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, Boston, MA 02111-1307, USA.  */
  19
  20 #include "defs.h"
  21 #include <sys/wait.h>
  22 #include "frame.h"
  23 #include "inferior.h"
  24
  25 #include <stdio.h>
  26 #include <sys/param.h>
  27 #include <sys/dir.h>
  28 #include <sys/user.h>
  29 #include <signal.h>
  30 #include <sys/ioctl.h>
  31 #include <sgtty.h>
  32 #include <fcntl.h>
  33
  34 /***************Begin MY defs*********************/
  35 int quit_flag = 0;
  36 char registers[REGISTER_BYTES];
  37
  38 /* Index within `registers' of the first byte of the space for
  39    register N.  */
  40
  41
  42 char buf2[MAX_REGISTER_RAW_SIZE];
  43 /***************End MY defs*********************/
  44
  45 #include <sys/ptrace.h>
  46 #include <machine/reg.h>
  47
  48 extern char **environ;
  49 extern int errno;
  50 extern int inferior_pid;
  51 void quit (), perror_with_name ();
  52 int query ();
  53
  54 /* Start an inferior process and returns its pid.
  55    ALLARGS is a vector of program-name and args.
  56    ENV is the environment vector to pass.  */
  57
  58 int
  59 create_inferior (program, allargs)
  60      char *program;
  61      char **allargs;
  62 {
  63   int pid;
  64
  65   pid = fork ();
  66   if (pid < 0)
  67     perror_with_name ("fork");
  68
  69   if (pid == 0)
  70     {
  71       ptrace (PT_TRACE_ME, 0, 0, 0, 0);
  72
  73       execv (program, allargs);
  74
  75       fprintf (stderr, "Cannot exec %s: %s.\n", program,
  76                errno < sys_nerr ? sys_errlist[errno] : "unknown error");
  77       fflush (stderr);
  78       _exit (0177);
  79     }
  80
  81   return pid;
  82 }
  83
  84 /* Kill the inferior process.  Make us have no inferior.  */
  85
  86 void
  87 kill_inferior ()
  88 {
  89   if (inferior_pid == 0)
  90     return;
  91   ptrace (8, inferior_pid, 0, 0, 0);
  92   wait (0);
  93   /*************inferior_died ();****VK**************/
  94 }
  95
  96 /* Return nonzero if the given thread is still alive.  */
  97 int
  98 mythread_alive (pid)
  99      int pid;
 100 {
 101   return 1;
 102 }
 103
 104 /* Wait for process, returns status */
 105
 106 unsigned char
 107 mywait (status)
 108      char *status;
 109 {
 110   int pid;
 111   union wait w;
 112
 113   pid = wait (&w);
 114   if (pid != inferior_pid)
 115     perror_with_name ("wait");
 116
 117   if (WIFEXITED (w))
 118     {
 119       fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
 120       *status = 'W';
 121       return ((unsigned char) WEXITSTATUS (w));
 122     }
 123   else if (!WIFSTOPPED (w))
 124     {
 125       fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
 126       *status = 'X';
 127       return ((unsigned char) WTERMSIG (w));
 128     }
 129
 130   fetch_inferior_registers (0);
 131
 132   *status = 'T';
 133   return ((unsigned char) WSTOPSIG (w));
 134 }
 135
 136 /* Resume execution of the inferior process.
 137    If STEP is nonzero, single-step it.
 138    If SIGNAL is nonzero, give it that signal.  */
 139
 140 void
 141 myresume (step, signal)
 142      int step;
 143      int signal;
 144 {
 145   errno = 0;
 146   ptrace (step ? PT_STEP : PT_CONTINUE, inferior_pid, 1, signal, 0);
 147   if (errno)
 148     perror_with_name ("ptrace");
 149 }
 150
 151
 152 #if !defined (offsetof)
 153 #define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
 154 #endif
 155
 156 /* U_REGS_OFFSET is the offset of the registers within the u area.  */
 157 #if !defined (U_REGS_OFFSET)
 158 #define U_REGS_OFFSET \
 159   ptrace (PT_READ_U, inferior_pid, \
 160           (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
 161     - KERNEL_U_ADDR
 162 #endif
 163
 164 CORE_ADDR
 165 register_addr (regno, blockend)
 166      int regno;
 167      CORE_ADDR blockend;
 168 {
 169   CORE_ADDR addr;
 170
 171   if (regno < 0 || regno >= ARCH_NUM_REGS)
 172     error ("Invalid register number %d.", regno);
 173
 174   REGISTER_U_ADDR (addr, blockend, regno);
 175
 176   return addr;
 177 }
 178
 179 /* Fetch one register.  */
 180
 181 static void
 182 fetch_register (regno)
 183      int regno;
 184 {
 185   register unsigned int regaddr;
 186   char buf[MAX_REGISTER_RAW_SIZE];
 187   register int i;
 188
 189   /* Offset of registers within the u area.  */
 190   unsigned int offset;
 191
 192   offset = U_REGS_OFFSET;
 193
 194   regaddr = register_addr (regno, offset);
 195   for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
 196     {
 197       errno = 0;
 198       *(int *) &registers[ regno * 4 + i] = ptrace (PT_RUREGS, inferior_pid,
 199                                  (PTRACE_ARG3_TYPE) regaddr, 0, 0);
 200       regaddr += sizeof (int);
 201       if (errno != 0)
 202         {
 203           /* Warning, not error, in case we are attached; sometimes the
 204              kernel doesn't let us at the registers.  */
 205           char *err = strerror (errno);
 206           char *msg = alloca (strlen (err) + 128);
 207           sprintf (msg, "reading register %d: %s", regno, err);
 208           error (msg);
 209           goto error_exit;
 210         }
 211     }
 212  error_exit:;
 213 }
 214
 215 /* Fetch all registers, or just one, from the child process.  */
 216
 217 void
 218 fetch_inferior_registers (regno)
 219      int regno;
 220 {
 221   if (regno == -1 || regno == 0)
 222     for (regno = 0; regno < NUM_REGS; regno++)
 223       fetch_register (regno);
 224   else
 225     fetch_register (regno);
 226 }
 227
 228 /* Store our register values back into the inferior.
