gdb/gdbserver/low-hppabsd.c

   1 /* Low level interface to ptrace, for the remote server for GDB.
   2    Copyright (C) 1995 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,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "defs.h"
  22 #include <sys/wait.h>
  23 #include "frame.h"
  24 #include "inferior.h"
  25
  26 #include <stdio.h>
  27 #include <sys/param.h>
  28 #include <sys/dir.h>
  29 #include <sys/user.h>
  30 #include <signal.h>
  31 #include <sys/ioctl.h>
  32 #include <sgtty.h>
  33 #include <fcntl.h>
  34
  35 /***************Begin MY defs*********************/
  36 int quit_flag = 0;
  37 static char my_registers[REGISTER_BYTES];
  38 char *registers = my_registers;
  39
  40 /* Index within `registers' of the first byte of the space for
  41    register N.  */
  42
  43
  44 char buf2[MAX_REGISTER_RAW_SIZE];
  45 /***************End MY defs*********************/
  46
  47 #include <sys/ptrace.h>
  48 #include <machine/reg.h>
  49
  50 extern char **environ;
  51 extern int errno;
  52 extern int inferior_pid;
  53 void quit (), perror_with_name ();
  54 int query ();
  55
  56 /* Start an inferior process and returns its pid.
  57    ALLARGS is a vector of program-name and args.
  58    ENV is the environment vector to pass.  */
  59
  60 int
  61 create_inferior (program, allargs)
  62      char *program;
  63      char **allargs;
  64 {
  65   int pid;
  66
  67   pid = fork ();
  68   if (pid < 0)
  69     perror_with_name ("fork");
  70
  71   if (pid == 0)
  72     {
  73       ptrace (PT_TRACE_ME, 0, 0, 0, 0);
  74
  75       execv (program, allargs);
  76
  77       fprintf (stderr, "Cannot exec %s: %s.\n", program,
  78                errno < sys_nerr ? sys_errlist[errno] : "unknown error");
  79       fflush (stderr);
  80       _exit (0177);
  81     }
  82
  83   return pid;
  84 }
  85
  86 /* Kill the inferior process.  Make us have no inferior.  */
  87
  88 void
  89 kill_inferior ()
  90 {
  91   if (inferior_pid == 0)
  92     return;
  93   ptrace (8, inferior_pid, 0, 0, 0);
  94   wait (0);
  95 /*************inferior_died ();****VK**************/
  96 }
  97
  98 /* Return nonzero if the given thread is still alive.  */
  99 int
 100 mythread_alive (pid)
 101      int pid;
 102 {
 103   return 1;
 104 }
 105
 106 /* Wait for process, returns status */
 107
 108 unsigned char
 109 mywait (status)
 110      char *status;
 111 {
 112   int pid;
 113   union wait w;
 114
 115   pid = wait (&w);
 116   if (pid != inferior_pid)
 117     perror_with_name ("wait");
 118
 119   if (WIFEXITED (w))
 120     {
 121       fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
 122       *status = 'W';
 123       return ((unsigned char) WEXITSTATUS (w));
 124     }
 125   else if (!WIFSTOPPED (w))
 126     {
 127       fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
 128       *status = 'X';
 129       return ((unsigned char) WTERMSIG (w));
 130     }
 131
 132   fetch_inferior_registers (0);
 133
 134   *status = 'T';
 135   return ((unsigned char) WSTOPSIG (w));
 136 }
 137
 138 /* Resume execution of the inferior process.
 139    If STEP is nonzero, single-step it.
 140    If SIGNAL is nonzero, give it that signal.  */
 141
 142 void
 143 myresume (step, signal)
 144      int step;
 145      int signal;
 146 {
 147   errno = 0;
 148   ptrace (step ? PT_STEP : PT_CONTINUE, inferior_pid, 1, signal, 0);
 149   if (errno)
 150     perror_with_name ("ptrace");
 151 }
 152
 153
 154 #if !defined (offsetof)
 155 #define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
 156 #endif
 157
 158 /* U_REGS_OFFSET is the offset of the registers within the u area.  */
 159 #if !defined (U_REGS_OFFSET)
 160 #define U_REGS_OFFSET \
 161   ptrace (PT_READ_U, inferior_pid, \
 162           (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
 163     - KERNEL_U_ADDR
 164 #endif
 165
 166 CORE_ADDR
 167 register_addr (regno, blockend)
 168      int regno;
 169      CORE_ADDR blockend;
 170 {
 171   CORE_ADDR addr;
 172
 173   if (regno < 0 || regno >= ARCH_NUM_REGS)
 174     error ("Invalid register number %d.", regno);
 175
 176   REGISTER_U_ADDR (addr, blockend, regno);
 177
 178   return addr;
 179 }
 180
 181 /* Fetch one register.  */
 182
 183 static void
 184 fetch_register (regno)
 185      int regno;
 186 {
 187   register unsigned int regaddr;
 188   char buf[MAX_REGISTER_RAW_SIZE];
 189   register int i;
 190
 191   /* Offset of registers within the u area.  */
 192   unsigned int offset;
 193
 194   offset = U_REGS_OFFSET;
 195
 196   regaddr = register_addr (regno, offset);
 197   for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
 198     {
 199       errno = 0;
 200       *(int *) &registers[regno * 4 + i] = ptrace (PT_RUREGS, inferior_pid,
 201                                           (PTRACE_ARG3_TYPE) regaddr, 0, 0);
 202       regaddr += sizeof (int);
 203       if (errno != 0)
 204         {
 205           /* Warning, not error, in case we are attached; sometimes the
 206              kernel doesn't let us at the registers.  */
 207           char *err = strerror (errno);
 208           char *msg = alloca (strlen (err) + 128);
 209           sprintf (msg, "reading register %d: %s", regno, err);
 210           error (msg);
 211           goto error_exit;
 212         }
 213     }
 214 error_exit:;
 215 }
 216
 217 /* Fetch all registers, or just one, from the child process.  */
 218
 219 void
 220 fetch_inferior_registers (regno)
 221      int regno;
 222 {
 223   if (regno == -1 || regno == 0)
 224     for (regno = 0; regno < NUM_REGS; regno++)
 225       fetch_register (regno);
 226   else
 227     fetch_register (regno);
 228 }
 229
 230 /* Store our register values back into the inferior.
