build: Capture git describe on build if available, add to --version

Many projects do this, and it really helps debugging to know the
exact hash.

(Of course this is broken in traditional rpm builds from a tarball,
 and rpmdistro-gitoverlay injects it into the Version field,
 but it will help me for vmcheck debugging)

Closes: #584
Approved by: jlebon

Makefile.am

@@ -30,11 +30,14 @@ if ENABLE_GTK_DOC
 SUBDIRS += api-doc
 endif
 
+RPM_OSTREE_GITREV=$(shell if command -v git >/dev/null 2>&1 && test -d $(srcdir)/.git; then git describe --abbrev=42 --tags --always HEAD; fi)
+
 ACLOCAL_AMFLAGS += -I m4 ${ACLOCAL_FLAGS}
 AM_CPPFLAGS += -DDATADIR='"$(datadir)"' \
 	-DLIBEXECDIR='"$(libexecdir)"' \
 	-DLOCALEDIR=\"$(datadir)/locale\" \
         -DRPM_OSTREE_FEATURES='"$(RPM_OSTREE_FEATURES)"' \
+	-DRPM_OSTREE_GITREV='"$(RPM_OSTREE_GITREV)"' \
 	-DGLIB_VERSION_MIN_REQUIRED=GLIB_VERSION_2_40 -DGLIB_VERSION_MAX_ALLOWED=GLIB_VERSION_2_40_
 AM_CFLAGS += -std=gnu11 $(WARN_CFLAGS)
 # bundled libdnf

src/app/main.c

@@ -147,7 +147,10 @@ rpmostree_option_context_parse (GOptionContext *context,
 
   if (opt_version)
     {
-      g_print ("%s\n  %s\n", PACKAGE_STRING, RPM_OSTREE_FEATURES);
+      g_print ("%s", PACKAGE_STRING);
+      if (strlen (RPM_OSTREE_GITREV) > 0)
+        g_print (", git %s", RPM_OSTREE_GITREV);
+      g_print ("\n %s\n", RPM_OSTREE_FEATURES);
       exit (EXIT_SUCCESS);
     }
 

tests/common/libvm.sh

@@ -93,6 +93,9 @@ vm_ssh_wait() {
   while [ $timeout -gt 0 ]; do
     if bootid=$(vm_get_boot_id 2>/dev/null); then
         if [[ $bootid != $old_bootid ]]; then
+            # Display some info per boot
+            vm_rpmostree status
+            vm_rpmostree --version
             return 0
         fi
     fi