gdb/symm-nat.c

   1 /* Sequent Symmetry host interface, for GDB when running under Unix.
   2    Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1999, 2000,
   3    2001
   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 /* FIXME, some 387-specific items of use taken from i387-tdep.c -- ought to be
  24    merged back in. */
  25
  26 #include "defs.h"
  27 #include "frame.h"
  28 #include "inferior.h"
  29 #include "symtab.h"
  30 #include "target.h"
  31 #include "regcache.h"
  32
  33 /* FIXME: What is the _INKERNEL define for?  */
  34 #define _INKERNEL
  35 #include <signal.h>
  36 #undef _INKERNEL
  37 #include <sys/wait.h>
  38 #include <sys/param.h>
  39 #include <sys/user.h>
  40 #include <sys/proc.h>
  41 #include <sys/dir.h>
  42 #include <sys/ioctl.h>
  43 #include "gdb_stat.h"
  44 #ifdef _SEQUENT_
  45 #include <sys/ptrace.h>
  46 #else
  47 /* Dynix has only machine/ptrace.h, which is already included by sys/user.h  */
  48 /* Dynix has no mptrace call */
  49 #define mptrace ptrace
  50 #endif
  51 #include "gdbcore.h"
  52 #include <fcntl.h>
  53 #include <sgtty.h>
  54 #define TERMINAL struct sgttyb
  55
  56 #include "gdbcore.h"
  57
  58 void
  59 store_inferior_registers (int regno)
  60 {
  61   struct pt_regset regs;
  62   int i;
  63
  64   /* FIXME: Fetching the registers is a kludge to initialize all elements
  65      in the fpu and fpa status. This works for normal debugging, but
  66      might cause problems when calling functions in the inferior.
  67      At least fpu_control and fpa_pcr (probably more) should be added
  68      to the registers array to solve this properly.  */
  69   mptrace (XPT_RREGS, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) & regs, 0);
  70
  71   regs.pr_eax = *(int *) &registers[REGISTER_BYTE (0)];
  72   regs.pr_ebx = *(int *) &registers[REGISTER_BYTE (5)];
  73   regs.pr_ecx = *(int *) &registers[REGISTER_BYTE (2)];
  74   regs.pr_edx = *(int *) &registers[REGISTER_BYTE (1)];
  75   regs.pr_esi = *(int *) &registers[REGISTER_BYTE (6)];
  76   regs.pr_edi = *(int *) &registers[REGISTER_BYTE (7)];
  77   regs.pr_esp = *(int *) &registers[REGISTER_BYTE (14)];
  78   regs.pr_ebp = *(int *) &registers[REGISTER_BYTE (15)];
  79   regs.pr_eip = *(int *) &registers[REGISTER_BYTE (16)];
  80   regs.pr_flags = *(int *) &registers[REGISTER_BYTE (17)];
  81   for (i = 0; i < 31; i++)
  82     {
  83       regs.pr_fpa.fpa_regs[i] =
  84         *(int *) &registers[REGISTER_BYTE (FP1_REGNUM + i)];
  85     }
  86   memcpy (regs.pr_fpu.fpu_stack[0], &registers[REGISTER_BYTE (ST0_REGNUM)], 10);
  87   memcpy (regs.pr_fpu.fpu_stack[1], &registers[REGISTER_BYTE (ST1_REGNUM)], 10);
  88   memcpy (regs.pr_fpu.fpu_stack[2], &registers[REGISTER_BYTE (ST2_REGNUM)], 10);
  89   memcpy (regs.pr_fpu.fpu_stack[3], &registers[REGISTER_BYTE (ST3_REGNUM)], 10);
  90   memcpy (regs.pr_fpu.fpu_stack[4], &registers[REGISTER_BYTE (ST4_REGNUM)], 10);
  91   memcpy (regs.pr_fpu.fpu_stack[5], &registers[REGISTER_BYTE (ST5_REGNUM)], 10);
  92   memcpy (regs.pr_fpu.fpu_stack[6], &registers[REGISTER_BYTE (ST6_REGNUM)], 10);
  93   memcpy (regs.pr_fpu.fpu_stack[7], &registers[REGISTER_BYTE (ST7_REGNUM)], 10);
  94   mptrace (XPT_WREGS, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) & regs, 0);
  95 }
  96
  97 void
  98 fetch_inferior_registers (int regno)
  99 {
 100   int i;
 101   struct pt_regset regs;
 102
 103   registers_fetched ();
 104
