gdb/gdbserver/remote-utils.c

   1 /* Remote utility routines for the remote server for GDB.
   2    Copyright 1986, 1989, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
   3    2002
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #include "server.h"
  24 #include "terminal.h"
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <sys/ioctl.h>
  28 #include <sys/file.h>
  29 #include <netinet/in.h>
  30 #include <sys/socket.h>
  31 #include <netdb.h>
  32 #include <netinet/tcp.h>
  33 #include <sys/ioctl.h>
  34 #include <signal.h>
  35 #include <fcntl.h>
  36 #include <sys/time.h>
  37 #include <unistd.h>
  38 #include <arpa/inet.h>
  39
  40 int remote_debug = 0;
  41 struct ui_file *gdb_stdlog;
  42
  43 static int remote_desc;
  44
  45 /* Open a connection to a remote debugger.
  46    NAME is the filename used for communication.  */
  47
  48 void
  49 remote_open (char *name)
  50 {
  51   int save_fcntl_flags;
  52
  53   if (!strchr (name, ':'))
  54     {
  55       remote_desc = open (name, O_RDWR);
  56       if (remote_desc < 0)
  57         perror_with_name ("Could not open remote device");
  58
  59 #ifdef HAVE_TERMIOS
  60       {
  61         struct termios termios;
  62         tcgetattr (remote_desc, &termios);
  63
  64         termios.c_iflag = 0;
  65         termios.c_oflag = 0;
  66         termios.c_lflag = 0;
  67         termios.c_cflag &= ~(CSIZE | PARENB);
  68         termios.c_cflag |= CLOCAL | CS8;
  69         termios.c_cc[VMIN] = 1;
  70         termios.c_cc[VTIME] = 0;
  71
  72         tcsetattr (remote_desc, TCSANOW, &termios);
  73       }
  74 #endif
  75
  76 #ifdef HAVE_TERMIO
  77       {
  78         struct termio termio;
  79         ioctl (remote_desc, TCGETA, &termio);
  80
  81         termio.c_iflag = 0;
  82         termio.c_oflag = 0;
  83         termio.c_lflag = 0;
  84         termio.c_cflag &= ~(CSIZE | PARENB);
  85         termio.c_cflag |= CLOCAL | CS8;
  86         termio.c_cc[VMIN] = 1;
  87         termio.c_cc[VTIME] = 0;
  88
  89         ioctl (remote_desc, TCSETA, &termio);
  90       }
  91 #endif
  92
  93 #ifdef HAVE_SGTTY
  94       {
  95         struct sgttyb sg;
  96
  97         ioctl (remote_desc, TIOCGETP, &sg);
  98         sg.sg_flags = RAW;
  99         ioctl (remote_desc, TIOCSETP, &sg);
 100       }
 101 #endif
 102
 103       fprintf (stderr, "Remote debugging using %s\n", name);
 104     }
 105   else
 106     {
 107       char *port_str;
 108       int port;
 109       struct sockaddr_in sockaddr;
 110       int tmp;
 111       int tmp_desc;
 112
 113       port_str = strchr (name, ':');
 114
 115       port = atoi (port_str + 1);
 116
 117       tmp_desc = socket (PF_INET, SOCK_STREAM, 0);
 118       if (tmp_desc < 0)
 119         perror_with_name ("Can't open socket");
 120
 121       /* Allow rapid reuse of this port. */
 122       tmp = 1;
 123       setsockopt (tmp_desc, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp,
 124                   sizeof (tmp));
 125
 126       sockaddr.sin_family = PF_INET;
 127       sockaddr.sin_port = htons (port);
 128       sockaddr.sin_addr.s_addr = INADDR_ANY;
 129
 130       if (bind (tmp_desc, (struct sockaddr *) &sockaddr, sizeof (sockaddr))
 131           || listen (tmp_desc, 1))
