Re: [PATCH 04/51] semihosting/arm-compat-semi: Avoid using hardcoded /tmp

[Bin Meng]

On Wed, Aug 31, 2022 at 8:59 PM Marc-André Lureau
<marcandre.lureau@gmail.com> wrote:
>
> Hi
>
> On Wed, Aug 24, 2022 at 1:54 PM Bin Meng <bmeng.cn@gmail.com> wrote:
>>
>> From: Bin Meng <bin.meng@windriver.com>
>>
>> Use g_get_tmp_dir() to get the directory to use for temporary files.
>>
>> Signed-off-by: Bin Meng <bin.meng@windriver.com>
>> ---
>>
>>  semihosting/arm-compat-semi.c | 3 ++-
>>  1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/semihosting/arm-compat-semi.c b/semihosting/arm-compat-semi.c
>> index e741674238..d5e66cc298 100644
>> --- a/semihosting/arm-compat-semi.c
>> +++ b/semihosting/arm-compat-semi.c
>> @@ -503,7 +503,8 @@ void do_common_semihosting(CPUState *cs)
>>          GET_ARG(0);
>>          GET_ARG(1);
>>          GET_ARG(2);
>> -        len = asprintf(&s, "/tmp/qemu-%x%02x", getpid(), (int)arg1 & 0xff);
>> +        len = asprintf(&s, "%s/qemu-%x%02x", g_get_tmp_dir(),
>> +                       getpid(), (int)arg1 & 0xff);
>
>
> This is most likely wrong. I am not familiar with semihosting, but I believe 
> we are implementing tmpnam(), it should return a POSIX filename.

Replacing /tmp with g_get_tmp_dir() is not wrong, correct?

I checked the semihosting spec, it does not mention the file name
should be a POSIX compliant path.
https://developer.arm.com/documentation/dui0058/d/semihosting/semihosting-swis/sys-tmpnam--0x0d-

Certainly this needs a semihosting expert to take a look.

>
>>
>>          if (len < 0) {
>>              common_semi_set_ret(cs, -1);
>>              break;
>> --

Regards,
Bin