gdb/gdbserver/low-hppabsd.c

   1 /* Low level interface to ptrace, for the remote server for GDB.
   2    Copyright 1995, 1996, 1999, 2000, 2001, 2002 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 "server.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 static char my_registers[REGISTER_BYTES];
  37 char *registers = my_registers;
  38 /***************End MY defs*********************/
  39
  40 #include <sys/ptrace.h>
  41 #include <machine/reg.h>
  42
  43 extern int errno;
  44
  45 /* Start an inferior process and returns its pid.
  46    ALLARGS is a vector of program-name and args. */
  47
  48 int
  49 create_inferior (char *program, char **allargs)
  50 {
  51   int pid;
  52
  53   pid = fork ();
  54   if (pid < 0)
  55     perror_with_name ("fork");
  56
  57   if (pid == 0)
  58     {
  59       ptrace (PT_TRACE_ME, 0, 0, 0, 0);
  60
  61       execv (program, allargs);
  62
  63       fprintf (stderr, "Cannot exec %s: %s.\n", program,
  64                errno < sys_nerr ? sys_errlist[errno] : "unknown error");
  65       fflush (stderr);
  66       _exit (0177);
  67     }
  68
  69   return pid;
  70 }
  71
  72 /* Kill the inferior process.  Make us have no inferior.  */
  73
  74 void
  75 kill_inferior (void)
  76 {
  77   if (inferior_pid == 0)
  78     return;
  79   ptrace (8, inferior_pid, 0, 0, 0);
  80   wait (0);
  81 /*************inferior_died ();****VK**************/
  82 }
  83
  84 /* Attaching is not supported.  */
  85 int
  86 myattach (int pid)
  87 {
  88   return -1;
  89 }
  90
  91 /* Return nonzero if the given thread is still alive.  */
  92 int
  93 mythread_alive (int pid)
  94 {
  95   return 1;
  96 }
  97
  98 /* Wait for process, returns status */
  99
 100 unsigned char
 101 mywait (char *status)
 102 {
 103   int pid;
 104   union wait w;
 105
 106   enable_async_io ();
 107   pid = waitpid (inferior_pid, &w, 0);
 108   disable_async_io ();
 109   if (pid != inferior_pid)
 110     perror_with_name ("wait");
 111
 112   if (WIFEXITED (w))
 113     {
 114       fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
 115       *status = 'W';
 116       return ((unsigned char) WEXITSTATUS (w));
 117     }
 118   else if (!WIFSTOPPED (w))
 119     {
 120       fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
 121       *status = 'X';
 122       return ((unsigned char) WTERMSIG (w));
 123     }
 124
 125   fetch_inferior_registers (0);
 126
 127   *status = 'T';
 128   return ((unsigned char) WSTOPSIG (w));
 129 }
 130
 131 /* Resume execution of the inferior process.
 132    If STEP is nonzero, single-step it.
 133    If SIGNAL is nonzero, give it that signal.  */
 134
 135 void
 136 myresume (int step, int signal)
 137 {
 138   errno = 0;
 139   ptrace (step ? PT_STEP : PT_CONTINUE, inferior_pid, 1, signal, 0);
 140   if (errno)
 141     perror_with_name ("ptrace");
 142 }
 143
 144
 145 #if !defined (offsetof)
 146 #define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
 147 #endif
 148
 149 /* U_REGS_OFFSET is the offset of the registers within the u area.  */
 150 #if !defined (U_REGS_OFFSET)
 151 #define U_REGS_OFFSET \
 152   ptrace (PT_READ_U, inferior_pid, \
 153           (PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
 154     - KERNEL_U_ADDR
 155 #endif
 156
 157 CORE_ADDR
 158 register_addr (int regno, CORE_ADDR blockend)
 159 {
 160   CORE_ADDR addr;
 161
 162   if (regno < 0 || regno >= NUM_REGS)
 163     error ("Invalid register number %d.", regno);
 164
 165   REGISTER_U_ADDR (addr, blockend, regno);
 166
 167   return addr;
 168 }
 169
 170 /* Fetch one register.  */
 171
 172 static void
 173 fetch_register (int regno)
 174 {
 175   register unsigned int regaddr;
 176   char buf[MAX_REGISTER_RAW_SIZE];
 177   register int i;
 178
 179   /* Offset of registers within the u area.  */
 180   unsigned int offset;
 181
 182   offset = U_REGS_OFFSET;
 183
 184   regaddr = register_addr (regno, offset);
 185   for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
 186     {
 187       errno = 0;
 188       *(int *) &registers[regno * 4 + i] = ptrace (PT_RUREGS, inferior_pid,
 189                                           (PTRACE_ARG3_TYPE) regaddr, 0, 0);
 190       regaddr += sizeof (int);
 191       if (errno != 0)
 192         {
 193           /* Warning, not error, in case we are attached; sometimes the
 194              kernel doesn't let us at the registers.  */
 195           char *err = strerror (errno);
 196           char *msg = alloca (strlen (err) + 128);
 197           sprintf (msg, "reading register %d: %s", regno, err);
 198           error (msg);
 199           goto error_exit;
 200         }
 201     }
 202 error_exit:;
 203 }
 204
 205 /* Fetch all registers, or just one, from the child process.  */
 206
 207 void
 208 fetch_inferior_registers (int regno)
 209 {
 210   if (regno == -1 || regno == 0)
 211     for (regno = 0; regno < NUM_REGS; regno++)
 212       fetch_register (regno);
 213   else
 214     fetch_register (regno);
 215 }
 216
 217 /* Store our register values back into the inferior.
