Fix detect chroot function.

pym/cl_vars_share.py

@@ -510,20 +510,10 @@ class varsShare:
             if reRes:
                 return reRes.group()
 
-    reChroot = re.compile("^(?:_=.*bin/chroot|CHROOT=on)$",re.S)
-
     def isChroot(self,pid):
-        """Recursive detect chroot mode"""
-        if not os.access('/proc/%d/environ'%pid,R_OK):
+        """Detect chroot mode by different mountinfo"""
+        if not os.access('/proc/self/mountinfo',R_OK) or \
+            not os.access('/proc/1/mountinfo',R_OK):
             return False
-        if filter(self.reChroot.match,
-                  open('/proc/%d/environ'%pid,'r').read().split('\x00')):
-            return True
-        else:
-            ppid = filter(lambda x:x.startswith('PPid:'),
-                              open('/proc/%d/status'%pid,'r').readlines())[0]
-            ppid = int(ppid.strip().partition('\t')[2])
-            if ppid == 0:
-                return False
-            else:
-                return self.isChroot(ppid)
+        return open('/proc/1/mountinfo','r').read() != \
+               open('/proc/self/mountinfo','r').read()