From c55c0ade9ea7f084111884b282c0ffd632ad6c55 Mon Sep 17 00:00:00 2001 From: Julian Andres Klode Date: Tue, 18 Dec 2018 14:50:25 +0100 Subject: Introduce experimental 'never' pinning for sources This allows disabling a repository by pinning it to 'never', which is internally translated to a value of -32768 (or whatever the minimum of short is). This overrides any other pin for that repository. It can be used to make sure certain sources are never used; for example, in unattended-upgrades. To prevent semantic changes to existing files, we substitute min + 1 for every pin-priority: . This is a temporary solution, as we are waiting for an ABI break. To add pins with that value, the special Pin-Priority "never" may be used for now. It's unclear if that will persist, or if the interface will change eventually. (cherry picked from commit 8bb2a91a070170d7d8e71206d1c66a26809bdbc3) LP: #1814727 (cherry picked from commit f52e7a2040f461fb37f88751f5a42a5d5c130441) --- apt-pkg/policy.cc | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) (limited to 'apt-pkg') diff --git a/apt-pkg/policy.cc b/apt-pkg/policy.cc index 030bab26b..097373935 100644 --- a/apt-pkg/policy.cc +++ b/apt-pkg/policy.cc @@ -39,6 +39,8 @@ using namespace std; +constexpr short NEVER_PIN = std::numeric_limits::min(); + // Policy::Init - Startup and bind to a cache /*{{{*/ // --------------------------------------------------------------------- /* Set the defaults for operation. The default mode with no loaded policy @@ -108,7 +110,7 @@ bool pkgPolicy::InitDefaults() pkgVersionMatch Match(I->Data,I->Type); for (pkgCache::PkgFileIterator F = Cache->FileBegin(); F != Cache->FileEnd(); ++F) { - if (Fixed[F->ID] == false && Match.FileMatch(F) == true) + if ((Fixed[F->ID] == false || I->Priority == NEVER_PIN) && PFPriority[F->ID] != NEVER_PIN && Match.FileMatch(F) == true) { PFPriority[F->ID] = I->Priority; @@ -272,7 +274,14 @@ APT_PURE signed short pkgPolicy::GetPriority(pkgCache::PkgIterator const &Pkg) APT_PURE signed short pkgPolicy::GetPriority(pkgCache::VerIterator const &Ver, bool ConsiderFiles) { if (VerPins[Ver->ID].Type != pkgVersionMatch::None) - return VerPins[Ver->ID].Priority; + { + // If all sources are never pins, the never pin wins. + if (VerPins[Ver->ID].Priority == NEVER_PIN) + return NEVER_PIN; + for (pkgCache::VerFileIterator file = Ver.FileList(); file.end() == false; file++) + if (GetPriority(file.File()) != NEVER_PIN) + return VerPins[Ver->ID].Priority; + } if (!ConsiderFiles) return 0; @@ -389,9 +398,17 @@ bool ReadPinFile(pkgPolicy &Plcy,string File) for (; Word != End && isspace(*Word) != 0; Word++); _error->PushToStack(); - int const priority = Tags.FindI("Pin-Priority", 0); + std::string sPriority = Tags.FindS("Pin-Priority"); + int priority = sPriority == "never" ? NEVER_PIN : Tags.FindI("Pin-Priority", 0); bool const newError = _error->PendingError(); _error->MergeWithStack(); + + if (sPriority == "never" && not Name.empty()) + return _error->Error(_("%s: The special 'Pin-Priority: %s' can only be used for 'Package: *' records"), File.c_str(), "never"); + + // Silently clamp the never pin to never pin + 1 + if (priority == NEVER_PIN && sPriority != "never") + priority = NEVER_PIN + 1; if (priority < std::numeric_limits::min() || priority > std::numeric_limits::max() || newError) { -- cgit v1.2.3