/* Low level interface to ptrace, for the remote server for GDB.
Copyright (C) 1995, 1996 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "defs.h"
#include <sys/wait.h>
#include "frame.h"
#include "inferior.h"
#include <stdio.h>
#include <sys/param.h>
#include <sys/dir.h>
#include <sys/user.h>
#include <signal.h>
#include <sys/ioctl.h>
#if 0
#include <sgtty.h>
#endif
#include <fcntl.h>
/***************Begin MY defs*********************/
int quit_flag = 0;
char registers[REGISTER_BYTES];
/* Index within `registers' of the first byte of the space for
register N. */
char buf2[MAX_REGISTER_RAW_SIZE];
/***************End MY defs*********************/
#include <sys/ptrace.h>
#if 0
#include <machine/reg.h>
#endif
extern char **environ;
extern int errno;
extern int inferior_pid;
void quit (), perror_with_name ();
int query ();
/* Start an inferior process and returns its pid.
ALLARGS is a vector of program-name and args.
ENV is the environment vector to pass. */
int
create_inferior (program, allargs)
char *program;
char **allargs;
{
int pid;
pid = fork ();
if (pid < 0)
perror_with_name ("fork");
if (pid == 0)
{
ptrace (PTRACE_TRACEME, 0, 0, 0);
execv (program, allargs);
fprintf (stderr, "Cannot exec %s: %s.\n", program,
errno < sys_nerr ? sys_errlist[errno] : "unknown error");
fflush (stderr);
_exit (0177);
}
return pid;
}
/* Kill the inferior process. Make us have no inferior. */
void
kill_inferior ()
{
if (inferior_pid == 0)
return;
ptrace (PTRACE_KILL, inferior_pid, 0, 0);
wait (0);
/*************inferior_died ();****VK**************/
}
/* Return nonzero if the given thread is still alive. */
int
mythread_alive (pid)
int pid;
{
return 1;
}
/* Wait for process, returns status */
unsigned char
mywait (status)
char *status;
{
int pid;
union wait w;
pid = wait (&w);
if (pid != inferior_pid)
perror_with_name ("wait");
if (WIFEXITED (w))
{
fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
*status = 'W';
return ((unsigned char) WEXITSTATUS (w));
}
else if (!WIFSTOPPED (w))
{
fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
*status = 'X';
return ((unsigned char) WTERMSIG (w));
}
fetch_inferior_registers (0);
*status = 'T';
return ((unsigned char) WSTOPSIG (w));
}
/* Resume execution of the inferior process.
If STEP is nonzero, single-step it.
If SIGNAL is nonzero, give it that signal. */
void
myresume (step, signal)
int step;
int signal;
{
errno = 0;
ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, inferior_pid, 1, signal);
if (errno)
perror_with_name ("ptrace");
}
#if !defined (offsetof)
#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
#endif
/* U_REGS_OFFSET is the offset of the registers within the u area. */
#if !defined (U_REGS_OFFSET)
#define U_REGS_OFFSET \
ptrace (PT_READ_U, inferior_pid, \
(PTRACE_ARG3_TYPE) (offsetof (struct user, u_ar0)), 0) \
- KERNEL_U_ADDR
#endif
/* this table must line up with REGISTER_NAMES in tm-i386v.h */
/* symbols like 'EAX' come from <sys/reg.h> */
static int regmap[] =
{
EAX, ECX, EDX, EBX,
UESP, EBP, ESI, EDI,
EIP, EFL, CS, SS,
DS, ES, FS, GS,
};
int
i386_register_u_addr (blockend, regnum)
int blockend;
int regnum;
{
#if 0
/* this will be needed if fp registers are reinstated */
/* for now, you can look at them with 'info float'
* sys5 wont let you change them with ptrace anyway
*/
if (regnum >= FP0_REGNUM && regnum <= FP7_REGNUM)
{
int ubase, fpstate;
struct user u;
ubase = blockend + 4 * (SS + 1) - KSTKSZ;
fpstate = ubase + ((char *)&u.u_fpstate - (char *)&u);
return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM));
}
else
#endif
return (blockend + 4 * regmap[regnum]);
}
unsigned int
register_addr (regno, blockend)
int regno;
int blockend;
{
int addr;
if (regno < 0 || regno >= ARCH_NUM_REGS)
error ("Invalid register number %d.", regno);
REGISTER_U_ADDR (addr, blockend, regno);
return addr;
}
/* Fetch one register. */
static void
fetch_register (regno)
int regno;
{
register unsigned int regaddr;
char buf[MAX_REGISTER_RAW_SIZE];
register int i;
/* Offset of registers within the u area. */
unsigned int offset;
offset = U_REGS_OFFSET;
regaddr = register_addr (regno, offset);
for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
{
errno = 0;
*(int *) ®isters[ regno * 4 + i] = ptrace (PTRACE_PEEKUSR, inferior_pid,
(PTRACE_ARG3_TYPE) regaddr, 0);
regaddr += sizeof (int);
if (errno != 0)
{
/* Warning, not error, in case we are attached; sometimes the
kernel doesn't let us at the registers. */
char *err = strerror (errno);
char *msg = alloca (strlen (err) + 128);
sprintf (msg, "reading register %d: %s", regno, err);
error (msg);
goto error_exit;
}
}
error_exit:;
}
/* Fetch all registers, or just one, from the child process. */
void
fetch_inferior_registers (regno)
int regno;
{
if (regno == -1 || regno == 0)
for (regno = 0; regno < NUM_REGS-NUM_FREGS; regno++)
fetch_register (regno);
else
fetch_register (regno);
}
/* Store our register values back into the inferior.
