toaruos/kernel/core/vfs.c

103 lines
2.2 KiB
C

#include <system.h>
#include <fs.h>
fs_node_t *fs_root = 0;
uint32_t read_fs(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
if (node->read != 0) {
return node->read(node, offset, size, buffer);
} else {
return 0;
}
}
uint32_t write_fs(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
if (node->write != 0) {
return node->write(node, offset, size, buffer);
} else {
return 0;
}
}
void open_fs(fs_node_t *node, uint8_t read, uint8_t write) {
if (node->open != 0) {
node->open(node, read, write);
}
}
void close_fs(fs_node_t *node) {
if (node->close != 0) {
node->close(node);
}
}
struct dirent * readdir_fs(fs_node_t *node, uint32_t index) {
if ((node->flags & FS_DIRECTORY) && node->readdir != NULL) {
return node->readdir(node, index);
} else {
return (struct dirent *)NULL;
}
}
fs_node_t *finddir_fs(fs_node_t *node, char *name) {
if ((node->flags & FS_DIRECTORY) && node->readdir != NULL) {
return node->finddir(node, name);
} else {
return (fs_node_t *)NULL;
}
}
/*
* Retreive the node for the requested path
*/
fs_node_t *
kopen(
const char *filename,
uint32_t flags
) {
/* let's do this shit */
if (!fs_root) {
HALT_AND_CATCH_FIRE("Attempted to kopen() without a filesystem in place.");
}
if (!filename) {
HALT_AND_CATCH_FIRE("Attempted to kopen() without a filename.");
}
if (filename[0] != '/') {
HALT_AND_CATCH_FIRE("Attempted to kopen() a non-absolute path.");
}
size_t path_len = strlen(filename);
if (path_len == 1) {
return fs_root;
}
char * path = (char *)malloc(sizeof(char) * (path_len + 1));
memcpy(path, filename, path_len);
char * path_offset = path;
uint32_t path_depth = 0;
while (path_offset < path + path_len) {
if (*path_offset == '/') {
*path_offset = '\0';
path_depth++;
}
path_offset++;
}
path[path_len] = '\0';
path_offset = path + 1;
uint32_t depth;
fs_node_t * node_ptr = fs_root;
for (depth = 0; depth < path_depth; ++depth) {
node_ptr = finddir_fs(node_ptr, path_offset);
if (!node_ptr) {
free((void *)path);
return NULL;
} else if (depth == path_depth - 1) {
open_fs(node_ptr, 1, 0);
return node_ptr;
}
path_offset += strlen(path_offset) + 1;
}
free((void *)path);
return NULL;
}