utils.cpp

/*
Copyright (c) 2009-2013, Intel Corporation
All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the dis
tribution.
    * Neither the name of Intel Corporation nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNES
S FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDI
NG, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRI
CT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// written by Andrey Semin

#include <iostream>
#include <cassert>
#include <climits>
#ifdef _MSC_VER
#include <process.h>
#include <comdef.h>
#else
#include <sys/wait.h> // for waitpid()
#include <unistd.h> // for ::sleep
#endif
#include "utils.h"
#include "cpucounters.h"

void (*post_cleanup_callback)(void) = NULL;

//! \brief handler of exit() call
void exit_cleanup(void)
{
    std::cout << std::flush;

    restore_signal_handlers();

    // this replaces same call in cleanup() from util.h
    PCM::getInstance()->cleanup(); // this replaces same call in cleanup() from util.h

//TODO: delete other shared objects.... if any.

    if(post_cleanup_callback != NULL)
    {
        post_cleanup_callback();
    }

// now terminate the program immediately
    _exit(EXIT_SUCCESS);
}

#ifdef _MSC_VER

ThreadGroupTempAffinity::ThreadGroupTempAffinity(uint32 core_id)
{
    GROUP_AFFINITY NewGroupAffinity;
    memset(&NewGroupAffinity, 0, sizeof(GROUP_AFFINITY));
    memset(&PreviousGroupAffinity, 0, sizeof(GROUP_AFFINITY));
    DWORD currentGroupSize = 0;

    while ((DWORD)core_id >= (currentGroupSize = GetActiveProcessorCount(NewGroupAffinity.Group)))
    {
        core_id -= (uint32)currentGroupSize;
        ++NewGroupAffinity.Group;
    }
    NewGroupAffinity.Mask = 1ULL << core_id;
    SetThreadGroupAffinity(GetCurrentThread(), &NewGroupAffinity, &PreviousGroupAffinity);
}
ThreadGroupTempAffinity::~ThreadGroupTempAffinity()
{
    SetThreadGroupAffinity(GetCurrentThread(), &PreviousGroupAffinity, NULL);
}

LONG unhandled_exception_handler(LPEXCEPTION_POINTERS p)
{
    std::cerr << "DEBUG: Unhandled Exception event" << std::endl;
    exit(EXIT_FAILURE);
}

/**
* \brief version of interrupt handled for Windows
*/
BOOL sigINT_handler(DWORD fdwCtrlType)
{
    // output for DEBUG only
    std::cerr << "DEBUG: caught signal to interrupt: ";
    switch (fdwCtrlType)
    {
    // Handle the CTRL-C signal.
    case CTRL_C_EVENT:
        std::cerr << "Ctrl-C event" << std::endl;
        break;

    // CTRL-CLOSE: confirm that the user wants to exit.
    case CTRL_CLOSE_EVENT:
        std::cerr << "Ctrl-Close event" << std::endl;
        break;

    // Pass other signals to the next handler.
    case CTRL_BREAK_EVENT:
        std::cerr << "Ctrl-Break event" << std::endl;
        break;

    case CTRL_LOGOFF_EVENT:
        std::cerr << "Ctrl-Logoff event" << std::endl;
        break;

    case CTRL_SHUTDOWN_EVENT:
        std::cerr << "Ctrl-Shutdown event" << std::endl;
        break;

    default:
        std::cerr << "Unknown event" << std::endl;
        break;
    }

    // TODO: dump summary, if needed

    // in case PCM is blocked just return and summary will be dumped in
    // calling function, if needed
    if (PCM::getInstance()->isBlocked()) {
        return FALSE;
    } else {
        exit_cleanup();
        return FALSE; // to prevent Warning
    }
}

/**
* \brief started in a separate thread and blocks waiting for child applicaiton to exit.
* After child app exits: -> print Child's termination status and terminates PCM
*/
void waitForChild(void * proc_id)
{
    intptr_t procHandle = (intptr_t)proc_id;
    int termstat;
    _cwait(&termstat, procHandle, _WAIT_CHILD);
    std::cerr << "Program exited with status " << termstat << std::endl;
    exit(EXIT_SUCCESS);
}
#else
/**
 * \brief handles signals that lead to termination of the program
 * such as SIGINT, SIGQUIT, SIGABRT, SIGSEGV, SIGTERM, SIGCHLD
 * this function specifically works when the client aplication launched
 * by pcm -- terminates
 */
void sigINT_handler(int signum)
{
    // output for DEBUG only
    std::cerr << "DEBUG: caught signal to interrupt (" << strsignal(signum) << ")." << std::endl;
    // TODO: dump summary, if needed

