Collectd patch to collect cpu average on linux

I'm using collectd to collectd data at work -> http://www.collectd.org The cpu plugin don't collectd average cpu usage, I have create a patch to work this around. Here it is

diff -Nurp collectd-5.0.1/src/cpu.c collectd-5.0.1-new/src/cpu.c
--- collectd-5.0.1/src/cpu.c 2011-10-14 17:49:49.000000000 -0300
+++ collectd-5.0.1-new/src/cpu.c 2012-01-03 17:48:22.000000000 -0200
@@ -252,7 +252,11 @@ static void submit (int cpu_num, const c
  vl.values_len = 1;
  sstrncpy (vl.host, hostname_g, sizeof (vl.host));
  sstrncpy (vl.plugin, "cpu", sizeof (vl.plugin));
- ssnprintf (vl.plugin_instance, sizeof (vl.plugin_instance),
+        if (cpu_num < 0)
+                ssnprintf (vl.plugin_instance, sizeof (vl.plugin_instance),
+   "avg");
+        else
+                ssnprintf (vl.plugin_instance, sizeof (vl.plugin_instance),
    "%i", cpu_num);
  sstrncpy (vl.type, "cpu", sizeof (vl.type));
  sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
@@ -359,6 +363,7 @@ static int cpu_read (void)
 
  char *fields[9];
  int numfields;
+        int coren = sysconf(_SC_NPROCESSORS_ONLN); /* number of cores */
 
  if ((fh = fopen ("/proc/stat", "r")) == NULL)
  {
@@ -372,18 +377,24 @@ static int cpu_read (void)
  {
   if (strncmp (buf, "cpu", 3))
    continue;
-  if ((buf[3] < '0') || (buf[3] > '9'))
-   continue;
 
   numfields = strsplit (buf, fields, 9);
   if (numfields < 5)
    continue;
 
-  cpu = atoi (fields[0] + 3);
-  user = atoll (fields[1]);
-  nice = atoll (fields[2]);
-  syst = atoll (fields[3]);
-  idle = atoll (fields[4]);
+                if (!isdigit(fields[0][3])) {
+                        cpu = -1;
+                        user = atoll (fields[1]) / coren;
+                        nice = atoll (fields[2]) / coren;
+                        syst = atoll (fields[3]) / coren;
+                        idle = atoll (fields[4]) / coren;
+                } else { 
+          cpu = atoi (fields[0] + 3);
+                        user = atoll (fields[1]);
+                        nice = atoll (fields[2]);
+                        syst = atoll (fields[3]);
+                        idle = atoll (fields[4]);
+                }
 
   submit (cpu, "user", user);
   submit (cpu, "nice", nice);
@@ -392,9 +403,15 @@ static int cpu_read (void)
 
   if (numfields >= 8)
   {
-   wait = atoll (fields[5]);
-   intr = atoll (fields[6]);
-   sitr = atoll (fields[7]);
+                        if (cpu < 0) {
+                                wait = atoll (fields[5]) / coren;
+                                intr = atoll (fields[6]) / coren;
+                                sitr = atoll (fields[7]) / coren;
+                        } else {
+                                wait = atoll (fields[5]);
+                                intr = atoll (fields[6]);
+                                sitr = atoll (fields[7]);
+                        }
 
    submit (cpu, "wait", wait);
    submit (cpu, "interrupt", intr);