zdtm: add ability to set id of a test proccess

It's just easy for debugging
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

test/zdtm/lib/test.c

@@ -30,11 +30,13 @@ static pid_t master_pid = 0;
 int proc_id = 0;
 static int proc_id_cur = 0;
 
-int test_fork() {
-	proc_id_cur++;
+int test_fork_id(int id)
+{
 	pid_t pid = fork();
+	if (id < 0)
+		id = ++proc_id_cur;
 	if (pid == 0)
-		proc_id = proc_id_cur;
+		proc_id = id;
 	return pid;
 }
 

test/zdtm/lib/zdtmtst.h

@@ -12,7 +12,8 @@ extern void test_init_ns(int argc, char **argv, unsigned long clone_flags, int (
 #endif
 
 /*wrapper for fork: init log offset*/
-extern int test_fork();
+#define test_fork() test_fork_id(-1)
+extern int test_fork_id(int id);
 /* finish setting up the test, write out pid file, and go to background */
 extern void test_daemon(void);
 /* store a message to a static buffer */