Question

有4个.c / .h文件。每个都有一些全局变量＆amp;结构变量。我从.map文件中获取了所有变量名称。我在二维数组/ * array []（char类型）中提取了所有内容。现在我想传递每个变量和地址的sizeof

Answer 1

确定。如果需要在变量中分配动态内存，则需要在“stdlib.h”中使用malloc函数并读取该文件，您可以将其存储到链表中以逐个处理。

检查示例...... 我们在这个语义中有一个'variables.map'：

eua 40
brasil 30
paris 15
horse 8

第一列是变量的名称（最多40个字符参见struct prototype ），第二列是大小。（注意：由换行'\ n'分开）

程序将文件加载到内存中的链表中并分配相应的内存空间（检查main（））。

参见示例程序......

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

//MAP prototype
typedef struct map {
    char name[40];
    unsigned int size;

    struct map *next;
} map;
//---

//Prototypes
void createList();
void insert(char[], int, map*);
void showList(map*);
unsigned int searchVariable(char[], map*);
void parseMapFile(char[]);
//---

//List, Linked list pointer
map *list_variables;
//---

//Main!
int main(int argc, const char * argv[])
{
    //Create list!
    createList();

    //Parse the .Map file into struct
    parseMapFile("/Users/gabriel/Documents/variables.map");

    //Show linked list
    //showList(list_variables);

    //------
    //Lets go now allocate the variables with the size in .map file

    //Allocate space!
    //Tipical types
    int   *eua    = malloc(searchVariable("eua", list_variables) * sizeof(int));
    char  *brasil = malloc(searchVariable("brasil", list_variables) * sizeof(char));
    float *paris  = malloc(searchVariable("paris", list_variables) * sizeof(float));

    //Alloc the void type (Undefined)
    void  *horse  = malloc(searchVariable("horse", list_variables) * sizeof(void));
    //---

    //Set values
    *eua = 5; //Integer
    strcpy(brasil, "Cool!"); //String
    *paris = 3.14; //Float
    *(int*)horse = (int) 7; //Set a integer value to void pointer!
    //---

    //Show up!
    printf("Variable eua: %d \n", *eua);
    printf("Variable brasil: %s \n", brasil);
    printf("Variable paris: %f \n", *paris);
    printf("Variable horse: %d \n", *((int*)horse));

    return EXIT_SUCCESS;
}


//Linked list functions...
//Allocate the linked list on memory
void createList() {
    list_variables = malloc( sizeof (map));
    list_variables->next = NULL;
}

//Insert the .MAP values into linked list
void insert(char name[], int size, map *p)
{
    map *new;

    new = malloc( sizeof (map));

    new->size = size;
    strcpy(new->name, name);
    new->next = p->next;
    p->next = new;
}

//Show variables loaded from .MAP file
void showList(map *list)
{
    map *p;
    for (p = list->next; p != NULL; p = p->next)
        printf("Variable: %s, Size: %d \n", p->name, p->size);
}

//Search variable in memory and return the size respective
unsigned int searchVariable(char name[], map *list)
{
    map *p;
    p = list->next;

    while (p != NULL && strcmp(name, p->name) != 0)
        p = p->next;

    return p->size;
}
//---

//Procedure to parse the map file in the specified structure!
void parseMapFile(char path[]) {
    char line[80];
    char name[40];
    unsigned int size;

    FILE *fp = fopen(path, "r");

    while(fgets(line, 80, fp) != NULL)
    {
        sscanf (line, "%s %d", name, &size);

        insert(name, size, list_variables);
    }

    fclose(fp);
}

有了这个，你真的可以用存储在文件中的值来分配动态空间。

是否有可能找到结构变量的大小和地址;运行期间的全局变量？

1 个答案: