/*
 * 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 <iostream>
#include <fstream>
#include <ostream>
#include <string>
#include <vector>
#include "pin.H"
#include "create_and_exit_thread_utils.h"

using std::cerr;
using std::endl;
using std::ostream;
using std::ofstream;
using std::string;
using std::vector;


/**************************************************
 * Global variables                               *
 **************************************************/

const unsigned int fiveMinutesInMilliseconds = 5 * 60 * 1000;
const unsigned int maxNumTests = 500;

volatile unsigned int numThreads = 0;
volatile unsigned int testCounter = 0;
volatile bool finiCalled = false;
volatile THREADID currTid = INVALID_THREADID;
volatile THREADID nextTid = INVALID_THREADID;

PIN_SEMAPHORE noActiveThreads;

ostream* outFile = NULL;

KNOB<string> KnobOutputFile(KNOB_MODE_WRITEONCE,  "pintool",
    "o", "", "Specify file name for the tool's output. If no filename is specified, the output will be directed to stderr.");


/**************************************************
 * Analysis routines                              *
 **************************************************/

void DoTest(const THREADID tid, CONTEXT* ctxt)
{
    *outFile << "TOOL: Thread " << tid << " executing DoTest." << endl;

    if (!PIN_SemaphoreTimedWait(&noActiveThreads, fiveMinutesInMilliseconds))
    {
        PIN_ExitProcess(RETVAL_FAILURE_TEST_TIMEOUT);
    }
    PIN_SemaphoreClear(&noActiveThreads);

    if (maxNumTests > testCounter)
    {
        BOOL ret = PIN_SpawnApplicationThread(ctxt);
        if (!ret)
        {
            *outFile << "TOOL ERROR: Failed to spawn new application thread." << endl;
            PIN_ExitProcess(RETVAL_FAILURE_TOOL_FAILED_TO_SPAWN);
        }
    }
    PIN_ExitThread(RETVAL_SUCCESS);

    *outFile << "TOOL ERROR: Should not reach this point in DoTest." << endl;
    PIN_ExitProcess(RETVAL_FAILURE_TOOL_FAILED_TO_EXIT);
}


/**************************************************
 * Instrumentation routines                       *
 **************************************************/

VOID Instruction(INS ins, VOID* v)
{
    INS_InsertCall(ins, IPOINT_BEFORE, AFUNPTR(DoTest), IARG_THREAD_ID, IARG_CONTEXT, IARG_END);
}


/**************************************************
 * Callback functions                             *
 **************************************************/

VOID ThreadStart(const THREADID tid, CONTEXT* ctxt, INT32 flags, VOID* v)
{
    ASSERTX(INVALID_THREADID == nextTid);

    if (finiCalled)
    {
        cerr << "TOOL ERROR: ThreadStart called after application Fini." << endl;
        PIN_ExitProcess(RETVAL_FAILURE_START_AFTER_FINI);
    }

    if (maxNumTests < testCounter)
    {
        PIN_ExitProcess(RETVAL_FAILURE_MAX_TRIALS);
    }
    ++testCounter;

    if (0 == numThreads)
    {
        ASSERTX(INVALID_THREADID == currTid);
        ASSERTX(PIN_SemaphoreIsSet(&noActiveThreads));
        ++numThreads;
        currTid = tid;
    }
    else if (1 == numThreads)
    {
        ASSERTX(INVALID_THREADID != currTid);
        ASSERTX(!PIN_SemaphoreIsSet(&noActiveThreads));
        ++numThreads;
        nextTid = tid;
    }
    else
    {
        PIN_ExitProcess(RETVAL_FAILURE_TOO_MANY_THREADS);
    }
}


VOID ThreadFini(const THREADID tid, const CONTEXT* ctxt, INT32 code, VOID* v)
{
    ASSERTX(tid == currTid);
    ASSERTX(!PIN_SemaphoreIsSet(&noActiveThreads));
    *outFile << "TOOL: ThreadFini for thread " << tid << " with code " << code << "." << endl;
    --numThreads;
    currTid = nextTid;
    nextTid = INVALID_THREADID;
    PIN_SemaphoreSet(&noActiveThreads);
}


VOID Fini(INT32 code, VOID* v)
{
    ASSERTX(0 == numThreads);
    *outFile << "TOOL: Fini called after " << testCounter << " trials." << endl;
    finiCalled = true;
    if (&cerr != outFile)
    {
        delete outFile;
    }
    PIN_SemaphoreFini(&noActiveThreads);
}


/**************************************************
 * Main function                                  *
 **************************************************/

int main(int argc, char* argv[])
{
    if(PIN_Init(argc, argv)) return RETVAL_FAILURE_PIN_INIT_FAILED;

    if (!PIN_SemaphoreInit(&noActiveThreads)) return RETVAL_FAILURE_SEMAPHORE_INIT_FAILED;
    PIN_SemaphoreSet(&noActiveThreads);

    outFile = KnobOutputFile.Value().empty() ? &cerr : new ofstream(KnobOutputFile.Value().c_str());

    INS_AddInstrumentFunction(Instruction, 0);

    PIN_AddThreadStartFunction(ThreadStart, 0);
    PIN_AddThreadFiniFunction(ThreadFini, 0);
    PIN_AddFiniFunction(Fini, 0);

    PIN_StartProgram();
    return RETVAL_FAILURE_TOOL_MAIN_RETURN;
}