ci/package_core: generate SemVer-compatible core version

Add the get_core_version.sh script to generate a SemVer-compatible
version number for the core, based on Git tags. Update package_core.sh
and gen_package_index_json.sh to use it.

Signed-off-by: Luca Burelli <[email protected]>

Author: pillo79

.github/workflows/package_core.yml

@@ -35,6 +35,7 @@ jobs:
           yes | ./extra/bootstrap.sh -o=--filter=tree:0
           echo "CORE_HASH=$(git describe --always)" >> "$GITHUB_ENV"
           echo "ALL_BOARD_DATA=$(extra/get_board_details.sh | jq -c 'sort_by(.variant)')" >> "$GITHUB_ENV"
+          echo "## Building \`$(extra/get_core_version.sh)\`" >> "$GITHUB_STEP_SUMMARY"
 
       - name: Map output packages
         # needs the above env vars to be usable

extra/gen_package_index_json.sh

@@ -16,7 +16,7 @@ fi
 
 JSON_TEMPLATE="extra/zephyr-core-template.json"
 cat $JSON_TEMPLATE | sed \
-	-e "s/__CORE_TAG__/$CORE_TAG/" \
+	-e "s/__CORE_TAG__/$(extra/get_core_version.sh)/" \
 	-e "s/__ARTIFACT_FILE__/$(basename $ARTIFACT_FILE)/" \
 	-e "s/__ARTIFACT_HASH__/$(sha256sum $ARTIFACT_FILE | awk '{print $1}')/" \
 	-e "s/__ARTIFACT_SIZE__/$(stat -c %s $ARTIFACT_FILE)/" | jq .

extra/get_core_version.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+
+# This script generates a SemVer-compatible version number based on Git tags.
+#
+# If the current commit is tagged, it returns that version. If not, it
+# generates a version string based on the next patch number and the current
+# commit hash.
+#
+# If the tag is a simple "<maj>.<min>.<patch>", git describe will output:
+#
+#     <maj>.<min>.<patch>-<number-of-commits-since-tag>-g<commit-hash-dirty>
+#
+# The regexp splits the patch number, awk converts the tokens to:
+#
+#     <maj>.<min>.<next-patch>-0.dev+<commit-hash-dirty>
+#
+# If the tag refers to a pre-release, like "<maj>.<min>.<patch>-<extra-stuff>",
+# sed will output a total of 4 arguments and the format of the final awk output
+# will be:
+#
+#     <maj>.<min>.<patch>-<extra-stuff>-0.dev+<commit-hash-dirty>
+#
+# These are among the lowest possible SemVer versions greater than the last
+# tagged version.
+#
+# If there are no tags at all (for example when run in a fork etc), it defaults
+# to "9.9.9-<date>+<commit-hash-dirty>".
+
+VERSION=$(git describe --tags --exact-match 2>/dev/null)
+if [ -z "$VERSION" ]; then
+	VERSION=$(git describe --tags --dirty 2>/dev/null |
+		sed 's/\.\([[:digit:]]\+\)\(-.*\)*-[[:digit:]]\+-g/ \1 \2 /' |
+		awk '{ if (NF==3) { print $1 "." ($2+1) "-0.dev+" $3 } else { print $1 "." $2 $3 "-0.dev+" $4 }}')
+	if [ -z "$VERSION" ]; then
+		VERSION="9.9.9-$(date '+%Y%m%d-%H%M%S')+$(git describe --always --dirty)"
+	fi
+fi
+echo $VERSION

extra/package_core.sh

@@ -18,7 +18,8 @@ OUTPUT_FILE=${2:-distrib/${PACKAGE}-${VERSION}.tar.bz2}
 
 # create a temporary platform.txt file with the correct version
 TEMP_PLATFORM=$(mktemp -p . | sed 's/\.\///')
-sed -e "s/^version=.*/version=${VERSION}/" platform.txt > ${TEMP_PLATFORM}
+cat platform.txt > ${TEMP_PLATFORM}
+sed -ie "s/^version=.*/version=$(extra/get_core_version.sh)/" ${TEMP_PLATFORM}
 
 declutter_file() {
 	[ -f "$1" ] || return 0