From c2709fd1bfab44db585e4f50162464f894fb4944 Mon Sep 17 00:00:00 2001
From: Babak Farrokhi <babak@farrokhi.net>
Date: Sun, 10 Apr 2016 15:36:29 +0430
Subject: [PATCH] fix layout with variable len addresses (close #4)

---
 dnseval.py | 36 ++++++++++++++++++++++++------------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/dnseval.py b/dnseval.py
index 36a4bff..992c43b 100755
--- a/dnseval.py
+++ b/dnseval.py
@@ -25,6 +25,8 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 
+import dns.rdatatype
+import dns.resolver
 import getopt
 import os
 import signal
@@ -32,9 +34,6 @@ import sys
 import time
 from statistics import stdev
 
-import dns.rdatatype
-import dns.resolver
-
 __VERSION__ = 1.0
 __PROGNAME__ = os.path.basename(sys.argv[0])
 should_stop = False
@@ -53,7 +52,7 @@ resolvers = [
 
 def usage():
     print('%s version %1.1f\n' % (__PROGNAME__, __VERSION__))
-    print('syntax: %s [-h] [-f server-list] [-c count] [-t type] [-w wait] hostname' % __PROGNAME__ )
+    print('syntax: %s [-h] [-f server-list] [-c count] [-t type] [-w wait] hostname' % __PROGNAME__)
     print('  -h  --help      show this help')
     print('  -f  --file      dns server list to use')
     print('  -c  --count     number of requests to send (default: 10)')
@@ -69,6 +68,14 @@ def signal_handler(sig, frame):
     should_stop = True  # pressed once, exit gracefully
 
 
+def widest_len(names):
+    width = 0
+    for s in names:
+        if len(s) > width:
+            width = len(s)
+    return width
+
+
 def dnsping(host, server, dnsrecord, timeout, count):
     resolver = dns.resolver.Resolver()
     resolver.nameservers = [server]
@@ -111,8 +118,7 @@ def dnsping(host, server, dnsrecord, timeout, count):
         r_avg = 0
         r_stddev = 0
 
-    print("%-15s    %-8.3f    %-8.3f    %-8.3f    %-8.3f    %%%d" % (
-        server, r_avg, r_min, r_max, r_stddev, r_lost_percent))
+    return (server, r_avg, r_min, r_max, r_stddev, r_lost_percent)
 
 
 def main():
@@ -159,18 +165,24 @@ def main():
 
     try:
         if fromfile:
-            f = open(inputfilename, 'rt')
+            with open(inputfilename, 'rt') as flist:
+                f = flist.read().splitlines()
         else:
             f = resolvers
-        print('server             avg(ms)     min(ms)     max(ms)     stddev(ms)  lost(%)')
-        print('--------------------------------------------------------------------------')
+        width = widest_len(f)
+        blanks = (width - 5) * ' '
+        print('server ', blanks, ' avg(ms)     min(ms)     max(ms)     stddev(ms)  lost(%)')
+        print((60 + width) * '-')
         for server in f:
             s = server.strip()
             if not s:
                 continue
-            dnsping(hostname, s, dnsrecord, waittime, count)
-        if fromfile:
-            f.close()
+            (server, r_avg, r_min, r_max, r_stddev, r_lost_percent) = dnsping(hostname, s, dnsrecord, waittime, count)
+
+            server = server.ljust(width + 1)
+            print("%s    %-8.3f    %-8.3f    %-8.3f    %-8.3f    %%%d" % (
+                server, r_avg, r_min, r_max, r_stddev, r_lost_percent))
+
     except Exception as e:
         print('error: %s' % e)
         exit(1)