    // in case PCM is blocked just return and summary will be dumped in
    // calling function, if needed
    if (PCM::getInstance()->isBlocked())
        return;
    else
        exit_cleanup();
}

/**
 * \brief handles signals that lead to restart the application
 * such as SIGHUP.
 * for example to re-read environment variables controlling PCM execution
 */
void sigHUP_handler(int signum)
{
    // output for DEBUG only
    std::cerr << "DEBUG: caught signal to hangup. Reloading configuration and continue..." << std::endl;
    // TODO: restart; so far do nothing

    return; // continue program execution
}

/**
 * \brief handles signals that lead to update of configuration
 * such as SIGUSR1 and SIGUSR2.
 * for the future extensions
 */
void sigUSR_handler(int signum)
{
    std::cerr << "DEBUG: caught USR signal. Continue." << std::endl;
    // TODO: reload configurationa, reset accumulative counters;

    return;
}

/**
 * \brief handles signals that lead to update of configuration
 * such as SIGSTOP, SIGTSTP, SIGTTIN, SIGTTOU
 */
void sigSTOP_handler(int signum)
{
    PCM * m = PCM::getInstance();
    int runState = m->getRunState();
    std::string state = (runState == 1 ? "suspend" : "continue");
    std::cerr << "DEBUG: caught signal to " << state << " execution." << std::endl; // debug of signals only
    if (runState == 1) {
        // stop counters and sleep... almost forever;
        m->setRunState(0);
        sleep(INT_MAX);
    } else {
        // resume
        m->setRunState(1);
        alarm(1);
    }
    return;
}

/**
* \brief handles signals that lead to update of configuration
* such as SIGCONT
*/
void sigCONT_handler(int signum)
{
    std::cout << "DEBUG: caught signal to continue execution." << std::endl; // debug of signals only
    // TODO: clear counters, resume counting.
    return;
}
#endif // ifdef _MSC_VER

//! \brief install various handlers for system signals
void set_signal_handlers(void)
{
    if (atexit(exit_cleanup) != 0)
    {
        std::cerr << "ERROR: Failed to install exit handler." << std::endl;
        return;
    }

#ifdef _MSC_VER
    BOOL handlerStatus;
    // Increase the priority a bit to improve context switching delays on Windows
    SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_ABOVE_NORMAL);
// to fix Cygwin/BASH setting Ctrl+C handler need first to restore the default one
    handlerStatus = SetConsoleCtrlHandler(NULL, FALSE); // restores normal processing of CTRL+C input
    if (handlerStatus == 0) {
        std::wcerr << "Failed to set Ctrl+C hanlder. Error code: " << GetLastError() << " ";
        const TCHAR * errorStr = _com_error(GetLastError()).ErrorMessage();
        if (errorStr) std::wcerr << errorStr;
        std::wcerr << std::endl;
        _exit(EXIT_FAILURE);
    }
    SetConsoleCtrlHandler((PHANDLER_ROUTINE)sigINT_handler, TRUE);
    SetUnhandledExceptionFilter((LPTOP_LEVEL_EXCEPTION_FILTER)&unhandled_exception_handler);
    std::cerr << "DEBUG: Setting Ctrl+C done." << std::endl;

#else
    struct sigaction saINT, saHUP, saUSR, saSTOP, saCONT;

    // install handlers that interrupt execution
    saINT.sa_handler = sigINT_handler;
    sigemptyset(&saINT.sa_mask);
    saINT.sa_flags = SA_RESTART;
    sigaction(SIGINT, &saINT, NULL);
    sigaction(SIGQUIT, &saINT, NULL);
    sigaction(SIGABRT, &saINT, NULL);
    sigaction(SIGTERM, &saINT, NULL);
    sigaction(SIGSEGV, &saINT, NULL);

    saINT.sa_flags = SA_RESTART | SA_NOCLDSTOP;
    sigaction(SIGCHLD, &saINT, NULL); // get there is our child exits. do nothing if it stoped/continued

    // install SIGHUP handler to restart
    saHUP.sa_handler = sigHUP_handler;
    sigemptyset(&saHUP.sa_mask);
    saHUP.sa_flags = SA_RESTART;
    sigaction(SIGHUP, &saHUP, NULL);

    // install SIGHUP handler to restart
    saUSR.sa_handler = sigUSR_handler;
    sigemptyset(&saUSR.sa_mask);
    saUSR.sa_flags = SA_RESTART;
    sigaction(SIGUSR1, &saUSR, NULL);
    sigaction(SIGUSR2, &saUSR, NULL);

