test/zdtm.py: add option to specify external criu for test suite

I am regularly running zdtm.py after updating the CRIU rpm to test if
the new rpm still works. Until know I usually did:

-criu_bin = "../criu/criu"
-crit_bin = "../crit/crit"
+criu_bin = "/usr/sbin/criu"
+crit_bin = "/usr/bin/crit"

This commit adds two arguments to zdtm.py:

  --criu-bin CRIU_BIN   Path to criu binary
  --crit-bin CRIT_BIN   Path to crit binary

It still defaults to the old values from above, but can now easily be
changed to the CRIU binary provided by the packaging system.

This change was more complicated than expected which is probably related
to the fact that zdtm restarts itself in namespaces.

v2:
 - rebase
v3:
 - fix errors reported by 'make lint'
Signed-off-by: Adrian Reber <areber@redhat.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

test/zdtm.py

@@ -693,14 +693,12 @@ test_classes = {'zdtm': zdtm_test, 'inhfd': inhfd_test, 'groups': groups_test}
 # CRIU when launched using CLI
 #
 
-criu_bin = "../criu/criu"
-crit_bin = "../crit/crit"
 join_ns_file = '/run/netns/zdtm_netns'
 
 
 class criu_cli:
 	@staticmethod
-	def run(action, args, fault = None, strace = [], preexec = None, nowait = False):
+	def run(action, args, criu_bin, fault = None, strace = [], preexec = None, nowait = False):
 		env = dict(os.environ, ASAN_OPTIONS = "log_path=asan.log:disable_coredump=0:detect_leaks=0")
 
 		if fault:
@@ -782,7 +780,7 @@ class criu_rpc:
 			raise test_fail_exc('RPC for %s required' % arg)
 
 	@staticmethod
-	def run(action, args, fault = None, strace = [], preexec = None, nowait = False):
+	def run(action, args, criu_bin, fault = None, strace = [], preexec = None, nowait = False):
 		if fault:
 			raise test_fail_exc('RPC and FAULT not supported')
 		if strace:
@@ -858,6 +856,8 @@ class criu:
 		self.__lazy_pages_p = None
 		self.__page_server_p = None
 		self.__dump_process = None
+		self.__criu_bin = opts['criu_bin']
+		self.__crit_bin = opts['crit_bin']
 
 	def fini(self):
 		if self.__lazy_migrate:
@@ -952,7 +952,7 @@ class criu:
 
 		ns_last_pid = open("/proc/sys/kernel/ns_last_pid").read()
 
-		ret = self.__criu.run(action, s_args, self.__fault, strace, preexec, nowait)
+		ret = self.__criu.run(action, s_args, self.__criu_bin, self.__fault, strace, preexec, nowait)
 
 		if nowait:
 			os.close(status_fds[1])
@@ -979,7 +979,7 @@ class criu:
 				open("/proc/sys/kernel/ns_last_pid", "w+").write(ns_last_pid)
 				# try again without faults
 				print("Run criu " + action)
-				ret = self.__criu.run(action, s_args, False, strace, preexec)
+				ret = self.__criu.run(action, s_args, self.__criu_bin, False, strace, preexec)
 				grep_errors(os.path.join(__ddir, log))
 				if ret == 0:
 					return
@@ -993,7 +993,7 @@ class criu:
 		if not self.__show_stats:
 			return
 
-		subprocess.Popen([crit_bin, "show",
+		subprocess.Popen([self.__crit_bin, "show",
 				os.path.join(self.__dump_path,
 				str(self.__iter), "stats-%s" % action)]).wait()
 
@@ -1097,12 +1097,13 @@ class criu:
 
 	@staticmethod
 	def check(feature):
-		return criu_cli.run("check", ["-v0", "--feature", feature]) == 0
+		return criu_cli.run("check", ["-v0", "--feature", feature],
+				opts['criu_bin']) == 0
 
 	@staticmethod
 	def available():
-		if not os.access(criu_bin, os.X_OK):
-			print("CRIU binary not built")
+		if not os.access(opts['criu_bin'], os.X_OK):
+			print("CRIU binary not found at %s" % opts['criu_bin'])
 			sys.exit(1)
 
 	def kill(self):
@@ -1574,7 +1575,8 @@ class Launcher:
 		nd = ('nocr', 'norst', 'pre', 'iters', 'page_server', 'sibling', 'stop', 'empty_ns',
 				'fault', 'keep_img', 'report', 'snaps', 'sat', 'script', 'rpc', 'lazy_pages',
 				'join_ns', 'dedup', 'sbs', 'freezecg', 'user', 'dry_run', 'noauto_dedup',
-				'remote_lazy_pages', 'show_stats', 'lazy_migrate')
+				'remote_lazy_pages', 'show_stats', 'lazy_migrate',
+				'criu_bin', 'crit_bin')
 		arg = repr((name, desc, flavor, {d: self.__opts[d] for d in nd}))
 
 		if self.__use_log:
@@ -2116,6 +2118,8 @@ rp.add_argument("--lazy-migrate", help = "restore pages on demand", action = 'st
 rp.add_argument("--remote-lazy-pages", help = "simulate lazy migration", action = 'store_true')
 rp.add_argument("--title", help = "A test suite title", default = "criu")
 rp.add_argument("--show-stats", help = "Show criu statistics", action = 'store_true')
+rp.add_argument("--criu-bin", help = "Path to criu binary", default = '../criu/criu')
+rp.add_argument("--crit-bin", help = "Path to crit binary", default = '../crit/crit')
 
 lp = sp.add_parser("list", help = "List tests")
 lp.set_defaults(action = list_tests)