[Ffmpeg-devel] poll() emulation for ffserver

[matthieu castet]

matthieu castet wrote:
> Hi,
> 
> Fran?ois Revol wrote:
> 
>> +
>> +    FD_ZERO(&read_set);
>> +    FD_ZERO(&write_set);
>> +    FD_ZERO(&exception_set);
>> +
>> +    n = -1;
>> +    for(i = 0; i < numfds; i++) {
>> +        if (fds[i].fd < 0)
>> +            continue;
>> +
>> +        if (fds[i].events & POLLIN)  FD_SET(fds[i].fd, &read_set);
>> +        if (fds[i].events & POLLOUT) FD_SET(fds[i].fd, &write_set);
>> +        if (fds[i].events & POLLERR) FD_SET(fds[i].fd, &exception_set);
> You you check if numfds >= FD_SETSIZE :
in fact it is fds[i].fd >= FD_SETSIZE
> 
> man select
> [...]
> An fd_set is a fixed size buffer.  Executing FD_CLR() or FD_SET()  with
> a value of fd that is negative or is equal to or larger than FD_SETSIZE
> will result in undefined behavior. Moreover, POSIX requires fd to be  a
> valid file descriptor.
> 
>