| /* Native-dependent code for modern i386 BSD's. |
| |
| Copyright (C) 2000-2024 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 "inferior.h" |
| #include "regcache.h" |
| |
| #include <signal.h> |
| #include <sys/types.h> |
| #include <sys/ptrace.h> |
| #include <machine/reg.h> |
| #include <machine/frame.h> |
| |
| #include "i386-tdep.h" |
| #include "i387-tdep.h" |
| #include "x86-bsd-nat.h" |
| #include "i386-bsd-nat.h" |
| #include "inf-ptrace.h" |
| |
| |
| static PTRACE_TYPE_RET |
| gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr, |
| PTRACE_TYPE_ARG4 data) |
| { |
| #ifdef __NetBSD__ |
| gdb_assert (data == 0); |
| /* Support for NetBSD threads: unlike other ptrace implementations in this |
| file, NetBSD requires that we pass both the pid and lwp. */ |
| return ptrace (request, ptid.pid (), addr, ptid.lwp ()); |
| #else |
| pid_t pid = get_ptrace_pid (ptid); |
| return ptrace (request, pid, addr, data); |
| #endif |
| } |
| |
| /* In older BSD versions we cannot get at some of the segment |
| registers. FreeBSD for example didn't support the %fs and %gs |
| registers until the 3.0 release. We have autoconf checks for their |
| presence, and deal gracefully with their absence. */ |
| |
| /* Offset in `struct reg' where MEMBER is stored. */ |
| #define REG_OFFSET(member) offsetof (struct reg, member) |
| |
| /* At i386bsd_reg_offset[REGNUM] you'll find the offset in `struct |
| reg' where the GDB register REGNUM is stored. Unsupported |
| registers are marked with `-1'. */ |
| static int i386bsd_r_reg_offset[] = |
| { |
| REG_OFFSET (r_eax), |
| REG_OFFSET (r_ecx), |
| REG_OFFSET (r_edx), |
| REG_OFFSET (r_ebx), |
| REG_OFFSET (r_esp), |
| REG_OFFSET (r_ebp), |
| REG_OFFSET (r_esi), |
| REG_OFFSET (r_edi), |
| REG_OFFSET (r_eip), |
| REG_OFFSET (r_eflags), |
| REG_OFFSET (r_cs), |
| REG_OFFSET (r_ss), |
| REG_OFFSET (r_ds), |
| REG_OFFSET (r_es), |
| #ifdef HAVE_STRUCT_REG_R_FS |
| REG_OFFSET (r_fs), |
| #else |
| -1, |
| #endif |
| #ifdef HAVE_STRUCT_REG_R_GS |
| REG_OFFSET (r_gs) |
| #else |
| -1 |
| #endif |
| }; |
| |
| /* Macro to determine if a register is fetched with PT_GETREGS. */ |
| #define GETREGS_SUPPLIES(regnum) \ |
| ((0 <= (regnum) && (regnum) <= 15)) |
| |
| /* Set to 1 if the kernel supports PT_GETXMMREGS. Initialized to -1 |
| so that we try PT_GETXMMREGS the first time around. */ |
| static int have_ptrace_xmmregs = -1; |
| |
| |
| /* Supply the general-purpose registers in GREGS, to REGCACHE. */ |
| |
| static void |
| i386bsd_supply_gregset (struct regcache *regcache, const void *gregs) |
| { |
| const char *regs = (const char *) gregs; |
| int regnum; |
| |
| for (regnum = 0; regnum < ARRAY_SIZE (i386bsd_r_reg_offset); regnum++) |
| { |
| int offset = i386bsd_r_reg_offset[regnum]; |
| |
| if (offset != -1) |
| regcache->raw_supply (regnum, regs + offset); |
| } |
| } |
| |
| /* Collect register REGNUM from REGCACHE and store its contents in |
| GREGS. If REGNUM is -1, collect and store all appropriate |
| registers. */ |
| |
| static void |
| i386bsd_collect_gregset (const struct regcache *regcache, |
| void *gregs, int regnum) |
| { |
| char *regs = (char *) gregs; |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE (i386bsd_r_reg_offset); i++) |
| { |
| if (regnum == -1 || regnum == i) |
| { |
| int offset = i386bsd_r_reg_offset[i]; |
| |
| if (offset != -1) |
| regcache->raw_collect (i, regs + offset); |
| } |
| } |
| } |
| |
| /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this |
| for all registers (including the floating point registers). */ |
| |
| void |
| i386bsd_fetch_inferior_registers (struct regcache *regcache, int regnum) |
| { |
| ptid_t ptid = regcache->ptid (); |
| |
| if (regnum == -1 || GETREGS_SUPPLIES (regnum)) |
| { |
| struct reg regs; |
| |
| if (gdb_ptrace (PT_GETREGS, ptid, (PTRACE_TYPE_ARG3) ®s, 0) == -1) |
| perror_with_name (_("Couldn't get registers")); |
| |
| i386bsd_supply_gregset (regcache, ®s); |
| if (regnum != -1) |
| return; |
| } |
| |
| if (regnum == -1 || regnum >= I386_ST0_REGNUM) |
| { |
| struct fpreg fpregs; |
| char xmmregs[512]; |
| |
| if (have_ptrace_xmmregs != 0 |
