beesh: add callback function bee_version

at the same time add utility function bee_die and relax the checks
so that we can update the full version string from inside the
bee file

src/beesh.sh.in

@@ -208,6 +208,20 @@ function build_in_sourcedir() {
    BUILD_IN_SOURCEDIR=1
 }
 
+function bee_die() {
+    print_error $*
+    exit 1
+}
+
+function bee_version() {
+    test -n "$1" || bee_die "bee_version: missing argument"
+    test "$PKGFULLVERSION"="0" -a -z "$PKGREVISION" || bee_die "bee_version: version is already fixed"
+    local oPKGFULLNAME="$PKGFULLNAME"
+    eval $("${BEE_BINDIR}/beeversion" "$1") || bee_die "bee_version: invalid version string"
+    validate_pkg_complete || bee_die "bee_version: please use the proper package versioning (e.g. package-1.0-0)"
+    test "$PKGFULLNAME" = "$oPKGFULLNAME" || bee_die "bee_version: not allowed to change the package name from $oPKGFULLNAME to $PKGFULLNAME"
+}
+
 function add_sourcesubdir() {
    print_warning "WARNING: add_sourcesubdir is deprecated in favor of sourcesubdir_append"
    sourcesubdir_append "${@}"
@@ -747,7 +761,6 @@ function save_current_package_variables() {
 
 function extract_new_package_variables() {
     nPKGFULLNAME="${PKGNAME}${PKGEXTRANAME:+_${PKGEXTRANAME}}"
-
     if [ "${oPKGFULLNAME}" != "${PKGFULLNAME}" ] ; then
         if [ "${oPKGFULLNAME}" != "${nPKGFULLNAME}" ] ; then
             print_error "${BEE##*/}: Changing PKGFULLNAME and one of PKGNAME or PKGEXTRANAME is not supported."
@@ -764,10 +777,6 @@ function extract_new_package_variables() {
 
     nPKGFULLVERSION="${PKGVERSION}${PKGEXTRAVERSION:+_${PKGEXTRAVERSION}}"
     if [ "${oPKGFULLVERSION}" != "${PKGFULLVERSION}" ] ; then
-        if [ "${oPKGFULLVERSION}" != "${nPKGFULLVERSION}" ] ; then
-            print_error "${BEE##*/}: Changing PKGFULLVERSION and one of PKGVERSION or PKGEXTRAVERSION is not supported."
-            exit 1
-        fi
         PKGVERSION=${PKGFULLVERSION//_*}
         if [ "$PKGVERSION" = "$PKGFULLVERSION" ] ; then
             PKGEXTRAVERSION=""