Mercurial > hg > octave-shane > gnulib-hg
changeset 17584:c67bafa8ca26
passfd: give nicer error for recvfd at eof
I noticed that recvfd() fails with errno set to EACCES if the
other end of the socket has closed (such as if it calls _exit());
but "Permission denied" as the strerror() message doesn't read
very well. This improves things to give the nicer message:
"Transport endpoint is not connected".
* lib/passfd.c (recvfd): Fake ENOTCONN if other end closes early.
* tests/test-passfd.c (main): Enhance test to cover this.
Signed-off-by: Eric Blake <eblake@redhat.com>
| author | Eric Blake <eblake@redhat.com> |
|---|---|
| date | Tue, 24 Dec 2013 11:16:07 -0700 |
| parents | 4c8a98f49e21 |
| children | bf17232de8ba |
| files | ChangeLog lib/passfd.c tests/test-passfd.c |
| diffstat | 3 files changed, 19 insertions(+), 3 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2013-12-24 Eric Blake <eblake@redhat.com> + + passfd: give nicer error for recvfd at eof + * lib/passfd.c (recvfd): Fake ENOTCONN if other end closes early. + * tests/test-passfd.c (main): Enhance test to cover this. + 2013-12-17 Paul Eggert <eggert@cs.ucla.edu> gettimeofday: port recent C++ fix to Emacs
--- a/lib/passfd.c +++ b/lib/passfd.c @@ -110,6 +110,7 @@ struct iovec iov; struct msghdr msg; int fd = -1; + ssize_t len; # ifdef CMSG_FIRSTHDR struct cmsghdr *cmsg; char buf[CMSG_SPACE (sizeof fd)]; @@ -142,16 +143,17 @@ memcpy (CMSG_DATA (cmsg), &fd, sizeof fd); msg.msg_controllen = cmsg->cmsg_len; - if (recvmsg (sock, &msg, flags_recvmsg) < 0) + len = recvmsg (sock, &msg, flags_recvmsg); + if (len < 0) return -1; cmsg = CMSG_FIRSTHDR (&msg); /* be paranoiac */ - if (cmsg == NULL || cmsg->cmsg_len != CMSG_LEN (sizeof fd) + if (len == 0 || cmsg == NULL || cmsg->cmsg_len != CMSG_LEN (sizeof fd) || cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) { /* fake errno: at end the file is not available */ - errno = EACCES; + errno = len ? EACCES : ENOTCONN; return -1; }
--- a/tests/test-passfd.c +++ b/tests/test-passfd.c @@ -83,6 +83,7 @@ /* father */ else { + ASSERT (close (pair[1]) == 0); fd = recvfd (pair[0], 0); if (fd == -1) { @@ -116,6 +117,13 @@ perror ("fstat"); return 80; } + + /* Check behavior when sender no longer around */ + errno = 0; + fd = recvfd (pair[0], 0); + ASSERT (fd == -1); + ASSERT (errno == ENOTCONN); + return 0; } #else