lib, yang: disable libyang custom user types temporarily

libyang 1.0 introduced a few changes in the user types API, and
these changes made FRR incompatible with libyang 1.x. In order to
ease our migration from libyang 0.x to libyang 1.x, let's disable
our libyang custom user types temporarily so that FRR can work
with both libyang 0.x and libyang 1.x. This should be especially
helpful to the CI systems during the transition. Once the migration
to libyang 1.x is complete, this commit will be reverted.

Disabling our libyang custom user types should have only
minimal performance implications when processing configuration
transactions. The user types infrastructure should be more important
in the future to perform canonization of YANG data values when
necessary.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

Makefile.am

@@ -96,7 +96,6 @@ noinst_LIBRARIES =
 nodist_noinst_DATA =
 lib_LTLIBRARIES =
 module_LTLIBRARIES =
-libyang_plugins_LTLIBRARIES =
 pkginclude_HEADERS =
 nodist_pkginclude_HEADERS =
 dist_examples_DATA =
@@ -111,7 +110,6 @@ vtysh_scan =
 $(AUTOMAKE_DUMMY)install-moduleLTLIBRARIES: install-libLTLIBRARIES
 $(AUTOMAKE_DUMMY)install-binPROGRAMS: install-libLTLIBRARIES
 $(AUTOMAKE_DUMMY)install-sbinPROGRAMS: install-libLTLIBRARIES
-$(AUTOMAKE_DUMMY)install-libyang_pluginsLTLIBRARIES: install-libLTLIBRARIES
 
 include doc/subdir.am
 include doc/user/subdir.am

configure.ac

@@ -1690,24 +1690,6 @@ AC_CHECK_MEMBER([struct lyd_node.priv], [], [
 ], [[#include <libyang/libyang.h>]])
 CFLAGS="$ac_cflags_save"
 
-ac_libs_save="$LIBS"
-LIBS="$LIBS $LIBYANG_LIBS"
-AC_CHECK_FUNC([ly_register_types], [
-  libyang_ext_builtin=true
-  AC_DEFINE([LIBYANG_EXT_BUILTIN], [1], [have ly_register_types()])
-], [
-  libyang_ext_builtin=false
-  AC_MSG_WARN([===== old libyang (before 0.16.74) detected =====])
-  AC_MSG_WARN([The available version of libyang does not seem to support])
-  AC_MSG_WARN([built-in YANG extension modules.  This will cause "make check"])
-  AC_MSG_WARN([to fail and may create installation and version mismatch issues.])
-  AC_MSG_WARN([Support for the old mechanism will be removed at some point.])
-  AC_MSG_WARN([Please update libyang to version 0.16.74 or newer.])
-  AC_MSG_WARN([===== old libyang (before 0.16.74) detected =====])
-])
-AM_CONDITIONAL([LIBYANG_EXT_BUILTIN], [$libyang_ext_builtin])
-LIBS="$ac_libs_save"
-
 dnl ---------------
 dnl configuration rollbacks
 dnl ---------------

lib/yang.c

@@ -617,14 +617,6 @@ static void ly_log_cb(LY_LOG_LEVEL level, const char *msg, const char *path)
 		zlog(priority, "libyang: %s", msg);
 }
 
-#if CONFDATE > 20190401
-CPP_NOTICE("lib/yang: time to remove non-LIBYANG_EXT_BUILTIN support")
-#endif
-
-#ifdef LIBYANG_EXT_BUILTIN
-extern struct lytype_plugin_list frr_user_types[];
-#endif
-
 struct ly_ctx *yang_ctx_new_setup(void)
 {
 	struct ly_ctx *ctx;
@@ -650,54 +642,17 @@ struct ly_ctx *yang_ctx_new_setup(void)
 
 void yang_init(void)
 {
-#ifndef LIBYANG_EXT_BUILTIN
-CPP_NOTICE("lib/yang: deprecated libyang <0.16.74 extension loading in use!")
-	static char ly_plugin_dir[PATH_MAX];
-	const char *const *ly_loaded_plugins;
-	const char *ly_plugin;
-	bool found_ly_frr_types = false;
-
-	/* Tell libyang where to find its plugins. */
-	snprintf(ly_plugin_dir, sizeof(ly_plugin_dir), "%s=%s",
-		 "LIBYANG_USER_TYPES_PLUGINS_DIR", LIBYANG_PLUGINS_PATH);
-	putenv(ly_plugin_dir);
-#endif
-
 	/* Initialize libyang global parameters that affect all containers. */
 	ly_set_log_clb(ly_log_cb, 1);
 	ly_log_options(LY_LOLOG | LY_LOSTORE);
 
