Re: [PATCH v2 03/11] tests/qtest/boot-serial-test: Build command line using GString API

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

On 20/1/23 09:59, Thomas Huth wrote:
> On 19/01/2023 15.58, Philippe Mathieu-Daudé wrote:
>> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>> ---
>>   tests/qtest/boot-serial-test.c | 23 +++++++++++++++--------
>>   1 file changed, 15 insertions(+), 8 deletions(-)
>>
>> diff --git a/tests/qtest/boot-serial-test.c 
>> b/tests/qtest/boot-serial-test.c
>> index 3a854b0174..92890b409d 100644
>> --- a/tests/qtest/boot-serial-test.c
>> +++ b/tests/qtest/boot-serial-test.c
>> @@ -226,14 +226,17 @@ 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 = "";
>>       QTestState *qts;
>>       int ser_fd;
>> +    g_autoptr(GString) cmd = g_string_new("");
> 
> You could already start with the "-no-shutdown" here.

It is just the matter of knowing the style of the maintainer :)
IIRC Alex prefers starting with an empty "" to avoid future churn
when adding new params (just add new line instead of modify).

I'll use your suggestion if I respin.

> 
>>       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 || test->bios) {
>>           ssize_t wlen;
>>           int code_fd;
>> @@ -243,19 +246,23 @@ static void test_machine(const void *data)
>>           wlen = write(code_fd, test->kernel ? : test->bios, 
>> test->codesize);
>>           g_assert(wlen == test->codesize);
>>           close(code_fd);
>> +        g_string_append_printf(cmd, "%s %s ",
>> +                               test->kernel ? "-kernel " : "-bios ", 
>> codetmp);
>>       }
>> +    g_string_append_printf(cmd, "-chardev file,id=serial0,path=%s "
>> +                                "-serial chardev:serial0 ", serialtmp);
> 
> Why not include this in the initial g_string_append_printf statement 
> already?
> 
>>       /*
>>        * Make sure that this test uses tcg if available: It is used as a
>>        * fast-enough smoketest for that.
>>        */
>> -    qts = qtest_initf("%s %s %s -M %s -no-shutdown "
>> -                      "-chardev file,id=serial0,path=%s "
>> -                      "-serial chardev:serial0 -accel tcg -accel kvm 
>> %s",
>> -                      codeparam,
>> -                      test->kernel ? "-kernel " : test->bios ? "-bios 
>> " : "",
>> -                      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);
> 
> ... and I have to say that this is already quite a lot of code churn, 
> just to get the -accel parameters tweaked in the end.
> 
> Why don't you simply do a single small patch that just replaces the 
> "-accel tcg -accel" part with "%s %s" and add two parameters like this:
> 
>    has_tcg ? "-accel tcg" : "", has_kvm ? "-accel kvm" : ""

I thought it would be simpler when adding HVF support later, KISS,
but I don't mind to change.

Thanks,

Phil.