 105   mptrace (XPT_RREGS, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) & regs, 0);
 106   *(int *) &registers[REGISTER_BYTE (EAX_REGNUM)] = regs.pr_eax;
 107   *(int *) &registers[REGISTER_BYTE (EBX_REGNUM)] = regs.pr_ebx;
 108   *(int *) &registers[REGISTER_BYTE (ECX_REGNUM)] = regs.pr_ecx;
 109   *(int *) &registers[REGISTER_BYTE (EDX_REGNUM)] = regs.pr_edx;
 110   *(int *) &registers[REGISTER_BYTE (ESI_REGNUM)] = regs.pr_esi;
 111   *(int *) &registers[REGISTER_BYTE (EDI_REGNUM)] = regs.pr_edi;
 112   *(int *) &registers[REGISTER_BYTE (EBP_REGNUM)] = regs.pr_ebp;
 113   *(int *) &registers[REGISTER_BYTE (ESP_REGNUM)] = regs.pr_esp;
 114   *(int *) &registers[REGISTER_BYTE (EIP_REGNUM)] = regs.pr_eip;
 115   *(int *) &registers[REGISTER_BYTE (EFLAGS_REGNUM)] = regs.pr_flags;
 116   for (i = 0; i < FPA_NREGS; i++)
 117     {
 118       *(int *) &registers[REGISTER_BYTE (FP1_REGNUM + i)] =
 119         regs.pr_fpa.fpa_regs[i];
 120     }
 121   memcpy (&registers[REGISTER_BYTE (ST0_REGNUM)], regs.pr_fpu.fpu_stack[0], 10);
 122   memcpy (&registers[REGISTER_BYTE (ST1_REGNUM)], regs.pr_fpu.fpu_stack[1], 10);
 123   memcpy (&registers[REGISTER_BYTE (ST2_REGNUM)], regs.pr_fpu.fpu_stack[2], 10);
 124   memcpy (&registers[REGISTER_BYTE (ST3_REGNUM)], regs.pr_fpu.fpu_stack[3], 10);
 125   memcpy (&registers[REGISTER_BYTE (ST4_REGNUM)], regs.pr_fpu.fpu_stack[4], 10);
 126   memcpy (&registers[REGISTER_BYTE (ST5_REGNUM)], regs.pr_fpu.fpu_stack[5], 10);
 127   memcpy (&registers[REGISTER_BYTE (ST6_REGNUM)], regs.pr_fpu.fpu_stack[6], 10);
 128   memcpy (&registers[REGISTER_BYTE (ST7_REGNUM)], regs.pr_fpu.fpu_stack[7], 10);
 129 }
 130 \f
 131 /* FIXME:  This should be merged with i387-tdep.c as well. */
 132 static
 133 print_fpu_status (struct pt_regset ep)
 134 {
 135   int i;
 136   int bothstatus;
 137   int top;
 138   int fpreg;
 139   unsigned char *p;
 140
 141   printf_unfiltered ("80387:");
 142   if (ep.pr_fpu.fpu_ip == 0)
 143     {
 144       printf_unfiltered (" not in use.\n");
 145       return;
 146     }
 147   else
 148     {
 149       printf_unfiltered ("\n");
 150     }
 151   if (ep.pr_fpu.fpu_status != 0)
 152     {
 153       print_387_status_word (ep.pr_fpu.fpu_status);
 154     }
 155   print_387_control_word (ep.pr_fpu.fpu_control);
 156   printf_unfiltered ("last exception: ");
 157   printf_unfiltered ("opcode 0x%x; ", ep.pr_fpu.fpu_rsvd4);
 158   printf_unfiltered ("pc 0x%x:0x%x; ", ep.pr_fpu.fpu_cs, ep.pr_fpu.fpu_ip);
 159   printf_unfiltered ("operand 0x%x:0x%x\n", ep.pr_fpu.fpu_data_offset, ep.pr_fpu.fpu_op_sel);
 160
 161   top = (ep.pr_fpu.fpu_status >> 11) & 7;
 162
 163   printf_unfiltered ("regno  tag  msb              lsb  value\n");
 164   for (fpreg = 7; fpreg >= 0; fpreg--)
 165     {
 166       double val;
 167
 168       printf_unfiltered ("%s %d: ", fpreg == top ? "=>" : "  ", fpreg);
 169
 170       switch ((ep.pr_fpu.fpu_tag >> (fpreg * 2)) & 3)
 171         {
 172         case 0:
 173           printf_unfiltered ("valid ");
 174           break;
 175         case 1:
 176           printf_unfiltered ("zero  ");
 177           break;
 178         case 2:
 179           printf_unfiltered ("trap  ");
 180           break;
 181         case 3:
 182           printf_unfiltered ("empty ");
 183           break;
 184         }
 185       for (i = 9; i >= 0; i--)
 186         printf_unfiltered ("%02x", ep.pr_fpu.fpu_stack[fpreg][i]);
 187
 188       i387_to_double ((char *) ep.pr_fpu.fpu_stack[fpreg], (char *) &val);
