EPICS needs a synchronized time-of-day clock. This patch is the changes
needed to get NTP server information from a BOOTP server.
This patch also adds NTP server information to the network configuration
structure, too.
<valette@crf.canon.fr> to add a port of the GoAhead web server
(httpd) to the RTEMS build tree. They have successfully used
this BSP on i386/pc386 and PowerPC/mcp750.
Mark and Joel spoke with Nick Berliner <nickb@goahead.com> on
26 Oct 1999 about this port and got verbal approval to include
it in RTEMS distributions.
report from Philip A. Prindeville <philipp@zembu.com>:
I was working on a device driver for a certain ethernet chipset that
occassionally wraps in its buffer, and causes a resulting mbuf chain
with only a few dozen bytes in the first mbuf of the chain.
I wouldn't have thought this would be a problem, until I ran some
stress tests that flooded the ethernet receiver with packets and
started to get panics here:
250
251 if (m->m_pkthdr.len < sizeof(struct ip))
252 goto tooshort;
253
254 #ifdef DIAGNOSTIC
255 if (m->m_len < sizeof(struct ip))
256 panic("ipintr mbuf too short");
257 #endif
258
259 if (m->m_len < sizeof (struct ip) &&
260 (m = m_pullup(m, sizeof (struct ip))) == 0) {
261 ipstat.ips_toosmall++;
262 return;
263 }
264 ip = mtod(m, struct ip *);
and the panic was at line 256. But if I #undef'd DIAGNOSTICS,
then the m_pullup() at line 260 does the right thing and the packet
ends up being processed just fine.
So I started wondering, (a) why was the test checking for
something that apparently wasn't a fatal condition but rather
one that is subsequently recovered from a couple of lines later
and (b) why panic as a diagnostic "aid" from a recoverable
condition rather than just (say) log a message to the console?
All of this seems overly severe for no reason that is readily
apparent to me.
now prototypes the malloc family in stdlib.h. This causes conflicts
with the way the network stack overrides the definitions of malloc.
As best I (being Joel) can tell, commenting stdlib.h out keeps the
files compiling and referencing the desired malloc/free but results
in more warnings.
The old system would panic when the loopback interface was included as
part of the network initialation structures. With the printf you get an
message, but the interface is still properly initialized.
I get the following warning when compiling the latest snapshot. I had
a quick look at the source -- it certainly looks to me like this is a
real bug.
../../../../src/rtems-19990709/c/src/lib/libc/mount.c:97: warning:
`options' might be used uninitialized in this function
Also, I changed the TFTP test program and TFTP driver to reflect the
changes in the way paths are passed to the TFTP driver. The TFTP driver
now needs a proper `dotted-decimal' hostname as the second component of
the path name.
The select function is not particularly efficient when dealing with a
large number of sockets. The application has to build a big set of
bits and pass it in. RTEMS has to look through all those bits and see
what is ready. Then the application has to look through all the bits
again.
On the other hand, when using RTEMS, the select function is needed
exactly when you have a large number of sockets, because that is when
it becomes prohibitive to use a separate thread for each socket.
I think it would make more sense for RTEMS to support callback
functions which could be invoked when there is data available to read
from a socket, or when there is space available to write to a socket.
Accordingly, I implemented them.
This patch adds two new SOL_SOCKET options to setsockopt and
getsockopt: SO_SNDWAKEUP and SO_RCVWAKEUP. They take arguments of
type struct sockwakeup:
struct sockwakeup {
void (*sw_pfn) __P((struct socket *, caddr_t));
caddr_t sw_arg;
};
They are used to add or remove a function which will be called when
something happens for the socket. Getting a callback doesn't imply
that a read or write will succeed, but it does imply that it is worth
trying.
This adds functionality to RTEMS which is somewhat like interrupt
driven socket I/O on Unix.
After the patch to RTEMS, I have appended a patch to
netdemos-19990407/select/test.c to test the new functionality and
demonstrate one way it might be used. To run the new test instead of
the select test, change doSocket to call echoServer2 instead of
echoServer.
Ian Lance Taylor <ian@airs.com>:
Ian Lance Taylor wrote:
>
> In rtems-19990528, sbwait sets SB_WAIT in sb_flags. sowakeup checks
> it. Why doesn't socket_select set it?
>
> I don't know that this is a bug--I haven't tried to create a test
> case. However, it certainly looks odd.
>
> Ian
Yes, there's a bug there. Sorry about that.
It was introduced when I did some cleanup on the sleep/wakeup handling
in rtems_glue.c.
allows one to trace the enqueueing and dequeueing of messages. This
can be used to insure that packets are getting to the boundary between
the network stack and the device driver.
Joel Sherrill