gdb/ser-tcp.c

   1 /* Serial interface for raw TCP connections on Un*x like systems
   2    Copyright 1992, 1993 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "defs.h"
  21 #include "serial.h"
  22 #include <sys/types.h>
  23 #include <sys/time.h>
  24 #include <netinet/in.h>
  25 #include <arpa/inet.h>
  26 #include <netdb.h>
  27 #include <sys/socket.h>
  28 #include <netinet/tcp.h>
  29 #include "signals.h"
  30
  31 struct tcp_ttystate
  32 {
  33   int bogus;
  34 };
  35
  36 static int tcp_open PARAMS ((serial_t scb, const char *name));
  37 static void tcp_raw PARAMS ((serial_t scb));
  38 static int wait_for PARAMS ((serial_t scb, int timeout));
  39 static int tcp_readchar PARAMS ((serial_t scb, int timeout));
  40 static int tcp_setbaudrate PARAMS ((serial_t scb, int rate));
  41 static int tcp_write PARAMS ((serial_t scb, const char *str, int len));
  42 static void tcp_restore PARAMS ((serial_t scb));
  43 static void tcp_close PARAMS ((serial_t scb));
  44 static serial_ttystate tcp_get_tty_state PARAMS ((serial_t scb));
  45 static int tcp_set_tty_state PARAMS ((serial_t scb, serial_ttystate state));
  46
  47 /* Open up a raw tcp socket */
  48
  49 static int
  50 tcp_open(scb, name)
  51      serial_t scb;
  52      const char *name;
  53 {
  54   char *port_str;
  55   int port;
  56   struct hostent *hostent;
  57   struct sockaddr_in sockaddr;
  58   int tmp;
  59   char hostname[100];
  60   struct protoent *protoent;
  61
  62   port_str = strchr (name, ':');
  63
  64   if (!port_str)
  65     error ("tcp_open: No colon in host name!"); /* Shouldn't ever happen */
  66
  67   tmp = min(port_str - name + 1, sizeof hostname);
  68   strncpy (hostname, name, tmp - 1); /* Don't want colon */
  69   port = atoi (port_str + 1);
  70
  71   hostent = gethostbyname (hostname);
  72
  73   if (!hostent)
  74     {
  75       errno = ENOENT;
  76       return -1;
  77     }
  78
  79   scb->fd = socket (PF_INET, SOCK_STREAM, 0);
  80   if (scb->fd < 0)
  81     return -1;
  82
  83   /* Allow rapid reuse of this port. */
  84   tmp = 1;
  85   setsockopt (scb->fd, SOL_SOCKET, SO_REUSEADDR, (char *)&tmp, sizeof(tmp));
  86
  87   /* Enable TCP keep alive process. */
  88   tmp = 1;
  89   setsockopt (scb->fd, SOL_SOCKET, SO_KEEPALIVE, (char *)&tmp, sizeof(tmp));
  90
  91   sockaddr.sin_family = PF_INET;
  92   sockaddr.sin_port = htons(port);
  93   memcpy (&sockaddr.sin_addr.s_addr, hostent->h_addr,
  94           sizeof (struct in_addr));
  95
  96   if (connect(scb->fd, &sockaddr, sizeof(sockaddr)))
  97     {
  98       close(scb->fd);
  99       return -1;
 100     }
 101
 102   protoent = getprotobyname ("tcp");
 103   if (!protoent)
 104     return -1;
 105
 106   tmp = 1;
 107   if (setsockopt (scb->fd, protoent->p_proto, TCP_NODELAY,
 108                   (char *)&tmp, sizeof(tmp)))
 109     return -1;
 110
 111   signal(SIGPIPE, SIG_IGN);     /* If we don't do this, then GDB simply exits
 112                                    when the remote side dies.  */
 113
 114   return 0;
 115 }
 116
 117 static serial_ttystate
 118 tcp_get_tty_state(scb)
 119      serial_t scb;
 120 {
 121   struct tcp_ttystate *state;
 122
 123   state = (struct tcp_ttystate *)xmalloc(sizeof *state);
 124
 125   return (serial_ttystate)state;
 126 }
 127
 128 static int
 129 tcp_set_tty_state(scb, ttystate)
 130      serial_t scb;
 131      serial_ttystate ttystate;
 132 {
 133   struct tcp_ttystate *state;
 134
 135   state = (struct tcp_ttystate *)ttystate;
 136
 137   return 0;
 138 }
 139
 140 static void
 141 tcp_raw(scb)
 142      serial_t scb;
 143 {
 144   return;                       /* Always in raw mode */
 145 }
 146
 147 /* Wait for input on scb, with timeout seconds.  Returns 0 on success,
 148    otherwise SERIAL_TIMEOUT or SERIAL_ERROR.
 149
 150    For termio{s}, we actually just setup VTIME if necessary, and let the
 151    timeout occur in the read() in tcp_read().
 152  */
 153
 154 static int
 155 wait_for(scb, timeout)
 156      serial_t scb;
 157      int timeout;
 158 {
 159   int numfds;
 160   struct timeval tv;
 161   fd_set readfds;
 162
 163   FD_ZERO (&readfds);
 164
 165   tv.tv_sec = timeout;
 166   tv.tv_usec = 0;
 167
 168   FD_SET(scb->fd, &readfds);
 169
 170   if (timeout >= 0)
 171     numfds = select(scb->fd+1, &readfds, 0, 0, &tv);
 172   else
 173     numfds = select(scb->fd+1, &readfds, 0, 0, 0);
 174
 175   if (numfds <= 0)
 176     if (numfds == 0)
 177       return SERIAL_TIMEOUT;
 178     else
 179       return SERIAL_ERROR;      /* Got an error from select or poll */
 180
 181   return 0;
 182 }
 183
 184 /* Read a character with user-specified timeout.  TIMEOUT is number of seconds
 185    to wait, or -1 to wait forever.  Use timeout of 0 to effect a poll.  Returns
 186    char if successful.  Returns -2 if timeout expired, EOF if line dropped
 187    dead, or -3 for any other error (see errno in that case). */
 188
 189 static int
 190 tcp_readchar(scb, timeout)
 191      serial_t scb;
 192      int timeout;
 193 {
 194   int status;
 195
 196   if (scb->bufcnt-- > 0)
 197     return *scb->bufp++;
 198
 199   status = wait_for(scb, timeout);
 200
 201   if (status < 0)
 202     return status;
 203
 204   scb->bufcnt = read(scb->fd, scb->buf, BUFSIZ);
 205
 206   if (scb->bufcnt <= 0)
 207     if (scb->bufcnt == 0)
 208       return SERIAL_TIMEOUT;    /* 0 chars means timeout [may need to
 209                                    distinguish between EOF & timeouts
 210                                    someday] */
 211     else
 212       return SERIAL_ERROR;      /* Got an error from read */
 213
 214   scb->bufcnt--;
 215   scb->bufp = scb->buf;
 216   return *scb->bufp++;
 217 }
 218
 219 static int
 220 tcp_setbaudrate(scb, rate)
 221      serial_t scb;
 222      int rate;
 223 {
 224   return 0;                     /* Never fails! */
 225 }
 226
 227 static int
 228 tcp_write(scb, str, len)
 229      serial_t scb;
 230      const char *str;
 231      int len;
 232 {
 233   int cc;
 234
 235   while (len > 0)
 236     {
 237       cc = write(scb->fd, str, len);
 238
 239       if (cc < 0)
 240         return 1;
 241       len -= cc;
 242       str += cc;
 243     }
 244   return 0;
 245 }
 246
 247 static void
 248 tcp_close(scb)
 249      serial_t scb;
 250 {
 251   if (scb->fd < 0)
 252     return;
 253
 254   close(scb->fd);
 255   scb->fd = -1;
 256 }
 257
 258 static struct serial_ops tcp_ops =
 259 {
 260   "tcp",
 261   0,
 262   tcp_open,
 263   tcp_close,
 264   tcp_readchar,
 265   tcp_write,
 266   tcp_raw,
 267   tcp_get_tty_state,
 268   tcp_set_tty_state,
 269   tcp_setbaudrate,
 270 };
 271
 272 void
 273 _initialize_ser_tcp ()
 274 {
 275   serial_add_interface (&tcp_ops);
 276 }