Subject: Re: [PATCH] mnt: remove unneeded conversion to bool
To:     Joe Perches <joe@perches.com>, davidcomponentone@gmail.com,
        shuah@kernel.org
Cc:     linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org,
        Yang Guang <yang.guang5@zte.com.cn>,
        Zeal Robot <zealci@zte.com.cn>,
        Shuah Khan <skhan@linuxfoundation.org>
References: <3a7435c9e7e7aa8f24d22fd576ce912eb0540272.1637737086.git.yang.guang5@zte.com.cn>
 <07f4ba23-cf4c-6817-f7a4-5428f35d966c@linuxfoundation.org>
 <983ee57718a6e5838f79be96b7f7efc638177f76.camel@perches.com>
From:   Shuah Khan <skhan@linuxfoundation.org>
Message-ID: <eef8e264-7cf7-8747-867e-b40c9f180d0d@linuxfoundation.org>
Date:   Fri, 3 Dec 2021 17:24:31 -0700
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On 12/3/21 12:50 PM, Joe Perches wrote:
> On Fri, 2021-12-03 at 11:26 -0700, Shuah Khan wrote:
>> On 11/24/21 5:56 PM, davidcomponentone@gmail.com wrote:
>>> From: Yang Guang <yang.guang5@zte.com.cn>
>>>
>>> The coccinelle report
>>> ./tools/testing/selftests/mount/unprivileged-remount-test.c:285:54-59:
>>> WARNING: conversion to bool not needed here
>>> ./tools/testing/selftests/mount/unprivileged-remount-test.c:207:54-59:
>>> WARNING: conversion to bool not needed here
>>> Relational and logical operators evaluate to bool,
>>> explicit conversion is overly verbose and unneeded.
>>>
>>> Reported-by: Zeal Robot <zealci@zte.com.cn>
>>> Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
>>> ---
>>>    tools/testing/selftests/mount/unprivileged-remount-test.c | 4 ++--
>>>    1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/tools/testing/selftests/mount/unprivileged-remount-test.c b/tools/testing/selftests/mount/unprivileged-remount-test.c
>>> index 584dc6bc3b06..d2917054fe3a 100644
>>> --- a/tools/testing/selftests/mount/unprivileged-remount-test.c
>>> +++ b/tools/testing/selftests/mount/unprivileged-remount-test.c
>>> @@ -204,7 +204,7 @@ bool test_unpriv_remount(const char *fstype, const char *mount_options,
>>>    		if (!WIFEXITED(status)) {
>>>    			die("child did not terminate cleanly\n");
>>>    		}
>>> -		return WEXITSTATUS(status) == EXIT_SUCCESS ? true : false;
>>> +		return WEXITSTATUS(status) == EXIT_SUCCESS;
>>>    	}
>>>    
>>>    	create_and_enter_userns();
>>> @@ -282,7 +282,7 @@ static bool test_priv_mount_unpriv_remount(void)
>>>    		if (!WIFEXITED(status)) {
>>>    			die("child did not terminate cleanly\n");
>>>    		}
>>> -		return WEXITSTATUS(status) == EXIT_SUCCESS ? true : false;
>>> +		return WEXITSTATUS(status) == EXIT_SUCCESS;
>>>    	}
>>>    
>>>    	orig_mnt_flags = read_mnt_flags(orig_path);
>>>
>>
>> This change doesn't look right. WEXITSTATUS(status) return could be
>>> 1 or 0 or negative.
> 
> The change is at least logically correct.
> 
> And isn't WEXITSTATUS range limited from 0->255 ?
> 
> https://www.gnu.org/software/libc/manual/html_node/Exit-Status.html
> 

You are right. In any case, I don't see any value in changing the current
logic. The way it is coded is cryptic enough :)

thanks,
-- Shuah