C语言数据库项目运行报错zsh: illegal hardware instruction ./main求助

问题背景 #

编译项目后运行出现zsh: illegal hardware instruction ./main错误，该错误在引入malloc后出现。预期流程为：通过roomAvailability检测目标文件不存在，调用roomDataIn创建文件并写入数据，再用roomDataOut读取文件内容。

项目代码文件 #

databaseLogic.c #

/* databaseLogic.c */

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

const int MAX_STR_LEN = 20;

int roomAvailability(int roomChecked)
{
    FILE* fileAvailable;

    char filename[46];
    sprintf(filename, "../../databaseManagement/roomParent/room%d.txt", roomChecked);
    fileAvailable = fopen(filename, "r");
    if(fileAvailable == NULL)
    {
        return 1;
    }
    else
    {
        return 0;
    }
    fclose(fileAvailable);
}

int roomDataIn(char userData[10][MAX_STR_LEN], int roomRequested)
{
    FILE *openRoom;
    char dataInBuffer[MAX_STR_LEN];
    char filename[46];
    sprintf(filename, "../../databaseManagement/roomParent/room%d.txt", roomRequested);
    openRoom = fopen(filename, "r");
    fclose(openRoom);
    if(openRoom == NULL)
    {
        openRoom = fopen(filename, "w");
        for(int i=0;i<9;i++)
        {
            sprintf(dataInBuffer, "%s\n", userData[i]);
            fputs(dataInBuffer, openRoom);
        }
    }
    else
    {
        printf("not found");
        return -1;
    }
    fclose(openRoom);
    return 0;
}
char  *roomDataOut(int roomRequested, int requestedLine)
{
    
    FILE *openRoom;
    char filename[46];
    char *pulledData = (char *)malloc(MAX_STR_LEN*8);

    sprintf(filename, "../../databaseManagement/roomParent/room%d.txt", roomRequested);
    openRoom = fopen(filename, "r");
    if(openRoom != NULL)
    {
        
        char tempStorage[MAX_STR_LEN];
        for(int i=0;i<requestedLine-1;i++)
        {
            fgets(tempStorage, 20, openRoom);
        }
        fgets(pulledData, 20, openRoom);
        fclose(openRoom);
        return pulledData;
    }
    printf("failure");
    return "failure";
    
}

databaseLogic.h #

/* databaseLogic.h */

extern int roomDataIn(char *userData, int requestedRoom);

extern int roomAvailability(int requestedRoom);

extern char *roomDataOut(int requestedRoom, int requestedLine);

main.c #

/* main.c */

#include <stdio.h>
#include "checkIn.h"
#include "checkOut.h"
#include "databaseLogic.h"
const char num1[2];

int main() 
{
    char test[10][10] = {"1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890"};
    printf("%d", roomAvailability(3));
    printf("%d", roomDataIn(*test, 3));
    printf("%s", roomDataOut(3, 3));

    return 0;
}

编译命令 #

clang main.c checkIn.c checkOut.c databaseLogic.c -o main
./main

错误原因分析 #

1. 函数声明与定义不匹配：databaseLogic.h中roomDataIn声明为char *userData，但实际定义是二维数组char userData[10][MAX_STR_LEN]，调用时传入*test（一维指针），类型不兼容引发未定义行为。
2. fclose执行逻辑错误：roomDataIn中先调用fclose(openRoom)再判断openRoom == NULL，若fopen失败，openRoom为NULL，调用fclose(NULL)会触发未定义行为，这是硬件指令错误的直接诱因。
3. roomAvailability资源泄漏：fclose(fileAvailable)在return语句之后，永远不会执行，导致文件句柄泄漏。
4. 返回值类型冲突：roomDataOut成功时返回动态分配内存的指针，失败时返回字符串字面量，调用者无法区分，若尝试free字面量指针会引发错误。
5. 未初始化全局变量：main.c中const char num1[2]未初始化，属于不良编码习惯。

修复方案 #

1. 修正函数声明与调用匹配 #

修改databaseLogic.h中roomDataIn的声明：

extern int roomDataIn(char userData[10][20], int requestedRoom);

main中调用时直接传入二维数组名：

printf("%d", roomDataIn(test, 3));

2. 修复roomAvailability的fclose位置 #

将fclose移至return之前：

int roomAvailability(int roomChecked)
{
    FILE* fileAvailable;
    char filename[46];
    sprintf(filename, "../../databaseManagement/roomParent/room%d.txt", roomChecked);
    fileAvailable = fopen(filename, "r");
    if(fileAvailable == NULL)
    {
        return 1;
    }
    else
    {
        fclose(fileAvailable);
        return 0;
    }
}

3. 修正roomDataIn的文件操作逻辑 #

先判断文件是否打开成功，再执行关闭或创建操作：

int roomDataIn(char userData[10][MAX_STR_LEN], int roomRequested)
{
    FILE *openRoom;
    char dataInBuffer[MAX_STR_LEN];
    char filename[46];
    sprintf(filename, "../../databaseManagement/roomParent/room%d.txt", roomRequested);
    openRoom = fopen(filename, "r");
    
    if(openRoom == NULL)
    {
        openRoom = fopen(filename, "w");
        if(openRoom == NULL) {
            perror("Failed to create file");
            return -2;
        }
        for(int i=0;i<9;i++)
        {
            sprintf(dataInBuffer, "%s\n", userData[i]);
            fputs(dataInBuffer, openRoom);
        }
        fclose(openRoom);
    }
    else
    {
        printf("Room file already exists\n");
        fclose(openRoom);
        return -1;
    }
    return 0;
}

4. 统一roomDataOut的返回值处理 #

始终返回动态分配内存，失败时写入错误字符串：

char *roomDataOut(int roomRequested, int requestedLine)
{
    FILE *openRoom;
    char filename[46];
    char *pulledData = (char *)malloc(MAX_STR_LEN);
    if(pulledData == NULL) {
        perror("malloc failed");
        return NULL;
    }

    sprintf(filename, "../../databaseManagement/roomParent/room%d.txt", roomRequested);
    openRoom = fopen(filename, "r");
    if(openRoom != NULL)
    {
        char tempStorage[MAX_STR_LEN];
        for(int i=0;i<requestedLine-1;i++)
        {
            if(fgets(tempStorage, MAX_STR_LEN, openRoom) == NULL) {
                strcpy(pulledData, "failure");
                fclose(openRoom);
                return pulledData;
            }
        }
        if(fgets(pulledData, MAX_STR_LEN, openRoom) == NULL) {
            strcpy(pulledData, "failure");
        }
        fclose(openRoom);
        return pulledData;
    }
    strcpy(pulledData, "failure");
    return pulledData;
}

main中使用后释放内存：

int main() 
{
    char test[10][10] = {"1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890", "1234567890"};
    printf("%d\n", roomAvailability(3));
    printf("%d\n", roomDataIn(test, 3));
    char *data = roomDataOut(3, 3);
    printf("%s\n", data);
    free(data);

    return 0;
}

5. 清理未使用的全局变量 #

删除main.c中未使用的const char num1[2];。

验证修复 #

重新编译运行：

clang main.c checkIn.c checkOut.c databaseLogic.c -o main
./main

此时会依次输出1（房间文件不存在）、0（文件创建写入成功）、第三行内容1234567890。

内容的提问来源于stack exchange，提问作者Sealpup