[RFA] Remote UDP support

Daniel Jacobowitz
2002-05-08T23:26:39Z

A patch for this feature was supported a year or so ago, but never went in.
I had a need for this a couple of days ago, so I did it over from scratch;
it's much easier now than it was at the time. The name of ser-tcp.c is a
bit wrong after this patch; I can either rename the file to ser-net.c or
just update some comments to match. Got a preference? Otherwise OK?

--
Daniel Jacobowitz Carnegie Mellon University
MontaVista Software Debian GNU/Linux Developer

2002-05-08 Daniel Jacobowitz <drow@mvista.com>

* ser-tcp.c: Include <netinet/udp.h>. Rename tcp_open
and tcp_close to net_open and net_close.
(net_open): Accept "udp:" and "tcp:" specifications. Connect
using UDP if requested. Don't try to disable Nagle on UDP
sockets.

Index: ser-tcp.c
===================================================================
RCS file: /cvs/src/src/gdb/ser-tcp.c,v
retrieving revision 1.10
diff -u -p -r1.10 ser-tcp.c
--- ser-tcp.c 18 Dec 2001 18:54:18 -0000 1.10
+++ ser-tcp.c 8 May 2002 23:21:58 -0000
@@ -38,12 +38,13 @@
#include <netdb.h>
#include <sys/socket.h>
#include <netinet/tcp.h>
+#include <netinet/udp.h>

#include <signal.h>
#include "gdb_string.h"

-static int tcp_open (struct serial *scb, const char *name);
-static void tcp_close (struct serial *scb);
+static int net_open (struct serial *scb, const char *name);
+static void net_close (struct serial *scb);
extern int (*ui_loop_hook) (int);
void _initialize_ser_tcp (void);

@@ -55,17 +56,27 @@ void _initialize_ser_tcp (void);
/* Open a tcp socket */

static int
-tcp_open (struct serial *scb, const char *name)
+net_open (struct serial *scb, const char *name)
{
char *port_str, hostname[100];
int n, port, tmp;
+ int use_udp;
struct hostent *hostent;
struct sockaddr_in sockaddr;

+ use_udp = 0;
+ if (strncmp (name, "udp:", 4) == 0)
+ {
+ use_udp = 1;
+ name = name + 4;
+ }
+ else if (strncmp (name, "tcp:", 4) == 0)
+ name = name + 4;
+
port_str = strchr (name, ':');

if (!port_str)
- error ("tcp_open: No colon in host name!"); /* Shouldn't ever happen */
+ error ("net_open: No colon in host name!"); /* Shouldn't ever happen */

tmp = min (port_str - name, (int) sizeof hostname - 1);
strncpy (hostname, name, tmp); /* Don't want colon */
@@ -84,7 +95,11 @@ tcp_open (struct serial *scb, const char
return -1;
}

- scb->fd = socket (PF_INET, SOCK_STREAM, 0);
+ if (use_udp)
+ scb->fd = socket (PF_INET, SOCK_DGRAM, 0);
+ else
+ scb->fd = socket (PF_INET, SOCK_STREAM, 0);
+
if (scb->fd < 0)
return -1;

@@ -102,7 +117,7 @@ tcp_open (struct serial *scb, const char

if (n < 0 && errno != EINPROGRESS)
{
- tcp_close (scb);
+ net_close (scb);
return -1;
}

@@ -124,7 +139,7 @@ tcp_open (struct serial *scb, const char
if (ui_loop_hook (0))
{
errno = EINTR;
- tcp_close (scb);
+ net_close (scb);
return -1;
}
}
@@ -142,7 +157,7 @@ tcp_open (struct serial *scb, const char
{
if (polls > TIMEOUT * POLL_INTERVAL)
errno = ETIMEDOUT;
- tcp_close (scb);
+ net_close (scb);
return -1;
}
}
@@ -156,20 +171,23 @@ tcp_open (struct serial *scb, const char
{
if (err)
errno = err;
- tcp_close (scb);
+ net_close (scb);
return -1;
}
}
-
+
/* turn off nonblocking */
tmp = 0;
ioctl (scb->fd, FIONBIO, &tmp);

- /* Disable Nagle algorithm. Needed in some cases. */
- tmp = 1;
- setsockopt (scb->fd, IPPROTO_TCP, TCP_NODELAY,
- (char *)&tmp, sizeof (tmp));
-
+ if (use_udp == 0)
+ {
+ /* Disable Nagle algorithm. Needed in some cases. */
+ tmp = 1;
+ setsockopt (scb->fd, IPPROTO_TCP, TCP_NODELAY,
+ (char *)&tmp, sizeof (tmp));
+ }
+
/* If we don't do this, then GDB simply exits
when the remote side dies. */
signal (SIGPIPE, SIG_IGN);
@@ -178,7 +196,7 @@ tcp_open (struct serial *scb, const char
}

static void
-tcp_close (struct serial *scb)
+net_close (struct serial *scb)
{
if (scb->fd < 0)
return;
@@ -194,8 +212,8 @@ _initialize_ser_tcp (void)
memset (ops, sizeof (struct serial_ops), 0);
ops->name = "tcp";
ops->next = 0;
- ops->open = tcp_open;
- ops->close = tcp_close;
+ ops->open = net_open;
+ ops->close = net_close;
ops->readchar = ser_unix_readchar;
ops->write = ser_unix_write;
ops->flush_output = ser_unix_nop_flush_output;