 189       printf_unfiltered ("  %g\n", val);
 190     }
 191   if (ep.pr_fpu.fpu_rsvd1)
 192     warning ("rsvd1 is 0x%x\n", ep.pr_fpu.fpu_rsvd1);
 193   if (ep.pr_fpu.fpu_rsvd2)
 194     warning ("rsvd2 is 0x%x\n", ep.pr_fpu.fpu_rsvd2);
 195   if (ep.pr_fpu.fpu_rsvd3)
 196     warning ("rsvd3 is 0x%x\n", ep.pr_fpu.fpu_rsvd3);
 197   if (ep.pr_fpu.fpu_rsvd5)
 198     warning ("rsvd5 is 0x%x\n", ep.pr_fpu.fpu_rsvd5);
 199 }
 200
 201
 202 print_1167_control_word (unsigned int pcr)
 203 {
 204   int pcr_tmp;
 205
 206   pcr_tmp = pcr & FPA_PCR_MODE;
 207   printf_unfiltered ("\tMODE= %#x; RND= %#x ", pcr_tmp, pcr_tmp & 12);
 208   switch (pcr_tmp & 12)
 209     {
 210     case 0:
 211       printf_unfiltered ("RN (Nearest Value)");
 212       break;
 213     case 1:
 214       printf_unfiltered ("RZ (Zero)");
 215       break;
 216     case 2:
 217       printf_unfiltered ("RP (Positive Infinity)");
 218       break;
 219     case 3:
 220       printf_unfiltered ("RM (Negative Infinity)");
 221       break;
 222     }
 223   printf_unfiltered ("; IRND= %d ", pcr_tmp & 2);
 224   if (0 == pcr_tmp & 2)
 225     {
 226       printf_unfiltered ("(same as RND)\n");
 227     }
 228   else
 229     {
 230       printf_unfiltered ("(toward zero)\n");
 231     }
 232   pcr_tmp = pcr & FPA_PCR_EM;
 233   printf_unfiltered ("\tEM= %#x", pcr_tmp);
 234   if (pcr_tmp & FPA_PCR_EM_DM)
 235     printf_unfiltered (" DM");
 236   if (pcr_tmp & FPA_PCR_EM_UOM)
 237     printf_unfiltered (" UOM");
 238   if (pcr_tmp & FPA_PCR_EM_PM)
 239     printf_unfiltered (" PM");
 240   if (pcr_tmp & FPA_PCR_EM_UM)
 241     printf_unfiltered (" UM");
 242   if (pcr_tmp & FPA_PCR_EM_OM)
 243     printf_unfiltered (" OM");
 244   if (pcr_tmp & FPA_PCR_EM_ZM)
 245     printf_unfiltered (" ZM");
 246   if (pcr_tmp & FPA_PCR_EM_IM)
 247     printf_unfiltered (" IM");
 248   printf_unfiltered ("\n");
 249   pcr_tmp = FPA_PCR_CC;
 250   printf_unfiltered ("\tCC= %#x", pcr_tmp);
 251   if (pcr_tmp & FPA_PCR_20MHZ)
 252     printf_unfiltered (" 20MHZ");
 253   if (pcr_tmp & FPA_PCR_CC_Z)
 254     printf_unfiltered (" Z");
 255   if (pcr_tmp & FPA_PCR_CC_C2)
 256     printf_unfiltered (" C2");
 257
 258   /* Dynix defines FPA_PCR_CC_C0 to 0x100 and ptx defines
 259      FPA_PCR_CC_C1 to 0x100.  Use whichever is defined and assume
 260      the OS knows what it is doing.  */
 261 #ifdef FPA_PCR_CC_C1
 262   if (pcr_tmp & FPA_PCR_CC_C1)
 263     printf_unfiltered (" C1");
 264 #else
 265   if (pcr_tmp & FPA_PCR_CC_C0)
 266     printf_unfiltered (" C0");
 267 #endif
 268
 269   switch (pcr_tmp)
 270     {
 271     case FPA_PCR_CC_Z:
 272       printf_unfiltered (" (Equal)");
 273       break;
 274 #ifdef FPA_PCR_CC_C1
 275     case FPA_PCR_CC_C1:
 276 #else
 277     case FPA_PCR_CC_C0:
 278 #endif
 279       printf_unfiltered (" (Less than)");
 280       break;
 281     case 0:
 282       printf_unfiltered (" (Greater than)");
 283       break;
 284       case FPA_PCR_CC_Z |
 285 #ifdef FPA_PCR_CC_C1
 286         FPA_PCR_CC_C1
 287 #else
 288         FPA_PCR_CC_C0
 289 #endif
 290     | FPA_PCR_CC_C2:
 291       printf_unfiltered (" (Unordered)");
 292       break;
 293     default:
 294       printf_unfiltered (" (Undefined)");
 295       break;
 296     }
 297   printf_unfiltered ("\n");
 298   pcr_tmp = pcr & FPA_PCR_AE;
 299   printf_unfiltered ("\tAE= %#x", pcr_tmp);
 300   if (pcr_tmp & FPA_PCR_AE_DE)
 301     printf_unfiltered (" DE");
