Use git describe output for versions

contrib/semver/version.sh

@@ -1,46 +1,5 @@
 #!/bin/sh
 
-# Get the last tag
-TAG=$(git describe --abbrev=0 --tags --match="v[0-9]*\.[0-9]*\.[0-9]*" 2>/dev/null)
-
-# Did getting the tag succeed?
-if [ $? != 0 ] || [ -z "$TAG" ]; then
-  printf -- "unknown"
-  exit 0
-fi
-
-# Get the current branch
-BRANCH=$(git symbolic-ref -q HEAD --short 2>/dev/null)
-
-# Did getting the branch succeed?
-if [ $? != 0 ] || [ -z "$BRANCH" ]; then
-  BRANCH="master"
-fi
-
-# Split out into major, minor and patch numbers
-MAJOR=$(echo $TAG | cut -c 2- | cut -d "." -f 1)
-MINOR=$(echo $TAG | cut -c 2- | cut -d "." -f 2)
-PATCH=$(echo $TAG | cut -c 2- | cut -d "." -f 3)
-
-# Output in the desired format
-if [ $((PATCH)) -eq 0 ]; then
-  printf '%s%d.%d' "$PREPEND" "$((MAJOR))" "$((MINOR))"
-else
-  printf '%s%d.%d.%d' "$PREPEND" "$((MAJOR))" "$((MINOR))" "$((PATCH))"
-fi
-
-# Add the build tag on non-master branches
-if [ "$BRANCH" != "master" ]; then
-  BUILD=$(git rev-list --count $TAG..HEAD 2>/dev/null)
-
-  # Did getting the count of commits since the tag succeed?
-  if [ $? != 0 ] || [ -z "$BUILD" ]; then
-    printf -- "-unknown"
-    exit 0
-  fi
-
-  # Is the build greater than zero?
-  if [ $((BUILD)) -gt 0 ]; then
-      printf -- "-%04d" "$((BUILD))"
-  fi
-fi
+# We'll just use the `git describe` version since it's reasonably
+# easy to refer to a tag or commit using the describe output.
+git describe --match="v[0-9]*\.[0-9]*\.[0-9]*" 2>/dev/null