Files
RockOS/kernel/vfs.c

130 lines
2.8 KiB
C

#include <vfs.h>
#include <process.h>
#include <scheduler.h>
#include <lib/memory.h>
#include <lib/string.h>
#include <lib/print.h>
vfs_node_t* root = NULL;
vfs_node_t* vfs_create_root() {
root = kalloc(sizeof(vfs_node_t));
memset((uint8_t*)root, 0, sizeof(vfs_node_t));
strcpy(root->name, "root");
root->flags |= VFS_DIRECTORY;
root->size = 0;
root->find = NULL;
return root;
}
void vfs_mount(vfs_node_t* _mnt, vfs_node_t* _fs) {
if (!_fs || !_mnt || !(_mnt->flags & VFS_DIRECTORY)) return;
_mnt->mnt = _fs;
}
vfs_node_t* vfs_find(const char* path) {
vfs_node_t* current = root;
if (current->mnt) {
current = current->mnt;
}
char* sav = NULL;
size_t path_sz = strlen(path) + 1;
char* path_cpy = kalloc(path_sz);
memset((uint8_t*)path_cpy, 0, path_sz);
memcpy(path, path_cpy, path_sz);
char* tkn = strtok_r(path_cpy, "/", &sav);
while (tkn != NULL) {
if (current && current->mnt) {
current = current->mnt;
}
if (!current || !current->find) {
return NULL;
}
current = current->find(current, tkn);
if (current == NULL) {
return NULL;
}
tkn = strtok_r(NULL, "/", &sav);
if (tkn && !(current->flags & VFS_DIRECTORY)) {
return NULL;
}
}
kfree(path_cpy);
return current;
}
vfs_node_t* vfs_mkdir(vfs_node_t* parent, const char* name) {
if (!parent || !name) {
return NULL;
}
if (strlen(name) == 0) {
return NULL;
}
return parent->mkdir(parent, name);
}
int vfs_open(const char* _path, int flags) {
vfs_node_t* file = vfs_find(_path);
if (!file) return -1;
file_t* f = (file_t*)kalloc(sizeof(file_t));
f->node = file;
f->offset = 0;
f->flags = flags;
return alloc_fd(f);
}
int vfs_read(int fd, void* buf, size_t sz) {
process_t* curr_p = current_task();
if (fd < 0 || fd >= MAX_PROCESS_FDS || !curr_p->fd_table[fd]->node) {
return -1;
}
file_t* file = curr_p->fd_table[fd];
if (!file->node->read) return -1;
uint32_t bytes_read = file->node->read(file->node, file->offset, sz, buf);
file->offset += bytes_read;
return bytes_read;
}
int vfs_seek(int fd, size_t offset) {
process_t* curr_p = current_task();
if (fd < 0 || fd >= MAX_PROCESS_FDS || !curr_p->fd_table[fd]->node) {
return 0;
}
file_t* file = curr_p->fd_table[fd];
file->offset = offset;
return 1;
}
int alloc_fd(file_t* f) {
process_t* curr_p = current_task();
if (!curr_p) return -1;
for (int i = 0; i < MAX_PROCESS_FDS; i++) {
if (curr_p->fd_table[i] == NULL) {
curr_p->fd_table[i] = f;
return i;
}
}
return -1;
}