我有这个函数，只有在可用并且所请求的字节数的大小适合我的小型托管内存时，它才会接收多个字节来分配和发送回。 我的问题:
没有分配适当的数据结构，我担心我将无法取回正确的地址。有谁知道如何在另一个程序中使用它作为库来测试这个函数？
数据结构
typedef struct memBlock{
struct memBlock* next;
unsigned long size; // Size of this block
unsigned int is_used; // bool 0 = not used 1 = used
} memBlock;
MALLOC 函数:
char *mm_alloc(unsigned long no_of_chars){
if (!has_initialized) {
printf("No Memory has been intialized, PLEASE INITIALIZE THE MEMORY BEFORE calling This function\n");
exit(1);
}
void *cur_location; // this is where we are currentl in our memory pool
memBlock *current_loc_mb; // the current mem block location
char *mem_location; // mem location we will return to the user
/* We are going to have to include the size of our data struct when we are searching for open memory*/
no_of_chars = no_of_chars + sizeof(struct memBlock);
mem_location = 0; // set to 0 until a proper size has been found
cur_location = managed_memory_start; // start at the beginning of our allocated memory
// go until there is no more memory left, allocate until we get to the end of our managed memory
while (managed_memory_start != NULL) {
/*cur_location and cur_loc_mcb are at the same address initially,
but we use the current location as a pointer to move around our managed memory*/
cur_loc_mcb = (memBlock *)cur_location;
// if our current location is not used
if (!cur_loc_mcb->is_used) {
if (cur_loc_mcb->size >= no_of_chars) {
// we have found a size big enough or equal to what the user asks for
cur_loc_mcb->is_used = 1;
mem_location = cur_location;
break;
}
}
// at this point we dont have a size big enough, move to the next one
cur_location = cur_location + cur_loc_mcb->size;
}
/*Move the memory past or MCB and return*/
mem_location = mem_location + sizeof(struct memBlock);
return mem_location;
}
最佳答案
在代码中的某个位置设置 mem_location
mem_location = cur_location;
之后，在返回其值之前，您可以更改它
mem_location = mem_location + sizeof(struct memBlock);
好像不太对劲……
关于c - 使用数据结构来处理内存的个人 malloc 函数，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/5293315/