* Added clicon_handle as parameter to all validate functions

* Added libxml2 XSD regexp mode as alternative to posix translation
* Added `CLICON_YANG_REGEXP` option with possible values libxml2 and posix

CHANGELOG.md

@@ -54,6 +54,8 @@
 	
 ### API changes on existing features (you may need to change your code)
 
+* Added clicon_handle as parameter to all validate functions
+  * Just add `clixon_handle h` to all calls.
 * Clixon transaction mechanism has changed which may affect your backend plugin callbacks:
   * Validate-only transactions are terminated by an `end` or `abort` callback. Now all started transactions are terminated either by an `end` or `abort` without exceptions
     * Validate-only transactions used to be terminated by `complete`
@@ -140,11 +142,13 @@
 ### Minor changes
 
 * Regexp improvements
+  * Added libxml2 XSD regexp mode as alternative to posix translation
   * Better compliance with XSD regexps (when transforming to Posix regexps)
     * Added `\p{L}` and `\p{N}`
     * Added escaping of `$`
+  * Added `CLICON_YANG_REGEXP`option with possible values libxml2 and posix
   * Added clixon_util_regexp utility function
-  * Added regexp [test/test_pattern.sh]
+  * Added regexp test [test/test_pattern.sh]
 * Yang state get improvements
   * Integrated state and config into same tree on retrieval, not separate trees
   * Added cli functions `cli_show_config_state()` and `cli_show_auto_state()` for showing combined config and state info.

apps/backend/backend_client.c

@@ -470,7 +470,7 @@ from_client_edit_config(clicon_handle h,
 	    goto ok;
 	}
 	/* xmldb_put (difflist handling) requires list keys */
-	if ((ret = xml_yang_validate_list_key_only(xc, cbret)) < 0)
+	if ((ret = xml_yang_validate_list_key_only(h, xc, cbret)) < 0)
 	    goto done;
 	if (ret == 0)
 	    goto ok;
@@ -1147,7 +1147,7 @@ from_client_msg(clicon_handle        h,
      * maybe not necessary since it should be */
     if (xml_spec_populate_rpc(h, x, yspec) < 0)
     	goto done;
-    if ((ret = xml_yang_validate_rpc(x, cbret)) < 0)
+    if ((ret = xml_yang_validate_rpc(h, x, cbret)) < 0)
 	goto done;
     if (ret == 0)
 	goto reply;

apps/backend/backend_commit.c

@@ -87,7 +87,8 @@
  * @retval      1       Validation OK       
  */
 static int
-generic_validate(yang_stmt          *yspec,
+generic_validate(clicon_handle       h,
+		 yang_stmt          *yspec,
 		 transaction_data_t *td,
 		 cbuf               *cbret)
 {
@@ -99,7 +100,7 @@ generic_validate(yang_stmt          *yspec,
     int             ret;
 
     /* All entries */
-    if ((ret = xml_yang_validate_all_top(td->td_target, cbret)) < 0) 
+    if ((ret = xml_yang_validate_all_top(h, td->td_target, cbret)) < 0) 
 	goto done;
     if (ret == 0)
 	goto fail;
@@ -108,7 +109,7 @@ generic_validate(yang_stmt          *yspec,
 	x1 = td->td_scvec[i]; /* source changed */
 	x2 = td->td_tcvec[i]; /* target changed */
 	/* Should this be recursive? */
-	if ((ret = xml_yang_validate_add(x2, cbret)) < 0)
+	if ((ret = xml_yang_validate_add(h, x2, cbret)) < 0)
 	    goto done;
 	if (ret == 0)
 	    goto fail;
@@ -126,7 +127,7 @@ generic_validate(yang_stmt          *yspec,
     /* added entries */
     for (i=0; i<td->td_alen; i++){
 	x2 = td->td_avec[i];
-	if ((ret = xml_yang_validate_add(x2, cbret)) < 0)
+	if ((ret = xml_yang_validate_add(h, x2, cbret)) < 0)
 	    goto done;
 	if (ret == 0)
 	    goto fail;
@@ -224,7 +225,7 @@ startup_common(clicon_handle       h,
     /* 5. Make generic validation on all new or changed data.
        Note this is only call that uses 3-values */
     clicon_debug(1, "Validating startup %s", db);
-    if ((ret = generic_validate(yspec, td, cbret)) < 0)
+    if ((ret = generic_validate(h, yspec, td, cbret)) < 0)
 	goto done;
     if (ret == 0)
 	goto fail; /* STARTUP_INVALID */
@@ -408,7 +409,7 @@ from_validate_common(clicon_handle       h,
      * But xml_diff requires some basic validation, at least check that yang-specs
      * have been assigned
      */
-    if ((ret = xml_yang_validate_all_top(td->td_target, cbret)) < 0)
+    if ((ret = xml_yang_validate_all_top(h, td->td_target, cbret)) < 0)
 	goto done;
     if (ret == 0)
 	goto fail;
@@ -461,7 +462,7 @@ from_validate_common(clicon_handle       h,
 
     /* 5. Make generic validation on all new or changed data.
        Note this is only call that uses 3-values */
-    if ((ret = generic_validate(yspec, td, cbret)) < 0)
+    if ((ret = generic_validate(h, yspec, td, cbret)) < 0)
 	goto done;
     if (ret == 0)
 	goto fail;

apps/backend/backend_main.c

@@ -497,6 +497,12 @@ main(int    argc,
     if (help)
 	usage(h, argv[0]);
 
+#ifndef HAVE_LIBXML2
+    if (strcmp(clicon_yang_regexp(h), "libxml2")==0){
+	clicon_err(OE_FATAL, 0, "CLICON_YANG_REGEXP set to libxml2, but HAVE_LIBXM2 not set (Either change CLICON_YANG_REGEXP to posix, or install libxml2?))");
+	goto done;
+    }
+#endif
     /* Check pid-file, if zap kil the old daemon, else return here */
     if ((pidfile = clicon_backend_pidfile(h)) == NULL){
 	clicon_err(OE_FATAL, 0, "pidfile not set");

apps/cli/cli_generate.c

@@ -359,6 +359,9 @@ yang2cli_var_sub(clicon_handle h,
 	    goto done;
     }
     if (options & YANG_OPTIONS_PATTERN){
+	char *mode;
+	mode = clicon_yang_regexp(h);
+	if (strcmp(mode, "posix") == 0){
 	    char *posix = NULL;
 	    if (regexp_xsd2posix(pattern, &posix) < 0)
 		goto done;
@@ -366,6 +369,9 @@ yang2cli_var_sub(clicon_handle h,
 	    if (posix)
 		free(posix);
 	}
+	else
+	    cprintf(cb, " regexp:\"%s\"", pattern);
+    }
     cprintf(cb, ">");
     if (helptext)
 	cprintf(cb, "(\"%s\")", helptext);

apps/cli/cli_main.c

@@ -446,6 +446,16 @@ main(int argc, char **argv)
     if (help)
 	usage(h, argv[0]);
 
+    if (strcmp(clicon_yang_regexp(h), "libxml2")==0){
+#ifdef HAVE_LIBXML2
+	/* Enable XSD libxml2 */
+	cligen_regex_set(cli_cligen(h), 1);
+#else
+	clicon_err(OE_FATAL, 0, "CLICON_YANG_REGEXP set to libxml2, but HAVE_LIBXM2 not set (Either change CLICON_YANG_REGEXP to posix, or install libxml2?))");
+	goto done;
+#endif
+    }
+
     /* Setup signal handlers */
     cli_signal_init(h);
 

apps/netconf/netconf_main.c

@@ -125,7 +125,7 @@ netconf_input_packet(clicon_handle h,
         isrpc++;
 	if (xml_spec_populate_rpc(h, xrpc, yspec) < 0)
 	    goto done;
-	if ((ret = xml_yang_validate_rpc(xrpc, cbret)) < 0) 
+	if ((ret = xml_yang_validate_rpc(h, xrpc, cbret)) < 0) 
 	    goto done;
 	if (ret == 0){
 	    netconf_output_encap(1, cbret, "rpc-error");

apps/netconf/netconf_rpc.c

@@ -587,13 +587,13 @@ netconf_application_rpc(clicon_handle h,
 	    xml_spec_set(xn, yinput); /* needed for xml_spec_populate */
 	    if (xml_apply(xn, CX_ELMNT, xml_spec_populate, yspec) < 0)
 		goto done;
-	    if ((ret = xml_yang_validate_all_top(xn, cbret)) < 0)
+	    if ((ret = xml_yang_validate_all_top(h, xn, cbret)) < 0)
 		goto done;
 	    if (ret == 0){
 		netconf_output_encap(1, cbret, "rpc-error");
 		goto ok;
 	    }
-	    if ((ret = xml_yang_validate_add(xn, cbret)) < 0)
+	    if ((ret = xml_yang_validate_add(h, xn, cbret)) < 0)
 		goto done;
 	    if (ret == 0){
 		netconf_output_encap(1, cbret, "rpc-error");
@@ -622,13 +622,13 @@ netconf_application_rpc(clicon_handle h,
 	    if (xml_apply(xoutput, CX_ELMNT, xml_spec_populate, yspec) < 0)
 		goto done;
 
-	    if ((ret = xml_yang_validate_all_top(xoutput, cbret)) < 0)
+	    if ((ret = xml_yang_validate_all_top(h, xoutput, cbret)) < 0)
 		goto done;
 	    if (ret == 0){
 		clicon_log(LOG_WARNING, "Errors in output netconf %s", cbuf_get(cbret));
 		goto ok;
 	    }
-	    if ((ret = xml_yang_validate_add(xoutput, cbret)) < 0)
+	    if ((ret = xml_yang_validate_add(h, xoutput, cbret)) < 0)
 		goto done;
 	    if (ret == 0){
 		clicon_log(LOG_WARNING, "Errors in output netconf %s", cbuf_get(cbret));

apps/restconf/restconf_methods.c

@@ -1513,7 +1513,7 @@ api_operations_post_output(clicon_handle h,
 	if ((ret = xml_yang_validate_all(xoutput, cbret)) < 0)
 	    goto done;
 	if (ret == 1 &&
-	    (ret = xml_yang_validate_add(xoutput, cbret)) < 0)
+	    (ret = xml_yang_validate_add(h, xoutput, cbret)) < 0)
 	    goto done;
 	if (ret == 0){ /* validation failed */
 	    if (xml_parse_string(cbuf_get(cbret), yspec, &xerr) < 0)
@@ -1749,7 +1749,7 @@ api_operations_post(clicon_handle h,
     /* 6. Validate incoming RPC and fill in defaults */
     if (xml_spec_populate_rpc(h, xtop, yspec) < 0) /*  */
 	goto done;
-    if ((ret = xml_yang_validate_rpc(xtop, cbret)) < 0)
+    if ((ret = xml_yang_validate_rpc(h, xtop, cbret)) < 0)
 	goto done;
     if (ret == 0){
 	if (xml_parse_string(cbuf_get(cbret), NULL, &xret) < 0)

configure

@@ -2162,7 +2162,7 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
-# Default CFLAGS unless set by environment
+# Default CFLAGS and INSTALLFLAGS unless set by environment
 : ${CFLAGS="-O2 -Wall"}
 : ${INSTALLFLAGS="-s"}
 
@@ -4417,8 +4417,7 @@ _ACEOF
 fi
 
 
-# This is for Libxml2 code which we can use for XSD regexp
+# This is for libxml2 code which we can use for XSD regexp
-# AC_CHECK_HEADERS([libxml2/libxml/xmlexports.h])
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for xmlRegexpCompile in -lxml2" >&5
 $as_echo_n "checking for xmlRegexpCompile in -lxml2... " >&6; }
 if ${ac_cv_lib_xml2_xmlRegexpCompile+:} false; then :
@@ -4465,6 +4464,23 @@ _ACEOF
 fi
 
 
+# Libxml2 may hide its include files under /usr/include/libxml2/libxml
+# You may need to prepend CFLAGS="-I/usr/include/libxml2 to configure
+for ac_header in libxml/xmlregexp.h
+do :
+  ac_fn_c_check_header_compile "$LINENO" "libxml/xmlregexp.h" "ac_cv_header_libxml_xmlregexp_h" "#include \"libxml/xmlversion.h\"
+"
+if test "x$ac_cv_header_libxml_xmlregexp_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBXML_XMLREGEXP_H 1
+_ACEOF
+
+fi
+
+done
+
+
+#
 for ac_func in inet_aton sigaction sigvec strlcpy strsep strndup alphasort versionsort
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`

configure.ac

@@ -38,7 +38,7 @@
 
 AC_INIT(lib/clixon/clixon.h.in)
 
-# Default CFLAGS unless set by environment
+# Default CFLAGS and INSTALLFLAGS unless set by environment
 : ${CFLAGS="-O2 -Wall"}
 : ${INSTALLFLAGS="-s"}
 
@@ -220,10 +220,14 @@ AC_CHECK_LIB(socket, socket)
 AC_CHECK_LIB(nsl, xdr_char)
 AC_CHECK_LIB(dl, dlopen)
 
-# This is for Libxml2 code which we can use for XSD regexp
+# This is for libxml2 code which we can use for XSD regexp
-# AC_CHECK_HEADERS([libxml2/libxml/xmlexports.h])
 AC_CHECK_LIB(xml2, xmlRegexpCompile)
 
+# Libxml2 may hide its include files under /usr/include/libxml2/libxml
+# You may need to prepend CFLAGS="-I/usr/include/libxml2 to configure
+AC_CHECK_HEADERS([libxml/xmlregexp.h], [], [], [#include "libxml/xmlversion.h"])
+
+#
 AC_CHECK_FUNCS(inet_aton sigaction sigvec strlcpy strsep strndup alphasort versionsort)
 
 # CLIXON_DATADIR is where clixon installs the "system" yang files in yang/Makfile

include/clixon_config.h.in

@@ -60,6 +60,9 @@
 /* Define to 1 if you have the `xml2' library (-lxml2). */
 #undef HAVE_LIBXML2
 
+/* Define to 1 if you have the <libxml/xmlregexp.h> header file. */
+#undef HAVE_LIBXML_XMLREGEXP_H
+
 /* Define to 1 if you have the <linux/if_vlan.h> header file. */
 #undef HAVE_LINUX_IF_VLAN_H
 

lib/clixon/clixon.h.in

@@ -84,6 +84,7 @@
 #include <clixon/clixon_plugin.h>
 #include <clixon/clixon_options.h>
 #include <clixon/clixon_data.h>
+#include <clixon/clixon_regex.h>
 #include <clixon/clixon_xml_map.h>
 #include <clixon/clixon_datastore.h>
 #include <clixon/clixon_xpath_ctx.h>

lib/clixon/clixon_options.h

@@ -129,6 +129,9 @@ static inline char *clicon_yang_module_main(clicon_handle h){
 static inline char *clicon_yang_module_revision(clicon_handle h){
     return clicon_option_str(h, "CLICON_YANG_MODULE_REVISION");
 }
+static inline char *clicon_yang_regexp(clicon_handle h){
+    return clicon_option_str(h, "CLICON_YANG_REGEXP");
+}
 static inline char *clicon_backend_dir(clicon_handle h){
     return clicon_option_str(h, "CLICON_BACKEND_DIR");
 }

lib/clixon/clixon_regex.h

@@ -0,0 +1,46 @@
+/*
+ *
+  ***** BEGIN LICENSE BLOCK *****
+ 
+  Copyright (C) 2009-2019 Olof Hagsand and Benny Holmgren
+
+  This file is part of CLIXON.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+  Alternatively, the contents of this file may be used under the terms of
+  the GNU General Public License Version 3 or later (the "GPL"),
+  in which case the provisions of the GPL are applicable instead
+  of those above. If you wish to allow use of your version of this file only
+  under the terms of the GPL, and not to allow others to
+  use your version of this file under the terms of Apache License version 2, 
+  indicate your decision by deleting the provisions above and replace them with
+  the  notice and other provisions required by the GPL. If you do not delete
+  the provisions above, a recipient may use your version of this file under
+  the terms of any one of the Apache License version 2 or the GPL.
+
+  ***** END LICENSE BLOCK *****
+
+ */
+
+#ifndef _CLIXON_REGEX_H_
+#define _CLIXON_REGEX_H_
+
+/*
+ * Prototypes
+ */ 
+int regexp_xsd2posix(char *xsd, char **posix);
+int regex_compile(clicon_handle h, char *regexp, void **recomp);
+int regex_exec(clicon_handle h, void *recomp, char *string);
+
+#endif  /* _CLIXON_REGEX_H_ */

lib/clixon/clixon_string.h

@@ -89,7 +89,6 @@ int clicon_str2int(const map_str2int *mstab, char *str);
 int clicon_str2int_search(const map_str2int *mstab, char *str, int upper);
 int nodeid_split(char *nodeid,	char **prefix, char **id);
 char *clixon_trim(char *str);
-int regexp_xsd2posix(char *xsd, char **posix);
 #ifndef HAVE_STRNDUP
 char *clicon_strndup (const char *, size_t);
 #endif /* ! HAVE_STRNDUP */

lib/clixon/clixon_xml_map.h

@@ -48,11 +48,11 @@ int xml2txt(FILE *f, cxobj *x, int level);
 int xml2cli(FILE *f, cxobj *x, char *prepend, enum genmodel_type gt);
 int xml_yang_root(cxobj *x, cxobj **xr);
 int xmlns_assign(cxobj *x);
-int xml_yang_validate_rpc(cxobj *xrpc, cbuf *cbret);
+int xml_yang_validate_rpc(clicon_handle h, cxobj *xrpc, cbuf *cbret);
-int xml_yang_validate_list_key_only(cxobj *xt, cbuf *cbret);
+int xml_yang_validate_list_key_only(clicon_handle h, cxobj *xt, cbuf *cbret);
-int xml_yang_validate_add(cxobj *xt, cbuf *cbret);
+int xml_yang_validate_add(clicon_handle h, cxobj *xt, cbuf *cbret);
-int xml_yang_validate_all(cxobj *xt, cbuf *cbret);
+int xml_yang_validate_all(clicon_handle h, cxobj *xt, cbuf *cbret);
-int xml_yang_validate_all_top(cxobj *xt, cbuf *cbret);
+int xml_yang_validate_all_top(clicon_handle h, cxobj *xt, cbuf *cbret);
 int xml2cvec(cxobj *xt, yang_stmt *ys, cvec **cvv0);
 int cvec2xml_1(cvec *cvv, char *toptag, cxobj *xp, cxobj **xt0);
 

lib/clixon/clixon_yang_type.h

@@ -67,7 +67,7 @@ int        ys_resolve_type(yang_stmt *ys, void *arg);
 int        yang2cv_type(char *ytype, enum cv_type *cv_type);
 char      *cv2yang_type(enum cv_type cv_type);
 yang_stmt *yang_find_identity(yang_stmt *ys, char *identity);
-int        ys_cv_validate(cg_var *cv, yang_stmt *ys, char **reason);
+int        ys_cv_validate(clicon_handle h, cg_var *cv, yang_stmt *ys, char **reason);
 int        clicon_type2cv(char *type, char *rtype, yang_stmt *ys, enum cv_type *cvtype);
 int        yang_type_get(yang_stmt *ys, char **otype, yang_stmt **restype, 
 			 int *options, cvec **cvv, char **pattern,

lib/src/Makefile.in

@@ -67,7 +67,7 @@ CPPFLAGS  	= @CPPFLAGS@
 INCLUDES = -I. @INCLUDES@ -I$(top_srcdir)/lib/clixon -I$(top_srcdir)/include -I$(top_srcdir)
 
 SRC     = clixon_sig.c clixon_log.c clixon_err.c clixon_event.c \
-	  clixon_string.c clixon_handle.c  \
+	  clixon_string.c clixon_regex.c clixon_handle.c  \
 	  clixon_xml.c clixon_xml_sort.c clixon_xml_map.c clixon_file.c \
 	  clixon_json.c clixon_yang.c clixon_yang_type.c clixon_yang_module.c \
           clixon_yang_cardinality.c clixon_xml_changelog.c \

lib/src/clixon_options.c

@@ -198,7 +198,7 @@ parse_configfile(clicon_handle  h,
 	clicon_err(OE_XML, errno, "cbuf_new");
 	goto done;	
     }
-    if ((ret = xml_yang_validate_add(xc, cbret)) < 0)
+    if ((ret = xml_yang_validate_add(h, xc, cbret)) < 0)
 	goto done;
     if (ret == 0){
 	clicon_err(OE_CFG, 0, "Config file validation: %s", cbuf_get(cbret));

lib/src/clixon_regex.c

@@ -0,0 +1,272 @@
+/*
+ *
+  ***** BEGIN LICENSE BLOCK *****
+ 
+  Copyright (C) 2009-2019 Olof Hagsand and Benny Holmgren
+
+  This file is part of CLIXON.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+  Alternatively, the contents of this file may be used under the terms of
+  the GNU General Public License Version 3 or later (the "GPL"),
+  in which case the provisions of the GPL are applicable instead
+  of those above. If you wish to allow use of your version of this file only
+  under the terms of the GPL, and not to allow others to
+  use your version of this file under the terms of Apache License version 2, 
+  indicate your decision by deleting the provisions above and replace them with
+  the  notice and other provisions required by the GPL. If you do not delete
+  the provisions above, a recipient may use your version of this file under
+  the terms of any one of the Apache License version 2 or the GPL.
+
+  ***** END LICENSE BLOCK *****
+  *
+  * Clixon regular expression code for Yang type patterns following XML Schema
+  * regex. 
+  * Two modes: libxml2 and posix-translation
+ * @see http://www.w3.org/TR/2004/REC-xmlschema-2-20041028
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "clixon_config.h"
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <regex.h>
+#include <ctype.h>
+
+#ifdef HAVE_LIBXML_XMLREGEXP_H
+#include <libxml/xmlregexp.h>
+#endif
+
+#include <cligen/cligen.h>
+
+/* clicon */
+#include "clixon_queue.h"
+#include "clixon_hash.h"
+#include "clixon_handle.h"
+#include "clixon_err.h"
+#include "clixon_log.h"
+#include "clixon_yang.h"
+#include "clixon_options.h"
+#include "clixon_regex.h"
+
+/*-------------------------- POSIX translation -------------------------*/
+
+/*! Transform from XSD regex to posix ERE
+ * The usecase is that Yang (RFC7950) supports XSD regular expressions but
+ * CLIgen supports POSIX ERE
+ * POSIX ERE regexps according to man regex(3).
+ * @param[in]  xsd    Input regex string according XSD
+ * @param[out] posix  Output (malloced) string according to POSIX ERE
+ * @see https://www.w3.org/TR/2004/REC-xmlschema-2-20041028/#regexs
+ * @see https://www.regular-expressions.info/posixbrackets.html#class translation
+ * @see https://www.regular-expressions.info/xml.html
+ * Translation is not complete but covers some character sequences:
+ * \d decimal digit
+ * \w all characters except the set of "punctuation", "separator" and 
+ *    "other" characters: #x0000-#x10FFFF]-[\p{P}\p{Z}\p{C}]
+ * \i letters + underscore and colon
+ * \c XML Namechar, see: https://www.w3.org/TR/2008/REC-xml-20081126/#NT-NameChar
+ *
+ * Not implemented:
+ * \p{X} category escape.  the ones identified in openconfig and yang-models are: 
+ *   \p{L} Letters     [ultmo]?
+ *   \p{M} Marks       [nce]?
+ *   \p{N} Numbers     [dlo]?
+ *   \p{P} Punctuation [cdseifo]?
+ *   \p{Z} Separators  [slp]?
+ *   \p{S} Symbols     [mcko]?
+ *   \p{O} Other       [cfon]?
+ */
+int
+regexp_xsd2posix(char  *xsd,
+		 char **posix)
+{
+    int   retval = -1;
+    cbuf *cb = NULL;
+    char  x;
+    int   i;
+    int   j; /* lookahead */
+    int   esc;
+    int   minus = 0;
+
+    if ((cb = cbuf_new()) == NULL){
+	clicon_err(OE_UNIX, errno, "cbuf_new");
+	goto done;
+    }
+    esc=0;
+    for (i=0; i<strlen(xsd); i++){
+	x = xsd[i];
+	if (esc){
+	    esc = 0;
+	    switch (x){
+	    case '-': /* \- is translated to -], ie must be last in bracket */
+		minus++;
+		break;
+	    case 'c': /* xml namechar */
+		cprintf(cb, "[0-9a-zA-Z._:-]"); /* also interpunct */
+		break;
+	    case 'd':
+		cprintf(cb, "[0-9]");
+		break;
+	    case 'i': /* initial */
+		cprintf(cb, "[a-zA-Z_:]");
+		break;
+	    case 'p': /* category escape: \p{IsCategory} */
+		j = i+1;
+		if (j+2 < strlen(xsd) &&
+		    xsd[j] == '{' &&
+		    (xsd[j+2] == '}' || xsd[j+3] == '}')){
+		    switch (xsd[j+1]){
+		    case 'L': /* Letters */
+			cprintf(cb, "a-zA-Z"); /* assume in [] */
+			break;
+		    case 'M': /* Marks */
+			cprintf(cb, "\?!"); /* assume in [] */
+			break;
+		    case 'N': /* Numbers */
+			cprintf(cb, "0-9");
+			break;
+		    case 'P': /* Punctuation */
+			cprintf(cb, "a-zA-Z"); /* assume in [] */
+			break;
+		    case 'Z': /* Separators */
+			cprintf(cb, "\t "); /* assume in [] */
+			break;
+		    case 'S': /* Symbols */
+			 /* assume in [] */
+			break;
+		    case 'C': /* Others */
+			 /* assume in [] */
+			break;
+		    default:
+			break;
+		    }
+		    if (xsd[j+2] == '}')
+			i = j+2;
+		    else
+			i = j+3;
+		}
+		/* if syntax error, just leave it */
+		break;
+	    case 's':
+		cprintf(cb, "[ \t\r\n]");
+		break;
+	    case 'S':
+		cprintf(cb, "[^ \t\r\n]");
+		break;
+	    case 'w': /* word */
+		//cprintf(cb, "[0-9a-zA-Z_\\\\-]")
+		cprintf(cb, "[^[:punct:][:space:][:cntrl:]]"); 
+		break;
+	    case 'W': /* inverse of \w */
+		cprintf(cb, "[[:punct:][:space:][:cntrl:]]"); 
+		break;
+	    default:
+		cprintf(cb, "\\%c", x);
+		break;
+	    }
+	}
+	else if (x == '\\')
+	    esc++;
+	else if (x == '$')
+	    cprintf(cb, "\\%c", x);
+	else if (x == ']' && minus){
+	    cprintf(cb, "-]");
+	    minus = 0;
+	}
+	else
+	    cprintf(cb, "%c", x);
+    }
+    if ((*posix = strdup(cbuf_get(cb))) == NULL){
+	clicon_err(OE_UNIX, errno, "strdup");
+	goto done;
+    }
+    retval = 0;
+ done:
+    if (cb)
+	cbuf_free(cb);
+    return retval;
+}
+
+/*-------------------------- Generic API functions ------------------------*/
+
+/*! Compilation of regular expression / pattern
+ * @param[in]   h       Clicon handle
+ * @param[in]   regexp  Regular expression string in XSD regex format
+ * @param[out]  recomp  Compiled regular expression (malloc:d, should be freed)
+ * @retval      1       OK
+ * @retval      0       Invalid regular expression (syntax error?)
+ * @retval     -1       Error
+ * @note Clixon supports Yang's XSD regexp only. But CLIgen can support both
+ *       POSIX and XSD(using libxml2). But to use CLIgen's POSIX, Clixon must
+ *       translate from XSD to POSIX.
+ */
+int
+regex_compile(clicon_handle h,
+	      char         *regexp,
+	      void        **recomp)
+{
+    int   retval = -1;
+    char *mode;
+    char *posix = NULL;    /* Transform to posix regex */
+
+    mode = clicon_yang_regexp(h);
+    if (strcmp(mode, "posix") == 0){
+	if (regexp_xsd2posix(regexp, &posix) < 0)
+	    goto done;
+	retval = cligen_regex_posix_compile(posix, recomp);
+    }
+    else if (strcmp(mode, "libxml2") == 0)
+	retval = cligen_regex_libxml2_compile(regexp, recomp);
+    else{
+    	clicon_err(OE_CFG, 0, "clicon_yang_regexp invalid value: %s", mode);
+	goto done;
+    }
+    /* retval from fns above */
+ done:
+    if (posix)
+	free(posix);
+    return retval;
+}
+
+/*! Execution of (pre-compiled) regular expression / pattern
+ * @param[in]  h   Clicon handle
+ */
+int
+regex_exec(clicon_handle h,
+	   void         *recomp,
+	   char         *string)
+{
+    int   retval = -1;
+    char *mode;
+
+    mode = clicon_yang_regexp(h);
+    if (strcmp(mode, "posix") == 0)
+	retval = cligen_regex_posix_exec(recomp, string);
+    else if (strcmp(mode, "libxml2") == 0)
+	retval = cligen_regex_libxml2_exec(recomp, string);
+    else{
+    	clicon_err(OE_CFG, 0, "clicon_yang_regexp invalid value: %s", mode);
+	goto done;
+    }
+    /* retval from fns above */
+ done:
+    return retval;
+}
+

lib/src/clixon_string.c

@@ -30,10 +30,7 @@
   the terms of any one of the Apache License version 2 or the GPL.
 
   ***** END LICENSE BLOCK *****
-
  */
-/* Error handling: dont use clicon_err, treat as unix system calls. That is,
-   ensure errno is set and return -1/NULL */
 
 #ifdef HAVE_CONFIG_H
 #include "clixon_config.h"
@@ -44,7 +41,6 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <errno.h>
-#include <regex.h>
 #include <ctype.h>
 
 #include <cligen/cligen.h>
@@ -694,120 +690,6 @@ clixon_trim(char *str)
     return s;
 }
 
-/*! Transform from XSD regex to posix ERE
- * The usecase is that Yang (RFC7950) supports XSD regular expressions but
- * CLIgen supports POSIX ERE
- * POSIX ERE regexps according to man regex(3).
- * @param[in]  xsd    Input regex string according XSD
- * @param[out] posix  Output (malloced) string according to POSIX ERE
- * @see https://www.w3.org/TR/2004/REC-xmlschema-2-20041028/#regexs
- * @see https://www.regular-expressions.info/posixbrackets.html#class translation
- * @see https://www.regular-expressions.info/xml.html
- * Translation is not complete but covers some character sequences:
- * \d decimal digit
- * \w all characters except the set of "punctuation", "separator" and 
- *    "other" characters: #x0000-#x10FFFF]-[\p{P}\p{Z}\p{C}]
- * \i letters + underscore and colon
- * \c XML Namechar, see: https://www.w3.org/TR/2008/REC-xml-20081126/#NT-NameChar
- *
- * Not implemented:
- * \p{X} category escape.  the ones identified in openconfig and yang-models are: 
- *   \p{L} Letters [ultmo]?
- *   \p{N} Numbers [dlo]?
- */
-int
-regexp_xsd2posix(char  *xsd,
-		 char **posix)
-{
-    int   retval = -1;
-    cbuf *cb = NULL;
-    char  x;
-    int   i;
-    int   j; /* lookahead */
-    int   esc;
-    int   minus = 0;
-
-    if ((cb = cbuf_new()) == NULL){
-	clicon_err(OE_UNIX, errno, "cbuf_new");
-	goto done;
-    }
-    esc=0;
-    for (i=0; i<strlen(xsd); i++){
-	x = xsd[i];
-	if (esc){
-	    esc = 0;
-	    switch (x){
-	    case '-': /* \- is translated to -], ie must be last in bracket */
-		minus++;
-		break;
-	    case 'c': /* xml namechar */
-		cprintf(cb, "[0-9a-zA-Z._:-]"); /* also interpunct */
-		break;
-	    case 'd':
-		cprintf(cb, "[0-9]");
-		break;
-	    case 'i': /* initial */
-		cprintf(cb, "[a-zA-Z_:]");
-		break;
-	    case 'p': /* category escape: \p{IsCategory} */
-		j = i+1;
-		if (j+2 < strlen(xsd) &&
-		    xsd[j] == '{' &&
-		    xsd[j+2] == '}'){
-		    switch (xsd[j+1]){
-		    case 'L': /* Letters */
-			cprintf(cb, "a-zA-Z"); /* assume in [] */
-			break;
-		    case 'N': /* Numbers */
-			cprintf(cb, "0-9");
-			break;
-		    default:
-			break;
-		    }
-		    i = j+2;
-		}
-		/* if syntax error, just leave it */
-		break;
-	    case 's':
-		cprintf(cb, "[ \t\r\n]");
-		break;
-	    case 'S':
-		cprintf(cb, "[^ \t\r\n]");
-		break;
-	    case 'w': /* word */
-		//cprintf(cb, "[0-9a-zA-Z_\\\\-]")
-		cprintf(cb, "[^[:punct:][:space:][:cntrl:]]"); 
-		break;
-	    case 'W': /* inverse of \w */
-		cprintf(cb, "[[:punct:][:space:][:cntrl:]]"); 
-		break;
-	    default:
-		cprintf(cb, "\\%c", x);
-		break;
-	    }
-	}
-	else if (x == '\\')
-	    esc++;
-	else if (x == '$')
-	    cprintf(cb, "\\%c", x);
-	else if (x == ']' && minus){
-	    cprintf(cb, "-]");
-	    minus = 0;
-	}
-	else
-	    cprintf(cb, "%c", x);
-    }
-    if ((*posix = strdup(cbuf_get(cb))) == NULL){
-	clicon_err(OE_UNIX, errno, "strdup");
-	goto done;
-    }
-    retval = 0;
- done:
-    if (cb)
-	cbuf_free(cb);
-    return retval;
-}
-
 /*! strndup() for systems without it, such as xBSD
  */
 #ifndef HAVE_STRNDUP

lib/src/clixon_xml_changelog.c

@@ -441,9 +441,9 @@ clixon_xml_changelog_init(clicon_handle h)
 	    clicon_err(OE_UNIX, errno, "cbuf_new");
 	    goto done;
 	}
-	if ((ret = xml_yang_validate_all(xt, cbret)) < 0)
+	if ((ret = xml_yang_validate_all(h, xt, cbret)) < 0)
 	    goto done;
-	if (ret==1 && (ret = xml_yang_validate_add(xt, cbret)) < 0)
+	if (ret==1 && (ret = xml_yang_validate_add(h, xt, cbret)) < 0)
 	    goto done;
 	if (ret == 0){ /* validation failed */
 	    clicon_err(OE_YANG, 0, "validation failed: %s", cbuf_get(cbret));

lib/src/clixon_xml_map.c

@@ -453,7 +453,8 @@ xml_yang_root(cxobj  *x,
  * @note Should need a variant accepting cxobj **xret
  */
 int
-xml_yang_validate_rpc(cxobj *xrpc,
+xml_yang_validate_rpc(clicon_handle h,
+		      cxobj *xrpc,
 		      cbuf  *cbret)
 {
     int        retval = -1;
@@ -472,9 +473,9 @@ xml_yang_validate_rpc(cxobj *xrpc,
 		goto done;
 	    goto fail;
 	}
-	if ((retval = xml_yang_validate_all(xn, cbret)) < 1) 
+	if ((retval = xml_yang_validate_all(h, xn, cbret)) < 1) 
 	    goto done; /* error or validation fail */
-	if ((retval = xml_yang_validate_add(xn, cbret)) < 1)
+	if ((retval = xml_yang_validate_add(h, xn, cbret)) < 1)
 	    goto done; /* error or validation fail */
 	if (xml_apply0(xn, CX_ELMNT, xml_default, NULL) < 0)
 	    goto done;
@@ -1020,7 +1021,7 @@ check_list_unique_minmax(cxobj *xt,
  * @code
  *   cxobj *x;
  *   cbuf *cbret = cbuf_new();
- *   if ((ret = xml_yang_validate_add(x, cbret)) < 0)
+ *   if ((ret = xml_yang_validate_add(h, x, cbret)) < 0)
  *      err;
  *   if (ret == 0)
  *      fail;
@@ -1030,7 +1031,8 @@ check_list_unique_minmax(cxobj *xt,
  * @note Should need a variant accepting cxobj **xret
  */
 int
-xml_yang_validate_add(cxobj   *xt, 
+xml_yang_validate_add(clicon_handle h,
+		      cxobj   *xt, 
 		      cbuf    *cbret)
 {
     int        retval = -1;
@@ -1084,7 +1086,7 @@ xml_yang_validate_add(cxobj   *xt,
 		}
 	    }
 
-	    if ((ys_cv_validate(cv, yt, &reason)) != 1){
+	    if ((ys_cv_validate(h, cv, yt, &reason)) != 1){
 		if (netconf_bad_element(cbret, "application",  yt->ys_argument, reason) < 0)
 		    goto done;
 		goto fail;
@@ -1096,7 +1098,7 @@ xml_yang_validate_add(cxobj   *xt,
     }
     x = NULL;
     while ((x = xml_child_each(xt, x, CX_ELMNT)) != NULL) {
-	if ((ret = xml_yang_validate_add(x, cbret)) < 0)
+	if ((ret = xml_yang_validate_add(h, x, cbret)) < 0)
 	    goto done;
 	if (ret == 0)
 	    goto fail;
@@ -1116,7 +1118,8 @@ xml_yang_validate_add(cxobj   *xt,
 /*! Some checks done only at edit_config, eg keys in lists
  */
 int
-xml_yang_validate_list_key_only(cxobj   *xt, 
+xml_yang_validate_list_key_only(clicon_handle h,
+				cxobj   *xt, 
 				cbuf    *cbret)
 {
     int        retval = -1;
@@ -1134,7 +1137,7 @@ xml_yang_validate_list_key_only(cxobj   *xt,
     }
     x = NULL;
     while ((x = xml_child_each(xt, x, CX_ELMNT)) != NULL) {
-	if ((ret = xml_yang_validate_list_key_only(x, cbret)) < 0)
+	if ((ret = xml_yang_validate_list_key_only(h, x, cbret)) < 0)
 	    goto done;
 	if (ret == 0)
 	    goto fail;
@@ -1168,7 +1171,8 @@ xml_yang_validate_list_key_only(cxobj   *xt,
  * @note Should need a variant accepting cxobj **xret
  */
 int
-xml_yang_validate_all(cxobj   *xt, 
+xml_yang_validate_all(clicon_handle h,
+		      cxobj   *xt, 
 		      cbuf    *cbret)
 {
     int        retval = -1;
@@ -1247,7 +1251,7 @@ xml_yang_validate_all(cxobj   *xt,
     }
     x = NULL;
     while ((x = xml_child_each(xt, x, CX_ELMNT)) != NULL) {
-	if ((ret = xml_yang_validate_all(x, cbret)) < 0)
+	if ((ret = xml_yang_validate_all(h, x, cbret)) < 0)
 	    goto done;
 	if (ret == 0)
 	    goto fail;
@@ -1275,7 +1279,8 @@ xml_yang_validate_all(cxobj   *xt,
  * @retval    -1     Error
  */
 int
-xml_yang_validate_all_top(cxobj   *xt, 
+xml_yang_validate_all_top(clicon_handle h,
+			  cxobj   *xt, 
 			  cbuf    *cbret)
 {
     int    ret;
@@ -1283,7 +1288,7 @@ xml_yang_validate_all_top(cxobj   *xt,
 
     x = NULL;
     while ((x = xml_child_each(xt, x, CX_ELMNT)) != NULL) {
-	if ((ret = xml_yang_validate_all(x, cbret)) < 1)
+	if ((ret = xml_yang_validate_all(h, x, cbret)) < 1)
 	    return ret;
     }
     if ((ret = check_list_unique_minmax(xt, cbret)) < 1)

lib/src/clixon_yang_type.c

@@ -62,6 +62,7 @@
 #include "clixon_queue.h"
 #include "clixon_hash.h"
 #include "clixon_handle.h"
+#include "clixon_regex.h"
 #include "clixon_yang.h"
 #include "clixon_hash.h"
 #include "clixon_xml.h"
@@ -128,74 +129,6 @@ static const map_str2int ytmap2[] = {
     {NULL,         -1}
 };
 
