binutils-gdb/gdb/i386lynx-nat.c

284 lines
6.9 KiB
C

/* Native-dependent code for Lynx running on i386's, for GDB.
Copyright 1988, 1989, 1991, 1992, 1993
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., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "defs.h"
#include "frame.h"
#include "inferior.h"
#include "target.h"
#include <sys/ptrace.h>
#include "/usr/include/sys/wait.h"
/* these values indicate the offset of the named register in the econtext
structure */
#define EAX 10
#define ECX 9
#define EDX 8
#define EBX 7
#define ESP 16
#define EBP 5
#define ESI 4
#define EDI 3
#define EIP 13
#define EFL 15
#define CS 14
#define SS 17
#define DS 2
#define ES 1
/* Currently these are not being used. So set them to 0 */
#define FS 0
#define GS 0
/* this table must line up with REGISTER_NAMES in m-i386.h */
static unsigned int regmap[] =
{
EAX, ECX, EDX, EBX,
ESP, EBP, ESI, EDI,
EIP, EFL, CS, SS,
DS, ES, FS, GS,
};
/* Return the address in the core dump or inferior of register REGNO.
BLOCKEND is the address of the econtext structure */
static unsigned int
register_addr (regno, blockend)
int regno, blockend;
{
if (regno < 0 || regno >= NUM_REGS)
error ("Invalid register number %d.", regno);
return (blockend + regmap[regno] * sizeof (long));
}
/* Fetch one register. */
static void
fetch_register (regno, offset, bpid)
int regno, bpid;
unsigned int offset;
{
unsigned int regaddr;
char buf[MAX_REGISTER_RAW_SIZE];
char mess[128]; /* For messages */
int i;
regaddr = register_addr (regno, offset);
for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof (int))
{
errno = 0;
*(int *) &buf[i] = ptrace (PTRACE_PEEKTHREAD, bpid,
(PTRACE_ARG3_TYPE) regaddr, 0);
regaddr += sizeof (int);
if (errno != 0)
{
sprintf (mess, "reading register %s (#%d)", reg_names[regno], regno);
perror_with_name (mess);
}
}
supply_register (regno, buf);
}
/* 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). */
static void
store_register (regno, offset, bpid)
int regno, bpid;
unsigned int offset;
{
unsigned int regaddr;
char mess[128];
extern char registers[];
int i;
regaddr = register_addr (regno, offset);
for (i = 0; i < REGISTER_RAW_SIZE (regno); i += sizeof(int))
{
errno = 0;
ptrace (PTRACE_POKEUSER, bpid, (PTRACE_ARG3_TYPE) regaddr,
*(int *) &registers[REGISTER_BYTE (regno) + i]);
if (errno != 0)
{
sprintf (mess, "writing register number %d(%d)", regno, i);
perror_with_name (mess);
}
regaddr += sizeof(int);
}
}
/* return an offset for use with register_addr() */
static unsigned int
fetch_offset (pid)
int pid;
{
struct st_entry s;
unsigned int specpage_off, offset = (char *) &s.ecp - (char *) &s;
errno = 0;
specpage_off = ptrace (PTRACE_THREADUSER, pid, (PTRACE_ARG3_TYPE) 0, 0);
if (errno != 0)
perror_with_name ("ptrace");
errno = 0;
offset = ptrace (PTRACE_PEEKTHREAD, pid, (PTRACE_ARG3_TYPE) offset, 0)
- specpage_off;
if (errno != 0)
perror_with_name ("ptrace");
return offset;
}
/* Fetch all registers, or just one, from the child process. */
void
fetch_inferior_registers (regno)
int regno;
{
unsigned int offset = fetch_offset (inferior_pid);
if (regno == -1)
{
for (regno = 0; regno < NUM_REGS; regno++)
fetch_register (regno, offset, inferior_pid);
}
else
fetch_register (regno, offset, inferior_pid);
}
/* Store all registers, or just one, to the child process. */
void
store_inferior_registers (regno)
int regno;
{
unsigned int offset = fetch_offset (inferior_pid);
if (regno == -1)
{
for (regno = 0; regno < NUM_REGS; regno++)
store_register (regno, offset, inferior_pid);
}
else
store_register (regno, offset, inferior_pid);
}
/* Wait for child to do something. Return pid of child, or -1 in case
of error; store status through argument pointer STATUS. */
int
child_wait (pid, status)
int pid;
int *status;
{
int save_errno;
int thread;
while (1)
{
int sig;
if (attach_flag)
set_sigint_trap(); /* Causes SIGINT to be passed on to the
attached process. */
pid = wait (status);
save_errno = errno;
if (attach_flag)
clear_sigint_trap();
if (pid == -1)
{
if (save_errno == EINTR)
continue;
fprintf (stderr, "Child process unexpectedly missing: %s.\n",
safe_strerror (save_errno));
*status = 42; /* Claim it exited with signal 42 */
return -1;
}
if (pid != PIDGET (inferior_pid)) /* Some other process?!? */
continue;
/* thread = WIFTID (*status);*/
thread = *status >> 16;
/* Initial thread value can only be acquired via wait, so we have to
resort to this hack. */
if (TIDGET (inferior_pid) == 0)
{
inferior_pid = BUILDPID (inferior_pid, thread);
add_thread (inferior_pid);
}
pid = BUILDPID (pid, thread);
return pid;
}
}
/* Convert a Lynx process ID to a string. Returns the string in a static
buffer. */
char *
i386lynx_pid_to_str (pid)
int pid;
{
static char buf[40];
sprintf (buf, "process %d thread %d", PIDGET (pid), TIDGET (pid));
return buf;
}
/* Extract the register values out of the core file and store
them where `read_register' will find them.
CORE_REG_SECT points to the register values themselves, read into memory.
CORE_REG_SIZE is the size of that area.
WHICH says which set of registers we are handling (0 = int, 2 = float
on machines where they are discontiguous).
REG_ADDR is the offset from u.u_ar0 to the register values relative to
core_reg_sect. This is used with old-fashioned core files to
locate the registers in a large upage-plus-stack ".reg" section.
Original upage address X is at location core_reg_sect+x+reg_addr.
*/
void
fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
char *core_reg_sect;
unsigned core_reg_size;
int which;
unsigned reg_addr;
{
struct st_entry s;
unsigned int regno, addr;
for (regno = 0; regno < NUM_REGS; regno++)
{
addr = register_addr (regno, (char *) &s.ec - (char *) &s);
supply_register (regno, core_reg_sect + addr);
}
}