blob: b2c982d997e32c750ed28d426457b99172b65e75 [file] [log] [blame]
/* Generic GNU/Linux target using traditional ptrace register access.
Copyright (C) 1988-2024 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 3 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, see <http://www.gnu.org/licenses/>. */
#include "linux-nat-trad.h"
#include "extract-store-integer.h"
#include "nat/gdb_ptrace.h"
#include "inf-ptrace.h"
#include "gdbarch.h"
/* Fetch register REGNUM from the inferior. */
void
linux_nat_trad_target::fetch_register (struct regcache *regcache, int regnum)
{
struct gdbarch *gdbarch = regcache->arch ();
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR addr;
gdb_byte *buf;
size_t size;
pid_t pid;
int i;
/* This isn't really an address, but ptrace thinks of it as one. */
addr = register_u_offset (gdbarch, regnum, 0);
if (addr == (CORE_ADDR)-1
|| gdbarch_cannot_fetch_register (gdbarch, regnum))
{
regcache->raw_supply (regnum, NULL);
return;
}
pid = get_ptrace_pid (regcache->ptid ());
size = register_size (gdbarch, regnum);
buf = (gdb_byte *) alloca (size);
/* Read the register contents from the inferior a chunk at a time. */
for (i = 0; i < size; i += sizeof (PTRACE_TYPE_RET))
{
size_t chunk = std::min (sizeof (PTRACE_TYPE_RET), size - i);
PTRACE_TYPE_RET val;
errno = 0;
val = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3) (uintptr_t) addr, 0);
if (errno != 0)
error (_("Couldn't read register %s (#%d): %s."),
gdbarch_register_name (gdbarch, regnum),
regnum, safe_strerror (errno));
store_unsigned_integer (buf + i, chunk, byte_order, val);
addr += sizeof (PTRACE_TYPE_RET);
}
regcache->raw_supply (regnum, buf);
}
/* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
for all registers. */
void
linux_nat_trad_target::fetch_registers (struct regcache *regcache, int regnum)
{
if (regnum == -1)
for (regnum = 0;
regnum < gdbarch_num_regs (regcache->arch ());
regnum++)
fetch_register (regcache, regnum);
else
fetch_register (regcache, regnum);
}
/* Store register REGNUM into the inferior. */
void
linux_nat_trad_target::store_register (const struct regcache *regcache,
int regnum)
{
struct gdbarch *gdbarch = regcache->arch ();
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR addr;
size_t size;
gdb_byte *buf;
pid_t pid;
int i;
/* This isn't really an address, but ptrace thinks of it as one. */
addr = register_u_offset (gdbarch, regnum, 1);
if (addr == (CORE_ADDR)-1
|| gdbarch_cannot_store_register (gdbarch, regnum))
return;
pid = get_ptrace_pid (regcache->ptid ());
size = register_size (gdbarch, regnum);
buf = (gdb_byte *) alloca (size);
/* Write the register contents into the inferior a chunk at a time. */
regcache->raw_collect (regnum, buf);
for (i = 0; i < size; i += sizeof (PTRACE_TYPE_RET))
{
size_t chunk = std::min (sizeof (PTRACE_TYPE_RET), size - i);
PTRACE_TYPE_RET val;
val = extract_unsigned_integer (buf + i, chunk, byte_order);
errno = 0;
ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3) (uintptr_t) addr, val);
if (errno != 0)
error (_("Couldn't write register %s (#%d): %s."),
gdbarch_register_name (gdbarch, regnum),
regnum, safe_strerror (errno));
addr += sizeof (PTRACE_TYPE_RET);
}
}
/* Store register REGNUM back into the inferior. If REGNUM is -1, do
this for all registers. */
void
linux_nat_trad_target::store_registers (struct regcache *regcache, int regnum)
{
if (regnum == -1)
for (regnum = 0;
regnum < gdbarch_num_regs (regcache->arch ());
regnum++)
store_register (regcache, regnum);
else
store_register (regcache, regnum);
}