我正在爲一款紙牌遊戲編寫一個C程序,而且我正在制定算法來爲每個玩家發牌。問題是,似乎沒有理由,我的數組指針在執行過程中被設置爲0,我無法弄清楚原因。它似乎發生在我的代碼中的一個非常特定的地方。這裏就是我聲明數組:我的C數組在執行期間被破壞
struct Hand *hands = (struct Hand*)calloc(players, sizeof(struct Hand));
for (int player = 0; player < leftovers; player++) {
//Allocate an extra spot for these players, since they take an
//extra card
hands[player].cardv = (struct Card*)calloc((cardsperplayer + 1), sizeof(struct Card));
hands[player].cardc = cardsperplayer + 1;
}
for (int player = leftovers; player < players; player++) {
//Allocate the normal amount of cards for the rest of the players
hands[player].cardv = (struct Card*)calloc((cardsperplayer), sizeof(struct Card));
hands[player].cardc = cardsperplayer;
}
接下來,我們跳過,我做出一副撲克牌,並與卡值填充它,到了那裏,我洗牌在甲板上的點的部分,準備好處理它們。似乎只要洗牌結束,指向手陣列的指針就會變差。
//Then we add the jokers on the end
struct Card blackJoker = {0, 13};
deck[52] = blackJoker;
struct Card redJoker = {1, 13};
deck[53] = redJoker;
//Now, we shuffle the deck using the Fisher Yates shuffle (the Durstenfeld version)
for (int cardsleft = 54; cardsleft > 0; cardsleft--) {
swapCards(deck, cardsleft, rand() % cardsleft);
}
//IT SEEMS TO DROP THE HANDS ARRAY RIGHT HERE...run
//Now that the cards are randomly shuffled, we just deal them out to
// everyone (it doesn't matter about the order, this is supposed to
//be truly random!
currentCard = 0;
for (int player = 0; player < leftovers; player++) {
//Deal an extra card for these players, since they take an extra
//card
for (int card = 0; card < hands[player].cardc; card++) {
hands[player].cardv[card] = deck[currentCard];
currentCard++;
}
}
我沒有得到的東西是,直接在之前或之後的手陣列訪問。但仍然,手陣列結束了死亡,我得到一個Segfault試圖訪問一個瘋狂的地址。我將包含代碼的其他部分,以供參考。
void swapCards(struct Card *set, int a, int b) {
struct Card temp = set[a];
set[a] = set[b];
set[b] = temp;
這是我做存儲卡和手的結構:
struct Card {
int suit;
int value;
};
struct Hand {
int cardc;
struct Card* cardv;
};
如果你想運行完整的應用程序,它是託管在Github上一個C程序,在https://github.com/Mikumiku747/kingandserf 它不應該需要除C編譯器和make外的任何先決條件。至於一些決定性的證據,我把它通過調試,這是我發現那裏一切都錯了一點:
Reading symbols from /home/pi/kingandtheserf/bin/kats...done.
(gdb) b cardops.c:90
Breakpoint 1 at 0x8a58: file src/cardops.c, line 90.
(gdb) b cardops.c:94
Breakpoint 2 at 0x8aa8: file src/cardops.c, line 94.
(gdb) b cardops.c:98
Note: breakpoint 2 also set at pc 0x8aa8.
Breakpoint 3 at 0x8aa8: file src/cardops.c, line 98.
(gdb) run a a a
Starting program: /home/pi/kingandtheserf/bin/kats a a a
Breakpoint 1, dealHands (players=4, sort=0) at src/cardops.c:91
91 for (int cardsleft = 54; cardsleft > 0; cardsleft--) {
(gdb) p hands
$1 = (struct Hand *) 0x13008
(gdb) p hands[0]
$2 = {cardc = 14, cardv = 0x13030}
(gdb) p hands[2]
$3 = {cardc = 13, cardv = 0x13120}
(gdb) c
Continuing.
Breakpoint 2, dealHands (players=4, sort=0) at src/cardops.c:98
98 currentCard = 0;
(gdb) p hands
$4 = (struct Hand *) 0x2
(gdb) p hands[0]
Cannot access memory at address 0x2
(gdb) c
Continuing.
Program received signal SIGSEGV, Segmentation fault.
0x00008b30 in dealHands (players=4, sort=0) at src/cardops.c:102
102 for (int card = 0; card < hands[player].cardc; card++) {
(gdb) quit
即使有人不知道如何解決這個問題,可能他們至少告訴我發生了什麼事。我以前從未見過這種情況,現在我唯一的猜測是優化器以某種方式破壞了它。
請張貼所有的變量聲明。看哪,我可以看到未來:這將成爲一個錯綜複雜的數組索引錯誤。 – Lundin
好的,我添加了hands數組的聲明。感謝您查看它。如果您需要其他任何東西,我只會發布完整的標題和代碼,其中大約80%已經存在。 – Mikumiku747