gdb/gdbserver/low-sun3.c

   1 /* Low level interface to ptrace, for the remote server for GDB.
   2    Copyright (C) 1986, 1987, 1993 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., 675 Mass Ave, Cambridge, MA 02139, 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 int sys_nerr;
  49 extern char **sys_errlist;
  50 extern char **environ;
  51 extern int errno;
  52 extern int inferior_pid;
  53 void error (), 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 (PTRACE_TRACEME);
  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);
  94   wait (0);
  95   /*************inferior_died ();****VK**************/
  96 }
  97
  98 /* Wait for process, returns status */
  99
 100 unsigned char
 101 mywait (status)
 102      char *status;
 103 {
 104   int pid;
 105   union wait w;
 106
 107   pid = wait (&w);
 108   if (pid != inferior_pid)
 109     perror_with_name ("wait");
 110
 111   if (WIFEXITED (w))
 112     {
 113       fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
 114       *status = 'W';
 115       return ((unsigned char) WEXITSTATUS (w));
 116     }
 117   else if (!WIFSTOPPED (w))
 118     {
 119       fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
 120       *status = 'X';
 121       return ((unsigned char) WTERMSIG (w));
 122     }
 123
 124   fetch_inferior_registers (0);
 125
 126   *status = 'T';
 127   return ((unsigned char) WSTOPSIG (w));
 128 }
 129
 130 /* Resume execution of the inferior process.
 131    If STEP is nonzero, single-step it.
 132    If SIGNAL is nonzero, give it that signal.  */
 133
 134 void
 135 myresume (step, signal)
 136      int step;
 137      int signal;
 138 {
 139   errno = 0;
 140   ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, inferior_pid, 1, signal);
 141   if (errno)
 142     perror_with_name ("ptrace");
 143 }
 144
 145 /* Fetch one or more registers from the inferior.  REGNO == -1 to get
 146    them all.  We actually fetch more than requested, when convenient,
 147    marking them as valid so we won't fetch them again.  */
 148
 149 void
 150 fetch_inferior_registers (ignored)
 151      int ignored;
 152 {
 153   struct regs inferior_registers;
 154   struct fp_status inferior_fp_registers;
 155
 156   ptrace (PTRACE_GETREGS, inferior_pid,
 157           (PTRACE_ARG3_TYPE) &inferior_registers);
 158 #ifdef FP0_REGNUM
 159   ptrace (PTRACE_GETFPREGS, inferior_pid,
 160           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 161 #endif
 162
 163   memcpy (registers, &inferior_registers, 16 * 4);
 164 #ifdef FP0_REGNUM
 165   memcpy (&registers[REGISTER_BYTE (FP0_REGNUM)], &inferior_fp_registers,
 166           sizeof inferior_fp_registers.fps_regs);
 167 #endif
 168   *(int *)&registers[REGISTER_BYTE (PS_REGNUM)] = inferior_registers.r_ps;
 169   *(int *)&registers[REGISTER_BYTE (PC_REGNUM)] = inferior_registers.r_pc;
 170 #ifdef FP0_REGNUM
 171   memcpy
 172     (&registers[REGISTER_BYTE (FPC_REGNUM)],
 173      &inferior_fp_registers.fps_control,
 174      sizeof inferior_fp_registers - sizeof inferior_fp_registers.fps_regs);
 175 #endif
 176 }
 177
 178 /* Store our register values back into the inferior.
