[gentoo-portage-dev] [PATCH] _selinux.setexec: improve failure message (525726)

[Zac Medico]

From: Sven Vermeulen <swift@g.o>

This converts "OSError: [Errno 22] Invalid argument" into a more
meaningful error message that is to designed to guide users in the
right direction. Also, add an import that was missing for the "sys"
module, since is referenced in the error paths of many functions in
this module.

X-Gentoo-Bug: 525726
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=525726
---
 pym/portage/_selinux.py | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/pym/portage/_selinux.py b/pym/portage/_selinux.py
index 2a7194c..c5e8b2c 100644
--- a/pym/portage/_selinux.py
+++ b/pym/portage/_selinux.py
@@ -5,6 +5,7 @@
 # the whole _selinux module itself will be wrapped.
 import os
 import shutil
+import sys
 
 import portage
 from portage import _encodings
@@ -77,7 +78,18 @@ def settype(newtype):
 
 def setexec(ctx="\n"):
 	ctx = _native_string(ctx, encoding=_encodings['content'], errors='strict')
-	if selinux.setexeccon(ctx) < 0:
+	rc = 0
+	try:
+		rc = selinux.setexeccon(ctx)
+	except OSError:
+		msg = _("Failed to set new SELinux execution context. " + \
+			"Is your current SELinux context allowed to run Portage?")
+		if selinux.security_getenforce() == 1:
+			raise OSError(msg)
+		else:
+			portage.writemsg("!!! %s\n" % msg, noiselevel=-1)
+
+	if rc < 0:
 		if sys.hexversion < 0x3000000:
 			ctx = _unicode_decode(ctx, encoding=_encodings['content'], errors='replace')
 		if selinux.security_getenforce() == 1:
-- 
2.0.4