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 char registers[REGISTER_BYTES];
  38
  39 /* Index within `registers' of the first byte of the space for
  40    register N.  */
  41
  42
  43 char buf2[MAX_REGISTER_RAW_SIZE];
  44 /***************End MY defs*********************/
  45
  46 #include <sys/ptrace.h>
  47 #include <machine/reg.h>
  48
  49 extern char **environ;
  50 extern int errno;
  51 extern int inferior_pid;
  52 void quit (), perror_with_name ();
  53 int query ();
  54
  55 /* Start an inferior process and returns its pid.
  56    ALLARGS is a vector of program-name and args.
  57    ENV is the environment vector to pass.  */
  58
  59 int
  60 create_inferior (program, allargs)
  61      char *program;
  62      char **allargs;
  63 {
  64   int pid;
  65
  66   pid = fork ();
  67   if (pid < 0)
  68     perror_with_name ("fork");
  69
  70   if (pid == 0)
  71     {
  72       ptrace (PT_TRACE_ME, 0, 0, 0, 0);
  73
  74       execv (program, allargs);
  75
  76       fprintf (stderr, "Cannot exec %s: %s.\n", program,
  77                errno < sys_nerr ? sys_errlist[errno] : "unknown error");
  78       fflush (stderr);
  79       _exit (0177);
  80     }
  81
  82   return pid;
  83 }
  84
  85 /* Kill the inferior process.  Make us have no inferior.  */
  86
  87 void
  88 kill_inferior ()
  89 {
  90   if (inferior_pid == 0)
  91     return;
  92   ptrace (8, inferior_pid, 0, 0, 0);
  93   wait (0);
  94 /*************inferior_died ();****VK**************/
  95 }
  96
  97 /* Return nonzero if the given thread is still alive.  */
  98 int
  99 mythread_alive (pid)
 100      int pid;
 101 {
 102   return 1;
 103 }
 104
 105 /* Wait for process, returns status */
 106
 107 unsigned char
 108 mywait (status)
 109      char *status;
 110 {
 111   int pid;
 112   union wait w;
 113
 114   pid = wait (&w);
 115   if (pid != inferior_pid)
 116     perror_with_name ("wait");
 117
 118   if (WIFEXITED (w))
 119     {
 120       fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
 121       *status = 'W';
 122       return ((unsigned char) WEXITSTATUS (w));
 123     }
 124   else if (!WIFSTOPPED (w))
 125     {
 126       fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
 127       *status = 'X';
 128       return ((unsigned char) WTERMSIG (w));
 129     }
 130
 131   fetch_inferior_registers (0);
 132
 133   *status = 'T';
 134   return ((unsigned char) WSTOPSIG (w));
 135 }
 136
 137 /* Resume execution of the inferior process.
 138    If STEP is nonzero, single-step it.
 139    If SIGNAL is nonzero, give it that signal.  */
 140
 141 void
 142 myresume (step, signal)
 143      int step;
 144      int signal;
 145 {
 146   errno = 0;
 147   ptrace (step ? PT_STEP : PT_CONTINUE, inferior_pid, 1, signal, 0);
 148   if (errno)
 149     perror_with_name ("ptrace");
 150 }
 151
 152
 153 #if !defined (offsetof)
 154 #define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
 155 #endif
 156
 157 /* U_REGS_OFFSET is the offset of the registers within the u area.  */
 158 #if !defined (U_REGS_OFFSET)
 159 #define U_REGS_OFFSET \
 160   ptrace (PT_READ_U, inferior_pid, \
 161           (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
 162     - KERNEL_U_ADDR
 163 #endif
 164
 165 CORE_ADDR
 166 register_addr (regno, blockend)
 167      int regno;
 168      CORE_ADDR blockend;
 169 {
 170   CORE_ADDR addr;
 171
 172   if (regno < 0 || regno >= ARCH_NUM_REGS)
 173     error ("Invalid register number %d.", regno);
 174
 175   REGISTER_U_ADDR (addr, blockend, regno);
 176
 177   return addr;
 178 }
 179
 180 /* Fetch one register.  */
 181
 182 static void
 183 fetch_register (regno)
 184      int regno;
 185 {
 186   register unsigned int regaddr;
 187   char buf[MAX_REGISTER_RAW_SIZE];
 188   register int i;
 189
 190   /* Offset of registers within the u area.  */
 191   unsigned int offset;
 192
 193   offset = U_REGS_OFFSET;
 194
 195   regaddr = register_addr (regno, offset);
 196   for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
 197     {
 198       errno = 0;
 199       *(int *) &registers[regno * 4 + i] = ptrace (PT_RUREGS, inferior_pid,
 200                                           (PTRACE_ARG3_TYPE) regaddr, 0, 0);
 201       regaddr += sizeof (int);
 202       if (errno != 0)
 203         {
 204           /* Warning, not error, in case we are attached; sometimes the
 205              kernel doesn't let us at the registers.  */
 206           char *err = strerror (errno);
 207           char *msg = alloca (strlen (err) + 128);
 208           sprintf (msg, "reading register %d: %s", regno, err);
 209           error (msg);
 210           goto error_exit;
 211         }
 212     }
 213 error_exit:;
 214 }
 215
 216 /* Fetch all registers, or just one, from the child process.  */
 217
 218 void
 219 fetch_inferior_registers (regno)
 220      int regno;
 221 {
 222   if (regno == -1 || regno == 0)
 223     for (regno = 0; regno < NUM_REGS; regno++)
 224       fetch_register (regno);
 225   else
 226     fetch_register (regno);
 227 }
 228
 229 /* Store our register values back into the inferior.