 229    If REGNO is -1, do this for all registers.
 230    Otherwise, REGNO specifies which register (so we can save time).  */
 231
 232 void
 233 store_inferior_registers (regno)
 234      int regno;
 235 {
 236   register unsigned int regaddr;
 237   char buf[80];
 238   extern char registers[];
 239   register int i;
 240   unsigned int offset = U_REGS_OFFSET;
 241   int scratch;
 242
 243   if (regno >= 0)
 244     {
 245       if (CANNOT_STORE_REGISTER (regno))
 246         return;
 247       regaddr = register_addr (regno, offset);
 248       errno = 0;
 249       if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM)
 250         {
 251           scratch = *(int *) &registers[REGISTER_BYTE (regno)] | 0x3;
 252           ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 253                   scratch, 0);
 254           if (errno != 0)
 255             {
 256               /* Error, even if attached.  Failing to write these two
 257                  registers is pretty serious.  */
 258               sprintf (buf, "writing register number %d", regno);
 259               perror_with_name (buf);
 260             }
 261         }
 262       else
 263         for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
 264           {
 265             errno = 0;
 266             ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 267                     *(int *) &registers[REGISTER_BYTE (regno) + i], 0);
 268             if (errno != 0)
 269               {
 270                 /* Warning, not error, in case we are attached; sometimes the
 271                    kernel doesn't let us at the registers.  */
 272                 char *err = strerror (errno);
 273                 char *msg = alloca (strlen (err) + 128);
 274                 sprintf (msg, "writing register %d: %s",
 275                          regno, err);
 276                 error (msg);
 277                 return;
 278               }
 279             regaddr += sizeof(int);
 280           }
 281     }
 282   else
 283     for (regno = 0; regno < NUM_REGS; regno++)
 284       store_inferior_registers (regno);
 285 }
 286
 287 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
 288    in the NEW_SUN_PTRACE case.
 289    It ought to be straightforward.  But it appears that writing did
 290    not write the data that I specified.  I cannot understand where
 291    it got the data that it actually did write.  */
 292
 293 /* Copy LEN bytes from inferior's memory starting at MEMADDR
 294    to debugger memory starting at MYADDR.  */
 295
 296 read_inferior_memory (memaddr, myaddr, len)
 297      CORE_ADDR memaddr;
 298      char *myaddr;
 299      int len;
 300 {
 301   register int i;
 302   /* Round starting address down to longword boundary.  */
 303   register CORE_ADDR addr = memaddr & -sizeof (int);
 304   /* Round ending address up; get number of longwords that makes.  */
 305   register int count
 306   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 307   /* Allocate buffer of that many longwords.  */
 308   register int *buffer = (int *) alloca (count * sizeof (int));
 309
 310   /* Read all the longwords */
 311   for (i = 0; i < count; i++, addr += sizeof (int))
 312     {
 313       buffer[i] = ptrace (1, inferior_pid, addr, 0, 0);
 314     }
 315
 316   /* Copy appropriate bytes out of the buffer.  */
 317   memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
 318 }
 319
 320 /* Copy LEN bytes of data from debugger memory at MYADDR
 321    to inferior's memory at MEMADDR.
 322    On failure (cannot write the inferior)
 323    returns the value of errno.  */
 324
 325 int
 326 write_inferior_memory (memaddr, myaddr, len)
 327      CORE_ADDR memaddr;
 328      char *myaddr;
 329      int len;
 330 {
 331   register int i;
 332   /* Round starting address down to longword boundary.  */
 333   register CORE_ADDR addr = memaddr & -sizeof (int);
 334   /* Round ending address up; get number of longwords that makes.  */
 335   register int count
 336   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 337   /* Allocate buffer of that many longwords.  */
 338   register int *buffer = (int *) alloca (count * sizeof (int));
 339   extern int errno;
 340
 341   /* Fill start and end extra bytes of buffer with existing memory data.  */
 342
 343   buffer[0] = ptrace (1, inferior_pid, addr, 0, 0);
 344
 345   if (count > 1)
 346     {
 347       buffer[count - 1]
 348         = ptrace (1, inferior_pid,
 349                   addr + (count - 1) * sizeof (int), 0, 0);
 350     }
 351
 352   /* Copy data to be written over corresponding part of buffer */
 353
 354   memcpy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
 355
 356   /* Write the entire buffer.  */
 357
 358   for (i = 0; i < count; i++, addr += sizeof (int))
 359     {
 360       errno = 0;
 361       ptrace (4, inferior_pid, addr, buffer[i], 0);
 362       if (errno)
 363         return errno;
 364     }
 365
 366   return 0;
 367 }
 368 \f
 369 void
 370 initialize ()
 371 {
 372   inferior_pid = 0;
 373 }
 374
 375 int
 376 have_inferior_p ()
 377 {
 378   return inferior_pid != 0;
 379 }