| /* |
| * This file is part of ltrace. |
| * Copyright (C) 2013 Petr Machata, Red Hat Inc. |
| * Copyright (C) 1998,2002,2004,2008,2009 Juan Cespedes |
| * Copyright (C) 2009 Juan Cespedes |
| * |
| * 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 St, Fifth Floor, Boston, MA |
| * 02110-1301 USA |
| */ |
| |
| #include "config.h" |
| |
| #include <sys/types.h> |
| #include <sys/ptrace.h> |
| #include <asm/ptrace.h> |
| #include <errno.h> |
| |
| #include "proc.h" |
| #include "common.h" |
| #include "regs.h" |
| |
| #if (!defined(PTRACE_PEEKUSER) && defined(PTRACE_PEEKUSR)) |
| # define PTRACE_PEEKUSER PTRACE_PEEKUSR |
| #endif |
| |
| #if (!defined(PTRACE_POKEUSER) && defined(PTRACE_POKEUSR)) |
| # define PTRACE_POKEUSER PTRACE_POKEUSR |
| #endif |
| |
| int |
| arm_get_register(struct process *proc, enum arm_register reg, uint32_t *lp) |
| { |
| errno = 0; |
| long l = ptrace(PTRACE_PEEKUSER, proc->pid, (void *)(reg * 4L), 0); |
| if (l == -1 && errno != 0) |
| return -1; |
| *lp = (uint32_t)l; |
| return 0; |
| } |
| |
| int |
| arm_set_register(struct process *proc, enum arm_register reg, uint32_t lp) |
| { |
| return ptrace(PTRACE_PEEKUSER, proc->pid, |
| (void *)(reg * 4L), (void *)lp); |
| } |
| |
| int |
| arm_get_register_offpc(struct process *proc, enum arm_register reg, |
| uint32_t *lp) |
| { |
| if (arm_get_register(proc, reg, lp) < 0) |
| return -1; |
| if (reg == ARM_REG_PC) |
| *lp += 8; |
| return 0; |
| } |
| |
| int |
| arm_get_shifted_register(struct process *proc, uint32_t inst, int carry, |
| arch_addr_t pc_val, uint32_t *lp) |
| { |
| enum arm_register rm = BITS(inst, 0, 3); |
| unsigned long shifttype = BITS(inst, 5, 6); |
| |
| uint32_t shift; |
| if (BIT(inst, 4)) { |
| if (arm_get_register_offpc(proc, BITS(inst, 8, 11), &shift) < 0) |
| return -1; |
| shift &= 0xff; |
| } else { |
| shift = BITS(inst, 7, 11); |
| } |
| |
| uint32_t res; |
| if (rm == ARM_REG_PC) |
| /* xxx double cast */ |
| res = (uintptr_t)pc_val + (BIT(inst, 4) ? 12 : 8); |
| else if (arm_get_register(proc, rm, &res) < 0) |
| return -1; |
| |
| switch (shifttype) { |
| case 0: /* LSL */ |
| res = shift >= 32 ? 0 : res << shift; |
| break; |
| |
| case 1: /* LSR */ |
| res = shift >= 32 ? 0 : res >> shift; |
| break; |
| |
| case 2: /* ASR */ |
| if (shift >= 32) |
| shift = 31; |
| res = ((res & 0x80000000L) |
| ? ~((~res) >> shift) : res >> shift); |
| break; |
| |
| case 3: /* ROR/RRX */ |
| shift &= 31; |
| if (shift == 0) |
| res = (res >> 1) | (carry ? 0x80000000L : 0); |
| else |
| res = (res >> shift) | (res << (32 - shift)); |
| break; |
| } |
| |
| *lp = res & 0xffffffff; |
| return 0; |
| } |
| |
| static arch_addr_t |
| get_register_nocheck(struct process *proc, enum arm_register r) |
| { |
| uint32_t reg; |
| if (arm_get_register(proc, r, ®) < 0) |
| /* XXX double cast. */ |
| return (arch_addr_t)-1; |
| /* XXX double cast. */ |
| return (arch_addr_t)(uintptr_t)reg; |
| } |
| |
| arch_addr_t |
| get_instruction_pointer(struct process *proc) |
| { |
| return get_register_nocheck(proc, ARM_REG_PC); |
| } |
| |
| void |
| set_instruction_pointer(struct process *proc, arch_addr_t addr) |
| { |
| /* XXX double cast. */ |
| arm_set_register(proc, ARM_REG_PC, (uint32_t)addr); |
| } |
| |
| void * |
| get_stack_pointer(struct process *proc) |
| { |
| return get_register_nocheck(proc, ARM_REG_SP); |
| } |
| |
| arch_addr_t |
| get_return_addr(struct process *proc, arch_addr_t stack_pointer) |
| { |
| return get_register_nocheck(proc, ARM_REG_LR); |
| } |