 302   if (pcr_tmp & FPA_PCR_AE_UOE)
 303     printf_unfiltered (" UOE");
 304   if (pcr_tmp & FPA_PCR_AE_PE)
 305     printf_unfiltered (" PE");
 306   if (pcr_tmp & FPA_PCR_AE_UE)
 307     printf_unfiltered (" UE");
 308   if (pcr_tmp & FPA_PCR_AE_OE)
 309     printf_unfiltered (" OE");
 310   if (pcr_tmp & FPA_PCR_AE_ZE)
 311     printf_unfiltered (" ZE");
 312   if (pcr_tmp & FPA_PCR_AE_EE)
 313     printf_unfiltered (" EE");
 314   if (pcr_tmp & FPA_PCR_AE_IE)
 315     printf_unfiltered (" IE");
 316   printf_unfiltered ("\n");
 317 }
 318
 319 print_1167_regs (long regs[FPA_NREGS])
 320 {
 321   int i;
 322
 323   union
 324     {
 325       double d;
 326       long l[2];
 327     }
 328   xd;
 329   union
 330     {
 331       float f;
 332       long l;
 333     }
 334   xf;
 335
 336
 337   for (i = 0; i < FPA_NREGS; i++)
 338     {
 339       xf.l = regs[i];
 340       printf_unfiltered ("%%fp%d: raw= %#x, single= %f", i + 1, regs[i], xf.f);
 341       if (!(i & 1))
 342         {
 343           printf_unfiltered ("\n");
 344         }
 345       else
 346         {
 347           xd.l[1] = regs[i];
 348           xd.l[0] = regs[i + 1];
 349           printf_unfiltered (", double= %f\n", xd.d);
 350         }
 351     }
 352 }
 353
 354 print_fpa_status (struct pt_regset ep)
 355 {
 356
 357   printf_unfiltered ("WTL 1167:");
 358   if (ep.pr_fpa.fpa_pcr != 0)
 359     {
 360       printf_unfiltered ("\n");
 361       print_1167_control_word (ep.pr_fpa.fpa_pcr);
 362       print_1167_regs (ep.pr_fpa.fpa_regs);
 363     }
 364   else
 365     {
 366       printf_unfiltered (" not in use.\n");
 367     }
 368 }
 369
 370 #if 0                           /* disabled because it doesn't go through the target vector.  */
 371 i386_float_info (void)
 372 {
 373   char ubuf[UPAGES * NBPG];
 374   struct pt_regset regset;
 375
 376   if (have_inferior_p ())
 377     {
 378       PTRACE_READ_REGS (PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) & regset);
 379     }
 380   else
 381     {
 382       int corechan = bfd_cache_lookup (core_bfd);
 383       if (lseek (corechan, 0, 0) < 0)
 384         {
 385           perror ("seek on core file");
 386         }
 387       if (myread (corechan, ubuf, UPAGES * NBPG) < 0)
 388         {
 389           perror ("read on core file");
 390         }
 391       /* only interested in the floating point registers */
 392       regset.pr_fpu = ((struct user *) ubuf)->u_fpusave;
 393       regset.pr_fpa = ((struct user *) ubuf)->u_fpasave;
 394     }
 395   print_fpu_status (regset);
 396   print_fpa_status (regset);
 397 }
 398 #endif
 399
 400 static volatile int got_sigchld;
 401
 402 /*ARGSUSED */
 403 /* This will eventually be more interesting. */
 404 void
 405 sigchld_handler (int signo)
 406 {
 407   got_sigchld++;
 408 }
 409
 410 /*
 411  * Signals for which the default action does not cause the process
 412  * to die.  See <sys/signal.h> for where this came from (alas, we
 413  * can't use those macros directly)
 414  */
 415 #ifndef sigmask
 416 #define sigmask(s) (1 << ((s) - 1))
 417 #endif
 418 #define SIGNALS_DFL_SAFE sigmask(SIGSTOP) | sigmask(SIGTSTP) | \
 419         sigmask(SIGTTIN) | sigmask(SIGTTOU) | sigmask(SIGCHLD) | \
 420         sigmask(SIGCONT) | sigmask(SIGWINCH) | sigmask(SIGPWR) | \
 421         sigmask(SIGURG) | sigmask(SIGPOLL)
 422
 423 #ifdef ATTACH_DETACH
 424 /*
 425  * Thanks to XPT_MPDEBUGGER, we have to mange child_wait().
