error_t FAT::traverse(Path path, dirvector& ents, const Dirent* const start) const
{
// start with given entry (defaults to root)
uint32_t cluster = start ? start->block() : 0;
Dirent found(this, INVALID_ENTITY);
while (!path.empty()) {
auto S = this->cl_to_sector(cluster);
ents.clear(); // mui importante
// sync read entire directory
auto err = int_ls(S, ents);
if (UNLIKELY(err)) return err;
// the name we are looking for
const std::string name = path.front();
path.pop_front();
// check for matches in dirents
for (auto& e : ents)
if (UNLIKELY(e.name() == name)) {
// go to this directory, unless its the last name
FS_PRINT("traverse_sync: Found match for %s", name.c_str());
// enter the matching directory
FS_PRINT("\t\t cluster: %lu\n", e.block());
// only follow if the name is a directory
if (e.type() == DIR) {
found = e;
break;
}
else {
// not dir = error, for now
return { error_t::E_NOTDIR, "Cannot list non-directory" };
}
} // for (ents)
// validate result
if (found.type() == INVALID_ENTITY) {
FS_PRINT("traverse_sync: NO MATCH for %s\n", name.c_str());
return { error_t::E_NOENT, name };
}
// set next cluster
cluster = found.block();
}
auto S = this->cl_to_sector(cluster);
// read result directory entries into ents
ents.clear(); // mui importante!
return int_ls(S, ents);
}
List FAT::ls(const Dirent& ent) const
{
auto ents = std::make_shared<dirvector> ();
// verify ent is a directory
if (!ent.is_valid() || !ent.is_dir())
return { { error_t::E_NOTDIR, ent.name() }, ents };
// convert cluster to sector
auto S = this->cl_to_sector(ent.block());
// read result directory entries into ents
auto err = int_ls(S, *ents);
return { err, ents };
}
void FAT::ls(const Dirent& ent, on_ls_func on_ls) const
{
auto dirents = std::make_shared<dirvector> ();
// verify ent is a directory
if (!ent.is_valid() || !ent.is_dir()) {
on_ls( { error_t::E_NOTDIR, ent.name() }, dirents );
return;
}
// convert cluster to sector
uint32_t S = this->cl_to_sector(ent.block());
// read result directory entries into ents
int_ls(S, dirents, on_ls);
}
void FAT::traverse(std::shared_ptr<Path> path, cluster_func callback)
{
// parse this path into a stack of memes
typedef std::function<void(uint32_t)> next_func_t;
// asynch stack traversal
auto next = std::make_shared<next_func_t> ();
auto weak_next = std::weak_ptr<next_func_t>(next);
*next =
[this, path, weak_next, callback] (uint32_t cluster) {
if (path->empty()) {
// attempt to read directory
uint32_t S = this->cl_to_sector(cluster);
// result allocated on heap
auto dirents = std::make_shared<std::vector<Dirent>> ();
int_ls(S, dirents,
[callback] (error_t error, dirvec_t ents) {
callback(error, ents);
});
return;
}
// retrieve next name
std::string name = path->front();
path->pop_front();
uint32_t S = this->cl_to_sector(cluster);
debug("Current target: %s on cluster %u (sector %u)\n", name.c_str(), cluster, S);
// result allocated on heap
auto dirents = std::make_shared<std::vector<Dirent>> ();
auto next = weak_next.lock();
// list directory contents
int_ls(S, dirents,
[name, dirents, next, callback] (error_t err, dirvec_t ents) {
if (unlikely(err)) {
debug("Could not find: %s\n", name.c_str());
callback(err, dirents);
return;
}
// look for name in directory
for (auto& e : *ents) {
if (unlikely(e.name() == name)) {
// go to this directory, unless its the last name
debug("Found match for %s", name.c_str());
// enter the matching directory
debug("\t\t cluster: %llu\n", e.block);
// only follow directories
if (e.type() == DIR)
(*next)(e.block);
else
callback({ error_t::E_NOTDIR, e.name() }, dirents);
return;
}
} // for (ents)
debug("NO MATCH for %s\n", name.c_str());
callback({ error_t::E_NOENT, name }, dirents);
});
};
// start by reading root directory
(*next)(0);
}
