This reverts commit 2886c93d1bca231260ebc01d4205743ca781f3c7.
The original commit has two problems:
- It sets SO_SNDBUF to be as large as MAXLINE. But for unix domain sockets, the send buffer is bypassed. Packets go directly to the peer's receive buffer, so setting and querying SO_SNDBUF is ineffective. To ensure that the socket can accept messages of a certain size, it would be necessary to add a SO_PEERRCVBUF socket option that could query the connected peer's receive buffer size.
- It sets MAXLINE to 8 kB, which is larger than the default sockbuf size of 4 kB. That's ok for the builtin syslogd, which sets its recvbuf to 80 kB, but not ok for alternative sysloggers, like rsyslogd, which use the default size.
As a consequence, writing messages of more than 4 kB with syslog() as a
non-root user while running rsyslogd would cause the logging application
to spin indefinitely within syslog().
MFC: 2 weeks
Sponsored by: Axcient