[PATCH] erofs-utils: use cmpsgn(x, y) for standardized large value comparsion

[Li Guifu]

Hi Gao Xiang,

It runs ok, but could you resend it to adjust line algin ?

 >> -#define sgn(x) ({		\
 >> +#define cmpsgn(x, y) ({		\
 >>   	typeof(x) _x = (x);	\
 >> -(_x > 0) - (_x < 0); })
 >> +	typeof(y) _y = (y);	\
 >> +(_x > _y) - (_x < _y); }) ----> here


> On Mon, Oct 14, 2019 at 07:30:48PM +0800, Gao Xiang wrote:
>> Previously, roundup(bb->buffers.off % EROFS_BLKSIZ, alignsize)
>> + incr + extrasize is a unsigned 64bit value and sgn(x) didn't
>> work properly. Fix it.
> 
> Update commit message:
> 
> erofs-utils: use cmpsgn(x, y) for standardized large value comparsion
>      
> Previously, roundup(bb->buffers.off % EROFS_BLKSIZ, alignsize)
> + incr + extrasize is an unsigned 64bit value and sgn(x) didn't
> work properly. Fix it.
>      
> Fixes: b0ca535297b6 ("erofs-utils: support 64-bit internal buffer cache")
> 
> Guifu, do you have time reviewing and testing those patches?
> I'd like to release erofs-utils 1.0 for upstreaming AOSP these days...
> 
> Thanks,
> Gao Xiang
> 
>>
>> Signed-off-by: Gao Xiang <hsiangkao at aol.com>
>> ---
>>   include/erofs/defs.h | 5 +++--
>>   lib/cache.c          | 6 +++---
>>   2 files changed, 6 insertions(+), 5 deletions(-)
>>
>> diff --git a/include/erofs/defs.h b/include/erofs/defs.h
>> index 15db4e3..db51350 100644
>> --- a/include/erofs/defs.h
>> +++ b/include/erofs/defs.h
>> @@ -136,9 +136,10 @@ typedef int64_t         s64;
>>   	type __max2 = (y);			\
>>   	__max1 > __max2 ? __max1: __max2; })
>>   
>> -#define sgn(x) ({		\
>> +#define cmpsgn(x, y) ({		\
>>   	typeof(x) _x = (x);	\
>> -(_x > 0) - (_x < 0); })
>> +	typeof(y) _y = (y);	\
>> +(_x > _y) - (_x < _y); })
>>   
>>   #define ARRAY_SIZE(arr)	(sizeof(arr) / sizeof((arr)[0]))
>>   
>> diff --git a/lib/cache.c b/lib/cache.c
>> index 41d2d5d..e61b201 100644
>> --- a/lib/cache.c
>> +++ b/lib/cache.c
>> @@ -80,9 +80,9 @@ static int __erofs_battach(struct erofs_buffer_block *bb,
>>   			   bool dryrun)
>>   {
>>   	const erofs_off_t alignedoffset = roundup(bb->buffers.off, alignsize);
>> -	const int oob = sgn(roundup(bb->buffers.off % EROFS_BLKSIZ,
>> -				    alignsize) + incr + extrasize -
>> -			    EROFS_BLKSIZ);
>> +	const int oob = cmpsgn(roundup(bb->buffers.off % EROFS_BLKSIZ,
>> +				       alignsize) + incr + extrasize,
>> +			       EROFS_BLKSIZ);
>>   	bool tailupdate = false;
>>   	erofs_blk_t blkaddr;
>>   
>> -- 
>> 2.17.1
>>