* These errors would become much more seen when people start to play

with the package-manager's cancel button. I have seen it a lot
  while playing with it. And when this happens there is no way
  to explain this to users.

faik@iago pisi $ sudo ./pisi-cli it /home/faik/hdparm-6.7-5-4.pisi
Password:
Kurulum sırası: hdparm
hdparm paketi, versiyon 6.7, sürüm 5, inşa 4 kuruluyor
disabled
Aynı versiyona sahip paketi yeniden yerleştireyim mi? (evet/hayır)e
Sistem Hatası: Program Sonlandırıldı.
Dosya '/var/lib/pisi/package/hdparm-6.7-5/files.xml' bulunamadı.

Patch prevents these errors by blocking keyboard interrupts between
critical paths. When the critical path is passed if any interrupts
were caught while in this path the interrupt is raised.

pisi/atomicoperations.py

@@ -106,6 +106,9 @@ class Install(AtomicOperation):
         self.ask_reinstall = ask_reinstall
         self.check_requirements()
         self.check_relations()
+
+        ctx.disable_keyboard_interrupts()
+
         self.check_reinstall()
         self.extract_install()
         self.store_pisi_files()
@@ -120,6 +123,8 @@ class Install(AtomicOperation):
             txn.abort()
             raise e
 
+        ctx.enable_keyboard_interrupts()
+
         ctx.ui.close()
         if self.upgrade:
             event = pisi.ui.upgraded

pisi/comariface.py

@@ -65,6 +65,10 @@ def wait_for_result(com, package_name=None):
         except KeyboardInterrupt:
             raise
         except Exception, e: #FIXME: what exception could we catch here, replace with that.
+            # TODO: we return here but we can also set self.config_later?
+            if ctx.keyboard_interrupt_pending():
+                return
+
             # Comar postInstall does a "service comar restart" which cuts
             # our precious communication link, so we waitsss
             if package_name == "comar":

pisi/context.py

@@ -12,9 +12,13 @@
 
 # global variables here
 
+import signal
+
 import pisi.constants
+import pisi.signalhandler
 
 const = pisi.constants.Constants()
+sig = pisi.signalhandler.SignalHandler()
 
 config = None
 
@@ -74,3 +78,15 @@ def txn_proc(proc, txn = None):
         return retval
     else:
         return proc(txn)
+
+def disable_keyboard_interrupts():
+    sig.disable_signal(signal.SIGINT)
+
+def enable_keyboard_interrupts():
+    sig.enable_signal(signal.SIGINT)
+
+def keyboard_interrupt_disabled():
+    return sig.signal_disabled(signal.SIGINT)
+
+def keyboard_interrupt_pending():
+    return sig.signal_pending(signal.SIGINT)

pisi/signalhandler.py

@@ -0,0 +1,54 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2006, TUBITAK/UEKAE
+#
+# 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.
+#
+# Please read the COPYING file.
+#
+
+import signal
+
+exception = {
+    signal.SIGINT:KeyboardInterrupt
+    }
+
+class SignalHandler:
+
+    def __init__(self):
+        self.pending_signals = []
+        self.disabled_signals = []
+
+    def signal_handler(self, sig, frame):
+        signal.signal(sig, signal.SIG_IGN)
+        if sig not in self.pending_signals:
+            self.pending_signals.append(sig)
+            
+    def clear_pending_signal(self, sig):
+        if sig in self.pending_signals:
+            self.pending_signals.remove(sig)
+
+    def disable_signal(self, sig):
+        signal.signal(sig, self.signal_handler)
+
+        if sig not in self.disabled_signals:
+            self.disabled_signals.append(sig)
+
+    def enable_signal(self, sig):
+        signal.signal(sig, signal.SIG_DFL)
+
+        if sig in self.disabled_signals:
+            self.disabled_signals.remove(sig)
+
+        if sig in self.pending_signals:
+            self.clear_pending_signal(sig)
+            raise exception[sig]
+
+    def signal_disabled(self, sig):
+        return sig in self.disabled_signals
+
+    def signal_pending(self, sig):
+        return sig in self.pending_signals