support remote connections over unix domain sockets

["Ryan Brown" <ribrdb@google.com>]

This patch modifies net_open in ser-tcp.c to connect to a remote
target named unix:/foo/bar via the unix domain socket /foo/bar.


2006-04-25  Ryan Brown  <ribrdb@google.com >

    * ser-tcp.c (net_open): Add support for unix domain sockets.



Index: gdb/ser-tcp.c
==============================
=====================================
RCS file: /cvs/src/src/gdb/ser- tcp.c,v
retrieving revision 1.26
diff -c -p -r1.26 ser-tcp.c
*** gdb/ser-tcp.c    10 Feb 2006 22:01:43 -0000    1.26
--- gdb/ser-tcp.c    25 Apr 2006 23:28:42 -0000
***************
*** 47,52 ****
--- 47,53 ----
  #include <netdb.h>
  #include <sys/socket.h>
  #include <netinet/tcp.h>
+ #include <sys/un.h>
  #endif

  #include <signal.h>
*************** net_open (struct serial *scb, const char
*** 70,78 ****
  {
    char *port_str, hostname[100];
    int n, port, tmp;
!   int use_udp;
    struct hostent *hostent;
-   struct sockaddr_in sockaddr;
  #ifdef USE_WIN32API
    u_long ioarg;
  #else
--- 71,78 ----
  {
    char *port_str, hostname[100];
    int n, port, tmp;
!   int use_udp, use_unix;
    struct hostent *hostent;
  #ifdef USE_WIN32API
    u_long ioarg;
  #else
 *************** net_open (struct serial *scb, const char
*** 80,134 ****
  #endif

    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 (_("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 */
!   hostname[tmp] = '\000';    /* Tie off host name */
!   port = atoi (port_str + 1);

!   /* default hostname is localhost */
!   if (!hostname[0])
!     strcpy (hostname, "localhost");

!   hostent = gethostbyname (hostname);
!   if (!hostent)
!     {
!       fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
!       errno = ENOENT;
!       return -1;
      }
-
-   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;

-   sockaddr.sin_family = PF_INET;
-   sockaddr.sin_port = htons (port);
-   memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
-       sizeof (struct in_addr));
-
    /* set socket nonblocking */
    ioarg = 1;
    ioctl (scb->fd, FIONBIO, &ioarg);

    /* Use Non-blocking connect.  connect() will return 0 if connected
already. */
!   n = connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof (sockaddr));

    if (n < 0
  #ifdef USE_WIN32API
--- 80,162 ----
  #endif

    use_udp = 0;
+   use_unix = 0;
    if (strncmp (name, "udp:", 4) == 0)
      {
        use_udp = 1;
         name = name + 4;
      }
+   else if (strncmp (name, "unix:", 5) == 0)
+     {
+       use_unix = 1;
+       name = name + 5;
+     }
    else if (strncmp (name, "tcp:", 4) == 0)
      name = name + 4;

!   if (use_unix)
!     {
!       scb->fd = socket (AF_UNIX, SOCK_STREAM, 0);
!       port = 0;
!       hostent = 0;
!     }
!   else
!     {
!       port_str = strchr (name, ':');

!       if (!port_str)
!     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 */
!       hostname[tmp] = '\000';    /* Tie off host name */
!       port = atoi (port_str + 1);
!
!       /* default hostname is localhost */
!       if (!hostname[0])
!     strcpy (hostname, "localhost");

!       hostent = gethostbyname (hostname);
!       if (!hostent)
!     {
!       fprintf_unfiltered (gdb_stderr, "%s: unknown host\n", hostname);
!       errno = ENOENT;
!       return -1;
!     }

!       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;

    /* set socket nonblocking */
    ioarg = 1;
    ioctl (scb->fd, FIONBIO, &ioarg);

    /* Use Non-blocking connect.  connect() will return 0 if connected
already. */
!   if (use_unix)
!     {
!       struct sockaddr_un sockaddr;
!       memset(&sockaddr, 0, sizeof(sockaddr));
!       strncpy(sockaddr.sun_path, name, sizeof (sockaddr.sun_path));
!       sockaddr.sun_path[sizeof (sockaddr.sun_path ) - 1] = 0;
!       sockaddr.sun_family = AF_UNIX;
!
!       n = connect(scb->fd, (struct sockaddr *)&sockaddr, SUN_LEN(&sockaddr));
!     }
!   else
!     {
!       struct sockaddr_in sockaddr;
!       sockaddr.sin_family = PF_INET;
!       sockaddr.sin_port = htons (port);
!       memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
!           sizeof (struct in_addr));
!
!       n = connect (scb->fd, (struct sockaddr *) &sockaddr, sizeof
(sockaddr));
!     }

    if (n < 0
  #ifdef USE_WIN32API