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-rw-r--r--apt-pkg/solver3.cc49
1 files changed, 30 insertions, 19 deletions
diff --git a/apt-pkg/solver3.cc b/apt-pkg/solver3.cc
index f2e4360ff..c4fb567e1 100644
--- a/apt-pkg/solver3.cc
+++ b/apt-pkg/solver3.cc
@@ -256,18 +256,28 @@ std::string APT::Solver::Work::toString(pkgCache &cache) const
return out.str();
}
+inline APT::Solver::Var APT::Solver::bestReason(APT::Solver::Clause const *clause, APT::Solver::Var var) const
+{
+ if (not clause)
+ return Var{};
+ if (clause->reason == var)
+ for (auto choice : clause->solutions)
+ if ((*this)[choice].decision != Decision::NONE)
+ return choice;
+ return clause->reason;
+}
+
// Prints an implication graph part of the form A -> B -> C, possibly with "not"
std::string APT::Solver::WhyStr(Var reason) const
{
std::vector<std::string> out;
-
while (not reason.empty())
{
if ((*this)[reason].decision == Decision::MUSTNOT)
out.push_back(std::string("not ") + reason.toString(cache));
else
out.push_back(reason.toString(cache));
- reason = (*this)[reason].reason;
+ reason = bestReason((*this)[reason].reason, reason);
}
std::string outstr;
@@ -337,13 +347,13 @@ bool APT::Solver::Obsolete(pkgCache::PkgIterator pkg) const
pkgObsolete[pkg] = 2;
return true;
}
-bool APT::Solver::Assume(Var var, bool decision, Var reason)
+bool APT::Solver::Assume(Var var, bool decision, const Clause *reason)
{
choices.push_back(solved.size());
return Enqueue(var, decision, std::move(reason));
}
-bool APT::Solver::Enqueue(Var var, bool decision, Var reason)
+bool APT::Solver::Enqueue(Var var, bool decision, const Clause *reason)
{
auto &state = (*this)[var];
auto decisionCast = decision ? Decision::MUST : Decision::MUSTNOT;
@@ -351,7 +361,7 @@ bool APT::Solver::Enqueue(Var var, bool decision, Var reason)
if (state.decision != Decision::NONE)
{
if (state.decision != decisionCast)
- return _error->Error("Conflict: %s -> %s%s but %s", WhyStr(reason).c_str(), decision ? "" : "not ", var.toString(cache).c_str(), WhyStr(var).c_str());
+ return _error->Error("Conflict: %s -> %s%s but %s", WhyStr(bestReason(reason, var)).c_str(), decision ? "" : "not ", var.toString(cache).c_str(), WhyStr(var).c_str());
return true;
}
@@ -360,7 +370,7 @@ bool APT::Solver::Enqueue(Var var, bool decision, Var reason)
state.reason = reason;
if (unlikely(debug >= 1))
- std::cerr << "[" << depth() << "] " << (decision ? "Install" : "Reject") << ":" << var.toString(cache) << " (" << WhyStr(state.reason) << ")\n";
+ std::cerr << "[" << depth() << "] " << (decision ? "Install" : "Reject") << ":" << var.toString(cache) << " (" << WhyStr(bestReason(reason, var)) << ")\n";
solved.push_back(Solved{var, std::nullopt});
propQ.push(var);
@@ -386,7 +396,7 @@ bool APT::Solver::Propagate()
continue;
if (unlikely(debug >= 3))
std::cerr << "Propagate " << var.toString(cache) << " to NOT " << rclause->reason.toString(cache) << " for dep " << const_cast<Clause *>(rclause)->toString(cache) << std::endl;
- if (not Enqueue(rclause->reason, false, var))
+ if (not Enqueue(rclause->reason, false, rclause))
return false;
}
}
@@ -416,7 +426,7 @@ bool APT::Solver::Propagate()
{
// Find the variable that must be chosen and enqueue it as a fact
for (auto sol : rclause->solutions)
- if ((*this)[sol].decision == Decision::NONE && not Enqueue(sol, true, rclause->reason))
+ if ((*this)[sol].decision == Decision::NONE && not Enqueue(sol, true, rclause))
return false;
}
continue;
@@ -427,7 +437,7 @@ bool APT::Solver::Propagate()
if (unlikely(debug >= 3))
