python: Implement "vlog/set", "vlog/list" unixctl commands in Python vlog.

This doesn't implement control over log patterns, though.

The change to vlog.man in this commit doesn't have any practical effect
because OVS doesn't come with any Python daemons that have their own
manpages.

Signed-off-by: Ben Pfaff <blp@nicira.com>

python/ovs/vlog.py

@@ -16,6 +16,7 @@
 import datetime
 import logging
 import logging.handlers
+import re
 import socket
 import sys
 
@@ -122,6 +123,10 @@ class Vlog:
 
         ovs.unixctl.command_register("vlog/reopen", "", 0, 0,
                                      Vlog._unixctl_vlog_reopen, None)
+        ovs.unixctl.command_register("vlog/set", "spec", 1, sys.maxint,
+                                     Vlog._unixctl_vlog_set, None)
+        ovs.unixctl.command_register("vlog/list", "", 0, 0,
+                                     Vlog._unixctl_vlog_list, None)
 
     @staticmethod
     def set_level(module, facility, level):
@@ -157,6 +162,43 @@ class Vlog:
             for f in facilities:
                 Vlog.__mfl[m][f] = level
 
+    @staticmethod
+    def set_levels_from_string(s):
+        module = None
+        level = None
+        facility = None
+
+        for word in [w.lower() for w in re.split('[ :]', s)]:
+            if word == "any":
+                pass
+            elif word in FACILITIES:
+                if facility:
+                    return "cannot specify multiple facilities"
+                facility = word
+            elif word in LEVELS:
+                if level:
+                    return "cannot specify multiple levels"
+                level = word
+            elif word in Vlog.__mfl:
+                if module:
+                    return "cannot specify multiple modules"
+                module = word
+            else:
+                return "no facility, level, or module \"%s\"" % word
+
+        Vlog.set_level(module or "any", facility or "any", level or "any")
+
+    @staticmethod
+    def get_levels():
+        lines = ["                 console    syslog    file\n",
+                 "                 -------    ------    ------\n"]
+        lines.extend(sorted(["%-16s  %4s       %4s       %4s\n"
+                             % (m,
+                                Vlog.__mfl[m]["console"],
+                                Vlog.__mfl[m]["syslog"],
+                                Vlog.__mfl[m]["file"]) for m in Vlog.__mfl]))
+        return ''.join(lines)
+
     @staticmethod
     def reopen_log_file():
         """Closes and then attempts to re-open the current log file.  (This is
@@ -177,6 +219,19 @@ class Vlog:
         else:
             conn.reply("Logging to file not configured")
 
+    @staticmethod
+    def _unixctl_vlog_set(conn, argv, unused_aux):
+        for arg in argv:
+            msg = Vlog.set_levels_from_string(arg)
+            if msg:
+                conn.reply(msg)
+                return
+        conn.reply(None)
+
+    @staticmethod
+    def _unixctl_vlog_list(conn, unused_argv, unused_aux):
+        conn.reply(Vlog.get_levels())
+
 def add_args(parser):
     """Adds vlog related options to 'parser', an ArgumentParser object.  The
     resulting arguments parsed by 'parser' should be passed to handle_args."""
@@ -187,7 +242,7 @@ def add_args(parser):
                        " is used if LOG_FILE is omitted.")
     group.add_argument("-v", "--verbose", nargs="*",
                        help="Sets logging levels, see ovs-vswitchd(8)."
-                       "  Defaults to ANY:ANY:dbg.")
+                       "  Defaults to dbg.")
 
 
 def handle_args(args):
@@ -205,23 +260,8 @@ def handle_args(args):
         args.verbose = ["any:any:dbg"]
 
     for verbose in args.verbose:
-        args = verbose.split(':')
-
-        if len(args) >= 3:
-            level = args[2]
-        else:
-            level = "dbg"
-
-        if len(args) >= 2:
-            facility = args[1]
-        else:
-            facility = "any"
-
-        if len(args) >= 1:
-            module = args[0]
-        else:
-            module = "any"
-
-        Vlog.set_level(module, facility, level)
+        msg = Vlog.set_levels_from_string(verbose)
+        if msg:
+            ovs.util.ovs_fatal(0, "processing \"%s\": %s" % (verbose, msg))
 
     Vlog.init(log_file)