sockets.c: Destinct pointers for restrict parameters #602
Conversation
Avoid passing the same pointer twice for `restrict` parameters for `select`. Rather copy the object for the second argument.
| tv.tv_sec = timeout / 1000; | ||
| tv.tv_usec = (timeout % 1000) * 1000; | ||
| n = select(sock+1, &fds, NULL, &fds, &tv); | ||
| n = select(sock+1, &fds, NULL, &exceptfds, &tv); |
There was a problem hiding this comment.
…and if select() sets a bit in exceptfds where is it checked in the following code?
There was a problem hiding this comment.
Good point. I might have missed something there, but afaict nobody is checking fds currently.
There was a problem hiding this comment.
Okay. I am not familiar with the semantics of select() here, but wouldn't it be the same as passing NULL if the caller is not interested in the file descriptors anyway?
There was a problem hiding this comment.
According to the manpage, NULL is equivalent to an empty set. So this is different, as it specifies a set with one fd set.
Regarding the checking of the result of select(): I can not claim to fully understand the code, but only a single fd is set in fds (FD_SET(sock, &fds);). I guess this fd is probed afterwards, so that the result of select() is not needed.
Avoid passing the same pointer twice for
restrictparameters forselect. Rather copy the object for the second argument.