
|
con = intern_set(rcon)
|
|
else:
|
|
con = intern_set(con | rcon)
|
|
package_table[pkg] = (deps, con)
|
|
reverse_package_table[pkg] = (intern_set(rdeps), con,
|
|
intern_set(rdep_relations))
|
|
|
|
# Check if we can expand broken.
|
|
for t in not_broken(iter_except(check.pop, KeyError)):
|
|
# This package is not known to be broken... but it might be now
|
|
isb = False
|
|
for depgroup in package_table[t][0]:
|
|
if not any(not_broken(depgroup)):
|
|
# A single clause is unsatisfiable, the
|
|
# package can never be installed - add it to
|
|
# broken.
|
|
isb = True
|
|
break
|
|
|
|
if not isb:
|
|
continue
|
|
|
|
broken.add(t)
|
|
|
|
if t not in reverse_package_table:
|
|
continue
|
|
check.update(reverse_package_table[t][0] - broken)
|
|
|
|
if broken:
|
|
# Since a broken package will never be installable, nothing that depends on it
|
|
# will ever be installable. Thus, there is no point in keeping relations on
|
|
# the broken package.
|
|
seen = set()
|
|
empty_set = frozenset()
|
|
null_data = (frozenset([empty_set]), empty_set)
|
|
for b in (x for x in broken if x in reverse_package_table):
|
|
for rdep in (r for r in not_broken(reverse_package_table[b][0])
|
|
if r not in seen):
|
|
ndep = intern_set((x - broken) for x in package_table[rdep][0])
|
|
package_table[rdep] = (ndep, package_table[rdep][1] - broken)
|
|
seen.add(rdep)
|
|
|
|
# Since they won't affect the installability of any other package, we might as
|
|
# as well null their data. This memory for these packages, but likely there
|
|
# will only be a handful of these "at best" (fsvo of "best")
|
|
for b in broken:
|
|
package_table[b] = null_data
|
|
if b in reverse_package_table:
|
|
del reverse_package_table[b]
|
|
|
|
# Now find an initial safe set (if any)
|
|
check = set()
|
|
for pkg in package_table:
|
|
|
|
if package_table[pkg][1]:
|
|
# has (reverse) conflicts - not safe
|
|
continue
|
|
if not safe_set_satisfies(pkg):
|
|
continue
|
|
safe_set.add(pkg)
|
|
if pkg in reverse_package_table:
|
|
# add all rdeps (except those already in the safe_set)
|
|
check.update(reverse_package_table[pkg][0] - safe_set)
|
|
|
|
# Check if we can expand the initial safe set
|
|
for pkg in iter_except(check.pop, KeyError):
|
|
if package_table[pkg][1]:
|
|
# has (reverse) conflicts - not safe
|
|
continue
|
|
if safe_set_satisfies(pkg):
|
|
safe_set.add(pkg)
|
|
if pkg in reverse_package_table:
|
|
# add all rdeps (except those already in the safe_set)
|
|
check.update(reverse_package_table[pkg][0] - safe_set)
|
|
|
|
eqv_table = self._build_eqv_packages_table(package_table,
|
|
reverse_package_table)
|
|
|
|
return InstallabilitySolver(package_table,
|
|
reverse_package_table,
|
|
self._testing, self._broken,
|
|
self._essentials, safe_set,
|
|
eqv_table)
|
|
|
|
|
|
def _build_eqv_packages_table(self, package_table,
|
|
reverse_package_table,
|
|
frozenset=frozenset):
|
|
"""Attempt to build a table of equivalent packages
|
|
|
|
This method attempts to create a table of packages that are
|
|
equivalent (in terms of installability). If two packages (A
|
|
and B) are equivalent then testing the installability of A is
|
|
the same as testing the installability of B. This equivalency
|
|
also applies to co-installability.
|
|
|
|
The example cases:
|
|
* aspell-*
|
|
* ispell-*
|
|
|
|
Cases that do *not* apply:
|
|
* MTA's
|
|
|
|
The theory:
|
|
|
|
The packages A and B are equivalent iff:
|
|
|
|
reverse_depends(A) == reverse_depends(B) AND
|
|
conflicts(A) == conflicts(B) AND
|
|
depends(A) == depends(B)
|
|
|
|
Where "reverse_depends(X)" is the set of reverse dependencies
|
|
of X, "conflicts(X)" is the set of negative dependencies of X
|
|
(Breaks and Conflicts plus the reverse ones of those combined)
|
|
and "depends(X)" is the set of strong dependencies of X
|
|
(Depends and Pre-Depends combined).
|
|
|
|
To be honest, we are actually equally interested another
|
|
property as well, namely substitutability. The package A can
|
|
always used instead of B, iff:
|
|
|
|
reverse_depends(A) >= reverse_depends(B) AND
|
|
conflicts(A) <= conflicts(B) AND
|
|
depends(A) == depends(B)
|
|
|
|
(With the same definitions as above). Note that equivalency
|
|
is just a special-case of substitutability, where A and B can
|
|
substitute each other (i.e. a two-way substituation).
|
|
|
|
Finally, note that the "depends(A) == depends(B)" for
|
|
substitutability is actually not a strict requirement. There
|
|
are cases where those sets are different without affecting the
|
|
property.
|
|
"""
|
|
# Despite talking about substitutability, the method currently
|
|
# only finds the equivalence cases. Lets leave
|
|
# substitutability for a future version.
|
|
|
|
find_eqv_table = defaultdict(list)
|
|
eqv_table = {}
|
|
|
|
for pkg in reverse_package_table:
|
|
rdeps = reverse_package_table[pkg][2]
|
|
if not rdeps:
|
|
# we don't care for things without rdeps (because
|
|
# it is not worth it)
|
|
continue
|
|
deps, con = package_table[pkg]
|
|
ekey = (deps, con, rdeps)
|
|
find_eqv_table[ekey].append(pkg)
|
|
|
|
for pkg_list in find_eqv_table.values():
|
|
if len(pkg_list) < 2:
|
|
continue
|
|
|
|
eqv_set = frozenset(pkg_list)
|
|
for pkg in pkg_list:
|
|
eqv_table[pkg] = eqv_set
|
|
|
|
return eqv_table
|