std::cerr << "Propagate NOT " << var.toString(cache) << " to " << rclause->reason.toString(cache) << " for dep " << const_cast<Clause *>(rclause)->toString(cache) << std::endl;
- if (not Enqueue(rclause->reason, false, var)) // Last version invalidated
+ if (not Enqueue(rclause->reason, false, rclause)) // Last version invalidated
return false;
}
}
@@ -680,7 +690,7 @@ void APT::Solver::UndoOne()
std::cerr << "Unassign " << solvedItem.assigned.toString(cache) << "\n";
auto &state = (*this)[solvedItem.assigned];
state.decision = Decision::NONE;
- state.reason = Var();
+ state.reason = nullptr;
state.depth = 0;
}
@@ -747,7 +757,7 @@ bool APT::Solver::AddWork(Work &&w)
if (w.clause->negative)
{
for (auto var : w.clause->solutions)
- if (not Enqueue(var, false, w.clause->reason))
+ if (not Enqueue(var, false, w.clause))
return false;
}
else if (not w.clause->solutions.empty())
@@ -755,7 +765,7 @@ bool APT::Solver::AddWork(Work &&w)
if (unlikely(debug >= 3 && w.clause->optional))
std::cerr << "Enqueuing Recommends " << w.clause->toString(cache) << std::endl;
if (w.clause->solutions.size() == 1 && not w.clause->optional)
- return Enqueue(w.clause->solutions[0], true, w.clause->reason);
+ return Enqueue(w.clause->solutions[0], true, w.clause);
w.size = std::count_if(w.clause->solutions.begin(), w.clause->solutions.end(), [this](auto V)
{ return (*this)[V].decision != Decision::MUSTNOT; });
@@ -825,7 +835,7 @@ bool APT::Solver::Solve()
}
if (unlikely(debug >= 3))
std::cerr << "(try it: " << sol.toString(cache) << ")\n";
- if (not Enqueue(sol, true, item.clause->reason) && not Pop())
+ if (not Enqueue(sol, true, item.clause) && not Pop())
return false;
foundSolution = true;
break;
@@ -878,7 +888,7 @@ bool APT::Solver::FromDepCache(pkgDepCache &depcache)
{
if (unlikely(debug >= 1))
std::cerr << "Hold " << P.FullName() << "\n";
- if (P->CurrentVer ? not Enqueue(Var(P.CurrentVer()), true, {}) : not Enqueue(Var(P), false, Var()))
+ if (P->CurrentVer ? not Enqueue(Var(P.CurrentVer()), true) : not Enqueue(Var(P), false))
return false;
}
else if (state.Delete() // Normal delete request.
@@ -888,7 +898,7 @@ bool APT::Solver::FromDepCache(pkgDepCache &depcache)
{
if (unlikely(debug >= 1))
std::cerr << "Delete " << P.FullName() << "\n";
- if (not Enqueue(Var(P), false, Var()))
+ if (not Enqueue(Var(P), false))
return false;
}
else if (state.Install() || (state.Keep() && P->CurrentVer))
@@ -915,7 +925,7 @@ bool APT::Solver::FromDepCache(pkgDepCache &depcache)
if (not isOptional)
{
// Pre-empt the non-optional requests, as we don't want to queue them, we can just "unit propagate" here.
- if (depcache[P].Keep() ? not Enqueue(Var(P), true, {}) : not Enqueue(Var(depcache.GetCandidateVersion(P)), true, {}))
+ if (depcache[P].Keep() ? not Enqueue(Var(P), true) : not Enqueue(Var(depcache.GetCandidateVersion(P)), true))
return false;
}
else
@@ -977,9 +987,10 @@ bool APT::Solver::ToDepCache(pkgDepCache &depcache) const
if ((*this)[V].decision == Decision::MUST)
cand = V;
- auto reason = (*this)[cand].reason;
+ auto reasonClause = (*this)[cand].reason;
+ auto reason = reasonClause ? reasonClause->reason : Var();
if (auto RP = reason.Pkg(); RP == P.MapPointer())
- reason = (*this)[P].reason;
+ reason = (*this)[P].reason ? (*this)[P].reason->reason : Var();
if (cand != P.CurrentVer())
{
@@ -996,7 +1007,7 @@ bool APT::Solver::ToDepCache(pkgDepCache &depcache) const
}
else if (P->CurrentVer || depcache[P].Install())
{
- depcache.MarkDelete(P, false, 0, (*this)[P].reason.empty());
+ depcache.MarkDelete(P, false, 0, not(*this)[P].reason);
depcache[P].Marked = 0;
depcache[P].Garbage = 1;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2026-07-18 22:26:41 +0000