gdb/serial.c

   1 /* Generic serial interface routines
   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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #include "defs.h"
  21 #include "serial.h"
  22 #include "gdb_string.h"
  23
  24 /* Linked list of serial I/O handlers */
  25
  26 static struct serial_ops *serial_ops_list = NULL;
  27
  28 /* This is the last serial stream opened.  Used by connect command. */
  29
  30 static serial_t last_serial_opened = NULL;
  31
  32 /* Pointer to list of scb's. */
  33
  34 static serial_t scb_base;
  35
  36 static struct serial_ops *
  37 serial_interface_lookup (name)
  38      char *name;
  39 {
  40   struct serial_ops *ops;
  41
  42   for (ops = serial_ops_list; ops; ops = ops->next)
  43     if (strcmp (name, ops->name) == 0)
  44       return ops;
  45
  46   return NULL;
  47 }
  48
  49 void
  50 serial_add_interface(optable)
  51      struct serial_ops *optable;
  52 {
  53   optable->next = serial_ops_list;
  54   serial_ops_list = optable;
  55 }
  56
  57 /* Open up a device or a network socket, depending upon the syntax of NAME. */
  58
  59 serial_t
  60 serial_open (name)
  61      const char *name;
  62 {
  63   serial_t scb;
  64   struct serial_ops *ops;
  65
  66   for (scb = scb_base; scb; scb = scb->next)
  67     if (scb->name && strcmp (scb->name, name) == 0)
  68       {
  69         scb->refcnt++;
  70         return scb;
  71       }
  72
  73   if (strcmp (name, "pc") == 0)
  74     ops = serial_interface_lookup ("pc");
  75   else if (strchr (name, ':'))
  76     ops = serial_interface_lookup ("tcp");
  77   else
  78     ops = serial_interface_lookup ("hardwire");
  79
  80   if (!ops)
  81     return NULL;
  82
  83   scb = (serial_t)xmalloc (sizeof (struct _serial_t));
  84
  85   scb->ops = ops;
  86
  87   scb->bufcnt = 0;
  88   scb->bufp = scb->buf;
  89
  90   if (scb->ops->open(scb, name))
  91     {
  92       free (scb);
  93       return NULL;
  94     }
  95
  96   scb->name = strsave (name);
  97   scb->next = scb_base;
  98   scb->refcnt = 1;
  99   scb_base = scb;
 100
 101   last_serial_opened = scb;
 102
 103   return scb;
 104 }
 105
 106 serial_t
 107 serial_fdopen (fd)
 108      const int fd;
 109 {
 110   serial_t scb;
 111   struct serial_ops *ops;
 112
 113   for (scb = scb_base; scb; scb = scb->next)
 114     if (scb->fd == fd)
 115       {
 116         scb->refcnt++;
 117         return scb;
 118       }
 119
 120   ops = serial_interface_lookup ("hardwire");
 121
 122   if (!ops)
 123     return NULL;
 124
 125   scb = (serial_t)xmalloc (sizeof (struct _serial_t));
 126
 127   scb->ops = ops;
 128
 129   scb->bufcnt = 0;
 130   scb->bufp = scb->buf;
 131
 132   scb->fd = fd;
 133
 134   scb->name = NULL;
 135   scb->next = scb_base;
 136   scb->refcnt = 1;
 137   scb_base = scb;
 138
 139   last_serial_opened = scb;
 140
 141   return scb;
 142 }
 143
 144 void
 145 serial_close(scb, really_close)
 146      serial_t scb;
 147      int really_close;
 148 {
 149   serial_t tmp_scb;
 150
 151   last_serial_opened = NULL;
 152
 153 /* This is bogus.  It's not our fault if you pass us a bad scb...!  Rob, you
 154    should fix your code instead.  */
 155
 156   if (!scb)
 157     return;
 158
 159   scb->refcnt--;
 160   if (scb->refcnt > 0)
 161     return;
 162
 163   if (really_close)
 164     scb->ops->close (scb);
 165
 166   if (scb->name)
 167     free (scb->name);
 168
 169   if (scb_base == scb)
 170     scb_base = scb_base->next;
 171   else
 172     for (tmp_scb = scb_base; tmp_scb; tmp_scb = tmp_scb->next)
 173       {
 174         if (tmp_scb->next != scb)
 175           continue;
 176
 177         tmp_scb->next = tmp_scb->next->next;
 178         break;
 179       }
 180
 181   free(scb);
 182 }
 183
 184 #if 0
 185 /*
 186 The connect command is #if 0 because I hadn't thought of an elegant
 187 way to wait for I/O on two serial_t's simultaneously.  Two solutions
 188 came to mind:
 189
 190         1) Fork, and have have one fork handle the to user direction,
 191            and have the other hand the to target direction.  This
 192            obviously won't cut it for MSDOS.
