merge from mvo

* apt/cache.py:
  - re-work the logic in commit() to fail if installArchives() returns
    a unexpected result
* apt/progress/__init__.py:
  - catch exceptions in pm.DoInstall()

2 files changed, 24 insertions, 5 deletions

diff --git a/apt/cache.py b/apt/cache.py
index 828b167b..bb944041 100644
--- a/apt/cache.py
+++ b/apt/cache.py
@@ -314,8 +314,12 @@ class Cache(object):
             res = self.installArchives(pm, installProgress)
             if res == pm.ResultCompleted:
                 break
-            if res == pm.ResultFailed:
+            elif res == pm.ResultFailed:
                 raise SystemError("installArchives() failed")
+            elif res == pm.ResultIncomplete:
+                 pass
+            else:
+                 raise SystemError("internal-error: unknown result code from InstallArchives: %s" % res)
             # reload the fetcher for media swaping
             fetcher.Shutdown()
         return (res == pm.ResultCompleted)
diff --git a/apt/progress/__init__.py b/apt/progress/__init__.py
index 9f348ffd..8a9eb86f 100644
--- a/apt/progress/__init__.py
+++ b/apt/progress/__init__.py
@@ -284,7 +284,11 @@ class InstallProgress(DumbInstallProgress):
         return os.fork()
 
     def waitChild(self):
-        """Wait for child progress to exit."""
+        """Wait for child progress to exit.
+
+        The return values is the full status returned from os.waitpid()
+        (not only the return code).
+        """
         while True:
             try:
                 select.select([self.statusfd], [], [], self.selectTimeout)
@@ -304,11 +308,22 @@ class InstallProgress(DumbInstallProgress):
         return res
 
     def run(self, pm):
-        """Start installing."""
+        """Start installing. 
+        
+        Returns the PackageManager status:
+        (pm.ResultCompleted, pm.ResultFailed, pm.ResultIncomplete)
+        """
         pid = self.fork()
         if pid == 0:
-            # child
-            res = pm.DoInstall(self.writefd)
+            # pm.DoInstall might raise a exception,
+            # when this happens, we need to catch
+            # it, otherwise os._exit() is not run
+            # and the execution continues in the 
+            # parent code leading to very confusing bugs
+            try:
+                res = pm.DoInstall(self.writefd)
+            except Exception, e:
+                os._exit(pm.ResultFailed)
             os._exit(res)
         self.child_pid = pid
         res = self.waitChild()