被realloc'd的指针未分配，在malloc_error_break中设置断点进行调试

Question

我一直在 Windows 上开发这个非常简单的 C 游戏，我使用命令gcc matches.c -o ./matches来编译它。我已将代码导入到 Mac 上，并使用gcc和重新编译了它clang。使用这两种技术，程序有时会完全崩溃，关闭我的终端会话并输出它。

matches(54122,0x1137715c0) malloc: *** error for object 0x7ffee9e8ba40: pointer being realloc'd was not allocated
matches(54122,0x1137715c0) malloc: *** set a breakpoint in malloc_error_break to debug
Abort trap: 6

Broadcast Message from _appleevents@(myname).local                                
        (no tty) at 20:33 CET...                                               

matches(54122,0x1137715c0) malloc: *** error for object 0x7ffee9e8ba40: pointer
 being realloc'd was not allocated

该代码在 Windows 上完全没有错误。

我认为这与 xcode 或类似的东西有关。有谁知道如何解决这个问题？

顺便说一句，这是代码。程序在设置功能中崩溃getline()

#include <stdio.h>
#include <stdlib.h>

void show_matches(int n);
void setup(int *numberOfPlayersA, int *gamemodeA, int *numberOfMatchesA);
void changePlayersTurn(int *currentPlayerA, int numberOfPlayers);
int random_move();

int main(void) {
  char *input;
  int currentPlayer = 1;
  size_t n = 0;
  int numberOfPlayers = 0;
  int gamemode = 0;
  int numberOfMatches = 0;
  int move = 0;

  setup(&numberOfPlayers, &gamemode, &numberOfMatches);
  show_matches(numberOfMatches);

  while (numberOfMatches >= 1) {
    printf("\033[1;31m");
    printf("\n\nPlayer %d> ", currentPlayer);
    printf("\033[0m");

    if (gamemode == 2 || currentPlayer == 1) {
      getline(&input, &n, stdin);
      move = atoi(input);

      if (move > 3 || move < 1 ) {
           move = 1;
      }
    } else {
      int randomMove = random_move();
      move = randomMove;
      printf("%d", randomMove);
    }



    numberOfMatches -= move;
    show_matches(numberOfMatches);


    if (numberOfMatches >= 1) {
      changePlayersTurn(&currentPlayer, numberOfPlayers);
    }
  }


  printf("\n\nPlayer %d lost\n\n", currentPlayer);

  return 0;
}

void setup(int *numberOfPlayersA, int *gamemodeA, int *numberOfMatchesA) {
  char *input;
  size_t n = 0;

  printf("--The matches--\n\n");
  printf("Do you plan on playing against:\n\t1. The computer\n\t2. Other persons\n\n(1 / 2) > ");
  getline(&input, &n, stdin);
  printf("1");
  *gamemodeA = atoi(input);
  printf("2");
  if (*gamemodeA == 2) {
    printf("\n\nPlease enter the number of players: ");
    getline(&input, &n, stdin);
    *numberOfPlayersA = atoi(input);
  }
  printf("Enter the number of matches: ");
  getline(&input, &n, stdin);
  *numberOfMatchesA = atoi(input);
  *numberOfPlayersA = 2;
  printf("4");
}

void changePlayersTurn(int *currentPlayerA, int numberOfPlayers) {
  if (*currentPlayerA == numberOfPlayers) {
    *currentPlayerA = 1;
  } else {
    *currentPlayerA += 1;
  }
}

void show_matches(int n) {
  for (int i = 0; i < n; i++) {
    printf("|");
  }
}

int random_move() {
  int num = (rand() % (3 - 1 + 1)) + 1;
  return num;
}

Answer 1

主要：​

 char *input;
 ...
 getline(&input, &n, stdin);

您在不初始化输入的情况下调用getline，如果（未定义）值不为 NULL getline将释放它，并且因为它不是已分配块的地址，所以您会遇到错误

例如你需要：

  input = NULL;
  getline(&input, &n, stdin);
  move = atoi(input);

  if (move > 3 || move < 1 ) {
       move = 1;
  }
  free(input);

您在设置中遇到类似的错误：

char *input;
...
getline(&input, &n, stdin);
...
getline(&input, &n, stdin);

您需要在第一次调用getline之前将输入设置为 NULL ，并且在最后一次调用之后需要释放，例如：

char *input;
...
input = NULL;
getline(&input, &n, stdin);
...
getline(&input, &n, stdin);
*numberOfMatchesA = atoi(input);
free(input);

附加说明：

• 你错过了检查getline的结果
• 使用atoi不安全，如果用户输入错误，你会得到0，最好使用strtod或sscanf
• 在main中，而不是在输入值不在 1 和 3 之间时强制为 1，最好重做输入