 193
 194         2) Use something like select.  This assumes that stdin and
 195            the target side can both be waited on via the same
 196            mechanism.  This may not be true for DOS, if GDB is
 197            talking to the target via a TCP socket.
 198 -grossman, 8 Jun 93
 199 */
 200
 201 /* Connect the user directly to the remote system.  This command acts just like
 202    the 'cu' or 'tip' command.  Use <CR>~. or <CR>~^D to break out.  */
 203
 204 static serial_t tty_desc;               /* Controlling terminal */
 205
 206 static void
 207 cleanup_tty(ttystate)
 208      serial_ttystate ttystate;
 209 {
 210   printf_unfiltered ("\r\n[Exiting connect mode]\r\n");
 211   SERIAL_SET_TTY_STATE (tty_desc, ttystate);
 212   free (ttystate);
 213   SERIAL_CLOSE (tty_desc);
 214 }
 215
 216 static void
 217 connect_command (args, fromtty)
 218      char       *args;
 219      int        fromtty;
 220 {
 221   int c;
 222   char cur_esc = 0;
 223   serial_ttystate ttystate;
 224   serial_t port_desc;           /* TTY port */
 225
 226   dont_repeat();
 227
 228   if (args)
 229     fprintf_unfiltered(gdb_stderr, "This command takes no args.  They have been ignored.\n");
 230
 231   printf_unfiltered("[Entering connect mode.  Use ~. or ~^D to escape]\n");
 232
 233   tty_desc = SERIAL_FDOPEN (0);
 234   port_desc = last_serial_opened;
 235
 236   ttystate = SERIAL_GET_TTY_STATE (tty_desc);
 237
 238   SERIAL_RAW (tty_desc);
 239   SERIAL_RAW (port_desc);
 240
 241   make_cleanup (cleanup_tty, ttystate);
 242
 243   while (1)
 244     {
 245       int mask;
 246
 247       mask = SERIAL_WAIT_2 (tty_desc, port_desc, -1);
 248
 249       if (mask & 2)
 250         {                       /* tty input */
 251           char cx;
 252
 253           while (1)
 254             {
 255               c = SERIAL_READCHAR(tty_desc, 0);
 256
 257               if (c == SERIAL_TIMEOUT)
 258                   break;
 259
 260               if (c < 0)
 261                 perror_with_name("connect");
 262
 263               cx = c;
 264               SERIAL_WRITE(port_desc, &cx, 1);
 265
 266               switch (cur_esc)
 267                 {
 268                 case 0:
 269                   if (c == '\r')
 270                     cur_esc = c;
 271                   break;
 272                 case '\r':
 273                   if (c == '~')
 274                     cur_esc = c;
 275                   else
 276                     cur_esc = 0;
 277                   break;
 278                 case '~':
 279                   if (c == '.' || c == '\004')
 280                     return;
 281                   else
 282                     cur_esc = 0;
 283                 }
 284             }
 285         }
 286
 287       if (mask & 1)
 288         {                       /* Port input */
 289           char cx;
 290
 291           while (1)
 292             {
 293               c = SERIAL_READCHAR(port_desc, 0);
 294
 295               if (c == SERIAL_TIMEOUT)
 296                   break;
 297
 298               if (c < 0)
 299                 perror_with_name("connect");
 300
 301               cx = c;
 302
 303               SERIAL_WRITE(tty_desc, &cx, 1);
 304             }
 305         }
 306     }
 307 }
 308 #endif /* 0 */
 309
 310 void
 311 _initialize_serial ()
 312 {
 313 #if 0
 314   add_com ("connect", class_obscure, connect_command,
 315            "Connect the terminal directly up to the command monitor.\n\
 316 Use <CR>~. or <CR>~^D to break out.");
 317 #endif /* 0 */
 318 }