 218    If REGNO is -1, do this for all registers.
 219    Otherwise, REGNO specifies which register (so we can save time).  */
 220
 221 void
 222 store_inferior_registers (int regno)
 223 {
 224   register unsigned int regaddr;
 225   char buf[80];
 226   extern char registers[];
 227   register int i;
 228   unsigned int offset = U_REGS_OFFSET;
 229   int scratch;
 230
 231   if (regno >= 0)
 232     {
 233       if (CANNOT_STORE_REGISTER (regno))
 234         return;
 235       regaddr = register_addr (regno, offset);
 236       errno = 0;
 237       if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM)
 238         {
 239           scratch = *(int *) &registers[REGISTER_BYTE (regno)] | 0x3;
 240           ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 241                   scratch, 0);
 242           if (errno != 0)
 243             {
 244               /* Error, even if attached.  Failing to write these two
 245                  registers is pretty serious.  */
 246               sprintf (buf, "writing register number %d", regno);
 247               perror_with_name (buf);
 248             }
 249         }
 250       else
 251         for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
 252           {
 253             errno = 0;
 254             ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
 255                     *(int *) &registers[REGISTER_BYTE (regno) + i], 0);
 256             if (errno != 0)
 257               {
 258                 /* Warning, not error, in case we are attached; sometimes the
 259                    kernel doesn't let us at the registers.  */
 260                 char *err = strerror (errno);
 261                 char *msg = alloca (strlen (err) + 128);
 262                 sprintf (msg, "writing register %d: %s",
 263                          regno, err);
 264                 error (msg);
 265                 return;
 266               }
 267             regaddr += sizeof (int);
 268           }
 269     }
 270   else
 271     for (regno = 0; regno < NUM_REGS; regno++)
 272       store_inferior_registers (regno);
 273 }
 274
 275 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
 276    in the NEW_SUN_PTRACE case.
 277    It ought to be straightforward.  But it appears that writing did
 278    not write the data that I specified.  I cannot understand where
 279    it got the data that it actually did write.  */
 280
 281 /* Copy LEN bytes from inferior's memory starting at MEMADDR
 282    to debugger memory starting at MYADDR.  */
 283
 284 void
 285 read_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
 286 {
 287   register int i;
 288   /* Round starting address down to longword boundary.  */
 289   register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (int);
 290   /* Round ending address up; get number of longwords that makes.  */
 291   register int count
 292   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 293   /* Allocate buffer of that many longwords.  */
 294   register int *buffer = (int *) alloca (count * sizeof (int));
 295
 296   /* Read all the longwords */
 297   for (i = 0; i < count; i++, addr += sizeof (int))
 298     {
 299       buffer[i] = ptrace (1, inferior_pid, addr, 0, 0);
 300     }
 301
 302   /* Copy appropriate bytes out of the buffer.  */
 303   memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
 304 }
 305
 306 /* Copy LEN bytes of data from debugger memory at MYADDR
 307    to inferior's memory at MEMADDR.
 308    On failure (cannot write the inferior)
 309    returns the value of errno.  */
 310
 311 int
 312 write_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len)
 313 {
 314   register int i;
 315   /* Round starting address down to longword boundary.  */
 316   register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (int);
 317   /* Round ending address up; get number of longwords that makes.  */
 318   register int count
 319   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 320   /* Allocate buffer of that many longwords.  */
 321   register int *buffer = (int *) alloca (count * sizeof (int));
 322   extern int errno;
 323
 324   /* Fill start and end extra bytes of buffer with existing memory data.  */
 325
 326   buffer[0] = ptrace (1, inferior_pid, addr, 0, 0);
 327
 328   if (count > 1)
 329     {
 330       buffer[count - 1]
 331         = ptrace (1, inferior_pid,
 332                   addr + (count - 1) * sizeof (int), 0, 0);
 333     }
 334
 335   /* Copy data to be written over corresponding part of buffer */
 336
 337   memcpy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
 338
 339   /* Write the entire buffer.  */
 340
 341   for (i = 0; i < count; i++, addr += sizeof (int))
 342     {
 343       errno = 0;
 344       ptrace (4, inferior_pid, addr, buffer[i], 0);
 345       if (errno)
 346         return errno;
 347     }
 348
 349   return 0;
 350 }
 351 \f
 352 void
 353 initialize_low (void)
 354 {
 355 }