On Tue, 2017-03-07 at 13:42 +0100, Georg Chini wrote: > On 04.02.2017 13:19, Tanu Kaskinen wrote: > > Clang didn't like the variable length array: > > > > pulsecore/iochannel.c:358:17: error: fields must have a constant size: > > 'variable length array in structure' extension will never be supported > > uint8_t data[CMSG_SPACE(sizeof(int) * nfd)]; > > ^ > > > > Commit 451d1d6762 introduced the variable length array in order to have > > the correct value in msg_controllen. This patch reverts that commit and > > uses a different way to achieve the same goal. > > > > BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=99458 > > --- > > src/pulsecore/iochannel.c | 10 ++++++++-- > > 1 file changed, 8 insertions(+), 2 deletions(-) > > > > diff --git a/src/pulsecore/iochannel.c b/src/pulsecore/iochannel.c > > index 8ace297ff..897337522 100644 > > --- a/src/pulsecore/iochannel.c > > +++ b/src/pulsecore/iochannel.c > > @@ -355,7 +355,7 @@ ssize_t pa_iochannel_write_with_fds(pa_iochannel*io, const void*data, size_t l, > > struct iovec iov; > > union { > > struct cmsghdr hdr; > > - uint8_t data[CMSG_SPACE(sizeof(int) * nfd)]; > > + uint8_t data[CMSG_SPACE(sizeof(int) * MAX_ANCIL_DATA_FDS)]; > > } cmsg; > > > > pa_assert(io); > > @@ -382,7 +382,13 @@ ssize_t pa_iochannel_write_with_fds(pa_iochannel*io, const void*data, size_t l, > > mh.msg_iov = &iov; > > mh.msg_iovlen = 1; > > mh.msg_control = &cmsg; > > - mh.msg_controllen = sizeof(cmsg); > > + > > + /* If we followed the example on the cmsg man page, we'd use > > + * sizeof(cmsg.data) here, but if nfd < MAX_ANCIL_DATA_FDS, then the data > > + * buffer is larger than needed, and the kernel doesn't like it if we set > > + * msg_controllen to a larger than necessary value. The commit message for > > + * commit 451d1d6762 contains a longer explanation. */ > > + mh.msg_controllen = CMSG_SPACE(sizeof(int) * nfd); > > > > if ((r = sendmsg(io->ofd, &mh, MSG_NOSIGNAL)) >= 0) { > > io->writable = io->hungup = false; > > Looks OK to me. Someone is complaining on IRC about that bug, so maybe > you should push it soon. Thanks for the review, I applied the patch now. That someone is probably the Travis bot. Travis does a test build every time something is pushed, and that started to fail when a clang build was added to the Travis configuration. -- Tanu https://www.patreon.com/tanuk
