[MPLS] Minor tweaks to VS for MPLS support for CRM polling of MPLS In-segments and NHs.

Author: qbdwlr

meta/Meta.cpp

@@ -1786,8 +1786,11 @@ sai_status_t Meta::objectTypeGetAvailability(
     PARAMETER_CHECK_OID_OBJECT_TYPE(switchId, SAI_OBJECT_TYPE_SWITCH);
     PARAMETER_CHECK_OID_EXISTS(switchId, SAI_OBJECT_TYPE_SWITCH);
     PARAMETER_CHECK_OBJECT_TYPE_VALID(objectType);
-    PARAMETER_CHECK_POSITIVE(attrCount);
-    PARAMETER_CHECK_IF_NOT_NULL(attrList);
+    // When checking availability of a resource solely based on OBJECT_TYPE, attrCount is 0
+    if (attrCount)
+    {
+        PARAMETER_CHECK_IF_NOT_NULL(attrList);
+    }
     PARAMETER_CHECK_IF_NOT_NULL(count);
 
     auto info = sai_metadata_get_object_type_info(objectType);

tests/aspell.en.pws

@@ -48,6 +48,7 @@ cout
 cpp
 cpu
 CreateObject
+CRM
 currentObj
 currentObject
 currentView

vslib/src/VirtualSwitchSaiInterface.cpp

@@ -3,6 +3,8 @@
 #include "../../lib/inc/PerformanceIntervalTimer.h"
 
 #include "swss/logger.h"
+#include "swss/exec.h"
+#include "swss/converter.h"
 
 #include "meta/sai_serialize.h"
 #include "meta/SaiAttributeList.h"
@@ -817,6 +819,26 @@ sai_status_t VirtualSwitchSaiInterface::objectTypeGetAvailability(
         *count = 3;
         return SAI_STATUS_SUCCESS;
     }
+    // MPLS Inseg and MPLS NH CRM use sai_object_type_get_availability() API.
+    else if ((objectType == SAI_OBJECT_TYPE_INSEG_ENTRY) ||
+             ((objectType == SAI_OBJECT_TYPE_NEXT_HOP) &&
+              (attrCount == 1) && attrList &&
+              (attrList[0].id == SAI_NEXT_HOP_ATTR_TYPE) &&
+              (attrList[0].value.s32 == SAI_NEXT_HOP_TYPE_MPLS)))
+    {
+        std::string cmd_str("sysctl net.mpls.platform_labels");
+        std::string ret_str;
+        *count = 1000;
+        if (!swss::exec(cmd_str, ret_str))
+        {
+            std::string match("net.mpls.platform_labels = ");
+            if (ret_str.find(match) != std::string::npos)
+            {
+                *count = std::stoul(ret_str.substr(match.length()).c_str());
+            }
+        }
+        return SAI_STATUS_SUCCESS;
+    }
 
     return SAI_STATUS_NOT_SUPPORTED;
 }