重新分配+ memcpy 2D 浮点数组导致分段错误

Question

我制作了一个带有浮子数组的结构（Somemisc），因此我可以填充一些值，然后尝试将其浮点数阵列记忆到其他结构的浮点阵列，然后打印出结果以查看它是否有效。

另一个结构（arraypairs）应该容纳两个阵列。因此，当我想对“一对”进行一些更改时，低[i]属于高[i]，反之亦然。

因此，我制作了2个somemismisc对象，用数字填充数组，然后尝试在我扩展带有Realloc的Arraypairs对象的低阵列和高阵列的地方，然后我尝试将新行悬挂到新行，然后最终来自给出的两个Somemisc成员阵列的Memcpy内容作为函数的参数。

但这会导致细分故障和/或未定义的行为，我不知道为什么。

#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <time.h>
#include <stdlib.h>

typedef struct some{
  int32_t len;
  float* arr;
} SomeMisc;

typedef struct arrPrs{
  int32_t amountOfRows;
  int32_t amountOfColumns;
  float** low;
  float** high;
} ArrayPairs;

void initializeArrayPairArray(ArrayPairs* AP, int32_t length, int32_t width){

  AP->amountOfRows = length;
  AP->amountOfColumns = width;

  AP->low = (float**)malloc(length * sizeof(float*));
  AP->high = (float**)malloc(length * sizeof(float*));

  for(int i=0; i<length; i++){
    AP->low[i] = (float*)malloc(width * sizeof(float));
    AP->high[i] = (float*)malloc(width * sizeof(float));
    for(int j=0; j<width; j++){
      AP->low[i][j] = 32;
      AP->high[i][j] = 44;
    }
  }
}

void addArrayPair(ArrayPairs* AP, float* low, float* high){
  AP->amountOfRows++;

  AP->low = (float**)realloc(AP->low, AP->amountOfRows * sizeof(float*));
  AP->high = (float**)realloc(AP->high, AP->amountOfRows * sizeof(float*));

  AP->low[AP->amountOfRows] = (float*)malloc(AP->amountOfColumns * sizeof(float));
  AP->high[AP->amountOfRows] = (float*)malloc(AP->amountOfColumns * sizeof(float));

  memcpy(AP->low[AP->amountOfRows], low, AP->amountOfColumns * sizeof(float));
  memcpy(AP->high[AP->amountOfRows], high, AP->amountOfColumns * sizeof(float));

  printf("TESTING PRINT: %.2f\n", AP->high[10][5]);
}

int main () {
  int32_t nrOfCols = 8;
  int32_t nrOfRows = 10;

  ArrayPairs arr;
  initializeArrayPairArray(&arr, nrOfRows, nrOfCols);

  int32_t mArrLength = 2;
  SomeMisc* mArr = (SomeMisc*)malloc(mArrLength*sizeof(SomeMisc));
  for(int i=0; i<mArrLength; i++){
    mArr[i].arr = (float*)malloc(nrOfCols*sizeof(float));
    for(int j=0; j<nrOfCols; j++){
      mArr[i].arr[j] = (i+1)*j;
    }
  }

  addArrayPair(&arr, mArr[0].arr, mArr[1].arr);

  printf("LOW:\tHIGH:\n");
  for(int i=9; i<arr.amountOfRows; i++){
    printf("INDEX: %d\n",i);
    for(int j=0; j<arr.amountOfColumns; j++){
      printf("%.2f\t%.2f\n",arr.low[i][j],arr.high[i][j]);
    }
    printf("\n");
  }

  return(0);
}

我遵循了此答案： 2D arreay realloc seggentation dudd efform误差

但是我已经有arraypairs* ap在addarraypair的参数列表中，以及＆amp;带有object arr时＆amp; 。

我还尝试了该答案所建议的那样进行删除，但这也没有用：

void addArrayPair(ArrayPairs* AP, float* low, float* high){
  (*AP).amountOfRows++;

  (*AP).low = (float**)realloc((*AP).low, AP->amountOfRows * sizeof(float*));
  (*AP).high = (float**)realloc((*AP).high, AP->amountOfRows * sizeof(float*));

  (*AP).low[AP->amountOfRows] = (float*)malloc((*AP).amountOfColumns * sizeof(float));
  (*AP).high[AP->amountOfRows] = (float*)malloc((*AP).amountOfColumns * sizeof(float));

  memcpy((*AP).low[(*AP).amountOfRows], low, (*AP).amountOfColumns * sizeof(float));
  memcpy((*AP).high[(*AP).amountOfRows], high, (*AP).amountOfColumns * sizeof(float));
}

Answer 1

您会为时过早增加ap-＆gt; MANTEROFROWS。这意味着，当您进行ap-＆gt; low [ap-＆gt; noseofrows]时，您将使用距离索引，并具有 dem> nofection crathive

而不是（re）分配ap-＆gt; MANTEROFROWS + 1元素，并增加ap-＆gt; MANTEROFROWS一旦完成了所有分配和复制：

void addArrayPair(ArrayPairs* AP, float* low, float* high){
  AP->low = realloc(AP->low, (AP->amountOfRows + 1) * sizeof(float*));
  AP->high = realloc(AP->high, (AP->amountOfRows + 1) * sizeof(float*));

  AP->low[AP->amountOfRows] = malloc(AP->amountOfColumns * sizeof(float));
  AP->high[AP->amountOfRows] = malloc(AP->amountOfColumns * sizeof(float));

  memcpy(AP->low[AP->amountOfRows], low, AP->amountOfColumns * sizeof(float));
  memcpy(AP->high[AP->amountOfRows], high, AP->amountOfColumns * sizeof(float));

  // Increase once all is done
  AP->amountOfRows++;
}