/* Native-dependent code for FreeBSD/amd64. Copyright (C) 2003, 2004, 2007 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include "defs.h" #include "inferior.h" #include "regcache.h" #include "target.h" #include "gdb_assert.h" #include <signal.h> #include <stddef.h> #include <sys/types.h> #include <sys/ptrace.h> #include <sys/sysctl.h> #include <machine/reg.h> #include "fbsd-nat.h" #include "amd64-tdep.h" #include "amd64-nat.h" /* Offset in `struct reg' where MEMBER is stored. */ #define REG_OFFSET(member) offsetof (struct reg, member) /* At amd64fbsd64_r_reg_offset[REGNUM] you'll find the offset in `struct reg' location where the GDB register REGNUM is stored. Unsupported registers are marked with `-1'. */ static int amd64fbsd64_r_reg_offset[] = { REG_OFFSET (r_rax), REG_OFFSET (r_rbx), REG_OFFSET (r_rcx), REG_OFFSET (r_rdx), REG_OFFSET (r_rsi), REG_OFFSET (r_rdi), REG_OFFSET (r_rbp), REG_OFFSET (r_rsp), REG_OFFSET (r_r8), REG_OFFSET (r_r9), REG_OFFSET (r_r10), REG_OFFSET (r_r11), REG_OFFSET (r_r12), REG_OFFSET (r_r13), REG_OFFSET (r_r14), REG_OFFSET (r_r15), REG_OFFSET (r_rip), REG_OFFSET (r_rflags), REG_OFFSET (r_cs), REG_OFFSET (r_ss), -1, -1, -1, -1 }; /* Mapping between the general-purpose registers in FreeBSD/amd64 `struct reg' format and GDB's register cache layout for FreeBSD/i386. Note that most FreeBSD/amd64 registers are 64-bit, while the FreeBSD/i386 registers are all 32-bit, but since we're little-endian we get away with that. */ /* From <machine/reg.h>. */ static int amd64fbsd32_r_reg_offset[I386_NUM_GREGS] = { 14 * 8, 13 * 8, /* %eax, %ecx */ 12 * 8, 11 * 8, /* %edx, %ebx */ 20 * 8, 10 * 8, /* %esp, %ebp */ 9 * 8, 8 * 8, /* %esi, %edi */ 17 * 8, 19 * 8, /* %eip, %eflags */ 18 * 8, 21 * 8, /* %cs, %ss */ -1, -1, -1, -1 /* %ds, %es, %fs, %gs */ }; /* Support for debugging kernel virtual memory images. */ #include <sys/types.h> #include <machine/pcb.h> #include "bsd-kvm.h" static int amd64fbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb) { /* The following is true for FreeBSD 5.2: The pcb contains %rip, %rbx, %rsp, %rbp, %r12, %r13, %r14, %r15, %ds, %es, %fs and %gs. This accounts for all callee-saved registers specified by the psABI and then some. Here %esp contains the stack pointer at the point just after the call to cpu_switch(). From this information we reconstruct the register state as it would like when we just returned from cpu_switch(). */ /* The stack pointer shouldn't be zero. */ if (pcb->pcb_rsp == 0) return 0; pcb->pcb_rsp += 8; regcache_raw_supply (regcache, AMD64_RIP_REGNUM, &pcb->pcb_rip); regcache_raw_supply (regcache, AMD64_RBX_REGNUM, &pcb->pcb_rbx); regcache_raw_supply (regcache, AMD64_RSP_REGNUM, &pcb->pcb_rsp); regcache_raw_supply (regcache, AMD64_RBP_REGNUM, &pcb->pcb_rbp); regcache_raw_supply (regcache, 12, &pcb->pcb_r12); regcache_raw_supply (regcache, 13, &pcb->pcb_r13); regcache_raw_supply (regcache, 14, &pcb->pcb_r14); regcache_raw_supply (regcache, 15, &pcb->pcb_r15); regcache_raw_supply (regcache, AMD64_DS_REGNUM, &pcb->pcb_ds); regcache_raw_supply (regcache, AMD64_ES_REGNUM, &pcb->pcb_es); regcache_raw_supply (regcache, AMD64_FS_REGNUM, &pcb->pcb_fs); regcache_raw_supply (regcache, AMD64_GS_REGNUM, &pcb->pcb_gs); return 1; } /* Provide a prototype to silence -Wmissing-prototypes. */ void _initialize_amd64fbsd_nat (void); void _initialize_amd64fbsd_nat (void) { struct target_ops *t; int offset; amd64_native_gregset32_reg_offset = amd64fbsd32_r_reg_offset; amd64_native_gregset64_reg_offset = amd64fbsd64_r_reg_offset; /* Add some extra features to the common *BSD/i386 target. */ t = amd64bsd_target (); t->to_pid_to_exec_file = fbsd_pid_to_exec_file; t->to_find_memory_regions = fbsd_find_memory_regions; t->to_make_corefile_notes = fbsd_make_corefile_notes; add_target (t); /* Support debugging kernel virtual memory images. */ bsd_kvm_add_target (amd64fbsd_supply_pcb); /* To support the recognition of signal handlers, i386bsd-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. */ #define SC_REG_OFFSET amd64fbsd_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. */ #define SC_RIP_OFFSET SC_REG_OFFSET[AMD64_RIP_REGNUM] #define SC_RSP_OFFSET SC_REG_OFFSET[AMD64_RSP_REGNUM] #define SC_RBP_OFFSET SC_REG_OFFSET[AMD64_RBP_REGNUM] /* Override the default value for the offset of the program counter in the sigcontext structure. */ offset = offsetof (struct sigcontext, sc_rip); if (SC_RIP_OFFSET != offset) { warning (_("\ offsetof (struct sigcontext, sc_rip) yields %d instead of %d.\n\ Please report this to <bug-gdb@gnu.org>."), offset, SC_RIP_OFFSET); } SC_RIP_OFFSET = offset; /* Likewise for the stack pointer. */ offset = offsetof (struct sigcontext, sc_rsp); if (SC_RSP_OFFSET != offset) { warning (_("\ offsetof (struct sigcontext, sc_rsp) yields %d instead of %d.\n\ Please report this to <bug-gdb@gnu.org>."), offset, SC_RSP_OFFSET); } SC_RSP_OFFSET = offset; /* And the frame pointer. */ offset = offsetof (struct sigcontext, sc_rbp); if (SC_RBP_OFFSET != offset) { warning (_("\ offsetof (struct sigcontext, sc_rbp) yields %d instead of %d.\n\ Please report this to <bug-gdb@gnu.org>."), offset, SC_RBP_OFFSET); } SC_RBP_OFFSET = offset; /* FreeBSD provides a kern.ps_strings sysctl that we can use to locate the sigtramp. That way we can still recognize a sigtramp if its location is changed in a new kernel. Of course this is still based on the assumption that the sigtramp is placed directly under the location where the program arguments and environment can be found. */ { int mib[2]; long ps_strings; size_t len; mib[0] = CTL_KERN; mib[1] = KERN_PS_STRINGS; len = sizeof (ps_strings); if (sysctl (mib, 2, &ps_strings, &len, NULL, 0) == 0) { amd64fbsd_sigtramp_start_addr = ps_strings - 32; amd64fbsd_sigtramp_end_addr = ps_strings; } } }