util/statetrace/arch/tracechild_i386.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 "tracechild_i386.hh"
  37
  38 using namespace std;
  39
  40 char * I386TraceChild::regNames[numregs] = {
  41                 //GPRs
  42                 "eax", "ebx", "ecx", "edx",
  43                 //Index registers
  44                 "esi", "edi",
  45                 //Base pointer and stack pointer
  46                 "ebp", "esp",
  47                 //Segmentation registers
  48                 "cs", "ds", "es", "fs", "gs", "ss",
  49                 //PC
  50                 "eip"};
  51
  52 int64_t I386TraceChild::getRegs(user_regs_struct & myregs, int num)
  53 {
  54         assert(num < numregs && num >= 0);
  55         switch(num)
  56         {
  57                 //GPRs
  58                 case EAX: return myregs.eax;
  59                 case EBX: return myregs.ebx;
  60                 case ECX: return myregs.ecx;
  61                 case EDX: return myregs.edx;
  62                 //Index registers
  63                 case ESI: return myregs.esi;
  64                 case EDI: return myregs.edi;
  65                 //Base pointer and stack pointer
  66                 case EBP: return myregs.ebp;
  67                 case ESP: return myregs.esp;
  68                 //Segmentation registers
  69                 case CS: return myregs.cs;
  70                 case DS: return myregs.ds;
  71                 case ES: return myregs.es;
  72                 case FS: return myregs.fs;
  73                 case GS: return myregs.gs;
  74                 case SS: return myregs.ss;
  75                 //PC
  76                 case EIP: return myregs.eip;
  77                 default:
  78                         assert(0);
  79                         return 0;
  80         }
  81 }
  82
  83 bool I386TraceChild::update(int pid)
  84 {
  85         oldregs = regs;
  86         if(ptrace(PTRACE_GETREGS, pid, 0, &regs) != 0)
  87                 return false;
  88         for(unsigned int x = 0; x < numregs; x++)
  89         {
  90                 regDiffSinceUpdate[x] =
  91                         (getRegVal(x) != getOldRegVal(x));
  92         }
  93 }
  94
  95 I386TraceChild::I386TraceChild()
  96 {
  97         for(unsigned int x = 0; x < numregs; x++)
  98                 regDiffSinceUpdate[x] = false;
  99 }
 100
 101 int64_t I386TraceChild::getRegVal(int num)
 102 {
 103         return getRegs(regs, num);
 104 }
 105
 106 int64_t I386TraceChild::getOldRegVal(int num)
 107 {
 108         return getRegs(oldregs, num);
 109 }
 110
 111 char * I386TraceChild::printReg(int num)
 112 {
 113         sprintf(printBuffer, "0x%08X", getRegVal(num));
 114         return printBuffer;
 115 }
 116
 117 TraceChild * genTraceChild()
 118 {
 119         return new I386TraceChild;
 120 }