    // install SIGSTOP handler: pause/resume
    saSTOP.sa_handler = sigSTOP_handler;
    sigemptyset(&saSTOP.sa_mask);
    saSTOP.sa_flags = SA_RESTART;
    sigaction(SIGSTOP, &saSTOP, NULL);
    sigaction(SIGTSTP, &saSTOP, NULL);
    sigaction(SIGTTIN, &saSTOP, NULL);
    sigaction(SIGTTOU, &saSTOP, NULL);

    // install SIGCONT & SIGALRM handler
    saCONT.sa_handler = sigCONT_handler;
    sigemptyset(&saCONT.sa_mask);
    saCONT.sa_flags = SA_RESTART;
    sigaction(SIGCONT, &saCONT, NULL);
    sigaction(SIGALRM, &saCONT, NULL);

#endif
    return;
}

//! \brief Restores default signal handlers under Linux/UNIX
void restore_signal_handlers(void)
{
#ifndef _MSC_VER
    struct sigaction action;
    action.sa_handler = SIG_DFL;

    sigaction(SIGINT, &action, NULL);
    sigaction(SIGQUIT, &action, NULL);
    sigaction(SIGABRT, &action, NULL);
    sigaction(SIGTERM, &action, NULL);
    sigaction(SIGSEGV, &action, NULL);

    sigaction(SIGCHLD, &action, NULL);

    // restore SIGHUP handler to restart
    sigaction(SIGHUP, &action, NULL);

    // restore SIGHUP handler to restart
    sigaction(SIGUSR1, &action, NULL);
    sigaction(SIGUSR2, &action, NULL);

    // restore SIGSTOP handler: pause/resume
//     sigaction(SIGSTOP, &action, NULL); // cannot catch this
// handle SUSP character: normally C-z)
    sigaction(SIGTSTP, &action, NULL);
    sigaction(SIGTTIN, &action, NULL);
    sigaction(SIGTTOU, &action, NULL);

    // restore SIGCONT & SIGALRM handler
    sigaction(SIGCONT, &action, NULL);
    sigaction(SIGALRM, &action, NULL);
#endif

    return;
}

void set_post_cleanup_callback(void(*cb)(void))
{
    post_cleanup_callback = cb;
}

//!\brief launches external program in a separate process
void MySystem(char * sysCmd, char ** sysArgv)
{
    if (sysCmd == NULL) {
        assert("No program provided. NULL pointer");
        exit(EXIT_FAILURE);
    }
    std::cerr << std::endl << "Executing \"";
    std::cerr << sysCmd;
    std::cerr << "\" command:" << std::endl;
#ifdef _MSC_VER
    intptr_t ret;
    char cbuf[128];

    if (PCM::getInstance()->isBlocked()) {  // synchronous start: wait for child process completion
        // in case PCM should be blocked waiting for the child applicaiton to end
        // 1. returns and ret = -1 in case of error creating process is encountered
        // 2.
        ret = _spawnvp(_P_WAIT, sysCmd, sysArgv);
        if (ret == -1) { // process creation failed.
            strerror_s(cbuf, 128, errno);
            std::cerr << "Failed to start program \"" << sysCmd << "\". " << cbuf << std::endl;
            exit(EXIT_FAILURE);
        } else {         // process created, worked, and completed with exist code in ret. ret=0 -> Success
            std::cerr << "Program exited with status " << ret << std::endl;
        }
    } else {             // async start: PCM works in parallel with the child process, and exits when
        ret = _spawnvp(_P_NOWAIT, sysCmd, sysArgv);
        if (ret == -1) {
            strerror_s(cbuf, 128, errno);
            std::cerr << "Failed to start program \"" << sysCmd << "\". " << cbuf << std::endl;
            exit(EXIT_FAILURE);
        } else { // ret here is the new process handle.
            // start new thread which will wait for child completion, and continue PCM's execution
            if (_beginthread(waitForChild, 0, (void *)ret) == -1L) {
                strerror_s(cbuf, 128, errno);
                std::cerr << "WARNING: Failed to set waitForChild. PCM will countinue infinitely: finish it manually! " << cbuf << std::endl;
            }
        }
    }
#else
    pid_t child_pid = fork();

    if (child_pid == 0) {
        execvp(sysCmd, sysArgv);
        std::cerr << "Failed to start program \"" << sysCmd << "\"" << std::endl;
        exit(EXIT_FAILURE);
    }
    else
    {
        if (PCM::getInstance()->isBlocked()) {
            int res;
            waitpid(child_pid, &res, 0);
            std::cerr << "Program " << sysCmd << " launched with PID: " << child_pid << std::endl;

            if (WIFEXITED(res)) {
                std::cerr << "Program exited with status " << WEXITSTATUS(res) << std::endl;
            }
            else if (WIFSIGNALED(res)) {
                std::cerr << "Process " << child_pid << " was terminated with status " << WTERMSIG(res);
            }
        }
    }
#endif
}