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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "defs.h"
  21 #include "serial.h"
  22
  23 /* Linked list of serial I/O handlers */
  24
  25 static struct serial_ops *serial_ops_list = NULL;
  26
  27 /* This is the last serial stream opened.  Used by connect command. */
  28
  29 static serial_t last_serial_opened = NULL;
  30
  31 static struct serial_ops *
  32 serial_interface_lookup (name)
  33      char *name;
  34 {
  35   struct serial_ops *ops;
  36
  37   for (ops = serial_ops_list; ops; ops = ops->next)
  38     if (strcmp (name, ops->name) == 0)
  39       return ops;
  40
  41   return NULL;
  42 }
  43
  44 void
  45 serial_add_interface(optable)
  46      struct serial_ops *optable;
  47 {
  48   optable->next = serial_ops_list;
  49   serial_ops_list = optable;
  50 }
  51
  52 /* Open up a device or a network socket, depending upon the syntax of NAME. */
  53
  54 serial_t
  55 serial_open (name)
  56      const char *name;
  57 {
  58   serial_t scb;
  59   struct serial_ops *ops;
  60
  61   for (scb = scb_base; scb; scb = scb->next)
  62     if (scb->name && strcmp (scb->name, name) == 0)
  63       {
  64         scb->refcnt++;
  65         return scb;
  66       }
  67
  68   if (strcmp (name, "pc") == 0)
  69     ops = serial_interface_lookup ("pc");
  70   else if (strchr (name, ':'))
  71     ops = serial_interface_lookup ("tcp");
  72   else
  73     ops = serial_interface_lookup ("hardwire");
  74
  75   if (!ops)
  76     return NULL;
  77
  78   scb = (serial_t)xmalloc (sizeof (struct _serial_t));
  79
  80   scb->ops = ops;
  81
  82   scb->bufcnt = 0;
  83   scb->bufp = scb->buf;
  84
  85   if (scb->ops->open(scb, name))
  86     {
  87       free (scb);
  88       return NULL;
  89     }
  90
  91   scb->name = strsave (name);
  92   scb->next = scb_base;
  93   scb->refcnt = 1;
  94   scb_base = scb;
  95
  96   last_serial_opened = scb;
  97
  98   return scb;
  99 }
 100
 101 serial_t
 102 serial_fdopen (fd)
 103      const int fd;
 104 {
 105   serial_t scb;
 106   struct serial_ops *ops;
 107
 108   for (scb = scb_base; scb; scb = scb->next)
 109     if (scb->fd == fd)
 110       {
 111         scb->refcnt++;
 112         return scb;
 113       }
 114
 115   ops = serial_interface_lookup ("hardwire");
 116
 117   if (!ops)
 118     return NULL;
 119
 120   scb = (serial_t)xmalloc (sizeof (struct _serial_t));
 121
 122   scb->ops = ops;
 123
 124   scb->bufcnt = 0;
 125   scb->bufp = scb->buf;
 126
 127   scb->fd = fd;
 128
 129   scb->name = NULL;
 130   scb->next = scb_base;
 131   scb->refcnt = 1;
 132   scb_base = scb;
 133
 134   last_serial_opened = scb;
 135
 136   return scb;
 137 }
 138
 139 void
 140 serial_close(scb)
 141      serial_t scb;
 142 {
 143   serial_t tmp_scb;
 144
 145   last_serial_opened = NULL;
 146
 147 /* This is bogus.  It's not our fault if you pass us a bad scb...!  Rob, you
 148    should fix your code instead.  */
 149
 150   if (!scb)
 151     return;
 152
 153   scb->refcnt--;
 154   if (scb->refcnt > 0)
 155     return;
 156
 157   scb->ops->close (scb);
 158
 159   if (scb->name)
 160     free (scb->name);
 161
 162   if (scb_base == scb)
 163     scb_base = scb_base->next;
 164   else
 165     for (tmp_scb = scb_base; tmp_scb; tmp_scb = tmp_scb->next)
 166       {
 167         if (tmp_scb->next != scb)
 168           continue;
 169
 170         tmp_scb->next = tmp_scb->next->next;
 171         break;
 172       }
 173
 174   free(scb);
 175 }
 176
 177 #if 0
 178 /*
 179 The connect command is #if 0 because I hadn't thought of an elegant
 180 way to wait for I/O on two serial_t's simultaneously.  Two solutions
 181 came to mind:
 182
 183         1) Fork, and have have one fork handle the to user direction,
 184            and have the other hand the to target direction.  This
 185            obviously won't cut it for MSDOS.
