RTEMS permits using the SO_SNDTIMEO and SO_RCVTIMEO socket options to
set a timeout for most socket I/O operations. However, in RTEMS
4.0.0, those options do not affect connect or accept. I don't know of
any way to put a timeout on those calls in RTEMS 4.0.0; can anybody
point to one.
Since it is frequently useful to have a timeout on accept, and
sometimes useful to have a timeout on connect shorter than the BSD
system default of 75 seconds, the following patch causes SO_RCVTIMEO
to affect connect and accept.
and RPC support to RTEMS. Thanks. :) Email follows:
Hello,
For Xmas, here is the Remote Debugger on RTEMS !
Here are 2 patches for the Remote Debugger on RTEMS for pc386 from Linux
host :
- one for RTEMS it self,
- one for GDB-4.17.
1/ RTEMS patch
--------------
This patch adds 2 libraries :
- a simplified SUN RPC library
- the Remote Debugger library
The configuration command is the following :
../rtems4/configure --target=i386-rtemself --enable-rtemsbsp=pc386
--enable-rdbg
The SUN RPC library is built only if networking is set.
The RDBG library is built if networking and enable-rdbg are set.
The function used to initialize the debugger is :
rtems_rdbg_initialize ();
A special function has been created to force a task to be
in a "debug" state : enterRdbg().
The use of this function is not mandatory.
2/ GDB-4.17 patch
-----------------
This patch create a new RTEMS target for GDB-4.17.
The configuration command is the following :
./configure --enable-shared --target=i386RTEMS
To connect to a target, use :
target rtems [your_site_address]
Then, attach the target using : attach 1
And... Debug ;)
You can obtain the original GDB-4.17 on
ftp://ftp.debian.org/debian/dists/stable/main/source/devel/gdb_4.17.orig.tar.gz
This has been tested from a Debian 2.0.1 linux host.
overhaul of the RTEMS system call interface. This base file system is
the "In-Memory File System" aka IMFS.
The design and implementation was done by the following people:
+ Joel Sherrill (joel@OARcorp.com)
+ Jennifer Averett (jennifer@OARcorp.com)
+ Steve "Mr Mount" Salitasc (salitasc@OARcorp.com)
+ Kerwin Wade (wade@OARcorp.com)
PROBLEMS
========
+ It is VERY likely that merging this will break the UNIX port. This
can/will be fixed.
+ There is likely some reentrancy/mutual exclusion needed.
+ Eventually, there should be a "mini-IMFS" description table to
eliminate links, symlinks, etc to save memory. All you need to
have "classic RTEMS" functionality is technically directories
and device IO. All the rest could be left out to save memory.
Here is a cosmetic patch which corrects a few spelling problems in parts
written by me.
Apparently, I must have written these under the influence of ether (:-)
1) Socket timeout field changed from `short' to `long'. This makes longer
timeouts possible. With a 1 kHz system clock the old system allowed
timeouts only up to a little over 30 seconds! This change is a
slightly cleaned-up version of the patch proposed by Ian Lance Taylor.
2) Major changes to BOOTP/DHCP reply handling. Now supports much of
RFC2132. These changes were done at the request of, and with the
assistance of, Erik Ivanenko.
If you're making changes, you might want to change the network
supplement Essentially just do a global search and replace of BOOTP
with BOOTP/DHCP.
The RTEMS i386 stub in
c/src/lib/libbsp/i386/shared/comm/i386-stub.c
doesn't take advantage of some of the newer gdb remote features which
permits shorter and fewer packets.
Here is a patch which uses the 'T' response to report the registers
which gdb generally needs, and implements the 'P' request to set only
a single register. The general effect is to avoid sending all the
register contents back and forth between gdb and the stub every time
the stub stops. This also implements the 'D' request which handles
the gdb detach command, so you can cleanly quit out of the debugger
and leave the target board running.
I just happened across the sync_io support in
c/src/exec/score/cpu/unix/cpu.c
(is this documented anywhere?). That looked more useful than the
signal driven I/O I was using before, so I tried it. I ran across a
few bugs in the way it uses select.
Select changes its fd_set arguments, so you can't use global variables
for them. You have to copy them into local variables first.
If select returns -1 with errno set to EINTR, then it has not changed
any of the fd_sets. You can't start looking at them.
When clearing a descriptor, the code has the usual select off by one
error when setting sync_io_nfds.
I don't see how this code could ever have worked correctly.
I have appended a patch for the problems I found.
