configure: replace --enable/disable-git-update with --with-git-submodules

Replace the --enable-git-update and --disable-git-update configure params
with the param --with-git-submodules=(update|validate|ignore) to
allow 3 options for building from a git repo.

This is needed because downstream packagers, e.g. Debian, Ubuntu, etc,
also keep the source code in git, but do not want to enable the
'git_update' mode; with the current code, that's not possible even
if the downstream package specifies --disable-git-update.

The previous parameters are deprecated but still available; the
--enable-git-update parameter maps to --with-git-submodules=update and
--disable-git-update parameter maps to --with-git-submodules=validate.

The configure script behavior is slightly modified, where previously
the dtc, capstone, and slirp submodules were not validated when
--disable-git-update was specified (but were updated with git-update
enabled), now they are validated when using --with-git-submodules=validate
and are only ignored when using --with-git-submodules=ignore.

Signed-off-by: Dan Streetman <ddstreet@canonical.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

3 files changed, 66 insertions, 43 deletions

diff --git a/Makefile b/Makefile
index 291ea19f2e..b0dff73904 100644
--- a/Makefile
+++ b/Makefile
@@ -47,30 +47,10 @@ git-submodule-update:
 Makefile: .git-submodule-status
 
 .PHONY: git-submodule-update
-
-git_module_status := $(shell \
-  cd '$(SRC_PATH)' && \
-  GIT="$(GIT)" ./scripts/git-submodule.sh status $(GIT_SUBMODULES); \
-  echo $$?; \
-)
-
-ifeq (1,$(git_module_status))
-ifeq (no,$(GIT_UPDATE))
 git-submodule-update:
 	$(call quiet-command, \
-            echo && \
-            echo "GIT submodule checkout is out of date. Please run" && \
-            echo "  scripts/git-submodule.sh update $(GIT_SUBMODULES)" && \
-            echo "from the source directory checkout $(SRC_PATH)" && \
-            echo && \
-            exit 1)
-else
-git-submodule-update:
-	$(call quiet-command, \
-          (cd $(SRC_PATH) && GIT="$(GIT)" ./scripts/git-submodule.sh update $(GIT_SUBMODULES)), \
-          "GIT","$(GIT_SUBMODULES)")
-endif
-endif
+		(GIT="$(GIT)" "$(SRC_PATH)/scripts/git-submodule.sh" $(GIT_SUBMODULES_ACTION) $(GIT_SUBMODULES)), \
+		"GIT","$(GIT_SUBMODULES)")
 
 # 0. ensure the build tree is okay
 
diff --git a/configure b/configure
index 87de49e2c2..8fc59848b2 100755
--- a/configure
+++ b/configure
@@ -254,12 +254,12 @@ gdb_bin=$(command -v "gdb-multiarch" || command -v "gdb")
 
 if test -e "$source_path/.git"
 then
-    git_update=yes
+    git_submodules_action="update"
     git_submodules="ui/keycodemapdb"
     git_submodules="$git_submodules tests/fp/berkeley-testfloat-3"
     git_submodules="$git_submodules tests/fp/berkeley-softfloat-3"
 else
-    git_update=no
+    git_submodules_action="ignore"
     git_submodules=""
 
     if ! test -f "$source_path/ui/keycodemapdb/README"
@@ -1508,9 +1508,16 @@ for opt do
   ;;
   --with-git=*) git="$optarg"
   ;;
-  --enable-git-update) git_update=yes
+  --enable-git-update)
+      git_submodules_action="update"
+      echo "--enable-git-update deprecated, use --with-git-submodules=update"
   ;;
-  --disable-git-update) git_update=no
+  --disable-git-update)
+      git_submodules_action="validate"
+      echo "--disable-git-update deprecated, use --with-git-submodules=validate"
+  ;;
+  --with-git-submodules=*)
+      git_submodules_action="$optarg"
   ;;
   --enable-debug-mutex) debug_mutex=yes
   ;;
@@ -1566,6 +1573,21 @@ for opt do
   esac
 done
 