| && gdb_ptrace(PT_GETXMMREGS, ptid, |
| (PTRACE_TYPE_ARG3) xmmregs, 0) == 0) |
| { |
| have_ptrace_xmmregs = 1; |
| i387_supply_fxsave (regcache, -1, xmmregs); |
| } |
| else |
| { |
| have_ptrace_xmmregs = 0; |
| if (gdb_ptrace (PT_GETFPREGS, ptid, |
| (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) |
| perror_with_name (_("Couldn't get floating point status")); |
| |
| i387_supply_fsave (regcache, -1, &fpregs); |
| } |
| } |
| } |
| |
| /* Store register REGNUM back into the inferior. If REGNUM is -1, do |
| this for all registers (including the floating point registers). */ |
| |
| void |
| i386bsd_store_inferior_registers (struct regcache *regcache, int regnum) |
| { |
| ptid_t ptid = regcache->ptid (); |
| |
| if (regnum == -1 || GETREGS_SUPPLIES (regnum)) |
| { |
| struct reg regs; |
| |
| if (gdb_ptrace (PT_GETREGS, ptid, (PTRACE_TYPE_ARG3) ®s, 0) == -1) |
| perror_with_name (_("Couldn't get registers")); |
| |
| i386bsd_collect_gregset (regcache, ®s, regnum); |
| |
| if (gdb_ptrace (PT_SETREGS, ptid, (PTRACE_TYPE_ARG3) ®s, 0) == -1) |
| perror_with_name (_("Couldn't write registers")); |
| |
| if (regnum != -1) |
| return; |
| } |
| |
| if (regnum == -1 || regnum >= I386_ST0_REGNUM) |
| { |
| struct fpreg fpregs; |
| char xmmregs[512]; |
| |
| if (have_ptrace_xmmregs != 0 |
| && gdb_ptrace(PT_GETXMMREGS, ptid, |
| (PTRACE_TYPE_ARG3) xmmregs, 0) == 0) |
| { |
| have_ptrace_xmmregs = 1; |
| |
| i387_collect_fxsave (regcache, regnum, xmmregs); |
| |
| if (gdb_ptrace (PT_SETXMMREGS, ptid, |
| (PTRACE_TYPE_ARG3) xmmregs, 0) == -1) |
| perror_with_name (_("Couldn't write XMM registers")); |
| } |
| else |
| { |
| have_ptrace_xmmregs = 0; |
| if (gdb_ptrace (PT_GETFPREGS, ptid, |
| (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) |
| perror_with_name (_("Couldn't get floating point status")); |
| |
| i387_collect_fsave (regcache, regnum, &fpregs); |
| |
| if (gdb_ptrace (PT_SETFPREGS, ptid, |
| (PTRACE_TYPE_ARG3) &fpregs, 0) == -1) |
| perror_with_name (_("Couldn't write floating point status")); |
| } |
| } |
| } |
| |
| void _initialize_i386bsd_nat (); |
| void |
| _initialize_i386bsd_nat () |
| { |
| /* To support the recognition of signal handlers, i386-bsd-tdep.c |
| hardcodes some constants. Inclusion of this file means that we |
| are compiling a native debugger, which means that we can use the |
| system header files and sysctl(3) to get at the relevant |
| information. */ |
| |
| #if defined (OpenBSD) |
| #define SC_REG_OFFSET i386obsd_sc_reg_offset |
| #endif |
| |
| #ifdef SC_REG_OFFSET |
| |
| /* We only check the program counter, stack pointer and frame |
| pointer since these members of `struct sigcontext' are essential |
| for providing backtraces. More checks could be added, but would |
| involve adding configure checks for the appropriate structure |
| members, since older BSD's don't provide all of them. */ |
| |
| #define SC_PC_OFFSET SC_REG_OFFSET[I386_EIP_REGNUM] |
| #define SC_SP_OFFSET SC_REG_OFFSET[I386_ESP_REGNUM] |
| #define SC_FP_OFFSET SC_REG_OFFSET[I386_EBP_REGNUM] |
| |
| /* Override the default value for the offset of the program counter |
| in the sigcontext structure. */ |
| int offset = offsetof (struct sigcontext, sc_pc); |
| |
| if (SC_PC_OFFSET != offset) |
| { |
| warning (_("\ |
| offsetof (struct sigcontext, sc_pc) yields %d instead of %d.\n\ |
| Please report this to <bug-gdb@gnu.org>."), |
| offset, SC_PC_OFFSET); |
| } |
| |
| SC_PC_OFFSET = offset; |
| |
| /* Likewise for the stack pointer. */ |
| offset = offsetof (struct sigcontext, sc_sp); |
| |
| if (SC_SP_OFFSET != offset) |
| { |
| warning (_("\ |
| offsetof (struct sigcontext, sc_sp) yields %d instead of %d.\n\ |
| Please report this to <bug-gdb@gnu.org>."), |
| offset, SC_SP_OFFSET); |
| } |
| |
| SC_SP_OFFSET = offset; |
| |
| /* And the frame pointer. */ |
| offset = offsetof (struct sigcontext, sc_fp); |
| |
| if (SC_FP_OFFSET != offset) |
| { |
| warning (_("\ |
| offsetof (struct sigcontext, sc_fp) yields %d instead of %d.\n\ |
| Please report this to <bug-gdb@gnu.org>."), |
| offset, SC_FP_OFFSET); |
| } |
| |
| SC_FP_OFFSET = offset; |
| |
| #endif /* SC_REG_OFFSET */ |
| } |