lib: use libyang functions if they are present

Add configure.ac tests for libyang functions, if not present supply the
functionality ourselves in yang.[ch]

Signed-off-by: Christian Hopps <chopps@labn.net>

configure.ac

@@ -1968,6 +1968,13 @@ AC_CHECK_MEMBER([struct lyd_node.priv], [], [
     Instructions for this are included in the build documentation for your platform at http://docs.frrouting.org/projects/dev-guide/en/latest/building.html])
   ])
 ], [[#include <libyang/libyang.h>]])
+
+AC_CHECK_LIB([yang],[lyd_find_xpath3],[],[AC_MSG_ERROR([m4_normalize([
+libyang missing lyd_find_xpath3])])])
+dnl -- don't add lyd_new_list3 to this list unless bug is fixed upstream
+dnl -- https://github.com/CESNET/libyang/issues/2149
+AC_CHECK_FUNCS([ly_strerrcode ly_strvecode lyd_trim_xpath])
+
 CFLAGS="$ac_cflags_save"
 
 dnl ---------------

lib/northbound_oper.c

@@ -1409,11 +1409,8 @@ static enum nb_error __walk(struct nb_op_yield_state *ys, bool is_resume)
 			 */
 
 			if (!node) {
-				/* NOTE: can also use lyd_new_list2 here when available */
 				err = yang_lyd_new_list(ni[-1].inner, sib,
-							&ni->keys,
+							&ni->keys, &node);
-							(struct lyd_node_inner *
-								 *)&node);
 				if (err) {
 					darr_pop(ys->node_infos);
 					ret = NB_ERR_RESOURCE;

lib/vty.c

@@ -3688,88 +3688,9 @@ static void vty_out_yang_error(struct vty *vty, LYD_FORMAT format,
 	else if (ei->level == LY_LLWRN)
 		severity = "warning";
 
-	switch (ei->no) {
+	ecode = yang_ly_strerrcode(err);
-	case LY_SUCCESS:
+	if (err == LY_EVALID && ei->vecode != LYVE_SUCCESS)
-		ecode = "ok";
+		evalid = yang_ly_strvecode(ei->vecode);
-		break;
-	case LY_EMEM:
-		ecode = "out of memory";
-		break;
-	case LY_ESYS:
-		ecode = "system error";
-		break;
-	case LY_EINVAL:
-		ecode = "invalid value given";
-		break;
-	case LY_EEXIST:
-		ecode = "item exists";
-		break;
-	case LY_ENOTFOUND:
-		ecode = "item not found";
-		break;
-	case LY_EINT:
-		ecode = "operation interrupted";
-		break;
-	case LY_EVALID:
-		ecode = "validation failed";
-		break;
-	case LY_EDENIED:
-		ecode = "access denied";
-		break;
-	case LY_EINCOMPLETE:
-		ecode = "incomplete";
-		break;
-	case LY_ERECOMPILE:
-		ecode = "compile error";
-		break;
-	case LY_ENOT:
-		ecode = "not";
-		break;
-	default:
-	case LY_EPLUGIN:
-	case LY_EOTHER:
-		ecode = "other";
-		break;
-	}
-
-	if (err == LY_EVALID) {
-		switch (ei->vecode) {
-		case LYVE_SUCCESS:
-			evalid = NULL;
-			break;
-		case LYVE_SYNTAX:
-			evalid = "syntax";
-			break;
-		case LYVE_SYNTAX_YANG:
-			evalid = "yang-syntax";
-			break;
-		case LYVE_SYNTAX_YIN:
-			evalid = "yin-syntax";
-			break;
-		case LYVE_REFERENCE:
-			evalid = "reference";
-			break;
-		case LYVE_XPATH:
-			evalid = "xpath";
-			break;
-		case LYVE_SEMANTICS:
-			evalid = "semantics";
-			break;
-		case LYVE_SYNTAX_XML:
-			evalid = "xml-syntax";
-			break;
-		case LYVE_SYNTAX_JSON:
-			evalid = "json-syntax";
-			break;
-		case LYVE_DATA:
-			evalid = "data";
-			break;
-		default:
-		case LYVE_OTHER:
-			evalid = "other";
-			break;
-		}
-	}
 
 	switch (format) {
 	case LYD_XML:

lib/yang.c

@@ -999,86 +999,109 @@ int yang_get_node_keys(struct lyd_node *node, struct yang_list_keys *keys)
 	return NB_OK;
 }
 
