tools/kvm_stat: Add Python 3 support to kvm_stat

Make kvm_stat support Python 3 by changing the use of "print" to a
function rather than a statement, switching from "iteritems" and
"iterkeys" (removed in Python 3) to "items" and "keys" respectively,
and decoding bytes to strings when dealing with text.

With this change, kvm_stat is usable with Python 2.6 and greater.
Signed-off-by: NJeremy Cline <jeremy@jcline.org>
Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>

tools/kvm/kvm_stat/kvm_stat

@@ -19,9 +19,11 @@ Three different ways of output formatting are available:
 
 The data is sampled from the KVM's debugfs entries and its perf events.
 """
+from __future__ import print_function
 
 import curses
 import sys
+import locale
 import os
 import time
 import optparse
@@ -225,6 +227,8 @@ IOCTL_NUMBERS = {
     'RESET':       0x00002403,
 }
 
+ENCODING = locale.getpreferredencoding(False)
+
 
 class Arch(object):
     """Encapsulates global architecture specific data.
@@ -666,7 +670,7 @@ class TracepointProvider(Provider):
         """Returns 'event name: current value' for all enabled events."""
         ret = defaultdict(int)
         for group in self.group_leaders:
-            for name, val in group.read().iteritems():
+            for name, val in group.read().items():
                 if name in self._fields:
                     ret[name] += val
         return ret
@@ -955,7 +959,7 @@ class Tui(object):
         except:
             raise Exception
         for line in child.stdout:
-            line = line.lstrip().split(' ', 1)
+            line = line.decode(ENCODING).lstrip().split(' ', 1)
             # perform a sanity check before calling the more expensive
             # function to possibly extract the guest name
             if ' -name ' in line[1]:
@@ -1005,7 +1009,7 @@ class Tui(object):
         name = ''
         try:
             line = open('/proc/{}/cmdline'
-                        .format(pid), 'rb').read().split('\0')
+                        .format(pid), 'r').read().split('\0')
             parms = line[line.index('-name') + 1].split(',')
             while '' in parms:
                 # commas are escaped (i.e. ',,'), hence e.g. 'foo,bar' results
@@ -1170,7 +1174,7 @@ class Tui(object):
                                .format(self.stats.fields_filter))
             self.screen.addstr(3, 0, "New regex: ")
             curses.echo()
-            regex = self.screen.getstr()
+            regex = self.screen.getstr().decode(ENCODING)
             curses.noecho()
             if len(regex) == 0:
                 self.stats.fields_filter = DEFAULT_REGEX
@@ -1204,7 +1208,7 @@ class Tui(object):
 
             curses.echo()
             self.screen.addstr(3, 0, "Pid [0 or pid]: ")
-            pid = self.screen.getstr()
+            pid = self.screen.getstr().decode(ENCODING)
             curses.noecho()
 
             try:
@@ -1233,7 +1237,7 @@ class Tui(object):
             self.screen.addstr(2, 0, 'Change delay from %.1fs to ' %
                                self._delay_regular)
             curses.echo()
-            val = self.screen.getstr()
+            val = self.screen.getstr().decode(ENCODING)
             curses.noecho()
 
             try:
@@ -1273,7 +1277,7 @@ class Tui(object):
             self.print_all_gnames(7)
             curses.echo()
             self.screen.addstr(3, 0, "Guest [ENTER or guest]: ")
-            gname = self.screen.getstr()
+            gname = self.screen.getstr().decode(ENCODING)
             curses.noecho()
 
             if not gname:
@@ -1369,25 +1373,25 @@ def batch(stats):
         s = stats.get()
         for key in sorted(s.keys()):
             values = s[key]
-            print '%-42s%10d%10d' % (key, values[0], values[1])
+            print('%-42s%10d%10d' % (key, values[0], values[1]))
     except KeyboardInterrupt:
         pass
 
 
 def log(stats):
     """Prints statistics as reiterating key block, multiple value blocks."""
-    keys = sorted(stats.get().iterkeys())
+    keys = sorted(stats.get().keys())
 
     def banner():
         for k in keys:
-            print '%s' % k,
-        print
+            print(k, end=' ')
+        print()
 
     def statline():
         s = stats.get()
         for k in keys:
-            print ' %9d' % s[k][1],
-        print
+            print(' %9d' % s[k][1], end=' ')
+        print()
     line = 0
     banner_repeat = 20
     while True: