SNMP MIB->YANG translation file handling.

Added configure option  --with-mib-generated-yang-dir=DIR with
default value /usr/share/mibyang where generated YANGs from MIBs
should be placed so that SNMP tests know where to find the YANGs.

CHANGELOG.md

@@ -43,6 +43,9 @@
   * YANG `clixon-config@2022-03-21.yang` changes:
     * Added option:
       * `CLICON_SNMP_AGENT_SOCK`
+  * New configure options:
+    * `--enable-netsnmp`
+    * `--with-mib-generated-yang-dir=DIR`
   * Thanks Siklu for sponshoring 
 
 ## 5.8.0

configure

@@ -632,6 +632,7 @@ ac_ct_CXX
 CXXFLAGS
 CXX
 CPP
+MIB_GENERATED_YANG_DIR
 YANG_STANDARD_DIR
 YANG_INSTALLDIR
 CLIXON_YANG_PATCH
@@ -724,6 +725,7 @@ with_restconf
 enable_http1
 enable_nghttp2
 enable_netsnmp
+with_mib_generated_yang_dir
 with_configfile
 with_libxml2
 with_sigaction
@@ -1387,6 +1389,9 @@ Optional Packages:
   --with-restconf=fcgi    FCGI interface for stand-alone web rev-proxy eg
                           nginx
   --without-restconf      Disable restconf altogether
+  --with-mib-generated-yang-dir=DIR
+                          Directory of generated YANG specs (default:
+                          $prefix/share/mibyang)
   --with-configfile=FILE  Set default path to config file
   --with-libxml2          Use gnome/libxml2 regex engine
   --without-sigaction     Don't use sigaction
@@ -3400,6 +3405,8 @@ HAVE_HTTP1=false
 
 # Examples require standard IETF YANGs. You need to provide these for example and tests
 
+# SNMP tests require generated YANGs from MIBs
+
 
 #
 ac_ext=c
@@ -5429,6 +5436,23 @@ fi
 
 done
 
+
+
+   # MIB_GENERATED_YANG_DIR is where clixon assumes generated YANGs from MIBs are stored
+   # This is NOT installed by Clixon and is not needed for core system
+   # However, it is required by SNMP tests.
+   # To generate: for i in /usr/share/snmp/mibs/*; do smidump -f yang $i > `basename -s .txt $i`.yang; done
+
+# Check whether --with-mib-generated-yang-dir was given.
+if test "${with_mib_generated_yang_dir+set}" = set; then :
+  withval=$with_mib_generated_yang_dir; MIB_GENERATED_YANG_DIR="$withval"
+else
+  MIB_GENERATED_YANG_DIR="${prefix}/share/mibyang"
+
+fi
+
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: Generated YANGs from MIB files are expected to be in ${MIB_GENERATED_YANG_DIR}" >&5
+$as_echo "Generated YANGs from MIB files are expected to be in ${MIB_GENERATED_YANG_DIR}" >&6; }
 fi
 
 # Set default config file location

configure.ac

@@ -124,6 +124,8 @@ AC_SUBST(CLIXON_YANG_PATCH)
 AC_SUBST(YANG_INSTALLDIR) 
 # Examples require standard IETF YANGs. You need to provide these for example and tests
 AC_SUBST(YANG_STANDARD_DIR)
+# SNMP tests require generated YANGs from MIBs
+AC_SUBST(MIB_GENERATED_YANG_DIR)
 
 #
 AC_PROG_CC()
@@ -293,6 +295,18 @@ if test "$enable_netsnmp" = "yes"; then
    AC_CHECK_LIB(netsnmp, init_snmp)
    AC_CHECK_LIB(netsnmpagent, init_agent)	
    AC_CHECK_HEADERS(net-snmp/net-snmp-config.h,[], AC_MSG_ERROR([snmp is missing]))
+
+
+   # MIB_GENERATED_YANG_DIR is where clixon assumes generated YANGs from MIBs are stored
+   # This is NOT installed by Clixon and is not needed for core system
+   # However, it is required by SNMP tests.
+   # To generate: for i in /usr/share/snmp/mibs/*; do smidump -f yang $i > `basename -s .txt $i`.yang; done
+   AC_ARG_WITH(mib-generated-yang-dir,
+      [AS_HELP_STRING([--with-mib-generated-yang-dir=DIR],[Directory of generated YANG specs (default: $prefix/share/mibyang)])],
+      [MIB_GENERATED_YANG_DIR="$withval"],
+      [MIB_GENERATED_YANG_DIR="${prefix}/share/mibyang"]		
+    )
+    AC_MSG_RESULT(Generated YANGs from MIB files are expected to be in ${MIB_GENERATED_YANG_DIR})
 fi 
 
