[PATCH v2] Removed the casts within ngx_memcmp()

[Alex Colomar]

Hello Maxim!

On 11/30/22 05:22, Maxim Dounin wrote:
> Hello!
> 
> Ping.

Sorry, I didn't know you were waiting for my confirmation.

> 
> On Wed, Nov 09, 2022 at 06:03:24PM +0300, Maxim Dounin wrote:
> 
> [...]
> 
>> # HG changeset patch
>> # User Maxim Dounin <mdounin at mdounin.ru>
>> # Date 1668004692 -10800
>> #      Wed Nov 09 17:38:12 2022 +0300
>> # Node ID fc79ea0724a92c1f463625a11ed4cb785cd342b7
>> # Parent  42bc158a47ecb3c2bd0396c723c307c757f2770e
>> Fixed alignment of ngx_memmove()/ngx_movemem() macro definitions.

Makes sense.

>>
>> diff --git a/src/core/ngx_string.h b/src/core/ngx_string.h
>> --- a/src/core/ngx_string.h
>> +++ b/src/core/ngx_string.h
>> @@ -140,8 +140,8 @@ ngx_copy(u_char *dst, u_char *src, size_
>>   #endif
>>   
>>   
>> -#define ngx_memmove(dst, src, n)   (void) memmove(dst, src, n)
>> -#define ngx_movemem(dst, src, n)   (((u_char *) memmove(dst, src, n)) + (n))
>> +#define ngx_memmove(dst, src, n)  (void) memmove(dst, src, n)
>> +#define ngx_movemem(dst, src, n)  (((u_char *) memmove(dst, src, n)) + (n))
>>   
>>   
>>   /* msvc and icc7 compile memcmp() to the inline loop */
>> # HG changeset patch
>> # User Maxim Dounin <mdounin at mdounin.ru>
>> # Date 1668005196 -10800
>> #      Wed Nov 09 17:46:36 2022 +0300
>> # Node ID 5269880f00df1e5ae08299165ec43435b759c5a3
>> # Parent  fc79ea0724a92c1f463625a11ed4cb785cd342b7
>> Removed casts from ngx_memcmp() macro.
>>
>> Casts are believed to be not needed, since memcmp() has "const void *"
>> arguments since introduction of the "void" type in C89.  And on pre-C89
>> platforms nginx is unlikely to compile without warnings anyway, as there
>> are no casts in memcpy() and memmove() calls.
>>
>> These casts were added in 1648:89a47f19b9ec without any details on why they
>> were added, and Igor does not remember details either.  The most plausible
>> explanation is that they were copied from ngx_strcmp() and were not really
>> needed even at that time.
>>
>> Prodded by Alejandro Colomar.

And of course, this patch LGTM :)

Cheers,

Alex

>>
>> diff --git a/src/core/ngx_string.h b/src/core/ngx_string.h
>> --- a/src/core/ngx_string.h
>> +++ b/src/core/ngx_string.h
>> @@ -145,7 +145,7 @@ ngx_copy(u_char *dst, u_char *src, size_
>>   
>>   
>>   /* msvc and icc7 compile memcmp() to the inline loop */
>> -#define ngx_memcmp(s1, s2, n)  memcmp((const char *) s1, (const char *) s2, n)
>> +#define ngx_memcmp(s1, s2, n)     memcmp(s1, s2, n)
>>   
>>   
>>   u_char *ngx_cpystrn(u_char *dst, u_char *src, size_t n);
> 

-- 
<http://www.alejandro-colomar.es/>

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