 179    If REGNO is -1, do this for all registers.
 180    Otherwise, REGNO specifies which register (so we can save time).  */
 181
 182 void
 183 store_inferior_registers (ignored)
 184      int ignored;
 185 {
 186   struct regs inferior_registers;
 187   struct fp_status inferior_fp_registers;
 188
 189   memcpy (&inferior_registers, registers, 16 * 4);
 190 #ifdef FP0_REGNUM
 191   memcpy (&inferior_fp_registers,
 192           &registers[REGISTER_BYTE (FP0_REGNUM)],
 193           sizeof inferior_fp_registers.fps_regs);
 194 #endif
 195   inferior_registers.r_ps = *(int *)&registers[REGISTER_BYTE (PS_REGNUM)];
 196   inferior_registers.r_pc = *(int *)&registers[REGISTER_BYTE (PC_REGNUM)];
 197
 198 #ifdef FP0_REGNUM
 199   memcpy (&inferior_fp_registers.fps_control,
 200           &registers[REGISTER_BYTE (FPC_REGNUM)],
 201           (sizeof inferior_fp_registers
 202            - sizeof inferior_fp_registers.fps_regs));
 203 #endif
 204
 205   ptrace (PTRACE_SETREGS, inferior_pid,
 206           (PTRACE_ARG3_TYPE) &inferior_registers);
 207 #if FP0_REGNUM
 208   ptrace (PTRACE_SETFPREGS, inferior_pid,
 209           (PTRACE_ARG3_TYPE) &inferior_fp_registers);
 210 #endif
 211 }
 212
 213 /* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
 214    in the NEW_SUN_PTRACE case.
 215    It ought to be straightforward.  But it appears that writing did
 216    not write the data that I specified.  I cannot understand where
 217    it got the data that it actually did write.  */
 218
 219 /* Copy LEN bytes from inferior's memory starting at MEMADDR
 220    to debugger memory starting at MYADDR.  */
 221
 222 read_inferior_memory (memaddr, myaddr, len)
 223      CORE_ADDR memaddr;
 224      char *myaddr;
 225      int len;
 226 {
 227   register int i;
 228   /* Round starting address down to longword boundary.  */
 229   register CORE_ADDR addr = memaddr & -sizeof (int);
 230   /* Round ending address up; get number of longwords that makes.  */
 231   register int count
 232   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 233   /* Allocate buffer of that many longwords.  */
 234   register int *buffer = (int *) alloca (count * sizeof (int));
 235
 236   /* Read all the longwords */
 237   for (i = 0; i < count; i++, addr += sizeof (int))
 238     {
 239       buffer[i] = ptrace (1, inferior_pid, addr, 0);
 240     }
 241
 242   /* Copy appropriate bytes out of the buffer.  */
 243   memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
 244 }
 245
 246 /* Copy LEN bytes of data from debugger memory at MYADDR
 247    to inferior's memory at MEMADDR.
 248    On failure (cannot write the inferior)
 249    returns the value of errno.  */
 250
 251 int
 252 write_inferior_memory (memaddr, myaddr, len)
 253      CORE_ADDR memaddr;
 254      char *myaddr;
 255      int len;
 256 {
 257   register int i;
 258   /* Round starting address down to longword boundary.  */
 259   register CORE_ADDR addr = memaddr & -sizeof (int);
 260   /* Round ending address up; get number of longwords that makes.  */
 261   register int count
 262   = (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
 263   /* Allocate buffer of that many longwords.  */
 264   register int *buffer = (int *) alloca (count * sizeof (int));
 265   extern int errno;
 266
 267   /* Fill start and end extra bytes of buffer with existing memory data.  */
 268
 269   buffer[0] = ptrace (1, inferior_pid, addr, 0);
 270
 271   if (count > 1)
 272     {
 273       buffer[count - 1]
 274         = ptrace (1, inferior_pid,
 275                   addr + (count - 1) * sizeof (int), 0);
 276     }
 277
 278   /* Copy data to be written over corresponding part of buffer */
 279
 280   memcpy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
 281
 282   /* Write the entire buffer.  */
 283
 284   for (i = 0; i < count; i++, addr += sizeof (int))
 285     {
 286       errno = 0;
 287       ptrace (4, inferior_pid, addr, buffer[i]);
 288       if (errno)
 289         return errno;
 290     }
 291
 292   return 0;
 293 }
 294 \f
 295 void
 296 initialize ()
 297 {
 298   inferior_pid = 0;
 299 }
 300
 301 int
 302 have_inferior_p ()
 303 {
 304   return inferior_pid != 0;
 305 }