util/statetrace/arch/i686/tracechild.cc

   1 /*
   2  * Copyright (c) 2006 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Gabe Black
  29  */
  30
  31 #include <iostream>
  32 #include <errno.h>
  33 #include <sys/ptrace.h>
  34 #include <stdint.h>
  35
  36 #include "arch/i686/tracechild.hh"
  37
  38 using namespace std;
  39
  40 int64_t
  41 I686TraceChild::getRegs(user_regs_struct & myregs, int num)
  42 {
  43     assert(num < numregs && num >= 0);
  44     switch (num) {
  45       //GPRs
  46       case EAX: return myregs.eax;
  47       case EBX: return myregs.ebx;
  48       case ECX: return myregs.ecx;
  49       case EDX: return myregs.edx;
  50       //Index registers
  51       case ESI: return myregs.esi;
  52       case EDI: return myregs.edi;
  53       //Base pointer and stack pointer
  54       case EBP: return myregs.ebp;
  55       case ESP: return myregs.esp;
  56       //Segmentation registers
  57       case CS: return myregs.xcs;
  58       case DS: return myregs.xds;
  59       case ES: return myregs.xes;
  60       case FS: return myregs.xfs;
  61       case GS: return myregs.xgs;
  62       case SS: return myregs.xss;
  63       //PC
  64       case EIP: return myregs.eip;
  65       default:
  66         assert(0);
  67         return 0;
  68     }
  69 }
  70
  71 bool
  72 I686TraceChild::update(int pid)
  73 {
  74     oldregs = regs;
  75     if (ptrace(PTRACE_GETREGS, pid, 0, &regs) != 0)
  76         return false;
  77     for (unsigned int x = 0; x < numregs; x++) {
  78         regDiffSinceUpdate[x] = (getRegVal(x) != getOldRegVal(x));
  79     }
  80 }
  81
  82 I686TraceChild::I686TraceChild()
  83 {
  84     for (unsigned int x = 0; x < numregs; x++)
  85         regDiffSinceUpdate[x] = false;
  86 }
  87
  88 int64_t
  89 I686TraceChild::getRegVal(int num)
  90 {
  91     return getRegs(regs, num);
  92 }
  93
  94 int64_t
  95 I686TraceChild::getOldRegVal(int num)
  96 {
  97     return getRegs(oldregs, num);
  98 }
  99
 100 TraceChild *
 101 genTraceChild()
 102 {
 103     return new I686TraceChild;
 104 }