If REGNO is -1, do this for all registers.
Otherwise, REGNO specifies which register (so we can save time). */
void
store_inferior_registers (regno)
int regno;
{
register unsigned int regaddr;
char buf[80];
register int i;
unsigned int offset = U_REGS_OFFSET;
int scratch;
if (regno >= 0)
{
#if 0
if (CANNOT_STORE_REGISTER (regno))
return;
#endif
regaddr = register_addr (regno, offset);
errno = 0;
#if 0
if (regno == PCOQ_HEAD_REGNUM || regno == PCOQ_TAIL_REGNUM)
{
scratch = *(int *) ®isters[REGISTER_BYTE (regno)] | 0x3;
ptrace (PT_WUREGS, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
scratch, 0);
if (errno != 0)
{
/* Error, even if attached. Failing to write these two
registers is pretty serious. */
sprintf (buf, "writing register number %d", regno);
perror_with_name (buf);
}
}
else
#endif
for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
{
errno = 0;
ptrace (PTRACE_POKEUSR, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
*(int *) ®isters[REGISTER_BYTE (regno) + i]);
if (errno != 0)
{
/* Warning, not error, in case we are attached; sometimes the
kernel doesn't let us at the registers. */
char *err = strerror (errno);
char *msg = alloca (strlen (err) + 128);
sprintf (msg, "writing register %d: %s",
regno, err);
error (msg);
return;
}
regaddr += sizeof(int);
}
}
else
for (regno = 0; regno < NUM_REGS-NUM_FREGS; regno++)
store_inferior_registers (regno);
}
/* NOTE! I tried using PTRACE_READDATA, etc., to read and write memory
in the NEW_SUN_PTRACE case.
It ought to be straightforward. But it appears that writing did
not write the data that I specified. I cannot understand where
it got the data that it actually did write. */
/* Copy LEN bytes from inferior's memory starting at MEMADDR
to debugger memory starting at MYADDR. */
read_inferior_memory (memaddr, myaddr, len)
CORE_ADDR memaddr;
char *myaddr;
int len;
{
register int i;
/* Round starting address down to longword boundary. */
register CORE_ADDR addr = memaddr & -sizeof (int);
/* Round ending address up; get number of longwords that makes. */
register int count
= (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
/* Allocate buffer of that many longwords. */
register int *buffer = (int *) alloca (count * sizeof (int));
/* Read all the longwords */
for (i = 0; i < count; i++, addr += sizeof (int))
{
buffer[i] = ptrace (PTRACE_PEEKTEXT, inferior_pid, addr, 0);
}
/* Copy appropriate bytes out of the buffer. */
memcpy (myaddr, (char *) buffer + (memaddr & (sizeof (int) - 1)), len);
}
/* Copy LEN bytes of data from debugger memory at MYADDR
to inferior's memory at MEMADDR.
On failure (cannot write the inferior)
returns the value of errno. */
int
write_inferior_memory (memaddr, myaddr, len)
CORE_ADDR memaddr;
char *myaddr;
int len;
{
register int i;
/* Round starting address down to longword boundary. */
register CORE_ADDR addr = memaddr & -sizeof (int);
/* Round ending address up; get number of longwords that makes. */
register int count
= (((memaddr + len) - addr) + sizeof (int) - 1) / sizeof (int);
/* Allocate buffer of that many longwords. */
register int *buffer = (int *) alloca (count * sizeof (int));
extern int errno;
/* Fill start and end extra bytes of buffer with existing memory data. */
buffer[0] = ptrace (PTRACE_PEEKTEXT, inferior_pid, addr, 0);
if (count > 1)
{
buffer[count - 1]
= ptrace (PTRACE_PEEKTEXT, inferior_pid,
addr + (count - 1) * sizeof (int), 0);
}
/* Copy data to be written over corresponding part of buffer */
memcpy ((char *) buffer + (memaddr & (sizeof (int) - 1)), myaddr, len);
/* Write the entire buffer. */
for (i = 0; i < count; i++, addr += sizeof (int))
{
errno = 0;
ptrace (PTRACE_POKETEXT, inferior_pid, addr, buffer[i]);
if (errno)
return errno;
}
return 0;
}
void
initialize ()
{
inferior_pid = 0;
}
int
have_inferior_p ()
{
return inferior_pid != 0;
}