 426  */
 427 ptid_t
 428 child_wait (ptid_t ptid, struct target_waitstatus *status)
 429 {
 430   int save_errno, rv, xvaloff, saoff, sa_hand;
 431   struct pt_stop pt;
 432   struct user u;
 433   sigset_t set;
 434   /* Host signal number for a signal which the inferior terminates with, or
 435      0 if it hasn't terminated due to a signal.  */
 436   static int death_by_signal = 0;
 437 #ifdef SVR4_SHARED_LIBS         /* use this to distinguish ptx 2 vs ptx 4 */
 438   prstatus_t pstatus;
 439 #endif
 440   int pid = PIDGET (ptid);
 441
 442   do
 443     {
 444       set_sigint_trap ();       /* Causes SIGINT to be passed on to the
 445                                    attached process. */
 446       save_errno = errno;
 447
 448       got_sigchld = 0;
 449
 450       sigemptyset (&set);
 451
 452       while (got_sigchld == 0)
 453         {
 454           sigsuspend (&set);
 455         }
 456
 457       clear_sigint_trap ();
 458
 459       rv = mptrace (XPT_STOPSTAT, 0, (char *) &pt, 0);
 460       if (-1 == rv)
 461         {
 462           printf ("XPT_STOPSTAT: errno %d\n", errno);   /* DEBUG */
 463           continue;
 464         }
 465
 466       pid = pt.ps_pid;
 467
 468       if (pid != PIDGET (inferior_ptid))
 469         {
 470           /* NOTE: the mystery fork in csh/tcsh needs to be ignored.
 471            * We should not return new children for the initial run
 472            * of a process until it has done the exec.
 473            */
 474           /* inferior probably forked; send it on its way */
 475           rv = mptrace (XPT_UNDEBUG, pid, 0, 0);
 476           if (-1 == rv)
 477             {
 478               printf ("child_wait: XPT_UNDEBUG: pid %d: %s\n", pid,
 479                       safe_strerror (errno));
 480             }
 481           continue;
 482         }
 483       /* FIXME: Do we deal with fork notification correctly?  */
 484       switch (pt.ps_reason)
 485         {
 486         case PTS_FORK:
 487           /* multi proc: treat like PTS_EXEC */
 488           /*
 489            * Pretend this didn't happen, since gdb isn't set up
 490            * to deal with stops on fork.
 491            */
 492           rv = ptrace (PT_CONTSIG, pid, 1, 0);
 493           if (-1 == rv)
 494             {
 495               printf ("PTS_FORK: PT_CONTSIG: error %d\n", errno);
 496             }
 497           continue;
 498         case PTS_EXEC:
 499           /*
 500            * Pretend this is a SIGTRAP.
 501            */
 502           status->kind = TARGET_WAITKIND_STOPPED;
 503           status->value.sig = TARGET_SIGNAL_TRAP;
 504           break;
 505         case PTS_EXIT:
 506           /*
 507            * Note: we stop before the exit actually occurs.  Extract
 508            * the exit code from the uarea.  If we're stopped in the
 509            * exit() system call, the exit code will be in
 510            * u.u_ap[0].  An exit due to an uncaught signal will have
 511            * something else in here, see the comment in the default:
 512            * case, below.  Finally,let the process exit.
 513            */
 514           if (death_by_signal)
 515             {
 516               status->kind = TARGET_WAITKIND_SIGNALED;
 517               status->value.sig = target_signal_from_host (death_by_signal);
 518               death_by_signal = 0;
 519               break;
 520             }
 521           xvaloff = (unsigned long) &u.u_ap[0] - (unsigned long) &u;
 522           errno = 0;
 523           rv = ptrace (PT_RUSER, pid, (char *) xvaloff, 0);
 524           status->kind = TARGET_WAITKIND_EXITED;
 525           status->value.integer = rv;
 526           /*
 527            * addr & data to mptrace() don't matter here, since
 528            * the process is already dead.
