build: allow setting a custom GIT binary for transparent proxying

Some users can't run a bare 'git' command, due to need for a transparent
proxying solution such as 'tsocks'. This adds an argument to configure to
let users specify such a thing:

  ./configure --with-git="tsocks git"

The submodule script is also updated to give the user a hint about using this
flag, if we fail to checkout modules.

Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

1 files changed, 24 insertions, 5 deletions

diff --git a/scripts/git-submodule.sh b/scripts/git-submodule.sh
index 08932a3..039f782 100755
--- a/scripts/git-submodule.sh
+++ b/scripts/git-submodule.sh
@@ -3,14 +3,27 @@
 # This code is licensed under the GPL version 2 or later.  See
 # the COPYING file in the top-level directory.
 
-set -e
-
 substat=".git-submodule-status"
 
 command=$1
 shift
 modules="$@"
 
+test -z "$GIT" && GIT=git
+
+error() {
+    echo "$0: $*"
+    echo
+    echo "Unable to automatically checkout GIT submodules '$modules'."
+    echo "If you require use of an alternative GIT binary (for example to"
+    echo "enable use of a transparent proxy), then please specify it by"
+    echo "running configure by with the '--with-git' argument. e.g."
+    echo
+    echo " $ ./configure --with-git='tsocks git'"
+    echo
+    exit 1
+}
+
 if test -z "$modules"
 then
     test -e $substat || touch $substat
@@ -27,12 +40,18 @@ case "$command" in
 status)
     test -f "$substat" || exit 1
     trap "rm -f ${substat}.tmp" EXIT
-    git submodule status $modules > "${substat}.tmp"
+    $GIT submodule status $modules > "${substat}.tmp"
+    test $? -ne 0 && error "failed to query git submodule status"
     diff "${substat}" "${substat}.tmp" >/dev/null
     exit $?
     ;;
 update)
-    git submodule update --init $modules 1>/dev/null
-    git submodule status $modules > "${substat}"
+    $GIT submodule update --init $modules 1>/dev/null
+    test $? -ne 0 && error "failed to update modules"
+
+    $GIT submodule status $modules > "${substat}"
+    test $? -ne 0 && error "failed to save git submodule status" >&2
     ;;
 esac
+
+exit 0