[PATCH 2/8] tests/qtest/boot-serial-test: Build command line using GString API

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 tests/qtest/boot-serial-test.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/tests/qtest/boot-serial-test.c b/tests/qtest/boot-serial-test.c
index 3aef3a97a9..fccf706f99 100644
--- a/tests/qtest/boot-serial-test.c
+++ b/tests/qtest/boot-serial-test.c
@@ -226,23 +226,25 @@ static void test_machine(const void *data)
     const testdef_t *test = data;
     g_autofree char *serialtmp = NULL;
     g_autofree char *codetmp = NULL;
-    const char *codeparam = "";
     const uint8_t *code = NULL;
     QTestState *qts;
     int ser_fd;
+    g_autoptr(GString) cmd = g_string_new("");
 
     ser_fd = g_file_open_tmp("qtest-boot-serial-sXXXXXX", &serialtmp, NULL);
     g_assert(ser_fd != -1);
     close(ser_fd);
 
+    g_string_append_printf(cmd, "-M %s ", test->machine);
+    g_string_append(cmd, "-no-shutdown ");
+
     if (test->kernel) {
         code = test->kernel;
-        codeparam = "-kernel";
+        g_string_append(cmd, "-kernel ");
     } else if (test->bios) {
         code = test->bios;
-        codeparam = "-bios";
+        g_string_append(cmd, "-bios ");
     }
-
     if (code) {
         ssize_t wlen;
         int code_fd;
@@ -252,17 +254,22 @@ static void test_machine(const void *data)
         wlen = write(code_fd, code, test->codesize);
         g_assert(wlen == test->codesize);
         close(code_fd);
+        g_string_append_printf(cmd, "%s ", codetmp);
     }
 
+    g_string_append_printf(cmd, "-chardev file,id=serial0,path=%s "
+                                "-serial chardev:serial0 ", serialtmp);
+
     /*
      * Make sure that this test uses tcg if available: It is used as a
      * fast-enough smoketest for that.
      */
-    qts = qtest_initf("%s %s -M %s -no-shutdown "
-                      "-chardev file,id=serial0,path=%s "
-                      "-serial chardev:serial0 -accel tcg -accel kvm %s",
-                      codeparam, code ? codetmp : "", test->machine,
-                      serialtmp, test->extra);
+    g_string_append(cmd, "-accel tcg ");
+    g_string_append(cmd, "-accel kvm ");
+    g_string_append(cmd, test->extra);
+
+    qts = qtest_init(cmd->str);
+
     if (code) {
         unlink(codetmp);
     }
-- 
2.38.1