Build: Append git revision hash to version

Append the git revision hash to the libsigrok package version,
unless HEAD exactly matches a release tag.  Note that this does
not affect the version known to autoconf -- e.g. source tarballs
created by make dist will not receive a revision suffix.

Changes to git HEAD automatically trigger a reconfiguration.
Uncommitted changes do not, which is why I left out the -dirty
suffix.

diff --git a/configure.ac b/configure.ac
index 68e642f20b13948c9280c9efabaa68a9032c9f47..a5a309b10a12bad7ced14e86902043760a78df69 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -25,10 +25,9 @@ AC_PREREQ([2.63])
 m4_define([sr_package_version_major], [0])
 m4_define([sr_package_version_minor], [4])
 m4_define([sr_package_version_micro], [0])
-m4_define([sr_package_version_suffix], [-git])
-m4_define([sr_package_version], [sr_package_version_major.sr_package_version_minor.sr_package_version_micro[]sr_package_version_suffix])
 
-AC_INIT([libsigrok], [sr_package_version], [sigrok-devel@lists.sourceforge.net],
+AC_INIT([libsigrok], [sr_package_version_major.sr_package_version_minor.sr_package_version_micro],
+       [sigrok-devel@lists.sourceforge.net],
        [libsigrok], [http://www.sigrok.org])
 AC_CONFIG_HEADERS([config.h include/libsigrok/version.h])
 AC_CONFIG_MACRO_DIR([autostuff])
@@ -66,7 +65,25 @@ LT_INIT
 # We require at least 0.22, as "Requires.private" behaviour changed there.
 PKG_PROG_PKG_CONFIG([0.22])
 
-AC_SUBST([SR_PACKAGE_VERSION], [sr_package_version])
+CONFIG_STATUS_DEPENDENCIES=
+SR_PACKAGE_VERSION="AC_PACKAGE_VERSION"
+
+# Check if we can get revision information from git.
+sr_head=`git -C "$srcdir" rev-parse --verify --short HEAD 2>&AS_MESSAGE_LOG_FD`
+
+AS_IF([test "$?" -eq 0 && test -n "$sr_head"], [
+       CONFIG_STATUS_DEPENDENCIES='$(top_srcdir)/.git/HEAD'
+       sr_head_name=`git -C "$srcdir" rev-parse --symbolic-full-name HEAD 2>&AS_MESSAGE_LOG_FD`
+       AS_IF([test "$?" -eq 0 && test -f "$srcdir/.git/$sr_head_name"],
+               [CONFIG_STATUS_DEPENDENCIES="$CONFIG_STATUS_DEPENDENCIES \$(top_srcdir)/.git/$sr_head_name"])
+
+       # Append the revision hash unless we are exactly on a tagged release.
+       git -C "$srcdir" describe --match 'AC_PACKAGE_NAME-AC_PACKAGE_VERSION' \
+               --exact-match >&AS_MESSAGE_LOG_FD 2>&AS_MESSAGE_LOG_FD \
+       || SR_PACKAGE_VERSION="$SR_PACKAGE_VERSION-git-$sr_head"
+])
+AC_SUBST([CONFIG_STATUS_DEPENDENCIES])
+AC_SUBST([SR_PACKAGE_VERSION])
 
 AC_DEFINE([SR_PACKAGE_VERSION_MAJOR], [sr_package_version_major], [.])
 AC_DEFINE([SR_PACKAGE_VERSION_MINOR], [sr_package_version_minor], [.])