+/*
+ * ------------------------
+ * Libyang Future Functions
+ * ------------------------
+ *
+ * All these functions are implemented in libyang versions (perhaps unreleased)
+ * beyond what we require currently so we must supply the functionality.
+ */
+
+/*
+ * Safe to remove after libyang v2.1.xxx is required (.144 has a bug so
+ * something > .144) https://github.com/CESNET/libyang/issues/2149
+ */
 LY_ERR yang_lyd_new_list(struct lyd_node_inner *parent,
 			 const struct lysc_node *snode,
 			 const struct yang_list_keys *list_keys,
-			 struct lyd_node_inner **node)
+			 struct lyd_node **node)
 {
+#if defined(HAVE_LYD_NEW_LIST3) && 0
+	LY_ERR err;
+	const char *keys[LIST_MAXKEYS];
+
+	assert(list_keys->num <= LIST_MAXKEYS);
+	for (int i = 0; i < list_keys->num; i++)
+		keys[i] = list_keys->key[i];
+
+	err = lyd_new_list3(&parent->node, snode->module, snode->name, keys,
+			    NULL, 0, node);
+	return err;
+#else
 	struct lyd_node *pnode = &parent->node;
-	struct lyd_node **nodepp = (struct lyd_node **)node;
 	const char(*keys)[LIST_MAXKEYLEN] = list_keys->key;
 
-	/*
+	assert(list_keys->num <= 8);
-	 * When
-	 * https://github.com/CESNET/libyang/commit/2c1e327c7c2dd3ba12d466a4ebcf62c1c44116c4
-	 * is released in libyang we should add a configure.ac check for the
-	 * lyd_new_list3 function and use it here.
-	 */
 	switch (list_keys->num) {
 	case 0:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp);
+				    node);
 	case 1:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0]);
+				    node, keys[0]);
 	case 2:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0], keys[1]);
+				    node, keys[0], keys[1]);
 	case 3:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0], keys[1], keys[2]);
+				    node, keys[0], keys[1], keys[2]);
 	case 4:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0], keys[1], keys[2], keys[3]);
+				    node, keys[0], keys[1], keys[2], keys[3]);
 	case 5:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0], keys[1], keys[2], keys[3],
+				    node, keys[0], keys[1], keys[2], keys[3],
 				    keys[4]);
 	case 6:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0], keys[1], keys[2], keys[3],
+				    node, keys[0], keys[1], keys[2], keys[3],
 				    keys[4], keys[5]);
 	case 7:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0], keys[1], keys[2], keys[3],
+				    node, keys[0], keys[1], keys[2], keys[3],
 				    keys[4], keys[5], keys[6]);
 	case 8:
 		return lyd_new_list(pnode, snode->module, snode->name, false,
-				    nodepp, keys[0], keys[1], keys[2], keys[3],
+				    node, keys[0], keys[1], keys[2], keys[3],
 				    keys[4], keys[5], keys[6], keys[7]);
 	}
 	_Static_assert(LIST_MAXKEYS == 8, "max key mismatch in switch unroll");
 	/*NOTREACHED*/
 	return LY_EINVAL;
+#endif
 }
 
 
-int yang_trim_tree(struct lyd_node *root, const char *xpath)
+/*
+ * Safe to remove after libyang v2.1.144 is required
+ */
+LY_ERR yang_lyd_trim_xpath(struct lyd_node **root, const char *xpath)
 {
-	enum nb_error ret = NB_OK;
 	LY_ERR err;
-#if 0
+#ifdef HAVE_LYD_TRIM_XPATH
-	err = lyd_trim_xpath(&root, xpath, NULL);
+	err = lyd_trim_xpath(root, xpath, NULL);
 	if (err) {
 		flog_err_sys(EC_LIB_LIBYANG,
-			     "cannot obtain specific result for xpath \"%s\"",
+			     "cannot obtain specific result for xpath \"%s\": %s",
-			     xpath);
+			     xpath, yang_ly_strerrcode(err));
-		return NB_ERR;
+		return err;
 	}
-	return NB_OK;
+	return LY_SUCCESS;
 #else
 	struct lyd_node *node;
 	struct lyd_node **remove = NULL;
 	struct ly_set *set = NULL;
 	uint32_t i;
 
-	err = lyd_find_xpath3(NULL, root, xpath, NULL, &set);
+	*root = lyd_first_sibling(*root);
+
+	err = lyd_find_xpath3(NULL, *root, xpath, NULL, &set);
 	if (err) {
 		flog_err_sys(EC_LIB_LIBYANG,
-			     "cannot obtain specific result for xpath \"%s\"",
+			     "cannot obtain specific result for xpath \"%s\": %s",
-			     xpath);
+			     xpath, yang_ly_strerrcode(err));
-		ret = NB_ERR;
+		return err;
-		goto done;
 	}
 	/*
 	 * Mark keepers and sweep deleting non-keepers.
@@ -1100,7 +1123,7 @@ int yang_trim_tree(struct lyd_node *root, const char *xpath)
 	}
 
 	darr_ensure_cap(remove, 128);
-	LYD_TREE_DFS_BEGIN (root, node) {
+	LYD_TREE_DFS_BEGIN (*root, node) {
 		/*
 		 * If this is a direct matching node then include it's subtree
 		 * which won't be marked and would otherwise be removed.
@@ -1108,19 +1131,100 @@ int yang_trim_tree(struct lyd_node *root, const char *xpath)
 		if (node->priv == (void *)2)
 			LYD_TREE_DFS_continue = 1;
 		else if (!node->priv) {
-			LYD_TREE_DFS_continue = 1;
 			*darr_append(remove) = node;
+			LYD_TREE_DFS_continue = 1;
 		}
-		LYD_TREE_DFS_END(root, node);
+		LYD_TREE_DFS_END(*root, node);
 	}
-	darr_foreach_i (remove, i)
+	darr_foreach_i (remove, i) {
+		if (remove[i] == *root)
+			*root = (*root)->next;
 		lyd_free_tree(remove[i]);
+	}
 	darr_free(remove);
 