 132         perror_with_name ("Can't bind address");
 133
 134       tmp = sizeof (sockaddr);
 135       remote_desc = accept (tmp_desc, (struct sockaddr *) &sockaddr, &tmp);
 136       if (remote_desc == -1)
 137         perror_with_name ("Accept failed");
 138
 139       /* Enable TCP keep alive process. */
 140       tmp = 1;
 141       setsockopt (tmp_desc, SOL_SOCKET, SO_KEEPALIVE, (char *) &tmp, sizeof (tmp));
 142
 143       /* Tell TCP not to delay small packets.  This greatly speeds up
 144          interactive response. */
 145       tmp = 1;
 146       setsockopt (remote_desc, IPPROTO_TCP, TCP_NODELAY,
 147                   (char *) &tmp, sizeof (tmp));
 148
 149       close (tmp_desc);         /* No longer need this */
 150
 151       signal (SIGPIPE, SIG_IGN);        /* If we don't do this, then gdbserver simply
 152                                            exits when the remote side dies.  */
 153
 154       /* Convert IP address to string.  */
 155       fprintf (stderr, "Remote debugging from host %s\n",
 156          inet_ntoa (sockaddr.sin_addr));
 157     }
 158
 159 #if defined(F_SETFL) && defined (FASYNC)
 160   save_fcntl_flags = fcntl (remote_desc, F_GETFL, 0);
 161   fcntl (remote_desc, F_SETFL, save_fcntl_flags | FASYNC);
 162 #if defined (F_SETOWN)
 163   fcntl (remote_desc, F_SETOWN, getpid ());
 164 #endif
 165 #endif
 166   disable_async_io ();
 167 }
 168
 169 void
 170 remote_close (void)
 171 {
 172   close (remote_desc);
 173 }
 174
 175 /* Convert hex digit A to a number.  */
 176
 177 static int
 178 fromhex (int a)
 179 {
 180   if (a >= '0' && a <= '9')
 181     return a - '0';
 182   else if (a >= 'a' && a <= 'f')
 183     return a - 'a' + 10;
 184   else
 185     error ("Reply contains invalid hex digit");
 186   return 0;
 187 }
 188
 189 int
 190 unhexify (char *bin, const char *hex, int count)
 191 {
 192   int i;
 193
 194   for (i = 0; i < count; i++)
 195     {
 196       if (hex[0] == 0 || hex[1] == 0)
 197         {
 198           /* Hex string is short, or of uneven length.
 199              Return the count that has been converted so far. */
 200           return i;
 201         }
 202       *bin++ = fromhex (hex[0]) * 16 + fromhex (hex[1]);
 203       hex += 2;
 204     }
 205   return i;
 206 }
 207
 208 static void
 209 decode_address (CORE_ADDR *addrp, const char *start, int len)
 210 {
 211   CORE_ADDR addr;
 212   char ch;
 213   int i;
 214
 215   addr = 0;
 216   for (i = 0; i < len; i++)
 217     {
 218       ch = start[i];
 219       addr = addr << 4;
 220       addr = addr | (fromhex (ch) & 0x0f);
 221     }
 222   *addrp = addr;
 223 }
 224
 225 /* Convert number NIB to a hex digit.  */
 226
 227 static int
 228 tohex (int nib)
 229 {
 230   if (nib < 10)
 231     return '0' + nib;
 232   else
 233     return 'a' + nib - 10;
 234 }
 235
 236 int
 237 hexify (char *hex, const char *bin, int count)
 238 {
 239   int i;
 240
 241   /* May use a length, or a nul-terminated string as input. */
 242   if (count == 0)
 243     count = strlen (bin);
 244
 245   for (i = 0; i < count; i++)
 246     {
 247       *hex++ = tohex ((*bin >> 4) & 0xf);
 248       *hex++ = tohex (*bin++ & 0xf);
 249     }
 250   *hex = 0;
 251   return i;
 252 }
 253
 254 /* Send a packet to the remote machine, with error checking.
 255    The data of the packet is in BUF.  Returns >= 0 on success, -1 otherwise. */
 256
 257 int
 258 putpkt (char *buf)
 259 {
 260   int i;
 261   unsigned char csum = 0;
 262   char *buf2;
 263   char buf3[1];
 264   int cnt = strlen (buf);
 265   char *p;
 266
 267   buf2 = malloc (PBUFSIZ);
 268
 269   /* Copy the packet into buffer BUF2, encapsulating it
 270      and giving it a checksum.  */
 271
 272   p = buf2;
 273   *p++ = '$';
 274
 275   for (i = 0; i < cnt; i++)
 276     {
 277       csum += buf[i];
 278       *p++ = buf[i];
 279     }
 280   *p++ = '#';
 281   *p++ = tohex ((csum >> 4) & 0xf);
 282   *p++ = tohex (csum & 0xf);
 283
 284   *p = '\0';
 285
 286   /* Send it over and over until we get a positive ack.  */
 287
 288   do
 289     {
 290       int cc;
 291
 292       if (write (remote_desc, buf2, p - buf2) != p - buf2)
 293         {
 294           perror ("putpkt(write)");
 295           return -1;
 296         }
 297
 298       if (remote_debug)
 299         printf ("putpkt (\"%s\"); [looking for ack]\n", buf2);
 300       cc = read (remote_desc, buf3, 1);
 301       if (remote_debug)
 302         printf ("[received '%c' (0x%x)]\n", buf3[0], buf3[0]);
 303       if (cc <= 0)
 304         {
 305           if (cc == 0)
 306             fprintf (stderr, "putpkt(read): Got EOF\n");
 307           else
 308             perror ("putpkt(read)");
 309
 310           free (buf2);
 311           return -1;
 312         }
 313     }
 314   while (buf3[0] != '+');
 315
 316   free (buf2);
 317   return 1;                     /* Success! */
 318 }
 319
 320 /* Come here when we get an input interrupt from the remote side.  This
 321    interrupt should only be active while we are waiting for the child to do
 322    something.  About the only thing that should come through is a ^C, which
 323    will cause us to send a SIGINT to the child.  */
 324
 325 static void
 326 input_interrupt (int unused)
 327 {
 328   fd_set readset;
 329   struct timeval immediate = { 0, 0 };
 330
 331   /* Protect against spurious interrupts.  This has been observed to
 332      be a problem under NetBSD 1.4 and 1.5.  */
 333
 334   FD_ZERO (&readset);
 335   FD_SET (remote_desc, &readset);
 336   if (select (remote_desc + 1, &readset, 0, 0, &immediate) > 0)
 337     {
 338       int cc;
 339       char c;
 340
 341       cc = read (remote_desc, &c, 1);
 342
 343       if (cc != 1 || c != '\003')
 344         {
 345           fprintf (stderr, "input_interrupt, cc = %d c = %d\n", cc, c);
 346           return;
 347         }
 348
 349       kill (signal_pid, SIGINT);
 350     }
 351 }
 352
 353 void
 354 enable_async_io (void)
 355 {
 356   signal (SIGIO, input_interrupt);
 357 }
 358
 359 void
 360 disable_async_io (void)
 361 {
 362   signal (SIGIO, SIG_IGN);
 363 }
 364
 365 /* Returns next char from remote GDB.  -1 if error.  */
 366
 367 static int
 368 readchar (void)
 369 {
 370   static char buf[BUFSIZ];
 371   static int bufcnt = 0;
 372   static char *bufp;
 373
 374   if (bufcnt-- > 0)
 375     return *bufp++ & 0x7f;
 376
 377   bufcnt = read (remote_desc, buf, sizeof (buf));
 378
 379   if (bufcnt <= 0)
 380     {
 381       if (bufcnt == 0)
