Optimization: Added mountpoint cache as yang flag YANG_FLAG_MTPOINT_POTENTIAL

Filter state-data w xpath

CHANGELOG.md

@@ -13,7 +13,12 @@ Expected: February 2024
 
 ### Minor features
 
+* Optimization:
+  * Added mountpoint cache as yang flag `YANG_FLAG_MTPOINT_POTENTIAL`
+  * Optimized `yang_find`, especially namespace lookup
+  * Filtered state data if not match xpath
 * Added reference count for shared yang-specs (schema mounts)
+  * Allowed for sharing yspec+modules between several mountpoints
 
 ### Corrected Bugs
 

apps/backend/backend_plugin.c

@@ -393,10 +393,12 @@ clixon_plugin_statedata_all(clicon_handle   h,
         /* XXX: only for state data and according to with-defaults setting */
         if (xml_defaults_nopresence(x, 2) < 0)
             goto done;
-        if ((ret = netconf_trymerge(x, yspec, xret)) < 0)
-            goto done;
-        if (ret == 0)
-            goto fail;
+        if (xpath_first(x, nsc, "%s", xpath) != NULL){
+            if ((ret = netconf_trymerge(x, yspec, xret)) < 0)
+                goto done;
+            if (ret == 0)
+                goto fail;
+        }
         if (x){
             xml_free(x);
             x = NULL;

lib/clixon/clixon_yang.h

@@ -83,7 +83,14 @@
                                       *     leaf z;
                                       *  }
                                       */
-#define YANG_FLAG_MOUNTPOINT 0x100  /* Mark node as ACTUAL populated mount-point
+#define YANG_FLAG_MTPOINT_POTENTIAL 0x100 /* Mark node as POTENTIAL mount-point, ie it fulfils:
+                                      * - is CONTAINER or LIST, AND
+                                      * - has YANG schema mount "mount-point" as child element, AND
+                                      * - the extension label matches y (see note below)
+                                      * Set by ys_populate2
+                                      * Read by yang_schema_mount_point
+                                      */
+#define YANG_FLAG_MOUNTPOINT   0x200 /* Mark node as ACTUAL populated mount-point
                                       * Set by yang_mount_set 
                                       * Read by ys_free1
                                       */

lib/clixon/clixon_yang_schema_mount.h

@@ -54,6 +54,7 @@
 /*
  * Prototypes
  */
+int yang_schema_mount_point0(yang_stmt *y);
 int yang_schema_mount_point(yang_stmt *y);
 int yang_mount_get(yang_stmt *yu, char *xpath, yang_stmt **yspec);
 int yang_mount_set(yang_stmt *yu, char *xpath, yang_stmt *yspec);

lib/src/clixon_yang.c

@@ -3017,6 +3017,7 @@ ys_populate2(yang_stmt    *ys,
 {
     int           retval = -1;
     clicon_handle h = (clicon_handle)arg;
+    int           ret;
 
     switch(ys->ys_keyword){
     case Y_LEAF:
@@ -3033,6 +3034,11 @@ ys_populate2(yang_stmt    *ys,
     default:
         break;
     }
+    /* RFC 8525 Yang schema mount  flag for optimization */
+    if ((ret = yang_schema_mount_point0(ys)) < 0)
+        goto done;
+    if (ret == 1)
+        yang_flag_set(ys, YANG_FLAG_MTPOINT_POTENTIAL);
     retval = 0;
   done:
     return retval;

lib/src/clixon_yang_internal.h

@@ -98,7 +98,7 @@ struct yang_stmt{
                                         Y_TYPE & identity: store all derived 
                                            types as <module>:<id> list
                                         Y_UNIQUE: vector of descendant schema node ids
-                                        Y_EXTENSION: vector of instantiated UNKNOWNSo
+                                        Y_EXTENSION: vector of instantiated UNKNOWNS
                                         Y_UNKNOWN: app-dep: yang-mount-points
                                      */
     int                ys_ref;       /* Reference count for free, only YS_SPEC */

lib/src/clixon_yang_schema_mount.c

@@ -102,7 +102,7 @@
  * @note That this may be a restriction on the usage of "label". The RFC is somewhat unclear.
  */
 int
-yang_schema_mount_point(yang_stmt *y)
+yang_schema_mount_point0(yang_stmt *y)
 {
     int           retval = -1;
     enum rfc_6020 keyw;
@@ -137,6 +137,14 @@ yang_schema_mount_point(yang_stmt *y)
     goto done;
 }
 
+/*! Cached variant of yang_schema_mount_point
+ */
+int
+yang_schema_mount_point(yang_stmt *y)
+{
+    return yang_flag_get(y, YANG_FLAG_MTPOINT_POTENTIAL) ? 1 : 0;
+}
+
 /*! Get yangspec mount-point
  *
  * @param[in]  y     Yang container/list containing unknown node
@@ -431,6 +439,7 @@ find_schema_mounts(cxobj *x,
  *   "ietf-yang-schema-mount" modules in the mounted schema and specifying
  *   the schemas in exactly the same way as the top-level schema.
  * Alt: see snmp_yang2xml to get instances instead of brute force traverse of whole tree
+ * @note: Mountpoints must exist in xret on entry
  */
 static int
 yang_schema_mount_statedata_yanglib(clicon_handle h,
@@ -494,7 +503,7 @@ yang_schema_mount_statedata_yanglib(clicon_handle h,
  *
  * @param[in]     h       Clixon handle
  * @param[in]     yspec   Yang spec
- * @param[in]     xpath   XML Xpath
+ * @param[in]     xpath   XML XPath
  * @param[in]     nsc     XML Namespace context for xpath
  * @param[in,out] xret    Existing XML tree, merge x into this
  * @param[out]    xerr    XML error tree, if retval = 0
@@ -556,10 +565,12 @@ yang_schema_mount_statedata(clicon_handle h,
             goto done;
         if (ret == 0)
             goto fail;
-        if ((ret = netconf_trymerge(x1, yspec, xret)) < 0)
-            goto done;
-        if (ret == 0)
-            goto fail;
+        if (xpath_first(x1, nsc, "%s", xpath) != NULL){
+            if ((ret = netconf_trymerge(x1, yspec, xret)) < 0)
+                goto done;
+            if (ret == 0)
+                goto fail;
+        }
     }
     /* Find mount-points and return yang-library state */
     if (yang_schema_mount_statedata_yanglib(h, xpath, nsc, xret, xerr) < 0)