#include <error.h>
#include <string.h>
#include "dtl.h"

/* Memory_info 结构 伪构造函数 */
static struct Memory_info *
memory_info_init(size_t size, struct Memory_info *next, const char *a);

/* Memory_status 结构初始化函数 */
static void
memory_status_init(void);

static struct Memory_status memory_status_dbtools = {0, 0, NULL};

void
memory_status_init(void)
{
    memory_status_dbtools.all_size          = 0;
    memory_status_dbtools.count             = 0;
    memory_status_dbtools.front             = memory_info_init(0, NULL, "root");
}

void*
__malloc(size_t size, const char *a)
{
    /* 确保已经初始化 */
    if(memory_status_dbtools.front == NULL)
        memory_status_init();

    struct Memory_info *it = memory_status_dbtools.front;
    /* 寻找不大于当前内存块的第一个位置 */
    while((it->next != NULL) && (it->next->size > size))
        it = it->next;
    
    /* 分配内存块 */
    it->next = memory_info_init(size, it->next, a);

    /* 分配成功 修改总数据 */
    memory_status_dbtools.all_size += size;
    memory_status_dbtools.count++;

    return it->next->address;
}


void 
__free(void *ptr) 
{
    /* 避免释放不存在的内存 */
    if(NULL == ptr)
        return;

    /* 确保已经初始化 */
    if(memory_status_dbtools.front == NULL)
        memory_status_init();

    struct Memory_info      *it = memory_status_dbtools.front;
    while(it->next != NULL) {
        /* 找到对应的地址块信息就在信息链表中删除 */
        if(ptr == it->next->address) {
            struct Memory_info  *temp = it->next->next;
            memory_status_dbtools.all_size -= it->next->size;
            memory_status_dbtools.count--;

            free(ptr);
            ptr = NULL;
            free(it->next);
            it->next = temp;
            break;
        }
        it = it->next;
    }
}

extern void
__display_memory_status(void) 
{
    printf("\n---Memory status---\n");
    printf("All_size:   %ld\n", memory_status_dbtools.all_size);
    printf("count:      %d\n", memory_status_dbtools.count);

    printf("---  Stat Info  ---\n");
    struct Memory_info      *it = memory_status_dbtools.front->next;
    while(NULL != it) {
        printf("%p\n", it->address);
        printf("%ld\n", it->size);
        printf(it->message);
        printf("\n----------------\n");
        it = it->next;
    }
    printf("\n\n");
}


struct Memory_info *
memory_info_init(size_t size, struct Memory_info *next, const char *a)
{
    struct Memory_info  *dst;
    dst = (struct Memory_info*)malloc(sizeof(struct Memory_info));
    if(NULL == dst)
        perror("memory_info_init: malloc fail!");

    dst->size = size;
    dst->next = next;
    if(size != 0) {
        dst->address = malloc(size);
        if(NULL == dst->address)
            perror("memory_info_init: malloc fail!");
    } else dst->address = NULL;
    strncpy(dst->message, a, 31);
    return dst;
}