 230    If REGNO is -1, do this for all registers.
 231    Otherwise, REGNO specifies which register (so we can save time).  */
 232
 233 void
 234 store_inferior_registers (regno)
 235      int regno;
 236 {
 237   register unsigned int regaddr;
 238   char buf[80];
 239   extern char registers[];
 240   register int i;
 241   unsigned int offset = U_REGS_OFFSET;
 242   int scratch;
 243
 244   if (regno >= 0)
 245     {
 246       if (CANNOT_STORE_REGISTER (regno))
 247         return;
 248       regaddr = register_addr (regno, offset);
 249       errno = 0;
 250       if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM)
 251         {
 252           scratch = *(int *) &registers[REGISTER_BYTE (regno)] | 0x3;
 253           ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 254                   scratch, 0);
 255           if (errno != 0)
 256             {
 257               /* Error, even if attached.  Failing to write these two
 258                  registers is pretty serious.  */
 259               sprintf (buf, "writing register number %d", regno);
 260               perror_with_name (buf);
 261             }
 262         }
 263       else
 264         for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
 265           {
 266             errno = 0;
 267             ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 268                     *(int *) &registers[REGISTER_BYTE (regno) + i], 0);
 269             if (errno != 0)
 270               {
 271                 /* Warning, not error, in case we are attached; sometimes the
 272                    kernel doesn't let us at the registers.  */
 273                 char *err = strerror (errno);
 274                 char *msg = alloca (strlen (err) + 128);
 275                 sprintf (msg, "writing register %d: %s",
 276                          regno, err);
 277                 error (msg);
 278                 return;
 279               }
 280             regaddr += sizeof (int);
 281           }
 282     }
 283   else
 284     for (regno = 0; regno < NUM_REGS; regno++)
 285       store_inferior_registers (regno);
 286 }
 287
 288 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
 289    in the NEW_SUN_PTRACE case.
 290    It ought to be straightforward.  But it appears that writing did
 291    not write the data that I specified.  I cannot understand where
 292    it got the data that it actually did write.  */
 293
 294 /* Copy LEN bytes from inferior's memory starting at MEMADDR
 295    to debugger memory starting at MYADDR.  */
 296
 297 read_inferior_memory (memaddr, myaddr, len)
 298      CORE_ADDR memaddr;
 299      char *myaddr;
 300      int len;
 301 {
 302   register int i;
 303   /* Round starting address down to longword boundary.  */
 304   register CORE_ADDR addr = memaddr & -sizeof (int);
 305   /* Round ending address up; get number of longwords that makes.  */
 306   register int count
 307   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 308   /* Allocate buffer of that many longwords.  */
 309   register int *buffer = (int *) alloca (count * sizeof (int));
 310
 311   /* Read all the longwords */
 312   for (i = 0; i < count; i++, addr += sizeof (int))
 313     {
 314       buffer[i] = ptrace (1, inferior_pid, addr, 0, 0);
 315     }
 316
 317   /* Copy appropriate bytes out of the buffer.  */
 318   memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
 319 }
 320
 321 /* Copy LEN bytes of data from debugger memory at MYADDR
 322    to inferior's memory at MEMADDR.
 323    On failure (cannot write the inferior)
 324    returns the value of errno.  */
 325
 326 int
 327 write_inferior_memory (memaddr, myaddr, len)
 328      CORE_ADDR memaddr;
 329      char *myaddr;
 330      int len;
 331 {
 332   register int i;
 333   /* Round starting address down to longword boundary.  */
 334   register CORE_ADDR addr = memaddr & -sizeof (int);
 335   /* Round ending address up; get number of longwords that makes.  */
 336   register int count
 337   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 338   /* Allocate buffer of that many longwords.  */
 339   register int *buffer = (int *) alloca (count * sizeof (int));
 340   extern int errno;
 341
 342   /* Fill start and end extra bytes of buffer with existing memory data.  */
 343
 344   buffer[0] = ptrace (1, inferior_pid, addr, 0, 0);
 345
 346   if (count > 1)
 347     {
 348       buffer[count - 1]
 349         = ptrace (1, inferior_pid,
 350                   addr + (count - 1) * sizeof (int), 0, 0);
 351     }
 352
 353   /* Copy data to be written over corresponding part of buffer */
 354
 355   memcpy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
 356
 357   /* Write the entire buffer.  */
 358
 359   for (i = 0; i < count; i++, addr += sizeof (int))
 360     {
 361       errno = 0;
 362       ptrace (4, inferior_pid, addr, buffer[i], 0);
 363       if (errno)
 364         return errno;
 365     }
 366
 367   return 0;
 368 }
 369 \f
 370 void
 371 initialize ()
 372 {
 373   inferior_pid = 0;
 374 }
 375
 376 int
 377 have_inferior_p ()
 378 {
 379   return inferior_pid != 0;
 380 }