 231    If REGNO is -1, do this for all registers.
 232    Otherwise, REGNO specifies which register (so we can save time).  */
 233
 234 void
 235 store_inferior_registers (regno)
 236      int regno;
 237 {
 238   register unsigned int regaddr;
 239   char buf[80];
 240   extern char registers[];
 241   register int i;
 242   unsigned int offset = U_REGS_OFFSET;
 243   int scratch;
 244
 245   if (regno >= 0)
 246     {
 247       if (CANNOT_STORE_REGISTER (regno))
 248         return;
 249       regaddr = register_addr (regno, offset);
 250       errno = 0;
 251       if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM)
 252         {
 253           scratch = *(int *) &registers[REGISTER_BYTE (regno)] | 0x3;
 254           ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 255                   scratch, 0);
 256           if (errno != 0)
 257             {
 258               /* Error, even if attached.  Failing to write these two
 259                  registers is pretty serious.  */
 260               sprintf (buf, "writing register number %d", regno);
 261               perror_with_name (buf);
 262             }
 263         }
 264       else
 265         for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
 266           {
 267             errno = 0;
 268             ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 269                     *(int *) &registers[REGISTER_BYTE (regno) + i], 0);
 270             if (errno != 0)
 271               {
 272                 /* Warning, not error, in case we are attached; sometimes the
 273                    kernel doesn't let us at the registers.  */
 274                 char *err = strerror (errno);
 275                 char *msg = alloca (strlen (err) + 128);
 276                 sprintf (msg, "writing register %d: %s",
 277                          regno, err);
 278                 error (msg);
 279                 return;
 280               }
 281             regaddr += sizeof (int);
 282           }
 283     }
 284   else
 285     for (regno = 0; regno < NUM_REGS; regno++)
 286       store_inferior_registers (regno);
 287 }
 288
 289 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
 290    in the NEW_SUN_PTRACE case.
 291    It ought to be straightforward.  But it appears that writing did
 292    not write the data that I specified.  I cannot understand where
 293    it got the data that it actually did write.  */
 294
 295 /* Copy LEN bytes from inferior's memory starting at MEMADDR
 296    to debugger memory starting at MYADDR.  */
 297
 298 read_inferior_memory (memaddr, myaddr, len)
 299      CORE_ADDR memaddr;
 300      char *myaddr;
 301      int len;
 302 {
 303   register int i;
 304   /* Round starting address down to longword boundary.  */
 305   register CORE_ADDR addr = memaddr & -sizeof (int);
 306   /* Round ending address up; get number of longwords that makes.  */
 307   register int count
 308   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 309   /* Allocate buffer of that many longwords.  */
 310   register int *buffer = (int *) alloca (count * sizeof (int));
 311
 312   /* Read all the longwords */
 313   for (i = 0; i < count; i++, addr += sizeof (int))
 314     {
 315       buffer[i] = ptrace (1, inferior_pid, addr, 0, 0);
 316     }
 317
 318   /* Copy appropriate bytes out of the buffer.  */
 319   memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
 320 }
 321
 322 /* Copy LEN bytes of data from debugger memory at MYADDR
 323    to inferior's memory at MEMADDR.
 324    On failure (cannot write the inferior)
 325    returns the value of errno.  */
 326
 327 int
 328 write_inferior_memory (memaddr, myaddr, len)
 329      CORE_ADDR memaddr;
 330      char *myaddr;
 331      int len;
 332 {
 333   register int i;
 334   /* Round starting address down to longword boundary.  */
 335   register CORE_ADDR addr = memaddr & -sizeof (int);
 336   /* Round ending address up; get number of longwords that makes.  */
 337   register int count
 338   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 339   /* Allocate buffer of that many longwords.  */
 340   register int *buffer = (int *) alloca (count * sizeof (int));
 341   extern int errno;
 342
 343   /* Fill start and end extra bytes of buffer with existing memory data.  */
 344
 345   buffer[0] = ptrace (1, inferior_pid, addr, 0, 0);
 346
 347   if (count > 1)
 348     {
 349       buffer[count - 1]
 350         = ptrace (1, inferior_pid,
 351                   addr + (count - 1) * sizeof (int), 0, 0);
 352     }
 353
 354   /* Copy data to be written over corresponding part of buffer */
 355
 356   memcpy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
 357
 358   /* Write the entire buffer.  */
 359
 360   for (i = 0; i < count; i++, addr += sizeof (int))
 361     {
 362       errno = 0;
 363       ptrace (4, inferior_pid, addr, buffer[i], 0);
 364       if (errno)
 365         return errno;
 366     }
 367
 368   return 0;
 369 }
 370 \f
 371 void
 372 initialize_low ()
 373 {
 374 }