 186
 187         2) Use something like select.  This assumes that stdin and
 188            the target side can both be waited on via the same
 189            mechanism.  This may not be true for DOS, if GDB is
 190            talking to the target via a TCP socket.
 191 -grossman, 8 Jun 93
 192 */
 193
 194 /* Connect the user directly to the remote system.  This command acts just like
 195    the 'cu' or 'tip' command.  Use <CR>~. or <CR>~^D to break out.  */
 196
 197 static serial_t tty_desc;               /* Controlling terminal */
 198
 199 static void
 200 cleanup_tty(ttystate)
 201      serial_ttystate ttystate;
 202 {
 203   printf_unfiltered ("\r\n[Exiting connect mode]\r\n");
 204   SERIAL_SET_TTY_STATE (tty_desc, ttystate);
 205   free (ttystate);
 206   SERIAL_CLOSE (tty_desc);
 207 }
 208
 209 static void
 210 connect_command (args, fromtty)
 211      char       *args;
 212      int        fromtty;
 213 {
 214   int c;
 215   char cur_esc = 0;
 216   serial_ttystate ttystate;
 217   serial_t port_desc;           /* TTY port */
 218
 219   dont_repeat();
 220
 221   if (args)
 222     fprintf_unfiltered(gdb_stderr, "This command takes no args.  They have been ignored.\n");
 223
 224   printf_unfiltered("[Entering connect mode.  Use ~. or ~^D to escape]\n");
 225
 226   tty_desc = SERIAL_FDOPEN (0);
 227   port_desc = last_serial_opened;
 228
 229   ttystate = SERIAL_GET_TTY_STATE (tty_desc);
 230
 231   SERIAL_RAW (tty_desc);
 232   SERIAL_RAW (port_desc);
 233
 234   make_cleanup (cleanup_tty, ttystate);
 235
 236   while (1)
 237     {
 238       int mask;
 239
 240       mask = SERIAL_WAIT_2 (tty_desc, port_desc, -1);
 241
 242       if (mask & 2)
 243         {                       /* tty input */
 244           char cx;
 245
 246           while (1)
 247             {
 248               c = SERIAL_READCHAR(tty_desc, 0);
 249
 250               if (c == SERIAL_TIMEOUT)
 251                   break;
 252
 253               if (c < 0)
 254                 perror_with_name("connect");
 255
 256               cx = c;
 257               SERIAL_WRITE(port_desc, &cx, 1);
 258
 259               switch (cur_esc)
 260                 {
 261                 case 0:
 262                   if (c == '\r')
 263                     cur_esc = c;
 264                   break;
 265                 case '\r':
 266                   if (c == '~')
 267                     cur_esc = c;
 268                   else
 269                     cur_esc = 0;
 270                   break;
 271                 case '~':
 272                   if (c == '.' || c == '\004')
 273                     return;
 274                   else
 275                     cur_esc = 0;
 276                 }
 277             }
 278         }
 279
 280       if (mask & 1)
 281         {                       /* Port input */
 282           char cx;
 283
 284           while (1)
 285             {
 286               c = SERIAL_READCHAR(port_desc, 0);
 287
 288               if (c == SERIAL_TIMEOUT)
 289                   break;
 290
 291               if (c < 0)
 292                 perror_with_name("connect");
 293
 294               cx = c;
 295
 296               SERIAL_WRITE(tty_desc, &cx, 1);
 297             }
 298         }
 299     }
 300 }
 301 #endif /* 0 */
 302
 303 void
 304 _initialize_serial ()
 305 {
 306 #if 0
 307   add_com ("connect", class_obscure, connect_command,
 308            "Connect the terminal directly up to the command monitor.\n\
 309 Use <CR>~. or <CR>~^D to break out.");
 310 #endif /* 0 */
 311 }