Add check for UTF-8 encoding (#131) (#135)

Also moved workaround from #117 to common place - gdbinit.py

gdbinit.py

@@ -4,6 +4,8 @@ from __future__ import print_function
 from __future__ import unicode_literals
 
 import sys
+import six
+import locale
 from os import path
 
 directory, file = path.split(__file__)
@@ -12,4 +14,22 @@ directory       = path.abspath(directory)
 
 sys.path.append(directory)
 
+# this is an unconventional workaround to
+# support unicode printing for python2
+# https://github.com/pwndbg/pwndbg/issues/117
+# on python3 it warns if the user has different
+# encoding than utf-8
+encoding = locale.getpreferredencoding()
+if six.PY2:
+    reload(sys)
+    sys.setdefaultencoding('utf-8')
+
+elif encoding != 'UTF-8':
+    print('******')
+    print('Your encoding ({}) is different than UTF-8. pwndbg might not work properly.'.format(encoding))
+    print('You might try launching gdb with:')
+    print('    LC_ALL=en_US.UTF-8 PYTHONIOENCODING=UTF-8 gdb')
+    print('Make sure that en_US.UTF-8 is activated in /etc/locale.gen and you called locale-gen')
+    print('******')
+
 import pwndbg # isort:skip

pwndbg/__init__.py

@@ -8,7 +8,6 @@ from __future__ import unicode_literals
 import sys
 
 import gdb
-import six
 
 import pwndbg.android
 import pwndbg.arch
@@ -73,14 +72,6 @@ try:
 except:
     pass
 
-# this is an unconventional workaround to
-# support unicode printing for python2
-# https://github.com/pwndbg/pwndbg/issues/117
-if six.PY2:
-    reload(sys)
-    sys.setdefaultencoding('utf-8')
-
-
 __all__ = [
 'arch',
 'auxv',