 529            */
 530           rv = mptrace (XPT_UNDEBUG, pid, 0, 0);
 531           if (-1 == rv)
 532             {
 533               printf ("child_wait: PTS_EXIT: XPT_UNDEBUG: pid %d error %d\n", pid,
 534                       errno);
 535             }
 536           break;
 537         case PTS_WATCHPT_HIT:
 538           internal_error (__FILE__, __LINE__,
 539                           "PTS_WATCHPT_HIT\n");
 540           break;
 541         default:
 542           /* stopped by signal */
 543           status->kind = TARGET_WAITKIND_STOPPED;
 544           status->value.sig = target_signal_from_host (pt.ps_reason);
 545           death_by_signal = 0;
 546
 547           if (0 == (SIGNALS_DFL_SAFE & sigmask (pt.ps_reason)))
 548             {
 549               break;
 550             }
 551           /* else default action of signal is to die */
 552 #ifdef SVR4_SHARED_LIBS
 553           rv = ptrace (PT_GET_PRSTATUS, pid, (char *) &pstatus, 0);
 554           if (-1 == rv)
 555             error ("child_wait: signal %d PT_GET_PRSTATUS: %s\n",
 556                    pt.ps_reason, safe_strerror (errno));
 557           if (pstatus.pr_cursig != pt.ps_reason)
 558             {
 559               printf ("pstatus signal %d, pt signal %d\n",
 560                       pstatus.pr_cursig, pt.ps_reason);
 561             }
 562           sa_hand = (int) pstatus.pr_action.sa_handler;
 563 #else
 564           saoff = (unsigned long) &u.u_sa[0] - (unsigned long) &u;
 565           saoff += sizeof (struct sigaction) * (pt.ps_reason - 1);
 566           errno = 0;
 567           sa_hand = ptrace (PT_RUSER, pid, (char *) saoff, 0);
 568           if (errno)
 569             error ("child_wait: signal %d: RUSER: %s\n",
 570                    pt.ps_reason, safe_strerror (errno));
 571 #endif
 572           if ((int) SIG_DFL == sa_hand)
 573             {
 574               /* we will be dying */
 575               death_by_signal = pt.ps_reason;
 576             }
 577           break;
 578         }
 579
 580     }
 581   while (pid != PIDGET (inferior_ptid));        /* Some other child died or stopped */
 582
 583   return pid_to_ptid (pid);
 584 }
 585 #else /* !ATTACH_DETACH */
 586 /*
 587  * Simple child_wait() based on inftarg.c child_wait() for use until
 588  * the MPDEBUGGER child_wait() works properly.  This will go away when
 589  * that is fixed.
 590  */
 591 ptid_t
 592 child_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
 593 {
 594   int save_errno;
 595   int status;
 596   int pid = PIDGET (ptid);
 597
 598   do
 599     {
 600       pid = wait (&status);
 601       save_errno = errno;
 602
 603       if (pid == -1)
 604         {
 605           if (save_errno == EINTR)
 606             continue;
 607           fprintf (stderr, "Child process unexpectedly missing: %s.\n",
 608                    safe_strerror (save_errno));
 609           ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
 610           ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
 611           return pid_to_ptid (-1);
 612         }
 613     }
 614   while (pid != PIDGET (inferior_ptid));        /* Some other child died or stopped */
 615   store_waitstatus (ourstatus, status);
 616   return pid_to_ptid (pid);
 617 }
 618 #endif /* ATTACH_DETACH */
 619 \f
 620
 621
 622 /* This function simply calls ptrace with the given arguments.
 623    It exists so that all calls to ptrace are isolated in this
 624    machine-dependent file. */
 625 int
 626 call_ptrace (int request, int pid, PTRACE_ARG3_TYPE addr, int data)
 627 {
 628   return ptrace (request, pid, addr, data);
 629 }
 630
 631 int
 632 call_mptrace (int request, int pid, PTRACE_ARG3_TYPE addr, int data)
 633 {
 634   return mptrace (request, pid, addr, data);
 635 }
 636
 637 #if defined (DEBUG_PTRACE)
 638 /* For the rest of the file, use an extra level of indirection */
 639 /* This lets us breakpoint usefully on call_ptrace. */
 640 #define ptrace call_ptrace
 641 #define mptrace call_mptrace
 642 #endif
 643
 644 void
 645 kill_inferior (void)
 646 {
 647   if (ptid_equal (inferior_ptid, null_ptid))
 648     return;
 649
 650   /* For MPDEBUGGER, don't use PT_KILL, since the child will stop
 651      again with a PTS_EXIT.  Just hit him with SIGKILL (so he stops)
 652      and detach. */
 653
 654   kill (PIDGET (inferior_ptid), SIGKILL);
 655 #ifdef ATTACH_DETACH
 656   detach (SIGKILL);
 657 #else /* ATTACH_DETACH */
 658   ptrace (PT_KILL, PIDGET (inferior_ptid), 0, 0);
 659   wait ((int *) NULL);
 660 #endif /* ATTACH_DETACH */
 661   target_mourn_inferior ();
 662 }
 663
 664 /* Resume execution of the inferior process.
