Add a simple method to run regression tests

This is only useful when building shared libraries.  This allows us to
run our tests against newer libraries when the time comes.  Simply do
this:

    OPENSSL_REGRESSION=/other/OpenSSL/build/tree make test

($OPENSSL_REGRESSION *must* be an absolute path)

Reviewed-by: Andy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5619)

diff --git a/util/shlib_wrap.sh.in b/util/shlib_wrap.sh.in
index 27a1e513c80c6e40298a40f9639001dfde735d35..6c115ba7256c9400b237dd28184e4a19ca5eb549 100755 (executable)
--- a/util/shlib_wrap.sh.in
+++ b/util/shlib_wrap.sh.in
@@ -1,5 +1,25 @@
 #!/bin/sh
 
+# To test this OpenSSL version's applications against another version's
+# shared libraries, simply set
+#
+#     OPENSSL_REGRESSION=/path/to/other/OpenSSL/build/tree
+if [ -n "$OPENSSL_REGRESSION" ]; then
+    shlibwrap="$OPENSSL_REGRESSION/util/shlib_wrap.sh"
+    if [ -x "$shlibwrap" ]; then
+        # We clear OPENSSL_REGRESSION to avoid a loop, should the shlib_wrap.sh
+        # we exec also support that mechanism...
+        OPENSSL_REGRESSION= exec "$shlibwrap" "$@"
+    else
+        if [ -f "$shlibwrap" ]; then
+            echo "Not permitted to run $shlibwrap" >&2
+        else
+            echo "No $shlibwrap, perhaps OPENSSL_REGRESSION isn't properly set?" >&2
+        fi
+        exit 1
+    fi
+fi
+
 [ $# -ne 0 ] || set -x         # debug mode without arguments:-)
 
 THERE="`echo $0 | sed -e 's|[^/]*$||' 2>/dev/null`.."