/*
 * Copyright 2002-2019 Intel Corporation.
 * 
 * This software is provided to you as Sample Source Code as defined in the accompanying
 * End User License Agreement for the Intel(R) Software Development Products ("Agreement")
 * section 1.L.
 * 
 * This software and the related documents are provided as is, with no express or implied
 * warranties, other than those that are expressly stated in the License.
 */

#include <stdio.h>
#include "pin.H"


ADDRINT origRtnAddress;
ADDRINT origRtnEndAddress;
ADDRINT substituteRtnAddress;
ADDRINT substituteRtnEndAddress;

int firstLoad = 1;
VOID ImageLoad(IMG img, VOID *v)
{
    RTN origRtn = RTN_FindByName(img, "_SetXto1");
    RTN substituteRtn = RTN_Invalid();

    if (RTN_Valid(origRtn))
    {
        substituteRtn = RTN_FindByName(img, "_SetXto2");
    }
    else
    {
        origRtn = RTN_FindByName(img, "SetXto1");
        if (RTN_Valid(origRtn))
        {
            substituteRtn = RTN_FindByName(img, "SetXto2");
        }
    }
    if (substituteRtn != RTN_Invalid())
    {
        origRtnAddress = RTN_Address(origRtn);
        origRtnEndAddress  = origRtnAddress + RTN_Size(origRtn);
        substituteRtnAddress = RTN_Address(substituteRtn);
        substituteRtnEndAddress  = substituteRtnAddress + RTN_Size(substituteRtn);
    }
}


// This function is called when the application exits
VOID Fini(INT32 code, VOID *v)
{
    
}

size_t ToolFetchFunction(void *buf, ADDRINT addr, size_t size, EXCEPTION_INFO *pExceptInfo, VOID *v)
{
    if (reinterpret_cast<ADDRINT>(v) != 0x11abcdef)
    {
        printf ("Got Bad Callback value\n"); 
    }
    ADDRINT addrToFetchFrom = addr;
        if ((addr >= origRtnAddress)
            && (addr <= (origRtnEndAddress)))
        {  // substitute with fetch from appropriate address in substituteRtn
            addrToFetchFrom = substituteRtnAddress + (addr - origRtnAddress);
//            printf ("ToolFetchFunction addr %x addrToFetchFrom %x \n",
//                   addr, addrToFetchFrom);
        }
    size_t copied = PIN_SafeCopyEx (static_cast<UINT8*>(buf),  
                                 reinterpret_cast<UINT8*>(addrToFetchFrom),  size, pExceptInfo);
//    printf ("ToolFetchFunction buf %p addr %x addrToFetchFrom %x size %d copied %d\n",
//                                buf, addr, addrToFetchFrom, size, copied);

    return (copied);
}

// argc, argv are the entire command line, including pin -t <toolname> -- ...
int main(int argc, char * argv[])
{
    PIN_InitSymbols();

    // Initialize pin
    PIN_Init(argc, argv);

    IMG_AddInstrumentFunction(ImageLoad, 0);

    PIN_AddFetchFunction(ToolFetchFunction, reinterpret_cast<VOID *>(0x11abcdef));

    // Register Fini to be called when the application exits
    PIN_AddFiniFunction(Fini, 0);
    
    // Start the program, never returns
    PIN_StartProgram();
    
    return 0;
}