On 12.08.2012 01:24, Peter Maydell wrote: > POSIX allows sendmsg() and recvmsg() to fail EMSGSIZE if passed a zero > msg.msg_iovlen (in particular the MacOS X implementation will do this). > Handle the case where iov_send_recv() is passed a zero byte count > explicitly, to avoid accidentally depending on the OS to treat zero > msg_iovlen as a no-op. > > Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> > --- > This is what was causing 'make check' to fail on MacOS X. > The other option was to declare that a zero bytecount was illegal, I guess.
Acked-by: Michael Tokarev <m...@tls.msk.ru> Kevin, does this fix the test-iov failure you're seeing on one of the build bots? Thank you! /mjt > iov.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/iov.c b/iov.c > index b333061..60705c7 100644 > --- a/iov.c > +++ b/iov.c > @@ -146,6 +146,13 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, > unsigned iov_cnt, > { > ssize_t ret; > unsigned si, ei; /* start and end indexes */ > + if (bytes == 0) { > + /* Catch the do-nothing case early, as otherwise we will pass an > + * empty iovec to sendmsg/recvmsg(), and not all implementations > + * accept this. > + */ > + return 0; > + } > > /* Find the start position, skipping `offset' bytes: > * first, skip all full-sized vector elements, */