 665    If STEP is nonzero, single-step it.
 666    If SIGNAL is nonzero, give it that signal.  */
 667
 668 void
 669 child_resume (ptid_t ptid, int step, enum target_signal signal)
 670 {
 671   int pid = PIDGET (ptid);
 672
 673   errno = 0;
 674
 675   if (pid == -1)
 676     pid = PIDGET (inferior_ptid);
 677
 678   /* An address of (PTRACE_ARG3_TYPE)1 tells ptrace to continue from where
 679      it was.  (If GDB wanted it to start some other way, we have already
 680      written a new PC value to the child.)
 681
 682      If this system does not support PT_SSTEP, a higher level function will
 683      have called single_step() to transmute the step request into a
 684      continue request (by setting breakpoints on all possible successor
 685      instructions), so we don't have to worry about that here.  */
 686
 687   if (step)
 688     ptrace (PT_SSTEP, pid, (PTRACE_ARG3_TYPE) 1, signal);
 689   else
 690     ptrace (PT_CONTSIG, pid, (PTRACE_ARG3_TYPE) 1, signal);
 691
 692   if (errno)
 693     perror_with_name ("ptrace");
 694 }
 695 \f
 696 #ifdef ATTACH_DETACH
 697 /* Start debugging the process whose number is PID.  */
 698 int
 699 attach (int pid)
 700 {
 701   sigset_t set;
 702   int rv;
 703
 704   rv = mptrace (XPT_DEBUG, pid, 0, 0);
 705   if (-1 == rv)
 706     {
 707       error ("mptrace(XPT_DEBUG): %s", safe_strerror (errno));
 708     }
 709   rv = mptrace (XPT_SIGNAL, pid, 0, SIGSTOP);
 710   if (-1 == rv)
 711     {
 712       error ("mptrace(XPT_SIGNAL): %s", safe_strerror (errno));
 713     }
 714   attach_flag = 1;
 715   return pid;
 716 }
 717
 718 void
 719 detach (int signo)
 720 {
 721   int rv;
 722
 723   rv = mptrace (XPT_UNDEBUG, PIDGET (inferior_ptid), 1, signo);
 724   if (-1 == rv)
 725     {
 726       error ("mptrace(XPT_UNDEBUG): %s", safe_strerror (errno));
 727     }
 728   attach_flag = 0;
 729 }
 730
 731 #endif /* ATTACH_DETACH */
 732 \f
 733 /* Default the type of the ptrace transfer to int.  */
 734 #ifndef PTRACE_XFER_TYPE
 735 #define PTRACE_XFER_TYPE int
 736 #endif
 737 \f
 738
 739 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
 740    in the NEW_SUN_PTRACE case.
