btrfs-progs: tests: add support to test the .static binaries

Testing the statically built binaries is not straightforward, add a
convenient way to do that:

  $ make TEST_FLAVOR=static

There should be no difference in the test results.

Signed-off-by: David Sterba <dsterba@suse.com>

tests/Makefile

@@ -3,6 +3,7 @@
 #   TEST=GLOB      run test(s) from directories matching GLOB
 #   TEST_LOG=tty   print name of a command run via the execution helpers
 #   TEST_LOG=dump  dump testing log file when a test fails
+#   TEST_FLAVOR    test build flavor: dynamic (default), static
 #
 #   TOP=path       test binaries from the given path
 

tests/README.md

@@ -132,6 +132,9 @@ occurs, possibly allowing to continue interactively debugging.
 
 * `TEST_LOG=dump` -- dump the entire testing log when a test fails
 
+* `TEST_FLAVOR` -- run binaries of specified flavor, which is dynamic build by
+  default, or *static* using all the build binaries with *.static* suffix
+
 * `TEST_ENABLE_OVERRIDE` -- defined either as make arguments or via
   `tests/common.local` to enable additional arguments to some commands, using
   the variable(s) below (default: false, enable by setting to 'true')

tests/common

@@ -198,7 +198,11 @@ expand_command()
 		if [ $i -eq $ins -a ! -z "$spec" ]; then
 			cmd_array+=("$spec")
 		fi
-		cmd_array+=("${!i}")
+		if [ $i -eq $command_index -a "$TEST_FLAVOR" = 'static' ]; then
+			cmd_array+=("${!i}".static)
+		else
+			cmd_array+=("${!i}")
+		fi
 	done
 }
 
@@ -376,8 +380,12 @@ check_prereq()
 		fi
 		;;
 	*)
-		if ! [ -f "$TOP/$1" ]; then
-			_fail "Failed prerequisites: $TOP/$1";
+		bin="$TOP/$1"
+		if [ "$TEST_FLAVOR" = 'static' ]; then
+			bin="${bin}.static"
+		fi
+		if ! [ -f "$bin"  ]; then
+			_fail "Failed prerequisites: $bin";
 		fi
 		;;
 	esac