在为FIR过滤器编写C程序时，面临程序崩溃的问题。 奇怪的是在调试模式下，没有发现任何奇怪的现象。代码正常运行。 但是在运行时崩溃。使用的IDE是代码块。
请在下面找到代码段
main.c
#include "common.h"
#include "carrier_NCO_generation.h"
#include "lfsr.h"
int main()
{
int *nco_out = NULL,*noise_out = NULL,*carrier_gen_I = NULL,*carrier_gen_Q = NULL,*inp_data_I = NULL,*inp_data_Q = NULL;
int *complex_product_I = NULL,*complex_product_Q = NULL,*FIR_I_Data = NULL,*FIR_Q_Data = NULL;
int i;
nco_out = (int *)malloc(SAMPLES*sizeof(int));
noise_out = (int *)malloc(SAMPLES*sizeof(int));
carrier_gen_I = (int *)malloc(SAMPLES*sizeof(int));
carrier_gen_Q = (int *)malloc(SAMPLES*sizeof(int));
inp_data_I = (int *)malloc(SAMPLES*sizeof(int));
inp_data_Q = (int *)malloc(SAMPLES*sizeof(int));
complex_product_I = (int *)malloc(SAMPLES*sizeof(int));
complex_product_Q = (int *)malloc(SAMPLES*sizeof(int));
FIR_I_Data = (int *)malloc(SAMPLES*sizeof(int));
FIR_Q_Data = (int *)malloc(SAMPLES*sizeof(int));
fileRead(1,SAMPLES,inp_data_I,"rf_sam_i.txt",1);
fileRead(1,SAMPLES,inp_data_Q,"rf_sam_q.txt",1);
carrier_NCO(nco_out);
lfsr(noise_out);
carrier_generation(nco_out,noise_out,carrier_gen_I,carrier_gen_Q);
frequency_transpose(carrier_gen_I,carrier_gen_Q,inp_data_I,inp_data_Q,complex_product_I,complex_product_Q);
fir(complex_product_I,complex_product_Q,FIR_I_Data,FIR_Q_Data);
/*
File Record
*/
fileRecord(1,SAMPLES,nco_out,"Carrier_NCO_out.txt",0);
free(nco_out);
fileRecord(1,SAMPLES,noise_out,"Carrier_NOISE_out.txt",0);
free(noise_out);
fileRecord(1,SAMPLES,carrier_gen_I,"Carrier_gen_I_out.txt",0);
free(carrier_gen_I);
fileRecord(1,SAMPLES,carrier_gen_Q,"Carrier_gen_Q_out.txt",0);
free(carrier_gen_Q);
fileRecord(1,SAMPLES,complex_product_I,"Freq_Trans_I_out.txt",0);
free(complex_product_I);
fileRecord(1,SAMPLES,complex_product_Q,"Freq_Trans_Q_out.txt",0);
free(complex_product_Q);
fileRecord(1,SAMPLES,FIR_I_Data,"FIR_I_Data_out.txt",0);
free(FIR_I_Data);
fileRecord(1,SAMPLES,FIR_Q_Data,"FIR_Q_Data_out.txt",0);
free(FIR_Q_Data);
return 0;
}
问题出在FIR过滤器中，代码在下面给出
FIR.C
#include "fir.h"
void array_multiplication(int *array_data, int coefficients[], int size)
{
int i = 0;
for(i = 0; i<size; i++)
{
array_data[i] = array_data[i]*coefficients[i];
}
}
int array_addition(int *array_data, int size)
{
int i = 0,sum = 0;
for(i = 0; i<size; i++)
{
sum = sum + array_data[i];
}
return sum;
}
void shift_array_elements(int *array_data, int size)
{
int i = 0;
for(i=size;i>0;i--)
{
array_data[i] = array_data[i-1];
}
}
int symmetrical_rounding_without_bit_extension_8_bit_fir(int number)
{
int bit_7 = 0,neg_flag = 0,max_negtve = -1048576, max_postve = 1048448;
int mask_number = 2097024;
//printf("number at input = %d\n",number);
if((number < 0)&&(number <= -1048576))
{
return max_negtve;
}
else if((number > 0)&&(number >= 1048448))
{
return max_postve;
}
else if(number < 0)
{
number = ((number) * (-1));
neg_flag = 1;
}
bit_7 = bitExtracted(number,1,7);
number = number & mask_number;
if(bit_7)
{
