snmp plugin: Keep track of signedness of ASN values.

[collectd.git] / src / snmp.c

diff --git a/src/snmp.c b/src/snmp.c
index 693cd89..5c6cce2 100644 (file)
--- a/src/snmp.c
+++ b/src/snmp.c
@@ -655,8 +655,9 @@ static int csnmp_config_add_host (oconfig_item_t *ci)
   if (hd->interval != 0)
     cb_interval.tv_sec = (time_t) hd->interval;
 
-  status = plugin_register_complex_read (cb_name, csnmp_read_host,
-      /* interval = */ &cb_interval, /* user_data = */ &cb_data);
+  status = plugin_register_complex_read (/* group = */ NULL, cb_name,
+      csnmp_read_host, /* interval = */ &cb_interval,
+      /* user_data = */ &cb_data);
   if (status != 0)
   {
     ERROR ("snmp plugin: Registering complex read function failed.");
@@ -726,7 +727,9 @@ static value_t csnmp_value_list_to_value (struct variable_list *vl, int type,
   value_t ret;
   uint64_t tmp_unsigned = 0;
   int64_t tmp_signed = 0;
-  int defined = 1;
+  _Bool defined = 1;
+  /* Set to true when the original SNMP type appears to have been signed. */
+  _Bool prefer_signed = 0;
 
   if ((vl->type == ASN_INTEGER)
       || (vl->type == ASN_UINTEGER)
@@ -738,7 +741,12 @@ static value_t csnmp_value_list_to_value (struct variable_list *vl, int type,
   {
     tmp_unsigned = (uint32_t) *vl->val.integer;
     tmp_signed = (int32_t) *vl->val.integer;
-    DEBUG ("snmp plugin: Parsed int32 value is %"PRIi64".", tmp_signed);
+
+    if ((vl->type == ASN_INTEGER)
+        || (vl->type == ASN_GAUGE))
+      prefer_signed = 1;
+
+    DEBUG ("snmp plugin: Parsed int32 value is %"PRIu64".", tmp_unsigned);
   }
   else if (vl->type == ASN_COUNTER64)
   {
@@ -827,14 +835,24 @@ static value_t csnmp_value_list_to_value (struct variable_list *vl, int type,
   }
   else if (type == DS_TYPE_GAUGE)
   {
-    ret.gauge = NAN;
-    if (defined != 0)
+    if (!defined)
+      ret.gauge = NAN;
+    else if (prefer_signed)
       ret.gauge = (scale * tmp_signed) + shift;
+    else
+      ret.gauge = (scale * tmp_unsigned) + shift;
   }
   else if (type == DS_TYPE_DERIVE)
-    ret.derive = (derive_t) tmp_signed;
+  {
+    if (prefer_signed)
+      ret.derive = (derive_t) tmp_signed;
+    else
+      ret.derive = (derive_t) tmp_unsigned;
+  }
   else if (type == DS_TYPE_ABSOLUTE)
+  {
     ret.absolute = (absolute_t) tmp_unsigned;
+  }
   else
   {
     ERROR ("snmp plugin: csnmp_value_list_to_value: Unknown data source "
@@ -965,7 +983,7 @@ static int csnmp_strvbcopy (char *dst, /* {{{ */
   for (i = 0; i < num_chars; i++)
   {
     /* Check for control characters. */
-    if ((src[i] >= 0) && (src[i] < 32))
+    if ((unsigned char)src[i] < 32)
       return (csnmp_strvbcopy_hexstring (dst, vb, dst_size));
     dst[i] = src[i];
   }