Make immediate configuration optional

The benefits of immediate configuration are that Essential packages
will be configured immediately, so if they are wrongly not working
without being configured they won't fail later packages.

However, we've reached the point where dependencies on the essential set
are too complex for immediate configuration to always work, causing
installations to error out at the end, despite having succeeded, because
we did not correctly return the error here and did not check for pending
errors before running dpkg.

Given that we check and configure any packages at the end that have not
been configured yet, or fail if we can't configure them; making
immediate configuration optional is the best way forward - it orders as
it does now, but then does not spuriously fail after having successfully
installed everything.

Closes: #973305, #188161, #211075, #649588
LP: #1871268

1 files changed, 12 insertions, 4 deletions

diff --git a/apt-pkg/packagemanager.cc b/apt-pkg/packagemanager.cc
index a1b3f4537..0c6998def 100644
--- a/apt-pkg/packagemanager.cc
+++ b/apt-pkg/packagemanager.cc
@@ -1006,10 +1006,18 @@ bool pkgPackageManager::SmartUnPack(PkgIterator Pkg, bool const Immediate, int c
       return false;
 
    if (Immediate == true) {
-      // Perform immediate configuration of the package. 
-         if (SmartConfigure(Pkg, Depth + 1) == false)
-            _error->Warning(_("Could not perform immediate configuration on '%s'. "
-               "Please see man 5 apt.conf under APT::Immediate-Configure for details. (%d)"),Pkg.FullName().c_str(),2);
+      // Perform immediate configuration of the package.
+      _error->PushToStack();
+      bool configured = SmartConfigure(Pkg, Depth + 1);
+      _error->RevertToStack();
+
+      if (not configured && Debug) {
+	 clog << OutputInDepth(Depth);
+	 ioprintf(clog, _("Could not perform immediate configuration on '%s'. "
+			   "Please see man 5 apt.conf under APT::Immediate-Configure for details. (%d)"),
+			 Pkg.FullName().c_str(), 2);
+	 clog << endl;
+      }
    }
    
    return true;