 # Set default config file location

lib/src/clixon_yang_parse_lib.c

@@ -790,7 +790,10 @@ yang_parse_str(char         *str,
 	if (yang_scan_exit(&yy) < 0)
 	    goto done;		
     }
-    ymod = yy.yy_module;
+    if ((ymod = yy.yy_module) == NULL){
+	clicon_err(OE_YANG, 0, "No module in YANG %s", name);
+	goto done;
+    }
     /* Add filename for debugging and errors, see also ys_linenum on (each symbol?) */
     if (yang_filename_set(ymod, name) < 0)
 	goto done;

test/config.sh.in

@@ -95,3 +95,4 @@ YANG_STANDARD_DIR=@YANG_STANDARD_DIR@
 
 YANG_INSTALLDIR=@YANG_INSTALLDIR@
 
+MIB_GENERATED_YANG_DIR=@MIB_GENERATED_YANG_DIR@

test/test_snmp.sh

@@ -24,6 +24,8 @@ cat <<EOF > $cfg
 <clixon-config xmlns="http://clicon.org/config">
   <CLICON_CONFIGFILE>$cfg</CLICON_CONFIGFILE>
   <CLICON_YANG_DIR>${YANG_INSTALLDIR}</CLICON_YANG_DIR>
+  <CLICON_YANG_DIR>${YANG_STANDARD_DIR}</CLICON_YANG_DIR>
+  <CLICON_YANG_DIR>${MIB_GENERATED_YANG_DIR}</CLICON_YANG_DIR>
   <CLICON_YANG_MAIN_FILE>$fyang</CLICON_YANG_MAIN_FILE>
   <CLICON_SOCK>$dir/$APPNAME.sock</CLICON_SOCK>
   <CLICON_BACKEND_PIDFILE>/var/tmp/$APPNAME.pidfile</CLICON_BACKEND_PIDFILE>
@@ -37,6 +39,9 @@ module clixon-example{
   yang-version 1.1;
   namespace "urn:example:clixon";
   prefix ex;
+  import NET-SNMP-EXAMPLES-MIB {
+      prefix "net-snmp-examples";
+  }
 }
 EOF
 
@@ -59,6 +64,7 @@ function testinit(){
 	err "Failed to start snmpd"
     fi
 
+    new "test params: -f $cfg"
     # Kill old backend and start a new one
     new "kill old backend"
     sudo clixon_backend -zf $cfg

test/test_snmp_table.sh

@@ -34,6 +34,8 @@ cat <<EOF > $cfg
 <clixon-config xmlns="http://clicon.org/config">
   <CLICON_CONFIGFILE>$cfg</CLICON_CONFIGFILE>
   <CLICON_YANG_DIR>${YANG_INSTALLDIR}</CLICON_YANG_DIR>
+  <CLICON_YANG_DIR>${YANG_STANDARD_DIR}</CLICON_YANG_DIR>
+  <CLICON_YANG_DIR>${MIB_GENERATED_YANG_DIR}</CLICON_YANG_DIR>
   <CLICON_YANG_MAIN_FILE>$fyang</CLICON_YANG_MAIN_FILE>
   <CLICON_SOCK>$dir/$APPNAME.sock</CLICON_SOCK>
   <CLICON_BACKEND_PIDFILE>/var/tmp/$APPNAME.pidfile</CLICON_BACKEND_PIDFILE>
@@ -47,6 +49,9 @@ module clixon-example{
   yang-version 1.1;
   namespace "urn:example:clixon";
   prefix ex;
+  import NET-SNMP-EXAMPLES-MIB {
+      prefix "net-snmp-examples";
+  }
 }
 EOF
 
@@ -69,6 +74,7 @@ function testinit(){
         err "Failed to start snmpd"
     fi
 
+    new "test params: -f $cfg"
     # Kill old backend and start a new one
     new "kill old backend"
     sudo clixon_backend -zf $cfg