Copy void* content into SigLib struct SLData_t*

问题

I am doing an Windows application using C++. I have the next dude.

I have this function where I receive a void * with data audio capture:

void Pre_proc_mono::PreProcess(void *data, int lenbytes) {
    SLData_t *signal1;
    SLData_t *signal2;
    SLData_t *result;
    signal1 = (SLData_t*)data;
    signal2 = new SLData_t[lenbytes];
    result = new SLData_t[2 * lenbytes - 1];

    for (int i = 0; i < lenbytes; i++){
        signal2[i] = signal1[i];
    }
}

The loop always fail around 11000, why? What am I doing wrong ? The idea is then do a correlation cross with SigLib library (DSP library). So I need have arrays with limit, not pointers so I am doing this instead. Help?

EDIT: First, when I said fails I want to say that when loop reaches to around 11000 appears and runtime error. Second SLData_t is a kind of date of the SigLib library, and the function to doing correlation cross need this variable as input.

回答1:

Following may help:

void Pre_proc_mono::PreProcess(void *data, int lenbytes) {
    SLData_t* signal1 = reinterpret_cast<SLData_t*>(data);
    const std::size_t signalCount = lenbytes / sizeof (SLData_t);
    // then if you want to copy inside a std::vector
    std::vector<SLData_t> signal2(signal1, signal1 + signalCount);
}

回答2:

This could be implemented far better, safe, and simple using std::vector instead of manual-memory-management and std::copy():

void Pre_proc_mono::PreProcess(void *data, std::size_t lenbytes){

    SLData_t *signal1 = (SLData_t*)data;
    std::size_t data_length = lenbytes / sizeof( SLData_t );
    std::vector<SLData_t> signal2;
    std::vector<SLData_t> result;

    std::copy( std::begin( signal1 ) , 
               std::end( signal1 ) + data_length , 
               std::back_inserter( signal2 ) 
             );
}

来源：https://stackoverflow.com/questions/20838389/copy-void-content-into-siglib-struct-sldata-t

标签

c++

windows

signal-processing