Bdtjtk

any body who knows what happened to my program,i have enabled two signals,sigalarm & sigio,what is the meaning of COEF(), i googled it, little information about it. when my program crashed accidentally, segmentation fault showed in the shell command line

warning: core file may not match specified executable file.

[New LWP 162]

[New LWP 159]

Core was generated by `./main'.

Program terminated with signal SIGSEGV, Segmentation fault.

#0  0x00029a4c in COEF ()

[Current thread is 1 (LWP 162)]

(gdb) bt

#0  0x00029a4c in COEF ()

#1  <signal handler called>

#2  __libc_do_syscall () at ../ports/sysdeps/unix/sysv/linux/arm/libc-do-syscall.S:43

#3  0xb6f036e6 in do_futex_wait (isem=isem@entry=0xf67a8 <global_setting+24>)

    at ../nptl/sysdeps/unix/sysv/linux/sem_wait.c:48

#4  0xb6f03752 in __new_sem_wait (sem=0xf67a8 <global_setting+24>) at ../nptl/sysdeps/unix/sysv/linux/sem_wait.c:69

#5  0x00012286 in identify_task () at ./src/main.cpp:16

#6  0x000138ac in std::_Bind_simple<void (*())()>::_M_invoke<>(std::_Index_tuple<>) (this=0xbed2e8)

    at d:program files (x86)gcc-linaro-4.9.4-2017.01-i686-mingw32_arm-linux-gnueabihfarm-linux-gnueabihfincludec++4.9.4/functional:1700

#7  0x00013804 in std::_Bind_simple<void (*())()>::operator()() (this=0xbed2e8)

    at d:program files (x86)gcc-linaro-4.9.4-2017.01-i686-mingw32_arm-linux-gnueabihfarm-linux-gnueabihfincludec++4.9.4/functional:1688

#8  0x000137a6 in std::thread::_Impl<std::_Bind_simple<void (*())()> >::_M_run() (this=0xbed2dc)

    at d:program files (x86)gcc-linaro-4.9.4-2017.01-i686-mingw32_arm-linux-gnueabihfarm-linux-gnueabihfincludec++4.9.4/thread:115

#9  0xb6ec737c in std::execute_native_thread_routine (__p=<optimized out>)

    at /home/tcwg-buildslave/workspace/tcwg-make-release/label/docker-trusty-amd64-tcwg-build/target/arm-linux-gnueabihf/snapshots/gcc-linaro-4.9-2017.01/libstdc++-v3/src/c++11/thread.cc:84

#10 0xb6ef8e72 in (anonymous namespace)::get_safe_base_mutex(void*)::safe_base_mutex ()

   from C:msys64homezhangivanreleaseliblibstdc++.so.6

Backtrace stopped: previous frame identical to this frame (corrupt stack?)

(gdb) info symbol COEF

COEF in section .rodata of C:msys64homezhangivanreleasemain

(gdb)

i created a thread for processing data sent from signal handler timer_isr(int),below is the task i created

#define PATH_LEN 100

char pathstr[PATH_LEN] = {0};

void identify_task()

{

    int label = 0;

    uint8_t(*pic)[PIC_WIDTH] = NULL;

    int pic_height = 0;

    rs3_t rs3;



    for (;;)

    {

        sem_wait(&global_setting.identify_semaphore);



        pic_height = global_setting.pic_height;

        if (pic_height > MAX_HEIGHT || pic_height == 0)

        {

            continue;

        }



        /* get a pic buffer from  pic queue */

        if (dequeue(global_setting.pic_queue, reinterpret_cast<uint32_t *>(&pic)) == 0)

        {

            continue;

        }



        if (pic == NULL)

        {

            continue;

        }



#if DEBUG || MEASURE_TIME

        int begin = clock();

#endif

        if (1 == global_setting.is_predict)

        { /*do process predicting*/

            label = predict(pic, pic_height);

        }

        else

        { /* not do & assign a constant 10 */

            label = 10;

        }



#if DEBUG || MEASURE_TIME

        int end = clock();

        printf("cash label:%3d,predict time elapsed:%dn", label, end - begin);