 741    It ought to be straightforward.  But it appears that writing did
 742    not write the data that I specified.  I cannot understand where
 743    it got the data that it actually did write.  */
 744
 745 /* Copy LEN bytes to or from inferior's memory starting at MEMADDR
 746    to debugger memory starting at MYADDR.   Copy to inferior if
 747    WRITE is nonzero.  TARGET is ignored.
 748
 749    Returns the length copied, which is either the LEN argument or zero.
 750    This xfer function does not do partial moves, since child_ops
 751    doesn't allow memory operations to cross below us in the target stack
 752    anyway.  */
 753
 754 int
 755 child_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
 756                    struct mem_attrib *attrib,
 757                    struct target_ops *target)
 758 {
 759   register int i;
 760   /* Round starting address down to longword boundary.  */
 761   register CORE_ADDR addr = memaddr & -sizeof (PTRACE_XFER_TYPE);
 762   /* Round ending address up; get number of longwords that makes.  */
 763   register int count
 764   = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
 765   / sizeof (PTRACE_XFER_TYPE);
 766   /* Allocate buffer of that many longwords.  */
 767   register PTRACE_XFER_TYPE *buffer
 768   = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
 769
 770   if (write)
 771     {
 772       /* Fill start and end extra bytes of buffer with existing memory data.  */
 773
 774       if (addr != memaddr || len < (int) sizeof (PTRACE_XFER_TYPE))
 775         {
 776           /* Need part of initial word -- fetch it.  */
 777           buffer[0] = ptrace (PT_RTEXT, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) addr,
 778                               0);
 779         }
 780
 781       if (count > 1)            /* FIXME, avoid if even boundary */
 782         {
 783           buffer[count - 1]
 784             = ptrace (PT_RTEXT, PIDGET (inferior_ptid),
 785                       ((PTRACE_ARG3_TYPE)
 786                        (addr + (count - 1) * sizeof (PTRACE_XFER_TYPE))),
 787                       0);
 788         }
 789
 790       /* Copy data to be written over corresponding part of buffer */
 791
 792       memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
 793               myaddr,
 794               len);
 795
 796       /* Write the entire buffer.  */
 797
 798       for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
 799         {
 800           errno = 0;
 801           ptrace (PT_WDATA, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) addr,
 802                   buffer[i]);
 803           if (errno)
 804             {
 805               /* Using the appropriate one (I or D) is necessary for
 806                  Gould NP1, at least.  */
 807               errno = 0;
 808               ptrace (PT_WTEXT, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) addr,
 809                       buffer[i]);
 810             }
 811           if (errno)
 812             return 0;
 813         }
 814     }
 815   else
 816     {
 817       /* Read all the longwords */
 818       for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
 819         {
 820           errno = 0;
 821           buffer[i] = ptrace (PT_RTEXT, PIDGET (inferior_ptid),
 822                               (PTRACE_ARG3_TYPE) addr, 0);
 823           if (errno)
 824             return 0;
 825           QUIT;
 826         }
 827
 828       /* Copy appropriate bytes out of the buffer.  */
 829       memcpy (myaddr,
 830               (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
 831               len);
 832     }
 833   return len;
 834 }
 835
 836
 837 void
 838 _initialize_symm_nat (void)
 839 {
 840 #ifdef ATTACH_DETACH
 841 /*
 842  * the MPDEBUGGER is necessary for process tree debugging and attach
 843  * to work, but it alters the behavior of debugged processes, so other
 844  * things (at least child_wait()) will have to change to accomodate
 845  * that.
 846  *
 847  * Note that attach is not implemented in dynix 3, and not in ptx
 848  * until version 2.1 of the OS.
 849  */
 850   int rv;
 851   sigset_t set;
 852   struct sigaction sact;
 853
 854   rv = mptrace (XPT_MPDEBUGGER, 0, 0, 0);
 855   if (-1 == rv)
 856     {
 857       internal_error (__FILE__, __LINE__,
 858                       "_initialize_symm_nat(): mptrace(XPT_MPDEBUGGER): %s",
 859                       safe_strerror (errno));
 860     }
 861
 862   /*
 863    * Under MPDEBUGGER, we get SIGCLHD when a traced process does
 864    * anything of interest.
 865    */
 866
 867   /*
 868    * Block SIGCHLD.  We leave it blocked all the time, and then
 869    * call sigsuspend() in child_wait() to wait for the child
 870    * to do something.  None of these ought to fail, but check anyway.
 871    */
 872   sigemptyset (&set);
 873   rv = sigaddset (&set, SIGCHLD);
 874   if (-1 == rv)
 875     {
 876       internal_error (__FILE__, __LINE__,
 877                       "_initialize_symm_nat(): sigaddset(SIGCHLD): %s",
 878                       safe_strerror (errno));
 879     }
 880   rv = sigprocmask (SIG_BLOCK, &set, (sigset_t *) NULL);
 881   if (-1 == rv)
 882     {
 883       internal_error (__FILE__, __LINE__,
 884                       "_initialize_symm_nat(): sigprocmask(SIG_BLOCK): %s",
 885                       safe_strerror (errno));
 886     }
 887
 888   sact.sa_handler = sigchld_handler;
 889   sigemptyset (&sact.sa_mask);
 890   sact.sa_flags = SA_NOCLDWAIT; /* keep the zombies away */
 891   rv = sigaction (SIGCHLD, &sact, (struct sigaction *) NULL);
 892   if (-1 == rv)
 893     {
 894       internal_error (__FILE__, __LINE__,
 895                       "_initialize_symm_nat(): sigaction(SIGCHLD): %s",
 896                       safe_strerror (errno));
 897     }
 898 #endif
 899 }