disk.cpp

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

char disk[MAX_BLOCK][BLOCK_SIZE];
char data_disk[BLOCK_SIZE];
char buff[BLOCK_SIZE * BUFFER];
int buf_size = 0;

int disk_read(int block, char *buf)
{
	if(block < 0 || block >= MAX_BLOCK /*|| strlen(buf) < strlen(disk[block])*/) {
		printf("disk_read error\n");
		return -1;
	}
	memcpy(buf, disk[block], BLOCK_SIZE);

	return 0;
}

int disk_write(int block, char *buf)
{
	if(block < 0 || block >= MAX_BLOCK /*|| strlen(disk[block]) < strlen(buf)*/) {
		printf("disk_write error\n");
		return -1;
	}
	memcpy(disk[block], buf, BLOCK_SIZE);

	return 0;
}

int disk_mount(char *name)
{
	FILE *fp = fopen(name, "r");
	if(fp != NULL) {
		fread(disk, BLOCK_SIZE, MAX_BLOCK, fp);
		fclose(fp);
		return 1;
	}
	return 0;
}

int disk_umount(char *name)
{
	FILE *fp = fopen(name, "w");
	if(fp == NULL) {
		fprintf(stderr, "disk_umount: file open error! %s\n", name);
		return -1;
	}

	fwrite(disk, BLOCK_SIZE, MAX_BLOCK, fp);
	fclose(fp);
	return 1;
}

int data_disk_read(char *name, int block, char *buf)
{

	FILE *fp = fopen(name, "r");
	if (fp != NULL) {
		fseek(fp, (long long)block * BLOCK_SIZE, 0);
		fread(data_disk, BLOCK_SIZE, 1, fp);
		memcpy(buf, data_disk, BLOCK_SIZE);
		fclose(fp);
		return 1;
	}
	return 0;
}

int data_disk_write(char *name, int block, char *buf)
{
	memcpy(buff + buf_size * BLOCK_SIZE, buf, BLOCK_SIZE);
	buf_size++;
	if (buf_size == BUFFER) {
		FILE *fp = fopen(name, "a");
		buf_size = 0;
		if (fp != NULL) {
			fwrite(buff, BLOCK_SIZE, BUFFER, fp);
			fclose(fp);
			return 1;
		}
	}
	return 0;
}

int small_sst_read(char *name, int sst_size, char *buf)
{
        FILE *fp = fopen(name, "r");
        int buf_len = sst_size * 16;
        if (fp != NULL) {
                fread(buf, buf_len, 1, fp);
                fclose(fp);
                return 1;
        }
        return 0;
}

int small_sst_write(char *name, int sst_size, char *buf)
{
        FILE *fp = fopen(name, "w");
        int buf_len = sst_size * 16;
        if (fp != NULL) {
                fwrite(buf, buf_len, 1, fp);
                fclose(fp);
                return 1;
        }
        return 0;
}

int sst_read(char *name, int sst_size, char *buf)
{
	FILE *fp = fopen(name, "r");
	long long buf_len = sst_size * 16LL;
	if (fp != NULL) {
		fread(buf, BLOCK_SIZE, buf_len / BLOCK_SIZE, fp);
		fclose(fp);
		return 1;
	}
	return 0;
}

int sst_write(char *name, int sst_size, char *buf)
{
	FILE *fp = fopen(name, "w");
	long long buf_len = sst_size * 16LL;
	if (fp != NULL) {
		fwrite(buf, BLOCK_SIZE, buf_len / BLOCK_SIZE + (buf_len % BLOCK_SIZE == 0), fp);
		fclose(fp);
		return 1;
	}
	return 0;
}

int sst_read_index(char *name, int index, char *buf)
{
	FILE *fp = fopen(name, "r");
	if (fp != NULL) {
		fseek(fp, (long long)index * 16, 0);
		fread(buf, 16, 1, fp);
		fclose(fp);
		return 1;
	}
	return 0;
}

int sst_read_pos(int num, int pos, char *buf)
{
	char name[20];
	snprintf(name, sizeof(name), "sst_%d", num);
	FILE *fp = fopen(name, "r");
	if (fp != NULL) {
			fseek(fp, (long long)pos * BLOCK_SIZE, 0);
			fread(buf, BLOCK_SIZE, 1, fp);
			fclose(fp);
			return 1;
	}
	return 0;
}