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#include "fat.h"
#include "ata.h"
#include "panic.h"
#include "fs.h"
void load_fat() {
read_sectors(FAT_INFO->reserved_sectors, FAT_INFO->sectors_per_fat, FAT);
}
bool to_fat_name(uint8_t *sname, uint8_t *fname) {
uint8_t *sp = sname, *fp = fname;
while (*sp != '.') {
if (!*sp) {
while (fp != fname + 11)
*(fp++) = ' ';
return false;
}
if (sp == sname + 8)
return true;
*(fp++) = *(sp++);
}
while (fp != fname + 8)
*(fp++) = ' ';
while (*++sp) {
if (fp == fname + 11)
return true;
*(fp++) = *sp;
}
while (fp != fname + 11)
*(fp++) = ' ';
return false;
}
bool check_fat_names(uint8_t *lname, uint8_t *rname) {
return (* (uint32_t *)lname == *(uint32_t *)rname) &&
(*((uint32_t *)lname + 1) == *((uint32_t *)rname + 1)) &&
(*((uint16_t *)lname + 4) == *((uint16_t *)rname + 4)) &&
(*( lname + 10) == *( rname + 10));
}
struct directory_entry buffer[16];
uint16_t dir_start, buffer_from;
void load_root() {
dir_start = FAT_INFO->reserved_sectors + FAT_INFO->sectors_per_fat;
}
struct directory_entry *load_subentry(uint8_t *name) {
uint8_t fname[11];
if (to_fat_name(name, fname))
return 0;
struct directory_entry *ptr = buffer;
uint16_t dir_current = dir_start;
read_sectors(buffer_from = dir_current, 1, buffer);
while (*(uint8_t *)ptr) {
if (check_fat_names(ptr->name, fname))
return ptr;
if (++ptr == buffer + 16) {
read_sectors(buffer_from = ++dir_current, 1, buffer);
ptr = buffer;
}
};
return 0;
}
bool load_subdir(uint8_t *name) {
struct directory_entry *e = load_subentry(name);
if (!e)
return true;
dir_start = CTOS(e->first_cluster);
return false;
}
struct directory_entry *load_entry(uint8_t *path) {
load_root();
for (uint8_t *ptr = path; *ptr; ++ptr)
if (*ptr == '/') {
*ptr = 0;
if (load_subdir(path))
return 0;
path = ptr + 1;
}
return load_subentry(path);
}
bool get_entry(uint8_t *path, struct directory_entry *at) {
struct directory_entry *e = load_entry(path);
if (!e)
return true;
*at = *e;
return false;
}
bool update_entry(uint8_t *path, struct directory_entry *value) {
struct directory_entry *e = load_entry(path);
if (!e)
return true;
*e = *value;
write_sectors(buffer_from, 1, buffer);
return false;
}
bool create_entry(uint8_t *dir_path, struct directory_entry *value) {
fs_handle h = fs_open(dir_path);
struct directory_entry *check;
while (fs_read(h, 32, check))
if (check_fat_names(check->name, value->name)) {
fs_close(h);
return true;
}
fs_write(h, 32, value);
fs_close(h);
return false;
}
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