我正在爲這個代碼苦苦掙扎。這是關於從文本文件中計算一些模式。我試圖使用線程(除法和征服)處理,但它返回了一個錯誤的值。我使用互斥量值來同步臨界區。代碼如下。第一個主要參數是線程數,第二個是我希望從中計數模式的文本文件的名稱,以及我希望查看文本的以下模式。 請救救我吧..我在多線程中遇到了一些問題
代碼如下
char *buffer;
int fsize, count;
char **searchword;
int *wordcount;
int *strlength;
typedef struct _params{
int num1;
int num2;
}params;
pthread_mutex_t mutex;
void *childfunc(void *arg)
{
int size, i, j, k, t, start, end, len, flag = -1;
int result;
params *a = (params *)arg;
start = a->num1;
end = a->num2;
while(1){
if(start == 0 || start == fsize)
break;
if(buffer[start]!= ' ' && buffer[start] != '\n' && buffer[start] != '\t')
start++;
else
break;
}
while(1){
if(end == fsize)
break;
if(buffer[end] != ' ' && buffer[end] != '\n' && buffer[end] != '\t')
end++;
else
break;
}
for(i = 0; i < count; i++){
len = strlength[i];
for(j = start; j<(end - len + 1); j++){
if(buffer[j] == searchword[i][0]){
flag = 0;
for(k = j +1; k<j + len; k++){
if(buffer[k] != searchword[i][k-j])
{
flag = 1;
break;
}
}
if(flag == 0){
pthread_mutex_lock(&mutex);
wordcount[i]++;
pthread_mutex_unlock(&mutex);// mutex unlocking
sleep(1);
flag = -1;
}
}
}
}
}
int main(int argc, char **argv){
FILE *fp;
char *inputFile;
pthread_t *tid;
int *status;
int inputNumber, i, j, diff, searchstart, searchend;
int result = 0;
count = argc -3;
inputNumber = atoi(argv[1]);
inputFile = argv[2];
searchword = (char **)malloc(sizeof(char *)*count);
tid = malloc(sizeof(pthread_t)*inputNumber);
strlength = (int *)malloc(4*count);
status = (int *)malloc(4*inputNumber);
wordcount = (int *)malloc(4*count);
for(i = 0; i < count; i++)
searchword[i] = (char*)malloc(sizeof(char)*(strlen(argv[i+3]) + 1));
for(i = 3; i < argc; i++)
strcpy(searchword[i-3], argv[i]);
fp = fopen(inputFile, "r");
fseek(fp, 0, SEEK_END);
fsize = ftell(fp);
rewind(fp);
buffer = (char *)malloc(1*fsize);
fread(buffer, fsize, 1, fp);
diff = fsize/inputNumber;
if(diff == 0)
diff = 1;
for(i = 0; i < count ; i++){
strlength[i] = strlen(searchword[i]);
wordcount[i] = 0;
}
for(i = 0; i < inputNumber; i++){
searchstart = 0 + i*diff;
searchend = searchstart + diff;
if(searchstart > fsize)
searchstart = fsize;
if(searchend > fsize)
searchend = fsize;
if(i == inputNumber -1)
searchend = fsize;
params a;
a.num1 = searchstart;
a.num2 = searchend;
pthread_mutex_init(&mutex, NULL);
result = pthread_create(&tid[i], NULL, childfunc, (void *)&a);
if(result < 0){
perror("pthread_create()");
}
}
//스레드 받는 부분
for(i = 0; i < inputNumber; i++){
result = pthread_join(tid[i], (void **)status);
if(result < 0)
perror("pthread_join()");
}
pthread_mutex_destroy(&mutex); // mutex 해제
for(i = 0; i < count; i++)
printf("%s : %d \n", searchword[i], wordcount[i]);
for(i = 0; i < count; i++) //동적메모리해제
free(searchword[i]);
free(searchword);
free(buffer);
free(tid);
free(strlength);
free(wordcount);
free(status);
fclose(fp);
return 0;
}
謝謝。你給了我一個見解。現在我要試試它! –