Pungis work directory.

[Joel Andres Granados]

I ran pungi once and created a fedora iso.  When I ran it again with the 
same config file, and forgot to erase the previous work directory 
files,  pungi shows a traceback telling me that some file already exists.
I have two proposals for this situation.
1.  create a timestamp directory inside the working directory for each 
pungi run.   The problem with this approach is that the use is left with 
a bunch of directories that are named after whatever time.time() spit 
out (not very pretty).  But alas it does away with the ugly traceback 
message.
The diff for the first solution:

--- pungi-0.3.0 2007-04-02 23:17:25.000000000 +0200
+++ pungi-0.3.1-JG  2007-04-13 14:27:22.000000000 +0200
@@ -18,6 +18,7 @@
 import yum
 
 from ConfigParser import SafeConfigParser
+from time import time
 
 def main():
     # Set some default variables, can be overrided in config file
@@ -76,7 +77,8 @@
 
     if not opts.destdir == "*CONFFILE*":
         config.set('default', 'destdir', opts.destdir)
-
+    config.set('default', 'destdir', 
os.path.join(config.get('default','destdir'),
+                str(int(time()))))
     destdir = config.get('default', 'destdir')
 
     if not os.path.exists(destdir):

2. Just tell the user to erase the things he/she has in the directory.
The diff for the second solution:

--- pungi-0.3.0 2007-04-13 15:03:26.000000000 +0200
+++ pungi-0.3.1-JG  2007-04-13 15:02:22.000000000 +0200
@@ -18,6 +18,7 @@
 import yum
 
 from ConfigParser import SafeConfigParser
+from os.path import isdir
 
 def main():
     # Set some default variables, can be overrided in config file
@@ -77,7 +78,7 @@
     if not opts.destdir == "*CONFFILE*":
         config.set('default', 'destdir', opts.destdir)
        
-    destdir = config.get('default', 'destdir')
+    destdir = check_destdir(config.get('default', 'destdir'))
 
     if not os.path.exists(destdir):
         try:
@@ -180,4 +181,10 @@
         manifestfile.close()
         return pkglist
 
+    def check_destdir(workpath):
+        if isdir(workpath) and len(os.listdir(workpath)) > 0:
+            print >> sys.stderr, "Please erase all items from the 
directory %s before continuing." % workpath
+            exit(1)
+        return workpath
+
     main()