-done:
 	if (set)
 		ly_set_free(set, NULL);
 
-	return ret;
+	return LY_SUCCESS;
+#endif
+}
+
+/*
+ * Safe to remove after libyang v2.1.128 is required
+ */
+const char *yang_ly_strerrcode(LY_ERR err)
+{
+#ifdef HAVE_LY_STRERRCODE
+	return ly_strerrcode(err);
+#else
+	switch (err) {
+	case LY_SUCCESS:
+		return "ok";
+	case LY_EMEM:
+		return "out of memory";
+	case LY_ESYS:
+		return "system error";
+	case LY_EINVAL:
+		return "invalid value given";
+	case LY_EEXIST:
+		return "item exists";
+	case LY_ENOTFOUND:
+		return "item not found";
+	case LY_EINT:
+		return "operation interrupted";
+	case LY_EVALID:
+		return "validation failed";
+	case LY_EDENIED:
+		return "access denied";
+	case LY_EINCOMPLETE:
+		return "incomplete";
+	case LY_ERECOMPILE:
+		return "compile error";
+	case LY_ENOT:
+		return "not";
+	case LY_EPLUGIN:
+	case LY_EOTHER:
+		return "other";
+	default:
+		return "unknown";
+	}
+#endif
+}
+
+/*
+ * Safe to remove after libyang v2.1.128 is required
+ */
+const char *yang_ly_strvecode(LY_VECODE vecode)
+{
+#ifdef HAVE_LY_STRVECODE
+	return ly_strvecode(vecode);
+#else
+	switch (vecode) {
+	case LYVE_SUCCESS:
+		return "";
+	case LYVE_SYNTAX:
+		return "syntax";
+	case LYVE_SYNTAX_YANG:
+		return "yang-syntax";
+	case LYVE_SYNTAX_YIN:
+		return "yin-syntax";
+	case LYVE_REFERENCE:
+		return "reference";
+	case LYVE_XPATH:
+		return "xpath";
+	case LYVE_SEMANTICS:
+		return "semantics";
+	case LYVE_SYNTAX_XML:
+		return "xml-syntax";
+	case LYVE_SYNTAX_JSON:
+		return "json-syntax";
+	case LYVE_DATA:
+		return "data";
+	case LYVE_OTHER:
+		return "other";
+	default:
+		return "unknown";
+	}
 #endif
 }

lib/yang.h

@@ -719,11 +719,6 @@ extern int yang_get_key_preds(char *s, const struct lysc_node *snode,
 /* Get YANG keys from an existing dnode */
 extern int yang_get_node_keys(struct lyd_node *node, struct yang_list_keys *keys);
 
-/* Create a new list lyd_node using `yang_list_keys` */
-extern LY_ERR yang_lyd_new_list(struct lyd_node_inner *parent,
-				const struct lysc_node *snode,
-				const struct yang_list_keys *keys,
-				struct lyd_node_inner **node);
 /**
  * yang_resolve_snodes() - Resolve an XPath to matching schema nodes.
  * @ly_ctx: libyang context to operate on.
@@ -744,14 +739,16 @@ extern LY_ERR yang_lyd_new_list(struct lyd_node_inner *parent,
 extern LY_ERR yang_resolve_snode_xpath(struct ly_ctx *ly_ctx, const char *xpath,
 				       struct lysc_node ***snodes, bool *simple);
 
-/**
+/*
- * yang_trim_tree() - trim the data tree to the given xpath
+ * Libyang future functions
- * @root: the data tree
- * @xpath: the xpath to trim @root to.
- *
- * Return: enum nb_error..
  */
-extern int yang_trim_tree(struct lyd_node *root, const char *xpath);
+extern const char *yang_ly_strerrcode(LY_ERR err);
+extern const char *yang_ly_strvecode(LY_VECODE vecode);
+extern LY_ERR yang_lyd_new_list(struct lyd_node_inner *parent,
+				const struct lysc_node *snode,
+				const struct yang_list_keys *keys,
+				struct lyd_node **nodes);
+extern LY_ERR yang_lyd_trim_xpath(struct lyd_node **rootp, const char *xpath);
 
 #ifdef __cplusplus
 }

mgmtd/mgmt_txn.c

@@ -1278,8 +1278,9 @@ static int txn_get_tree_data_done(struct mgmt_txn_ctx *txn,
 		/*
 		 * We have a complex query so Filter results by the xpath query.
 		 */
-		ret = yang_trim_tree(get_tree->client_results,
+		if (yang_lyd_trim_xpath(&get_tree->client_results,
-				     txn_req->req.get_tree->xpath);
+					txn_req->req.get_tree->xpath))
+			ret = NB_ERR;
 	}
 
 	if (ret == NB_OK)