tools/gitlog2version.sh, tools/semver-compare.sh: fix numeric envvar/CLI arg evaluation for ksh [networkupstools#3055]

...where `[ '' -ge 0 ] ; echo $?` does not report a non-numeric error, but succeeds instead.

Signed-off-by: Jim Klimov <jimklimov+nut@gmail.com>

Author: jimklimov

tools/gitlog2version.sh

@@ -167,7 +167,7 @@ fi
 
 ##############################################################################
 # For tools/semver-compare.sh ($SEMVER_COMPARE):
-if [ "${NUT_VERSION_EXTRA_WIDTH-}" -gt 6 ] 2>/dev/null ; then
+if [ -n "${NUT_VERSION_EXTRA_WIDTH-}" -a "${NUT_VERSION_EXTRA_WIDTH-}" -gt 6 ] 2>/dev/null ; then
     :
 else
     NUT_VERSION_EXTRA_WIDTH=6
@@ -180,7 +180,7 @@ fi
 
 # When padding extra width for e.g. comparisons, is 1.2.3 equal to 1.2.3.0.0?
 # Should we add those ".0" in the end?
-if [ "${NUT_VERSION_MIN_COMPONENTS-}" -ge 0 ] 2>/dev/null ; then
+if [ -n "${NUT_VERSION_MIN_COMPONENTS-}" -a "${NUT_VERSION_MIN_COMPONENTS-}" -ge 0 ] 2>/dev/null ; then
     # A number specified by caller is valid (positive integer)
     :
 else

tools/semver-compare.sh

@@ -28,13 +28,13 @@ LC_ALL=C
 TZ=UTC
 export LANG LC_ALL TZ
 
-if [ "${NUT_VERSION_EXTRA_WIDTH-}" -gt 6 ] 2>/dev/null ; then
+if [ -n "${NUT_VERSION_EXTRA_WIDTH-}" -a "${NUT_VERSION_EXTRA_WIDTH-}" -gt 6 ] 2>/dev/null ; then
     :
 else
     NUT_VERSION_EXTRA_WIDTH=6
 fi
 
-if [ "${NUT_VERSION_MIN_COMPONENTS-}" -ge 0 ] 2>/dev/null ; then
+if [ -n "${NUT_VERSION_MIN_COMPONENTS-}" -a "${NUT_VERSION_MIN_COMPONENTS-}" -ge 0 ] 2>/dev/null ; then
     # A number specified by caller is valid (positive integer)
     :
 else
@@ -189,14 +189,14 @@ EOF
             exit 0
             ;;
         --width|-w)
-            if [ "$2" -ge 6 ]; then
+            if [ -n "$2" -a "$2" -ge 6 ]; then
                 NUT_VERSION_EXTRA_WIDTH="$2"
             fi
             # FIXME: "else" and error handling vs number too small and ignored?
             shift
             ;;
         --min-components)
-            if [ "$2" -ge 0 ]; then
+            if [ -n "$2" -a "$2" -ge 0 ]; then
                 NUT_VERSION_MIN_COMPONENTS="$2"
             fi
             # FIXME: "else" and error handling vs number too small and ignored?