Add version.sh

Author: postgres-dev

version.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+
+# Output the program version based on the state of the repository (source code
+# and tags).
+# Tags must be in the form of
+# x.y.z, e.g. 3.1.0
+# or
+# x.y.z-<prerelease part (alpha, alpha2, beta etc.)>, e.g. 3.1.0-beta2
+# If the tag consists only of the version number (i.e. it doesn't contain a
+# prerelease part) and this number is equal to the version in the header file
+# then the version is considered a release and no additional version data is
+# appended to it by default (but can be forced by "-p" and "-r" command line
+# arguments). Otherwise, provided Git is available, the prerelease part and Git
+# revision are automatically added to the version.
+
+cd `dirname "$0"`
+
+while getopts p:r:sv: opt; do
+  case $opt in
+    p) prerelease=$OPTARG;;
+    r) revision=$OPTARG;;
+    s) ID=semver;;
+    v) version=$OPTARG;;
+  esac
+done
+
+if [ -z "$ID" ]; then
+  . /etc/os-release
+fi
+case $ID in
+  altlinux | astra | debian | ubuntu)
+    # The only scheme that properly sorts metadata and prerelease fields is
+    # when the both are specified after a '~'
+    presep='~'; metasep='~';;
+  centos | opensuse-leap | redos)
+    presep='~'; metasep=^;;
+  *)  # semver
+    presep=-; metasep=+
+esac
+
+if [ -z "$version" ]; then
+  version=`grep '#define PROGRAM_VERSION' src/pg_probackup.h | cut -f 2 | tr -d '"'`
+fi
+
+if which git >/dev/null 2>&1; then
+  tag=`git describe --tags 2> /dev/null`
+  # Shallow cloned repository may not have tags
+  if [ -z "$prerelease" -a "$tag" ]; then
+    f1=`cut -d - -f 1 <<< $tag`
+    f2=`cut -d - -f 2 <<< $tag`
+    # Append the prerelease part only if the tag refers to the current version
+    # Assume that the prerelease part contains letters
+    if [ $f1 = $version ] && expr "$f2" : "[1-9]*[a-zA-Z]" 1>/dev/null; then
+      prerelease="$f2"
+    fi
+  fi
+  if [ -z "$revision" ]; then
+    revision=g`git rev-parse --short HEAD`
+  fi
+fi
+
+out=$version${prerelease:+$presep$prerelease}
+if [ "$tag" != $version -a "$revision" ]; then
+  out=$out$metasep`date +%Y%m%d`$revision
+fi
+
+echo $out