-/*! Regular expression compiling
- * @retval -1 Error
- * @retval  0 regex problem (no match?)
- * @retval  1 OK Match
- * @see match_regexp the CLIgen original composite function
- */
-static int
-regex_compile(char    *pattern0,
-	      regex_t *re)
-{
-    int  retval = -1;
-    char pattern[1024];
-    //    char errbuf[1024];
-    int  len0;
-    int  status;
-
-    len0 = strlen(pattern0);
-    if (len0 > sizeof(pattern)-5){
-	clicon_err(OE_XML, EINVAL, "pattern too long");
-	goto done;
-    }
-    strncpy(pattern, "^(", 2);
-    strncpy(pattern+2, pattern0, sizeof(pattern)-2);
-    strncat(pattern, ")$",  sizeof(pattern)-len0-1);
-    if ((status = regcomp(re, pattern, REG_NOSUB|REG_EXTENDED)) != 0) {
-#if 0 /* ignore error msg for now */
-	regerror(status, re, errbuf, sizeof(errbuf));
-#endif
-	goto fail;
-    }
-    retval = 1;
- done:
-    return retval;
- fail:
-    retval = 0;
-    goto done;
-}
-
-/*! Regular expression execution
- * @retval -1 Error
- * @retval  0 regex problem (no match?)
- * @retval  1 OK Match
- * @see match_regexp the CLIgen original composite function
- */
-static int
-regex_exec(regex_t *re,
-	   char    *string)
-{
-    int retval = -1;
-    int status;
-    //    char errbuf[1024];
-    
-    status = regexec(re, string, (size_t) 0, NULL, 0);
-    if (status != 0) {
-#if 0 /* ignore error msg for now */
-	regerror(status, re, errbuf, sizeof(errbuf));
-#endif
-	goto fail;
-    }
-    retval = 1;
- done:
-    return retval;
- fail:
-    retval = 0;
-    goto done;
-}
-
-
 /* return 1 if built-in, 0 if not */
 static int
 yang_builtin(char *type)
@@ -447,7 +380,8 @@ clicon_type2cv(char         *origtype,
  * @retval 1   Validation OK
  */
 static int
-cv_validate1(cg_var      *cv,
+cv_validate1(clicon_handle h,
+	     cg_var      *cv,
 	     enum cv_type cvtype, 
 	     int          options, 
 	     cvec        *cvv,
@@ -459,7 +393,7 @@ cv_validate1(cg_var      *cv,
     int             retval = 1; /* OK */
     cg_var         *cv1;
     cg_var         *cv2;
-    int             retval2;
+    int             ret;
     yang_stmt      *yi = NULL;
     char           *str = NULL;
     int             found;
@@ -620,44 +554,23 @@ cv_validate1(cg_var      *cv,
 		}
 	    }
 	}
-	if ((options & YANG_OPTIONS_PATTERN) != 0){
+	if ((options & YANG_OPTIONS_PATTERN) != 0) {
-	    char *posix = NULL;
+		void *re = NULL;
-	    regex_t *re = NULL;
-
 		if ((re = yang_regex_cache_get(yrestype)) == NULL){
-		/* Transform to posix regex */
+		    if ((ret = regex_compile(h, pattern, &re)) < 0)
-		if (regexp_xsd2posix(pattern, &posix) < 0)
 			goto done;
-		/* Create regex cache */
+		    if (ret == 0){
-		if ((re = malloc(sizeof(*re))) == NULL){
-		    clicon_err(OE_UNIX, errno, "malloc");		    
-		    goto done;
-		}
-		memset(re, 0, sizeof(*re));
-		/* Compute regex pattern for use in patterns */
-		if ((retval2 = regex_compile(posix, re)) < 0)
-		    goto done;
-		if (retval2 == 0){
 			if (reason)
-			*reason = cligen_reason("regexp match fail: \"%s\" does not match %s",
+			    *reason = cligen_reason("regexp compile fail: \"%s\"",
-						str, pattern);
+						    pattern);
 			goto fail;
 			break;
 		    }
 		    yang_regex_cache_set(yrestype, re);
-		if (posix)
-		    free(posix);
 		}
-	    if ((retval2 = regex_exec(re, str?str:"")) < 0)
+		if ((ret = regex_exec(h, re, str?str:"")) < 0)
 		    goto done;
-	    if (retval2 == 0){
+	    if (ret == 0){
-		if (reason)
-		    *reason = cligen_reason("regexp match fail: \"%s\" does not match %s",
-					    str, pattern);
-		goto fail;
-		break;
-	    }
-	    if (retval2 == 0){
 		if (reason)
 		    *reason = cligen_reason("regexp match fail: \"%s\" does not match %s",
 					    str, pattern);
@@ -688,8 +601,8 @@ cv_validate1(cg_var      *cv,
 }
 
 /* Forward */
-static int ys_cv_validate_union(yang_stmt *ys, char **reason, yang_stmt *yrestype,
+static int ys_cv_validate_union(clicon_handle h,yang_stmt *ys, char **reason,
-				char *type, char *val);
+				yang_stmt *yrestype, char *type, char *val);
 