-#ifdef LIBYANG_EXT_BUILTIN
-	if (ly_register_types(frr_user_types, "frr_user_types")) {
-		flog_err(EC_LIB_LIBYANG_PLUGIN_LOAD,
-			 "ly_register_types() failed");
-		exit(1);
-	}
-#endif
-
 	/* Initialize libyang container for native models. */
 	ly_native_ctx = yang_ctx_new_setup();
 	if (!ly_native_ctx) {
 		flog_err(EC_LIB_LIBYANG, "%s: ly_ctx_new() failed", __func__);
 		exit(1);
 	}
 
-#ifndef LIBYANG_EXT_BUILTIN
-	/* Detect if the required libyang plugin(s) were loaded successfully. */
-	ly_loaded_plugins = ly_get_loaded_plugins();
-	for (size_t i = 0; (ly_plugin = ly_loaded_plugins[i]); i++) {
-		if (strmatch(ly_plugin, "frr_user_types")) {
-			found_ly_frr_types = true;
-			break;
-		}
-	}
-	if (!found_ly_frr_types) {
-		flog_err(EC_LIB_LIBYANG_PLUGIN_LOAD,
-			 "%s: failed to load frr_user_types.so", __func__);
-		exit(1);
-	}
-#endif
-
 	yang_translator_init();
 }
 

lib/yang_wrappers.c

@@ -817,7 +817,7 @@ void yang_dnode_get_ipv4(struct in_addr *addr, const struct lyd_node *dnode,
 
 	dleaf = (const struct lyd_node_leaf_list *)dnode;
 	assert(dleaf->value_type == LY_TYPE_STRING);
-	memcpy(addr, dleaf->value.ptr, sizeof(*addr));
+	(void)inet_pton(AF_INET, dleaf->value_str, addr);
 }
 
 void yang_get_default_ipv4(struct in_addr *var, const char *xpath_fmt, ...)
@@ -874,7 +874,7 @@ void yang_dnode_get_ipv4p(union prefixptr prefix, const struct lyd_node *dnode,
 
 	dleaf = (const struct lyd_node_leaf_list *)dnode;
 	assert(dleaf->value_type == LY_TYPE_STRING);
-	memcpy(prefix4, dleaf->value.ptr, sizeof(*prefix4));
+	(void)str2prefix_ipv4(dleaf->value_str, prefix4);
 }
 
 void yang_get_default_ipv4p(union prefixptr var, const char *xpath_fmt, ...)
@@ -927,7 +927,7 @@ void yang_dnode_get_ipv6(struct in6_addr *addr, const struct lyd_node *dnode,
 
 	dleaf = (const struct lyd_node_leaf_list *)dnode;
 	assert(dleaf->value_type == LY_TYPE_STRING);
-	memcpy(addr, dleaf->value.ptr, sizeof(*addr));
+	(void)inet_pton(AF_INET6, dleaf->value_str, addr);
 }
 
 void yang_get_default_ipv6(struct in6_addr *var, const char *xpath_fmt, ...)
@@ -984,7 +984,7 @@ void yang_dnode_get_ipv6p(union prefixptr prefix, const struct lyd_node *dnode,
 
 	dleaf = (const struct lyd_node_leaf_list *)dnode;
 	assert(dleaf->value_type == LY_TYPE_STRING);
-	memcpy(prefix6, dleaf->value.ptr, sizeof(*prefix6));
+	(void)str2prefix_ipv6(dleaf->value_str, prefix6);
 }
 
 void yang_get_default_ipv6p(union prefixptr var, const char *xpath_fmt, ...)

yang/libyang_plugins/subdir.am

@@ -2,13 +2,6 @@
 # libyang user types
 #
 
-if LIBYANG_EXT_BUILTIN
-lib_libfrr_la_SOURCES += yang/libyang_plugins/frr_user_types.c
-else
-libyang_plugins_LTLIBRARIES += yang/libyang_plugins/frr_user_types.la
-endif
-
-yang_libyang_plugins_frr_user_types_la_CFLAGS = $(WERROR) $(LIBYANG_CFLAGS)
-yang_libyang_plugins_frr_user_types_la_LDFLAGS = -avoid-version -module -shared -export-dynamic
-yang_libyang_plugins_frr_user_types_la_LIBADD =
-yang_libyang_plugins_frr_user_types_la_SOURCES = yang/libyang_plugins/frr_user_types.c
+# XXX: disable support for libyang custom user types temporarily to facilitate
+# the transition from libyang 0.x to libyang 1.x.
+#lib_libfrr_la_SOURCES += yang/libyang_plugins/frr_user_types.c