Re: [PATCH] cangen: allow DLC > 8 in increment generation mode if -8 option is given

[Oliver Hartkopp <socketcan@hartkopp.net>]

On 03.11.20 18:01, Marc Kleine-Budde wrote:
> On 11/3/20 5:51 PM, Vincent Mailhol wrote:
>> Currently, the -8 option allows DLCs greater than 8 in mix mode only.
>>
>> Add the option to also generate such DLCs in increment
>> mode. e.g.: 'cangen -8 -Li can0'
>>
>> Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
>> ---
>>   cangen.c | 20 ++++++++++++++------
>>   1 file changed, 14 insertions(+), 6 deletions(-)
>>
>> diff --git a/cangen.c b/cangen.c
>> index 5c86f26..06a1931 100644
>> --- a/cangen.c
>> +++ b/cangen.c
>> @@ -171,7 +171,7 @@ int main(int argc, char **argv)
>>   	struct pollfd fds;
>>   
>>   	struct sockaddr_can addr;
>> -	static struct canfd_frame frame;
>> +	static struct canfd_frame frame = { 0 };

I've omitted this change as a static variable is initialized with zero 
by default.

>>   	struct can_frame *ccf = (struct can_frame *)&frame;
>>   	int nbytes;
>>   	int i;
>> @@ -386,7 +386,6 @@ int main(int argc, char **argv)
>>   
>>   	while (running) {
>>   		frame.flags = 0;
>> -		ccf->len8_dlc = 0;
>>   
>>   		if (count && (--count == 0))
>>   			running = 0;
>> @@ -428,7 +427,8 @@ int main(int argc, char **argv)
>>   						ccf->len8_dlc = frame.len;
>>   
>>   					frame.len = 8; /* for about 50% of the frames */
>> -				}
>> +				} else
>> +					ccf->len8_dlc = 0;
> 
> nitpick:
> 
> please use { } on the else side, too
> 

Added the {}'s and committed the patch on 
https://github.com/hartkopp/can-utils.

Also added some stuff to support 'fixed' raw DLC values in combination 
with the '-8' option.

Thanks,
Oliver

>>   			}
>>   		}
>>   
>> @@ -507,12 +507,20 @@ resend:
>>   		if (dlc_mode == MODE_INCREMENT) {
>>   
>>   			incdlc++;
>> +			incdlc %= CAN_MAX_RAW_DLC + 1;
>>   
>> -			if (canfd && !mix) {
>> -				incdlc &= 0xF;
>> +			if (canfd && !mix)
>>   				frame.len = can_dlc2len(incdlc);
>> +			else if (len8_dlc) {
>> +				if (incdlc > CAN_MAX_DLEN) {
>> +					frame.len = CAN_MAX_DLEN;
>> +					ccf->len8_dlc = incdlc;
>> +				} else {
>> +					frame.len = incdlc;
>> +					ccf->len8_dlc = 0;
>> +				}
>>   			} else {
>> -				incdlc %= 9;
>> +				incdlc %= CAN_MAX_DLEN + 1;
>>   				frame.len = incdlc;
>>   			}
>>   		}
>>
> 
> Marc
>