#endif

        /* response a cash denomination value to control board */

        rs3.data[0] = 0;

        rs3.data[1] = label;

        rs3.chk = instruction_check<rs3_t>(&rs3);

        write(global_setting.uart_fd, &rs3, sizeof(rs3_t));



#if DEBUG || SAVE_PIC

        /* storage this picture and name each file with different suffix */

        static uint32_t picno = 0;

        memset(pathstr, 0, PATH_LEN);

        sprintf(pathstr, "./pics/128*%d_%d.bmp", pic_height, picno++);

        save_pic(pic, pic_height, pathstr);

#endif



        /* this pic buffer is used, so enqueue it into empty buffer */

        enqueue(global_setting.empty_queue, reinterpret_cast<uint32_t>(pic));

    }

}

here is my sigalarm handler,i noticed it crashed in it. this handler first sample some data using SPI, than post a semaphore

    void timer_isr(int signo)

{

    static int height = 0, lastheight = -1, start = 0;

    uint32_t sum = 0;



    if (spi_get_data(global_setting.spi_fd, spi_buf, PIC_WIDTH + 1) == 0)

    {

        return;

    }

    else

    {

        global_setting.system_status = RS1_NORMAL;

    }



    /* crc check */

    if (spi_buf[PIC_WIDTH] != crc_check(spi_buf, PIC_WIDTH))

    {

        return;

    }



#if PIC_TEST

    static int pic_test_i = 0;

    if (pic_test_i >= MAX_HEIGHT)

    {

        pic_test_i = 0;

    }

    memcpy(spi_buf, reinterpret_cast<uint8_t(*)[PIC_WIDTH]>(global_setting.test_pic)[pic_test_i], PIC_WIDTH);

    pic_test_i++;

#endif



    sum = get_sum<uint8_t>(spi_buf, PIC_WIDTH);



    /* scan for 5000 times & get smallest boundary value */

    if (boundary_cnter < 5000)

    {

        if (global_setting.boundary > sum)

        {

            global_setting.boundary = sum;

        }



        boundary_cnter++;

        return;

    }

    else if (boundary_cnter == 5000)

    {

        global_setting.boundary -= 700;

        boundary_cnter++;

    }



    /* here we compare sum with initial asured boundary

        if sum is smaller than boundary, then store this

        pixel data

     */

#if PIC_TEST

    if (sum < 4000)

#else

    if (sum < global_setting.boundary)

#endif

    {

        /* pic started */

        start = 1;



        /* if pic buffer is null, so pick one pic buffer from empty queue */

        if (pic == NULL)

        {

            if (dequeue(global_setting.empty_queue, reinterpret_cast<uint32_t *>(&pic)) == 0)

            {

                return;

            }



            if (pic == NULL)

            {

                return;

            }

        }



        memcpy(pic[height], spi_buf, PIC_WIDTH);



        if (height < (MAX_HEIGHT - 1))

        {

            height++;

        }

    }



    /* here if all these condictions are met, well, full cash picture is sampled */

    if (start == 1 && height - lastheight == 0 && height > 0)

    {

        /* enqueue this pic buffer into on using queue */

        if (enqueue(global_setting.pic_queue, reinterpret_cast<uint32_t>(pic)) == 1)

        {

            global_setting.pic_height = height;



            /* notify identify_task */

            sem_post(&global_setting.identify_semaphore);



            /* now this pic buffer is used,so reset pic pointer */

            pic = NULL;

            height = 0;

            start = 0;

        }

    }



    lastheight = height;

}

and below is my timer_isr(int) regester function

int timer_init(void fun(int),int us)

{

    int res = 0;

    struct itimerval tick; 



    signal(SIGALRM, fun);

    memset(&tick, 0, sizeof(tick));



    //Timeout to run first time

    tick.it_value.tv_sec = 0;

    tick.it_value.tv_usec = 200;



    //After first, the Interval time for clock

    tick.it_interval.tv_sec = 0;

    tick.it_interval.tv_usec = us;



    if(setitimer(ITIMER_REAL, &tick, NULL) < 0)

    {

        printf("Set timer failed!n");

        return -1;

    }



    return 0;

}

i checked my process stack is 8192KB, it could not be caused by stack overflow