 382         fprintf (stderr, "readchar: Got EOF\n");
 383       else
 384         perror ("readchar");
 385
 386       return -1;
 387     }
 388
 389   bufp = buf;
 390   bufcnt--;
 391   return *bufp++ & 0x7f;
 392 }
 393
 394 /* Read a packet from the remote machine, with error checking,
 395    and store it in BUF.  Returns length of packet, or negative if error. */
 396
 397 int
 398 getpkt (char *buf)
 399 {
 400   char *bp;
 401   unsigned char csum, c1, c2;
 402   int c;
 403
 404   while (1)
 405     {
 406       csum = 0;
 407
 408       while (1)
 409         {
 410           c = readchar ();
 411           if (c == '$')
 412             break;
 413           if (remote_debug)
 414             printf ("[getpkt: discarding char '%c']\n", c);
 415           if (c < 0)
 416             return -1;
 417         }
 418
 419       bp = buf;
 420       while (1)
 421         {
 422           c = readchar ();
 423           if (c < 0)
 424             return -1;
 425           if (c == '#')
 426             break;
 427           *bp++ = c;
 428           csum += c;
 429         }
 430       *bp = 0;
 431
 432       c1 = fromhex (readchar ());
 433       c2 = fromhex (readchar ());
 434
 435       if (csum == (c1 << 4) + c2)
 436         break;
 437
 438       fprintf (stderr, "Bad checksum, sentsum=0x%x, csum=0x%x, buf=%s\n",
 439                (c1 << 4) + c2, csum, buf);
 440       write (remote_desc, "-", 1);
 441     }
 442
 443   if (remote_debug)
 444     printf ("getpkt (\"%s\");  [sending ack] \n", buf);
 445
 446   write (remote_desc, "+", 1);
 447
 448   if (remote_debug)
 449     printf ("[sent ack]\n");
 450   return bp - buf;
 451 }
 452
 453 void
 454 write_ok (char *buf)
 455 {
 456   buf[0] = 'O';
 457   buf[1] = 'K';
 458   buf[2] = '\0';
 459 }
 460
 461 void
 462 write_enn (char *buf)
 463 {
 464   buf[0] = 'E';
 465   buf[1] = 'N';
 466   buf[2] = 'N';
 467   buf[3] = '\0';
 468 }
 469
 470 void
 471 convert_int_to_ascii (char *from, char *to, int n)
 472 {
 473   int nib;
 474   char ch;
 475   while (n--)
 476     {
 477       ch = *from++;
 478       nib = ((ch & 0xf0) >> 4) & 0x0f;
 479       *to++ = tohex (nib);
 480       nib = ch & 0x0f;
 481       *to++ = tohex (nib);
 482     }
 483   *to++ = 0;
 484 }
 485
 486
 487 void
 488 convert_ascii_to_int (char *from, char *to, int n)
 489 {
 490   int nib1, nib2;
 491   while (n--)
 492     {
 493       nib1 = fromhex (*from++);
 494       nib2 = fromhex (*from++);
 495       *to++ = (((nib1 & 0x0f) << 4) & 0xf0) | (nib2 & 0x0f);
 496     }
 497 }
 498
 499 static char *
 500 outreg (int regno, char *buf)
 501 {
 502   int regsize = register_size (regno);
 503
 504   if ((regno >> 12) != 0)
 505     *buf++ = tohex ((regno >> 12) & 0xf);
 506   if ((regno >> 8) != 0)
 507     *buf++ = tohex ((regno >> 8) & 0xf);
 508   *buf++ = tohex ((regno >> 4) & 0xf);
 509   *buf++ = tohex (regno & 0xf);
 510   *buf++ = ':';
 511   convert_int_to_ascii (register_data (regno), buf, regsize);
 512   buf += 2 * regsize;
 513   *buf++ = ';';
 514
 515   return buf;
 516 }
 517
 518 void
 519 prepare_resume_reply (char *buf, char status, unsigned char signo)
 520 {
