Re: Use of strtok() in dpdk code

[fengchengwen <fengchengwen@huawei.com>]

On 2024/10/22 9:08, Stephen Hemminger wrote:
> On Mon, 21 Oct 2024 21:30:02 +0300
> Isaac Boukris <iboukris@gmail.com> wrote:
> 
>> Hello,
>>
>> I was debugging a crash resulting from strtok() returning NULL
>> unexpectedly (string still had tokens and delimiters), and the only
>> explanation I could come up with was that strtok is thread-unsafe and
>> another thread could have been calling it at the same time, and so I
>> changed it to use strtok_r().
>>
>> That said, the only other possible use of strtok() that I could find
>> was in the dpdk code (telemetry), which brings me to my question,
>> should we consider changing all occurrences to strtok_r() or am I
>> missing something? there seem to be quite some in non-initialization
>> code.
>>
>> Thanks!
> 
> 
> Most of the uses are in tests and other single threaded code.
> In general, simpler just to use strtok_r everywhere and not worry about it.
> Similar to not using sprintf() and instead using snprintf().

I'm afraid I can't agree.

DPDK is just a SDK, it's not an application (although DPDK provided simple examples).
Many code will developped based on DPDK, we can't predict how it was implemented.
So there maybe a DPDK thread and a application thread both invoke strtok().

From this point of view, I hope that DPDK solves some of the reentrant problems of
such C functions (e.g. strtok()\strerror()).

Actually, we've try to solve before, but unfortunately it wasn't merged.
1\ strtok():   https://inbox.dpdk.org/dev/20231114110006.91148-1-haijie1@huawei.com/T/#u
2\ strerror(): https://inbox.dpdk.org/dev/20231114123552.398072-1-huangdengdui@huawei.com/T/#u

> 
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