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/**
* This is just a test program, it does nothing but just
* init the cache first then use get_cache_sector to test
* the LRU algorithm with 12 fake-sector number.
*
* And it work well here
*
*/
#include <stdio.h>
#include "cache.h"
#include "ext2_fs.h"
#include <fcntl.h>
#include <sys/stat.h>
struct ext2_super_block sb;
int fd;
extern struct cache_struct cache[CACHE_ENTRIES + 1];
/**
* Just print the sector, and according the LRU algorithm,
* Left most value is the most least secotr, and Right most
* value is the most Recent sector. I see it's a Left Right Used
* (LRU) algorithm; Just kidding:)
*/
void print_cache(void)
{
int i = 0;
struct cache_struct *cs = cache;
for (; i < CACHE_ENTRIES; i++) {
cs = cs->next;
printf("%d ", cs->block);
}
printf("\n");
}
/* test function */
void print_hex(char *data, int size)
{
int i = 0;
while ( size --) {
if ( (i != 0) && (i % 16 == 0) )
printf("\n");
i ++;
if ( (*data < 0x20 ) || (*data > 0x80 ) ) {
printf(".");
data ++;
continue;
}
putc(*data, stdout);
data++;
}
printf("\n");
}
void usage(void)
{
printf("USAGE: a.out ext2fs.img filename\n");
printf("---- ext2fs.img means a ext2 filesytem image\n");
printf("---- filename menas the file you wanna open, it can be \n");
printf(" in one of the two following forms:\n");
printf(" /file/name/xy.y, this is a full name, or \n");
printf(" file/name/xy.z, in this case, the program will search\n");
printf(" from the directory where the extlinux.sys stored\n");
}
/**
* well, it's just a test program that test if the fs driver
* would work on ext2/3(ext4 not added for now) filesystem
* well or not. so it's task is simple,too: open the ext2fs,
* then read what you want.
*
*/
int main(int argc, char *argv[])
{
int bytes_read = 0;
int total_bytes = 0;
int have_more;
char *ext2fs = argv[1];
char *filename = argv[2];
char buf[1024];
struct cache_struct *cs;
struct open_file_t *file = NULL;
if (argc != 3 ) {
usage();
return 0;
}
/* init. the cache */
cache_init();
fd = open(ext2fs, O_RDONLY);
if ( fd < 0 ) {
printf("File %s open error....\n", ext2fs);
return 0;
}
init_fs(&sb);
file = (struct open_file_t *)open_file(filename);
if ( ! file ) {
printf("open file error: file %s not found ....\n", filename);
close(fd);
return 0;
}
/*
* The following message may be nosiy, but it told we how is it
* going well.
*/
do {
bytes_read = read_file(file, buf, 1024, &have_more);
printf("--------read %d bytes-------\n", bytes_read);
printf("----------------\n");
print_hex(buf, bytes_read);
total_bytes += bytes_read;
}while(have_more);
printf("-------------total read %d bytes------\n", total_bytes);
close(fd);
return 0;
}
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