[XEN PATCH v2] build: add --full to version.sh to guess $(XEN_FULLVERSION)

[Anthony PERARD <anthony.perard@xxxxxxxxxx>]

Running $(MAKE) like that in a $(shell ) while parsing the Makefile
doesn't work reliably. In some case, make will complain with
"jobserver unavailable: using -j1.  Add '+' to parent make rule.".
Also, it isn't possible to distinguish between the output produced by
the target "xenversion" and `make`'s own output.

Instead of running make, this patch "improve" `version.sh` to try to
guess the output of `make xenversion`.

In order to have version.sh works in more scenario, it will use
XEN_EXTRAVERSION and XEN_VENDORVERSION from the environment when
present. As for the cases were those two variables are overridden by a
make command line arguments, we export them when invoking version.sh
via a new $(XEN_FULLVERSION) macro.

That should hopefully get us to having ./version.sh returning the same
value that `make xenversion` would.

This fix GitLab CI's build job "debian-unstable-gcc-arm64".

Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx>
---
v2:
- use $(SHELL) to execute ./version.sh
- get XEN_EXTRAVERSION from the environment if exist
- use XEN_VENDORVERSION when exist in the environment
- introduce a new macro $(XEN_FULLVERSION) whose jobs is to export
  $(XEN_EXTRAVERSION) and $(XEN_VENDORVERSION) in cases where those
  are overridden by command line argument of make.
  (we can't just use make's "export" because it doesn't work when
  parsing the makefile which is when $(shell ) get's executed for
  POLICY_FILENAME, so it wouldn't work when running `make -C
  tools/flask/policy XEN_VENDORVERSION=-os`.)
---
 tools/Rules.mk                     |  5 +++++
 tools/flask/policy/Makefile.common |  2 +-
 version.sh                         | 18 +++++++++++++++++-
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/tools/Rules.mk b/tools/Rules.mk
index 2907ed2d3972..b022da3336c4 100644
--- a/tools/Rules.mk
+++ b/tools/Rules.mk
@@ -6,6 +6,11 @@ all:
 -include $(XEN_ROOT)/config/Tools.mk
 include $(XEN_ROOT)/Config.mk
 
+XEN_FULLVERSION=$(shell env \
+    XEN_EXTRAVERSION=$(XEN_EXTRAVERSION) \
+    XEN_VENDORVERSION=$(XEN_VENDORVERSION) \
+    $(SHELL) $(XEN_ROOT)/version.sh --full $(XEN_ROOT)/xen/Makefile)
+
 export _INSTALL := $(INSTALL)
 INSTALL = $(XEN_ROOT)/tools/cross-install
 
diff --git a/tools/flask/policy/Makefile.common 
b/tools/flask/policy/Makefile.common
index bea5ba4b6a40..e5ed58200e75 100644
--- a/tools/flask/policy/Makefile.common
+++ b/tools/flask/policy/Makefile.common
@@ -35,7 +35,7 @@ OUTPUT_POLICY ?= $(BEST_POLICY_VER)
 #
 ########################################
 
-POLICY_FILENAME = $(FLASK_BUILD_DIR)/xenpolicy-$(shell $(MAKE) -C 
$(XEN_ROOT)/xen xenversion --no-print-directory)
+POLICY_FILENAME = $(FLASK_BUILD_DIR)/xenpolicy-$(XEN_FULLVERSION)
 POLICY_LOADPATH = /boot
 
 # List of policy versions supported by the hypervisor
diff --git a/version.sh b/version.sh
index e894ee7e0469..c6a5692c1982 100755
--- a/version.sh
+++ b/version.sh
@@ -1,5 +1,21 @@
 #!/bin/sh
 
+opt_full=false
+while [ $# -gt 1 ]; do
+    case "$1" in
+        --full) opt_full=true ;;
+        *) break ;;
+    esac
+    shift
+done
+
 MAJOR=`grep "export XEN_VERSION" $1 | sed 's/.*=//g' | tr -s " "`
 MINOR=`grep "export XEN_SUBVERSION" $1 | sed 's/.*=//g' | tr -s " "`
-printf "%d.%d" $MAJOR $MINOR
+
+if $opt_full; then
+    extraversion=$(grep "export XEN_EXTRAVERSION" $1 | sed 's/^.* ?=\s\+//; 
s/\$([^)]*)//g; s/ //g')
+    : ${XEN_EXTRAVERSION:=${extraversion}${XEN_VENDORVERSION}}
+else
+    unset XEN_EXTRAVERSION
+fi
+printf "%d.%d%s" $MAJOR $MINOR $XEN_EXTRAVERSION
-- 
Anthony PERARD