 /*!
  * @retval -1  Error (fatal), with errno set to indicate error
@@ -697,7 +610,8 @@ static int ys_cv_validate_union(yang_stmt *ys, char **reason, yang_stmt *yrestyp
  * @retval 1   Validation OK
  */
 static int
-ys_cv_validate_union_one(yang_stmt *ys,
+ys_cv_validate_union_one(clicon_handle h,
+			 yang_stmt *ys,
 			 char     **reason,
 			 yang_stmt *yt,
 			 char      *type,  /* orig type */
@@ -718,7 +632,7 @@ ys_cv_validate_union_one(yang_stmt *ys,
 	goto done;
     restype = yrt?yrt->ys_argument:NULL;
     if (restype && strcmp(restype, "union") == 0){      /* recursive union */
-	if ((retval = ys_cv_validate_union(ys, reason, yrt, type, val)) < 0)
+	if ((retval = ys_cv_validate_union(h, ys, reason, yrt, type, val)) < 0)
 	    goto done;
     }
     else {
@@ -735,7 +649,7 @@ ys_cv_validate_union_one(yang_stmt *ys,
 	}
 	if (retval == 0)
 	    goto done;
-	if ((retval = cv_validate1(cvt, cvtype, options, cvv, 
+	if ((retval = cv_validate1(h, cvt, cvtype, options, cvv, 
 				   pattern, yrt, restype, reason)) < 0)
 	    goto done;
     }
@@ -751,7 +665,8 @@ ys_cv_validate_union_one(yang_stmt *ys,
  * @retval 1   Validation OK
  */
 static int
-ys_cv_validate_union(yang_stmt *ys,
+ys_cv_validate_union(clicon_handle h,
+		     yang_stmt *ys,
 		     char     **reason,
 		     yang_stmt *yrestype,
 		     char      *type,  /* orig type */
@@ -764,7 +679,7 @@ ys_cv_validate_union(yang_stmt *ys,
     while ((yt = yn_each(yrestype, yt)) != NULL){
 	if (yt->ys_keyword != Y_TYPE)
 	    continue;
-	if ((retval = ys_cv_validate_union_one(ys, reason, yt, type, val)) < 0)
+	if ((retval = ys_cv_validate_union_one(h, ys, reason, yt, type, val)) < 0)
 	    goto done;
 	/* If validation failed, save reason, reset error and continue,
 	 * save latest reason if noithing validates.
@@ -800,7 +715,8 @@ ys_cv_validate_union(yang_stmt *ys,
  * See also cv_validate - the code is similar.
  */
 int
-ys_cv_validate(cg_var    *cv, 
+ys_cv_validate(clicon_handle h,
+	       cg_var    *cv, 
 	       yang_stmt *ys, 
 	       char     **reason)
 {
@@ -846,12 +762,12 @@ ys_cv_validate(cg_var    *cv,
     if (restype && strcmp(restype, "union") == 0){ 
 	assert(cvtype == CGV_REST);
 	val = cv_string_get(cv);
-	if ((retval2 = ys_cv_validate_union(ys, reason, yrestype, type, val)) < 0)
+	if ((retval2 = ys_cv_validate_union(h, ys, reason, yrestype, type, val)) < 0)
 	    goto done;
 	retval = retval2; /* invalid (0) with latest reason or valid 1 */
     }
     else
-	if ((retval = cv_validate1(cv, cvtype, options, cvv, pattern,
+	if ((retval = cv_validate1(h, cv, cvtype, options, cvv, pattern,
 				   yrestype, restype, reason)) < 0)
 	    goto done;
   done:

test/test_pattern.sh

@@ -22,12 +22,16 @@ APPNAME=example
 cfg=$dir/pattern.xml
 fyang=$dir/pattern.yang
 
+# Regexp mode: posix or libxml2
+: ${regex:=posix}
+
 cat <<EOF > $cfg
 <clixon-config xmlns="http://clicon.org/config">
   <CLICON_CONFIGFILE>$cfg</CLICON_CONFIGFILE>
   <CLICON_YANG_DIR>/usr/local/share/clixon</CLICON_YANG_DIR>
   <CLICON_YANG_DIR>$dir</CLICON_YANG_DIR>
   <CLICON_YANG_MAIN_FILE>$fyang</CLICON_YANG_MAIN_FILE>
+  <CLICON_YANG_REGEXP>$regex</CLICON_YANG_REGEXP>
   <CLICON_CLISPEC_DIR>/usr/local/lib/$APPNAME/clispec</CLICON_CLISPEC_DIR>
   <CLICON_CLI_DIR>/usr/local/lib/$APPNAME/cli</CLICON_CLI_DIR>
   <CLICON_CLI_MODE>$APPNAME</CLICON_CLI_MODE>
@@ -457,7 +461,9 @@ new "Test for pattern leaf $pnr ipv6-prefix"
 testrun "$pnr" 1 '::9a95::A54:63:e001:6E1:15/17'
 testrun "$pnr" 1 ':::7:fc:c::eDe:/3'
 testrun "$pnr" 1 '7dE::D1e:8:8eBC::/98'
-testrun "$pnr" 1 ':29:F36:6:46.53.251.2/100' # This does not work w libxml2
+if [ $regex != libxml2 ]; then
+    testrun "$pnr" 1 ':29:F36:6:46.53.251.2/100' # This does not work w libxml2
+fi
 testrun "$pnr" 1 '::CE2e:A:AB:234.220.225.250/1'
 
 let pnr=15

yang/clixon/clixon-config@2019-03-05.yang

@@ -113,7 +113,6 @@ module clixon-config {
 	    }
 	}
     }
-
     typedef cli_genmodel_type{
 	description
 	    "How to generate CLI from YANG model, 
@@ -148,6 +147,30 @@ module clixon-config {
 	    }
 	}
     }
+    typedef regexp_mode{
+	description
+	    "The regular expression engine Clixon uses in its validation of
+             Yang patterns, and in the CLI.
+             Yang RFC 7950 stipulates XSD XML Schema regexps
+             according to W3 CXML Schema Part 2: Datatypes Second Edition,
+             see http://www.w3.org/TR/2004/REC-xmlschema-2-20041028#regexs";
+	type enumeration{
+	    enum posix {
+		description
+		  "Translate XSD XML Schema regexp:s to Posix regexp. This is 
+                   not a complete translation, but can be considered good-enough
+                   for Yang use-cases as defined by openconfig and yang-models
+                   for example.";
+	    }
+	    enum libxml2 {
+		description
+		  "Use libxml2 XSD XML Schema regexp engine. This is a complete
+                   XSD regexp engine..
+                   Requires libxml2 to be available at configure time 
+                   (HAVE_LIBXML2 should be set)";
+	    }
+	}
+    }
     container clixon-config {
        leaf-list CLICON_FEATURE {
            description
@@ -203,6 +226,15 @@ module clixon-config {
                  <module>[@<revision>].
                  Used together with CLICON_YANG_MODULE_MAIN";
 	}
+	leaf CLICON_YANG_REGEXP {
+	    type regexp_mode;
+	    default posix;
+	    description
+		"The regular expression engine Clixon uses in its validation of
+                 Yang patterns, and in the CLI.
+                 There is a 'good-enough' posix translation mode and a complete
+                 libxml2 mode";
+	}
 	leaf CLICON_BACKEND_DIR {
 	    type string;
 	    description