number = number + 128;
}
if(neg_flag == 1)
{
number = (number * (-1));
}
return number;
}
int symmetrical_saturation_on_8_th_bit(int number)
{
int mask_with = 0x7F,neg_flag = 0,max_negtve = -127, max_postve = 128;
if((number < 0)&&(number <= max_negtve))
{
return max_negtve;
}
else if((number > 0)&&(number >= max_postve))
{
return max_postve;
}
else if(number == 0)
{
return 0;
}
else if(number < 0)
{
number = ((number) * (-1));
neg_flag = 1;
}
number = number & mask_with;
if(number == 0)
{
number = max_postve;
}
if(neg_flag == 1)
{
number = (number * (-1));
}
return (int)number;
}
void fir(int *complex_I_data,int *complex_Q_data,int *I_data_out,int *Q_data_out)
{
int i = 0,j =0,k = 0,real_sum = 0,imag_sum = 0;
int *real_part = NULL,*imag_part = NULL,*inp_real_part = NULL,*inp_imag_part = NULL;
real_part = (int *)malloc(FIR_COEFFICIENT * sizeof(int));
imag_part = (int *)malloc(FIR_COEFFICIENT * sizeof(int));
inp_real_part = (int *)malloc(FIR_COEFFICIENT * sizeof(int));
inp_imag_part = (int *)malloc(FIR_COEFFICIENT * sizeof(int));
//Initialize to 0.
for(i =0; i<FIR_COEFFICIENT; i++)
{
real_part[i] = 0;
imag_part[i] = 0;
inp_real_part[i] = 0;
inp_imag_part[i] = 0;
}
for(i = 0; i<SAMPLES; i++)
{
inp_real_part[0] = complex_I_data[i];
inp_imag_part[0] = complex_Q_data[i];
for(j = 0; j<FIR_COEFFICIENT; j++)
{
real_part[j] = inp_real_part[j];
imag_part[j] = inp_imag_part[j];
}
//Array multiplication
array_multiplication(real_part,precumul_fir_coeff_i,FIR_COEFFICIENT);
array_multiplication(imag_part,precumul_fir_coeff_q,FIR_COEFFICIENT);
//sum of array elements
real_sum = array_addition(real_part,FIR_COEFFICIENT);
imag_sum = array_addition(imag_part,FIR_COEFFICIENT);
real_sum = symmetrical_rounding_without_bit_extension_8_bit_fir(real_sum);
imag_sum = symmetrical_rounding_without_bit_extension_8_bit_fir(imag_sum);
I_data_out[i] = symmetrical_saturation_on_8_th_bit(real_sum);
Q_data_out[i] = symmetrical_saturation_on_8_th_bit(imag_sum);
//shifting array elements
if((i < (SAMPLES-1)))
{
//printf("Reached\n");
shift_array_elements(inp_real_part,FIR_COEFFICIENT);
shift_array_elements(inp_imag_part,FIR_COEFFICIENT);
}
}
real_part = NULL;
imag_part = NULL;
inp_real_part = NULL;
inp_imag_part = NULL;
free(real_part);
free(imag_part);
free(inp_real_part);
free(inp_imag_part);
}
在FIR.C中，Free引发错误，因此将变量分配为NULL。让我知道这是否是错误的。 另外，SAMPLES = 100。
请让我知道我要去哪里了。
谢谢。
答案 0 :(得分：1)
代码不完整，因此我无法验证，但是函数shift_array_elements似乎超出范围：
void shift_array_elements(int *array_data, int size)
{
int i = 0;
for(i=size;i>0;i--)
{
array_data[i] = array_data[i-1];
}
}
从i = size开始，这是从fir（）函数调用时超出的范围：
if((i < (SAMPLES-1)))
{
//printf("Reached\n");
shift_array_elements(inp_real_part,FIR_COEFFICIENT);
shift_array_elements(inp_imag_part,FIR_COEFFICIENT);
}
这里的最后一个元素是inp_real_part[FIR_COEFFICIENT-1]，但是shift_array_elements将分配给inp_real_part[FIR_COEFFICIENT]。
-g -O2进行编译并通过gdb运行exectuable，以从崩溃中获取堆栈跟踪malloc将返回NULL。使用malloc/free之前，请务必先检查返回的值。