无法在共享 memory 中共享结构数组

Question

我创建了一个库来初始化和填充 strutc 共享 2 进程数组。 问题是它不起作用，而是我创建了一个 int 数组并且它可以正常工作。 但是我需要共享 memory 中的这个数组，我想念什么？

EDIT: I have a theory but I need confirmation cause i'm studing now c and sh memory....is possible taht the problem are the transaction declared by pointer in the struct of block, and for that reason in the sh memory doesn '没有任何结果？这个错误迫使进程因某种原因关闭？

编辑：所以我忘了张贴打印 function。 我将大小强制为 0，因为我只想插入 1 个元素并且至少只打印一个。 但是打印 function 在 if 之前的第一次打印之后卡住了，我不知道为什么。 我认为这是因为共享不起作用，但对于打印“Blocco n°0”，它表明Masterbook[i].id内部有一些价值。

编辑：更改了char*但也不起作用。

结构：

struct Transaction {
    char timestamp[24];
    int sender; /* pid user sent */
    int receiver;
    int reward;
    int money;
};

struct Block
{
    int id;
    struct Transaction* tr1;
    struct Transaction* tr2;
    struct Transaction* reward;
};

masterbook.c

    struct Block* MasterBook;
    int sizeMaster = -1;
        void initMasterBook(){
            int shmid,sizeid;
            shmid = shmget(SH_KEY_MASTERBOOK,MAX_MASTER*sizeof(struct Block),IPC_CREAT | 0666);
            if(shmid == -1) {
                perror("shmget error");
                exit(EXIT_FAILURE);
            }
            MasterBook = (struct Block*)shmat(shmid,NULL,0);
            if ( MasterBook == -1 ) {
                perror ( "Error in shmat: " );
                exit(EXIT_FAILURE);
            }
               
        }
        
        void freeMasterBook(){
            shmdt((void *) MasterBook); 
        }
        int addBlock(struct Block block){
            if(sizeMaster >= MAX_MASTER-1) return -1;
            ++sizeMaster;
            block.id = sizeMaster;
            MasterBook[sizeMaster] = block;
            return 0;
        }
int printMasterBook(){
    if(sizeMaster < 0) {
        printf("\nMasterbook vuoto");
        return -1;
    }
    int i = 0;
    for ( i; i <= sizeMaster; i++)
    {
        printf("\nBlocco n° : %d",MasterBook[i].id);
        
        if(MasterBook[i].tr1 != NULL){
            printf("\n\tTransazione n° 1 : ");
        struct Transaction *temp = MasterBook[i].tr1;
        printf("\n\t\tReceiver: %d",temp->receiver);
        printf("\n\t\tSender: %d",temp->sender);
        printf("\n\t\tReward: %d",temp->reward);
        printf("\n\t\tTimestamp: %s",temp->timestamp);
        }else printf("\nThere's no transaction 1 set!");

        if(MasterBook[i].tr2 != NULL){
            printf("\n\tTransazione n° 2 : ");
        struct Transaction *temp2 = MasterBook[i].tr2;
        printf("\n\t\tReceiver: %d",temp2->receiver);
        printf("\n\t\tSender: %d",temp2->sender);
        printf("\n\t\tReward: %d",temp2->reward);
        printf("\n\t\tTimestamp: %s",temp2->timestamp);
        }else printf("\nThere's no transaction 2 set!");

        if(MasterBook[i].reward != NULL){
            printf("\n\tTransazione Reward : ");
        struct Transaction *temp3 = MasterBook[i].reward;
        printf("\n\t\tReceiver: %d",temp3->receiver);
        printf("\n\t\tSender: %d",temp3->sender);
        printf("\n\t\tReward: %d",temp3->reward);
        printf("\n\t\tTimestamp: %s",temp3->timestamp);
        }else printf("\nThere's no transaction reward set!");
    
        printf("finish print");
    }
    return 0;
}

master.c：

initMasterBook();
printf("\nthe size id: %d",sizeMaster);
printMasterBook();
struct Block v;
struct Transaction t1;
t1.money = 4;
t1.receiver = 2;
t1.sender = 3;
strcpy(t1.timestamp,"ciao");
t1.reward = 4;
v.tr1 = &t1;
addBlock(v);
printMasterBook();
 printf("\nthe size id: %d",sizeMaster);

节点.c

int main(int argc, char const *argv[])
{
    initMasterBook();
    sizeMaster=0;
    printMasterBook();
    freeMasterBook();
    return 0;
}

Answer 1

我解决了 output 更改结构中的指针并重新排列代码的问题。

struct Transaction {
    int empty;
    char timestamp[30];
    int sender; /* pid user sent */
    int receiver;
    int reward;
    int money;
};

struct Block
{
    int id;
    struct Transaction tr1;
    struct Transaction tr2;
    struct Transaction reward;
};

有问题的打印：

int printMasterBook(){
    if(sizeMaster < 0) {
        printf("\nMasterbook vuoto");
        return -1;
    }
    int i = 0;
    for ( i; i <= sizeMaster; i++)
    {
        printf("\nBlocco n° : %d",MasterBook[i].id);
        
        if(MasterBook[i].tr1.empty != -1){
            printf("\n\tTransazione n° 1 : ");
        printf("\n\t\tReceiver: %d",MasterBook[i].tr1.receiver);
        printf("\n\t\tSender: %d",MasterBook[i].tr1.sender);
        printf("\n\t\tReward: %d",MasterBook[i].tr1.reward);
        printf("\n\t\tTimestamp: %s",MasterBook[i].tr1.timestamp);
        }else printf("\nThere's no transaction 1 set!");

        if(MasterBook[i].tr2.empty!= -1){
            printf("\n\tTransazione n° 2 : ");
        printf("\n\t\tReceiver: %d",MasterBook[i].tr2.receiver);
        printf("\n\t\tSender: %d",MasterBook[i].tr2.sender);
        printf("\n\t\tReward: %d",MasterBook[i].tr2.reward);
        printf("\n\t\tTimestamp: %s",MasterBook[i].tr2.timestamp);
        }else printf("\nThere's no transaction 2 set!");

        if(MasterBook[i].reward.reward != -1){
            printf("\n\tTransazione Reward : ");
        printf("\n\t\tReceiver: %d",MasterBook[i].reward.receiver);
        printf("\n\t\tSender: %d",MasterBook[i].reward.sender);
        printf("\n\t\tReward: %d",MasterBook[i].reward.reward);
        printf("\n\t\tTimestamp: %s",MasterBook[i].reward.timestamp);
        }else printf("\nThere's no transaction reward set!");
    
        printf("finish print");
    }
    return 0;
}