 521   int nib, sig;
 522
 523   *buf++ = status;
 524
 525   sig = (int)target_signal_from_host (signo);
 526
 527   nib = ((sig & 0xf0) >> 4);
 528   *buf++ = tohex (nib);
 529   nib = sig & 0x0f;
 530   *buf++ = tohex (nib);
 531
 532   if (status == 'T')
 533     {
 534       const char **regp = gdbserver_expedite_regs;
 535       while (*regp)
 536         {
 537           buf = outreg (find_regno (*regp), buf);
 538           regp ++;
 539         }
 540
 541       /* If the debugger hasn't used any thread features, don't burden it with
 542          threads.  If we didn't check this, GDB 4.13 and older would choke.  */
 543       if (cont_thread != 0)
 544         {
 545           if (old_thread_from_wait != thread_from_wait)
 546             {
 547               sprintf (buf, "thread:%x;", thread_from_wait);
 548               buf += strlen (buf);
 549               old_thread_from_wait = thread_from_wait;
 550             }
 551         }
 552     }
 553   /* For W and X, we're done.  */
 554   *buf++ = 0;
 555 }
 556
 557 void
 558 decode_m_packet (char *from, CORE_ADDR *mem_addr_ptr, unsigned int *len_ptr)
 559 {
 560   int i = 0, j = 0;
 561   char ch;
 562   *mem_addr_ptr = *len_ptr = 0;
 563
 564   while ((ch = from[i++]) != ',')
 565     {
 566       *mem_addr_ptr = *mem_addr_ptr << 4;
 567       *mem_addr_ptr |= fromhex (ch) & 0x0f;
 568     }
 569
 570   for (j = 0; j < 4; j++)
 571     {
 572       if ((ch = from[i++]) == 0)
 573         break;
 574       *len_ptr = *len_ptr << 4;
 575       *len_ptr |= fromhex (ch) & 0x0f;
 576     }
 577 }
 578
 579 void
 580 decode_M_packet (char *from, CORE_ADDR *mem_addr_ptr, unsigned int *len_ptr,
 581                  char *to)
 582 {
 583   int i = 0;
 584   char ch;
 585   *mem_addr_ptr = *len_ptr = 0;
 586
 587   while ((ch = from[i++]) != ',')
 588     {
 589       *mem_addr_ptr = *mem_addr_ptr << 4;
 590       *mem_addr_ptr |= fromhex (ch) & 0x0f;
 591     }
 592
 593   while ((ch = from[i++]) != ':')
 594     {
 595       *len_ptr = *len_ptr << 4;
 596       *len_ptr |= fromhex (ch) & 0x0f;
 597     }
 598
 599   convert_ascii_to_int (&from[i++], to, *len_ptr);
 600 }
 601
 602 int
 603 look_up_one_symbol (const char *name, CORE_ADDR *addrp)
 604 {
 605   char own_buf[266], *p, *q;
 606   int len;
 607
 608   /* Send the request.  */
 609   strcpy (own_buf, "qSymbol:");
 610   hexify (own_buf + strlen ("qSymbol:"), name, strlen (name));
 611   if (putpkt (own_buf) < 0)
 612     return -1;
 613
 614   /* FIXME:  Eventually add buffer overflow checking (to getpkt?)  */
 615   len = getpkt (own_buf);
 616   if (len < 0)
 617     return -1;
 618
 619   if (strncmp (own_buf, "qSymbol:", strlen ("qSymbol:")) != 0)
 620     {
 621       /* Malformed response.  */
 622       if (remote_debug)
 623         fprintf (stderr, "Malformed response to qSymbol, ignoring.\n");
 624       return -1;
 625     }
 626
 627   p = own_buf + strlen ("qSymbol:");
 628   q = p;
 629   while (*q && *q != ':')
 630     q++;
 631
 632   /* Make sure we found a value for the symbol.  */
 633   if (p == q || *q == '\0')
 634     return 0;
 635
 636   decode_address (addrp, p, q - p);
 637   return 1;
 638 }
 639