+case $git_submodules_action in
+    update|validate)
+        if test ! -e "$source_path/.git"; then
+            echo "ERROR: cannot $git_submodules_action git submodules without .git"
+            exit 1
+        fi
+    ;;
+    ignore)
+    ;;
+    *)
+        echo "ERROR: invalid --with-git-submodules= value '$git_submodules_action'"
+        exit 1
+    ;;
+esac
+
 libdir="${libdir:-$prefix/lib}"
 libexecdir="${libexecdir:-$prefix/libexec}"
 includedir="${includedir:-$prefix/include}"
@@ -1710,6 +1732,9 @@ Advanced options (experts only):
   --ninja=NINJA            use specified ninja [$ninja]
   --smbd=SMBD              use specified smbd [$smbd]
   --with-git=GIT           use specified git [$git]
+  --with-git-submodules=update   update git submodules (default if .git dir exists)
+  --with-git-submodules=validate fail if git submodules are not up to date
+  --with-git-submodules=ignore   do not update or check git submodules (default if no .git dir)
   --static                 enable static build [$static]
   --mandir=PATH            install man pages in PATH
   --datadir=PATH           install firmware in PATH/$qemu_suffix
@@ -1926,7 +1951,7 @@ python="$python -B"
 if test -z "$meson"; then
     if test "$explicit_python" = no && has meson && version_ge "$(meson --version)" 0.55.3; then
         meson=meson
-    elif test -e "${source_path}/.git" && test $git_update = 'yes' ; then
+    elif test $git_submodules_action != 'ignore' ; then
         meson=git
     elif test -e "${source_path}/meson/meson.py" ; then
         meson=internal
@@ -1994,7 +2019,7 @@ fi
 # Consult white-list to determine whether to enable werror
 # by default.  Only enable by default for git builds
 if test -z "$werror" ; then
-    if test -e "$source_path/.git" && \
+    if test "$git_submodules_action" != "ignore" && \
         { test "$linux" = "yes" || test "$mingw32" = "yes"; }; then
         werror="yes"
     else
@@ -3550,7 +3575,7 @@ fi
 case "$fdt" in
   auto | enabled | internal)
     # Simpler to always update submodule, even if not needed.
-    if test -e "${source_path}/.git" && test $git_update = 'yes' ; then
+    if test "$git_submodules_action" != "ignore"; then
       git_submodules="${git_submodules} dtc"
     fi
     ;;
@@ -4264,7 +4289,7 @@ fi
 case "$capstone" in
   auto | enabled | internal)
     # Simpler to always update submodule, even if not needed.
-    if test -e "${source_path}/.git" && test $git_update = 'yes' ; then
+    if test "$git_submodules_action" != "ignore"; then
       git_submodules="${git_submodules} capstone"
     fi
     ;;
@@ -5211,7 +5236,7 @@ fi
 case "$slirp" in
   auto | enabled | internal)
     # Simpler to always update submodule, even if not needed.
-    if test -e "${source_path}/.git" && test $git_update = 'yes' ; then
+    if test "$git_submodules_action" != "ignore"; then
       git_submodules="${git_submodules} slirp"
     fi
     ;;
@@ -5385,7 +5410,7 @@ if test "$cpu" = "s390x" ; then
     roms="$roms s390-ccw"
     # SLOF is required for building the s390-ccw firmware on s390x,
     # since it is using the libnet code from SLOF for network booting.
-    if test -e "${source_path}/.git" ; then
+    if test "$git_submodules_action" != "ignore"; then
       git_submodules="${git_submodules} roms/SLOF"
     fi
   fi
@@ -5423,8 +5448,8 @@ else
     cxx=
 fi
 
-if test $git_update = 'yes' ; then
-    (cd "${source_path}" && GIT="$git" "./scripts/git-submodule.sh" update "$git_submodules")
+if !(GIT="$git" "$source_path/scripts/git-submodule.sh" "$git_submodules_action" "$git_submodules"); then
+    exit 1
 fi
 
 config_host_mak="config-host.mak"
@@ -5435,7 +5460,7 @@ echo >> $config_host_mak
 echo all: >> $config_host_mak
 echo "GIT=$git" >> $config_host_mak
 echo "GIT_SUBMODULES=$git_submodules" >> $config_host_mak
-echo "GIT_UPDATE=$git_update" >> $config_host_mak
+echo "GIT_SUBMODULES_ACTION=$git_submodules_action" >> $config_host_mak
 
 echo "ARCH=$ARCH" >> $config_host_mak
 
diff --git a/scripts/git-submodule.sh b/scripts/git-submodule.sh
index 65ed877aef..e225d3a963 100755
--- a/scripts/git-submodule.sh
+++ b/scripts/git-submodule.sh
@@ -9,9 +9,14 @@ command=$1
 shift
 maybe_modules="$@"
 
+# if --with-git-submodules=ignore, do nothing
+test "$command" = "ignore" && exit 0
+
 test -z "$GIT" && GIT=git
 
-error() {
+cd "$(dirname "$0")/.."
+
+update_error() {
     echo "$0: $*"
     echo
     echo "Unable to automatically checkout GIT submodules '$modules'."
@@ -24,7 +29,7 @@ error() {
     echo "Alternatively you may disable automatic GIT submodule checkout"
     echo "with:"
     echo
-    echo " $ ./configure --disable-git-update"
+    echo " $ ./configure --with-git-submodules=validate"
     echo
     echo "and then manually update submodules prior to running make, with:"
     echo
@@ -33,6 +38,19 @@ error() {
     exit 1
 }
 
+validate_error() {
+    if test "$1" = "validate"; then
+        echo "GIT submodules checkout is out of date, and submodules"
+        echo "configured for validate only. Please run"
+        echo "  scripts/git-submodule.sh update $maybe_modules"
+        echo "from the source directory or call configure with"
+        echo "  --with-git-submodules=update"
+        echo "To disable GIT submodules validation, use"
+        echo "  --with-git-submodules=ignore"
+    fi
+    exit 1
+}
+
 modules=""
 for m in $maybe_modules
 do
@@ -52,18 +70,18 @@ then
 fi
 
 case "$command" in
-status)
+status|validate)
     if test -z "$maybe_modules"
     then
-         test -s ${substat} && exit 1 || exit 0
+         test -s ${substat} && validate_error "$command" || exit 0
     fi
 
-    test -f "$substat" || exit 1
+    test -f "$substat" || validate_error "$command"
     for module in $modules; do
         CURSTATUS=$($GIT submodule status $module)
         OLDSTATUS=$(cat $substat | grep $module)
         if test "$CURSTATUS" != "$OLDSTATUS"; then
-            exit 1
+            validate_error "$command"
         fi
     done
     exit 0
@@ -76,10 +94,10 @@ update)
     fi
 
     $GIT submodule update --init $modules 1>/dev/null
-    test $? -ne 0 && error "failed to update modules"
+    test $? -ne 0 && update_error "failed to update modules"
 
     $GIT submodule status $modules > "${substat}"
-    test $? -ne 0 && error "failed to save git submodule status" >&2
+    test $? -ne 0 && update_error "failed to save git submodule status" >&2
     ;;
 esac