void
VA_Resize_IMP(VArray *self, uint32_t size) {
if (size < self->size) {
VA_Excise(self, size, self->size - size);
}
else if (size > self->size) {
VA_Grow(self, size);
}
self->size = size;
}
static void
SI_grow_by(VArray *self, uint32_t add_size) {
size_t min_size = self->size + add_size;
// Check for overflow.
if ((uint32_t)min_size < add_size) {
THROW(ERR, "Array grew too large");
}
size_t new_size = Memory_oversize(min_size, sizeof(Obj*));
if (new_size > UINT32_MAX) { new_size = UINT32_MAX; }
VA_Grow(self, (uint32_t)new_size);
}
static void
S_add_to_file_list(Folder *self, VArray *list, CharBuf *dir, CharBuf *prefix) {
size_t orig_prefix_size = CB_Get_Size(prefix);
DirHandle *dh = Folder_Open_Dir(self, dir);
CharBuf *entry;
if (!dh) {
RETHROW(INCREF(Err_get_error()));
}
entry = DH_Get_Entry(dh);
while (DH_Next(dh)) { // Updates entry
if (!S_is_updir(entry)) {
CharBuf *relpath = CB_newf("%o%o", prefix, entry);
if (VA_Get_Size(list) == VA_Get_Capacity(list)) {
VA_Grow(list, VA_Get_Size(list) * 2);
}
VA_Push(list, (Obj*)relpath);
if (DH_Entry_Is_Dir(dh) && !DH_Entry_Is_Symlink(dh)) {
CharBuf *subdir = CB_Get_Size(dir)
? CB_newf("%o/%o", dir, entry)
: CB_Clone(entry);
CB_catf(prefix, "%o/", entry);
S_add_to_file_list(self, list, subdir, prefix); // recurse
CB_Set_Size(prefix, orig_prefix_size);
DECREF(subdir);
}
}
}
if (!DH_Close(dh)) {
RETHROW(INCREF(Err_get_error()));
}
DECREF(dh);
}
static void
S_discover_unused(FilePurger *self, VArray **purgables_ptr,
VArray **snapshots_ptr)
{
Folder *folder = self->folder;
DirHandle *dh = Folder_Open_Dir(folder, NULL);
if (!dh) { RETHROW(INCREF(Err_get_error())); }
VArray *spared = VA_new(1);
VArray *snapshots = VA_new(1);
CharBuf *snapfile = NULL;
// Start off with the list of files in the current snapshot.
if (self->snapshot) {
VArray *entries = Snapshot_List(self->snapshot);
VArray *referenced = S_find_all_referenced(folder, entries);
VA_Push_VArray(spared, referenced);
DECREF(entries);
DECREF(referenced);
snapfile = Snapshot_Get_Path(self->snapshot);
if (snapfile) { VA_Push(spared, INCREF(snapfile)); }
}
CharBuf *entry = DH_Get_Entry(dh);
Hash *candidates = Hash_new(64);
while (DH_Next(dh)) {
if (!CB_Starts_With_Str(entry, "snapshot_", 9)) { continue; }
else if (!CB_Ends_With_Str(entry, ".json", 5)) { continue; }
else if (snapfile && CB_Equals(entry, (Obj*)snapfile)) { continue; }
else {
Snapshot *snapshot
= Snapshot_Read_File(Snapshot_new(), folder, entry);
Lock *lock
= IxManager_Make_Snapshot_Read_Lock(self->manager, entry);
VArray *snap_list = Snapshot_List(snapshot);
VArray *referenced = S_find_all_referenced(folder, snap_list);
// DON'T obtain the lock -- only see whether another
// entity holds a lock on the snapshot file.
if (lock) {
Lock_Clear_Stale(lock);
}
if (lock && Lock_Is_Locked(lock)) {
// The snapshot file is locked, which means someone's using
// that version of the index -- protect all of its entries.
uint32_t new_size = VA_Get_Size(spared)
+ VA_Get_Size(referenced) + 1;
VA_Grow(spared, new_size);
VA_Push(spared, (Obj*)CB_Clone(entry));
VA_Push_VArray(spared, referenced);
}
else {
// No one's using this snapshot, so all of its entries are
// candidates for deletion.
for (uint32_t i = 0, max = VA_Get_Size(referenced); i < max; i++) {
CharBuf *file = (CharBuf*)VA_Fetch(referenced, i);
Hash_Store(candidates, (Obj*)file, INCREF(&EMPTY));
}
VA_Push(snapshots, INCREF(snapshot));
}
DECREF(referenced);
DECREF(snap_list);
DECREF(snapshot);
DECREF(lock);
}
}
DECREF(dh);
// Clean up after a dead segment consolidation.
S_zap_dead_merge(self, candidates);
// Eliminate any current files from the list of files to be purged.
for (uint32_t i = 0, max = VA_Get_Size(spared); i < max; i++) {
CharBuf *filename = (CharBuf*)VA_Fetch(spared, i);
DECREF(Hash_Delete(candidates, (Obj*)filename));
}
// Pass back purgables and Snapshots.
*purgables_ptr = Hash_Keys(candidates);
*snapshots_ptr = snapshots;
DECREF(candidates);
DECREF(spared);
}
