1 /* Generic GNU/Linux target using traditional ptrace register access.
3 Copyright (C) 1988-2019 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "linux-nat-trad.h"
23 #include "nat/gdb_ptrace.h"
24 #include "inf-ptrace.h"
27 /* Fetch register REGNUM from the inferior. */
30 linux_nat_trad_target::fetch_register (struct regcache *regcache, int regnum)
32 struct gdbarch *gdbarch = regcache->arch ();
33 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
40 /* This isn't really an address, but ptrace thinks of it as one. */
41 addr = register_u_offset (gdbarch, regnum, 0);
42 if (addr == (CORE_ADDR)-1
43 || gdbarch_cannot_fetch_register (gdbarch, regnum))
45 regcache->raw_supply (regnum, NULL);
49 pid = get_ptrace_pid (regcache->ptid ());
51 size = register_size (gdbarch, regnum);
52 buf = (gdb_byte *) alloca (size);
54 /* Read the register contents from the inferior a chunk at a time. */
55 for (i = 0; i < size; i += sizeof (PTRACE_TYPE_RET))
57 size_t chunk = std::min (sizeof (PTRACE_TYPE_RET), size - i);
61 val = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3) (uintptr_t) addr, 0);
63 error (_("Couldn't read register %s (#%d): %s."),
64 gdbarch_register_name (gdbarch, regnum),
65 regnum, safe_strerror (errno));
66 store_unsigned_integer (buf + i, chunk, byte_order, val);
68 addr += sizeof (PTRACE_TYPE_RET);
70 regcache->raw_supply (regnum, buf);
73 /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this
77 linux_nat_trad_target::fetch_registers (struct regcache *regcache, int regnum)
81 regnum < gdbarch_num_regs (regcache->arch ());
83 fetch_register (regcache, regnum);
85 fetch_register (regcache, regnum);
88 /* Store register REGNUM into the inferior. */
91 linux_nat_trad_target::store_register (const struct regcache *regcache,
94 struct gdbarch *gdbarch = regcache->arch ();
95 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
102 /* This isn't really an address, but ptrace thinks of it as one. */
103 addr = register_u_offset (gdbarch, regnum, 1);
104 if (addr == (CORE_ADDR)-1
105 || gdbarch_cannot_store_register (gdbarch, regnum))
108 pid = get_ptrace_pid (regcache->ptid ());
110 size = register_size (gdbarch, regnum);
111 buf = (gdb_byte *) alloca (size);
113 /* Write the register contents into the inferior a chunk at a time. */
114 regcache->raw_collect (regnum, buf);
115 for (i = 0; i < size; i += sizeof (PTRACE_TYPE_RET))
117 size_t chunk = std::min (sizeof (PTRACE_TYPE_RET), size - i);
120 val = extract_unsigned_integer (buf + i, chunk, byte_order);
122 ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3) (uintptr_t) addr, val);
124 error (_("Couldn't write register %s (#%d): %s."),
125 gdbarch_register_name (gdbarch, regnum),
126 regnum, safe_strerror (errno));
128 addr += sizeof (PTRACE_TYPE_RET);
132 /* Store register REGNUM back into the inferior. If REGNUM is -1, do
133 this for all registers. */
136 linux_nat_trad_target::store_registers (struct regcache *regcache, int regnum)
140 regnum < gdbarch_num_regs (regcache->arch ());
142 store_register (regcache, regnum);
144 store_register (regcache, regnum);