Question

我在sprintf方面遇到问题。它似乎正在修改我的代码的其他部分。我正在从扩展名为.j的文件中读取令牌。但在此之前，我通过从文件中删除.j扩展名，使用pathname.j文件名在文件中创建标签：

j_file是路径名。j：

//Initialize length of j_file pathname
    j_file_len = strlen(j_file);

    //Initialize
    char if_label[j_file_len];
    char else_label[j_file_len];
    char endif_label[j_file_len];

在这里，我从原始路径名中删除.j扩展名，并将其添加到三个单独的变量中，以便新文件扩展名仅是路径名

for (i = 0; i < j_file_len - 2; i++)
        {
            if_label[i] = j_file[i];
            else_label[i] = j_file[i];
            endif_label[i] = j_file[i];
        }

        //Place null terminator
        if_label[j_file_len - 2] = '\0';
        else_label[j_file_len - 2] = '\0';
        endif_label[j_file_len - 2] = '\0';

        //Length of concatenated string
        len_concat = strlen(if_label);

在这里，我在文件中搜索“ if”标记，然后将字符串连接到if_label的末尾，并fprint到文件。

    //If token is if
    else if (strcmp(tail->token, "if") == 0)
    {
        printf("There are %d IFS\n",if_count );

        printf("IF FOUND\n");

        sprintf(if_count_string, "_IF_%d", if_count);

        strcat(if_label, if_count_string);

        printf("If CONCAT is  %s \n",if_label );


        //Else will match to IF
        else_count = if_count;

        //Create ELSE label for branching

        sprintf(else_count_string, "_ELSE_%d", else_count);

        strcat(else_label, else_count_string);

        printf("Else CONCAT is %s \n",else_label );

        ////

        ///**** EDIT
        //Open file
        FILE *ASM = fopen(asm_file, "a");

        //Perform operation
        fprintf(ASM, "\t; === %s ===\n", tail->token);

        //Create IF label
        fprintf(ASM, "%s\n",if_label);

        //Copy element at top of stack to register
        fprintf(ASM, "\tLDR R0, R6, #0\n");

        //Clear element from stack
        fprintf(ASM, "\tCONST R2, #0\n");
        fprintf(ASM, "\tHICONST R2, #0\n");
        fprintf(ASM, "\tSTR R2, R6, #0\n");

        //Increment stack pointer to point to next element on stack
        fprintf(ASM, "\tADD R6, R6, #1\n");

        //Compare elements element to 0 (element - 0)
        fprintf(ASM, "\tCMPI R0 #0\n");


        //If operation false (= 0) Branch to corresponding else label
        fprintf(ASM, "\tBRz %s\n", else_label);

        //****/

        //Close file
        fclose(ASM);

        //Remove IF label identifier
        for (i = len_concat; if_label[i] != '\0'; i++)
        {
            if_label[i] = '\0';

        }

        len = strlen(if_label);

        printf("new length of if label is %d\n", len);
        printf("Trimmed IF IS %s\n",if_label );

        //Remove ELSE label identifier
         for (i = len_concat; else_label[i] != '\0'; i++)
         {
            else_label[i] = '\0';

         }

        len = strlen(else_label);
        printf("new length of else label is %d\n", len);
        printf("Trimmed ELSE IS %s\n",else_label );

        //Increment if counter
        if_count++;

    }

我期望的输出是，在每次for循环迭代到代码结尾时，修整后的IF和修整后的ELSe应该只打印pathname：

If CONCAT is  pathname_IF_0
Else CONCAT is pathname_ELSE_0
new length of if label is 8
Trimmed IF IS pathname 
new length of else label is 8 
Trimmed ELSE IS pathname

但是我的IF语句被我不知道的某个代理神秘地修改了。观察代表性输出：

If CONCAT is  pathname_IF_0 //CORRECT
Else CONCAT is pathname_ELSE_0 //CORRECT
new length of if label is 1//NOT CORRECT
Trimmed IF IS 0 //WHY?!?!?!?
new length of else label is 8 //CORRECT
Trimmed ELSE IS pathname

由于此if块发生在循环中，因此它弄乱了我的代码的后续迭代。为什么会这样呢？我为此打了个头，无济于事。任何帮助表示赞赏。

编辑：计数变量和字符串变量在if bock之外初始化

int if_count = 0;
int else_count = 0;

char if_count_string[100];
char else_count_string[100];

fprintf意外修改了字符串

0 个答案: